| //===-- DAGCombiner.cpp - Implement a DAG node combiner -------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This pass combines dag nodes to form fewer, simpler DAG nodes. It can be run |
| // both before and after the DAG is legalized. |
| // |
| // This pass is not a substitute for the LLVM IR instcombine pass. This pass is |
| // primarily intended to handle simplification opportunities that are implicit |
| // in the LLVM IR and exposed by the various codegen lowering phases. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "dagcombine" |
| #include "llvm/CodeGen/SelectionDAG.h" |
| #include "llvm/ADT/SmallPtrSet.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/Analysis/AliasAnalysis.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/DerivedTypes.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/Support/CommandLine.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/MathExtras.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/Target/TargetLowering.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include "llvm/Target/TargetOptions.h" |
| #include <algorithm> |
| using namespace llvm; |
| |
| STATISTIC(NodesCombined , "Number of dag nodes combined"); |
| STATISTIC(PreIndexedNodes , "Number of pre-indexed nodes created"); |
| STATISTIC(PostIndexedNodes, "Number of post-indexed nodes created"); |
| STATISTIC(OpsNarrowed , "Number of load/op/store narrowed"); |
| STATISTIC(LdStFP2Int , "Number of fp load/store pairs transformed to int"); |
| |
| namespace { |
| static cl::opt<bool> |
| CombinerAA("combiner-alias-analysis", cl::Hidden, |
| cl::desc("Turn on alias analysis during testing")); |
| |
| static cl::opt<bool> |
| CombinerGlobalAA("combiner-global-alias-analysis", cl::Hidden, |
| cl::desc("Include global information in alias analysis")); |
| |
| //------------------------------ DAGCombiner ---------------------------------// |
| |
| class DAGCombiner { |
| SelectionDAG &DAG; |
| const TargetLowering &TLI; |
| CombineLevel Level; |
| CodeGenOpt::Level OptLevel; |
| bool LegalOperations; |
| bool LegalTypes; |
| |
| // Worklist of all of the nodes that need to be simplified. |
| // |
| // This has the semantics that when adding to the worklist, |
| // the item added must be next to be processed. It should |
| // also only appear once. The naive approach to this takes |
| // linear time. |
| // |
| // To reduce the insert/remove time to logarithmic, we use |
| // a set and a vector to maintain our worklist. |
| // |
| // The set contains the items on the worklist, but does not |
| // maintain the order they should be visited. |
| // |
| // The vector maintains the order nodes should be visited, but may |
| // contain duplicate or removed nodes. When choosing a node to |
| // visit, we pop off the order stack until we find an item that is |
| // also in the contents set. All operations are O(log N). |
| SmallPtrSet<SDNode*, 64> WorkListContents; |
| SmallVector<SDNode*, 64> WorkListOrder; |
| |
| // AA - Used for DAG load/store alias analysis. |
| AliasAnalysis &AA; |
| |
| /// AddUsersToWorkList - When an instruction is simplified, add all users of |
| /// the instruction to the work lists because they might get more simplified |
| /// now. |
| /// |
| void AddUsersToWorkList(SDNode *N) { |
| for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end(); |
| UI != UE; ++UI) |
| AddToWorkList(*UI); |
| } |
| |
| /// visit - call the node-specific routine that knows how to fold each |
| /// particular type of node. |
| SDValue visit(SDNode *N); |
| |
| public: |
| /// AddToWorkList - Add to the work list making sure its instance is at the |
| /// back (next to be processed.) |
| void AddToWorkList(SDNode *N) { |
| WorkListContents.insert(N); |
| WorkListOrder.push_back(N); |
| } |
| |
| /// removeFromWorkList - remove all instances of N from the worklist. |
| /// |
| void removeFromWorkList(SDNode *N) { |
| WorkListContents.erase(N); |
| } |
| |
| SDValue CombineTo(SDNode *N, const SDValue *To, unsigned NumTo, |
| bool AddTo = true); |
| |
| SDValue CombineTo(SDNode *N, SDValue Res, bool AddTo = true) { |
| return CombineTo(N, &Res, 1, AddTo); |
| } |
| |
| SDValue CombineTo(SDNode *N, SDValue Res0, SDValue Res1, |
| bool AddTo = true) { |
| SDValue To[] = { Res0, Res1 }; |
| return CombineTo(N, To, 2, AddTo); |
| } |
| |
| void CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO); |
| |
| private: |
| |
| /// SimplifyDemandedBits - Check the specified integer node value to see if |
| /// it can be simplified or if things it uses can be simplified by bit |
| /// propagation. If so, return true. |
| bool SimplifyDemandedBits(SDValue Op) { |
| unsigned BitWidth = Op.getValueType().getScalarType().getSizeInBits(); |
| APInt Demanded = APInt::getAllOnesValue(BitWidth); |
| return SimplifyDemandedBits(Op, Demanded); |
| } |
| |
| bool SimplifyDemandedBits(SDValue Op, const APInt &Demanded); |
| |
| bool CombineToPreIndexedLoadStore(SDNode *N); |
| bool CombineToPostIndexedLoadStore(SDNode *N); |
| |
| void ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad); |
| SDValue PromoteOperand(SDValue Op, EVT PVT, bool &Replace); |
| SDValue SExtPromoteOperand(SDValue Op, EVT PVT); |
| SDValue ZExtPromoteOperand(SDValue Op, EVT PVT); |
| SDValue PromoteIntBinOp(SDValue Op); |
| SDValue PromoteIntShiftOp(SDValue Op); |
| SDValue PromoteExtend(SDValue Op); |
| bool PromoteLoad(SDValue Op); |
| |
| void ExtendSetCCUses(SmallVector<SDNode*, 4> SetCCs, |
| SDValue Trunc, SDValue ExtLoad, DebugLoc DL, |
| ISD::NodeType ExtType); |
| |
| /// combine - call the node-specific routine that knows how to fold each |
| /// particular type of node. If that doesn't do anything, try the |
| /// target-specific DAG combines. |
| SDValue combine(SDNode *N); |
| |
| // Visitation implementation - Implement dag node combining for different |
| // node types. The semantics are as follows: |
| // Return Value: |
| // SDValue.getNode() == 0 - No change was made |
| // SDValue.getNode() == N - N was replaced, is dead and has been handled. |
| // otherwise - N should be replaced by the returned Operand. |
| // |
| SDValue visitTokenFactor(SDNode *N); |
| SDValue visitMERGE_VALUES(SDNode *N); |
| SDValue visitADD(SDNode *N); |
| SDValue visitSUB(SDNode *N); |
| SDValue visitADDC(SDNode *N); |
| SDValue visitSUBC(SDNode *N); |
| SDValue visitADDE(SDNode *N); |
| SDValue visitSUBE(SDNode *N); |
| SDValue visitMUL(SDNode *N); |
| SDValue visitSDIV(SDNode *N); |
| SDValue visitUDIV(SDNode *N); |
| SDValue visitSREM(SDNode *N); |
| SDValue visitUREM(SDNode *N); |
| SDValue visitMULHU(SDNode *N); |
| SDValue visitMULHS(SDNode *N); |
| SDValue visitSMUL_LOHI(SDNode *N); |
| SDValue visitUMUL_LOHI(SDNode *N); |
| SDValue visitSMULO(SDNode *N); |
| SDValue visitUMULO(SDNode *N); |
| SDValue visitSDIVREM(SDNode *N); |
| SDValue visitUDIVREM(SDNode *N); |
| SDValue visitAND(SDNode *N); |
| SDValue visitOR(SDNode *N); |
| SDValue visitXOR(SDNode *N); |
| SDValue SimplifyVBinOp(SDNode *N); |
| SDValue SimplifyVUnaryOp(SDNode *N); |
| SDValue visitSHL(SDNode *N); |
| SDValue visitSRA(SDNode *N); |
| SDValue visitSRL(SDNode *N); |
| SDValue visitCTLZ(SDNode *N); |
| SDValue visitCTLZ_ZERO_UNDEF(SDNode *N); |
| SDValue visitCTTZ(SDNode *N); |
| SDValue visitCTTZ_ZERO_UNDEF(SDNode *N); |
| SDValue visitCTPOP(SDNode *N); |
| SDValue visitSELECT(SDNode *N); |
| SDValue visitSELECT_CC(SDNode *N); |
| SDValue visitSETCC(SDNode *N); |
| SDValue visitSIGN_EXTEND(SDNode *N); |
| SDValue visitZERO_EXTEND(SDNode *N); |
| SDValue visitANY_EXTEND(SDNode *N); |
| SDValue visitSIGN_EXTEND_INREG(SDNode *N); |
| SDValue visitTRUNCATE(SDNode *N); |
| SDValue visitBITCAST(SDNode *N); |
| SDValue visitBUILD_PAIR(SDNode *N); |
| SDValue visitFADD(SDNode *N); |
| SDValue visitFSUB(SDNode *N); |
| SDValue visitFMUL(SDNode *N); |
| SDValue visitFMA(SDNode *N); |
| SDValue visitFDIV(SDNode *N); |
| SDValue visitFREM(SDNode *N); |
| SDValue visitFCOPYSIGN(SDNode *N); |
| SDValue visitSINT_TO_FP(SDNode *N); |
| SDValue visitUINT_TO_FP(SDNode *N); |
| SDValue visitFP_TO_SINT(SDNode *N); |
| SDValue visitFP_TO_UINT(SDNode *N); |
| SDValue visitFP_ROUND(SDNode *N); |
| SDValue visitFP_ROUND_INREG(SDNode *N); |
| SDValue visitFP_EXTEND(SDNode *N); |
| SDValue visitFNEG(SDNode *N); |
| SDValue visitFABS(SDNode *N); |
| SDValue visitFCEIL(SDNode *N); |
| SDValue visitFTRUNC(SDNode *N); |
| SDValue visitFFLOOR(SDNode *N); |
| SDValue visitBRCOND(SDNode *N); |
| SDValue visitBR_CC(SDNode *N); |
| SDValue visitLOAD(SDNode *N); |
| SDValue visitSTORE(SDNode *N); |
| SDValue visitINSERT_VECTOR_ELT(SDNode *N); |
| SDValue visitEXTRACT_VECTOR_ELT(SDNode *N); |
| SDValue visitBUILD_VECTOR(SDNode *N); |
| SDValue visitCONCAT_VECTORS(SDNode *N); |
| SDValue visitEXTRACT_SUBVECTOR(SDNode *N); |
| SDValue visitVECTOR_SHUFFLE(SDNode *N); |
| SDValue visitMEMBARRIER(SDNode *N); |
| |
| SDValue XformToShuffleWithZero(SDNode *N); |
| SDValue ReassociateOps(unsigned Opc, DebugLoc DL, SDValue LHS, SDValue RHS); |
| |
| SDValue visitShiftByConstant(SDNode *N, unsigned Amt); |
| |
| bool SimplifySelectOps(SDNode *SELECT, SDValue LHS, SDValue RHS); |
| SDValue SimplifyBinOpWithSameOpcodeHands(SDNode *N); |
| SDValue SimplifySelect(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2); |
| SDValue SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2, |
| SDValue N3, ISD::CondCode CC, |
| bool NotExtCompare = false); |
| SDValue SimplifySetCC(EVT VT, SDValue N0, SDValue N1, ISD::CondCode Cond, |
| DebugLoc DL, bool foldBooleans = true); |
| SDValue SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp, |
| unsigned HiOp); |
| SDValue CombineConsecutiveLoads(SDNode *N, EVT VT); |
| SDValue ConstantFoldBITCASTofBUILD_VECTOR(SDNode *, EVT); |
| SDValue BuildSDIV(SDNode *N); |
| SDValue BuildUDIV(SDNode *N); |
| SDValue MatchBSwapHWordLow(SDNode *N, SDValue N0, SDValue N1, |
| bool DemandHighBits = true); |
| SDValue MatchBSwapHWord(SDNode *N, SDValue N0, SDValue N1); |
| SDNode *MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL); |
| SDValue ReduceLoadWidth(SDNode *N); |
| SDValue ReduceLoadOpStoreWidth(SDNode *N); |
| SDValue TransformFPLoadStorePair(SDNode *N); |
| SDValue reduceBuildVecExtToExtBuildVec(SDNode *N); |
| SDValue reduceBuildVecConvertToConvertBuildVec(SDNode *N); |
| |
| SDValue GetDemandedBits(SDValue V, const APInt &Mask); |
| |
| /// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes, |
| /// looking for aliasing nodes and adding them to the Aliases vector. |
| void GatherAllAliases(SDNode *N, SDValue OriginalChain, |
| SmallVector<SDValue, 8> &Aliases); |
| |
| /// isAlias - Return true if there is any possibility that the two addresses |
| /// overlap. |
| bool isAlias(SDValue Ptr1, int64_t Size1, |
| const Value *SrcValue1, int SrcValueOffset1, |
| unsigned SrcValueAlign1, |
| const MDNode *TBAAInfo1, |
| SDValue Ptr2, int64_t Size2, |
| const Value *SrcValue2, int SrcValueOffset2, |
| unsigned SrcValueAlign2, |
| const MDNode *TBAAInfo2) const; |
| |
| /// isAlias - Return true if there is any possibility that the two addresses |
| /// overlap. |
| bool isAlias(LSBaseSDNode *Op0, LSBaseSDNode *Op1); |
| |
| /// FindAliasInfo - Extracts the relevant alias information from the memory |
| /// node. Returns true if the operand was a load. |
| bool FindAliasInfo(SDNode *N, |
| SDValue &Ptr, int64_t &Size, |
| const Value *&SrcValue, int &SrcValueOffset, |
| unsigned &SrcValueAlignment, |
| const MDNode *&TBAAInfo) const; |
| |
| /// FindBetterChain - Walk up chain skipping non-aliasing memory nodes, |
| /// looking for a better chain (aliasing node.) |
| SDValue FindBetterChain(SDNode *N, SDValue Chain); |
| |
| /// Merge consecutive store operations into a wide store. |
| /// This optimization uses wide integers or vectors when possible. |
| /// \return True if some memory operations were changed. |
| bool MergeConsecutiveStores(StoreSDNode *N); |
| |
| public: |
| DAGCombiner(SelectionDAG &D, AliasAnalysis &A, CodeGenOpt::Level OL) |
| : DAG(D), TLI(D.getTargetLoweringInfo()), Level(BeforeLegalizeTypes), |
| OptLevel(OL), LegalOperations(false), LegalTypes(false), AA(A) {} |
| |
| /// Run - runs the dag combiner on all nodes in the work list |
| void Run(CombineLevel AtLevel); |
| |
| SelectionDAG &getDAG() const { return DAG; } |
| |
| /// getShiftAmountTy - Returns a type large enough to hold any valid |
| /// shift amount - before type legalization these can be huge. |
| EVT getShiftAmountTy(EVT LHSTy) { |
| return LegalTypes ? TLI.getShiftAmountTy(LHSTy) : TLI.getPointerTy(); |
| } |
| |
| /// isTypeLegal - This method returns true if we are running before type |
| /// legalization or if the specified VT is legal. |
| bool isTypeLegal(const EVT &VT) { |
| if (!LegalTypes) return true; |
| return TLI.isTypeLegal(VT); |
| } |
| }; |
| } |
| |
| |
| namespace { |
| /// WorkListRemover - This class is a DAGUpdateListener that removes any deleted |
| /// nodes from the worklist. |
| class WorkListRemover : public SelectionDAG::DAGUpdateListener { |
| DAGCombiner &DC; |
| public: |
| explicit WorkListRemover(DAGCombiner &dc) |
| : SelectionDAG::DAGUpdateListener(dc.getDAG()), DC(dc) {} |
| |
| virtual void NodeDeleted(SDNode *N, SDNode *E) { |
| DC.removeFromWorkList(N); |
| } |
| }; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // TargetLowering::DAGCombinerInfo implementation |
| //===----------------------------------------------------------------------===// |
| |
| void TargetLowering::DAGCombinerInfo::AddToWorklist(SDNode *N) { |
| ((DAGCombiner*)DC)->AddToWorkList(N); |
| } |
| |
| void TargetLowering::DAGCombinerInfo::RemoveFromWorklist(SDNode *N) { |
| ((DAGCombiner*)DC)->removeFromWorkList(N); |
| } |
| |
| SDValue TargetLowering::DAGCombinerInfo:: |
| CombineTo(SDNode *N, const std::vector<SDValue> &To, bool AddTo) { |
| return ((DAGCombiner*)DC)->CombineTo(N, &To[0], To.size(), AddTo); |
| } |
| |
| SDValue TargetLowering::DAGCombinerInfo:: |
| CombineTo(SDNode *N, SDValue Res, bool AddTo) { |
| return ((DAGCombiner*)DC)->CombineTo(N, Res, AddTo); |
| } |
| |
| |
| SDValue TargetLowering::DAGCombinerInfo:: |
| CombineTo(SDNode *N, SDValue Res0, SDValue Res1, bool AddTo) { |
| return ((DAGCombiner*)DC)->CombineTo(N, Res0, Res1, AddTo); |
| } |
| |
| void TargetLowering::DAGCombinerInfo:: |
| CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) { |
| return ((DAGCombiner*)DC)->CommitTargetLoweringOpt(TLO); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Helper Functions |
| //===----------------------------------------------------------------------===// |
| |
| /// isNegatibleForFree - Return 1 if we can compute the negated form of the |
| /// specified expression for the same cost as the expression itself, or 2 if we |
| /// can compute the negated form more cheaply than the expression itself. |
| static char isNegatibleForFree(SDValue Op, bool LegalOperations, |
| const TargetLowering &TLI, |
| const TargetOptions *Options, |
| unsigned Depth = 0) { |
| // fneg is removable even if it has multiple uses. |
| if (Op.getOpcode() == ISD::FNEG) return 2; |
| |
| // Don't allow anything with multiple uses. |
| if (!Op.hasOneUse()) return 0; |
| |
| // Don't recurse exponentially. |
| if (Depth > 6) return 0; |
| |
| switch (Op.getOpcode()) { |
| default: return false; |
| case ISD::ConstantFP: |
| // Don't invert constant FP values after legalize. The negated constant |
| // isn't necessarily legal. |
| return LegalOperations ? 0 : 1; |
| case ISD::FADD: |
| // FIXME: determine better conditions for this xform. |
| if (!Options->UnsafeFPMath) return 0; |
| |
| // After operation legalization, it might not be legal to create new FSUBs. |
| if (LegalOperations && |
| !TLI.isOperationLegalOrCustom(ISD::FSUB, Op.getValueType())) |
| return 0; |
| |
| // fold (fneg (fadd A, B)) -> (fsub (fneg A), B) |
| if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI, |
| Options, Depth + 1)) |
| return V; |
| // fold (fneg (fadd A, B)) -> (fsub (fneg B), A) |
| return isNegatibleForFree(Op.getOperand(1), LegalOperations, TLI, Options, |
| Depth + 1); |
| case ISD::FSUB: |
| // We can't turn -(A-B) into B-A when we honor signed zeros. |
| if (!Options->UnsafeFPMath) return 0; |
| |
| // fold (fneg (fsub A, B)) -> (fsub B, A) |
| return 1; |
| |
| case ISD::FMUL: |
| case ISD::FDIV: |
| if (Options->HonorSignDependentRoundingFPMath()) return 0; |
| |
| // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) or (fmul X, (fneg Y)) |
| if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI, |
| Options, Depth + 1)) |
| return V; |
| |
| return isNegatibleForFree(Op.getOperand(1), LegalOperations, TLI, Options, |
| Depth + 1); |
| |
| case ISD::FP_EXTEND: |
| case ISD::FP_ROUND: |
| case ISD::FSIN: |
| return isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI, Options, |
| Depth + 1); |
| } |
| } |
| |
| /// GetNegatedExpression - If isNegatibleForFree returns true, this function |
| /// returns the newly negated expression. |
| static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, |
| bool LegalOperations, unsigned Depth = 0) { |
| // fneg is removable even if it has multiple uses. |
| if (Op.getOpcode() == ISD::FNEG) return Op.getOperand(0); |
| |
| // Don't allow anything with multiple uses. |
| assert(Op.hasOneUse() && "Unknown reuse!"); |
| |
| assert(Depth <= 6 && "GetNegatedExpression doesn't match isNegatibleForFree"); |
| switch (Op.getOpcode()) { |
| default: llvm_unreachable("Unknown code"); |
| case ISD::ConstantFP: { |
| APFloat V = cast<ConstantFPSDNode>(Op)->getValueAPF(); |
| V.changeSign(); |
| return DAG.getConstantFP(V, Op.getValueType()); |
| } |
| case ISD::FADD: |
| // FIXME: determine better conditions for this xform. |
| assert(DAG.getTarget().Options.UnsafeFPMath); |
| |
| // fold (fneg (fadd A, B)) -> (fsub (fneg A), B) |
| if (isNegatibleForFree(Op.getOperand(0), LegalOperations, |
| DAG.getTargetLoweringInfo(), |
| &DAG.getTarget().Options, Depth+1)) |
| return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(), |
| GetNegatedExpression(Op.getOperand(0), DAG, |
| LegalOperations, Depth+1), |
| Op.getOperand(1)); |
| // fold (fneg (fadd A, B)) -> (fsub (fneg B), A) |
| return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(), |
| GetNegatedExpression(Op.getOperand(1), DAG, |
| LegalOperations, Depth+1), |
| Op.getOperand(0)); |
| case ISD::FSUB: |
| // We can't turn -(A-B) into B-A when we honor signed zeros. |
| assert(DAG.getTarget().Options.UnsafeFPMath); |
| |
| // fold (fneg (fsub 0, B)) -> B |
| if (ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(Op.getOperand(0))) |
| if (N0CFP->getValueAPF().isZero()) |
| return Op.getOperand(1); |
| |
| // fold (fneg (fsub A, B)) -> (fsub B, A) |
| return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(), |
| Op.getOperand(1), Op.getOperand(0)); |
| |
| case ISD::FMUL: |
| case ISD::FDIV: |
| assert(!DAG.getTarget().Options.HonorSignDependentRoundingFPMath()); |
| |
| // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) |
| if (isNegatibleForFree(Op.getOperand(0), LegalOperations, |
| DAG.getTargetLoweringInfo(), |
| &DAG.getTarget().Options, Depth+1)) |
| return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(), |
| GetNegatedExpression(Op.getOperand(0), DAG, |
| LegalOperations, Depth+1), |
| Op.getOperand(1)); |
| |
| // fold (fneg (fmul X, Y)) -> (fmul X, (fneg Y)) |
| return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(), |
| Op.getOperand(0), |
| GetNegatedExpression(Op.getOperand(1), DAG, |
| LegalOperations, Depth+1)); |
| |
| case ISD::FP_EXTEND: |
| case ISD::FSIN: |
| return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(), |
| GetNegatedExpression(Op.getOperand(0), DAG, |
| LegalOperations, Depth+1)); |
| case ISD::FP_ROUND: |
| return DAG.getNode(ISD::FP_ROUND, Op.getDebugLoc(), Op.getValueType(), |
| GetNegatedExpression(Op.getOperand(0), DAG, |
| LegalOperations, Depth+1), |
| Op.getOperand(1)); |
| } |
| } |
| |
| |
| // isSetCCEquivalent - Return true if this node is a setcc, or is a select_cc |
| // that selects between the values 1 and 0, making it equivalent to a setcc. |
| // Also, set the incoming LHS, RHS, and CC references to the appropriate |
| // nodes based on the type of node we are checking. This simplifies life a |
| // bit for the callers. |
| static bool isSetCCEquivalent(SDValue N, SDValue &LHS, SDValue &RHS, |
| SDValue &CC) { |
| if (N.getOpcode() == ISD::SETCC) { |
| LHS = N.getOperand(0); |
| RHS = N.getOperand(1); |
| CC = N.getOperand(2); |
| return true; |
| } |
| if (N.getOpcode() == ISD::SELECT_CC && |
| N.getOperand(2).getOpcode() == ISD::Constant && |
| N.getOperand(3).getOpcode() == ISD::Constant && |
| cast<ConstantSDNode>(N.getOperand(2))->getAPIntValue() == 1 && |
| cast<ConstantSDNode>(N.getOperand(3))->isNullValue()) { |
| LHS = N.getOperand(0); |
| RHS = N.getOperand(1); |
| CC = N.getOperand(4); |
| return true; |
| } |
| return false; |
| } |
| |
| // isOneUseSetCC - Return true if this is a SetCC-equivalent operation with only |
| // one use. If this is true, it allows the users to invert the operation for |
| // free when it is profitable to do so. |
| static bool isOneUseSetCC(SDValue N) { |
| SDValue N0, N1, N2; |
| if (isSetCCEquivalent(N, N0, N1, N2) && N.getNode()->hasOneUse()) |
| return true; |
| return false; |
| } |
| |
| SDValue DAGCombiner::ReassociateOps(unsigned Opc, DebugLoc DL, |
| SDValue N0, SDValue N1) { |
| EVT VT = N0.getValueType(); |
| if (N0.getOpcode() == Opc && isa<ConstantSDNode>(N0.getOperand(1))) { |
| if (isa<ConstantSDNode>(N1)) { |
| // reassoc. (op (op x, c1), c2) -> (op x, (op c1, c2)) |
| SDValue OpNode = |
| DAG.FoldConstantArithmetic(Opc, VT, |
| cast<ConstantSDNode>(N0.getOperand(1)), |
| cast<ConstantSDNode>(N1)); |
| return DAG.getNode(Opc, DL, VT, N0.getOperand(0), OpNode); |
| } |
| if (N0.hasOneUse()) { |
| // reassoc. (op (op x, c1), y) -> (op (op x, y), c1) iff x+c1 has one use |
| SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT, |
| N0.getOperand(0), N1); |
| AddToWorkList(OpNode.getNode()); |
| return DAG.getNode(Opc, DL, VT, OpNode, N0.getOperand(1)); |
| } |
| } |
| |
| if (N1.getOpcode() == Opc && isa<ConstantSDNode>(N1.getOperand(1))) { |
| if (isa<ConstantSDNode>(N0)) { |
| // reassoc. (op c2, (op x, c1)) -> (op x, (op c1, c2)) |
| SDValue OpNode = |
| DAG.FoldConstantArithmetic(Opc, VT, |
| cast<ConstantSDNode>(N1.getOperand(1)), |
| cast<ConstantSDNode>(N0)); |
| return DAG.getNode(Opc, DL, VT, N1.getOperand(0), OpNode); |
| } |
| if (N1.hasOneUse()) { |
| // reassoc. (op y, (op x, c1)) -> (op (op x, y), c1) iff x+c1 has one use |
| SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT, |
| N1.getOperand(0), N0); |
| AddToWorkList(OpNode.getNode()); |
| return DAG.getNode(Opc, DL, VT, OpNode, N1.getOperand(1)); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::CombineTo(SDNode *N, const SDValue *To, unsigned NumTo, |
| bool AddTo) { |
| assert(N->getNumValues() == NumTo && "Broken CombineTo call!"); |
| ++NodesCombined; |
| DEBUG(dbgs() << "\nReplacing.1 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith: "; |
| To[0].getNode()->dump(&DAG); |
| dbgs() << " and " << NumTo-1 << " other values\n"; |
| for (unsigned i = 0, e = NumTo; i != e; ++i) |
| assert((!To[i].getNode() || |
| N->getValueType(i) == To[i].getValueType()) && |
| "Cannot combine value to value of different type!")); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesWith(N, To); |
| if (AddTo) { |
| // Push the new nodes and any users onto the worklist |
| for (unsigned i = 0, e = NumTo; i != e; ++i) { |
| if (To[i].getNode()) { |
| AddToWorkList(To[i].getNode()); |
| AddUsersToWorkList(To[i].getNode()); |
| } |
| } |
| } |
| |
| // Finally, if the node is now dead, remove it from the graph. The node |
| // may not be dead if the replacement process recursively simplified to |
| // something else needing this node. |
| if (N->use_empty()) { |
| // Nodes can be reintroduced into the worklist. Make sure we do not |
| // process a node that has been replaced. |
| removeFromWorkList(N); |
| |
| // Finally, since the node is now dead, remove it from the graph. |
| DAG.DeleteNode(N); |
| } |
| return SDValue(N, 0); |
| } |
| |
| void DAGCombiner:: |
| CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) { |
| // Replace all uses. If any nodes become isomorphic to other nodes and |
| // are deleted, make sure to remove them from our worklist. |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(TLO.Old, TLO.New); |
| |
| // Push the new node and any (possibly new) users onto the worklist. |
| AddToWorkList(TLO.New.getNode()); |
| AddUsersToWorkList(TLO.New.getNode()); |
| |
| // Finally, if the node is now dead, remove it from the graph. The node |
| // may not be dead if the replacement process recursively simplified to |
| // something else needing this node. |
| if (TLO.Old.getNode()->use_empty()) { |
| removeFromWorkList(TLO.Old.getNode()); |
| |
| // If the operands of this node are only used by the node, they will now |
| // be dead. Make sure to visit them first to delete dead nodes early. |
| for (unsigned i = 0, e = TLO.Old.getNode()->getNumOperands(); i != e; ++i) |
| if (TLO.Old.getNode()->getOperand(i).getNode()->hasOneUse()) |
| AddToWorkList(TLO.Old.getNode()->getOperand(i).getNode()); |
| |
| DAG.DeleteNode(TLO.Old.getNode()); |
| } |
| } |
| |
| /// SimplifyDemandedBits - Check the specified integer node value to see if |
| /// it can be simplified or if things it uses can be simplified by bit |
| /// propagation. If so, return true. |
| bool DAGCombiner::SimplifyDemandedBits(SDValue Op, const APInt &Demanded) { |
| TargetLowering::TargetLoweringOpt TLO(DAG, LegalTypes, LegalOperations); |
| APInt KnownZero, KnownOne; |
| if (!TLI.SimplifyDemandedBits(Op, Demanded, KnownZero, KnownOne, TLO)) |
| return false; |
| |
| // Revisit the node. |
| AddToWorkList(Op.getNode()); |
| |
| // Replace the old value with the new one. |
| ++NodesCombined; |
| DEBUG(dbgs() << "\nReplacing.2 "; |
| TLO.Old.getNode()->dump(&DAG); |
| dbgs() << "\nWith: "; |
| TLO.New.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| |
| CommitTargetLoweringOpt(TLO); |
| return true; |
| } |
| |
| void DAGCombiner::ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad) { |
| DebugLoc dl = Load->getDebugLoc(); |
| EVT VT = Load->getValueType(0); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, VT, SDValue(ExtLoad, 0)); |
| |
| DEBUG(dbgs() << "\nReplacing.9 "; |
| Load->dump(&DAG); |
| dbgs() << "\nWith: "; |
| Trunc.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 0), Trunc); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 1), SDValue(ExtLoad, 1)); |
| removeFromWorkList(Load); |
| DAG.DeleteNode(Load); |
| AddToWorkList(Trunc.getNode()); |
| } |
| |
| SDValue DAGCombiner::PromoteOperand(SDValue Op, EVT PVT, bool &Replace) { |
| Replace = false; |
| DebugLoc dl = Op.getDebugLoc(); |
| if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Op)) { |
| EVT MemVT = LD->getMemoryVT(); |
| ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD) |
| ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD |
| : ISD::EXTLOAD) |
| : LD->getExtensionType(); |
| Replace = true; |
| return DAG.getExtLoad(ExtType, dl, PVT, |
| LD->getChain(), LD->getBasePtr(), |
| LD->getPointerInfo(), |
| MemVT, LD->isVolatile(), |
| LD->isNonTemporal(), LD->getAlignment()); |
| } |
| |
| unsigned Opc = Op.getOpcode(); |
| switch (Opc) { |
| default: break; |
| case ISD::AssertSext: |
| return DAG.getNode(ISD::AssertSext, dl, PVT, |
| SExtPromoteOperand(Op.getOperand(0), PVT), |
| Op.getOperand(1)); |
| case ISD::AssertZext: |
| return DAG.getNode(ISD::AssertZext, dl, PVT, |
| ZExtPromoteOperand(Op.getOperand(0), PVT), |
| Op.getOperand(1)); |
| case ISD::Constant: { |
| unsigned ExtOpc = |
| Op.getValueType().isByteSized() ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND; |
| return DAG.getNode(ExtOpc, dl, PVT, Op); |
| } |
| } |
| |
| if (!TLI.isOperationLegal(ISD::ANY_EXTEND, PVT)) |
| return SDValue(); |
| return DAG.getNode(ISD::ANY_EXTEND, dl, PVT, Op); |
| } |
| |
| SDValue DAGCombiner::SExtPromoteOperand(SDValue Op, EVT PVT) { |
| if (!TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, PVT)) |
| return SDValue(); |
| EVT OldVT = Op.getValueType(); |
| DebugLoc dl = Op.getDebugLoc(); |
| bool Replace = false; |
| SDValue NewOp = PromoteOperand(Op, PVT, Replace); |
| if (NewOp.getNode() == 0) |
| return SDValue(); |
| AddToWorkList(NewOp.getNode()); |
| |
| if (Replace) |
| ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode()); |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, NewOp.getValueType(), NewOp, |
| DAG.getValueType(OldVT)); |
| } |
| |
| SDValue DAGCombiner::ZExtPromoteOperand(SDValue Op, EVT PVT) { |
| EVT OldVT = Op.getValueType(); |
| DebugLoc dl = Op.getDebugLoc(); |
| bool Replace = false; |
| SDValue NewOp = PromoteOperand(Op, PVT, Replace); |
| if (NewOp.getNode() == 0) |
| return SDValue(); |
| AddToWorkList(NewOp.getNode()); |
| |
| if (Replace) |
| ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode()); |
| return DAG.getZeroExtendInReg(NewOp, dl, OldVT); |
| } |
| |
| /// PromoteIntBinOp - Promote the specified integer binary operation if the |
| /// target indicates it is beneficial. e.g. On x86, it's usually better to |
| /// promote i16 operations to i32 since i16 instructions are longer. |
| SDValue DAGCombiner::PromoteIntBinOp(SDValue Op) { |
| if (!LegalOperations) |
| return SDValue(); |
| |
| EVT VT = Op.getValueType(); |
| if (VT.isVector() || !VT.isInteger()) |
| return SDValue(); |
| |
| // If operation type is 'undesirable', e.g. i16 on x86, consider |
| // promoting it. |
| unsigned Opc = Op.getOpcode(); |
| if (TLI.isTypeDesirableForOp(Opc, VT)) |
| return SDValue(); |
| |
| EVT PVT = VT; |
| // Consult target whether it is a good idea to promote this operation and |
| // what's the right type to promote it to. |
| if (TLI.IsDesirableToPromoteOp(Op, PVT)) { |
| assert(PVT != VT && "Don't know what type to promote to!"); |
| |
| bool Replace0 = false; |
| SDValue N0 = Op.getOperand(0); |
| SDValue NN0 = PromoteOperand(N0, PVT, Replace0); |
| if (NN0.getNode() == 0) |
| return SDValue(); |
| |
| bool Replace1 = false; |
| SDValue N1 = Op.getOperand(1); |
| SDValue NN1; |
| if (N0 == N1) |
| NN1 = NN0; |
| else { |
| NN1 = PromoteOperand(N1, PVT, Replace1); |
| if (NN1.getNode() == 0) |
| return SDValue(); |
| } |
| |
| AddToWorkList(NN0.getNode()); |
| if (NN1.getNode()) |
| AddToWorkList(NN1.getNode()); |
| |
| if (Replace0) |
| ReplaceLoadWithPromotedLoad(N0.getNode(), NN0.getNode()); |
| if (Replace1) |
| ReplaceLoadWithPromotedLoad(N1.getNode(), NN1.getNode()); |
| |
| DEBUG(dbgs() << "\nPromoting "; |
| Op.getNode()->dump(&DAG)); |
| DebugLoc dl = Op.getDebugLoc(); |
| return DAG.getNode(ISD::TRUNCATE, dl, VT, |
| DAG.getNode(Opc, dl, PVT, NN0, NN1)); |
| } |
| return SDValue(); |
| } |
| |
| /// PromoteIntShiftOp - Promote the specified integer shift operation if the |
| /// target indicates it is beneficial. e.g. On x86, it's usually better to |
| /// promote i16 operations to i32 since i16 instructions are longer. |
| SDValue DAGCombiner::PromoteIntShiftOp(SDValue Op) { |
| if (!LegalOperations) |
| return SDValue(); |
| |
| EVT VT = Op.getValueType(); |
| if (VT.isVector() || !VT.isInteger()) |
| return SDValue(); |
| |
| // If operation type is 'undesirable', e.g. i16 on x86, consider |
| // promoting it. |
| unsigned Opc = Op.getOpcode(); |
| if (TLI.isTypeDesirableForOp(Opc, VT)) |
| return SDValue(); |
| |
| EVT PVT = VT; |
| // Consult target whether it is a good idea to promote this operation and |
| // what's the right type to promote it to. |
| if (TLI.IsDesirableToPromoteOp(Op, PVT)) { |
| assert(PVT != VT && "Don't know what type to promote to!"); |
| |
| bool Replace = false; |
| SDValue N0 = Op.getOperand(0); |
| if (Opc == ISD::SRA) |
| N0 = SExtPromoteOperand(Op.getOperand(0), PVT); |
| else if (Opc == ISD::SRL) |
| N0 = ZExtPromoteOperand(Op.getOperand(0), PVT); |
| else |
| N0 = PromoteOperand(N0, PVT, Replace); |
| if (N0.getNode() == 0) |
| return SDValue(); |
| |
| AddToWorkList(N0.getNode()); |
| if (Replace) |
| ReplaceLoadWithPromotedLoad(Op.getOperand(0).getNode(), N0.getNode()); |
| |
| DEBUG(dbgs() << "\nPromoting "; |
| Op.getNode()->dump(&DAG)); |
| DebugLoc dl = Op.getDebugLoc(); |
| return DAG.getNode(ISD::TRUNCATE, dl, VT, |
| DAG.getNode(Opc, dl, PVT, N0, Op.getOperand(1))); |
| } |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::PromoteExtend(SDValue Op) { |
| if (!LegalOperations) |
| return SDValue(); |
| |
| EVT VT = Op.getValueType(); |
| if (VT.isVector() || !VT.isInteger()) |
| return SDValue(); |
| |
| // If operation type is 'undesirable', e.g. i16 on x86, consider |
| // promoting it. |
| unsigned Opc = Op.getOpcode(); |
| if (TLI.isTypeDesirableForOp(Opc, VT)) |
| return SDValue(); |
| |
| EVT PVT = VT; |
| // Consult target whether it is a good idea to promote this operation and |
| // what's the right type to promote it to. |
| if (TLI.IsDesirableToPromoteOp(Op, PVT)) { |
| assert(PVT != VT && "Don't know what type to promote to!"); |
| // fold (aext (aext x)) -> (aext x) |
| // fold (aext (zext x)) -> (zext x) |
| // fold (aext (sext x)) -> (sext x) |
| DEBUG(dbgs() << "\nPromoting "; |
| Op.getNode()->dump(&DAG)); |
| return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), VT, Op.getOperand(0)); |
| } |
| return SDValue(); |
| } |
| |
| bool DAGCombiner::PromoteLoad(SDValue Op) { |
| if (!LegalOperations) |
| return false; |
| |
| EVT VT = Op.getValueType(); |
| if (VT.isVector() || !VT.isInteger()) |
| return false; |
| |
| // If operation type is 'undesirable', e.g. i16 on x86, consider |
| // promoting it. |
| unsigned Opc = Op.getOpcode(); |
| if (TLI.isTypeDesirableForOp(Opc, VT)) |
| return false; |
| |
| EVT PVT = VT; |
| // Consult target whether it is a good idea to promote this operation and |
| // what's the right type to promote it to. |
| if (TLI.IsDesirableToPromoteOp(Op, PVT)) { |
| assert(PVT != VT && "Don't know what type to promote to!"); |
| |
| DebugLoc dl = Op.getDebugLoc(); |
| SDNode *N = Op.getNode(); |
| LoadSDNode *LD = cast<LoadSDNode>(N); |
| EVT MemVT = LD->getMemoryVT(); |
| ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD) |
| ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD |
| : ISD::EXTLOAD) |
| : LD->getExtensionType(); |
| SDValue NewLD = DAG.getExtLoad(ExtType, dl, PVT, |
| LD->getChain(), LD->getBasePtr(), |
| LD->getPointerInfo(), |
| MemVT, LD->isVolatile(), |
| LD->isNonTemporal(), LD->getAlignment()); |
| SDValue Result = DAG.getNode(ISD::TRUNCATE, dl, VT, NewLD); |
| |
| DEBUG(dbgs() << "\nPromoting "; |
| N->dump(&DAG); |
| dbgs() << "\nTo: "; |
| Result.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), NewLD.getValue(1)); |
| removeFromWorkList(N); |
| DAG.DeleteNode(N); |
| AddToWorkList(Result.getNode()); |
| return true; |
| } |
| return false; |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Main DAG Combiner implementation |
| //===----------------------------------------------------------------------===// |
| |
| void DAGCombiner::Run(CombineLevel AtLevel) { |
| // set the instance variables, so that the various visit routines may use it. |
| Level = AtLevel; |
| LegalOperations = Level >= AfterLegalizeVectorOps; |
| LegalTypes = Level >= AfterLegalizeTypes; |
| |
| // Add all the dag nodes to the worklist. |
| for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(), |
| E = DAG.allnodes_end(); I != E; ++I) |
| AddToWorkList(I); |
| |
| // Create a dummy node (which is not added to allnodes), that adds a reference |
| // to the root node, preventing it from being deleted, and tracking any |
| // changes of the root. |
| HandleSDNode Dummy(DAG.getRoot()); |
| |
| // The root of the dag may dangle to deleted nodes until the dag combiner is |
| // done. Set it to null to avoid confusion. |
| DAG.setRoot(SDValue()); |
| |
| // while the worklist isn't empty, find a node and |
| // try and combine it. |
| while (!WorkListContents.empty()) { |
| SDNode *N; |
| // The WorkListOrder holds the SDNodes in order, but it may contain duplicates. |
| // In order to avoid a linear scan, we use a set (O(log N)) to hold what the |
| // worklist *should* contain, and check the node we want to visit is should |
| // actually be visited. |
| do { |
| N = WorkListOrder.pop_back_val(); |
| } while (!WorkListContents.erase(N)); |
| |
| // If N has no uses, it is dead. Make sure to revisit all N's operands once |
| // N is deleted from the DAG, since they too may now be dead or may have a |
| // reduced number of uses, allowing other xforms. |
| if (N->use_empty() && N != &Dummy) { |
| for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) |
| AddToWorkList(N->getOperand(i).getNode()); |
| |
| DAG.DeleteNode(N); |
| continue; |
| } |
| |
| SDValue RV = combine(N); |
| |
| if (RV.getNode() == 0) |
| continue; |
| |
| ++NodesCombined; |
| |
| // If we get back the same node we passed in, rather than a new node or |
| // zero, we know that the node must have defined multiple values and |
| // CombineTo was used. Since CombineTo takes care of the worklist |
| // mechanics for us, we have no work to do in this case. |
| if (RV.getNode() == N) |
| continue; |
| |
| assert(N->getOpcode() != ISD::DELETED_NODE && |
| RV.getNode()->getOpcode() != ISD::DELETED_NODE && |
| "Node was deleted but visit returned new node!"); |
| |
| DEBUG(dbgs() << "\nReplacing.3 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith: "; |
| RV.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| |
| // Transfer debug value. |
| DAG.TransferDbgValues(SDValue(N, 0), RV); |
| WorkListRemover DeadNodes(*this); |
| if (N->getNumValues() == RV.getNode()->getNumValues()) |
| DAG.ReplaceAllUsesWith(N, RV.getNode()); |
| else { |
| assert(N->getValueType(0) == RV.getValueType() && |
| N->getNumValues() == 1 && "Type mismatch"); |
| SDValue OpV = RV; |
| DAG.ReplaceAllUsesWith(N, &OpV); |
| } |
| |
| // Push the new node and any users onto the worklist |
| AddToWorkList(RV.getNode()); |
| AddUsersToWorkList(RV.getNode()); |
| |
| // Add any uses of the old node to the worklist in case this node is the |
| // last one that uses them. They may become dead after this node is |
| // deleted. |
| for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) |
| AddToWorkList(N->getOperand(i).getNode()); |
| |
| // Finally, if the node is now dead, remove it from the graph. The node |
| // may not be dead if the replacement process recursively simplified to |
| // something else needing this node. |
| if (N->use_empty()) { |
| // Nodes can be reintroduced into the worklist. Make sure we do not |
| // process a node that has been replaced. |
| removeFromWorkList(N); |
| |
| // Finally, since the node is now dead, remove it from the graph. |
| DAG.DeleteNode(N); |
| } |
| } |
| |
| // If the root changed (e.g. it was a dead load, update the root). |
| DAG.setRoot(Dummy.getValue()); |
| DAG.RemoveDeadNodes(); |
| } |
| |
| SDValue DAGCombiner::visit(SDNode *N) { |
| switch (N->getOpcode()) { |
| default: break; |
| case ISD::TokenFactor: return visitTokenFactor(N); |
| case ISD::MERGE_VALUES: return visitMERGE_VALUES(N); |
| case ISD::ADD: return visitADD(N); |
| case ISD::SUB: return visitSUB(N); |
| case ISD::ADDC: return visitADDC(N); |
| case ISD::SUBC: return visitSUBC(N); |
| case ISD::ADDE: return visitADDE(N); |
| case ISD::SUBE: return visitSUBE(N); |
| case ISD::MUL: return visitMUL(N); |
| case ISD::SDIV: return visitSDIV(N); |
| case ISD::UDIV: return visitUDIV(N); |
| case ISD::SREM: return visitSREM(N); |
| case ISD::UREM: return visitUREM(N); |
| case ISD::MULHU: return visitMULHU(N); |
| case ISD::MULHS: return visitMULHS(N); |
| case ISD::SMUL_LOHI: return visitSMUL_LOHI(N); |
| case ISD::UMUL_LOHI: return visitUMUL_LOHI(N); |
| case ISD::SMULO: return visitSMULO(N); |
| case ISD::UMULO: return visitUMULO(N); |
| case ISD::SDIVREM: return visitSDIVREM(N); |
| case ISD::UDIVREM: return visitUDIVREM(N); |
| case ISD::AND: return visitAND(N); |
| case ISD::OR: return visitOR(N); |
| case ISD::XOR: return visitXOR(N); |
| case ISD::SHL: return visitSHL(N); |
| case ISD::SRA: return visitSRA(N); |
| case ISD::SRL: return visitSRL(N); |
| case ISD::CTLZ: return visitCTLZ(N); |
| case ISD::CTLZ_ZERO_UNDEF: return visitCTLZ_ZERO_UNDEF(N); |
| case ISD::CTTZ: return visitCTTZ(N); |
| case ISD::CTTZ_ZERO_UNDEF: return visitCTTZ_ZERO_UNDEF(N); |
| case ISD::CTPOP: return visitCTPOP(N); |
| case ISD::SELECT: return visitSELECT(N); |
| case ISD::SELECT_CC: return visitSELECT_CC(N); |
| case ISD::SETCC: return visitSETCC(N); |
| case ISD::SIGN_EXTEND: return visitSIGN_EXTEND(N); |
| case ISD::ZERO_EXTEND: return visitZERO_EXTEND(N); |
| case ISD::ANY_EXTEND: return visitANY_EXTEND(N); |
| case ISD::SIGN_EXTEND_INREG: return visitSIGN_EXTEND_INREG(N); |
| case ISD::TRUNCATE: return visitTRUNCATE(N); |
| case ISD::BITCAST: return visitBITCAST(N); |
| case ISD::BUILD_PAIR: return visitBUILD_PAIR(N); |
| case ISD::FADD: return visitFADD(N); |
| case ISD::FSUB: return visitFSUB(N); |
| case ISD::FMUL: return visitFMUL(N); |
| case ISD::FMA: return visitFMA(N); |
| case ISD::FDIV: return visitFDIV(N); |
| case ISD::FREM: return visitFREM(N); |
| case ISD::FCOPYSIGN: return visitFCOPYSIGN(N); |
| case ISD::SINT_TO_FP: return visitSINT_TO_FP(N); |
| case ISD::UINT_TO_FP: return visitUINT_TO_FP(N); |
| case ISD::FP_TO_SINT: return visitFP_TO_SINT(N); |
| case ISD::FP_TO_UINT: return visitFP_TO_UINT(N); |
| case ISD::FP_ROUND: return visitFP_ROUND(N); |
| case ISD::FP_ROUND_INREG: return visitFP_ROUND_INREG(N); |
| case ISD::FP_EXTEND: return visitFP_EXTEND(N); |
| case ISD::FNEG: return visitFNEG(N); |
| case ISD::FABS: return visitFABS(N); |
| case ISD::FFLOOR: return visitFFLOOR(N); |
| case ISD::FCEIL: return visitFCEIL(N); |
| case ISD::FTRUNC: return visitFTRUNC(N); |
| case ISD::BRCOND: return visitBRCOND(N); |
| case ISD::BR_CC: return visitBR_CC(N); |
| case ISD::LOAD: return visitLOAD(N); |
| case ISD::STORE: return visitSTORE(N); |
| case ISD::INSERT_VECTOR_ELT: return visitINSERT_VECTOR_ELT(N); |
| case ISD::EXTRACT_VECTOR_ELT: return visitEXTRACT_VECTOR_ELT(N); |
| case ISD::BUILD_VECTOR: return visitBUILD_VECTOR(N); |
| case ISD::CONCAT_VECTORS: return visitCONCAT_VECTORS(N); |
| case ISD::EXTRACT_SUBVECTOR: return visitEXTRACT_SUBVECTOR(N); |
| case ISD::VECTOR_SHUFFLE: return visitVECTOR_SHUFFLE(N); |
| case ISD::MEMBARRIER: return visitMEMBARRIER(N); |
| } |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::combine(SDNode *N) { |
| SDValue RV = visit(N); |
| |
| // If nothing happened, try a target-specific DAG combine. |
| if (RV.getNode() == 0) { |
| assert(N->getOpcode() != ISD::DELETED_NODE && |
| "Node was deleted but visit returned NULL!"); |
| |
| if (N->getOpcode() >= ISD::BUILTIN_OP_END || |
| TLI.hasTargetDAGCombine((ISD::NodeType)N->getOpcode())) { |
| |
| // Expose the DAG combiner to the target combiner impls. |
| TargetLowering::DAGCombinerInfo |
| DagCombineInfo(DAG, Level, false, this); |
| |
| RV = TLI.PerformDAGCombine(N, DagCombineInfo); |
| } |
| } |
| |
| // If nothing happened still, try promoting the operation. |
| if (RV.getNode() == 0) { |
| switch (N->getOpcode()) { |
| default: break; |
| case ISD::ADD: |
| case ISD::SUB: |
| case ISD::MUL: |
| case ISD::AND: |
| case ISD::OR: |
| case ISD::XOR: |
| RV = PromoteIntBinOp(SDValue(N, 0)); |
| break; |
| case ISD::SHL: |
| case ISD::SRA: |
| case ISD::SRL: |
| RV = PromoteIntShiftOp(SDValue(N, 0)); |
| break; |
| case ISD::SIGN_EXTEND: |
| case ISD::ZERO_EXTEND: |
| case ISD::ANY_EXTEND: |
| RV = PromoteExtend(SDValue(N, 0)); |
| break; |
| case ISD::LOAD: |
| if (PromoteLoad(SDValue(N, 0))) |
| RV = SDValue(N, 0); |
| break; |
| } |
| } |
| |
| // If N is a commutative binary node, try commuting it to enable more |
| // sdisel CSE. |
| if (RV.getNode() == 0 && |
| SelectionDAG::isCommutativeBinOp(N->getOpcode()) && |
| N->getNumValues() == 1) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| |
| // Constant operands are canonicalized to RHS. |
| if (isa<ConstantSDNode>(N0) || !isa<ConstantSDNode>(N1)) { |
| SDValue Ops[] = { N1, N0 }; |
| SDNode *CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(), |
| Ops, 2); |
| if (CSENode) |
| return SDValue(CSENode, 0); |
| } |
| } |
| |
| return RV; |
| } |
| |
| /// getInputChainForNode - Given a node, return its input chain if it has one, |
| /// otherwise return a null sd operand. |
| static SDValue getInputChainForNode(SDNode *N) { |
| if (unsigned NumOps = N->getNumOperands()) { |
| if (N->getOperand(0).getValueType() == MVT::Other) |
| return N->getOperand(0); |
| else if (N->getOperand(NumOps-1).getValueType() == MVT::Other) |
| return N->getOperand(NumOps-1); |
| for (unsigned i = 1; i < NumOps-1; ++i) |
| if (N->getOperand(i).getValueType() == MVT::Other) |
| return N->getOperand(i); |
| } |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitTokenFactor(SDNode *N) { |
| // If N has two operands, where one has an input chain equal to the other, |
| // the 'other' chain is redundant. |
| if (N->getNumOperands() == 2) { |
| if (getInputChainForNode(N->getOperand(0).getNode()) == N->getOperand(1)) |
| return N->getOperand(0); |
| if (getInputChainForNode(N->getOperand(1).getNode()) == N->getOperand(0)) |
| return N->getOperand(1); |
| } |
| |
| SmallVector<SDNode *, 8> TFs; // List of token factors to visit. |
| SmallVector<SDValue, 8> Ops; // Ops for replacing token factor. |
| SmallPtrSet<SDNode*, 16> SeenOps; |
| bool Changed = false; // If we should replace this token factor. |
| |
| // Start out with this token factor. |
| TFs.push_back(N); |
| |
| // Iterate through token factors. The TFs grows when new token factors are |
| // encountered. |
| for (unsigned i = 0; i < TFs.size(); ++i) { |
| SDNode *TF = TFs[i]; |
| |
| // Check each of the operands. |
| for (unsigned i = 0, ie = TF->getNumOperands(); i != ie; ++i) { |
| SDValue Op = TF->getOperand(i); |
| |
| switch (Op.getOpcode()) { |
| case ISD::EntryToken: |
| // Entry tokens don't need to be added to the list. They are |
| // rededundant. |
| Changed = true; |
| break; |
| |
| case ISD::TokenFactor: |
| if (Op.hasOneUse() && |
| std::find(TFs.begin(), TFs.end(), Op.getNode()) == TFs.end()) { |
| // Queue up for processing. |
| TFs.push_back(Op.getNode()); |
| // Clean up in case the token factor is removed. |
| AddToWorkList(Op.getNode()); |
| Changed = true; |
| break; |
| } |
| // Fall thru |
| |
| default: |
| // Only add if it isn't already in the list. |
| if (SeenOps.insert(Op.getNode())) |
| Ops.push_back(Op); |
| else |
| Changed = true; |
| break; |
| } |
| } |
| } |
| |
| SDValue Result; |
| |
| // If we've change things around then replace token factor. |
| if (Changed) { |
| if (Ops.empty()) { |
| // The entry token is the only possible outcome. |
| Result = DAG.getEntryNode(); |
| } else { |
| // New and improved token factor. |
| Result = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), |
| MVT::Other, &Ops[0], Ops.size()); |
| } |
| |
| // Don't add users to work list. |
| return CombineTo(N, Result, false); |
| } |
| |
| return Result; |
| } |
| |
| /// MERGE_VALUES can always be eliminated. |
| SDValue DAGCombiner::visitMERGE_VALUES(SDNode *N) { |
| WorkListRemover DeadNodes(*this); |
| // Replacing results may cause a different MERGE_VALUES to suddenly |
| // be CSE'd with N, and carry its uses with it. Iterate until no |
| // uses remain, to ensure that the node can be safely deleted. |
| // First add the users of this node to the work list so that they |
| // can be tried again once they have new operands. |
| AddUsersToWorkList(N); |
| do { |
| for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, i), N->getOperand(i)); |
| } while (!N->use_empty()); |
| removeFromWorkList(N); |
| DAG.DeleteNode(N); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| static |
| SDValue combineShlAddConstant(DebugLoc DL, SDValue N0, SDValue N1, |
| SelectionDAG &DAG) { |
| EVT VT = N0.getValueType(); |
| SDValue N00 = N0.getOperand(0); |
| SDValue N01 = N0.getOperand(1); |
| ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N01); |
| |
| if (N01C && N00.getOpcode() == ISD::ADD && N00.getNode()->hasOneUse() && |
| isa<ConstantSDNode>(N00.getOperand(1))) { |
| // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), ) |
| N0 = DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT, |
| DAG.getNode(ISD::SHL, N00.getDebugLoc(), VT, |
| N00.getOperand(0), N01), |
| DAG.getNode(ISD::SHL, N01.getDebugLoc(), VT, |
| N00.getOperand(1), N01)); |
| return DAG.getNode(ISD::ADD, DL, VT, N0, N1); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitADD(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| |
| // fold (add x, 0) -> x, vector edition |
| if (ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N0; |
| if (ISD::isBuildVectorAllZeros(N0.getNode())) |
| return N1; |
| } |
| |
| // fold (add x, undef) -> undef |
| if (N0.getOpcode() == ISD::UNDEF) |
| return N0; |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| // fold (add c1, c2) -> c1+c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::ADD, VT, N0C, N1C); |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1, N0); |
| // fold (add x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // fold (add Sym, c) -> Sym+c |
| if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0)) |
| if (!LegalOperations && TLI.isOffsetFoldingLegal(GA) && N1C && |
| GA->getOpcode() == ISD::GlobalAddress) |
| return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT, |
| GA->getOffset() + |
| (uint64_t)N1C->getSExtValue()); |
| // fold ((c1-A)+c2) -> (c1+c2)-A |
| if (N1C && N0.getOpcode() == ISD::SUB) |
| if (ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getOperand(0))) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getConstant(N1C->getAPIntValue()+ |
| N0C->getAPIntValue(), VT), |
| N0.getOperand(1)); |
| // reassociate add |
| SDValue RADD = ReassociateOps(ISD::ADD, N->getDebugLoc(), N0, N1); |
| if (RADD.getNode() != 0) |
| return RADD; |
| // fold ((0-A) + B) -> B-A |
| if (N0.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N0.getOperand(0)) && |
| cast<ConstantSDNode>(N0.getOperand(0))->isNullValue()) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1, N0.getOperand(1)); |
| // fold (A + (0-B)) -> A-B |
| if (N1.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N1.getOperand(0)) && |
| cast<ConstantSDNode>(N1.getOperand(0))->isNullValue()) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, N1.getOperand(1)); |
| // fold (A+(B-A)) -> B |
| if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(1)) |
| return N1.getOperand(0); |
| // fold ((B-A)+A) -> B |
| if (N0.getOpcode() == ISD::SUB && N1 == N0.getOperand(1)) |
| return N0.getOperand(0); |
| // fold (A+(B-(A+C))) to (B-C) |
| if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD && |
| N0 == N1.getOperand(1).getOperand(0)) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0), |
| N1.getOperand(1).getOperand(1)); |
| // fold (A+(B-(C+A))) to (B-C) |
| if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD && |
| N0 == N1.getOperand(1).getOperand(1)) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0), |
| N1.getOperand(1).getOperand(0)); |
| // fold (A+((B-A)+or-C)) to (B+or-C) |
| if ((N1.getOpcode() == ISD::SUB || N1.getOpcode() == ISD::ADD) && |
| N1.getOperand(0).getOpcode() == ISD::SUB && |
| N0 == N1.getOperand(0).getOperand(1)) |
| return DAG.getNode(N1.getOpcode(), N->getDebugLoc(), VT, |
| N1.getOperand(0).getOperand(0), N1.getOperand(1)); |
| |
| // fold (A-B)+(C-D) to (A+C)-(B+D) when A or C is constant |
| if (N0.getOpcode() == ISD::SUB && N1.getOpcode() == ISD::SUB) { |
| SDValue N00 = N0.getOperand(0); |
| SDValue N01 = N0.getOperand(1); |
| SDValue N10 = N1.getOperand(0); |
| SDValue N11 = N1.getOperand(1); |
| |
| if (isa<ConstantSDNode>(N00) || isa<ConstantSDNode>(N10)) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT, N00, N10), |
| DAG.getNode(ISD::ADD, N1.getDebugLoc(), VT, N01, N11)); |
| } |
| |
| if (!VT.isVector() && SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| // fold (a+b) -> (a|b) iff a and b share no bits. |
| if (VT.isInteger() && !VT.isVector()) { |
| APInt LHSZero, LHSOne; |
| APInt RHSZero, RHSOne; |
| DAG.ComputeMaskedBits(N0, LHSZero, LHSOne); |
| |
| if (LHSZero.getBoolValue()) { |
| DAG.ComputeMaskedBits(N1, RHSZero, RHSOne); |
| |
| // If all possibly-set bits on the LHS are clear on the RHS, return an OR. |
| // If all possibly-set bits on the RHS are clear on the LHS, return an OR. |
| if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero) |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1); |
| } |
| } |
| |
| // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), ) |
| if (N0.getOpcode() == ISD::SHL && N0.getNode()->hasOneUse()) { |
| SDValue Result = combineShlAddConstant(N->getDebugLoc(), N0, N1, DAG); |
| if (Result.getNode()) return Result; |
| } |
| if (N1.getOpcode() == ISD::SHL && N1.getNode()->hasOneUse()) { |
| SDValue Result = combineShlAddConstant(N->getDebugLoc(), N1, N0, DAG); |
| if (Result.getNode()) return Result; |
| } |
| |
| // fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n)) |
| if (N1.getOpcode() == ISD::SHL && |
| N1.getOperand(0).getOpcode() == ISD::SUB) |
| if (ConstantSDNode *C = |
| dyn_cast<ConstantSDNode>(N1.getOperand(0).getOperand(0))) |
| if (C->getAPIntValue() == 0) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, |
| DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, |
| N1.getOperand(0).getOperand(1), |
| N1.getOperand(1))); |
| if (N0.getOpcode() == ISD::SHL && |
| N0.getOperand(0).getOpcode() == ISD::SUB) |
| if (ConstantSDNode *C = |
| dyn_cast<ConstantSDNode>(N0.getOperand(0).getOperand(0))) |
| if (C->getAPIntValue() == 0) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1, |
| DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, |
| N0.getOperand(0).getOperand(1), |
| N0.getOperand(1))); |
| |
| if (N1.getOpcode() == ISD::AND) { |
| SDValue AndOp0 = N1.getOperand(0); |
| ConstantSDNode *AndOp1 = dyn_cast<ConstantSDNode>(N1->getOperand(1)); |
| unsigned NumSignBits = DAG.ComputeNumSignBits(AndOp0); |
| unsigned DestBits = VT.getScalarType().getSizeInBits(); |
| |
| // (add z, (and (sbbl x, x), 1)) -> (sub z, (sbbl x, x)) |
| // and similar xforms where the inner op is either ~0 or 0. |
| if (NumSignBits == DestBits && AndOp1 && AndOp1->isOne()) { |
| DebugLoc DL = N->getDebugLoc(); |
| return DAG.getNode(ISD::SUB, DL, VT, N->getOperand(0), AndOp0); |
| } |
| } |
| |
| // add (sext i1), X -> sub X, (zext i1) |
| if (N0.getOpcode() == ISD::SIGN_EXTEND && |
| N0.getOperand(0).getValueType() == MVT::i1 && |
| !TLI.isOperationLegal(ISD::SIGN_EXTEND, MVT::i1)) { |
| DebugLoc DL = N->getDebugLoc(); |
| SDValue ZExt = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0)); |
| return DAG.getNode(ISD::SUB, DL, VT, N1, ZExt); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitADDC(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| |
| // If the flag result is dead, turn this into an ADD. |
| if (!N->hasAnyUseOfValue(1)) |
| return CombineTo(N, DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, N1), |
| DAG.getNode(ISD::CARRY_FALSE, |
| N->getDebugLoc(), MVT::Glue)); |
| |
| // canonicalize constant to RHS. |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N1, N0); |
| |
| // fold (addc x, 0) -> x + no carry out |
| if (N1C && N1C->isNullValue()) |
| return CombineTo(N, N0, DAG.getNode(ISD::CARRY_FALSE, |
| N->getDebugLoc(), MVT::Glue)); |
| |
| // fold (addc a, b) -> (or a, b), CARRY_FALSE iff a and b share no bits. |
| APInt LHSZero, LHSOne; |
| APInt RHSZero, RHSOne; |
| DAG.ComputeMaskedBits(N0, LHSZero, LHSOne); |
| |
| if (LHSZero.getBoolValue()) { |
| DAG.ComputeMaskedBits(N1, RHSZero, RHSOne); |
| |
| // If all possibly-set bits on the LHS are clear on the RHS, return an OR. |
| // If all possibly-set bits on the RHS are clear on the LHS, return an OR. |
| if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero) |
| return CombineTo(N, DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1), |
| DAG.getNode(ISD::CARRY_FALSE, |
| N->getDebugLoc(), MVT::Glue)); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitADDE(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue CarryIn = N->getOperand(2); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::ADDE, N->getDebugLoc(), N->getVTList(), |
| N1, N0, CarryIn); |
| |
| // fold (adde x, y, false) -> (addc x, y) |
| if (CarryIn.getOpcode() == ISD::CARRY_FALSE) |
| return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N0, N1); |
| |
| return SDValue(); |
| } |
| |
| // Since it may not be valid to emit a fold to zero for vector initializers |
| // check if we can before folding. |
| static SDValue tryFoldToZero(DebugLoc DL, const TargetLowering &TLI, EVT VT, |
| SelectionDAG &DAG, bool LegalOperations) { |
| if (!VT.isVector()) { |
| return DAG.getConstant(0, VT); |
| } |
| if (!LegalOperations || TLI.isOperationLegal(ISD::BUILD_VECTOR, VT)) { |
| // Produce a vector of zeros. |
| SDValue El = DAG.getConstant(0, VT.getVectorElementType()); |
| std::vector<SDValue> Ops(VT.getVectorNumElements(), El); |
| return DAG.getNode(ISD::BUILD_VECTOR, DL, VT, |
| &Ops[0], Ops.size()); |
| } |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSUB(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode()); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode()); |
| ConstantSDNode *N1C1 = N1.getOpcode() != ISD::ADD ? 0 : |
| dyn_cast<ConstantSDNode>(N1.getOperand(1).getNode()); |
| EVT VT = N0.getValueType(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| |
| // fold (sub x, 0) -> x, vector edition |
| if (ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N0; |
| } |
| |
| // fold (sub x, x) -> 0 |
| // FIXME: Refactor this and xor and other similar operations together. |
| if (N0 == N1) |
| return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations); |
| // fold (sub c1, c2) -> c1-c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::SUB, VT, N0C, N1C); |
| // fold (sub x, c) -> (add x, -c) |
| if (N1C) |
| return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(-N1C->getAPIntValue(), VT)); |
| // Canonicalize (sub -1, x) -> ~x, i.e. (xor x, -1) |
| if (N0C && N0C->isAllOnesValue()) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0); |
| // fold A-(A-B) -> B |
| if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(0)) |
| return N1.getOperand(1); |
| // fold (A+B)-A -> B |
| if (N0.getOpcode() == ISD::ADD && N0.getOperand(0) == N1) |
| return N0.getOperand(1); |
| // fold (A+B)-B -> A |
| if (N0.getOpcode() == ISD::ADD && N0.getOperand(1) == N1) |
| return N0.getOperand(0); |
| // fold C2-(A+C1) -> (C2-C1)-A |
| if (N1.getOpcode() == ISD::ADD && N0C && N1C1) { |
| SDValue NewC = DAG.getConstant(N0C->getAPIntValue() - N1C1->getAPIntValue(), |
| VT); |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, NewC, |
| N1.getOperand(0)); |
| } |
| // fold ((A+(B+or-C))-B) -> A+or-C |
| if (N0.getOpcode() == ISD::ADD && |
| (N0.getOperand(1).getOpcode() == ISD::SUB || |
| N0.getOperand(1).getOpcode() == ISD::ADD) && |
| N0.getOperand(1).getOperand(0) == N1) |
| return DAG.getNode(N0.getOperand(1).getOpcode(), N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1).getOperand(1)); |
| // fold ((A+(C+B))-B) -> A+C |
| if (N0.getOpcode() == ISD::ADD && |
| N0.getOperand(1).getOpcode() == ISD::ADD && |
| N0.getOperand(1).getOperand(1) == N1) |
| return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1).getOperand(0)); |
| // fold ((A-(B-C))-C) -> A-B |
| if (N0.getOpcode() == ISD::SUB && |
| N0.getOperand(1).getOpcode() == ISD::SUB && |
| N0.getOperand(1).getOperand(1) == N1) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1).getOperand(0)); |
| |
| // If either operand of a sub is undef, the result is undef |
| if (N0.getOpcode() == ISD::UNDEF) |
| return N0; |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| |
| // If the relocation model supports it, consider symbol offsets. |
| if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0)) |
| if (!LegalOperations && TLI.isOffsetFoldingLegal(GA)) { |
| // fold (sub Sym, c) -> Sym-c |
| if (N1C && GA->getOpcode() == ISD::GlobalAddress) |
| return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT, |
| GA->getOffset() - |
| (uint64_t)N1C->getSExtValue()); |
| // fold (sub Sym+c1, Sym+c2) -> c1-c2 |
| if (GlobalAddressSDNode *GB = dyn_cast<GlobalAddressSDNode>(N1)) |
| if (GA->getGlobal() == GB->getGlobal()) |
| return DAG.getConstant((uint64_t)GA->getOffset() - GB->getOffset(), |
| VT); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSUBC(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| |
| // If the flag result is dead, turn this into an SUB. |
| if (!N->hasAnyUseOfValue(1)) |
| return CombineTo(N, DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, N1), |
| DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(), |
| MVT::Glue)); |
| |
| // fold (subc x, x) -> 0 + no borrow |
| if (N0 == N1) |
| return CombineTo(N, DAG.getConstant(0, VT), |
| DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(), |
| MVT::Glue)); |
| |
| // fold (subc x, 0) -> x + no borrow |
| if (N1C && N1C->isNullValue()) |
| return CombineTo(N, N0, DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(), |
| MVT::Glue)); |
| |
| // Canonicalize (sub -1, x) -> ~x, i.e. (xor x, -1) + no borrow |
| if (N0C && N0C->isAllOnesValue()) |
| return CombineTo(N, DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0), |
| DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(), |
| MVT::Glue)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSUBE(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue CarryIn = N->getOperand(2); |
| |
| // fold (sube x, y, false) -> (subc x, y) |
| if (CarryIn.getOpcode() == ISD::CARRY_FALSE) |
| return DAG.getNode(ISD::SUBC, N->getDebugLoc(), N->getVTList(), N0, N1); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitMUL(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (mul x, undef) -> 0 |
| if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // fold (mul c1, c2) -> c1*c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::MUL, VT, N0C, N1C); |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, N1, N0); |
| // fold (mul x, 0) -> 0 |
| if (N1C && N1C->isNullValue()) |
| return N1; |
| // fold (mul x, -1) -> 0-x |
| if (N1C && N1C->isAllOnesValue()) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getConstant(0, VT), N0); |
| // fold (mul x, (1 << c)) -> x << c |
| if (N1C && N1C->getAPIntValue().isPowerOf2()) |
| return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(N1C->getAPIntValue().logBase2(), |
| getShiftAmountTy(N0.getValueType()))); |
| // fold (mul x, -(1 << c)) -> -(x << c) or (-x) << c |
| if (N1C && (-N1C->getAPIntValue()).isPowerOf2()) { |
| unsigned Log2Val = (-N1C->getAPIntValue()).logBase2(); |
| // FIXME: If the input is something that is easily negated (e.g. a |
| // single-use add), we should put the negate there. |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getConstant(0, VT), |
| DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(Log2Val, |
| getShiftAmountTy(N0.getValueType())))); |
| } |
| // (mul (shl X, c1), c2) -> (mul X, c2 << c1) |
| if (N1C && N0.getOpcode() == ISD::SHL && |
| isa<ConstantSDNode>(N0.getOperand(1))) { |
| SDValue C3 = DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, |
| N1, N0.getOperand(1)); |
| AddToWorkList(C3.getNode()); |
| return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, |
| N0.getOperand(0), C3); |
| } |
| |
| // Change (mul (shl X, C), Y) -> (shl (mul X, Y), C) when the shift has one |
| // use. |
| { |
| SDValue Sh(0,0), Y(0,0); |
| // Check for both (mul (shl X, C), Y) and (mul Y, (shl X, C)). |
| if (N0.getOpcode() == ISD::SHL && isa<ConstantSDNode>(N0.getOperand(1)) && |
| N0.getNode()->hasOneUse()) { |
| Sh = N0; Y = N1; |
| } else if (N1.getOpcode() == ISD::SHL && |
| isa<ConstantSDNode>(N1.getOperand(1)) && |
| N1.getNode()->hasOneUse()) { |
| Sh = N1; Y = N0; |
| } |
| |
| if (Sh.getNode()) { |
| SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, |
| Sh.getOperand(0), Y); |
| return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, |
| Mul, Sh.getOperand(1)); |
| } |
| } |
| |
| // fold (mul (add x, c1), c2) -> (add (mul x, c2), c1*c2) |
| if (N1C && N0.getOpcode() == ISD::ADD && N0.getNode()->hasOneUse() && |
| isa<ConstantSDNode>(N0.getOperand(1))) |
| return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, |
| DAG.getNode(ISD::MUL, N0.getDebugLoc(), VT, |
| N0.getOperand(0), N1), |
| DAG.getNode(ISD::MUL, N1.getDebugLoc(), VT, |
| N0.getOperand(1), N1)); |
| |
| // reassociate mul |
| SDValue RMUL = ReassociateOps(ISD::MUL, N->getDebugLoc(), N0, N1); |
| if (RMUL.getNode() != 0) |
| return RMUL; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSDIV(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode()); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode()); |
| EVT VT = N->getValueType(0); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (sdiv c1, c2) -> c1/c2 |
| if (N0C && N1C && !N1C->isNullValue()) |
| return DAG.FoldConstantArithmetic(ISD::SDIV, VT, N0C, N1C); |
| // fold (sdiv X, 1) -> X |
| if (N1C && N1C->getAPIntValue() == 1LL) |
| return N0; |
| // fold (sdiv X, -1) -> 0-X |
| if (N1C && N1C->isAllOnesValue()) |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getConstant(0, VT), N0); |
| // If we know the sign bits of both operands are zero, strength reduce to a |
| // udiv instead. Handles (X&15) /s 4 -> X&15 >> 2 |
| if (!VT.isVector()) { |
| if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::UDIV, N->getDebugLoc(), N1.getValueType(), |
| N0, N1); |
| } |
| // fold (sdiv X, pow2) -> simple ops after legalize |
| if (N1C && !N1C->isNullValue() && |
| (N1C->getAPIntValue().isPowerOf2() || |
| (-N1C->getAPIntValue()).isPowerOf2())) { |
| // If dividing by powers of two is cheap, then don't perform the following |
| // fold. |
| if (TLI.isPow2DivCheap()) |
| return SDValue(); |
| |
| unsigned lg2 = N1C->getAPIntValue().countTrailingZeros(); |
| |
| // Splat the sign bit into the register |
| SDValue SGN = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(VT.getSizeInBits()-1, |
| getShiftAmountTy(N0.getValueType()))); |
| AddToWorkList(SGN.getNode()); |
| |
| // Add (N0 < 0) ? abs2 - 1 : 0; |
| SDValue SRL = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, SGN, |
| DAG.getConstant(VT.getSizeInBits() - lg2, |
| getShiftAmountTy(SGN.getValueType()))); |
| SDValue ADD = DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, SRL); |
| AddToWorkList(SRL.getNode()); |
| AddToWorkList(ADD.getNode()); // Divide by pow2 |
| SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, ADD, |
| DAG.getConstant(lg2, getShiftAmountTy(ADD.getValueType()))); |
| |
| // If we're dividing by a positive value, we're done. Otherwise, we must |
| // negate the result. |
| if (N1C->getAPIntValue().isNonNegative()) |
| return SRA; |
| |
| AddToWorkList(SRA.getNode()); |
| return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, |
| DAG.getConstant(0, VT), SRA); |
| } |
| |
| // if integer divide is expensive and we satisfy the requirements, emit an |
| // alternate sequence. |
| if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap()) { |
| SDValue Op = BuildSDIV(N); |
| if (Op.getNode()) return Op; |
| } |
| |
| // undef / X -> 0 |
| if (N0.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // X / undef -> undef |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUDIV(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode()); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode()); |
| EVT VT = N->getValueType(0); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (udiv c1, c2) -> c1/c2 |
| if (N0C && N1C && !N1C->isNullValue()) |
| return DAG.FoldConstantArithmetic(ISD::UDIV, VT, N0C, N1C); |
| // fold (udiv x, (1 << c)) -> x >>u c |
| if (N1C && N1C->getAPIntValue().isPowerOf2()) |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(N1C->getAPIntValue().logBase2(), |
| getShiftAmountTy(N0.getValueType()))); |
| // fold (udiv x, (shl c, y)) -> x >>u (log2(c)+y) iff c is power of 2 |
| if (N1.getOpcode() == ISD::SHL) { |
| if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) { |
| if (SHC->getAPIntValue().isPowerOf2()) { |
| EVT ADDVT = N1.getOperand(1).getValueType(); |
| SDValue Add = DAG.getNode(ISD::ADD, N->getDebugLoc(), ADDVT, |
| N1.getOperand(1), |
| DAG.getConstant(SHC->getAPIntValue() |
| .logBase2(), |
| ADDVT)); |
| AddToWorkList(Add.getNode()); |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, Add); |
| } |
| } |
| } |
| // fold (udiv x, c) -> alternate |
| if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap()) { |
| SDValue Op = BuildUDIV(N); |
| if (Op.getNode()) return Op; |
| } |
| |
| // undef / X -> 0 |
| if (N0.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // X / undef -> undef |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSREM(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| |
| // fold (srem c1, c2) -> c1%c2 |
| if (N0C && N1C && !N1C->isNullValue()) |
| return DAG.FoldConstantArithmetic(ISD::SREM, VT, N0C, N1C); |
| // If we know the sign bits of both operands are zero, strength reduce to a |
| // urem instead. Handles (X & 0x0FFFFFFF) %s 16 -> X&15 |
| if (!VT.isVector()) { |
| if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::UREM, N->getDebugLoc(), VT, N0, N1); |
| } |
| |
| // If X/C can be simplified by the division-by-constant logic, lower |
| // X%C to the equivalent of X-X/C*C. |
| if (N1C && !N1C->isNullValue()) { |
| SDValue Div = DAG.getNode(ISD::SDIV, N->getDebugLoc(), VT, N0, N1); |
| AddToWorkList(Div.getNode()); |
| SDValue OptimizedDiv = combine(Div.getNode()); |
| if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) { |
| SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, |
| OptimizedDiv, N1); |
| SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul); |
| AddToWorkList(Mul.getNode()); |
| return Sub; |
| } |
| } |
| |
| // undef % X -> 0 |
| if (N0.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // X % undef -> undef |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUREM(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| |
| // fold (urem c1, c2) -> c1%c2 |
| if (N0C && N1C && !N1C->isNullValue()) |
| return DAG.FoldConstantArithmetic(ISD::UREM, VT, N0C, N1C); |
| // fold (urem x, pow2) -> (and x, pow2-1) |
| if (N1C && !N1C->isNullValue() && N1C->getAPIntValue().isPowerOf2()) |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, |
| DAG.getConstant(N1C->getAPIntValue()-1,VT)); |
| // fold (urem x, (shl pow2, y)) -> (and x, (add (shl pow2, y), -1)) |
| if (N1.getOpcode() == ISD::SHL) { |
| if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) { |
| if (SHC->getAPIntValue().isPowerOf2()) { |
| SDValue Add = |
| DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1, |
| DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), |
| VT)); |
| AddToWorkList(Add.getNode()); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, Add); |
| } |
| } |
| } |
| |
| // If X/C can be simplified by the division-by-constant logic, lower |
| // X%C to the equivalent of X-X/C*C. |
| if (N1C && !N1C->isNullValue()) { |
| SDValue Div = DAG.getNode(ISD::UDIV, N->getDebugLoc(), VT, N0, N1); |
| AddToWorkList(Div.getNode()); |
| SDValue OptimizedDiv = combine(Div.getNode()); |
| if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) { |
| SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, |
| OptimizedDiv, N1); |
| SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul); |
| AddToWorkList(Mul.getNode()); |
| return Sub; |
| } |
| } |
| |
| // undef % X -> 0 |
| if (N0.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // X % undef -> undef |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitMULHS(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| DebugLoc DL = N->getDebugLoc(); |
| |
| // fold (mulhs x, 0) -> 0 |
| if (N1C && N1C->isNullValue()) |
| return N1; |
| // fold (mulhs x, 1) -> (sra x, size(x)-1) |
| if (N1C && N1C->getAPIntValue() == 1) |
| return DAG.getNode(ISD::SRA, N->getDebugLoc(), N0.getValueType(), N0, |
| DAG.getConstant(N0.getValueType().getSizeInBits() - 1, |
| getShiftAmountTy(N0.getValueType()))); |
| // fold (mulhs x, undef) -> 0 |
| if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| |
| // If the type twice as wide is legal, transform the mulhs to a wider multiply |
| // plus a shift. |
| if (VT.isSimple() && !VT.isVector()) { |
| MVT Simple = VT.getSimpleVT(); |
| unsigned SimpleSize = Simple.getSizeInBits(); |
| EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2); |
| if (TLI.isOperationLegal(ISD::MUL, NewVT)) { |
| N0 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N0); |
| N1 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N1); |
| N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1); |
| N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1, |
| DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType()))); |
| return DAG.getNode(ISD::TRUNCATE, DL, VT, N1); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitMULHU(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| DebugLoc DL = N->getDebugLoc(); |
| |
| // fold (mulhu x, 0) -> 0 |
| if (N1C && N1C->isNullValue()) |
| return N1; |
| // fold (mulhu x, 1) -> 0 |
| if (N1C && N1C->getAPIntValue() == 1) |
| return DAG.getConstant(0, N0.getValueType()); |
| // fold (mulhu x, undef) -> 0 |
| if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| |
| // If the type twice as wide is legal, transform the mulhu to a wider multiply |
| // plus a shift. |
| if (VT.isSimple() && !VT.isVector()) { |
| MVT Simple = VT.getSimpleVT(); |
| unsigned SimpleSize = Simple.getSizeInBits(); |
| EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2); |
| if (TLI.isOperationLegal(ISD::MUL, NewVT)) { |
| N0 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N0); |
| N1 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N1); |
| N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1); |
| N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1, |
| DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType()))); |
| return DAG.getNode(ISD::TRUNCATE, DL, VT, N1); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| /// SimplifyNodeWithTwoResults - Perform optimizations common to nodes that |
| /// compute two values. LoOp and HiOp give the opcodes for the two computations |
| /// that are being performed. Return true if a simplification was made. |
| /// |
| SDValue DAGCombiner::SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp, |
| unsigned HiOp) { |
| // If the high half is not needed, just compute the low half. |
| bool HiExists = N->hasAnyUseOfValue(1); |
| if (!HiExists && |
| (!LegalOperations || |
| TLI.isOperationLegal(LoOp, N->getValueType(0)))) { |
| SDValue Res = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0), |
| N->op_begin(), N->getNumOperands()); |
| return CombineTo(N, Res, Res); |
| } |
| |
| // If the low half is not needed, just compute the high half. |
| bool LoExists = N->hasAnyUseOfValue(0); |
| if (!LoExists && |
| (!LegalOperations || |
| TLI.isOperationLegal(HiOp, N->getValueType(1)))) { |
| SDValue Res = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1), |
| N->op_begin(), N->getNumOperands()); |
| return CombineTo(N, Res, Res); |
| } |
| |
| // If both halves are used, return as it is. |
| if (LoExists && HiExists) |
| return SDValue(); |
| |
| // If the two computed results can be simplified separately, separate them. |
| if (LoExists) { |
| SDValue Lo = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0), |
| N->op_begin(), N->getNumOperands()); |
| AddToWorkList(Lo.getNode()); |
| SDValue LoOpt = combine(Lo.getNode()); |
| if (LoOpt.getNode() && LoOpt.getNode() != Lo.getNode() && |
| (!LegalOperations || |
| TLI.isOperationLegal(LoOpt.getOpcode(), LoOpt.getValueType()))) |
| return CombineTo(N, LoOpt, LoOpt); |
| } |
| |
| if (HiExists) { |
| SDValue Hi = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1), |
| N->op_begin(), N->getNumOperands()); |
| AddToWorkList(Hi.getNode()); |
| SDValue HiOpt = combine(Hi.getNode()); |
| if (HiOpt.getNode() && HiOpt != Hi && |
| (!LegalOperations || |
| TLI.isOperationLegal(HiOpt.getOpcode(), HiOpt.getValueType()))) |
| return CombineTo(N, HiOpt, HiOpt); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSMUL_LOHI(SDNode *N) { |
| SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHS); |
| if (Res.getNode()) return Res; |
| |
| EVT VT = N->getValueType(0); |
| DebugLoc DL = N->getDebugLoc(); |
| |
| // If the type twice as wide is legal, transform the mulhu to a wider multiply |
| // plus a shift. |
| if (VT.isSimple() && !VT.isVector()) { |
| MVT Simple = VT.getSimpleVT(); |
| unsigned SimpleSize = Simple.getSizeInBits(); |
| EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2); |
| if (TLI.isOperationLegal(ISD::MUL, NewVT)) { |
| SDValue Lo = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(0)); |
| SDValue Hi = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(1)); |
| Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi); |
| // Compute the high part as N1. |
| Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo, |
| DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType()))); |
| Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi); |
| // Compute the low part as N0. |
| Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo); |
| return CombineTo(N, Lo, Hi); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUMUL_LOHI(SDNode *N) { |
| SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHU); |
| if (Res.getNode()) return Res; |
| |
| EVT VT = N->getValueType(0); |
| DebugLoc DL = N->getDebugLoc(); |
| |
| // If the type twice as wide is legal, transform the mulhu to a wider multiply |
| // plus a shift. |
| if (VT.isSimple() && !VT.isVector()) { |
| MVT Simple = VT.getSimpleVT(); |
| unsigned SimpleSize = Simple.getSizeInBits(); |
| EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2); |
| if (TLI.isOperationLegal(ISD::MUL, NewVT)) { |
| SDValue Lo = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(0)); |
| SDValue Hi = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(1)); |
| Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi); |
| // Compute the high part as N1. |
| Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo, |
| DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType()))); |
| Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi); |
| // Compute the low part as N0. |
| Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo); |
| return CombineTo(N, Lo, Hi); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSMULO(SDNode *N) { |
| // (smulo x, 2) -> (saddo x, x) |
| if (ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N->getOperand(1))) |
| if (C2->getAPIntValue() == 2) |
| return DAG.getNode(ISD::SADDO, N->getDebugLoc(), N->getVTList(), |
| N->getOperand(0), N->getOperand(0)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUMULO(SDNode *N) { |
| // (umulo x, 2) -> (uaddo x, x) |
| if (ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N->getOperand(1))) |
| if (C2->getAPIntValue() == 2) |
| return DAG.getNode(ISD::UADDO, N->getDebugLoc(), N->getVTList(), |
| N->getOperand(0), N->getOperand(0)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSDIVREM(SDNode *N) { |
| SDValue Res = SimplifyNodeWithTwoResults(N, ISD::SDIV, ISD::SREM); |
| if (Res.getNode()) return Res; |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUDIVREM(SDNode *N) { |
| SDValue Res = SimplifyNodeWithTwoResults(N, ISD::UDIV, ISD::UREM); |
| if (Res.getNode()) return Res; |
| |
| return SDValue(); |
| } |
| |
| /// SimplifyBinOpWithSameOpcodeHands - If this is a binary operator with |
| /// two operands of the same opcode, try to simplify it. |
| SDValue DAGCombiner::SimplifyBinOpWithSameOpcodeHands(SDNode *N) { |
| SDValue N0 = N->getOperand(0), N1 = N->getOperand(1); |
| EVT VT = N0.getValueType(); |
| assert(N0.getOpcode() == N1.getOpcode() && "Bad input!"); |
| |
| // Bail early if none of these transforms apply. |
| if (N0.getNode()->getNumOperands() == 0) return SDValue(); |
| |
| // For each of OP in AND/OR/XOR: |
| // fold (OP (zext x), (zext y)) -> (zext (OP x, y)) |
| // fold (OP (sext x), (sext y)) -> (sext (OP x, y)) |
| // fold (OP (aext x), (aext y)) -> (aext (OP x, y)) |
| // fold (OP (trunc x), (trunc y)) -> (trunc (OP x, y)) (if trunc isn't free) |
| // |
| // do not sink logical op inside of a vector extend, since it may combine |
| // into a vsetcc. |
| EVT Op0VT = N0.getOperand(0).getValueType(); |
| if ((N0.getOpcode() == ISD::ZERO_EXTEND || |
| N0.getOpcode() == ISD::SIGN_EXTEND || |
| // Avoid infinite looping with PromoteIntBinOp. |
| (N0.getOpcode() == ISD::ANY_EXTEND && |
| (!LegalTypes || TLI.isTypeDesirableForOp(N->getOpcode(), Op0VT))) || |
| (N0.getOpcode() == ISD::TRUNCATE && |
| (!TLI.isZExtFree(VT, Op0VT) || |
| !TLI.isTruncateFree(Op0VT, VT)) && |
| TLI.isTypeLegal(Op0VT))) && |
| !VT.isVector() && |
| Op0VT == N1.getOperand(0).getValueType() && |
| (!LegalOperations || TLI.isOperationLegal(N->getOpcode(), Op0VT))) { |
| SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(), |
| N0.getOperand(0).getValueType(), |
| N0.getOperand(0), N1.getOperand(0)); |
| AddToWorkList(ORNode.getNode()); |
| return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, ORNode); |
| } |
| |
| // For each of OP in SHL/SRL/SRA/AND... |
| // fold (and (OP x, z), (OP y, z)) -> (OP (and x, y), z) |
| // fold (or (OP x, z), (OP y, z)) -> (OP (or x, y), z) |
| // fold (xor (OP x, z), (OP y, z)) -> (OP (xor x, y), z) |
| if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL || |
| N0.getOpcode() == ISD::SRA || N0.getOpcode() == ISD::AND) && |
| N0.getOperand(1) == N1.getOperand(1)) { |
| SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(), |
| N0.getOperand(0).getValueType(), |
| N0.getOperand(0), N1.getOperand(0)); |
| AddToWorkList(ORNode.getNode()); |
| return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, |
| ORNode, N0.getOperand(1)); |
| } |
| |
| // Simplify xor/and/or (bitcast(A), bitcast(B)) -> bitcast(op (A,B)) |
| // Only perform this optimization after type legalization and before |
| // LegalizeVectorOprs. LegalizeVectorOprs promotes vector operations by |
| // adding bitcasts. For example (xor v4i32) is promoted to (v2i64), and |
| // we don't want to undo this promotion. |
| // We also handle SCALAR_TO_VECTOR because xor/or/and operations are cheaper |
| // on scalars. |
| if ((N0.getOpcode() == ISD::BITCAST || |
| N0.getOpcode() == ISD::SCALAR_TO_VECTOR) && |
| Level == AfterLegalizeTypes) { |
| SDValue In0 = N0.getOperand(0); |
| SDValue In1 = N1.getOperand(0); |
| EVT In0Ty = In0.getValueType(); |
| EVT In1Ty = In1.getValueType(); |
| DebugLoc DL = N->getDebugLoc(); |
| // If both incoming values are integers, and the original types are the |
| // same. |
| if (In0Ty.isInteger() && In1Ty.isInteger() && In0Ty == In1Ty) { |
| SDValue Op = DAG.getNode(N->getOpcode(), DL, In0Ty, In0, In1); |
| SDValue BC = DAG.getNode(N0.getOpcode(), DL, VT, Op); |
| AddToWorkList(Op.getNode()); |
| return BC; |
| } |
| } |
| |
| // Xor/and/or are indifferent to the swizzle operation (shuffle of one value). |
| // Simplify xor/and/or (shuff(A), shuff(B)) -> shuff(op (A,B)) |
| // If both shuffles use the same mask, and both shuffle within a single |
| // vector, then it is worthwhile to move the swizzle after the operation. |
| // The type-legalizer generates this pattern when loading illegal |
| // vector types from memory. In many cases this allows additional shuffle |
| // optimizations. |
| if (N0.getOpcode() == ISD::VECTOR_SHUFFLE && Level < AfterLegalizeDAG && |
| N0.getOperand(1).getOpcode() == ISD::UNDEF && |
| N1.getOperand(1).getOpcode() == ISD::UNDEF) { |
| ShuffleVectorSDNode *SVN0 = cast<ShuffleVectorSDNode>(N0); |
| ShuffleVectorSDNode *SVN1 = cast<ShuffleVectorSDNode>(N1); |
| |
| assert(N0.getOperand(0).getValueType() == N1.getOperand(1).getValueType() && |
| "Inputs to shuffles are not the same type"); |
| |
| unsigned NumElts = VT.getVectorNumElements(); |
| |
| // Check that both shuffles use the same mask. The masks are known to be of |
| // the same length because the result vector type is the same. |
| bool SameMask = true; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| int Idx0 = SVN0->getMaskElt(i); |
| int Idx1 = SVN1->getMaskElt(i); |
| if (Idx0 != Idx1) { |
| SameMask = false; |
| break; |
| } |
| } |
| |
| if (SameMask) { |
| SDValue Op = DAG.getNode(N->getOpcode(), N->getDebugLoc(), VT, |
| N0.getOperand(0), N1.getOperand(0)); |
| AddToWorkList(Op.getNode()); |
| return DAG.getVectorShuffle(VT, N->getDebugLoc(), Op, |
| DAG.getUNDEF(VT), &SVN0->getMask()[0]); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitAND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue LL, LR, RL, RR, CC0, CC1; |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N1.getValueType(); |
| unsigned BitWidth = VT.getScalarType().getSizeInBits(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| |
| // fold (and x, 0) -> 0, vector edition |
| if (ISD::isBuildVectorAllZeros(N0.getNode())) |
| return N0; |
| if (ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N1; |
| |
| // fold (and x, -1) -> x, vector edition |
| if (ISD::isBuildVectorAllOnes(N0.getNode())) |
| return N1; |
| if (ISD::isBuildVectorAllOnes(N1.getNode())) |
| return N0; |
| } |
| |
| // fold (and x, undef) -> 0 |
| if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // fold (and c1, c2) -> c1&c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::AND, VT, N0C, N1C); |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N1, N0); |
| // fold (and x, -1) -> x |
| if (N1C && N1C->isAllOnesValue()) |
| return N0; |
| // if (and x, c) is known to be zero, return 0 |
| if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0), |
| APInt::getAllOnesValue(BitWidth))) |
| return DAG.getConstant(0, VT); |
| // reassociate and |
| SDValue RAND = ReassociateOps(ISD::AND, N->getDebugLoc(), N0, N1); |
| if (RAND.getNode() != 0) |
| return RAND; |
| // fold (and (or x, C), D) -> D if (C & D) == D |
| if (N1C && N0.getOpcode() == ISD::OR) |
| if (ConstantSDNode *ORI = dyn_cast<ConstantSDNode>(N0.getOperand(1))) |
| if ((ORI->getAPIntValue() & N1C->getAPIntValue()) == N1C->getAPIntValue()) |
| return N1; |
| // fold (and (any_ext V), c) -> (zero_ext V) if 'and' only clears top bits. |
| if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) { |
| SDValue N0Op0 = N0.getOperand(0); |
| APInt Mask = ~N1C->getAPIntValue(); |
| Mask = Mask.trunc(N0Op0.getValueSizeInBits()); |
| if (DAG.MaskedValueIsZero(N0Op0, Mask)) { |
| SDValue Zext = DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), |
| N0.getValueType(), N0Op0); |
| |
| // Replace uses of the AND with uses of the Zero extend node. |
| CombineTo(N, Zext); |
| |
| // We actually want to replace all uses of the any_extend with the |
| // zero_extend, to avoid duplicating things. This will later cause this |
| // AND to be folded. |
| CombineTo(N0.getNode(), Zext); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| // similarly fold (and (X (load ([non_ext|any_ext|zero_ext] V))), c) -> |
| // (X (load ([non_ext|zero_ext] V))) if 'and' only clears top bits which must |
| // already be zero by virtue of the width of the base type of the load. |
| // |
| // the 'X' node here can either be nothing or an extract_vector_elt to catch |
| // more cases. |
| if ((N0.getOpcode() == ISD::EXTRACT_VECTOR_ELT && |
| N0.getOperand(0).getOpcode() == ISD::LOAD) || |
| N0.getOpcode() == ISD::LOAD) { |
| LoadSDNode *Load = cast<LoadSDNode>( (N0.getOpcode() == ISD::LOAD) ? |
| N0 : N0.getOperand(0) ); |
| |
| // Get the constant (if applicable) the zero'th operand is being ANDed with. |
| // This can be a pure constant or a vector splat, in which case we treat the |
| // vector as a scalar and use the splat value. |
| APInt Constant = APInt::getNullValue(1); |
| if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(N1)) { |
| Constant = C->getAPIntValue(); |
| } else if (BuildVectorSDNode *Vector = dyn_cast<BuildVectorSDNode>(N1)) { |
| APInt SplatValue, SplatUndef; |
| unsigned SplatBitSize; |
| bool HasAnyUndefs; |
| bool IsSplat = Vector->isConstantSplat(SplatValue, SplatUndef, |
| SplatBitSize, HasAnyUndefs); |
| if (IsSplat) { |
| // Undef bits can contribute to a possible optimisation if set, so |
| // set them. |
| SplatValue |= SplatUndef; |
| |
| // The splat value may be something like "0x00FFFFFF", which means 0 for |
| // the first vector value and FF for the rest, repeating. We need a mask |
| // that will apply equally to all members of the vector, so AND all the |
| // lanes of the constant together. |
| EVT VT = Vector->getValueType(0); |
| unsigned BitWidth = VT.getVectorElementType().getSizeInBits(); |
| |
| // If the splat value has been compressed to a bitlength lower |
| // than the size of the vector lane, we need to re-expand it to |
| // the lane size. |
| if (BitWidth > SplatBitSize) |
| for (SplatValue = SplatValue.zextOrTrunc(BitWidth); |
| SplatBitSize < BitWidth; |
| SplatBitSize = SplatBitSize * 2) |
| SplatValue |= SplatValue.shl(SplatBitSize); |
| |
| Constant = APInt::getAllOnesValue(BitWidth); |
| for (unsigned i = 0, n = SplatBitSize/BitWidth; i < n; ++i) |
| Constant &= SplatValue.lshr(i*BitWidth).zextOrTrunc(BitWidth); |
| } |
| } |
| |
| // If we want to change an EXTLOAD to a ZEXTLOAD, ensure a ZEXTLOAD is |
| // actually legal and isn't going to get expanded, else this is a false |
| // optimisation. |
| bool CanZextLoadProfitably = TLI.isLoadExtLegal(ISD::ZEXTLOAD, |
| Load->getMemoryVT()); |
| |
| // Resize the constant to the same size as the original memory access before |
| // extension. If it is still the AllOnesValue then this AND is completely |
| // unneeded. |
| Constant = |
| Constant.zextOrTrunc(Load->getMemoryVT().getScalarType().getSizeInBits()); |
| |
| bool B; |
| switch (Load->getExtensionType()) { |
| default: B = false; break; |
| case ISD::EXTLOAD: B = CanZextLoadProfitably; break; |
| case ISD::ZEXTLOAD: |
| case ISD::NON_EXTLOAD: B = true; break; |
| } |
| |
| if (B && Constant.isAllOnesValue()) { |
| // If the load type was an EXTLOAD, convert to ZEXTLOAD in order to |
| // preserve semantics once we get rid of the AND. |
| SDValue NewLoad(Load, 0); |
| if (Load->getExtensionType() == ISD::EXTLOAD) { |
| NewLoad = DAG.getLoad(Load->getAddressingMode(), ISD::ZEXTLOAD, |
| Load->getValueType(0), Load->getDebugLoc(), |
| Load->getChain(), Load->getBasePtr(), |
| Load->getOffset(), Load->getMemoryVT(), |
| Load->getMemOperand()); |
| // Replace uses of the EXTLOAD with the new ZEXTLOAD. |
| if (Load->getNumValues() == 3) { |
| // PRE/POST_INC loads have 3 values. |
| SDValue To[] = { NewLoad.getValue(0), NewLoad.getValue(1), |
| NewLoad.getValue(2) }; |
| CombineTo(Load, To, 3, true); |
| } else { |
| CombineTo(Load, NewLoad.getValue(0), NewLoad.getValue(1)); |
| } |
| } |
| |
| // Fold the AND away, taking care not to fold to the old load node if we |
| // replaced it. |
| CombineTo(N, (N0.getNode() == Load) ? NewLoad : N0); |
| |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| // fold (and (setcc x), (setcc y)) -> (setcc (and x, y)) |
| if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){ |
| ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get(); |
| ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get(); |
| |
| if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 && |
| LL.getValueType().isInteger()) { |
| // fold (and (seteq X, 0), (seteq Y, 0)) -> (seteq (or X, Y), 0) |
| if (cast<ConstantSDNode>(LR)->isNullValue() && Op1 == ISD::SETEQ) { |
| SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(), |
| LR.getValueType(), LL, RL); |
| AddToWorkList(ORNode.getNode()); |
| return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1); |
| } |
| // fold (and (seteq X, -1), (seteq Y, -1)) -> (seteq (and X, Y), -1) |
| if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETEQ) { |
| SDValue ANDNode = DAG.getNode(ISD::AND, N0.getDebugLoc(), |
| LR.getValueType(), LL, RL); |
| AddToWorkList(ANDNode.getNode()); |
| return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1); |
| } |
| // fold (and (setgt X, -1), (setgt Y, -1)) -> (setgt (or X, Y), -1) |
| if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETGT) { |
| SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(), |
| LR.getValueType(), LL, RL); |
| AddToWorkList(ORNode.getNode()); |
| return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1); |
| } |
| } |
| // canonicalize equivalent to ll == rl |
| if (LL == RR && LR == RL) { |
| Op1 = ISD::getSetCCSwappedOperands(Op1); |
| std::swap(RL, RR); |
| } |
| if (LL == RL && LR == RR) { |
| bool isInteger = LL.getValueType().isInteger(); |
| ISD::CondCode Result = ISD::getSetCCAndOperation(Op0, Op1, isInteger); |
| if (Result != ISD::SETCC_INVALID && |
| (!LegalOperations || |
| (TLI.isCondCodeLegal(Result, LL.getSimpleValueType()) && |
| TLI.isOperationLegal(ISD::SETCC, |
| TLI.getSetCCResultType(N0.getSimpleValueType()))))) |
| return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(), |
| LL, LR, Result); |
| } |
| } |
| |
| // Simplify: (and (op x...), (op y...)) -> (op (and x, y)) |
| if (N0.getOpcode() == N1.getOpcode()) { |
| SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N); |
| if (Tmp.getNode()) return Tmp; |
| } |
| |
| // fold (and (sign_extend_inreg x, i16 to i32), 1) -> (and x, 1) |
| // fold (and (sra)) -> (and (srl)) when possible. |
| if (!VT.isVector() && |
| SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| // fold (zext_inreg (extload x)) -> (zextload x) |
| if (ISD::isEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode())) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| EVT MemVT = LN0->getMemoryVT(); |
| // If we zero all the possible extended bits, then we can turn this into |
| // a zextload if we are running before legalize or the operation is legal. |
| unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits(); |
| if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth, |
| BitWidth - MemVT.getScalarType().getSizeInBits())) && |
| ((!LegalOperations && !LN0->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT, |
| LN0->getChain(), LN0->getBasePtr(), |
| LN0->getPointerInfo(), MemVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| AddToWorkList(N); |
| CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| // fold (zext_inreg (sextload x)) -> (zextload x) iff load has one use |
| if (ISD::isSEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) && |
| N0.hasOneUse()) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| EVT MemVT = LN0->getMemoryVT(); |
| // If we zero all the possible extended bits, then we can turn this into |
| // a zextload if we are running before legalize or the operation is legal. |
| unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits(); |
| if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth, |
| BitWidth - MemVT.getScalarType().getSizeInBits())) && |
| ((!LegalOperations && !LN0->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| MemVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| AddToWorkList(N); |
| CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (and (load x), 255) -> (zextload x, i8) |
| // fold (and (extload x, i16), 255) -> (zextload x, i8) |
| // fold (and (any_ext (extload x, i16)), 255) -> (zextload x, i8) |
| if (N1C && (N0.getOpcode() == ISD::LOAD || |
| (N0.getOpcode() == ISD::ANY_EXTEND && |
| N0.getOperand(0).getOpcode() == ISD::LOAD))) { |
| bool HasAnyExt = N0.getOpcode() == ISD::ANY_EXTEND; |
| LoadSDNode *LN0 = HasAnyExt |
| ? cast<LoadSDNode>(N0.getOperand(0)) |
| : cast<LoadSDNode>(N0); |
| if (LN0->getExtensionType() != ISD::SEXTLOAD && |
| LN0->isUnindexed() && N0.hasOneUse() && LN0->hasOneUse()) { |
| uint32_t ActiveBits = N1C->getAPIntValue().getActiveBits(); |
| if (ActiveBits > 0 && APIntOps::isMask(ActiveBits, N1C->getAPIntValue())){ |
| EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), ActiveBits); |
| EVT LoadedVT = LN0->getMemoryVT(); |
| |
| if (ExtVT == LoadedVT && |
| (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) { |
| EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT; |
| |
| SDValue NewLoad = |
| DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy, |
| LN0->getChain(), LN0->getBasePtr(), |
| LN0->getPointerInfo(), |
| ExtVT, LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| AddToWorkList(N); |
| CombineTo(LN0, NewLoad, NewLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| // Do not change the width of a volatile load. |
| // Do not generate loads of non-round integer types since these can |
| // be expensive (and would be wrong if the type is not byte sized). |
| if (!LN0->isVolatile() && LoadedVT.bitsGT(ExtVT) && ExtVT.isRound() && |
| (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) { |
| EVT PtrType = LN0->getOperand(1).getValueType(); |
| |
| unsigned Alignment = LN0->getAlignment(); |
| SDValue NewPtr = LN0->getBasePtr(); |
| |
| // For big endian targets, we need to add an offset to the pointer |
| // to load the correct bytes. For little endian systems, we merely |
| // need to read fewer bytes from the same pointer. |
| if (TLI.isBigEndian()) { |
| unsigned LVTStoreBytes = LoadedVT.getStoreSize(); |
| unsigned EVTStoreBytes = ExtVT.getStoreSize(); |
| unsigned PtrOff = LVTStoreBytes - EVTStoreBytes; |
| NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(), PtrType, |
| NewPtr, DAG.getConstant(PtrOff, PtrType)); |
| Alignment = MinAlign(Alignment, PtrOff); |
| } |
| |
| AddToWorkList(NewPtr.getNode()); |
| |
| EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT; |
| SDValue Load = |
| DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy, |
| LN0->getChain(), NewPtr, |
| LN0->getPointerInfo(), |
| ExtVT, LN0->isVolatile(), LN0->isNonTemporal(), |
| Alignment); |
| AddToWorkList(N); |
| CombineTo(LN0, Load, Load.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| } |
| |
| if (N0.getOpcode() == ISD::ADD && N1.getOpcode() == ISD::SRL && |
| VT.getSizeInBits() <= 64) { |
| if (ConstantSDNode *ADDI = dyn_cast<ConstantSDNode>(N0.getOperand(1))) { |
| APInt ADDC = ADDI->getAPIntValue(); |
| if (!TLI.isLegalAddImmediate(ADDC.getSExtValue())) { |
| // Look for (and (add x, c1), (lshr y, c2)). If C1 wasn't a legal |
| // immediate for an add, but it is legal if its top c2 bits are set, |
| // transform the ADD so the immediate doesn't need to be materialized |
| // in a register. |
| if (ConstantSDNode *SRLI = dyn_cast<ConstantSDNode>(N1.getOperand(1))) { |
| APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(), |
| SRLI->getZExtValue()); |
| if (DAG.MaskedValueIsZero(N0.getOperand(1), Mask)) { |
| ADDC |= Mask; |
| if (TLI.isLegalAddImmediate(ADDC.getSExtValue())) { |
| SDValue NewAdd = |
| DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT, |
| N0.getOperand(0), DAG.getConstant(ADDC, VT)); |
| CombineTo(N0.getNode(), NewAdd); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| /// MatchBSwapHWord - Match (a >> 8) | (a << 8) as (bswap a) >> 16 |
| /// |
| SDValue DAGCombiner::MatchBSwapHWordLow(SDNode *N, SDValue N0, SDValue N1, |
| bool DemandHighBits) { |
| if (!LegalOperations) |
| return SDValue(); |
| |
| EVT VT = N->getValueType(0); |
| if (VT != MVT::i64 && VT != MVT::i32 && VT != MVT::i16) |
| return SDValue(); |
| if (!TLI.isOperationLegal(ISD::BSWAP, VT)) |
| return SDValue(); |
| |
| // Recognize (and (shl a, 8), 0xff), (and (srl a, 8), 0xff00) |
| bool LookPassAnd0 = false; |
| bool LookPassAnd1 = false; |
| if (N0.getOpcode() == ISD::AND && N0.getOperand(0).getOpcode() == ISD::SRL) |
| std::swap(N0, N1); |
| if (N1.getOpcode() == ISD::AND && N1.getOperand(0).getOpcode() == ISD::SHL) |
| std::swap(N0, N1); |
| if (N0.getOpcode() == ISD::AND) { |
| if (!N0.getNode()->hasOneUse()) |
| return SDValue(); |
| ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (!N01C || N01C->getZExtValue() != 0xFF00) |
| return SDValue(); |
| N0 = N0.getOperand(0); |
| LookPassAnd0 = true; |
| } |
| |
| if (N1.getOpcode() == ISD::AND) { |
| if (!N1.getNode()->hasOneUse()) |
| return SDValue(); |
| ConstantSDNode *N11C = dyn_cast<ConstantSDNode>(N1.getOperand(1)); |
| if (!N11C || N11C->getZExtValue() != 0xFF) |
| return SDValue(); |
| N1 = N1.getOperand(0); |
| LookPassAnd1 = true; |
| } |
| |
| if (N0.getOpcode() == ISD::SRL && N1.getOpcode() == ISD::SHL) |
| std::swap(N0, N1); |
| if (N0.getOpcode() != ISD::SHL || N1.getOpcode() != ISD::SRL) |
| return SDValue(); |
| if (!N0.getNode()->hasOneUse() || |
| !N1.getNode()->hasOneUse()) |
| return SDValue(); |
| |
| ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| ConstantSDNode *N11C = dyn_cast<ConstantSDNode>(N1.getOperand(1)); |
| if (!N01C || !N11C) |
| return SDValue(); |
| if (N01C->getZExtValue() != 8 || N11C->getZExtValue() != 8) |
| return SDValue(); |
| |
| // Look for (shl (and a, 0xff), 8), (srl (and a, 0xff00), 8) |
| SDValue N00 = N0->getOperand(0); |
| if (!LookPassAnd0 && N00.getOpcode() == ISD::AND) { |
| if (!N00.getNode()->hasOneUse()) |
| return SDValue(); |
| ConstantSDNode *N001C = dyn_cast<ConstantSDNode>(N00.getOperand(1)); |
| if (!N001C || N001C->getZExtValue() != 0xFF) |
| return SDValue(); |
| N00 = N00.getOperand(0); |
| LookPassAnd0 = true; |
| } |
| |
| SDValue N10 = N1->getOperand(0); |
| if (!LookPassAnd1 && N10.getOpcode() == ISD::AND) { |
| if (!N10.getNode()->hasOneUse()) |
| return SDValue(); |
| ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N10.getOperand(1)); |
| if (!N101C || N101C->getZExtValue() != 0xFF00) |
| return SDValue(); |
| N10 = N10.getOperand(0); |
| LookPassAnd1 = true; |
| } |
| |
| if (N00 != N10) |
| return SDValue(); |
| |
| // Make sure everything beyond the low halfword is zero since the SRL 16 |
| // will clear the top bits. |
| unsigned OpSizeInBits = VT.getSizeInBits(); |
| if (DemandHighBits && OpSizeInBits > 16 && |
| (!LookPassAnd0 || !LookPassAnd1) && |
| !DAG.MaskedValueIsZero(N10, APInt::getHighBitsSet(OpSizeInBits, 16))) |
| return SDValue(); |
| |
| SDValue Res = DAG.getNode(ISD::BSWAP, N->getDebugLoc(), VT, N00); |
| if (OpSizeInBits > 16) |
| Res = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, Res, |
| DAG.getConstant(OpSizeInBits-16, getShiftAmountTy(VT))); |
| return Res; |
| } |
| |
| /// isBSwapHWordElement - Return true if the specified node is an element |
| /// that makes up a 32-bit packed halfword byteswap. i.e. |
| /// ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0x00ff0000)<<8)|((x&0xff000000)>>8) |
| static bool isBSwapHWordElement(SDValue N, SmallVector<SDNode*,4> &Parts) { |
| if (!N.getNode()->hasOneUse()) |
| return false; |
| |
| unsigned Opc = N.getOpcode(); |
| if (Opc != ISD::AND && Opc != ISD::SHL && Opc != ISD::SRL) |
| return false; |
| |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N.getOperand(1)); |
| if (!N1C) |
| return false; |
| |
| unsigned Num; |
| switch (N1C->getZExtValue()) { |
| default: |
| return false; |
| case 0xFF: Num = 0; break; |
| case 0xFF00: Num = 1; break; |
| case 0xFF0000: Num = 2; break; |
| case 0xFF000000: Num = 3; break; |
| } |
| |
| // Look for (x & 0xff) << 8 as well as ((x << 8) & 0xff00). |
| SDValue N0 = N.getOperand(0); |
| if (Opc == ISD::AND) { |
| if (Num == 0 || Num == 2) { |
| // (x >> 8) & 0xff |
| // (x >> 8) & 0xff0000 |
| if (N0.getOpcode() != ISD::SRL) |
| return false; |
| ConstantSDNode *C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (!C || C->getZExtValue() != 8) |
| return false; |
| } else { |
| // (x << 8) & 0xff00 |
| // (x << 8) & 0xff000000 |
| if (N0.getOpcode() != ISD::SHL) |
| return false; |
| ConstantSDNode *C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (!C || C->getZExtValue() != 8) |
| return false; |
| } |
| } else if (Opc == ISD::SHL) { |
| // (x & 0xff) << 8 |
| // (x & 0xff0000) << 8 |
| if (Num != 0 && Num != 2) |
| return false; |
| ConstantSDNode *C = dyn_cast<ConstantSDNode>(N.getOperand(1)); |
| if (!C || C->getZExtValue() != 8) |
| return false; |
| } else { // Opc == ISD::SRL |
| // (x & 0xff00) >> 8 |
| // (x & 0xff000000) >> 8 |
| if (Num != 1 && Num != 3) |
| return false; |
| ConstantSDNode *C = dyn_cast<ConstantSDNode>(N.getOperand(1)); |
| if (!C || C->getZExtValue() != 8) |
| return false; |
| } |
| |
| if (Parts[Num]) |
| return false; |
| |
| Parts[Num] = N0.getOperand(0).getNode(); |
| return true; |
| } |
| |
| /// MatchBSwapHWord - Match a 32-bit packed halfword bswap. That is |
| /// ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0x00ff0000)<<8)|((x&0xff000000)>>8) |
| /// => (rotl (bswap x), 16) |
| SDValue DAGCombiner::MatchBSwapHWord(SDNode *N, SDValue N0, SDValue N1) { |
| if (!LegalOperations) |
| return SDValue(); |
| |
| EVT VT = N->getValueType(0); |
| if (VT != MVT::i32) |
| return SDValue(); |
| if (!TLI.isOperationLegal(ISD::BSWAP, VT)) |
| return SDValue(); |
| |
| SmallVector<SDNode*,4> Parts(4, (SDNode*)0); |
| // Look for either |
| // (or (or (and), (and)), (or (and), (and))) |
| // (or (or (or (and), (and)), (and)), (and)) |
| if (N0.getOpcode() != ISD::OR) |
| return SDValue(); |
| SDValue N00 = N0.getOperand(0); |
| SDValue N01 = N0.getOperand(1); |
| |
| if (N1.getOpcode() == ISD::OR && |
| N00.getNumOperands() == 2 && N01.getNumOperands() == 2) { |
| // (or (or (and), (and)), (or (and), (and))) |
| SDValue N000 = N00.getOperand(0); |
| if (!isBSwapHWordElement(N000, Parts)) |
| return SDValue(); |
| |
| SDValue N001 = N00.getOperand(1); |
| if (!isBSwapHWordElement(N001, Parts)) |
| return SDValue(); |
| SDValue N010 = N01.getOperand(0); |
| if (!isBSwapHWordElement(N010, Parts)) |
| return SDValue(); |
| SDValue N011 = N01.getOperand(1); |
| if (!isBSwapHWordElement(N011, Parts)) |
| return SDValue(); |
| } else { |
| // (or (or (or (and), (and)), (and)), (and)) |
| if (!isBSwapHWordElement(N1, Parts)) |
| return SDValue(); |
| if (!isBSwapHWordElement(N01, Parts)) |
| return SDValue(); |
| if (N00.getOpcode() != ISD::OR) |
| return SDValue(); |
| SDValue N000 = N00.getOperand(0); |
| if (!isBSwapHWordElement(N000, Parts)) |
| return SDValue(); |
| SDValue N001 = N00.getOperand(1); |
| if (!isBSwapHWordElement(N001, Parts)) |
| return SDValue(); |
| } |
| |
| // Make sure the parts are all coming from the same node. |
| if (Parts[0] != Parts[1] || Parts[0] != Parts[2] || Parts[0] != Parts[3]) |
| return SDValue(); |
| |
| SDValue BSwap = DAG.getNode(ISD::BSWAP, N->getDebugLoc(), VT, |
| SDValue(Parts[0],0)); |
| |
| // Result of the bswap should be rotated by 16. If it's not legal, than |
| // do (x << 16) | (x >> 16). |
| SDValue ShAmt = DAG.getConstant(16, getShiftAmountTy(VT)); |
| if (TLI.isOperationLegalOrCustom(ISD::ROTL, VT)) |
| return DAG.getNode(ISD::ROTL, N->getDebugLoc(), VT, BSwap, ShAmt); |
| if (TLI.isOperationLegalOrCustom(ISD::ROTR, VT)) |
| return DAG.getNode(ISD::ROTR, N->getDebugLoc(), VT, BSwap, ShAmt); |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, |
| DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, BSwap, ShAmt), |
| DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, BSwap, ShAmt)); |
| } |
| |
| SDValue DAGCombiner::visitOR(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue LL, LR, RL, RR, CC0, CC1; |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N1.getValueType(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| |
| // fold (or x, 0) -> x, vector edition |
| if (ISD::isBuildVectorAllZeros(N0.getNode())) |
| return N1; |
| if (ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N0; |
| |
| // fold (or x, -1) -> -1, vector edition |
| if (ISD::isBuildVectorAllOnes(N0.getNode())) |
| return N0; |
| if (ISD::isBuildVectorAllOnes(N1.getNode())) |
| return N1; |
| } |
| |
| // fold (or x, undef) -> -1 |
| if (!LegalOperations && |
| (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)) { |
| EVT EltVT = VT.isVector() ? VT.getVectorElementType() : VT; |
| return DAG.getConstant(APInt::getAllOnesValue(EltVT.getSizeInBits()), VT); |
| } |
| // fold (or c1, c2) -> c1|c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::OR, VT, N0C, N1C); |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N1, N0); |
| // fold (or x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // fold (or x, -1) -> -1 |
| if (N1C && N1C->isAllOnesValue()) |
| return N1; |
| // fold (or x, c) -> c iff (x & ~c) == 0 |
| if (N1C && DAG.MaskedValueIsZero(N0, ~N1C->getAPIntValue())) |
| return N1; |
| |
| // Recognize halfword bswaps as (bswap + rotl 16) or (bswap + shl 16) |
| SDValue BSwap = MatchBSwapHWord(N, N0, N1); |
| if (BSwap.getNode() != 0) |
| return BSwap; |
| BSwap = MatchBSwapHWordLow(N, N0, N1); |
| if (BSwap.getNode() != 0) |
| return BSwap; |
| |
| // reassociate or |
| SDValue ROR = ReassociateOps(ISD::OR, N->getDebugLoc(), N0, N1); |
| if (ROR.getNode() != 0) |
| return ROR; |
| // Canonicalize (or (and X, c1), c2) -> (and (or X, c2), c1|c2) |
| // iff (c1 & c2) == 0. |
| if (N1C && N0.getOpcode() == ISD::AND && N0.getNode()->hasOneUse() && |
| isa<ConstantSDNode>(N0.getOperand(1))) { |
| ConstantSDNode *C1 = cast<ConstantSDNode>(N0.getOperand(1)); |
| if ((C1->getAPIntValue() & N1C->getAPIntValue()) != 0) |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| DAG.getNode(ISD::OR, N0.getDebugLoc(), VT, |
| N0.getOperand(0), N1), |
| DAG.FoldConstantArithmetic(ISD::OR, VT, N1C, C1)); |
| } |
| // fold (or (setcc x), (setcc y)) -> (setcc (or x, y)) |
| if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){ |
| ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get(); |
| ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get(); |
| |
| if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 && |
| LL.getValueType().isInteger()) { |
| // fold (or (setne X, 0), (setne Y, 0)) -> (setne (or X, Y), 0) |
| // fold (or (setlt X, 0), (setlt Y, 0)) -> (setne (or X, Y), 0) |
| if (cast<ConstantSDNode>(LR)->isNullValue() && |
| (Op1 == ISD::SETNE || Op1 == ISD::SETLT)) { |
| SDValue ORNode = DAG.getNode(ISD::OR, LR.getDebugLoc(), |
| LR.getValueType(), LL, RL); |
| AddToWorkList(ORNode.getNode()); |
| return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1); |
| } |
| // fold (or (setne X, -1), (setne Y, -1)) -> (setne (and X, Y), -1) |
| // fold (or (setgt X, -1), (setgt Y -1)) -> (setgt (and X, Y), -1) |
| if (cast<ConstantSDNode>(LR)->isAllOnesValue() && |
| (Op1 == ISD::SETNE || Op1 == ISD::SETGT)) { |
| SDValue ANDNode = DAG.getNode(ISD::AND, LR.getDebugLoc(), |
| LR.getValueType(), LL, RL); |
| AddToWorkList(ANDNode.getNode()); |
| return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1); |
| } |
| } |
| // canonicalize equivalent to ll == rl |
| if (LL == RR && LR == RL) { |
| Op1 = ISD::getSetCCSwappedOperands(Op1); |
| std::swap(RL, RR); |
| } |
| if (LL == RL && LR == RR) { |
| bool isInteger = LL.getValueType().isInteger(); |
| ISD::CondCode Result = ISD::getSetCCOrOperation(Op0, Op1, isInteger); |
| if (Result != ISD::SETCC_INVALID && |
| (!LegalOperations || |
| (TLI.isCondCodeLegal(Result, LL.getSimpleValueType()) && |
| TLI.isOperationLegal(ISD::SETCC, |
| TLI.getSetCCResultType(N0.getValueType()))))) |
| return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(), |
| LL, LR, Result); |
| } |
| } |
| |
| // Simplify: (or (op x...), (op y...)) -> (op (or x, y)) |
| if (N0.getOpcode() == N1.getOpcode()) { |
| SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N); |
| if (Tmp.getNode()) return Tmp; |
| } |
| |
| // (or (and X, C1), (and Y, C2)) -> (and (or X, Y), C3) if possible. |
| if (N0.getOpcode() == ISD::AND && |
| N1.getOpcode() == ISD::AND && |
| N0.getOperand(1).getOpcode() == ISD::Constant && |
| N1.getOperand(1).getOpcode() == ISD::Constant && |
| // Don't increase # computations. |
| (N0.getNode()->hasOneUse() || N1.getNode()->hasOneUse())) { |
| // We can only do this xform if we know that bits from X that are set in C2 |
| // but not in C1 are already zero. Likewise for Y. |
| const APInt &LHSMask = |
| cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue(); |
| const APInt &RHSMask = |
| cast<ConstantSDNode>(N1.getOperand(1))->getAPIntValue(); |
| |
| if (DAG.MaskedValueIsZero(N0.getOperand(0), RHSMask&~LHSMask) && |
| DAG.MaskedValueIsZero(N1.getOperand(0), LHSMask&~RHSMask)) { |
| SDValue X = DAG.getNode(ISD::OR, N0.getDebugLoc(), VT, |
| N0.getOperand(0), N1.getOperand(0)); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, X, |
| DAG.getConstant(LHSMask | RHSMask, VT)); |
| } |
| } |
| |
| // See if this is some rotate idiom. |
| if (SDNode *Rot = MatchRotate(N0, N1, N->getDebugLoc())) |
| return SDValue(Rot, 0); |
| |
| // Simplify the operands using demanded-bits information. |
| if (!VT.isVector() && |
| SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| return SDValue(); |
| } |
| |
| /// MatchRotateHalf - Match "(X shl/srl V1) & V2" where V2 may not be present. |
| static bool MatchRotateHalf(SDValue Op, SDValue &Shift, SDValue &Mask) { |
| if (Op.getOpcode() == ISD::AND) { |
| if (isa<ConstantSDNode>(Op.getOperand(1))) { |
| Mask = Op.getOperand(1); |
| Op = Op.getOperand(0); |
| } else { |
| return false; |
| } |
| } |
| |
| if (Op.getOpcode() == ISD::SRL || Op.getOpcode() == ISD::SHL) { |
| Shift = Op; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| // MatchRotate - Handle an 'or' of two operands. If this is one of the many |
| // idioms for rotate, and if the target supports rotation instructions, generate |
| // a rot[lr]. |
| SDNode *DAGCombiner::MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL) { |
| // Must be a legal type. Expanded 'n promoted things won't work with rotates. |
| EVT VT = LHS.getValueType(); |
| if (!TLI.isTypeLegal(VT)) return 0; |
| |
| // The target must have at least one rotate flavor. |
| bool HasROTL = TLI.isOperationLegalOrCustom(ISD::ROTL, VT); |
| bool HasROTR = TLI.isOperationLegalOrCustom(ISD::ROTR, VT); |
| if (!HasROTL && !HasROTR) return 0; |
| |
| // Match "(X shl/srl V1) & V2" where V2 may not be present. |
| SDValue LHSShift; // The shift. |
| SDValue LHSMask; // AND value if any. |
| if (!MatchRotateHalf(LHS, LHSShift, LHSMask)) |
| return 0; // Not part of a rotate. |
| |
| SDValue RHSShift; // The shift. |
| SDValue RHSMask; // AND value if any. |
| if (!MatchRotateHalf(RHS, RHSShift, RHSMask)) |
| return 0; // Not part of a rotate. |
| |
| if (LHSShift.getOperand(0) != RHSShift.getOperand(0)) |
| return 0; // Not shifting the same value. |
| |
| if (LHSShift.getOpcode() == RHSShift.getOpcode()) |
| return 0; // Shifts must disagree. |
| |
| // Canonicalize shl to left side in a shl/srl pair. |
| if (RHSShift.getOpcode() == ISD::SHL) { |
| std::swap(LHS, RHS); |
| std::swap(LHSShift, RHSShift); |
| std::swap(LHSMask , RHSMask ); |
| } |
| |
| unsigned OpSizeInBits = VT.getSizeInBits(); |
| SDValue LHSShiftArg = LHSShift.getOperand(0); |
| SDValue LHSShiftAmt = LHSShift.getOperand(1); |
| SDValue RHSShiftAmt = RHSShift.getOperand(1); |
| |
| // fold (or (shl x, C1), (srl x, C2)) -> (rotl x, C1) |
| // fold (or (shl x, C1), (srl x, C2)) -> (rotr x, C2) |
| if (LHSShiftAmt.getOpcode() == ISD::Constant && |
| RHSShiftAmt.getOpcode() == ISD::Constant) { |
| uint64_t LShVal = cast<ConstantSDNode>(LHSShiftAmt)->getZExtValue(); |
| uint64_t RShVal = cast<ConstantSDNode>(RHSShiftAmt)->getZExtValue(); |
| if ((LShVal + RShVal) != OpSizeInBits) |
| return 0; |
| |
| SDValue Rot = DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT, |
| LHSShiftArg, HasROTL ? LHSShiftAmt : RHSShiftAmt); |
| |
| // If there is an AND of either shifted operand, apply it to the result. |
| if (LHSMask.getNode() || RHSMask.getNode()) { |
| APInt Mask = APInt::getAllOnesValue(OpSizeInBits); |
| |
| if (LHSMask.getNode()) { |
| APInt RHSBits = APInt::getLowBitsSet(OpSizeInBits, LShVal); |
| Mask &= cast<ConstantSDNode>(LHSMask)->getAPIntValue() | RHSBits; |
| } |
| if (RHSMask.getNode()) { |
| APInt LHSBits = APInt::getHighBitsSet(OpSizeInBits, RShVal); |
| Mask &= cast<ConstantSDNode>(RHSMask)->getAPIntValue() | LHSBits; |
| } |
| |
| Rot = DAG.getNode(ISD::AND, DL, VT, Rot, DAG.getConstant(Mask, VT)); |
| } |
| |
| return Rot.getNode(); |
| } |
| |
| // If there is a mask here, and we have a variable shift, we can't be sure |
| // that we're masking out the right stuff. |
| if (LHSMask.getNode() || RHSMask.getNode()) |
| return 0; |
| |
| // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotl x, y) |
| // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotr x, (sub 32, y)) |
| if (RHSShiftAmt.getOpcode() == ISD::SUB && |
| LHSShiftAmt == RHSShiftAmt.getOperand(1)) { |
| if (ConstantSDNode *SUBC = |
| dyn_cast<ConstantSDNode>(RHSShiftAmt.getOperand(0))) { |
| if (SUBC->getAPIntValue() == OpSizeInBits) { |
| return DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT, LHSShiftArg, |
| HasROTL ? LHSShiftAmt : RHSShiftAmt).getNode(); |
| } |
| } |
| } |
| |
| // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotr x, y) |
| // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotl x, (sub 32, y)) |
| if (LHSShiftAmt.getOpcode() == ISD::SUB && |
| RHSShiftAmt == LHSShiftAmt.getOperand(1)) { |
| if (ConstantSDNode *SUBC = |
| dyn_cast<ConstantSDNode>(LHSShiftAmt.getOperand(0))) { |
| if (SUBC->getAPIntValue() == OpSizeInBits) { |
| return DAG.getNode(HasROTR ? ISD::ROTR : ISD::ROTL, DL, VT, LHSShiftArg, |
| HasROTR ? RHSShiftAmt : LHSShiftAmt).getNode(); |
| } |
| } |
| } |
| |
| // Look for sign/zext/any-extended or truncate cases: |
| if ((LHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND || |
| LHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND || |
| LHSShiftAmt.getOpcode() == ISD::ANY_EXTEND || |
| LHSShiftAmt.getOpcode() == ISD::TRUNCATE) && |
| (RHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND || |
| RHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND || |
| RHSShiftAmt.getOpcode() == ISD::ANY_EXTEND || |
| RHSShiftAmt.getOpcode() == ISD::TRUNCATE)) { |
| SDValue LExtOp0 = LHSShiftAmt.getOperand(0); |
| SDValue RExtOp0 = RHSShiftAmt.getOperand(0); |
| if (RExtOp0.getOpcode() == ISD::SUB && |
| RExtOp0.getOperand(1) == LExtOp0) { |
| // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) -> |
| // (rotl x, y) |
| // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) -> |
| // (rotr x, (sub 32, y)) |
| if (ConstantSDNode *SUBC = |
| dyn_cast<ConstantSDNode>(RExtOp0.getOperand(0))) { |
| if (SUBC->getAPIntValue() == OpSizeInBits) { |
| return DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT, |
| LHSShiftArg, |
| HasROTL ? LHSShiftAmt : RHSShiftAmt).getNode(); |
| } |
| } |
| } else if (LExtOp0.getOpcode() == ISD::SUB && |
| RExtOp0 == LExtOp0.getOperand(1)) { |
| // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) -> |
| // (rotr x, y) |
| // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) -> |
| // (rotl x, (sub 32, y)) |
| if (ConstantSDNode *SUBC = |
| dyn_cast<ConstantSDNode>(LExtOp0.getOperand(0))) { |
| if (SUBC->getAPIntValue() == OpSizeInBits) { |
| return DAG.getNode(HasROTR ? ISD::ROTR : ISD::ROTL, DL, VT, |
| LHSShiftArg, |
| HasROTR ? RHSShiftAmt : LHSShiftAmt).getNode(); |
| } |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| SDValue DAGCombiner::visitXOR(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue LHS, RHS, CC; |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| |
| // fold (xor x, 0) -> x, vector edition |
| if (ISD::isBuildVectorAllZeros(N0.getNode())) |
| return N1; |
| if (ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N0; |
| } |
| |
| // fold (xor undef, undef) -> 0. This is a common idiom (misuse). |
| if (N0.getOpcode() == ISD::UNDEF && N1.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // fold (xor x, undef) -> undef |
| if (N0.getOpcode() == ISD::UNDEF) |
| return N0; |
| if (N1.getOpcode() == ISD::UNDEF) |
| return N1; |
| // fold (xor c1, c2) -> c1^c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::XOR, VT, N0C, N1C); |
| // canonicalize constant to RHS |
| if (N0C && !N1C) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0); |
| // fold (xor x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // reassociate xor |
| SDValue RXOR = ReassociateOps(ISD::XOR, N->getDebugLoc(), N0, N1); |
| if (RXOR.getNode() != 0) |
| return RXOR; |
| |
| // fold !(x cc y) -> (x !cc y) |
| if (N1C && N1C->getAPIntValue() == 1 && isSetCCEquivalent(N0, LHS, RHS, CC)) { |
| bool isInt = LHS.getValueType().isInteger(); |
| ISD::CondCode NotCC = ISD::getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), |
| isInt); |
| |
| if (!LegalOperations || |
| TLI.isCondCodeLegal(NotCC, LHS.getSimpleValueType())) { |
| switch (N0.getOpcode()) { |
| default: |
| llvm_unreachable("Unhandled SetCC Equivalent!"); |
| case ISD::SETCC: |
| return DAG.getSetCC(N->getDebugLoc(), VT, LHS, RHS, NotCC); |
| case ISD::SELECT_CC: |
| return DAG.getSelectCC(N->getDebugLoc(), LHS, RHS, N0.getOperand(2), |
| N0.getOperand(3), NotCC); |
| } |
| } |
| } |
| |
| // fold (not (zext (setcc x, y))) -> (zext (not (setcc x, y))) |
| if (N1C && N1C->getAPIntValue() == 1 && N0.getOpcode() == ISD::ZERO_EXTEND && |
| N0.getNode()->hasOneUse() && |
| isSetCCEquivalent(N0.getOperand(0), LHS, RHS, CC)){ |
| SDValue V = N0.getOperand(0); |
| V = DAG.getNode(ISD::XOR, N0.getDebugLoc(), V.getValueType(), V, |
| DAG.getConstant(1, V.getValueType())); |
| AddToWorkList(V.getNode()); |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, V); |
| } |
| |
| // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are setcc |
| if (N1C && N1C->getAPIntValue() == 1 && VT == MVT::i1 && |
| (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) { |
| SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1); |
| if (isOneUseSetCC(RHS) || isOneUseSetCC(LHS)) { |
| unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND; |
| LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS |
| RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS |
| AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode()); |
| return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS); |
| } |
| } |
| // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are constants |
| if (N1C && N1C->isAllOnesValue() && |
| (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) { |
| SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1); |
| if (isa<ConstantSDNode>(RHS) || isa<ConstantSDNode>(LHS)) { |
| unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND; |
| LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS |
| RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS |
| AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode()); |
| return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS); |
| } |
| } |
| // fold (xor (xor x, c1), c2) -> (xor x, (xor c1, c2)) |
| if (N1C && N0.getOpcode() == ISD::XOR) { |
| ConstantSDNode *N00C = dyn_cast<ConstantSDNode>(N0.getOperand(0)); |
| ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (N00C) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(1), |
| DAG.getConstant(N1C->getAPIntValue() ^ |
| N00C->getAPIntValue(), VT)); |
| if (N01C) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(N1C->getAPIntValue() ^ |
| N01C->getAPIntValue(), VT)); |
| } |
| // fold (xor x, x) -> 0 |
| if (N0 == N1) |
| return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations); |
| |
| // Simplify: xor (op x...), (op y...) -> (op (xor x, y)) |
| if (N0.getOpcode() == N1.getOpcode()) { |
| SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N); |
| if (Tmp.getNode()) return Tmp; |
| } |
| |
| // Simplify the expression using non-local knowledge. |
| if (!VT.isVector() && |
| SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| return SDValue(); |
| } |
| |
| /// visitShiftByConstant - Handle transforms common to the three shifts, when |
| /// the shift amount is a constant. |
| SDValue DAGCombiner::visitShiftByConstant(SDNode *N, unsigned Amt) { |
| SDNode *LHS = N->getOperand(0).getNode(); |
| if (!LHS->hasOneUse()) return SDValue(); |
| |
| // We want to pull some binops through shifts, so that we have (and (shift)) |
| // instead of (shift (and)), likewise for add, or, xor, etc. This sort of |
| // thing happens with address calculations, so it's important to canonicalize |
| // it. |
| bool HighBitSet = false; // Can we transform this if the high bit is set? |
| |
| switch (LHS->getOpcode()) { |
| default: return SDValue(); |
| case ISD::OR: |
| case ISD::XOR: |
| HighBitSet = false; // We can only transform sra if the high bit is clear. |
| break; |
| case ISD::AND: |
| HighBitSet = true; // We can only transform sra if the high bit is set. |
| break; |
| case ISD::ADD: |
| if (N->getOpcode() != ISD::SHL) |
| return SDValue(); // only shl(add) not sr[al](add). |
| HighBitSet = false; // We can only transform sra if the high bit is clear. |
| break; |
| } |
| |
| // We require the RHS of the binop to be a constant as well. |
| ConstantSDNode *BinOpCst = dyn_cast<ConstantSDNode>(LHS->getOperand(1)); |
| if (!BinOpCst) return SDValue(); |
| |
| // FIXME: disable this unless the input to the binop is a shift by a constant. |
| // If it is not a shift, it pessimizes some common cases like: |
| // |
| // void foo(int *X, int i) { X[i & 1235] = 1; } |
| // int bar(int *X, int i) { return X[i & 255]; } |
| SDNode *BinOpLHSVal = LHS->getOperand(0).getNode(); |
| if ((BinOpLHSVal->getOpcode() != ISD::SHL && |
| BinOpLHSVal->getOpcode() != ISD::SRA && |
| BinOpLHSVal->getOpcode() != ISD::SRL) || |
| !isa<ConstantSDNode>(BinOpLHSVal->getOperand(1))) |
| return SDValue(); |
| |
| EVT VT = N->getValueType(0); |
| |
| // If this is a signed shift right, and the high bit is modified by the |
| // logical operation, do not perform the transformation. The highBitSet |
| // boolean indicates the value of the high bit of the constant which would |
| // cause it to be modified for this operation. |
| if (N->getOpcode() == ISD::SRA) { |
| bool BinOpRHSSignSet = BinOpCst->getAPIntValue().isNegative(); |
| if (BinOpRHSSignSet != HighBitSet) |
| return SDValue(); |
| } |
| |
| // Fold the constants, shifting the binop RHS by the shift amount. |
| SDValue NewRHS = DAG.getNode(N->getOpcode(), LHS->getOperand(1).getDebugLoc(), |
| N->getValueType(0), |
| LHS->getOperand(1), N->getOperand(1)); |
| |
| // Create the new shift. |
| SDValue NewShift = DAG.getNode(N->getOpcode(), |
| LHS->getOperand(0).getDebugLoc(), |
| VT, LHS->getOperand(0), N->getOperand(1)); |
| |
| // Create the new binop. |
| return DAG.getNode(LHS->getOpcode(), N->getDebugLoc(), VT, NewShift, NewRHS); |
| } |
| |
| SDValue DAGCombiner::visitSHL(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| unsigned OpSizeInBits = VT.getScalarType().getSizeInBits(); |
| |
| // fold (shl c1, c2) -> c1<<c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::SHL, VT, N0C, N1C); |
| // fold (shl 0, x) -> 0 |
| if (N0C && N0C->isNullValue()) |
| return N0; |
| // fold (shl x, c >= size(x)) -> undef |
| if (N1C && N1C->getZExtValue() >= OpSizeInBits) |
| return DAG.getUNDEF(VT); |
| // fold (shl x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // fold (shl undef, x) -> 0 |
| if (N0.getOpcode() == ISD::UNDEF) |
| return DAG.getConstant(0, VT); |
| // if (shl x, c) is known to be zero, return 0 |
| if (DAG.MaskedValueIsZero(SDValue(N, 0), |
| APInt::getAllOnesValue(OpSizeInBits))) |
| return DAG.getConstant(0, VT); |
| // fold (shl x, (trunc (and y, c))) -> (shl x, (and (trunc y), (trunc c))). |
| if (N1.getOpcode() == ISD::TRUNCATE && |
| N1.getOperand(0).getOpcode() == ISD::AND && |
| N1.hasOneUse() && N1.getOperand(0).hasOneUse()) { |
| SDValue N101 = N1.getOperand(0).getOperand(1); |
| if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) { |
| EVT TruncVT = N1.getValueType(); |
| SDValue N100 = N1.getOperand(0).getOperand(0); |
| APInt TruncC = N101C->getAPIntValue(); |
| TruncC = TruncC.trunc(TruncVT.getSizeInBits()); |
| return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0, |
| DAG.getNode(ISD::AND, N->getDebugLoc(), TruncVT, |
| DAG.getNode(ISD::TRUNCATE, |
| N->getDebugLoc(), |
| TruncVT, N100), |
| DAG.getConstant(TruncC, TruncVT))); |
| } |
| } |
| |
| if (N1C && SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| // fold (shl (shl x, c1), c2) -> 0 or (shl x, (add c1, c2)) |
| if (N1C && N0.getOpcode() == ISD::SHL && |
| N0.getOperand(1).getOpcode() == ISD::Constant) { |
| uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue(); |
| uint64_t c2 = N1C->getZExtValue(); |
| if (c1 + c2 >= OpSizeInBits) |
| return DAG.getConstant(0, VT); |
| return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(c1 + c2, N1.getValueType())); |
| } |
| |
| // fold (shl (ext (shl x, c1)), c2) -> (ext (shl x, (add c1, c2))) |
| // For this to be valid, the second form must not preserve any of the bits |
| // that are shifted out by the inner shift in the first form. This means |
| // the outer shift size must be >= the number of bits added by the ext. |
| // As a corollary, we don't care what kind of ext it is. |
| if (N1C && (N0.getOpcode() == ISD::ZERO_EXTEND || |
| N0.getOpcode() == ISD::ANY_EXTEND || |
| N0.getOpcode() == ISD::SIGN_EXTEND) && |
| N0.getOperand(0).getOpcode() == ISD::SHL && |
| isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) { |
| uint64_t c1 = |
| cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue(); |
| uint64_t c2 = N1C->getZExtValue(); |
| EVT InnerShiftVT = N0.getOperand(0).getValueType(); |
| uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits(); |
| if (c2 >= OpSizeInBits - InnerShiftSize) { |
| if (c1 + c2 >= OpSizeInBits) |
| return DAG.getConstant(0, VT); |
| return DAG.getNode(ISD::SHL, N0->getDebugLoc(), VT, |
| DAG.getNode(N0.getOpcode(), N0->getDebugLoc(), VT, |
| N0.getOperand(0)->getOperand(0)), |
| DAG.getConstant(c1 + c2, N1.getValueType())); |
| } |
| } |
| |
| // fold (shl (srl x, c1), c2) -> (and (shl x, (sub c2, c1), MASK) or |
| // (and (srl x, (sub c1, c2), MASK) |
| // Only fold this if the inner shift has no other uses -- if it does, folding |
| // this will increase the total number of instructions. |
| if (N1C && N0.getOpcode() == ISD::SRL && N0.hasOneUse() && |
| N0.getOperand(1).getOpcode() == ISD::Constant) { |
| uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue(); |
| if (c1 < VT.getSizeInBits()) { |
| uint64_t c2 = N1C->getZExtValue(); |
| APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(), |
| VT.getSizeInBits() - c1); |
| SDValue Shift; |
| if (c2 > c1) { |
| Mask = Mask.shl(c2-c1); |
| Shift = DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(c2-c1, N1.getValueType())); |
| } else { |
| Mask = Mask.lshr(c1-c2); |
| Shift = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(c1-c2, N1.getValueType())); |
| } |
| return DAG.getNode(ISD::AND, N0.getDebugLoc(), VT, Shift, |
| DAG.getConstant(Mask, VT)); |
| } |
| } |
| // fold (shl (sra x, c1), c1) -> (and x, (shl -1, c1)) |
| if (N1C && N0.getOpcode() == ISD::SRA && N1 == N0.getOperand(1)) { |
| SDValue HiBitsMask = |
| DAG.getConstant(APInt::getHighBitsSet(VT.getSizeInBits(), |
| VT.getSizeInBits() - |
| N1C->getZExtValue()), |
| VT); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0), |
| HiBitsMask); |
| } |
| |
| if (N1C) { |
| SDValue NewSHL = visitShiftByConstant(N, N1C->getZExtValue()); |
| if (NewSHL.getNode()) |
| return NewSHL; |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSRA(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| unsigned OpSizeInBits = VT.getScalarType().getSizeInBits(); |
| |
| // fold (sra c1, c2) -> (sra c1, c2) |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::SRA, VT, N0C, N1C); |
| // fold (sra 0, x) -> 0 |
| if (N0C && N0C->isNullValue()) |
| return N0; |
| // fold (sra -1, x) -> -1 |
| if (N0C && N0C->isAllOnesValue()) |
| return N0; |
| // fold (sra x, (setge c, size(x))) -> undef |
| if (N1C && N1C->getZExtValue() >= OpSizeInBits) |
| return DAG.getUNDEF(VT); |
| // fold (sra x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // fold (sra (shl x, c1), c1) -> sext_inreg for some c1 and target supports |
| // sext_inreg. |
| if (N1C && N0.getOpcode() == ISD::SHL && N1 == N0.getOperand(1)) { |
| unsigned LowBits = OpSizeInBits - (unsigned)N1C->getZExtValue(); |
| EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), LowBits); |
| if (VT.isVector()) |
| ExtVT = EVT::getVectorVT(*DAG.getContext(), |
| ExtVT, VT.getVectorNumElements()); |
| if ((!LegalOperations || |
| TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, ExtVT))) |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, |
| N0.getOperand(0), DAG.getValueType(ExtVT)); |
| } |
| |
| // fold (sra (sra x, c1), c2) -> (sra x, (add c1, c2)) |
| if (N1C && N0.getOpcode() == ISD::SRA) { |
| if (ConstantSDNode *C1 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) { |
| unsigned Sum = N1C->getZExtValue() + C1->getZExtValue(); |
| if (Sum >= OpSizeInBits) Sum = OpSizeInBits-1; |
| return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(Sum, N1C->getValueType(0))); |
| } |
| } |
| |
| // fold (sra (shl X, m), (sub result_size, n)) |
| // -> (sign_extend (trunc (shl X, (sub (sub result_size, n), m)))) for |
| // result_size - n != m. |
| // If truncate is free for the target sext(shl) is likely to result in better |
| // code. |
| if (N0.getOpcode() == ISD::SHL) { |
| // Get the two constanst of the shifts, CN0 = m, CN = n. |
| const ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (N01C && N1C) { |
| // Determine what the truncate's result bitsize and type would be. |
| EVT TruncVT = |
| EVT::getIntegerVT(*DAG.getContext(), |
| OpSizeInBits - N1C->getZExtValue()); |
| // Determine the residual right-shift amount. |
| signed ShiftAmt = N1C->getZExtValue() - N01C->getZExtValue(); |
| |
| // If the shift is not a no-op (in which case this should be just a sign |
| // extend already), the truncated to type is legal, sign_extend is legal |
| // on that type, and the truncate to that type is both legal and free, |
| // perform the transform. |
| if ((ShiftAmt > 0) && |
| TLI.isOperationLegalOrCustom(ISD::SIGN_EXTEND, TruncVT) && |
| TLI.isOperationLegalOrCustom(ISD::TRUNCATE, VT) && |
| TLI.isTruncateFree(VT, TruncVT)) { |
| |
| SDValue Amt = DAG.getConstant(ShiftAmt, |
| getShiftAmountTy(N0.getOperand(0).getValueType())); |
| SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT, |
| N0.getOperand(0), Amt); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), TruncVT, |
| Shift); |
| return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), |
| N->getValueType(0), Trunc); |
| } |
| } |
| } |
| |
| // fold (sra x, (trunc (and y, c))) -> (sra x, (and (trunc y), (trunc c))). |
| if (N1.getOpcode() == ISD::TRUNCATE && |
| N1.getOperand(0).getOpcode() == ISD::AND && |
| N1.hasOneUse() && N1.getOperand(0).hasOneUse()) { |
| SDValue N101 = N1.getOperand(0).getOperand(1); |
| if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) { |
| EVT TruncVT = N1.getValueType(); |
| SDValue N100 = N1.getOperand(0).getOperand(0); |
| APInt TruncC = N101C->getAPIntValue(); |
| TruncC = TruncC.trunc(TruncVT.getScalarType().getSizeInBits()); |
| return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0, |
| DAG.getNode(ISD::AND, N->getDebugLoc(), |
| TruncVT, |
| DAG.getNode(ISD::TRUNCATE, |
| N->getDebugLoc(), |
| TruncVT, N100), |
| DAG.getConstant(TruncC, TruncVT))); |
| } |
| } |
| |
| // fold (sra (trunc (sr x, c1)), c2) -> (trunc (sra x, c1+c2)) |
| // if c1 is equal to the number of bits the trunc removes |
| if (N0.getOpcode() == ISD::TRUNCATE && |
| (N0.getOperand(0).getOpcode() == ISD::SRL || |
| N0.getOperand(0).getOpcode() == ISD::SRA) && |
| N0.getOperand(0).hasOneUse() && |
| N0.getOperand(0).getOperand(1).hasOneUse() && |
| N1C && isa<ConstantSDNode>(N0.getOperand(0).getOperand(1))) { |
| EVT LargeVT = N0.getOperand(0).getValueType(); |
| ConstantSDNode *LargeShiftAmt = |
| cast<ConstantSDNode>(N0.getOperand(0).getOperand(1)); |
| |
| if (LargeVT.getScalarType().getSizeInBits() - OpSizeInBits == |
| LargeShiftAmt->getZExtValue()) { |
| SDValue Amt = |
| DAG.getConstant(LargeShiftAmt->getZExtValue() + N1C->getZExtValue(), |
| getShiftAmountTy(N0.getOperand(0).getOperand(0).getValueType())); |
| SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), LargeVT, |
| N0.getOperand(0).getOperand(0), Amt); |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, SRA); |
| } |
| } |
| |
| // Simplify, based on bits shifted out of the LHS. |
| if (N1C && SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| |
| // If the sign bit is known to be zero, switch this to a SRL. |
| if (DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, N1); |
| |
| if (N1C) { |
| SDValue NewSRA = visitShiftByConstant(N, N1C->getZExtValue()); |
| if (NewSRA.getNode()) |
| return NewSRA; |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSRL(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| EVT VT = N0.getValueType(); |
| unsigned OpSizeInBits = VT.getScalarType().getSizeInBits(); |
| |
| // fold (srl c1, c2) -> c1 >>u c2 |
| if (N0C && N1C) |
| return DAG.FoldConstantArithmetic(ISD::SRL, VT, N0C, N1C); |
| // fold (srl 0, x) -> 0 |
| if (N0C && N0C->isNullValue()) |
| return N0; |
| // fold (srl x, c >= size(x)) -> undef |
| if (N1C && N1C->getZExtValue() >= OpSizeInBits) |
| return DAG.getUNDEF(VT); |
| // fold (srl x, 0) -> x |
| if (N1C && N1C->isNullValue()) |
| return N0; |
| // if (srl x, c) is known to be zero, return 0 |
| if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0), |
| APInt::getAllOnesValue(OpSizeInBits))) |
| return DAG.getConstant(0, VT); |
| |
| // fold (srl (srl x, c1), c2) -> 0 or (srl x, (add c1, c2)) |
| if (N1C && N0.getOpcode() == ISD::SRL && |
| N0.getOperand(1).getOpcode() == ISD::Constant) { |
| uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue(); |
| uint64_t c2 = N1C->getZExtValue(); |
| if (c1 + c2 >= OpSizeInBits) |
| return DAG.getConstant(0, VT); |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(c1 + c2, N1.getValueType())); |
| } |
| |
| // fold (srl (trunc (srl x, c1)), c2) -> 0 or (trunc (srl x, (add c1, c2))) |
| if (N1C && N0.getOpcode() == ISD::TRUNCATE && |
| N0.getOperand(0).getOpcode() == ISD::SRL && |
| isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) { |
| uint64_t c1 = |
| cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue(); |
| uint64_t c2 = N1C->getZExtValue(); |
| EVT InnerShiftVT = N0.getOperand(0).getValueType(); |
| EVT ShiftCountVT = N0.getOperand(0)->getOperand(1).getValueType(); |
| uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits(); |
| // This is only valid if the OpSizeInBits + c1 = size of inner shift. |
| if (c1 + OpSizeInBits == InnerShiftSize) { |
| if (c1 + c2 >= InnerShiftSize) |
| return DAG.getConstant(0, VT); |
| return DAG.getNode(ISD::TRUNCATE, N0->getDebugLoc(), VT, |
| DAG.getNode(ISD::SRL, N0->getDebugLoc(), InnerShiftVT, |
| N0.getOperand(0)->getOperand(0), |
| DAG.getConstant(c1 + c2, ShiftCountVT))); |
| } |
| } |
| |
| // fold (srl (shl x, c), c) -> (and x, cst2) |
| if (N1C && N0.getOpcode() == ISD::SHL && N0.getOperand(1) == N1 && |
| N0.getValueSizeInBits() <= 64) { |
| uint64_t ShAmt = N1C->getZExtValue()+64-N0.getValueSizeInBits(); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getConstant(~0ULL >> ShAmt, VT)); |
| } |
| |
| |
| // fold (srl (anyextend x), c) -> (anyextend (srl x, c)) |
| if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) { |
| // Shifting in all undef bits? |
| EVT SmallVT = N0.getOperand(0).getValueType(); |
| if (N1C->getZExtValue() >= SmallVT.getSizeInBits()) |
| return DAG.getUNDEF(VT); |
| |
| if (!LegalTypes || TLI.isTypeDesirableForOp(ISD::SRL, SmallVT)) { |
| uint64_t ShiftAmt = N1C->getZExtValue(); |
| SDValue SmallShift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), SmallVT, |
| N0.getOperand(0), |
| DAG.getConstant(ShiftAmt, getShiftAmountTy(SmallVT))); |
| AddToWorkList(SmallShift.getNode()); |
| return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, SmallShift); |
| } |
| } |
| |
| // fold (srl (sra X, Y), 31) -> (srl X, 31). This srl only looks at the sign |
| // bit, which is unmodified by sra. |
| if (N1C && N1C->getZExtValue() + 1 == VT.getSizeInBits()) { |
| if (N0.getOpcode() == ISD::SRA) |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0), N1); |
| } |
| |
| // fold (srl (ctlz x), "5") -> x iff x has one bit set (the low bit). |
| if (N1C && N0.getOpcode() == ISD::CTLZ && |
| N1C->getAPIntValue() == Log2_32(VT.getSizeInBits())) { |
| APInt KnownZero, KnownOne; |
| DAG.ComputeMaskedBits(N0.getOperand(0), KnownZero, KnownOne); |
| |
| // If any of the input bits are KnownOne, then the input couldn't be all |
| // zeros, thus the result of the srl will always be zero. |
| if (KnownOne.getBoolValue()) return DAG.getConstant(0, VT); |
| |
| // If all of the bits input the to ctlz node are known to be zero, then |
| // the result of the ctlz is "32" and the result of the shift is one. |
| APInt UnknownBits = ~KnownZero; |
| if (UnknownBits == 0) return DAG.getConstant(1, VT); |
| |
| // Otherwise, check to see if there is exactly one bit input to the ctlz. |
| if ((UnknownBits & (UnknownBits - 1)) == 0) { |
| // Okay, we know that only that the single bit specified by UnknownBits |
| // could be set on input to the CTLZ node. If this bit is set, the SRL |
| // will return 0, if it is clear, it returns 1. Change the CTLZ/SRL pair |
| // to an SRL/XOR pair, which is likely to simplify more. |
| unsigned ShAmt = UnknownBits.countTrailingZeros(); |
| SDValue Op = N0.getOperand(0); |
| |
| if (ShAmt) { |
| Op = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT, Op, |
| DAG.getConstant(ShAmt, getShiftAmountTy(Op.getValueType()))); |
| AddToWorkList(Op.getNode()); |
| } |
| |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, |
| Op, DAG.getConstant(1, VT)); |
| } |
| } |
| |
| // fold (srl x, (trunc (and y, c))) -> (srl x, (and (trunc y), (trunc c))). |
| if (N1.getOpcode() == ISD::TRUNCATE && |
| N1.getOperand(0).getOpcode() == ISD::AND && |
| N1.hasOneUse() && N1.getOperand(0).hasOneUse()) { |
| SDValue N101 = N1.getOperand(0).getOperand(1); |
| if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) { |
| EVT TruncVT = N1.getValueType(); |
| SDValue N100 = N1.getOperand(0).getOperand(0); |
| APInt TruncC = N101C->getAPIntValue(); |
| TruncC = TruncC.trunc(TruncVT.getSizeInBits()); |
| return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, |
| DAG.getNode(ISD::AND, N->getDebugLoc(), |
| TruncVT, |
| DAG.getNode(ISD::TRUNCATE, |
| N->getDebugLoc(), |
| TruncVT, N100), |
| DAG.getConstant(TruncC, TruncVT))); |
| } |
| } |
| |
| // fold operands of srl based on knowledge that the low bits are not |
| // demanded. |
| if (N1C && SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| if (N1C) { |
| SDValue NewSRL = visitShiftByConstant(N, N1C->getZExtValue()); |
| if (NewSRL.getNode()) |
| return NewSRL; |
| } |
| |
| // Attempt to convert a srl of a load into a narrower zero-extending load. |
| SDValue NarrowLoad = ReduceLoadWidth(N); |
| if (NarrowLoad.getNode()) |
| return NarrowLoad; |
| |
| // Here is a common situation. We want to optimize: |
| // |
| // %a = ... |
| // %b = and i32 %a, 2 |
| // %c = srl i32 %b, 1 |
| // brcond i32 %c ... |
| // |
| // into |
| // |
| // %a = ... |
| // %b = and %a, 2 |
| // %c = setcc eq %b, 0 |
| // brcond %c ... |
| // |
| // However when after the source operand of SRL is optimized into AND, the SRL |
| // itself may not be optimized further. Look for it and add the BRCOND into |
| // the worklist. |
| if (N->hasOneUse()) { |
| SDNode *Use = *N->use_begin(); |
| if (Use->getOpcode() == ISD::BRCOND) |
| AddToWorkList(Use); |
| else if (Use->getOpcode() == ISD::TRUNCATE && Use->hasOneUse()) { |
| // Also look pass the truncate. |
| Use = *Use->use_begin(); |
| if (Use->getOpcode() == ISD::BRCOND) |
| AddToWorkList(Use); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCTLZ(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (ctlz c1) -> c2 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::CTLZ, N->getDebugLoc(), VT, N0); |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCTLZ_ZERO_UNDEF(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (ctlz_zero_undef c1) -> c2 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::CTLZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0); |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCTTZ(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (cttz c1) -> c2 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::CTTZ, N->getDebugLoc(), VT, N0); |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCTTZ_ZERO_UNDEF(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (cttz_zero_undef c1) -> c2 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::CTTZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0); |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCTPOP(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (ctpop c1) -> c2 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::CTPOP, N->getDebugLoc(), VT, N0); |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSELECT(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue N2 = N->getOperand(2); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1); |
| ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2); |
| EVT VT = N->getValueType(0); |
| EVT VT0 = N0.getValueType(); |
| |
| // fold (select C, X, X) -> X |
| if (N1 == N2) |
| return N1; |
| // fold (select true, X, Y) -> X |
| if (N0C && !N0C->isNullValue()) |
| return N1; |
| // fold (select false, X, Y) -> Y |
| if (N0C && N0C->isNullValue()) |
| return N2; |
| // fold (select C, 1, X) -> (or C, X) |
| if (VT == MVT::i1 && N1C && N1C->getAPIntValue() == 1) |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2); |
| // fold (select C, 0, 1) -> (xor C, 1) |
| if (VT.isInteger() && |
| (VT0 == MVT::i1 || |
| (VT0.isInteger() && |
| TLI.getBooleanContents(false) == |
| TargetLowering::ZeroOrOneBooleanContent)) && |
| N1C && N2C && N1C->isNullValue() && N2C->getAPIntValue() == 1) { |
| SDValue XORNode; |
| if (VT == VT0) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT0, |
| N0, DAG.getConstant(1, VT0)); |
| XORNode = DAG.getNode(ISD::XOR, N0.getDebugLoc(), VT0, |
| N0, DAG.getConstant(1, VT0)); |
| AddToWorkList(XORNode.getNode()); |
| if (VT.bitsGT(VT0)) |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, XORNode); |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, XORNode); |
| } |
| // fold (select C, 0, X) -> (and (not C), X) |
| if (VT == VT0 && VT == MVT::i1 && N1C && N1C->isNullValue()) { |
| SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT); |
| AddToWorkList(NOTNode.getNode()); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, NOTNode, N2); |
| } |
| // fold (select C, X, 1) -> (or (not C), X) |
| if (VT == VT0 && VT == MVT::i1 && N2C && N2C->getAPIntValue() == 1) { |
| SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT); |
| AddToWorkList(NOTNode.getNode()); |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, NOTNode, N1); |
| } |
| // fold (select C, X, 0) -> (and C, X) |
| if (VT == MVT::i1 && N2C && N2C->isNullValue()) |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1); |
| // fold (select X, X, Y) -> (or X, Y) |
| // fold (select X, 1, Y) -> (or X, Y) |
| if (VT == MVT::i1 && (N0 == N1 || (N1C && N1C->getAPIntValue() == 1))) |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2); |
| // fold (select X, Y, X) -> (and X, Y) |
| // fold (select X, Y, 0) -> (and X, Y) |
| if (VT == MVT::i1 && (N0 == N2 || (N2C && N2C->getAPIntValue() == 0))) |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1); |
| |
| // If we can fold this based on the true/false value, do so. |
| if (SimplifySelectOps(N, N1, N2)) |
| return SDValue(N, 0); // Don't revisit N. |
| |
| // fold selects based on a setcc into other things, such as min/max/abs |
| if (N0.getOpcode() == ISD::SETCC) { |
| // FIXME: |
| // Check against MVT::Other for SELECT_CC, which is a workaround for targets |
| // having to say they don't support SELECT_CC on every type the DAG knows |
| // about, since there is no way to mark an opcode illegal at all value types |
| if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other) && |
| TLI.isOperationLegalOrCustom(ISD::SELECT_CC, VT)) |
| return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1), |
| N1, N2, N0.getOperand(2)); |
| return SimplifySelect(N->getDebugLoc(), N0, N1, N2); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSELECT_CC(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue N2 = N->getOperand(2); |
| SDValue N3 = N->getOperand(3); |
| SDValue N4 = N->getOperand(4); |
| ISD::CondCode CC = cast<CondCodeSDNode>(N4)->get(); |
| |
| // fold select_cc lhs, rhs, x, x, cc -> x |
| if (N2 == N3) |
| return N2; |
| |
| // Determine if the condition we're dealing with is constant |
| SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()), |
| N0, N1, CC, N->getDebugLoc(), false); |
| if (SCC.getNode()) AddToWorkList(SCC.getNode()); |
| |
| if (ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode())) { |
| if (!SCCC->isNullValue()) |
| return N2; // cond always true -> true val |
| else |
| return N3; // cond always false -> false val |
| } |
| |
| // Fold to a simpler select_cc |
| if (SCC.getNode() && SCC.getOpcode() == ISD::SETCC) |
| return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), N2.getValueType(), |
| SCC.getOperand(0), SCC.getOperand(1), N2, N3, |
| SCC.getOperand(2)); |
| |
| // If we can fold this based on the true/false value, do so. |
| if (SimplifySelectOps(N, N2, N3)) |
| return SDValue(N, 0); // Don't revisit N. |
| |
| // fold select_cc into other things, such as min/max/abs |
| return SimplifySelectCC(N->getDebugLoc(), N0, N1, N2, N3, CC); |
| } |
| |
| SDValue DAGCombiner::visitSETCC(SDNode *N) { |
| return SimplifySetCC(N->getValueType(0), N->getOperand(0), N->getOperand(1), |
| cast<CondCodeSDNode>(N->getOperand(2))->get(), |
| N->getDebugLoc()); |
| } |
| |
| // ExtendUsesToFormExtLoad - Trying to extend uses of a load to enable this: |
| // "fold ({s|z|a}ext (load x)) -> ({s|z|a}ext (truncate ({s|z|a}extload x)))" |
| // transformation. Returns true if extension are possible and the above |
| // mentioned transformation is profitable. |
| static bool ExtendUsesToFormExtLoad(SDNode *N, SDValue N0, |
| unsigned ExtOpc, |
| SmallVector<SDNode*, 4> &ExtendNodes, |
| const TargetLowering &TLI) { |
| bool HasCopyToRegUses = false; |
| bool isTruncFree = TLI.isTruncateFree(N->getValueType(0), N0.getValueType()); |
| for (SDNode::use_iterator UI = N0.getNode()->use_begin(), |
| UE = N0.getNode()->use_end(); |
| UI != UE; ++UI) { |
| SDNode *User = *UI; |
| if (User == N) |
| continue; |
| if (UI.getUse().getResNo() != N0.getResNo()) |
| continue; |
| // FIXME: Only extend SETCC N, N and SETCC N, c for now. |
| if (ExtOpc != ISD::ANY_EXTEND && User->getOpcode() == ISD::SETCC) { |
| ISD::CondCode CC = cast<CondCodeSDNode>(User->getOperand(2))->get(); |
| if (ExtOpc == ISD::ZERO_EXTEND && ISD::isSignedIntSetCC(CC)) |
| // Sign bits will be lost after a zext. |
| return false; |
| bool Add = false; |
| for (unsigned i = 0; i != 2; ++i) { |
| SDValue UseOp = User->getOperand(i); |
| if (UseOp == N0) |
| continue; |
| if (!isa<ConstantSDNode>(UseOp)) |
| return false; |
| Add = true; |
| } |
| if (Add) |
| ExtendNodes.push_back(User); |
| continue; |
| } |
| // If truncates aren't free and there are users we can't |
| // extend, it isn't worthwhile. |
| if (!isTruncFree) |
| return false; |
| // Remember if this value is live-out. |
| if (User->getOpcode() == ISD::CopyToReg) |
| HasCopyToRegUses = true; |
| } |
| |
| if (HasCopyToRegUses) { |
| bool BothLiveOut = false; |
| for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end(); |
| UI != UE; ++UI) { |
| SDUse &Use = UI.getUse(); |
| if (Use.getResNo() == 0 && Use.getUser()->getOpcode() == ISD::CopyToReg) { |
| BothLiveOut = true; |
| break; |
| } |
| } |
| if (BothLiveOut) |
| // Both unextended and extended values are live out. There had better be |
| // a good reason for the transformation. |
| return ExtendNodes.size(); |
| } |
| return true; |
| } |
| |
| void DAGCombiner::ExtendSetCCUses(SmallVector<SDNode*, 4> SetCCs, |
| SDValue Trunc, SDValue ExtLoad, DebugLoc DL, |
| ISD::NodeType ExtType) { |
| // Extend SetCC uses if necessary. |
| for (unsigned i = 0, e = SetCCs.size(); i != e; ++i) { |
| SDNode *SetCC = SetCCs[i]; |
| SmallVector<SDValue, 4> Ops; |
| |
| for (unsigned j = 0; j != 2; ++j) { |
| SDValue SOp = SetCC->getOperand(j); |
| if (SOp == Trunc) |
| Ops.push_back(ExtLoad); |
| else |
| Ops.push_back(DAG.getNode(ExtType, DL, ExtLoad->getValueType(0), SOp)); |
| } |
| |
| Ops.push_back(SetCC->getOperand(2)); |
| CombineTo(SetCC, DAG.getNode(ISD::SETCC, DL, SetCC->getValueType(0), |
| &Ops[0], Ops.size())); |
| } |
| } |
| |
| SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (sext c1) -> c1 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N0); |
| |
| // fold (sext (sext x)) -> (sext x) |
| // fold (sext (aext x)) -> (sext x) |
| if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND) |
| return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, |
| N0.getOperand(0)); |
| |
| if (N0.getOpcode() == ISD::TRUNCATE) { |
| // fold (sext (truncate (load x))) -> (sext (smaller load x)) |
| // fold (sext (truncate (srl (load x), c))) -> (sext (smaller load (x+c/n))) |
| SDValue NarrowLoad = ReduceLoadWidth(N0.getNode()); |
| if (NarrowLoad.getNode()) { |
| SDNode* oye = N0.getNode()->getOperand(0).getNode(); |
| if (NarrowLoad.getNode() != N0.getNode()) { |
| CombineTo(N0.getNode(), NarrowLoad); |
| // CombineTo deleted the truncate, if needed, but not what's under it. |
| AddToWorkList(oye); |
| } |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| // See if the value being truncated is already sign extended. If so, just |
| // eliminate the trunc/sext pair. |
| SDValue Op = N0.getOperand(0); |
| unsigned OpBits = Op.getValueType().getScalarType().getSizeInBits(); |
| unsigned MidBits = N0.getValueType().getScalarType().getSizeInBits(); |
| unsigned DestBits = VT.getScalarType().getSizeInBits(); |
| unsigned NumSignBits = DAG.ComputeNumSignBits(Op); |
| |
| if (OpBits == DestBits) { |
| // Op is i32, Mid is i8, and Dest is i32. If Op has more than 24 sign |
| // bits, it is already ready. |
| if (NumSignBits > DestBits-MidBits) |
| return Op; |
| } else if (OpBits < DestBits) { |
| // Op is i32, Mid is i8, and Dest is i64. If Op has more than 24 sign |
| // bits, just sext from i32. |
| if (NumSignBits > OpBits-MidBits) |
| return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, Op); |
| } else { |
| // Op is i64, Mid is i8, and Dest is i32. If Op has more than 56 sign |
| // bits, just truncate to i32. |
| if (NumSignBits > OpBits-MidBits) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op); |
| } |
| |
| // fold (sext (truncate x)) -> (sextinreg x). |
| if (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, |
| N0.getValueType())) { |
| if (OpBits < DestBits) |
| Op = DAG.getNode(ISD::ANY_EXTEND, N0.getDebugLoc(), VT, Op); |
| else if (OpBits > DestBits) |
| Op = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), VT, Op); |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, Op, |
| DAG.getValueType(N0.getValueType())); |
| } |
| } |
| |
| // fold (sext (load x)) -> (sext (truncate (sextload x))) |
| // None of the supported targets knows how to perform load and sign extend |
| // on vectors in one instruction. We only perform this transformation on |
| // scalars. |
| if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::SEXTLOAD, N0.getValueType()))) { |
| bool DoXform = true; |
| SmallVector<SDNode*, 4> SetCCs; |
| if (!N0.hasOneUse()) |
| DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::SIGN_EXTEND, SetCCs, TLI); |
| if (DoXform) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| N0.getValueType(), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad); |
| CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1)); |
| ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(), |
| ISD::SIGN_EXTEND); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (sext (sextload x)) -> (sext (truncate (sextload x))) |
| // fold (sext ( extload x)) -> (sext (truncate (sextload x))) |
| if ((ISD::isSEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) && |
| ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| EVT MemVT = LN0->getMemoryVT(); |
| if ((!LegalOperations && !LN0->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::SEXTLOAD, MemVT)) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| MemVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), |
| DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad), |
| ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (sext (and/or/xor (load x), cst)) -> |
| // (and/or/xor (sextload x), (sext cst)) |
| if ((N0.getOpcode() == ISD::AND || N0.getOpcode() == ISD::OR || |
| N0.getOpcode() == ISD::XOR) && |
| isa<LoadSDNode>(N0.getOperand(0)) && |
| N0.getOperand(1).getOpcode() == ISD::Constant && |
| TLI.isLoadExtLegal(ISD::SEXTLOAD, N0.getValueType()) && |
| (!LegalOperations && TLI.isOperationLegal(N0.getOpcode(), VT))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0.getOperand(0)); |
| if (LN0->getExtensionType() != ISD::ZEXTLOAD) { |
| bool DoXform = true; |
| SmallVector<SDNode*, 4> SetCCs; |
| if (!N0.hasOneUse()) |
| DoXform = ExtendUsesToFormExtLoad(N, N0.getOperand(0), ISD::SIGN_EXTEND, |
| SetCCs, TLI); |
| if (DoXform) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, LN0->getDebugLoc(), VT, |
| LN0->getChain(), LN0->getBasePtr(), |
| LN0->getPointerInfo(), |
| LN0->getMemoryVT(), |
| LN0->isVolatile(), |
| LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue(); |
| Mask = Mask.sext(VT.getSizeInBits()); |
| SDValue And = DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, |
| ExtLoad, DAG.getConstant(Mask, VT)); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, |
| N0.getOperand(0).getDebugLoc(), |
| N0.getOperand(0).getValueType(), ExtLoad); |
| CombineTo(N, And); |
| CombineTo(N0.getOperand(0).getNode(), Trunc, ExtLoad.getValue(1)); |
| ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(), |
| ISD::SIGN_EXTEND); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| |
| if (N0.getOpcode() == ISD::SETCC) { |
| // sext(setcc) -> sext_in_reg(vsetcc) for vectors. |
| // Only do this before legalize for now. |
| if (VT.isVector() && !LegalOperations) { |
| EVT N0VT = N0.getOperand(0).getValueType(); |
| // On some architectures (such as SSE/NEON/etc) the SETCC result type is |
| // of the same size as the compared operands. Only optimize sext(setcc()) |
| // if this is the case. |
| EVT SVT = TLI.getSetCCResultType(N0VT); |
| |
| // We know that the # elements of the results is the same as the |
| // # elements of the compare (and the # elements of the compare result |
| // for that matter). Check to see that they are the same size. If so, |
| // we know that the element size of the sext'd result matches the |
| // element size of the compare operands. |
| if (VT.getSizeInBits() == SVT.getSizeInBits()) |
| return DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0), |
| N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| // If the desired elements are smaller or larger than the source |
| // elements we can use a matching integer vector type and then |
| // truncate/sign extend |
| EVT MatchingElementType = |
| EVT::getIntegerVT(*DAG.getContext(), |
| N0VT.getScalarType().getSizeInBits()); |
| EVT MatchingVectorType = |
| EVT::getVectorVT(*DAG.getContext(), MatchingElementType, |
| N0VT.getVectorNumElements()); |
| |
| if (SVT == MatchingVectorType) { |
| SDValue VsetCC = DAG.getSetCC(N->getDebugLoc(), MatchingVectorType, |
| N0.getOperand(0), N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT); |
| } |
| } |
| |
| // sext(setcc x, y, cc) -> (select_cc x, y, -1, 0, cc) |
| unsigned ElementWidth = VT.getScalarType().getSizeInBits(); |
| SDValue NegOne = |
| DAG.getConstant(APInt::getAllOnesValue(ElementWidth), VT); |
| SDValue SCC = |
| SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1), |
| NegOne, DAG.getConstant(0, VT), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get(), true); |
| if (SCC.getNode()) return SCC; |
| if (!VT.isVector() && (!LegalOperations || |
| TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(VT)))) |
| return DAG.getNode(ISD::SELECT, N->getDebugLoc(), VT, |
| DAG.getSetCC(N->getDebugLoc(), |
| TLI.getSetCCResultType(VT), |
| N0.getOperand(0), N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()), |
| NegOne, DAG.getConstant(0, VT)); |
| } |
| |
| // fold (sext x) -> (zext x) if the sign bit is known zero. |
| if ((!LegalOperations || TLI.isOperationLegal(ISD::ZERO_EXTEND, VT)) && |
| DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| // isTruncateOf - If N is a truncate of some other value, return true, record |
| // the value being truncated in Op and which of Op's bits are zero in KnownZero. |
| // This function computes KnownZero to avoid a duplicated call to |
| // ComputeMaskedBits in the caller. |
| static bool isTruncateOf(SelectionDAG &DAG, SDValue N, SDValue &Op, |
| APInt &KnownZero) { |
| APInt KnownOne; |
| if (N->getOpcode() == ISD::TRUNCATE) { |
| Op = N->getOperand(0); |
| DAG.ComputeMaskedBits(Op, KnownZero, KnownOne); |
| return true; |
| } |
| |
| if (N->getOpcode() != ISD::SETCC || N->getValueType(0) != MVT::i1 || |
| cast<CondCodeSDNode>(N->getOperand(2))->get() != ISD::SETNE) |
| return false; |
| |
| SDValue Op0 = N->getOperand(0); |
| SDValue Op1 = N->getOperand(1); |
| assert(Op0.getValueType() == Op1.getValueType()); |
| |
| ConstantSDNode *COp0 = dyn_cast<ConstantSDNode>(Op0); |
| ConstantSDNode *COp1 = dyn_cast<ConstantSDNode>(Op1); |
| if (COp0 && COp0->isNullValue()) |
| Op = Op1; |
| else if (COp1 && COp1->isNullValue()) |
| Op = Op0; |
| else |
| return false; |
| |
| DAG.ComputeMaskedBits(Op, KnownZero, KnownOne); |
| |
| if (!(KnownZero | APInt(Op.getValueSizeInBits(), 1)).isAllOnesValue()) |
| return false; |
| |
| return true; |
| } |
| |
| SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (zext c1) -> c1 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0); |
| // fold (zext (zext x)) -> (zext x) |
| // fold (zext (aext x)) -> (zext x) |
| if (N0.getOpcode() == ISD::ZERO_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND) |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, |
| N0.getOperand(0)); |
| |
| // fold (zext (truncate x)) -> (zext x) or |
| // (zext (truncate x)) -> (truncate x) |
| // This is valid when the truncated bits of x are already zero. |
| // FIXME: We should extend this to work for vectors too. |
| SDValue Op; |
| APInt KnownZero; |
| if (!VT.isVector() && isTruncateOf(DAG, N0, Op, KnownZero)) { |
| APInt TruncatedBits = |
| (Op.getValueSizeInBits() == N0.getValueSizeInBits()) ? |
| APInt(Op.getValueSizeInBits(), 0) : |
| APInt::getBitsSet(Op.getValueSizeInBits(), |
| N0.getValueSizeInBits(), |
| std::min(Op.getValueSizeInBits(), |
| VT.getSizeInBits())); |
| if (TruncatedBits == (KnownZero & TruncatedBits)) { |
| if (VT.bitsGT(Op.getValueType())) |
| return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, Op); |
| if (VT.bitsLT(Op.getValueType())) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op); |
| |
| return Op; |
| } |
| } |
| |
| // fold (zext (truncate (load x))) -> (zext (smaller load x)) |
| // fold (zext (truncate (srl (load x), c))) -> (zext (small load (x+c/n))) |
| if (N0.getOpcode() == ISD::TRUNCATE) { |
| SDValue NarrowLoad = ReduceLoadWidth(N0.getNode()); |
| if (NarrowLoad.getNode()) { |
| SDNode* oye = N0.getNode()->getOperand(0).getNode(); |
| if (NarrowLoad.getNode() != N0.getNode()) { |
| CombineTo(N0.getNode(), NarrowLoad); |
| // CombineTo deleted the truncate, if needed, but not what's under it. |
| AddToWorkList(oye); |
| } |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (zext (truncate x)) -> (and x, mask) |
| if (N0.getOpcode() == ISD::TRUNCATE && |
| (!LegalOperations || TLI.isOperationLegal(ISD::AND, VT))) { |
| |
| // fold (zext (truncate (load x))) -> (zext (smaller load x)) |
| // fold (zext (truncate (srl (load x), c))) -> (zext (smaller load (x+c/n))) |
| SDValue NarrowLoad = ReduceLoadWidth(N0.getNode()); |
| if (NarrowLoad.getNode()) { |
| SDNode* oye = N0.getNode()->getOperand(0).getNode(); |
| if (NarrowLoad.getNode() != N0.getNode()) { |
| CombineTo(N0.getNode(), NarrowLoad); |
| // CombineTo deleted the truncate, if needed, but not what's under it. |
| AddToWorkList(oye); |
| } |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| SDValue Op = N0.getOperand(0); |
| if (Op.getValueType().bitsLT(VT)) { |
| Op = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, Op); |
| AddToWorkList(Op.getNode()); |
| } else if (Op.getValueType().bitsGT(VT)) { |
| Op = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op); |
| AddToWorkList(Op.getNode()); |
| } |
| return DAG.getZeroExtendInReg(Op, N->getDebugLoc(), |
| N0.getValueType().getScalarType()); |
| } |
| |
| // Fold (zext (and (trunc x), cst)) -> (and x, cst), |
| // if either of the casts is not free. |
| if (N0.getOpcode() == ISD::AND && |
| N0.getOperand(0).getOpcode() == ISD::TRUNCATE && |
| N0.getOperand(1).getOpcode() == ISD::Constant && |
| (!TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(), |
| N0.getValueType()) || |
| !TLI.isZExtFree(N0.getValueType(), VT))) { |
| SDValue X = N0.getOperand(0).getOperand(0); |
| if (X.getValueType().bitsLT(VT)) { |
| X = DAG.getNode(ISD::ANY_EXTEND, X.getDebugLoc(), VT, X); |
| } else if (X.getValueType().bitsGT(VT)) { |
| X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X); |
| } |
| APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue(); |
| Mask = Mask.zext(VT.getSizeInBits()); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| X, DAG.getConstant(Mask, VT)); |
| } |
| |
| // fold (zext (load x)) -> (zext (truncate (zextload x))) |
| // None of the supported targets knows how to perform load and vector_zext |
| // on vectors in one instruction. We only perform this transformation on |
| // scalars. |
| if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::ZEXTLOAD, N0.getValueType()))) { |
| bool DoXform = true; |
| SmallVector<SDNode*, 4> SetCCs; |
| if (!N0.hasOneUse()) |
| DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ZERO_EXTEND, SetCCs, TLI); |
| if (DoXform) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| N0.getValueType(), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad); |
| CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1)); |
| |
| ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(), |
| ISD::ZERO_EXTEND); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (zext (and/or/xor (load x), cst)) -> |
| // (and/or/xor (zextload x), (zext cst)) |
| if ((N0.getOpcode() == ISD::AND || N0.getOpcode() == ISD::OR || |
| N0.getOpcode() == ISD::XOR) && |
| isa<LoadSDNode>(N0.getOperand(0)) && |
| N0.getOperand(1).getOpcode() == ISD::Constant && |
| TLI.isLoadExtLegal(ISD::ZEXTLOAD, N0.getValueType()) && |
| (!LegalOperations && TLI.isOperationLegal(N0.getOpcode(), VT))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0.getOperand(0)); |
| if (LN0->getExtensionType() != ISD::SEXTLOAD) { |
| bool DoXform = true; |
| SmallVector<SDNode*, 4> SetCCs; |
| if (!N0.hasOneUse()) |
| DoXform = ExtendUsesToFormExtLoad(N, N0.getOperand(0), ISD::ZERO_EXTEND, |
| SetCCs, TLI); |
| if (DoXform) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), VT, |
| LN0->getChain(), LN0->getBasePtr(), |
| LN0->getPointerInfo(), |
| LN0->getMemoryVT(), |
| LN0->isVolatile(), |
| LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue(); |
| Mask = Mask.zext(VT.getSizeInBits()); |
| SDValue And = DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, |
| ExtLoad, DAG.getConstant(Mask, VT)); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, |
| N0.getOperand(0).getDebugLoc(), |
| N0.getOperand(0).getValueType(), ExtLoad); |
| CombineTo(N, And); |
| CombineTo(N0.getOperand(0).getNode(), Trunc, ExtLoad.getValue(1)); |
| ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(), |
| ISD::ZERO_EXTEND); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| |
| // fold (zext (zextload x)) -> (zext (truncate (zextload x))) |
| // fold (zext ( extload x)) -> (zext (truncate (zextload x))) |
| if ((ISD::isZEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) && |
| ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| EVT MemVT = LN0->getMemoryVT(); |
| if ((!LegalOperations && !LN0->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT)) { |
| SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| MemVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), |
| DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), N0.getValueType(), |
| ExtLoad), |
| ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| if (N0.getOpcode() == ISD::SETCC) { |
| if (!LegalOperations && VT.isVector()) { |
| // zext(setcc) -> (and (vsetcc), (1, 1, ...) for vectors. |
| // Only do this before legalize for now. |
| EVT N0VT = N0.getOperand(0).getValueType(); |
| EVT EltVT = VT.getVectorElementType(); |
| SmallVector<SDValue,8> OneOps(VT.getVectorNumElements(), |
| DAG.getConstant(1, EltVT)); |
| if (VT.getSizeInBits() == N0VT.getSizeInBits()) |
| // We know that the # elements of the results is the same as the |
| // # elements of the compare (and the # elements of the compare result |
| // for that matter). Check to see that they are the same size. If so, |
| // we know that the element size of the sext'd result matches the |
| // element size of the compare operands. |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0), |
| N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()), |
| DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT, |
| &OneOps[0], OneOps.size())); |
| |
| // If the desired elements are smaller or larger than the source |
| // elements we can use a matching integer vector type and then |
| // truncate/sign extend |
| EVT MatchingElementType = |
| EVT::getIntegerVT(*DAG.getContext(), |
| N0VT.getScalarType().getSizeInBits()); |
| EVT MatchingVectorType = |
| EVT::getVectorVT(*DAG.getContext(), MatchingElementType, |
| N0VT.getVectorNumElements()); |
| SDValue VsetCC = |
| DAG.getSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0), |
| N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT), |
| DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT, |
| &OneOps[0], OneOps.size())); |
| } |
| |
| // zext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc |
| SDValue SCC = |
| SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1), |
| DAG.getConstant(1, VT), DAG.getConstant(0, VT), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get(), true); |
| if (SCC.getNode()) return SCC; |
| } |
| |
| // (zext (shl (zext x), cst)) -> (shl (zext x), cst) |
| if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL) && |
| isa<ConstantSDNode>(N0.getOperand(1)) && |
| N0.getOperand(0).getOpcode() == ISD::ZERO_EXTEND && |
| N0.hasOneUse()) { |
| SDValue ShAmt = N0.getOperand(1); |
| unsigned ShAmtVal = cast<ConstantSDNode>(ShAmt)->getZExtValue(); |
| if (N0.getOpcode() == ISD::SHL) { |
| SDValue InnerZExt = N0.getOperand(0); |
| // If the original shl may be shifting out bits, do not perform this |
| // transformation. |
| unsigned KnownZeroBits = InnerZExt.getValueType().getSizeInBits() - |
| InnerZExt.getOperand(0).getValueType().getSizeInBits(); |
| if (ShAmtVal > KnownZeroBits) |
| return SDValue(); |
| } |
| |
| DebugLoc DL = N->getDebugLoc(); |
| |
| // Ensure that the shift amount is wide enough for the shifted value. |
| if (VT.getSizeInBits() >= 256) |
| ShAmt = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, ShAmt); |
| |
| return DAG.getNode(N0.getOpcode(), DL, VT, |
| DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0)), |
| ShAmt); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (aext c1) -> c1 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, N0); |
| // fold (aext (aext x)) -> (aext x) |
| // fold (aext (zext x)) -> (zext x) |
| // fold (aext (sext x)) -> (sext x) |
| if (N0.getOpcode() == ISD::ANY_EXTEND || |
| N0.getOpcode() == ISD::ZERO_EXTEND || |
| N0.getOpcode() == ISD::SIGN_EXTEND) |
| return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, N0.getOperand(0)); |
| |
| // fold (aext (truncate (load x))) -> (aext (smaller load x)) |
| // fold (aext (truncate (srl (load x), c))) -> (aext (small load (x+c/n))) |
| if (N0.getOpcode() == ISD::TRUNCATE) { |
| SDValue NarrowLoad = ReduceLoadWidth(N0.getNode()); |
| if (NarrowLoad.getNode()) { |
| SDNode* oye = N0.getNode()->getOperand(0).getNode(); |
| if (NarrowLoad.getNode() != N0.getNode()) { |
| CombineTo(N0.getNode(), NarrowLoad); |
| // CombineTo deleted the truncate, if needed, but not what's under it. |
| AddToWorkList(oye); |
| } |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (aext (truncate x)) |
| if (N0.getOpcode() == ISD::TRUNCATE) { |
| SDValue TruncOp = N0.getOperand(0); |
| if (TruncOp.getValueType() == VT) |
| return TruncOp; // x iff x size == zext size. |
| if (TruncOp.getValueType().bitsGT(VT)) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, TruncOp); |
| return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, TruncOp); |
| } |
| |
| // Fold (aext (and (trunc x), cst)) -> (and x, cst) |
| // if the trunc is not free. |
| if (N0.getOpcode() == ISD::AND && |
| N0.getOperand(0).getOpcode() == ISD::TRUNCATE && |
| N0.getOperand(1).getOpcode() == ISD::Constant && |
| !TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(), |
| N0.getValueType())) { |
| SDValue X = N0.getOperand(0).getOperand(0); |
| if (X.getValueType().bitsLT(VT)) { |
| X = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, X); |
| } else if (X.getValueType().bitsGT(VT)) { |
| X = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, X); |
| } |
| APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue(); |
| Mask = Mask.zext(VT.getSizeInBits()); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| X, DAG.getConstant(Mask, VT)); |
| } |
| |
| // fold (aext (load x)) -> (aext (truncate (extload x))) |
| // None of the supported targets knows how to perform load and any_ext |
| // on vectors in one instruction. We only perform this transformation on |
| // scalars. |
| if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) { |
| bool DoXform = true; |
| SmallVector<SDNode*, 4> SetCCs; |
| if (!N0.hasOneUse()) |
| DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ANY_EXTEND, SetCCs, TLI); |
| if (DoXform) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| N0.getValueType(), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad); |
| CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1)); |
| ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(), |
| ISD::ANY_EXTEND); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| |
| // fold (aext (zextload x)) -> (aext (truncate (zextload x))) |
| // fold (aext (sextload x)) -> (aext (truncate (sextload x))) |
| // fold (aext ( extload x)) -> (aext (truncate (extload x))) |
| if (N0.getOpcode() == ISD::LOAD && |
| !ISD::isNON_EXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) && |
| N0.hasOneUse()) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| EVT MemVT = LN0->getMemoryVT(); |
| SDValue ExtLoad = DAG.getExtLoad(LN0->getExtensionType(), N->getDebugLoc(), |
| VT, LN0->getChain(), LN0->getBasePtr(), |
| LN0->getPointerInfo(), MemVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), |
| DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad), |
| ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| if (N0.getOpcode() == ISD::SETCC) { |
| // aext(setcc) -> sext_in_reg(vsetcc) for vectors. |
| // Only do this before legalize for now. |
| if (VT.isVector() && !LegalOperations) { |
| EVT N0VT = N0.getOperand(0).getValueType(); |
| // We know that the # elements of the results is the same as the |
| // # elements of the compare (and the # elements of the compare result |
| // for that matter). Check to see that they are the same size. If so, |
| // we know that the element size of the sext'd result matches the |
| // element size of the compare operands. |
| if (VT.getSizeInBits() == N0VT.getSizeInBits()) |
| return DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0), |
| N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| // If the desired elements are smaller or larger than the source |
| // elements we can use a matching integer vector type and then |
| // truncate/sign extend |
| else { |
| EVT MatchingElementType = |
| EVT::getIntegerVT(*DAG.getContext(), |
| N0VT.getScalarType().getSizeInBits()); |
| EVT MatchingVectorType = |
| EVT::getVectorVT(*DAG.getContext(), MatchingElementType, |
| N0VT.getVectorNumElements()); |
| SDValue VsetCC = |
| DAG.getSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0), |
| N0.getOperand(1), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT); |
| } |
| } |
| |
| // aext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc |
| SDValue SCC = |
| SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1), |
| DAG.getConstant(1, VT), DAG.getConstant(0, VT), |
| cast<CondCodeSDNode>(N0.getOperand(2))->get(), true); |
| if (SCC.getNode()) |
| return SCC; |
| } |
| |
| return SDValue(); |
| } |
| |
| /// GetDemandedBits - See if the specified operand can be simplified with the |
| /// knowledge that only the bits specified by Mask are used. If so, return the |
| /// simpler operand, otherwise return a null SDValue. |
| SDValue DAGCombiner::GetDemandedBits(SDValue V, const APInt &Mask) { |
| switch (V.getOpcode()) { |
| default: break; |
| case ISD::Constant: { |
| const ConstantSDNode *CV = cast<ConstantSDNode>(V.getNode()); |
| assert(CV != 0 && "Const value should be ConstSDNode."); |
| const APInt &CVal = CV->getAPIntValue(); |
| APInt NewVal = CVal & Mask; |
| if (NewVal != CVal) { |
| return DAG.getConstant(NewVal, V.getValueType()); |
| } |
| break; |
| } |
| case ISD::OR: |
| case ISD::XOR: |
| // If the LHS or RHS don't contribute bits to the or, drop them. |
| if (DAG.MaskedValueIsZero(V.getOperand(0), Mask)) |
| return V.getOperand(1); |
| if (DAG.MaskedValueIsZero(V.getOperand(1), Mask)) |
| return V.getOperand(0); |
| break; |
| case ISD::SRL: |
| // Only look at single-use SRLs. |
| if (!V.getNode()->hasOneUse()) |
| break; |
| if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(V.getOperand(1))) { |
| // See if we can recursively simplify the LHS. |
| unsigned Amt = RHSC->getZExtValue(); |
| |
| // Watch out for shift count overflow though. |
| if (Amt >= Mask.getBitWidth()) break; |
| APInt NewMask = Mask << Amt; |
| SDValue SimplifyLHS = GetDemandedBits(V.getOperand(0), NewMask); |
| if (SimplifyLHS.getNode()) |
| return DAG.getNode(ISD::SRL, V.getDebugLoc(), V.getValueType(), |
| SimplifyLHS, V.getOperand(1)); |
| } |
| } |
| return SDValue(); |
| } |
| |
| /// ReduceLoadWidth - If the result of a wider load is shifted to right of N |
| /// bits and then truncated to a narrower type and where N is a multiple |
| /// of number of bits of the narrower type, transform it to a narrower load |
| /// from address + N / num of bits of new type. If the result is to be |
| /// extended, also fold the extension to form a extending load. |
| SDValue DAGCombiner::ReduceLoadWidth(SDNode *N) { |
| unsigned Opc = N->getOpcode(); |
| |
| ISD::LoadExtType ExtType = ISD::NON_EXTLOAD; |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| EVT ExtVT = VT; |
| |
| // This transformation isn't valid for vector loads. |
| if (VT.isVector()) |
| return SDValue(); |
| |
| // Special case: SIGN_EXTEND_INREG is basically truncating to ExtVT then |
| // extended to VT. |
| if (Opc == ISD::SIGN_EXTEND_INREG) { |
| ExtType = ISD::SEXTLOAD; |
| ExtVT = cast<VTSDNode>(N->getOperand(1))->getVT(); |
| } else if (Opc == ISD::SRL) { |
| // Another special-case: SRL is basically zero-extending a narrower value. |
| ExtType = ISD::ZEXTLOAD; |
| N0 = SDValue(N, 0); |
| ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1)); |
| if (!N01) return SDValue(); |
| ExtVT = EVT::getIntegerVT(*DAG.getContext(), |
| VT.getSizeInBits() - N01->getZExtValue()); |
| } |
| if (LegalOperations && !TLI.isLoadExtLegal(ExtType, ExtVT)) |
| return SDValue(); |
| |
| unsigned EVTBits = ExtVT.getSizeInBits(); |
| |
| // Do not generate loads of non-round integer types since these can |
| // be expensive (and would be wrong if the type is not byte sized). |
| if (!ExtVT.isRound()) |
| return SDValue(); |
| |
| unsigned ShAmt = 0; |
| if (N0.getOpcode() == ISD::SRL && N0.hasOneUse()) { |
| if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) { |
| ShAmt = N01->getZExtValue(); |
| // Is the shift amount a multiple of size of VT? |
| if ((ShAmt & (EVTBits-1)) == 0) { |
| N0 = N0.getOperand(0); |
| // Is the load width a multiple of size of VT? |
| if ((N0.getValueType().getSizeInBits() & (EVTBits-1)) != 0) |
| return SDValue(); |
| } |
| |
| // At this point, we must have a load or else we can't do the transform. |
| if (!isa<LoadSDNode>(N0)) return SDValue(); |
| |
| // Because a SRL must be assumed to *need* to zero-extend the high bits |
| // (as opposed to anyext the high bits), we can't combine the zextload |
| // lowering of SRL and an sextload. |
| if (cast<LoadSDNode>(N0)->getExtensionType() == ISD::SEXTLOAD) |
| return SDValue(); |
| |
| // If the shift amount is larger than the input type then we're not |
| // accessing any of the loaded bytes. If the load was a zextload/extload |
| // then the result of the shift+trunc is zero/undef (handled elsewhere). |
| if (ShAmt >= cast<LoadSDNode>(N0)->getMemoryVT().getSizeInBits()) |
| return SDValue(); |
| } |
| } |
| |
| // If the load is shifted left (and the result isn't shifted back right), |
| // we can fold the truncate through the shift. |
| unsigned ShLeftAmt = 0; |
| if (ShAmt == 0 && N0.getOpcode() == ISD::SHL && N0.hasOneUse() && |
| ExtVT == VT && TLI.isNarrowingProfitable(N0.getValueType(), VT)) { |
| if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) { |
| ShLeftAmt = N01->getZExtValue(); |
| N0 = N0.getOperand(0); |
| } |
| } |
| |
| // If we haven't found a load, we can't narrow it. Don't transform one with |
| // multiple uses, this would require adding a new load. |
| if (!isa<LoadSDNode>(N0) || !N0.hasOneUse()) |
| return SDValue(); |
| |
| // Don't change the width of a volatile load. |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| if (LN0->isVolatile()) |
| return SDValue(); |
| |
| // Verify that we are actually reducing a load width here. |
| if (LN0->getMemoryVT().getSizeInBits() < EVTBits) |
| return SDValue(); |
| |
| // For the transform to be legal, the load must produce only two values |
| // (the value loaded and the chain). Don't transform a pre-increment |
| // load, for example, which produces an extra value. Otherwise the |
| // transformation is not equivalent, and the downstream logic to replace |
| // uses gets things wrong. |
| if (LN0->getNumValues() > 2) |
| return SDValue(); |
| |
| EVT PtrType = N0.getOperand(1).getValueType(); |
| |
| if (PtrType == MVT::Untyped || PtrType.isExtended()) |
| // It's not possible to generate a constant of extended or untyped type. |
| return SDValue(); |
| |
| // For big endian targets, we need to adjust the offset to the pointer to |
| // load the correct bytes. |
| if (TLI.isBigEndian()) { |
| unsigned LVTStoreBits = LN0->getMemoryVT().getStoreSizeInBits(); |
| unsigned EVTStoreBits = ExtVT.getStoreSizeInBits(); |
| ShAmt = LVTStoreBits - EVTStoreBits - ShAmt; |
| } |
| |
| uint64_t PtrOff = ShAmt / 8; |
| unsigned NewAlign = MinAlign(LN0->getAlignment(), PtrOff); |
| SDValue NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(), |
| PtrType, LN0->getBasePtr(), |
| DAG.getConstant(PtrOff, PtrType)); |
| AddToWorkList(NewPtr.getNode()); |
| |
| SDValue Load; |
| if (ExtType == ISD::NON_EXTLOAD) |
| Load = DAG.getLoad(VT, N0.getDebugLoc(), LN0->getChain(), NewPtr, |
| LN0->getPointerInfo().getWithOffset(PtrOff), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->isInvariant(), NewAlign); |
| else |
| Load = DAG.getExtLoad(ExtType, N0.getDebugLoc(), VT, LN0->getChain(),NewPtr, |
| LN0->getPointerInfo().getWithOffset(PtrOff), |
| ExtVT, LN0->isVolatile(), LN0->isNonTemporal(), |
| NewAlign); |
| |
| // Replace the old load's chain with the new load's chain. |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), Load.getValue(1)); |
| |
| // Shift the result left, if we've swallowed a left shift. |
| SDValue Result = Load; |
| if (ShLeftAmt != 0) { |
| EVT ShImmTy = getShiftAmountTy(Result.getValueType()); |
| if (!isUIntN(ShImmTy.getSizeInBits(), ShLeftAmt)) |
| ShImmTy = VT; |
| // If the shift amount is as large as the result size (but, presumably, |
| // no larger than the source) then the useful bits of the result are |
| // zero; we can't simply return the shortened shift, because the result |
| // of that operation is undefined. |
| if (ShLeftAmt >= VT.getSizeInBits()) |
| Result = DAG.getConstant(0, VT); |
| else |
| Result = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT, |
| Result, DAG.getConstant(ShLeftAmt, ShImmTy)); |
| } |
| |
| // Return the new loaded value. |
| return Result; |
| } |
| |
| SDValue DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| EVT VT = N->getValueType(0); |
| EVT EVT = cast<VTSDNode>(N1)->getVT(); |
| unsigned VTBits = VT.getScalarType().getSizeInBits(); |
| unsigned EVTBits = EVT.getScalarType().getSizeInBits(); |
| |
| // fold (sext_in_reg c1) -> c1 |
| if (isa<ConstantSDNode>(N0) || N0.getOpcode() == ISD::UNDEF) |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, N0, N1); |
| |
| // If the input is already sign extended, just drop the extension. |
| if (DAG.ComputeNumSignBits(N0) >= VTBits-EVTBits+1) |
| return N0; |
| |
| // fold (sext_in_reg (sext_in_reg x, VT2), VT1) -> (sext_in_reg x, minVT) pt2 |
| if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG && |
| EVT.bitsLT(cast<VTSDNode>(N0.getOperand(1))->getVT())) { |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, |
| N0.getOperand(0), N1); |
| } |
| |
| // fold (sext_in_reg (sext x)) -> (sext x) |
| // fold (sext_in_reg (aext x)) -> (sext x) |
| // if x is small enough. |
| if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND) { |
| SDValue N00 = N0.getOperand(0); |
| if (N00.getValueType().getScalarType().getSizeInBits() <= EVTBits && |
| (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND, VT))) |
| return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N00, N1); |
| } |
| |
| // fold (sext_in_reg x) -> (zext_in_reg x) if the sign bit is known zero. |
| if (DAG.MaskedValueIsZero(N0, APInt::getBitsSet(VTBits, EVTBits-1, EVTBits))) |
| return DAG.getZeroExtendInReg(N0, N->getDebugLoc(), EVT); |
| |
| // fold operands of sext_in_reg based on knowledge that the top bits are not |
| // demanded. |
| if (SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| // fold (sext_in_reg (load x)) -> (smaller sextload x) |
| // fold (sext_in_reg (srl (load x), c)) -> (smaller sextload (x+c/evtbits)) |
| SDValue NarrowLoad = ReduceLoadWidth(N); |
| if (NarrowLoad.getNode()) |
| return NarrowLoad; |
| |
| // fold (sext_in_reg (srl X, 24), i8) -> (sra X, 24) |
| // fold (sext_in_reg (srl X, 23), i8) -> (sra X, 23) iff possible. |
| // We already fold "(sext_in_reg (srl X, 25), i8) -> srl X, 25" above. |
| if (N0.getOpcode() == ISD::SRL) { |
| if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(N0.getOperand(1))) |
| if (ShAmt->getZExtValue()+EVTBits <= VTBits) { |
| // We can turn this into an SRA iff the input to the SRL is already sign |
| // extended enough. |
| unsigned InSignBits = DAG.ComputeNumSignBits(N0.getOperand(0)); |
| if (VTBits-(ShAmt->getZExtValue()+EVTBits) < InSignBits) |
| return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1)); |
| } |
| } |
| |
| // fold (sext_inreg (extload x)) -> (sextload x) |
| if (ISD::isEXTLoad(N0.getNode()) && |
| ISD::isUNINDEXEDLoad(N0.getNode()) && |
| EVT == cast<LoadSDNode>(N0)->getMemoryVT() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| EVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1)); |
| AddToWorkList(ExtLoad.getNode()); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| // fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use |
| if (ISD::isZEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) && |
| N0.hasOneUse() && |
| EVT == cast<LoadSDNode>(N0)->getMemoryVT() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| EVT, |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| // Form (sext_inreg (bswap >> 16)) or (sext_inreg (rotl (bswap) 16)) |
| if (EVTBits <= 16 && N0.getOpcode() == ISD::OR) { |
| SDValue BSwap = MatchBSwapHWordLow(N0.getNode(), N0.getOperand(0), |
| N0.getOperand(1), false); |
| if (BSwap.getNode() != 0) |
| return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, |
| BSwap, N1); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitTRUNCATE(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| bool isLE = TLI.isLittleEndian(); |
| |
| // noop truncate |
| if (N0.getValueType() == N->getValueType(0)) |
| return N0; |
| // fold (truncate c1) -> c1 |
| if (isa<ConstantSDNode>(N0)) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0); |
| // fold (truncate (truncate x)) -> (truncate x) |
| if (N0.getOpcode() == ISD::TRUNCATE) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0)); |
| // fold (truncate (ext x)) -> (ext x) or (truncate x) or x |
| if (N0.getOpcode() == ISD::ZERO_EXTEND || |
| N0.getOpcode() == ISD::SIGN_EXTEND || |
| N0.getOpcode() == ISD::ANY_EXTEND) { |
| if (N0.getOperand(0).getValueType().bitsLT(VT)) |
| // if the source is smaller than the dest, we still need an extend |
| return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, |
| N0.getOperand(0)); |
| if (N0.getOperand(0).getValueType().bitsGT(VT)) |
| // if the source is larger than the dest, than we just need the truncate |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0)); |
| // if the source and dest are the same type, we can drop both the extend |
| // and the truncate. |
| return N0.getOperand(0); |
| } |
| |
| // Fold extract-and-trunc into a narrow extract. For example: |
| // i64 x = EXTRACT_VECTOR_ELT(v2i64 val, i32 1) |
| // i32 y = TRUNCATE(i64 x) |
| // -- becomes -- |
| // v16i8 b = BITCAST (v2i64 val) |
| // i8 x = EXTRACT_VECTOR_ELT(v16i8 b, i32 8) |
| // |
| // Note: We only run this optimization after type legalization (which often |
| // creates this pattern) and before operation legalization after which |
| // we need to be more careful about the vector instructions that we generate. |
| if (N0.getOpcode() == ISD::EXTRACT_VECTOR_ELT && |
| LegalTypes && !LegalOperations && N0->hasOneUse()) { |
| |
| EVT VecTy = N0.getOperand(0).getValueType(); |
| EVT ExTy = N0.getValueType(); |
| EVT TrTy = N->getValueType(0); |
| |
| unsigned NumElem = VecTy.getVectorNumElements(); |
| unsigned SizeRatio = ExTy.getSizeInBits()/TrTy.getSizeInBits(); |
| |
| EVT NVT = EVT::getVectorVT(*DAG.getContext(), TrTy, SizeRatio * NumElem); |
| assert(NVT.getSizeInBits() == VecTy.getSizeInBits() && "Invalid Size"); |
| |
| SDValue EltNo = N0->getOperand(1); |
| if (isa<ConstantSDNode>(EltNo) && isTypeLegal(NVT)) { |
| int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue(); |
| EVT IndexTy = N0->getOperand(1).getValueType(); |
| int Index = isLE ? (Elt*SizeRatio) : (Elt*SizeRatio + (SizeRatio-1)); |
| |
| SDValue V = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), |
| NVT, N0.getOperand(0)); |
| |
| return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, |
| N->getDebugLoc(), TrTy, V, |
| DAG.getConstant(Index, IndexTy)); |
| } |
| } |
| |
| // Fold a series of buildvector, bitcast, and truncate if possible. |
| // For example fold |
| // (2xi32 trunc (bitcast ((4xi32)buildvector x, x, y, y) 2xi64)) to |
| // (2xi32 (buildvector x, y)). |
| if (Level == AfterLegalizeVectorOps && VT.isVector() && |
| N0.getOpcode() == ISD::BITCAST && N0.hasOneUse() && |
| N0.getOperand(0).getOpcode() == ISD::BUILD_VECTOR && |
| N0.getOperand(0).hasOneUse()) { |
| |
| SDValue BuildVect = N0.getOperand(0); |
| EVT BuildVectEltTy = BuildVect.getValueType().getVectorElementType(); |
| EVT TruncVecEltTy = VT.getVectorElementType(); |
| |
| // Check that the element types match. |
| if (BuildVectEltTy == TruncVecEltTy) { |
| // Now we only need to compute the offset of the truncated elements. |
| unsigned BuildVecNumElts = BuildVect.getNumOperands(); |
| unsigned TruncVecNumElts = VT.getVectorNumElements(); |
| unsigned TruncEltOffset = BuildVecNumElts / TruncVecNumElts; |
| |
| assert((BuildVecNumElts % TruncVecNumElts) == 0 && |
| "Invalid number of elements"); |
| |
| SmallVector<SDValue, 8> Opnds; |
| for (unsigned i = 0, e = BuildVecNumElts; i != e; i += TruncEltOffset) |
| Opnds.push_back(BuildVect.getOperand(i)); |
| |
| return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT, &Opnds[0], |
| Opnds.size()); |
| } |
| } |
| |
| // See if we can simplify the input to this truncate through knowledge that |
| // only the low bits are being used. |
| // For example "trunc (or (shl x, 8), y)" // -> trunc y |
| // Currently we only perform this optimization on scalars because vectors |
| // may have different active low bits. |
| if (!VT.isVector()) { |
| SDValue Shorter = |
| GetDemandedBits(N0, APInt::getLowBitsSet(N0.getValueSizeInBits(), |
| VT.getSizeInBits())); |
| if (Shorter.getNode()) |
| return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Shorter); |
| } |
| // fold (truncate (load x)) -> (smaller load x) |
| // fold (truncate (srl (load x), c)) -> (smaller load (x+c/evtbits)) |
| if (!LegalTypes || TLI.isTypeDesirableForOp(N0.getOpcode(), VT)) { |
| SDValue Reduced = ReduceLoadWidth(N); |
| if (Reduced.getNode()) |
| return Reduced; |
| } |
| // fold (trunc (concat ... x ...)) -> (concat ..., (trunc x), ...)), |
| // where ... are all 'undef'. |
| if (N0.getOpcode() == ISD::CONCAT_VECTORS && !LegalTypes) { |
| SmallVector<EVT, 8> VTs; |
| SDValue V; |
| unsigned Idx = 0; |
| unsigned NumDefs = 0; |
| |
| for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i) { |
| SDValue X = N0.getOperand(i); |
| if (X.getOpcode() != ISD::UNDEF) { |
| V = X; |
| Idx = i; |
| NumDefs++; |
| } |
| // Stop if more than one members are non-undef. |
| if (NumDefs > 1) |
| break; |
| VTs.push_back(EVT::getVectorVT(*DAG.getContext(), |
| VT.getVectorElementType(), |
| X.getValueType().getVectorNumElements())); |
| } |
| |
| if (NumDefs == 0) |
| return DAG.getUNDEF(VT); |
| |
| if (NumDefs == 1) { |
| assert(V.getNode() && "The single defined operand is empty!"); |
| SmallVector<SDValue, 8> Opnds; |
| for (unsigned i = 0, e = VTs.size(); i != e; ++i) { |
| if (i != Idx) { |
| Opnds.push_back(DAG.getUNDEF(VTs[i])); |
| continue; |
| } |
| SDValue NV = DAG.getNode(ISD::TRUNCATE, V.getDebugLoc(), VTs[i], V); |
| AddToWorkList(NV.getNode()); |
| Opnds.push_back(NV); |
| } |
| return DAG.getNode(ISD::CONCAT_VECTORS, N->getDebugLoc(), VT, |
| &Opnds[0], Opnds.size()); |
| } |
| } |
| |
| // Simplify the operands using demanded-bits information. |
| if (!VT.isVector() && |
| SimplifyDemandedBits(SDValue(N, 0))) |
| return SDValue(N, 0); |
| |
| return SDValue(); |
| } |
| |
| static SDNode *getBuildPairElt(SDNode *N, unsigned i) { |
| SDValue Elt = N->getOperand(i); |
| if (Elt.getOpcode() != ISD::MERGE_VALUES) |
| return Elt.getNode(); |
| return Elt.getOperand(Elt.getResNo()).getNode(); |
| } |
| |
| /// CombineConsecutiveLoads - build_pair (load, load) -> load |
| /// if load locations are consecutive. |
| SDValue DAGCombiner::CombineConsecutiveLoads(SDNode *N, EVT VT) { |
| assert(N->getOpcode() == ISD::BUILD_PAIR); |
| |
| LoadSDNode *LD1 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 0)); |
| LoadSDNode *LD2 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 1)); |
| if (!LD1 || !LD2 || !ISD::isNON_EXTLoad(LD1) || !LD1->hasOneUse() || |
| LD1->getPointerInfo().getAddrSpace() != |
| LD2->getPointerInfo().getAddrSpace()) |
| return SDValue(); |
| EVT LD1VT = LD1->getValueType(0); |
| |
| if (ISD::isNON_EXTLoad(LD2) && |
| LD2->hasOneUse() && |
| // If both are volatile this would reduce the number of volatile loads. |
| // If one is volatile it might be ok, but play conservative and bail out. |
| !LD1->isVolatile() && |
| !LD2->isVolatile() && |
| DAG.isConsecutiveLoad(LD2, LD1, LD1VT.getSizeInBits()/8, 1)) { |
| unsigned Align = LD1->getAlignment(); |
| unsigned NewAlign = TLI.getDataLayout()-> |
| getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext())); |
| |
| if (NewAlign <= Align && |
| (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT))) |
| return DAG.getLoad(VT, N->getDebugLoc(), LD1->getChain(), |
| LD1->getBasePtr(), LD1->getPointerInfo(), |
| false, false, false, Align); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitBITCAST(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| // If the input is a BUILD_VECTOR with all constant elements, fold this now. |
| // Only do this before legalize, since afterward the target may be depending |
| // on the bitconvert. |
| // First check to see if this is all constant. |
| if (!LegalTypes && |
| N0.getOpcode() == ISD::BUILD_VECTOR && N0.getNode()->hasOneUse() && |
| VT.isVector()) { |
| bool isSimple = true; |
| for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i) |
| if (N0.getOperand(i).getOpcode() != ISD::UNDEF && |
| N0.getOperand(i).getOpcode() != ISD::Constant && |
| N0.getOperand(i).getOpcode() != ISD::ConstantFP) { |
| isSimple = false; |
| break; |
| } |
| |
| EVT DestEltVT = N->getValueType(0).getVectorElementType(); |
| assert(!DestEltVT.isVector() && |
| "Element type of vector ValueType must not be vector!"); |
| if (isSimple) |
| return ConstantFoldBITCASTofBUILD_VECTOR(N0.getNode(), DestEltVT); |
| } |
| |
| // If the input is a constant, let getNode fold it. |
| if (isa<ConstantSDNode>(N0) || isa<ConstantFPSDNode>(N0)) { |
| SDValue Res = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT, N0); |
| if (Res.getNode() != N) { |
| if (!LegalOperations || |
| TLI.isOperationLegal(Res.getNode()->getOpcode(), VT)) |
| return Res; |
| |
| // Folding it resulted in an illegal node, and it's too late to |
| // do that. Clean up the old node and forego the transformation. |
| // Ideally this won't happen very often, because instcombine |
| // and the earlier dagcombine runs (where illegal nodes are |
| // permitted) should have folded most of them already. |
| DAG.DeleteNode(Res.getNode()); |
| } |
| } |
| |
| // (conv (conv x, t1), t2) -> (conv x, t2) |
| if (N0.getOpcode() == ISD::BITCAST) |
| return DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT, |
| N0.getOperand(0)); |
| |
| // fold (conv (load x)) -> (load (conv*)x) |
| // If the resultant load doesn't need a higher alignment than the original! |
| if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() && |
| // Do not change the width of a volatile load. |
| !cast<LoadSDNode>(N0)->isVolatile() && |
| (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| unsigned Align = TLI.getDataLayout()-> |
| getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext())); |
| unsigned OrigAlign = LN0->getAlignment(); |
| |
| if (Align <= OrigAlign) { |
| SDValue Load = DAG.getLoad(VT, N->getDebugLoc(), LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->isInvariant(), OrigAlign); |
| AddToWorkList(N); |
| CombineTo(N0.getNode(), |
| DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), |
| N0.getValueType(), Load), |
| Load.getValue(1)); |
| return Load; |
| } |
| } |
| |
| // fold (bitconvert (fneg x)) -> (xor (bitconvert x), signbit) |
| // fold (bitconvert (fabs x)) -> (and (bitconvert x), (not signbit)) |
| // This often reduces constant pool loads. |
| if (((N0.getOpcode() == ISD::FNEG && !TLI.isFNegFree(VT)) || |
| (N0.getOpcode() == ISD::FABS && !TLI.isFAbsFree(VT))) && |
| N0.getNode()->hasOneUse() && VT.isInteger() && |
| !VT.isVector() && !N0.getValueType().isVector()) { |
| SDValue NewConv = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), VT, |
| N0.getOperand(0)); |
| AddToWorkList(NewConv.getNode()); |
| |
| APInt SignBit = APInt::getSignBit(VT.getSizeInBits()); |
| if (N0.getOpcode() == ISD::FNEG) |
| return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, |
| NewConv, DAG.getConstant(SignBit, VT)); |
| assert(N0.getOpcode() == ISD::FABS); |
| return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, |
| NewConv, DAG.getConstant(~SignBit, VT)); |
| } |
| |
| // fold (bitconvert (fcopysign cst, x)) -> |
| // (or (and (bitconvert x), sign), (and cst, (not sign))) |
| // Note that we don't handle (copysign x, cst) because this can always be |
| // folded to an fneg or fabs. |
| if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse() && |
| isa<ConstantFPSDNode>(N0.getOperand(0)) && |
| VT.isInteger() && !VT.isVector()) { |
| unsigned OrigXWidth = N0.getOperand(1).getValueType().getSizeInBits(); |
| EVT IntXVT = EVT::getIntegerVT(*DAG.getContext(), OrigXWidth); |
| if (isTypeLegal(IntXVT)) { |
| SDValue X = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), |
| IntXVT, N0.getOperand(1)); |
| AddToWorkList(X.getNode()); |
| |
| // If X has a different width than the result/lhs, sext it or truncate it. |
| unsigned VTWidth = VT.getSizeInBits(); |
| if (OrigXWidth < VTWidth) { |
| X = DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, X); |
| AddToWorkList(X.getNode()); |
| } else if (OrigXWidth > VTWidth) { |
| // To get the sign bit in the right place, we have to shift it right |
| // before truncating. |
| X = DAG.getNode(ISD::SRL, X.getDebugLoc(), |
| X.getValueType(), X, |
| DAG.getConstant(OrigXWidth-VTWidth, X.getValueType())); |
| AddToWorkList(X.getNode()); |
| X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X); |
| AddToWorkList(X.getNode()); |
| } |
| |
| APInt SignBit = APInt::getSignBit(VT.getSizeInBits()); |
| X = DAG.getNode(ISD::AND, X.getDebugLoc(), VT, |
| X, DAG.getConstant(SignBit, VT)); |
| AddToWorkList(X.getNode()); |
| |
| SDValue Cst = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), |
| VT, N0.getOperand(0)); |
| Cst = DAG.getNode(ISD::AND, Cst.getDebugLoc(), VT, |
| Cst, DAG.getConstant(~SignBit, VT)); |
| AddToWorkList(Cst.getNode()); |
| |
| return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, X, Cst); |
| } |
| } |
| |
| // bitconvert(build_pair(ld, ld)) -> ld iff load locations are consecutive. |
| if (N0.getOpcode() == ISD::BUILD_PAIR) { |
| SDValue CombineLD = CombineConsecutiveLoads(N0.getNode(), VT); |
| if (CombineLD.getNode()) |
| return CombineLD; |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitBUILD_PAIR(SDNode *N) { |
| EVT VT = N->getValueType(0); |
| return CombineConsecutiveLoads(N, VT); |
| } |
| |
| /// ConstantFoldBITCASTofBUILD_VECTOR - We know that BV is a build_vector |
| /// node with Constant, ConstantFP or Undef operands. DstEltVT indicates the |
| /// destination element value type. |
| SDValue DAGCombiner:: |
| ConstantFoldBITCASTofBUILD_VECTOR(SDNode *BV, EVT DstEltVT) { |
| EVT SrcEltVT = BV->getValueType(0).getVectorElementType(); |
| |
| // If this is already the right type, we're done. |
| if (SrcEltVT == DstEltVT) return SDValue(BV, 0); |
| |
| unsigned SrcBitSize = SrcEltVT.getSizeInBits(); |
| unsigned DstBitSize = DstEltVT.getSizeInBits(); |
| |
| // If this is a conversion of N elements of one type to N elements of another |
| // type, convert each element. This handles FP<->INT cases. |
| if (SrcBitSize == DstBitSize) { |
| EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT, |
| BV->getValueType(0).getVectorNumElements()); |
| |
| // Due to the FP element handling below calling this routine recursively, |
| // we can end up with a scalar-to-vector node here. |
| if (BV->getOpcode() == ISD::SCALAR_TO_VECTOR) |
| return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT, |
| DAG.getNode(ISD::BITCAST, BV->getDebugLoc(), |
| DstEltVT, BV->getOperand(0))); |
| |
| SmallVector<SDValue, 8> Ops; |
| for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) { |
| SDValue Op = BV->getOperand(i); |
| // If the vector element type is not legal, the BUILD_VECTOR operands |
| // are promoted and implicitly truncated. Make that explicit here. |
| if (Op.getValueType() != SrcEltVT) |
| Op = DAG.getNode(ISD::TRUNCATE, BV->getDebugLoc(), SrcEltVT, Op); |
| Ops.push_back(DAG.getNode(ISD::BITCAST, BV->getDebugLoc(), |
| DstEltVT, Op)); |
| AddToWorkList(Ops.back().getNode()); |
| } |
| return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT, |
| &Ops[0], Ops.size()); |
| } |
| |
| // Otherwise, we're growing or shrinking the elements. To avoid having to |
| // handle annoying details of growing/shrinking FP values, we convert them to |
| // int first. |
| if (SrcEltVT.isFloatingPoint()) { |
| // Convert the input float vector to a int vector where the elements are the |
| // same sizes. |
| assert((SrcEltVT == MVT::f32 || SrcEltVT == MVT::f64) && "Unknown FP VT!"); |
| EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), SrcEltVT.getSizeInBits()); |
| BV = ConstantFoldBITCASTofBUILD_VECTOR(BV, IntVT).getNode(); |
| SrcEltVT = IntVT; |
| } |
| |
| // Now we know the input is an integer vector. If the output is a FP type, |
| // convert to integer first, then to FP of the right size. |
| if (DstEltVT.isFloatingPoint()) { |
| assert((DstEltVT == MVT::f32 || DstEltVT == MVT::f64) && "Unknown FP VT!"); |
| EVT TmpVT = EVT::getIntegerVT(*DAG.getContext(), DstEltVT.getSizeInBits()); |
| SDNode *Tmp = ConstantFoldBITCASTofBUILD_VECTOR(BV, TmpVT).getNode(); |
| |
| // Next, convert to FP elements of the same size. |
| return ConstantFoldBITCASTofBUILD_VECTOR(Tmp, DstEltVT); |
| } |
| |
| // Okay, we know the src/dst types are both integers of differing types. |
| // Handling growing first. |
| assert(SrcEltVT.isInteger() && DstEltVT.isInteger()); |
| if (SrcBitSize < DstBitSize) { |
| unsigned NumInputsPerOutput = DstBitSize/SrcBitSize; |
| |
| SmallVector<SDValue, 8> Ops; |
| for (unsigned i = 0, e = BV->getNumOperands(); i != e; |
| i += NumInputsPerOutput) { |
| bool isLE = TLI.isLittleEndian(); |
| APInt NewBits = APInt(DstBitSize, 0); |
| bool EltIsUndef = true; |
| for (unsigned j = 0; j != NumInputsPerOutput; ++j) { |
| // Shift the previously computed bits over. |
| NewBits <<= SrcBitSize; |
| SDValue Op = BV->getOperand(i+ (isLE ? (NumInputsPerOutput-j-1) : j)); |
| if (Op.getOpcode() == ISD::UNDEF) continue; |
| EltIsUndef = false; |
| |
| NewBits |= cast<ConstantSDNode>(Op)->getAPIntValue(). |
| zextOrTrunc(SrcBitSize).zext(DstBitSize); |
| } |
| |
| if (EltIsUndef) |
| Ops.push_back(DAG.getUNDEF(DstEltVT)); |
| else |
| Ops.push_back(DAG.getConstant(NewBits, DstEltVT)); |
| } |
| |
| EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT, Ops.size()); |
| return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT, |
| &Ops[0], Ops.size()); |
| } |
| |
| // Finally, this must be the case where we are shrinking elements: each input |
| // turns into multiple outputs. |
| bool isS2V = ISD::isScalarToVector(BV); |
| unsigned NumOutputsPerInput = SrcBitSize/DstBitSize; |
| EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT, |
| NumOutputsPerInput*BV->getNumOperands()); |
| SmallVector<SDValue, 8> Ops; |
| |
| for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) { |
| if (BV->getOperand(i).getOpcode() == ISD::UNDEF) { |
| for (unsigned j = 0; j != NumOutputsPerInput; ++j) |
| Ops.push_back(DAG.getUNDEF(DstEltVT)); |
| continue; |
| } |
| |
| APInt OpVal = cast<ConstantSDNode>(BV->getOperand(i))-> |
| getAPIntValue().zextOrTrunc(SrcBitSize); |
| |
| for (unsigned j = 0; j != NumOutputsPerInput; ++j) { |
| APInt ThisVal = OpVal.trunc(DstBitSize); |
| Ops.push_back(DAG.getConstant(ThisVal, DstEltVT)); |
| if (isS2V && i == 0 && j == 0 && ThisVal.zext(SrcBitSize) == OpVal) |
| // Simply turn this into a SCALAR_TO_VECTOR of the new type. |
| return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT, |
| Ops[0]); |
| OpVal = OpVal.lshr(DstBitSize); |
| } |
| |
| // For big endian targets, swap the order of the pieces of each element. |
| if (TLI.isBigEndian()) |
| std::reverse(Ops.end()-NumOutputsPerInput, Ops.end()); |
| } |
| |
| return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT, |
| &Ops[0], Ops.size()); |
| } |
| |
| SDValue DAGCombiner::visitFADD(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (fadd c1, c2) -> c1 + c2 |
| if (N0CFP && N1CFP) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N1); |
| // canonicalize constant to RHS |
| if (N0CFP && !N1CFP) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N0); |
| // fold (fadd A, 0) -> A |
| if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && |
| N1CFP->getValueAPF().isZero()) |
| return N0; |
| // fold (fadd A, (fneg B)) -> (fsub A, B) |
| if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) && |
| isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options) == 2) |
| return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, |
| GetNegatedExpression(N1, DAG, LegalOperations)); |
| // fold (fadd (fneg A), B) -> (fsub B, A) |
| if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) && |
| isNegatibleForFree(N0, LegalOperations, TLI, &DAG.getTarget().Options) == 2) |
| return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N1, |
| GetNegatedExpression(N0, DAG, LegalOperations)); |
| |
| // If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2)) |
| if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && |
| N0.getOpcode() == ISD::FADD && N0.getNode()->hasOneUse() && |
| isa<ConstantFPSDNode>(N0.getOperand(1))) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| N0.getOperand(1), N1)); |
| |
| // If allow, fold (fadd (fneg x), x) -> 0.0 |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N0.getOpcode() == ISD::FNEG && N0.getOperand(0) == N1) { |
| return DAG.getConstantFP(0.0, VT); |
| } |
| |
| // If allow, fold (fadd x, (fneg x)) -> 0.0 |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N1.getOpcode() == ISD::FNEG && N1.getOperand(0) == N0) { |
| return DAG.getConstantFP(0.0, VT); |
| } |
| |
| // In unsafe math mode, we can fold chains of FADD's of the same value |
| // into multiplications. This transform is not safe in general because |
| // we are reducing the number of rounding steps. |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| TLI.isOperationLegalOrCustom(ISD::FMUL, VT) && |
| !N0CFP && !N1CFP) { |
| if (N0.getOpcode() == ISD::FMUL) { |
| ConstantFPSDNode *CFP00 = dyn_cast<ConstantFPSDNode>(N0.getOperand(0)); |
| ConstantFPSDNode *CFP01 = dyn_cast<ConstantFPSDNode>(N0.getOperand(1)); |
| |
| // (fadd (fmul c, x), x) -> (fmul c+1, x) |
| if (CFP00 && !CFP01 && N0.getOperand(1) == N1) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP00, 0), |
| DAG.getConstantFP(1.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N1, NewCFP); |
| } |
| |
| // (fadd (fmul x, c), x) -> (fmul c+1, x) |
| if (CFP01 && !CFP00 && N0.getOperand(0) == N1) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP01, 0), |
| DAG.getConstantFP(1.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N1, NewCFP); |
| } |
| |
| // (fadd (fmul c, x), (fadd x, x)) -> (fmul c+2, x) |
| if (CFP00 && !CFP01 && N1.getOpcode() == ISD::FADD && |
| N1.getOperand(0) == N1.getOperand(1) && |
| N0.getOperand(1) == N1.getOperand(0)) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP00, 0), |
| DAG.getConstantFP(2.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(1), NewCFP); |
| } |
| |
| // (fadd (fmul x, c), (fadd x, x)) -> (fmul c+2, x) |
| if (CFP01 && !CFP00 && N1.getOpcode() == ISD::FADD && |
| N1.getOperand(0) == N1.getOperand(1) && |
| N0.getOperand(0) == N1.getOperand(0)) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP01, 0), |
| DAG.getConstantFP(2.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(0), NewCFP); |
| } |
| } |
| |
| if (N1.getOpcode() == ISD::FMUL) { |
| ConstantFPSDNode *CFP10 = dyn_cast<ConstantFPSDNode>(N1.getOperand(0)); |
| ConstantFPSDNode *CFP11 = dyn_cast<ConstantFPSDNode>(N1.getOperand(1)); |
| |
| // (fadd x, (fmul c, x)) -> (fmul c+1, x) |
| if (CFP10 && !CFP11 && N1.getOperand(1) == N0) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP10, 0), |
| DAG.getConstantFP(1.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0, NewCFP); |
| } |
| |
| // (fadd x, (fmul x, c)) -> (fmul c+1, x) |
| if (CFP11 && !CFP10 && N1.getOperand(0) == N0) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP11, 0), |
| DAG.getConstantFP(1.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0, NewCFP); |
| } |
| |
| |
| // (fadd (fadd x, x), (fmul c, x)) -> (fmul c+2, x) |
| if (CFP10 && !CFP11 && N1.getOpcode() == ISD::FADD && |
| N1.getOperand(0) == N1.getOperand(1) && |
| N0.getOperand(1) == N1.getOperand(0)) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP10, 0), |
| DAG.getConstantFP(2.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(1), NewCFP); |
| } |
| |
| // (fadd (fadd x, x), (fmul x, c)) -> (fmul c+2, x) |
| if (CFP11 && !CFP10 && N1.getOpcode() == ISD::FADD && |
| N1.getOperand(0) == N1.getOperand(1) && |
| N0.getOperand(0) == N1.getOperand(0)) { |
| SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, |
| SDValue(CFP11, 0), |
| DAG.getConstantFP(2.0, VT)); |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(0), NewCFP); |
| } |
| } |
| |
| if (N0.getOpcode() == ISD::FADD) { |
| ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N0.getOperand(0)); |
| // (fadd (fadd x, x), x) -> (fmul 3.0, x) |
| if (!CFP && N0.getOperand(0) == N0.getOperand(1) && |
| (N0.getOperand(0) == N1)) { |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N1, DAG.getConstantFP(3.0, VT)); |
| } |
| } |
| |
| if (N1.getOpcode() == ISD::FADD) { |
| ConstantFPSDNode *CFP10 = dyn_cast<ConstantFPSDNode>(N1.getOperand(0)); |
| // (fadd x, (fadd x, x)) -> (fmul 3.0, x) |
| if (!CFP10 && N1.getOperand(0) == N1.getOperand(1) && |
| N1.getOperand(0) == N0) { |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0, DAG.getConstantFP(3.0, VT)); |
| } |
| } |
| |
| // (fadd (fadd x, x), (fadd x, x)) -> (fmul 4.0, x) |
| if (N0.getOpcode() == ISD::FADD && N1.getOpcode() == ISD::FADD && |
| N0.getOperand(0) == N0.getOperand(1) && |
| N1.getOperand(0) == N1.getOperand(1) && |
| N0.getOperand(0) == N1.getOperand(0)) { |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(0), |
| DAG.getConstantFP(4.0, VT)); |
| } |
| } |
| |
| // FADD -> FMA combines: |
| if ((DAG.getTarget().Options.AllowFPOpFusion == FPOpFusion::Fast || |
| DAG.getTarget().Options.UnsafeFPMath) && |
| DAG.getTarget().getTargetLowering()->isFMAFasterThanMulAndAdd(VT) && |
| TLI.isOperationLegalOrCustom(ISD::FMA, VT)) { |
| |
| // fold (fadd (fmul x, y), z) -> (fma x, y, z) |
| if (N0.getOpcode() == ISD::FMUL && N0->hasOneUse()) { |
| return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT, |
| N0.getOperand(0), N0.getOperand(1), N1); |
| } |
| |
| // fold (fadd x, (fmul y, z)) -> (fma y, z, x) |
| // Note: Commutes FADD operands. |
| if (N1.getOpcode() == ISD::FMUL && N1->hasOneUse()) { |
| return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT, |
| N1.getOperand(0), N1.getOperand(1), N0); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFSUB(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| DebugLoc dl = N->getDebugLoc(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (fsub c1, c2) -> c1-c2 |
| if (N0CFP && N1CFP) |
| return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, N1); |
| // fold (fsub A, 0) -> A |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N1CFP && N1CFP->getValueAPF().isZero()) |
| return N0; |
| // fold (fsub 0, B) -> -B |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N0CFP && N0CFP->getValueAPF().isZero()) { |
| if (isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options)) |
| return GetNegatedExpression(N1, DAG, LegalOperations); |
| if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT)) |
| return DAG.getNode(ISD::FNEG, dl, VT, N1); |
| } |
| // fold (fsub A, (fneg B)) -> (fadd A, B) |
| if (isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options)) |
| return DAG.getNode(ISD::FADD, dl, VT, N0, |
| GetNegatedExpression(N1, DAG, LegalOperations)); |
| |
| // If 'unsafe math' is enabled, fold |
| // (fsub x, x) -> 0.0 & |
| // (fsub x, (fadd x, y)) -> (fneg y) & |
| // (fsub x, (fadd y, x)) -> (fneg y) |
| if (DAG.getTarget().Options.UnsafeFPMath) { |
| if (N0 == N1) |
| return DAG.getConstantFP(0.0f, VT); |
| |
| if (N1.getOpcode() == ISD::FADD) { |
| SDValue N10 = N1->getOperand(0); |
| SDValue N11 = N1->getOperand(1); |
| |
| if (N10 == N0 && isNegatibleForFree(N11, LegalOperations, TLI, |
| &DAG.getTarget().Options)) |
| return GetNegatedExpression(N11, DAG, LegalOperations); |
| else if (N11 == N0 && isNegatibleForFree(N10, LegalOperations, TLI, |
| &DAG.getTarget().Options)) |
| return GetNegatedExpression(N10, DAG, LegalOperations); |
| } |
| } |
| |
| // FSUB -> FMA combines: |
| if ((DAG.getTarget().Options.AllowFPOpFusion == FPOpFusion::Fast || |
| DAG.getTarget().Options.UnsafeFPMath) && |
| DAG.getTarget().getTargetLowering()->isFMAFasterThanMulAndAdd(VT) && |
| TLI.isOperationLegalOrCustom(ISD::FMA, VT)) { |
| |
| // fold (fsub (fmul x, y), z) -> (fma x, y, (fneg z)) |
| if (N0.getOpcode() == ISD::FMUL && N0->hasOneUse()) { |
| return DAG.getNode(ISD::FMA, dl, VT, |
| N0.getOperand(0), N0.getOperand(1), |
| DAG.getNode(ISD::FNEG, dl, VT, N1)); |
| } |
| |
| // fold (fsub x, (fmul y, z)) -> (fma (fneg y), z, x) |
| // Note: Commutes FSUB operands. |
| if (N1.getOpcode() == ISD::FMUL && N1->hasOneUse()) { |
| return DAG.getNode(ISD::FMA, dl, VT, |
| DAG.getNode(ISD::FNEG, dl, VT, |
| N1.getOperand(0)), |
| N1.getOperand(1), N0); |
| } |
| |
| // fold (fsub (-(fmul, x, y)), z) -> (fma (fneg x), y, (fneg z)) |
| if (N0.getOpcode() == ISD::FNEG && |
| N0.getOperand(0).getOpcode() == ISD::FMUL && |
| N0->hasOneUse() && N0.getOperand(0).hasOneUse()) { |
| SDValue N00 = N0.getOperand(0).getOperand(0); |
| SDValue N01 = N0.getOperand(0).getOperand(1); |
| return DAG.getNode(ISD::FMA, dl, VT, |
| DAG.getNode(ISD::FNEG, dl, VT, N00), N01, |
| DAG.getNode(ISD::FNEG, dl, VT, N1)); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFMUL(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| const TargetLowering &TLI = DAG.getTargetLoweringInfo(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (fmul c1, c2) -> c1*c2 |
| if (N0CFP && N1CFP) |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0, N1); |
| // canonicalize constant to RHS |
| if (N0CFP && !N1CFP) |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N1, N0); |
| // fold (fmul A, 0) -> 0 |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N1CFP && N1CFP->getValueAPF().isZero()) |
| return N1; |
| // fold (fmul A, 0) -> 0, vector edition. |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| ISD::isBuildVectorAllZeros(N1.getNode())) |
| return N1; |
| // fold (fmul A, 1.0) -> A |
| if (N1CFP && N1CFP->isExactlyValue(1.0)) |
| return N0; |
| // fold (fmul X, 2.0) -> (fadd X, X) |
| if (N1CFP && N1CFP->isExactlyValue(+2.0)) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N0); |
| // fold (fmul X, -1.0) -> (fneg X) |
| if (N1CFP && N1CFP->isExactlyValue(-1.0)) |
| if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT)) |
| return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N0); |
| |
| // fold (fmul (fneg X), (fneg Y)) -> (fmul X, Y) |
| if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, TLI, |
| &DAG.getTarget().Options)) { |
| if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, TLI, |
| &DAG.getTarget().Options)) { |
| // Both can be negated for free, check to see if at least one is cheaper |
| // negated. |
| if (LHSNeg == 2 || RHSNeg == 2) |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| GetNegatedExpression(N0, DAG, LegalOperations), |
| GetNegatedExpression(N1, DAG, LegalOperations)); |
| } |
| } |
| |
| // If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2)) |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N1CFP && N0.getOpcode() == ISD::FMUL && |
| N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1))) |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(1), N1)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFMA(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue N2 = N->getOperand(2); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| DebugLoc dl = N->getDebugLoc(); |
| |
| if (DAG.getTarget().Options.UnsafeFPMath) { |
| if (N0CFP && N0CFP->isZero()) |
| return N2; |
| if (N1CFP && N1CFP->isZero()) |
| return N2; |
| } |
| if (N0CFP && N0CFP->isExactlyValue(1.0)) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N2); |
| if (N1CFP && N1CFP->isExactlyValue(1.0)) |
| return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N2); |
| |
| // Canonicalize (fma c, x, y) -> (fma x, c, y) |
| if (N0CFP && !N1CFP) |
| return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT, N1, N0, N2); |
| |
| // (fma x, c1, (fmul x, c2)) -> (fmul x, c1+c2) |
| if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && |
| N2.getOpcode() == ISD::FMUL && |
| N0 == N2.getOperand(0) && |
| N2.getOperand(1).getOpcode() == ISD::ConstantFP) { |
| return DAG.getNode(ISD::FMUL, dl, VT, N0, |
| DAG.getNode(ISD::FADD, dl, VT, N1, N2.getOperand(1))); |
| } |
| |
| |
| // (fma (fmul x, c1), c2, y) -> (fma x, c1*c2, y) |
| if (DAG.getTarget().Options.UnsafeFPMath && |
| N0.getOpcode() == ISD::FMUL && N1CFP && |
| N0.getOperand(1).getOpcode() == ISD::ConstantFP) { |
| return DAG.getNode(ISD::FMA, dl, VT, |
| N0.getOperand(0), |
| DAG.getNode(ISD::FMUL, dl, VT, N1, N0.getOperand(1)), |
| N2); |
| } |
| |
| // (fma x, 1, y) -> (fadd x, y) |
| // (fma x, -1, y) -> (fadd (fneg x), y) |
| if (N1CFP) { |
| if (N1CFP->isExactlyValue(1.0)) |
| return DAG.getNode(ISD::FADD, dl, VT, N0, N2); |
| |
| if (N1CFP->isExactlyValue(-1.0) && |
| (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))) { |
| SDValue RHSNeg = DAG.getNode(ISD::FNEG, dl, VT, N0); |
| AddToWorkList(RHSNeg.getNode()); |
| return DAG.getNode(ISD::FADD, dl, VT, N2, RHSNeg); |
| } |
| } |
| |
| // (fma x, c, x) -> (fmul x, (c+1)) |
| if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && N0 == N2) { |
| return DAG.getNode(ISD::FMUL, dl, VT, |
| N0, |
| DAG.getNode(ISD::FADD, dl, VT, |
| N1, DAG.getConstantFP(1.0, VT))); |
| } |
| |
| // (fma x, c, (fneg x)) -> (fmul x, (c-1)) |
| if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && |
| N2.getOpcode() == ISD::FNEG && N2.getOperand(0) == N0) { |
| return DAG.getNode(ISD::FMUL, dl, VT, |
| N0, |
| DAG.getNode(ISD::FADD, dl, VT, |
| N1, DAG.getConstantFP(-1.0, VT))); |
| } |
| |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFDIV(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| const TargetLowering &TLI = DAG.getTargetLoweringInfo(); |
| |
| // fold vector ops |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVBinOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (fdiv c1, c2) -> c1/c2 |
| if (N0CFP && N1CFP) |
| return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT, N0, N1); |
| |
| // fold (fdiv X, c2) -> fmul X, 1/c2 if losing precision is acceptable. |
| if (N1CFP && DAG.getTarget().Options.UnsafeFPMath) { |
| // Compute the reciprocal 1.0 / c2. |
| APFloat N1APF = N1CFP->getValueAPF(); |
| APFloat Recip(N1APF.getSemantics(), 1); // 1.0 |
| APFloat::opStatus st = Recip.divide(N1APF, APFloat::rmNearestTiesToEven); |
| // Only do the transform if the reciprocal is a legal fp immediate that |
| // isn't too nasty (eg NaN, denormal, ...). |
| if ((st == APFloat::opOK || st == APFloat::opInexact) && // Not too nasty |
| (!LegalOperations || |
| // FIXME: custom lowering of ConstantFP might fail (see e.g. ARM |
| // backend)... we should handle this gracefully after Legalize. |
| // TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT) || |
| TLI.isOperationLegal(llvm::ISD::ConstantFP, VT) || |
| TLI.isFPImmLegal(Recip, VT))) |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0, |
| DAG.getConstantFP(Recip, VT)); |
| } |
| |
| // (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y) |
| if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, TLI, |
| &DAG.getTarget().Options)) { |
| if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, TLI, |
| &DAG.getTarget().Options)) { |
| // Both can be negated for free, check to see if at least one is cheaper |
| // negated. |
| if (LHSNeg == 2 || RHSNeg == 2) |
| return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT, |
| GetNegatedExpression(N0, DAG, LegalOperations), |
| GetNegatedExpression(N1, DAG, LegalOperations)); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFREM(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| |
| // fold (frem c1, c2) -> fmod(c1,c2) |
| if (N0CFP && N1CFP) |
| return DAG.getNode(ISD::FREM, N->getDebugLoc(), VT, N0, N1); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFCOPYSIGN(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1); |
| EVT VT = N->getValueType(0); |
| |
| if (N0CFP && N1CFP) // Constant fold |
| return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, N0, N1); |
| |
| if (N1CFP) { |
| const APFloat& V = N1CFP->getValueAPF(); |
| // copysign(x, c1) -> fabs(x) iff ispos(c1) |
| // copysign(x, c1) -> fneg(fabs(x)) iff isneg(c1) |
| if (!V.isNegative()) { |
| if (!LegalOperations || TLI.isOperationLegal(ISD::FABS, VT)) |
| return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0); |
| } else { |
| if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT)) |
| return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, |
| DAG.getNode(ISD::FABS, N0.getDebugLoc(), VT, N0)); |
| } |
| } |
| |
| // copysign(fabs(x), y) -> copysign(x, y) |
| // copysign(fneg(x), y) -> copysign(x, y) |
| // copysign(copysign(x,z), y) -> copysign(x, y) |
| if (N0.getOpcode() == ISD::FABS || N0.getOpcode() == ISD::FNEG || |
| N0.getOpcode() == ISD::FCOPYSIGN) |
| return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, |
| N0.getOperand(0), N1); |
| |
| // copysign(x, abs(y)) -> abs(x) |
| if (N1.getOpcode() == ISD::FABS) |
| return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0); |
| |
| // copysign(x, copysign(y,z)) -> copysign(x, z) |
| if (N1.getOpcode() == ISD::FCOPYSIGN) |
| return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, |
| N0, N1.getOperand(1)); |
| |
| // copysign(x, fp_extend(y)) -> copysign(x, y) |
| // copysign(x, fp_round(y)) -> copysign(x, y) |
| if (N1.getOpcode() == ISD::FP_EXTEND || N1.getOpcode() == ISD::FP_ROUND) |
| return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, |
| N0, N1.getOperand(0)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitSINT_TO_FP(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| EVT OpVT = N0.getValueType(); |
| |
| // fold (sint_to_fp c1) -> c1fp |
| if (N0C && |
| // ...but only if the target supports immediate floating-point values |
| (!LegalOperations || |
| TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) |
| return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0); |
| |
| // If the input is a legal type, and SINT_TO_FP is not legal on this target, |
| // but UINT_TO_FP is legal on this target, try to convert. |
| if (!TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT) && |
| TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT)) { |
| // If the sign bit is known to be zero, we can change this to UINT_TO_FP. |
| if (DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0); |
| } |
| |
| // The next optimizations are desireable only if SELECT_CC can be lowered. |
| // Check against MVT::Other for SELECT_CC, which is a workaround for targets |
| // having to say they don't support SELECT_CC on every type the DAG knows |
| // about, since there is no way to mark an opcode illegal at all value types |
| // (See also visitSELECT) |
| if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other)) { |
| // fold (sint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc) |
| if (N0.getOpcode() == ISD::SETCC && N0.getValueType() == MVT::i1 && |
| !VT.isVector() && |
| (!LegalOperations || |
| TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { |
| SDValue Ops[] = |
| { N0.getOperand(0), N0.getOperand(1), |
| DAG.getConstantFP(-1.0, VT) , DAG.getConstantFP(0.0, VT), |
| N0.getOperand(2) }; |
| return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); |
| } |
| |
| // fold (sint_to_fp (zext (setcc x, y, cc))) -> |
| // (select_cc x, y, 1.0, 0.0,, cc) |
| if (N0.getOpcode() == ISD::ZERO_EXTEND && |
| N0.getOperand(0).getOpcode() == ISD::SETCC &&!VT.isVector() && |
| (!LegalOperations || |
| TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { |
| SDValue Ops[] = |
| { N0.getOperand(0).getOperand(0), N0.getOperand(0).getOperand(1), |
| DAG.getConstantFP(1.0, VT) , DAG.getConstantFP(0.0, VT), |
| N0.getOperand(0).getOperand(2) }; |
| return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitUINT_TO_FP(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| EVT OpVT = N0.getValueType(); |
| |
| // fold (uint_to_fp c1) -> c1fp |
| if (N0C && |
| // ...but only if the target supports immediate floating-point values |
| (!LegalOperations || |
| TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) |
| return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0); |
| |
| // If the input is a legal type, and UINT_TO_FP is not legal on this target, |
| // but SINT_TO_FP is legal on this target, try to convert. |
| if (!TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT) && |
| TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT)) { |
| // If the sign bit is known to be zero, we can change this to SINT_TO_FP. |
| if (DAG.SignBitIsZero(N0)) |
| return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0); |
| } |
| |
| // The next optimizations are desireable only if SELECT_CC can be lowered. |
| // Check against MVT::Other for SELECT_CC, which is a workaround for targets |
| // having to say they don't support SELECT_CC on every type the DAG knows |
| // about, since there is no way to mark an opcode illegal at all value types |
| // (See also visitSELECT) |
| if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other)) { |
| // fold (uint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc) |
| |
| if (N0.getOpcode() == ISD::SETCC && !VT.isVector() && |
| (!LegalOperations || |
| TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { |
| SDValue Ops[] = |
| { N0.getOperand(0), N0.getOperand(1), |
| DAG.getConstantFP(1.0, VT), DAG.getConstantFP(0.0, VT), |
| N0.getOperand(2) }; |
| return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFP_TO_SINT(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (fp_to_sint c1fp) -> c1 |
| if (N0CFP) |
| return DAG.getNode(ISD::FP_TO_SINT, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFP_TO_UINT(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (fp_to_uint c1fp) -> c1 |
| if (N0CFP) |
| return DAG.getNode(ISD::FP_TO_UINT, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFP_ROUND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (fp_round c1fp) -> c1fp |
| if (N0CFP) |
| return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0, N1); |
| |
| // fold (fp_round (fp_extend x)) -> x |
| if (N0.getOpcode() == ISD::FP_EXTEND && VT == N0.getOperand(0).getValueType()) |
| return N0.getOperand(0); |
| |
| // fold (fp_round (fp_round x)) -> (fp_round x) |
| if (N0.getOpcode() == ISD::FP_ROUND) { |
| // This is a value preserving truncation if both round's are. |
| bool IsTrunc = N->getConstantOperandVal(1) == 1 && |
| N0.getNode()->getConstantOperandVal(1) == 1; |
| return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0.getOperand(0), |
| DAG.getIntPtrConstant(IsTrunc)); |
| } |
| |
| // fold (fp_round (copysign X, Y)) -> (copysign (fp_round X), Y) |
| if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse()) { |
| SDValue Tmp = DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(), VT, |
| N0.getOperand(0), N1); |
| AddToWorkList(Tmp.getNode()); |
| return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, |
| Tmp, N0.getOperand(1)); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFP_ROUND_INREG(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| EVT EVT = cast<VTSDNode>(N->getOperand(1))->getVT(); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| |
| // fold (fp_round_inreg c1fp) -> c1fp |
| if (N0CFP && isTypeLegal(EVT)) { |
| SDValue Round = DAG.getConstantFP(*N0CFP->getConstantFPValue(), EVT); |
| return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, Round); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFP_EXTEND(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // If this is fp_round(fpextend), don't fold it, allow ourselves to be folded. |
| if (N->hasOneUse() && |
| N->use_begin()->getOpcode() == ISD::FP_ROUND) |
| return SDValue(); |
| |
| // fold (fp_extend c1fp) -> c1fp |
| if (N0CFP) |
| return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, N0); |
| |
| // Turn fp_extend(fp_round(X, 1)) -> x since the fp_round doesn't affect the |
| // value of X. |
| if (N0.getOpcode() == ISD::FP_ROUND |
| && N0.getNode()->getConstantOperandVal(1) == 1) { |
| SDValue In = N0.getOperand(0); |
| if (In.getValueType() == VT) return In; |
| if (VT.bitsLT(In.getValueType())) |
| return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, |
| In, N0.getOperand(1)); |
| return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, In); |
| } |
| |
| // fold (fpext (load x)) -> (fpext (fptrunc (extload x))) |
| if (ISD::isNON_EXTLoad(N0.getNode()) && N0.hasOneUse() && |
| ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) || |
| TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) { |
| LoadSDNode *LN0 = cast<LoadSDNode>(N0); |
| SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT, |
| LN0->getChain(), |
| LN0->getBasePtr(), LN0->getPointerInfo(), |
| N0.getValueType(), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->getAlignment()); |
| CombineTo(N, ExtLoad); |
| CombineTo(N0.getNode(), |
| DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(), |
| N0.getValueType(), ExtLoad, DAG.getIntPtrConstant(1)), |
| ExtLoad.getValue(1)); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFNEG(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| EVT VT = N->getValueType(0); |
| |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVUnaryOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| if (isNegatibleForFree(N0, LegalOperations, DAG.getTargetLoweringInfo(), |
| &DAG.getTarget().Options)) |
| return GetNegatedExpression(N0, DAG, LegalOperations); |
| |
| // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading |
| // constant pool values. |
| if (!TLI.isFNegFree(VT) && N0.getOpcode() == ISD::BITCAST && |
| !VT.isVector() && |
| N0.getNode()->hasOneUse() && |
| N0.getOperand(0).getValueType().isInteger()) { |
| SDValue Int = N0.getOperand(0); |
| EVT IntVT = Int.getValueType(); |
| if (IntVT.isInteger() && !IntVT.isVector()) { |
| Int = DAG.getNode(ISD::XOR, N0.getDebugLoc(), IntVT, Int, |
| DAG.getConstant(APInt::getSignBit(IntVT.getSizeInBits()), IntVT)); |
| AddToWorkList(Int.getNode()); |
| return DAG.getNode(ISD::BITCAST, N->getDebugLoc(), |
| VT, Int); |
| } |
| } |
| |
| // (fneg (fmul c, x)) -> (fmul -c, x) |
| if (N0.getOpcode() == ISD::FMUL) { |
| ConstantFPSDNode *CFP1 = dyn_cast<ConstantFPSDNode>(N0.getOperand(1)); |
| if (CFP1) { |
| return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, |
| N0.getOperand(0), |
| DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, |
| N0.getOperand(1))); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFCEIL(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (fceil c1) -> fceil(c1) |
| if (N0CFP) |
| return DAG.getNode(ISD::FCEIL, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFTRUNC(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (ftrunc c1) -> ftrunc(c1) |
| if (N0CFP) |
| return DAG.getNode(ISD::FTRUNC, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFFLOOR(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| // fold (ffloor c1) -> ffloor(c1) |
| if (N0CFP) |
| return DAG.getNode(ISD::FFLOOR, N->getDebugLoc(), VT, N0); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitFABS(SDNode *N) { |
| SDValue N0 = N->getOperand(0); |
| ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0); |
| EVT VT = N->getValueType(0); |
| |
| if (VT.isVector()) { |
| SDValue FoldedVOp = SimplifyVUnaryOp(N); |
| if (FoldedVOp.getNode()) return FoldedVOp; |
| } |
| |
| // fold (fabs c1) -> fabs(c1) |
| if (N0CFP) |
| return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0); |
| // fold (fabs (fabs x)) -> (fabs x) |
| if (N0.getOpcode() == ISD::FABS) |
| return N->getOperand(0); |
| // fold (fabs (fneg x)) -> (fabs x) |
| // fold (fabs (fcopysign x, y)) -> (fabs x) |
| if (N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FCOPYSIGN) |
| return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0.getOperand(0)); |
| |
| // Transform fabs(bitconvert(x)) -> bitconvert(x&~sign) to avoid loading |
| // constant pool values. |
| if (!TLI.isFAbsFree(VT) && |
| N0.getOpcode() == ISD::BITCAST && N0.getNode()->hasOneUse() && |
| N0.getOperand(0).getValueType().isInteger() && |
| !N0.getOperand(0).getValueType().isVector()) { |
| SDValue Int = N0.getOperand(0); |
| EVT IntVT = Int.getValueType(); |
| if (IntVT.isInteger() && !IntVT.isVector()) { |
| Int = DAG.getNode(ISD::AND, N0.getDebugLoc(), IntVT, Int, |
| DAG.getConstant(~APInt::getSignBit(IntVT.getSizeInBits()), IntVT)); |
| AddToWorkList(Int.getNode()); |
| return DAG.getNode(ISD::BITCAST, N->getDebugLoc(), |
| N->getValueType(0), Int); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitBRCOND(SDNode *N) { |
| SDValue Chain = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| SDValue N2 = N->getOperand(2); |
| |
| // If N is a constant we could fold this into a fallthrough or unconditional |
| // branch. However that doesn't happen very often in normal code, because |
| // Instcombine/SimplifyCFG should have handled the available opportunities. |
| // If we did this folding here, it would be necessary to update the |
| // MachineBasicBlock CFG, which is awkward. |
| |
| // fold a brcond with a setcc condition into a BR_CC node if BR_CC is legal |
| // on the target. |
| if (N1.getOpcode() == ISD::SETCC && |
| TLI.isOperationLegalOrCustom(ISD::BR_CC, |
| N1.getOperand(0).getValueType())) { |
| return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other, |
| Chain, N1.getOperand(2), |
| N1.getOperand(0), N1.getOperand(1), N2); |
| } |
| |
| if ((N1.hasOneUse() && N1.getOpcode() == ISD::SRL) || |
| ((N1.getOpcode() == ISD::TRUNCATE && N1.hasOneUse()) && |
| (N1.getOperand(0).hasOneUse() && |
| N1.getOperand(0).getOpcode() == ISD::SRL))) { |
| SDNode *Trunc = 0; |
| if (N1.getOpcode() == ISD::TRUNCATE) { |
| // Look pass the truncate. |
| Trunc = N1.getNode(); |
| N1 = N1.getOperand(0); |
| } |
| |
| // Match this pattern so that we can generate simpler code: |
| // |
| // %a = ... |
| // %b = and i32 %a, 2 |
| // %c = srl i32 %b, 1 |
| // brcond i32 %c ... |
| // |
| // into |
| // |
| // %a = ... |
| // %b = and i32 %a, 2 |
| // %c = setcc eq %b, 0 |
| // brcond %c ... |
| // |
| // This applies only when the AND constant value has one bit set and the |
| // SRL constant is equal to the log2 of the AND constant. The back-end is |
| // smart enough to convert the result into a TEST/JMP sequence. |
| SDValue Op0 = N1.getOperand(0); |
| SDValue Op1 = N1.getOperand(1); |
| |
| if (Op0.getOpcode() == ISD::AND && |
| Op1.getOpcode() == ISD::Constant) { |
| SDValue AndOp1 = Op0.getOperand(1); |
| |
| if (AndOp1.getOpcode() == ISD::Constant) { |
| const APInt &AndConst = cast<ConstantSDNode>(AndOp1)->getAPIntValue(); |
| |
| if (AndConst.isPowerOf2() && |
| cast<ConstantSDNode>(Op1)->getAPIntValue()==AndConst.logBase2()) { |
| SDValue SetCC = |
| DAG.getSetCC(N->getDebugLoc(), |
| TLI.getSetCCResultType(Op0.getValueType()), |
| Op0, DAG.getConstant(0, Op0.getValueType()), |
| ISD::SETNE); |
| |
| SDValue NewBRCond = DAG.getNode(ISD::BRCOND, N->getDebugLoc(), |
| MVT::Other, Chain, SetCC, N2); |
| // Don't add the new BRCond into the worklist or else SimplifySelectCC |
| // will convert it back to (X & C1) >> C2. |
| CombineTo(N, NewBRCond, false); |
| // Truncate is dead. |
| if (Trunc) { |
| removeFromWorkList(Trunc); |
| DAG.DeleteNode(Trunc); |
| } |
| // Replace the uses of SRL with SETCC |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(N1, SetCC); |
| removeFromWorkList(N1.getNode()); |
| DAG.DeleteNode(N1.getNode()); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| |
| if (Trunc) |
| // Restore N1 if the above transformation doesn't match. |
| N1 = N->getOperand(1); |
| } |
| |
| // Transform br(xor(x, y)) -> br(x != y) |
| // Transform br(xor(xor(x,y), 1)) -> br (x == y) |
| if (N1.hasOneUse() && N1.getOpcode() == ISD::XOR) { |
| SDNode *TheXor = N1.getNode(); |
| SDValue Op0 = TheXor->getOperand(0); |
| SDValue Op1 = TheXor->getOperand(1); |
| if (Op0.getOpcode() == Op1.getOpcode()) { |
| // Avoid missing important xor optimizations. |
| SDValue Tmp = visitXOR(TheXor); |
| if (Tmp.getNode()) { |
| if (Tmp.getNode() != TheXor) { |
| DEBUG(dbgs() << "\nReplacing.8 "; |
| TheXor->dump(&DAG); |
| dbgs() << "\nWith: "; |
| Tmp.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(N1, Tmp); |
| removeFromWorkList(TheXor); |
| DAG.DeleteNode(TheXor); |
| return DAG.getNode(ISD::BRCOND, N->getDebugLoc(), |
| MVT::Other, Chain, Tmp, N2); |
| } |
| |
| // visitXOR has changed XOR's operands. |
| Op0 = TheXor->getOperand(0); |
| Op1 = TheXor->getOperand(1); |
| } |
| } |
| |
| if (Op0.getOpcode() != ISD::SETCC && Op1.getOpcode() != ISD::SETCC) { |
| bool Equal = false; |
| if (ConstantSDNode *RHSCI = dyn_cast<ConstantSDNode>(Op0)) |
| if (RHSCI->getAPIntValue() == 1 && Op0.hasOneUse() && |
| Op0.getOpcode() == ISD::XOR) { |
| TheXor = Op0.getNode(); |
| Equal = true; |
| } |
| |
| EVT SetCCVT = N1.getValueType(); |
| if (LegalTypes) |
| SetCCVT = TLI.getSetCCResultType(SetCCVT); |
| SDValue SetCC = DAG.getSetCC(TheXor->getDebugLoc(), |
| SetCCVT, |
| Op0, Op1, |
| Equal ? ISD::SETEQ : ISD::SETNE); |
| // Replace the uses of XOR with SETCC |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(N1, SetCC); |
| removeFromWorkList(N1.getNode()); |
| DAG.DeleteNode(N1.getNode()); |
| return DAG.getNode(ISD::BRCOND, N->getDebugLoc(), |
| MVT::Other, Chain, SetCC, N2); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| // Operand List for BR_CC: Chain, CondCC, CondLHS, CondRHS, DestBB. |
| // |
| SDValue DAGCombiner::visitBR_CC(SDNode *N) { |
| CondCodeSDNode *CC = cast<CondCodeSDNode>(N->getOperand(1)); |
| SDValue CondLHS = N->getOperand(2), CondRHS = N->getOperand(3); |
| |
| // If N is a constant we could fold this into a fallthrough or unconditional |
| // branch. However that doesn't happen very often in normal code, because |
| // Instcombine/SimplifyCFG should have handled the available opportunities. |
| // If we did this folding here, it would be necessary to update the |
| // MachineBasicBlock CFG, which is awkward. |
| |
| // Use SimplifySetCC to simplify SETCC's. |
| SDValue Simp = SimplifySetCC(TLI.getSetCCResultType(CondLHS.getValueType()), |
| CondLHS, CondRHS, CC->get(), N->getDebugLoc(), |
| false); |
| if (Simp.getNode()) AddToWorkList(Simp.getNode()); |
| |
| // fold to a simpler setcc |
| if (Simp.getNode() && Simp.getOpcode() == ISD::SETCC) |
| return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other, |
| N->getOperand(0), Simp.getOperand(2), |
| Simp.getOperand(0), Simp.getOperand(1), |
| N->getOperand(4)); |
| |
| return SDValue(); |
| } |
| |
| /// canFoldInAddressingMode - Return true if 'Use' is a load or a store that |
| /// uses N as its base pointer and that N may be folded in the load / store |
| /// addressing mode. |
| static bool canFoldInAddressingMode(SDNode *N, SDNode *Use, |
| SelectionDAG &DAG, |
| const TargetLowering &TLI) { |
| EVT VT; |
| if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Use)) { |
| if (LD->isIndexed() || LD->getBasePtr().getNode() != N) |
| return false; |
| VT = Use->getValueType(0); |
| } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(Use)) { |
| if (ST->isIndexed() || ST->getBasePtr().getNode() != N) |
| return false; |
| VT = ST->getValue().getValueType(); |
| } else |
| return false; |
| |
| TargetLowering::AddrMode AM; |
| if (N->getOpcode() == ISD::ADD) { |
| ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1)); |
| if (Offset) |
| // [reg +/- imm] |
| AM.BaseOffs = Offset->getSExtValue(); |
| else |
| // [reg +/- reg] |
| AM.Scale = 1; |
| } else if (N->getOpcode() == ISD::SUB) { |
| ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1)); |
| if (Offset) |
| // [reg +/- imm] |
| AM.BaseOffs = -Offset->getSExtValue(); |
| else |
| // [reg +/- reg] |
| AM.Scale = 1; |
| } else |
| return false; |
| |
| return TLI.isLegalAddressingMode(AM, VT.getTypeForEVT(*DAG.getContext())); |
| } |
| |
| /// CombineToPreIndexedLoadStore - Try turning a load / store into a |
| /// pre-indexed load / store when the base pointer is an add or subtract |
| /// and it has other uses besides the load / store. After the |
| /// transformation, the new indexed load / store has effectively folded |
| /// the add / subtract in and all of its other uses are redirected to the |
| /// new load / store. |
| bool DAGCombiner::CombineToPreIndexedLoadStore(SDNode *N) { |
| if (Level < AfterLegalizeDAG) |
| return false; |
| |
| bool isLoad = true; |
| SDValue Ptr; |
| EVT VT; |
| if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) { |
| if (LD->isIndexed()) |
| return false; |
| VT = LD->getMemoryVT(); |
| if (!TLI.isIndexedLoadLegal(ISD::PRE_INC, VT) && |
| !TLI.isIndexedLoadLegal(ISD::PRE_DEC, VT)) |
| return false; |
| Ptr = LD->getBasePtr(); |
| } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) { |
| if (ST->isIndexed()) |
| return false; |
| VT = ST->getMemoryVT(); |
| if (!TLI.isIndexedStoreLegal(ISD::PRE_INC, VT) && |
| !TLI.isIndexedStoreLegal(ISD::PRE_DEC, VT)) |
| return false; |
| Ptr = ST->getBasePtr(); |
| isLoad = false; |
| } else { |
| return false; |
| } |
| |
| // If the pointer is not an add/sub, or if it doesn't have multiple uses, bail |
| // out. There is no reason to make this a preinc/predec. |
| if ((Ptr.getOpcode() != ISD::ADD && Ptr.getOpcode() != ISD::SUB) || |
| Ptr.getNode()->hasOneUse()) |
| return false; |
| |
| // Ask the target to do addressing mode selection. |
| SDValue BasePtr; |
| SDValue Offset; |
| ISD::MemIndexedMode AM = ISD::UNINDEXED; |
| if (!TLI.getPreIndexedAddressParts(N, BasePtr, Offset, AM, DAG)) |
| return false; |
| |
| // Backends without true r+i pre-indexed forms may need to pass a |
| // constant base with a variable offset so that constant coercion |
| // will work with the patterns in canonical form. |
| bool Swapped = false; |
| if (isa<ConstantSDNode>(BasePtr)) { |
| std::swap(BasePtr, Offset); |
| Swapped = true; |
| } |
| |
| // Don't create a indexed load / store with zero offset. |
| if (isa<ConstantSDNode>(Offset) && |
| cast<ConstantSDNode>(Offset)->isNullValue()) |
| return false; |
| |
| // Try turning it into a pre-indexed load / store except when: |
| // 1) The new base ptr is a frame index. |
| // 2) If N is a store and the new base ptr is either the same as or is a |
| // predecessor of the value being stored. |
| // 3) Another use of old base ptr is a predecessor of N. If ptr is folded |
| // that would create a cycle. |
| // 4) All uses are load / store ops that use it as old base ptr. |
| |
| // Check #1. Preinc'ing a frame index would require copying the stack pointer |
| // (plus the implicit offset) to a register to preinc anyway. |
| if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr)) |
| return false; |
| |
| // Check #2. |
| if (!isLoad) { |
| SDValue Val = cast<StoreSDNode>(N)->getValue(); |
| if (Val == BasePtr || BasePtr.getNode()->isPredecessorOf(Val.getNode())) |
| return false; |
| } |
| |
| // If the offset is a constant, there may be other adds of constants that |
| // can be folded with this one. We should do this to avoid having to keep |
| // a copy of the original base pointer. |
| SmallVector<SDNode *, 16> OtherUses; |
| if (isa<ConstantSDNode>(Offset)) |
| for (SDNode::use_iterator I = BasePtr.getNode()->use_begin(), |
| E = BasePtr.getNode()->use_end(); I != E; ++I) { |
| SDNode *Use = *I; |
| if (Use == Ptr.getNode()) |
| continue; |
| |
| if (Use->isPredecessorOf(N)) |
| continue; |
| |
| if (Use->getOpcode() != ISD::ADD && Use->getOpcode() != ISD::SUB) { |
| OtherUses.clear(); |
| break; |
| } |
| |
| SDValue Op0 = Use->getOperand(0), Op1 = Use->getOperand(1); |
| if (Op1.getNode() == BasePtr.getNode()) |
| std::swap(Op0, Op1); |
| assert(Op0.getNode() == BasePtr.getNode() && |
| "Use of ADD/SUB but not an operand"); |
| |
| if (!isa<ConstantSDNode>(Op1)) { |
| OtherUses.clear(); |
| break; |
| } |
| |
| // FIXME: In some cases, we can be smarter about this. |
| if (Op1.getValueType() != Offset.getValueType()) { |
| OtherUses.clear(); |
| break; |
| } |
| |
| OtherUses.push_back(Use); |
| } |
| |
| if (Swapped) |
| std::swap(BasePtr, Offset); |
| |
| // Now check for #3 and #4. |
| bool RealUse = false; |
| |
| // Caches for hasPredecessorHelper |
| SmallPtrSet<const SDNode *, 32> Visited; |
| SmallVector<const SDNode *, 16> Worklist; |
| |
| for (SDNode::use_iterator I = Ptr.getNode()->use_begin(), |
| E = Ptr.getNode()->use_end(); I != E; ++I) { |
| SDNode *Use = *I; |
| if (Use == N) |
| continue; |
| if (N->hasPredecessorHelper(Use, Visited, Worklist)) |
| return false; |
| |
| // If Ptr may be folded in addressing mode of other use, then it's |
| // not profitable to do this transformation. |
| if (!canFoldInAddressingMode(Ptr.getNode(), Use, DAG, TLI)) |
| RealUse = true; |
| } |
| |
| if (!RealUse) |
| return false; |
| |
| SDValue Result; |
| if (isLoad) |
| Result = DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(), |
| BasePtr, Offset, AM); |
| else |
| Result = DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(), |
| BasePtr, Offset, AM); |
| ++PreIndexedNodes; |
| ++NodesCombined; |
| DEBUG(dbgs() << "\nReplacing.4 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith: "; |
| Result.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| WorkListRemover DeadNodes(*this); |
| if (isLoad) { |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0)); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2)); |
| } else { |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1)); |
| } |
| |
| // Finally, since the node is now dead, remove it from the graph. |
| DAG.DeleteNode(N); |
| |
| if (Swapped) |
| std::swap(BasePtr, Offset); |
| |
| // Replace other uses of BasePtr that can be updated to use Ptr |
| for (unsigned i = 0, e = OtherUses.size(); i != e; ++i) { |
| unsigned OffsetIdx = 1; |
| if (OtherUses[i]->getOperand(OffsetIdx).getNode() == BasePtr.getNode()) |
| OffsetIdx = 0; |
| assert(OtherUses[i]->getOperand(!OffsetIdx).getNode() == |
| BasePtr.getNode() && "Expected BasePtr operand"); |
| |
| APInt OV = |
| cast<ConstantSDNode>(Offset)->getAPIntValue(); |
| if (AM == ISD::PRE_DEC) |
| OV = -OV; |
| |
| ConstantSDNode *CN = |
| cast<ConstantSDNode>(OtherUses[i]->getOperand(OffsetIdx)); |
| APInt CNV = CN->getAPIntValue(); |
| if (OtherUses[i]->getOpcode() == ISD::SUB && OffsetIdx == 1) |
| CNV += OV; |
| else |
| CNV -= OV; |
| |
| SDValue NewOp1 = Result.getValue(isLoad ? 1 : 0); |
| SDValue NewOp2 = DAG.getConstant(CNV, CN->getValueType(0)); |
| if (OffsetIdx == 0) |
| std::swap(NewOp1, NewOp2); |
| |
| SDValue NewUse = DAG.getNode(OtherUses[i]->getOpcode(), |
| OtherUses[i]->getDebugLoc(), |
| OtherUses[i]->getValueType(0), NewOp1, NewOp2); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(OtherUses[i], 0), NewUse); |
| removeFromWorkList(OtherUses[i]); |
| DAG.DeleteNode(OtherUses[i]); |
| } |
| |
| // Replace the uses of Ptr with uses of the updated base value. |
| DAG.ReplaceAllUsesOfValueWith(Ptr, Result.getValue(isLoad ? 1 : 0)); |
| removeFromWorkList(Ptr.getNode()); |
| DAG.DeleteNode(Ptr.getNode()); |
| |
| return true; |
| } |
| |
| /// CombineToPostIndexedLoadStore - Try to combine a load / store with a |
| /// add / sub of the base pointer node into a post-indexed load / store. |
| /// The transformation folded the add / subtract into the new indexed |
| /// load / store effectively and all of its uses are redirected to the |
| /// new load / store. |
| bool DAGCombiner::CombineToPostIndexedLoadStore(SDNode *N) { |
| if (Level < AfterLegalizeDAG) |
| return false; |
| |
| bool isLoad = true; |
| SDValue Ptr; |
| EVT VT; |
| if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) { |
| if (LD->isIndexed()) |
| return false; |
| VT = LD->getMemoryVT(); |
| if (!TLI.isIndexedLoadLegal(ISD::POST_INC, VT) && |
| !TLI.isIndexedLoadLegal(ISD::POST_DEC, VT)) |
| return false; |
| Ptr = LD->getBasePtr(); |
| } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) { |
| if (ST->isIndexed()) |
| return false; |
| VT = ST->getMemoryVT(); |
| if (!TLI.isIndexedStoreLegal(ISD::POST_INC, VT) && |
| !TLI.isIndexedStoreLegal(ISD::POST_DEC, VT)) |
| return false; |
| Ptr = ST->getBasePtr(); |
| isLoad = false; |
| } else { |
| return false; |
| } |
| |
| if (Ptr.getNode()->hasOneUse()) |
| return false; |
| |
| for (SDNode::use_iterator I = Ptr.getNode()->use_begin(), |
| E = Ptr.getNode()->use_end(); I != E; ++I) { |
| SDNode *Op = *I; |
| if (Op == N || |
| (Op->getOpcode() != ISD::ADD && Op->getOpcode() != ISD::SUB)) |
| continue; |
| |
| SDValue BasePtr; |
| SDValue Offset; |
| ISD::MemIndexedMode AM = ISD::UNINDEXED; |
| if (TLI.getPostIndexedAddressParts(N, Op, BasePtr, Offset, AM, DAG)) { |
| // Don't create a indexed load / store with zero offset. |
| if (isa<ConstantSDNode>(Offset) && |
| cast<ConstantSDNode>(Offset)->isNullValue()) |
| continue; |
| |
| // Try turning it into a post-indexed load / store except when |
| // 1) All uses are load / store ops that use it as base ptr (and |
| // it may be folded as addressing mmode). |
| // 2) Op must be independent of N, i.e. Op is neither a predecessor |
| // nor a successor of N. Otherwise, if Op is folded that would |
| // create a cycle. |
| |
| if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr)) |
| continue; |
| |
| // Check for #1. |
| bool TryNext = false; |
| for (SDNode::use_iterator II = BasePtr.getNode()->use_begin(), |
| EE = BasePtr.getNode()->use_end(); II != EE; ++II) { |
| SDNode *Use = *II; |
| if (Use == Ptr.getNode()) |
| continue; |
| |
| // If all the uses are load / store addresses, then don't do the |
| // transformation. |
| if (Use->getOpcode() == ISD::ADD || Use->getOpcode() == ISD::SUB){ |
| bool RealUse = false; |
| for (SDNode::use_iterator III = Use->use_begin(), |
| EEE = Use->use_end(); III != EEE; ++III) { |
| SDNode *UseUse = *III; |
| if (!canFoldInAddressingMode(Use, UseUse, DAG, TLI)) |
| RealUse = true; |
| } |
| |
| if (!RealUse) { |
| TryNext = true; |
| break; |
| } |
| } |
| } |
| |
| if (TryNext) |
| continue; |
| |
| // Check for #2 |
| if (!Op->isPredecessorOf(N) && !N->isPredecessorOf(Op)) { |
| SDValue Result = isLoad |
| ? DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(), |
| BasePtr, Offset, AM) |
| : DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(), |
| BasePtr, Offset, AM); |
| ++PostIndexedNodes; |
| ++NodesCombined; |
| DEBUG(dbgs() << "\nReplacing.5 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith: "; |
| Result.getNode()->dump(&DAG); |
| dbgs() << '\n'); |
| WorkListRemover DeadNodes(*this); |
| if (isLoad) { |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0)); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2)); |
| } else { |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1)); |
| } |
| |
| // Finally, since the node is now dead, remove it from the graph. |
| DAG.DeleteNode(N); |
| |
| // Replace the uses of Use with uses of the updated base value. |
| DAG.ReplaceAllUsesOfValueWith(SDValue(Op, 0), |
| Result.getValue(isLoad ? 1 : 0)); |
| removeFromWorkList(Op); |
| DAG.DeleteNode(Op); |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| SDValue DAGCombiner::visitLOAD(SDNode *N) { |
| LoadSDNode *LD = cast<LoadSDNode>(N); |
| SDValue Chain = LD->getChain(); |
| SDValue Ptr = LD->getBasePtr(); |
| |
| // If load is not volatile and there are no uses of the loaded value (and |
| // the updated indexed value in case of indexed loads), change uses of the |
| // chain value into uses of the chain input (i.e. delete the dead load). |
| if (!LD->isVolatile()) { |
| if (N->getValueType(1) == MVT::Other) { |
| // Unindexed loads. |
| if (!N->hasAnyUseOfValue(0)) { |
| // It's not safe to use the two value CombineTo variant here. e.g. |
| // v1, chain2 = load chain1, loc |
| // v2, chain3 = load chain2, loc |
| // v3 = add v2, c |
| // Now we replace use of chain2 with chain1. This makes the second load |
| // isomorphic to the one we are deleting, and thus makes this load live. |
| DEBUG(dbgs() << "\nReplacing.6 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith chain: "; |
| Chain.getNode()->dump(&DAG); |
| dbgs() << "\n"); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Chain); |
| |
| if (N->use_empty()) { |
| removeFromWorkList(N); |
| DAG.DeleteNode(N); |
| } |
| |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } else { |
| // Indexed loads. |
| assert(N->getValueType(2) == MVT::Other && "Malformed indexed loads?"); |
| if (!N->hasAnyUseOfValue(0) && !N->hasAnyUseOfValue(1)) { |
| SDValue Undef = DAG.getUNDEF(N->getValueType(0)); |
| DEBUG(dbgs() << "\nReplacing.7 "; |
| N->dump(&DAG); |
| dbgs() << "\nWith: "; |
| Undef.getNode()->dump(&DAG); |
| dbgs() << " and 2 other values\n"); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Undef); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), |
| DAG.getUNDEF(N->getValueType(1))); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(N, 2), Chain); |
| removeFromWorkList(N); |
| DAG.DeleteNode(N); |
| return SDValue(N, 0); // Return N so it doesn't get rechecked! |
| } |
| } |
| } |
| |
| // If this load is directly stored, replace the load value with the stored |
| // value. |
| // TODO: Handle store large -> read small portion. |
| // TODO: Handle TRUNCSTORE/LOADEXT |
| if (ISD::isNormalLoad(N) && !LD->isVolatile()) { |
| if (ISD::isNON_TRUNCStore(Chain.getNode())) { |
| StoreSDNode *PrevST = cast<StoreSDNode>(Chain); |
| if (PrevST->getBasePtr() == Ptr && |
| PrevST->getValue().getValueType() == N->getValueType(0)) |
| return CombineTo(N, Chain.getOperand(1), Chain); |
| } |
| } |
| |
| // Try to infer better alignment information than the load already has. |
| if (OptLevel != CodeGenOpt::None && LD->isUnindexed()) { |
| if (unsigned Align = DAG.InferPtrAlignment(Ptr)) { |
| if (Align > LD->getMemOperand()->getBaseAlignment()) { |
| SDValue NewLoad = |
| DAG.getExtLoad(LD->getExtensionType(), N->getDebugLoc(), |
| LD->getValueType(0), |
| Chain, Ptr, LD->getPointerInfo(), |
| LD->getMemoryVT(), |
| LD->isVolatile(), LD->isNonTemporal(), Align); |
| return CombineTo(N, NewLoad, SDValue(NewLoad.getNode(), 1), true); |
| } |
| } |
| } |
| |
| if (CombinerAA) { |
| // Walk up chain skipping non-aliasing memory nodes. |
| SDValue BetterChain = FindBetterChain(N, Chain); |
| |
| // If there is a better chain. |
| if (Chain != BetterChain) { |
| SDValue ReplLoad; |
| |
| // Replace the chain to void dependency. |
| if (LD->getExtensionType() == ISD::NON_EXTLOAD) { |
| ReplLoad = DAG.getLoad(N->getValueType(0), LD->getDebugLoc(), |
| BetterChain, Ptr, LD->getPointerInfo(), |
| LD->isVolatile(), LD->isNonTemporal(), |
| LD->isInvariant(), LD->getAlignment()); |
| } else { |
| ReplLoad = DAG.getExtLoad(LD->getExtensionType(), LD->getDebugLoc(), |
| LD->getValueType(0), |
| BetterChain, Ptr, LD->getPointerInfo(), |
| LD->getMemoryVT(), |
| LD->isVolatile(), |
| LD->isNonTemporal(), |
| LD->getAlignment()); |
| } |
| |
| // Create token factor to keep old chain connected. |
| SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), |
| MVT::Other, Chain, ReplLoad.getValue(1)); |
| |
| // Make sure the new and old chains are cleaned up. |
| AddToWorkList(Token.getNode()); |
| |
| // Replace uses with load result and token factor. Don't add users |
| // to work list. |
| return CombineTo(N, ReplLoad.getValue(0), Token, false); |
| } |
| } |
| |
| // Try transforming N to an indexed load. |
| if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N)) |
| return SDValue(N, 0); |
| |
| return SDValue(); |
| } |
| |
| /// CheckForMaskedLoad - Check to see if V is (and load (ptr), imm), where the |
| /// load is having specific bytes cleared out. If so, return the byte size |
| /// being masked out and the shift amount. |
| static std::pair<unsigned, unsigned> |
| CheckForMaskedLoad(SDValue V, SDValue Ptr, SDValue Chain) { |
| std::pair<unsigned, unsigned> Result(0, 0); |
| |
| // Check for the structure we're looking for. |
| if (V->getOpcode() != ISD::AND || |
| !isa<ConstantSDNode>(V->getOperand(1)) || |
| !ISD::isNormalLoad(V->getOperand(0).getNode())) |
| return Result; |
| |
| // Check the chain and pointer. |
| LoadSDNode *LD = cast<LoadSDNode>(V->getOperand(0)); |
| if (LD->getBasePtr() != Ptr) return Result; // Not from same pointer. |
| |
| // The store should be chained directly to the load or be an operand of a |
| // tokenfactor. |
| if (LD == Chain.getNode()) |
| ; // ok. |
| else if (Chain->getOpcode() != ISD::TokenFactor) |
| return Result; // Fail. |
| else { |
| bool isOk = false; |
| for (unsigned i = 0, e = Chain->getNumOperands(); i != e; ++i) |
| if (Chain->getOperand(i).getNode() == LD) { |
| isOk = true; |
| break; |
| } |
| if (!isOk) return Result; |
| } |
| |
| // This only handles simple types. |
| if (V.getValueType() != MVT::i16 && |
| V.getValueType() != MVT::i32 && |
| V.getValueType() != MVT::i64) |
| return Result; |
| |
| // Check the constant mask. Invert it so that the bits being masked out are |
| // 0 and the bits being kept are 1. Use getSExtValue so that leading bits |
| // follow the sign bit for uniformity. |
| uint64_t NotMask = ~cast<ConstantSDNode>(V->getOperand(1))->getSExtValue(); |
| unsigned NotMaskLZ = CountLeadingZeros_64(NotMask); |
| if (NotMaskLZ & 7) return Result; // Must be multiple of a byte. |
| unsigned NotMaskTZ = CountTrailingZeros_64(NotMask); |
| if (NotMaskTZ & 7) return Result; // Must be multiple of a byte. |
| if (NotMaskLZ == 64) return Result; // All zero mask. |
| |
| // See if we have a continuous run of bits. If so, we have 0*1+0* |
| if (CountTrailingOnes_64(NotMask >> NotMaskTZ)+NotMaskTZ+NotMaskLZ != 64) |
| return Result; |
| |
| // Adjust NotMaskLZ down to be from the actual size of the int instead of i64. |
| if (V.getValueType() != MVT::i64 && NotMaskLZ) |
| NotMaskLZ -= 64-V.getValueSizeInBits(); |
| |
| unsigned MaskedBytes = (V.getValueSizeInBits()-NotMaskLZ-NotMaskTZ)/8; |
| switch (MaskedBytes) { |
| case 1: |
| case 2: |
| case 4: break; |
| default: return Result; // All one mask, or 5-byte mask. |
| } |
| |
| // Verify that the first bit starts at a multiple of mask so that the access |
| // is aligned the same as the access width. |
| if (NotMaskTZ && NotMaskTZ/8 % MaskedBytes) return Result; |
| |
| Result.first = MaskedBytes; |
| Result.second = NotMaskTZ/8; |
| return Result; |
| } |
| |
| |
| /// ShrinkLoadReplaceStoreWithStore - Check to see if IVal is something that |
| /// provides a value as specified by MaskInfo. If so, replace the specified |
| /// store with a narrower store of truncated IVal. |
| static SDNode * |
| ShrinkLoadReplaceStoreWithStore(const std::pair<unsigned, unsigned> &MaskInfo, |
| SDValue IVal, StoreSDNode *St, |
| DAGCombiner *DC) { |
| unsigned NumBytes = MaskInfo.first; |
| unsigned ByteShift = MaskInfo.second; |
| SelectionDAG &DAG = DC->getDAG(); |
| |
| // Check to see if IVal is all zeros in the part being masked in by the 'or' |
| // that uses this. If not, this is not a replacement. |
| APInt Mask = ~APInt::getBitsSet(IVal.getValueSizeInBits(), |
| ByteShift*8, (ByteShift+NumBytes)*8); |
| if (!DAG.MaskedValueIsZero(IVal, Mask)) return 0; |
| |
| // Check that it is legal on the target to do this. It is legal if the new |
| // VT we're shrinking to (i8/i16/i32) is legal or we're still before type |
| // legalization. |
| MVT VT = MVT::getIntegerVT(NumBytes*8); |
| if (!DC->isTypeLegal(VT)) |
| return 0; |
| |
| // Okay, we can do this! Replace the 'St' store with a store of IVal that is |
| // shifted by ByteShift and truncated down to NumBytes. |
| if (ByteShift) |
| IVal = DAG.getNode(ISD::SRL, IVal->getDebugLoc(), IVal.getValueType(), IVal, |
| DAG.getConstant(ByteShift*8, |
| DC->getShiftAmountTy(IVal.getValueType()))); |
| |
| // Figure out the offset for the store and the alignment of the access. |
| unsigned StOffset; |
| unsigned NewAlign = St->getAlignment(); |
| |
| if (DAG.getTargetLoweringInfo().isLittleEndian()) |
| StOffset = ByteShift; |
| else |
| StOffset = IVal.getValueType().getStoreSize() - ByteShift - NumBytes; |
| |
| SDValue Ptr = St->getBasePtr(); |
| if (StOffset) { |
| Ptr = DAG.getNode(ISD::ADD, IVal->getDebugLoc(), Ptr.getValueType(), |
| Ptr, DAG.getConstant(StOffset, Ptr.getValueType())); |
| NewAlign = MinAlign(NewAlign, StOffset); |
| } |
| |
| // Truncate down to the new size. |
| IVal = DAG.getNode(ISD::TRUNCATE, IVal->getDebugLoc(), VT, IVal); |
| |
| ++OpsNarrowed; |
| return DAG.getStore(St->getChain(), St->getDebugLoc(), IVal, Ptr, |
| St->getPointerInfo().getWithOffset(StOffset), |
| false, false, NewAlign).getNode(); |
| } |
| |
| |
| /// ReduceLoadOpStoreWidth - Look for sequence of load / op / store where op is |
| /// one of 'or', 'xor', and 'and' of immediates. If 'op' is only touching some |
| /// of the loaded bits, try narrowing the load and store if it would end up |
| /// being a win for performance or code size. |
| SDValue DAGCombiner::ReduceLoadOpStoreWidth(SDNode *N) { |
| StoreSDNode *ST = cast<StoreSDNode>(N); |
| if (ST->isVolatile()) |
| return SDValue(); |
| |
| SDValue Chain = ST->getChain(); |
| SDValue Value = ST->getValue(); |
| SDValue Ptr = ST->getBasePtr(); |
| EVT VT = Value.getValueType(); |
| |
| if (ST->isTruncatingStore() || VT.isVector() || !Value.hasOneUse()) |
| return SDValue(); |
| |
| unsigned Opc = Value.getOpcode(); |
| |
| // If this is "store (or X, Y), P" and X is "(and (load P), cst)", where cst |
| // is a byte mask indicating a consecutive number of bytes, check to see if |
| // Y is known to provide just those bytes. If so, we try to replace the |
| // load + replace + store sequence with a single (narrower) store, which makes |
| // the load dead. |
| if (Opc == ISD::OR) { |
| std::pair<unsigned, unsigned> MaskedLoad; |
| MaskedLoad = CheckForMaskedLoad(Value.getOperand(0), Ptr, Chain); |
| if (MaskedLoad.first) |
| if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad, |
| Value.getOperand(1), ST,this)) |
| return SDValue(NewST, 0); |
| |
| // Or is commutative, so try swapping X and Y. |
| MaskedLoad = CheckForMaskedLoad(Value.getOperand(1), Ptr, Chain); |
| if (MaskedLoad.first) |
| if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad, |
| Value.getOperand(0), ST,this)) |
| return SDValue(NewST, 0); |
| } |
| |
| if ((Opc != ISD::OR && Opc != ISD::XOR && Opc != ISD::AND) || |
| Value.getOperand(1).getOpcode() != ISD::Constant) |
| return SDValue(); |
| |
| SDValue N0 = Value.getOperand(0); |
| if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() && |
| Chain == SDValue(N0.getNode(), 1)) { |
| LoadSDNode *LD = cast<LoadSDNode>(N0); |
| if (LD->getBasePtr() != Ptr || |
| LD->getPointerInfo().getAddrSpace() != |
| ST->getPointerInfo().getAddrSpace()) |
| return SDValue(); |
| |
| // Find the type to narrow it the load / op / store to. |
| SDValue N1 = Value.getOperand(1); |
| unsigned BitWidth = N1.getValueSizeInBits(); |
| APInt Imm = cast<ConstantSDNode>(N1)->getAPIntValue(); |
| if (Opc == ISD::AND) |
| Imm ^= APInt::getAllOnesValue(BitWidth); |
| if (Imm == 0 || Imm.isAllOnesValue()) |
| return SDValue(); |
| unsigned ShAmt = Imm.countTrailingZeros(); |
| unsigned MSB = BitWidth - Imm.countLeadingZeros() - 1; |
| unsigned NewBW = NextPowerOf2(MSB - ShAmt); |
| EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW); |
| while (NewBW < BitWidth && |
| !(TLI.isOperationLegalOrCustom(Opc, NewVT) && |
| TLI.isNarrowingProfitable(VT, NewVT))) { |
| NewBW = NextPowerOf2(NewBW); |
| NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW); |
| } |
| if (NewBW >= BitWidth) |
| return SDValue(); |
| |
| // If the lsb changed does not start at the type bitwidth boundary, |
| // start at the previous one. |
| if (ShAmt % NewBW) |
| ShAmt = (((ShAmt + NewBW - 1) / NewBW) * NewBW) - NewBW; |
| APInt Mask = APInt::getBitsSet(BitWidth, ShAmt, |
| std::min(BitWidth, ShAmt + NewBW)); |
| if ((Imm & Mask) == Imm) { |
| APInt NewImm = (Imm & Mask).lshr(ShAmt).trunc(NewBW); |
| if (Opc == ISD::AND) |
| NewImm ^= APInt::getAllOnesValue(NewBW); |
| uint64_t PtrOff = ShAmt / 8; |
| // For big endian targets, we need to adjust the offset to the pointer to |
| // load the correct bytes. |
| if (TLI.isBigEndian()) |
| PtrOff = (BitWidth + 7 - NewBW) / 8 - PtrOff; |
| |
| unsigned NewAlign = MinAlign(LD->getAlignment(), PtrOff); |
| Type *NewVTTy = NewVT.getTypeForEVT(*DAG.getContext()); |
| if (NewAlign < TLI.getDataLayout()->getABITypeAlignment(NewVTTy)) |
| return SDValue(); |
| |
| SDValue NewPtr = DAG.getNode(ISD::ADD, LD->getDebugLoc(), |
| Ptr.getValueType(), Ptr, |
| DAG.getConstant(PtrOff, Ptr.getValueType())); |
| SDValue NewLD = DAG.getLoad(NewVT, N0.getDebugLoc(), |
| LD->getChain(), NewPtr, |
| LD->getPointerInfo().getWithOffset(PtrOff), |
| LD->isVolatile(), LD->isNonTemporal(), |
| LD->isInvariant(), NewAlign); |
| SDValue NewVal = DAG.getNode(Opc, Value.getDebugLoc(), NewVT, NewLD, |
| DAG.getConstant(NewImm, NewVT)); |
| SDValue NewST = DAG.getStore(Chain, N->getDebugLoc(), |
| NewVal, NewPtr, |
| ST->getPointerInfo().getWithOffset(PtrOff), |
| false, false, NewAlign); |
| |
| AddToWorkList(NewPtr.getNode()); |
| AddToWorkList(NewLD.getNode()); |
| AddToWorkList(NewVal.getNode()); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), NewLD.getValue(1)); |
| ++OpsNarrowed; |
| return NewST; |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| /// TransformFPLoadStorePair - For a given floating point load / store pair, |
| /// if the load value isn't used by any other operations, then consider |
| /// transforming the pair to integer load / store operations if the target |
| /// deems the transformation profitable. |
| SDValue DAGCombiner::TransformFPLoadStorePair(SDNode *N) { |
| StoreSDNode *ST = cast<StoreSDNode>(N); |
| SDValue Chain = ST->getChain(); |
| SDValue Value = ST->getValue(); |
| if (ISD::isNormalStore(ST) && ISD::isNormalLoad(Value.getNode()) && |
| Value.hasOneUse() && |
| Chain == SDValue(Value.getNode(), 1)) { |
| LoadSDNode *LD = cast<LoadSDNode>(Value); |
| EVT VT = LD->getMemoryVT(); |
| if (!VT.isFloatingPoint() || |
| VT != ST->getMemoryVT() || |
| LD->isNonTemporal() || |
| ST->isNonTemporal() || |
| LD->getPointerInfo().getAddrSpace() != 0 || |
| ST->getPointerInfo().getAddrSpace() != 0) |
| return SDValue(); |
| |
| EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits()); |
| if (!TLI.isOperationLegal(ISD::LOAD, IntVT) || |
| !TLI.isOperationLegal(ISD::STORE, IntVT) || |
| !TLI.isDesirableToTransformToIntegerOp(ISD::LOAD, VT) || |
| !TLI.isDesirableToTransformToIntegerOp(ISD::STORE, VT)) |
| return SDValue(); |
| |
| unsigned LDAlign = LD->getAlignment(); |
| unsigned STAlign = ST->getAlignment(); |
| Type *IntVTTy = IntVT.getTypeForEVT(*DAG.getContext()); |
| unsigned ABIAlign = TLI.getDataLayout()->getABITypeAlignment(IntVTTy); |
| if (LDAlign < ABIAlign || STAlign < ABIAlign) |
| return SDValue(); |
| |
| SDValue NewLD = DAG.getLoad(IntVT, Value.getDebugLoc(), |
| LD->getChain(), LD->getBasePtr(), |
| LD->getPointerInfo(), |
| false, false, false, LDAlign); |
| |
| SDValue NewST = DAG.getStore(NewLD.getValue(1), N->getDebugLoc(), |
| NewLD, ST->getBasePtr(), |
| ST->getPointerInfo(), |
| false, false, STAlign); |
| |
| AddToWorkList(NewLD.getNode()); |
| AddToWorkList(NewST.getNode()); |
| WorkListRemover DeadNodes(*this); |
| DAG.ReplaceAllUsesOfValueWith(Value.getValue(1), NewLD.getValue(1)); |
| ++LdStFP2Int; |
| return NewST; |
| } |
| |
| return SDValue(); |
| } |
| |
| /// Returns the base pointer and an integer offset from that object. |
| static std::pair<SDValue, int64_t> GetPointerBaseAndOffset(SDValue Ptr) { |
| if (Ptr->getOpcode() == ISD::ADD && isa<ConstantSDNode>(Ptr->getOperand(1))) { |
| int64_t Offset = cast<ConstantSDNode>(Ptr->getOperand(1))->getSExtValue(); |
| SDValue Base = Ptr->getOperand(0); |
| return std::make_pair(Base, Offset); |
| } |
| |
| return std::make_pair(Ptr, 0); |
| } |
| |
| /// Holds a pointer to an LSBaseSDNode as well as information on where it |
| /// is located in a sequence of memory operations connected by a chain. |
| struct MemOpLink { |
| MemOpLink (LSBaseSDNode *N, int64_t Offset, unsigned Seq): |
| MemNode(N), OffsetFromBase(Offset), SequenceNum(Seq) { } |
| // Ptr to the mem node. |
| LSBaseSDNode *MemNode; |
| // Offset from the base ptr. |
| int64_t OffsetFromBase; |
| // What is the sequence number of this mem node. |
| // Lowest mem operand in the DAG starts at zero. |
| unsigned SequenceNum; |
| }; |
| |
| /// Sorts store nodes in a link according to their offset from a shared |
| // base ptr. |
| struct ConsecutiveMemoryChainSorter { |
| bool operator()(MemOpLink LHS, MemOpLink RHS) { |
| return LHS.OffsetFromBase < RHS.OffsetFromBase; |
| } |
| }; |
| |
| bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) { |
| EVT MemVT = St->getMemoryVT(); |
| int64_t ElementSizeBytes = MemVT.getSizeInBits()/8; |
| bool NoVectors = DAG.getMachineFunction().getFunction()->getAttributes(). |
| hasAttribute(AttributeSet::FunctionIndex, Attribute::NoImplicitFloat); |
| |
| // Don't merge vectors into wider inputs. |
| if (MemVT.isVector() || !MemVT.isSimple()) |
| return false; |
| |
| // Perform an early exit check. Do not bother looking at stored values that |
| // are not constants or loads. |
| SDValue StoredVal = St->getValue(); |
| bool IsLoadSrc = isa<LoadSDNode>(StoredVal); |
| if (!isa<ConstantSDNode>(StoredVal) && !isa<ConstantFPSDNode>(StoredVal) && |
| !IsLoadSrc) |
| return false; |
| |
| // Only look at ends of store sequences. |
| SDValue Chain = SDValue(St, 1); |
| if (Chain->hasOneUse() && Chain->use_begin()->getOpcode() == ISD::STORE) |
| return false; |
| |
| // This holds the base pointer and the offset in bytes from the base pointer. |
| std::pair<SDValue, int64_t> BasePtr = |
| GetPointerBaseAndOffset(St->getBasePtr()); |
| |
| // We must have a base and an offset. |
| if (!BasePtr.first.getNode()) |
| return false; |
| |
| // Do not handle stores to undef base pointers. |
| if (BasePtr.first.getOpcode() == ISD::UNDEF) |
| return false; |
| |
| // Save the LoadSDNodes that we find in the chain. |
| // We need to make sure that these nodes do not interfere with |
| // any of the store nodes. |
| SmallVector<LSBaseSDNode*, 8> AliasLoadNodes; |
| |
| // Save the StoreSDNodes that we find in the chain. |
| SmallVector<MemOpLink, 8> StoreNodes; |
| |
| // Walk up the chain and look for nodes with offsets from the same |
| // base pointer. Stop when reaching an instruction with a different kind |
| // or instruction which has a different base pointer. |
| unsigned Seq = 0; |
| StoreSDNode *Index = St; |
| while (Index) { |
| // If the chain has more than one use, then we can't reorder the mem ops. |
| if (Index != St && !SDValue(Index, 1)->hasOneUse()) |
| break; |
| |
| // Find the base pointer and offset for this memory node. |
| std::pair<SDValue, int64_t> Ptr = |
| GetPointerBaseAndOffset(Index->getBasePtr()); |
| |
| // Check that the base pointer is the same as the original one. |
| if (Ptr.first.getNode() != BasePtr.first.getNode()) |
| break; |
| |
| // Check that the alignment is the same. |
| if (Index->getAlignment() != St->getAlignment()) |
| break; |
| |
| // The memory operands must not be volatile. |
| if (Index->isVolatile() || Index->isIndexed()) |
| break; |
| |
| // No truncation. |
| if (StoreSDNode *St = dyn_cast<StoreSDNode>(Index)) |
| if (St->isTruncatingStore()) |
| break; |
| |
| // The stored memory type must be the same. |
| if (Index->getMemoryVT() != MemVT) |
| break; |
| |
| // We do not allow unaligned stores because we want to prevent overriding |
| // stores. |
| if (Index->getAlignment()*8 != MemVT.getSizeInBits()) |
| break; |
| |
| // We found a potential memory operand to merge. |
| StoreNodes.push_back(MemOpLink(Index, Ptr.second, Seq++)); |
| |
| // Find the next memory operand in the chain. If the next operand in the |
| // chain is a store then move up and continue the scan with the next |
| // memory operand. If the next operand is a load save it and use alias |
| // information to check if it interferes with anything. |
| SDNode *NextInChain = Index->getChain().getNode(); |
| while (1) { |
| if (StoreSDNode *STn = dyn_cast<StoreSDNode>(NextInChain)) { |
| // We found a store node. Use it for the next iteration. |
| Index = STn; |
| break; |
| } else if (LoadSDNode *Ldn = dyn_cast<LoadSDNode>(NextInChain)) { |
| // Save the load node for later. Continue the scan. |
| AliasLoadNodes.push_back(Ldn); |
| NextInChain = Ldn->getChain().getNode(); |
| continue; |
| } else { |
| Index = NULL; |
| break; |
| } |
| } |
| } |
| |
| // Check if there is anything to merge. |
| if (StoreNodes.size() < 2) |
| return false; |
| |
| // Sort the memory operands according to their distance from the base pointer. |
| std::sort(StoreNodes.begin(), StoreNodes.end(), |
| ConsecutiveMemoryChainSorter()); |
| |
| // Scan the memory operations on the chain and find the first non-consecutive |
| // store memory address. |
| unsigned LastConsecutiveStore = 0; |
| int64_t StartAddress = StoreNodes[0].OffsetFromBase; |
| for (unsigned i = 0, e = StoreNodes.size(); i < e; ++i) { |
| |
| // Check that the addresses are consecutive starting from the second |
| // element in the list of stores. |
| if (i > 0) { |
| int64_t CurrAddress = StoreNodes[i].OffsetFromBase; |
| if (CurrAddress - StartAddress != (ElementSizeBytes * i)) |
| break; |
| } |
| |
| bool Alias = false; |
| // Check if this store interferes with any of the loads that we found. |
| for (unsigned ld = 0, lde = AliasLoadNodes.size(); ld < lde; ++ld) |
| if (isAlias(AliasLoadNodes[ld], StoreNodes[i].MemNode)) { |
| Alias = true; |
| break; |
| } |
| // We found a load that alias with this store. Stop the sequence. |
| if (Alias) |
| break; |
| |
| // Mark this node as useful. |
| LastConsecutiveStore = i; |
| } |
| |
| // The node with the lowest store address. |
| LSBaseSDNode *FirstInChain = StoreNodes[0].MemNode; |
| |
| // Store the constants into memory as one consecutive store. |
| if (!IsLoadSrc) { |
| unsigned LastLegalType = 0; |
| unsigned LastLegalVectorType = 0; |
| bool NonZero = false; |
| for (unsigned i=0; i<LastConsecutiveStore+1; ++i) { |
| StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode); |
| SDValue StoredVal = St->getValue(); |
| |
| if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(StoredVal)) { |
| NonZero |= !C->isNullValue(); |
| } else if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(StoredVal)) { |
| NonZero |= !C->getConstantFPValue()->isNullValue(); |
| } else { |
| // Non constant. |
| break; |
| } |
| |
| // Find a legal type for the constant store. |
| unsigned StoreBW = (i+1) * ElementSizeBytes * 8; |
| EVT StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW); |
| if (TLI.isTypeLegal(StoreTy)) |
| LastLegalType = i+1; |
| |
| // Find a legal type for the vector store. |
| EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, i+1); |
| if (TLI.isTypeLegal(Ty)) |
| LastLegalVectorType = i + 1; |
| } |
| |
| // We only use vectors if the constant is known to be zero and the |
| // function is not marked with the noimplicitfloat attribute. |
| if (NonZero || NoVectors) |
| LastLegalVectorType = 0; |
| |
| // Check if we found a legal integer type to store. |
| if (LastLegalType == 0 && LastLegalVectorType == 0) |
| return false; |
| |
| bool UseVector = (LastLegalVectorType > LastLegalType) && !NoVectors; |
| unsigned NumElem = UseVector ? LastLegalVectorType : LastLegalType; |
| |
| // Make sure we have something to merge. |
| if (NumElem < 2) |
| return false; |
| |
| unsigned EarliestNodeUsed = 0; |
| for (unsigned i=0; i < NumElem; ++i) { |
| // Find a chain for the new wide-store operand. Notice that some |
| // of the store nodes that we found may not be selected for inclusion |
| // in the wide store. The chain we use needs to be the chain of the |
| // earliest store node which is *used* and replaced by the wide store. |
| if (StoreNodes[i].SequenceNum > StoreNodes[EarliestNodeUsed].SequenceNum) |
| EarliestNodeUsed = i; |
| } |
| |
| // The earliest Node in the DAG. |
| LSBaseSDNode *EarliestOp = StoreNodes[EarliestNodeUsed].MemNode; |
| DebugLoc DL = StoreNodes[0].MemNode->getDebugLoc(); |
| |
| SDValue StoredVal; |
| if (UseVector) { |
| // Find a legal type for the vector store. |
| EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, NumElem); |
| assert(TLI.isTypeLegal(Ty) && "Illegal vector store"); |
| StoredVal = DAG.getConstant(0, Ty); |
| } else { |
| unsigned StoreBW = NumElem * ElementSizeBytes * 8; |
| APInt StoreInt(StoreBW, 0); |
| |
| // Construct a single integer constant which is made of the smaller |
| // constant inputs. |
| bool IsLE = TLI.isLittleEndian(); |
| for (unsigned i = 0; i < NumElem ; ++i) { |
| unsigned Idx = IsLE ?(NumElem - 1 - i) : i; |
| StoreSDNode *St = cast<StoreSDNode>(StoreNodes[Idx].MemNode); |
| SDValue Val = St->getValue(); |
| StoreInt<<=ElementSizeBytes*8; |
| if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val)) { |
| StoreInt|=C->getAPIntValue().zext(StoreBW); |
| } else if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Val)) { |
| StoreInt|= C->getValueAPF().bitcastToAPInt().zext(StoreBW); |
| } else { |
| assert(false && "Invalid constant element type"); |
| } |
| } |
| |
| // Create the new Load and Store operations. |
| EVT StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW); |
| StoredVal = DAG.getConstant(StoreInt, StoreTy); |
| } |
| |
| SDValue NewStore = DAG.getStore(EarliestOp->getChain(), DL, StoredVal, |
| FirstInChain->getBasePtr(), |
| FirstInChain->getPointerInfo(), |
| false, false, |
| FirstInChain->getAlignment()); |
| |
| // Replace the first store with the new store |
| CombineTo(EarliestOp, NewStore); |
| // Erase all other stores. |
| for (unsigned i = 0; i < NumElem ; ++i) { |
| if (StoreNodes[i].MemNode == EarliestOp) |
| continue; |
| StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode); |
| // ReplaceAllUsesWith will replace all uses that existed when it was |
| // called, but graph optimizations may cause new ones to appear. For |
| // example, the case in pr14333 looks like |
| // |
| // St's chain -> St -> another store -> X |
| // |
| // And the only difference from St to the other store is the chain. |
| // When we change it's chain to be St's chain they become identical, |
| // get CSEed and the net result is that X is now a use of St. |
| // Since we know that St is redundant, just iterate. |
| while (!St->use_empty()) |
| DAG.ReplaceAllUsesWith(SDValue(St, 0), St->getChain()); |
| removeFromWorkList(St); |
| DAG.DeleteNode(St); |
| } |
| |
| return true; |
| } |
| |
| // Below we handle the case of multiple consecutive stores that |
| // come from multiple consecutive loads. We merge them into a single |
| // wide load and a single wide store. |
| |
| // Look for load nodes which are used by the stored values. |
| SmallVector<MemOpLink, 8> LoadNodes; |
| |
| // Find acceptable loads. Loads need to have the same chain (token factor), |
| // must not be zext, volatile, indexed, and they must be consecutive. |
| SDValue LdBasePtr; |
| for (unsigned i=0; i<LastConsecutiveStore+1; ++i) { |
| StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode); |
| LoadSDNode *Ld = dyn_cast<LoadSDNode>(St->getValue()); |
| if (!Ld) break; |
| |
| // Loads must only have one use. |
| if (!Ld->hasNUsesOfValue(1, 0)) |
| break; |
| |
| // Check that the alignment is the same as the stores. |
| if (Ld->getAlignment() != St->getAlignment()) |
| break; |
| |
| // The memory operands must not be volatile. |
| if (Ld->isVolatile() || Ld->isIndexed()) |
| break; |
| |
| // We do not accept ext loads. |
| if (Ld->getExtensionType() != ISD::NON_EXTLOAD) |
| break; |
| |
| // The stored memory type must be the same. |
| if (Ld->getMemoryVT() != MemVT) |
| break; |
| |
| std::pair<SDValue, int64_t> LdPtr = |
| GetPointerBaseAndOffset(Ld->getBasePtr()); |
| |
| // If this is not the first ptr that we check. |
| if (LdBasePtr.getNode()) { |
| // The base ptr must be the same. |
| if (LdPtr.first != LdBasePtr) |
| break; |
| } else { |
| // Check that all other base pointers are the same as this one. |
| LdBasePtr = LdPtr.first; |
| } |
| |
| // We found a potential memory operand to merge. |
| LoadNodes.push_back(MemOpLink(Ld, LdPtr.second, 0)); |
| } |
| |
| if (LoadNodes.size() < 2) |
| return false; |
| |
| // Scan the memory operations on the chain and find the first non-consecutive |
| // load memory address. These variables hold the index in the store node |
| // array. |
| unsigned LastConsecutiveLoad = 0; |
| // This variable refers to the size and not index in the array. |
| unsigned LastLegalVectorType = 0; |
| unsigned LastLegalIntegerType = 0; |
| StartAddress = LoadNodes[0].OffsetFromBase; |
| SDValue FirstChain = LoadNodes[0].MemNode->getChain(); |
| for (unsigned i = 1; i < LoadNodes.size(); ++i) { |
| // All loads much share the same chain. |
| if (LoadNodes[i].MemNode->getChain() != FirstChain) |
| break; |
| |
| int64_t CurrAddress = LoadNodes[i].OffsetFromBase; |
| if (CurrAddress - StartAddress != (ElementSizeBytes * i)) |
| break; |
| LastConsecutiveLoad = i; |
| |
| // Find a legal type for the vector store. |
| EVT StoreTy = EVT::getVectorVT(*DAG.getContext(), MemVT, i+1); |
| if (TLI.isTypeLegal(StoreTy)) |
| LastLegalVectorType = i + 1; |
| |
| // Find a legal type for the integer store. |
| unsigned StoreBW = (i+1) * ElementSizeBytes * 8; |
| StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW); |
| if (TLI.isTypeLegal(StoreTy)) |
| LastLegalIntegerType = i + 1; |
| } |
| |
| // Only use vector types if the vector type is larger than the integer type. |
| // If they are the same, use integers. |
| bool UseVectorTy = LastLegalVectorType > LastLegalIntegerType && !NoVectors; |
| unsigned LastLegalType = std::max(LastLegalVectorType, LastLegalIntegerType); |
| |
| // We add +1 here because the LastXXX variables refer to location while |
| // the NumElem refers to array/index size. |
| unsigned NumElem = std::min(LastConsecutiveStore, LastConsecutiveLoad) + 1; |
| NumElem = std::min(LastLegalType, NumElem); |
| |
| if (NumElem < 2) |
| return false; |
| |
| // The earliest Node in the DAG. |
| unsigned EarliestNodeUsed = 0; |
| LSBaseSDNode *EarliestOp = StoreNodes[EarliestNodeUsed].MemNode; |
| for (unsigned i=1; i<NumElem; ++i) { |
| // Find a chain for the new wide-store operand. Notice that some |
| // of the store nodes that we found may not be selected for inclusion |
| // in the wide store. The chain we use needs to be the chain of the |
| // earliest store node which is *used* and replaced by the wide store. |
| if (StoreNodes[i].SequenceNum > StoreNodes[EarliestNodeUsed].SequenceNum) |
| EarliestNodeUsed = i; |
| } |
| |
| // Find if it is better to use vectors or integers to load and store |
| // to memory. |
| EVT JointMemOpVT; |
| if (UseVectorTy) { |
| JointMemOpVT = EVT::getVectorVT(*DAG.getContext(), MemVT, NumElem); |
| } else { |
| unsigned StoreBW = NumElem * ElementSizeBytes * 8; |
| JointMemOpVT = EVT::getIntegerVT(*DAG.getContext(), StoreBW); |
| } |
| |
| DebugLoc LoadDL = LoadNodes[0].MemNode->getDebugLoc(); |
| DebugLoc StoreDL = StoreNodes[0].MemNode->getDebugLoc(); |
| |
| LoadSDNode *FirstLoad = cast<LoadSDNode>(LoadNodes[0].MemNode); |
| SDValue NewLoad = DAG.getLoad(JointMemOpVT, LoadDL, |
| FirstLoad->getChain(), |
| FirstLoad->getBasePtr(), |
| FirstLoad->getPointerInfo(), |
| false, false, false, |
| FirstLoad->getAlignment()); |
| |
| SDValue NewStore = DAG.getStore(EarliestOp->getChain(), StoreDL, NewLoad, |
| FirstInChain->getBasePtr(), |
| FirstInChain->getPointerInfo(), false, false, |
| FirstInChain->getAlignment()); |
| |
| // Replace one of the loads with the new load. |
| LoadSDNode *Ld = cast<LoadSDNode>(LoadNodes[0].MemNode); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(Ld, 1), |
| SDValue(NewLoad.getNode(), 1)); |
| |
| // Remove the rest of the load chains. |
| for (unsigned i = 1; i < NumElem ; ++i) { |
| // Replace all chain users of the old load nodes with the chain of the new |
| // load node. |
| LoadSDNode *Ld = cast<LoadSDNode>(LoadNodes[i].MemNode); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(Ld, 1), Ld->getChain()); |
| } |
| |
| // Replace the first store with the new store. |
| CombineTo(EarliestOp, NewStore); |
| // Erase all other stores. |
| for (unsigned i = 0; i < NumElem ; ++i) { |
| // Remove all Store nodes. |
| if (StoreNodes[i].MemNode == EarliestOp) |
| continue; |
| StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode); |
| DAG.ReplaceAllUsesOfValueWith(SDValue(St, 0), St->getChain()); |
| removeFromWorkList(St); |
| DAG.DeleteNode(St); |
| } |
| |
| return true; |
| } |
| |
| SDValue DAGCombiner::visitSTORE(SDNode *N) { |
| StoreSDNode *ST = cast<StoreSDNode>(N); |
| SDValue Chain = ST->getChain(); |
| SDValue Value = ST->getValue(); |
| SDValue Ptr = ST->getBasePtr(); |
| |
| // If this is a store of a bit convert, store the input value if the |
| // resultant store does not need a higher alignment than the original. |
| if (Value.getOpcode() == ISD::BITCAST && !ST->isTruncatingStore() && |
| ST->isUnindexed()) { |
| unsigned OrigAlign = ST->getAlignment(); |
| EVT SVT = Value.getOperand(0).getValueType(); |
| unsigned Align = TLI.getDataLayout()-> |
| getABITypeAlignment(SVT.getTypeForEVT(*DAG.getContext())); |
| if (Align <= OrigAlign && |
| ((!LegalOperations && !ST->isVolatile()) || |
| TLI.isOperationLegalOrCustom(ISD::STORE, SVT))) |
| return DAG.getStore(Chain, N->getDebugLoc(), Value.getOperand(0), |
| Ptr, ST->getPointerInfo(), ST->isVolatile(), |
| ST->isNonTemporal(), OrigAlign); |
| } |
| |
| // Turn 'store undef, Ptr' -> nothing. |
| if (Value.getOpcode() == ISD::UNDEF && ST->isUnindexed()) |
| return Chain; |
| |
| // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr' |
| if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Value)) { |
| // NOTE: If the original store is volatile, this transform must not increase |
| // the number of stores. For example, on x86-32 an f64 can be stored in one |
| // processor operation but an i64 (which is not legal) requires two. So the |
| // transform should not be done in this case. |
| if (Value.getOpcode() != ISD::TargetConstantFP) { |
| SDValue Tmp; |
| switch (CFP->getValueType(0).getSimpleVT().SimpleTy) { |
| default: llvm_unreachable("Unknown FP type"); |
| case MVT::f16: // We don't do this for these yet. |
| case MVT::f80: |
| case MVT::f128: |
| case MVT::ppcf128: |
| break; |
| case MVT::f32: |
| if ((isTypeLegal(MVT::i32) && !LegalOperations && !ST->isVolatile()) || |
| TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) { |
| Tmp = DAG.getConstant((uint32_t)CFP->getValueAPF(). |
| bitcastToAPInt().getZExtValue(), MVT::i32); |
| return DAG.getStore(Chain, N->getDebugLoc(), Tmp, |
| Ptr, ST->getPointerInfo(), ST->isVolatile(), |
| ST->isNonTemporal(), ST->getAlignment()); |
| } |
| break; |
| case MVT::f64: |
| if ((TLI.isTypeLegal(MVT::i64) && !LegalOperations && |
| !ST->isVolatile()) || |
| TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i64)) { |
| Tmp = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt(). |
| getZExtValue(), MVT::i64); |
| return DAG.getStore(Chain, N->getDebugLoc(), Tmp, |
| Ptr, ST->getPointerInfo(), ST->isVolatile(), |
| ST->isNonTemporal(), ST->getAlignment()); |
| } |
| |
| if (!ST->isVolatile() && |
| TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) { |
| // Many FP stores are not made apparent until after legalize, e.g. for |
| // argument passing. Since this is so common, custom legalize the |
| // 64-bit integer store into two 32-bit stores. |
| uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); |
| SDValue Lo = DAG.getConstant(Val & 0xFFFFFFFF, MVT::i32); |
| SDValue Hi = DAG.getConstant(Val >> 32, MVT::i32); |
| if (TLI.isBigEndian()) std::swap(Lo, Hi); |
| |
| unsigned Alignment = ST->getAlignment(); |
| bool isVolatile = ST->isVolatile(); |
| bool isNonTemporal = ST->isNonTemporal(); |
| |
| SDValue St0 = DAG.getStore(Chain, ST->getDebugLoc(), Lo, |
| Ptr, ST->getPointerInfo(), |
| isVolatile, isNonTemporal, |
| ST->getAlignment()); |
| Ptr = DAG.getNode(ISD::ADD, N->getDebugLoc(), Ptr.getValueType(), Ptr, |
| DAG.getConstant(4, Ptr.getValueType())); |
| Alignment = MinAlign(Alignment, 4U); |
| SDValue St1 = DAG.getStore(Chain, ST->getDebugLoc(), Hi, |
| Ptr, ST->getPointerInfo().getWithOffset(4), |
| isVolatile, isNonTemporal, |
| Alignment); |
| return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other, |
| St0, St1); |
| } |
| |
| break; |
| } |
| } |
| } |
| |
| // Try to infer better alignment information than the store already has. |
| if (OptLevel != CodeGenOpt::None && ST->isUnindexed()) { |
| if (unsigned Align = DAG.InferPtrAlignment(Ptr)) { |
| if (Align > ST->getAlignment()) |
| return DAG.getTruncStore(Chain, N->getDebugLoc(), Value, |
| Ptr, ST->getPointerInfo(), ST->getMemoryVT(), |
| ST->isVolatile(), ST->isNonTemporal(), Align); |
| } |
| } |
| |
| // Try transforming a pair floating point load / store ops to integer |
| // load / store ops. |
| SDValue NewST = TransformFPLoadStorePair(N); |
| if (NewST.getNode()) |
| return NewST; |
| |
| if (CombinerAA) { |
| // Walk up chain skipping non-aliasing memory nodes. |
| SDValue BetterChain = FindBetterChain(N, Chain); |
| |
| // If there is a better chain. |
| if (Chain != BetterChain) { |
| SDValue ReplStore; |
| |
| // Replace the chain to avoid dependency. |
| if (ST->isTruncatingStore()) { |
| ReplStore = DAG.getTruncStore(BetterChain, N->getDebugLoc(), Value, Ptr, |
| ST->getPointerInfo(), |
| ST->getMemoryVT(), ST->isVolatile(), |
| ST->isNonTemporal(), ST->getAlignment()); |
| } else { |
| ReplStore = DAG.getStore(BetterChain, N->getDebugLoc(), Value, Ptr, |
| ST->getPointerInfo(), |
| ST->isVolatile(), ST->isNonTemporal(), |
| ST->getAlignment()); |
| } |
| |
| // Create token to keep both nodes around. |
| SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), |
| MVT::Other, Chain, ReplStore); |
| |
| // Make sure the new and old chains are cleaned up. |
| AddToWorkList(Token.getNode()); |
| |
| // Don't add users to work list. |
| return CombineTo(N, Token, false); |
| } |
| } |
| |
| // Try transforming N to an indexed store. |
| if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N)) |
| return SDValue(N, 0); |
| |
| // FIXME: is there such a thing as a truncating indexed store? |
| if (ST->isTruncatingStore() && ST->isUnindexed() && |
| Value.getValueType().isInteger()) { |
| // See if we can simplify the input to this truncstore with knowledge that |
| // only the low bits are being used. For example: |
| // "truncstore (or (shl x, 8), y), i8" -> "truncstore y, i8" |
| SDValue Shorter = |
| GetDemandedBits(Value, |
| APInt::getLowBitsSet( |
| Value.getValueType().getScalarType().getSizeInBits(), |
| ST->getMemoryVT().getScalarType().getSizeInBits())); |
| AddToWorkList(Value.getNode()); |
| if (Shorter.getNode()) |
| return DAG.getTruncStore(Chain, N->getDebugLoc(), Shorter, |
| Ptr, ST->getPointerInfo(), ST->getMemoryVT(), |
| ST->isVolatile(), ST->isNonTemporal(), |
| ST->getAlignment()); |
| |
| // Otherwise, see if we can simplify the operation with |
| // SimplifyDemandedBits, which only works if the value has a single use. |
| if (SimplifyDemandedBits(Value, |
| APInt::getLowBitsSet( |
| Value.getValueType().getScalarType().getSizeInBits(), |
| ST->getMemoryVT().getScalarType().getSizeInBits()))) |
| return SDValue(N, 0); |
| } |
| |
| // If this is a load followed by a store to the same location, then the store |
| // is dead/noop. |
| if (LoadSDNode *Ld = dyn_cast<LoadSDNode>(Value)) { |
| if (Ld->getBasePtr() == Ptr && ST->getMemoryVT() == Ld->getMemoryVT() && |
| ST->isUnindexed() && !ST->isVolatile() && |
| // There can't be any side effects between the load and store, such as |
| // a call or store. |
| Chain.reachesChainWithoutSideEffects(SDValue(Ld, 1))) { |
| // The store is dead, remove it. |
| return Chain; |
| } |
| } |
| |
| // If this is an FP_ROUND or TRUNC followed by a store, fold this into a |
| // truncating store. We can do this even if this is already a truncstore. |
| if ((Value.getOpcode() == ISD::FP_ROUND || Value.getOpcode() == ISD::TRUNCATE) |
| && Value.getNode()->hasOneUse() && ST->isUnindexed() && |
| TLI.isTruncStoreLegal(Value.getOperand(0).getValueType(), |
| ST->getMemoryVT())) { |
| return DAG.getTruncStore(Chain, N->getDebugLoc(), Value.getOperand(0), |
| Ptr, ST->getPointerInfo(), ST->getMemoryVT(), |
| ST->isVolatile(), ST->isNonTemporal(), |
| ST->getAlignment()); |
| } |
| |
| // Only perform this optimization before the types are legal, because we |
| // don't want to perform this optimization on every DAGCombine invocation. |
| if (!LegalTypes) { |
| bool EverChanged = false; |
| |
| do { |
| // There can be multiple store sequences on the same chain. |
| // Keep trying to merge store sequences until we are unable to do so |
| // or until we merge the last store on the chain. |
| bool Changed = MergeConsecutiveStores(ST); |
| EverChanged |= Changed; |
| if (!Changed) break; |
| } while (ST->getOpcode() != ISD::DELETED_NODE); |
| |
| if (EverChanged) |
| return SDValue(N, 0); |
| } |
| |
| return ReduceLoadOpStoreWidth(N); |
| } |
| |
| SDValue DAGCombiner::visitINSERT_VECTOR_ELT(SDNode *N) { |
| SDValue InVec = N->getOperand(0); |
| SDValue InVal = N->getOperand(1); |
| SDValue EltNo = N->getOperand(2); |
| DebugLoc dl = N->getDebugLoc(); |
| |
| // If the inserted element is an UNDEF, just use the input vector. |
| if (InVal.getOpcode() == ISD::UNDEF) |
| return InVec; |
| |
| EVT VT = InVec.getValueType(); |
| |
| // If we can't generate a legal BUILD_VECTOR, exit |
| if (LegalOperations && !TLI.isOperationLegal(ISD::BUILD_VECTOR, VT)) |
| return SDValue(); |
| |
| // Check that we know which element is being inserted |
| if (!isa<ConstantSDNode>(EltNo)) |
| return SDValue(); |
| unsigned Elt = cast<ConstantSDNode>(EltNo)->getZExtValue(); |
| |
| // Check that the operand is a BUILD_VECTOR (or UNDEF, which can essentially |
| // be converted to a BUILD_VECTOR). Fill in the Ops vector with the |
| // vector elements. |
| SmallVector<SDValue, 8> Ops; |
| if (InVec.getOpcode() == ISD::BUILD_VECTOR) { |
| Ops.append(InVec.getNode()->op_begin(), |
| InVec.getNode()->op_end()); |
| } else if (InVec.getOpcode() == ISD::UNDEF) { |
| unsigned NElts = VT.getVectorNumElements(); |
| Ops.append(NElts, DAG.getUNDEF(InVal.getValueType())); |
| } else { |
| return SDValue(); |
| } |
| |
| // Insert the element |
| if (Elt < Ops.size()) { |
| // All the operands of BUILD_VECTOR must have the same type; |
| // we enforce that here. |
| EVT OpVT = Ops[0].getValueType(); |
| if (InVal.getValueType() != OpVT) |
| InVal = OpVT.bitsGT(InVal.getValueType()) ? |
| DAG.getNode(ISD::ANY_EXTEND, dl, OpVT, InVal) : |
| DAG.getNode(ISD::TRUNCATE, dl, OpVT, InVal); |
| Ops[Elt] = InVal; |
| } |
| |
| // Return the new vector |
| return DAG.getNode(ISD::BUILD_VECTOR, dl, |
| VT, &Ops[0], Ops.size()); |
| } |
| |
| SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) { |
| // (vextract (scalar_to_vector val, 0) -> val |
| SDValue InVec = N->getOperand(0); |
| EVT VT = InVec.getValueType(); |
| EVT NVT = N->getValueType(0); |
| |
| if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR) { |
| // Check if the result type doesn't match the inserted element type. A |
| // SCALAR_TO_VECTOR may truncate the inserted element and the |
| // EXTRACT_VECTOR_ELT may widen the extracted vector. |
| SDValue InOp = InVec.getOperand(0); |
| if (InOp.getValueType() != NVT) { |
| assert(InOp.getValueType().isInteger() && NVT.isInteger()); |
| return DAG.getSExtOrTrunc(InOp, InVec.getDebugLoc(), NVT); |
| } |
| return InOp; |
| } |
| |
| SDValue EltNo = N->getOperand(1); |
| bool ConstEltNo = isa<ConstantSDNode>(EltNo); |
| |
| // Transform: (EXTRACT_VECTOR_ELT( VECTOR_SHUFFLE )) -> EXTRACT_VECTOR_ELT. |
| // We only perform this optimization before the op legalization phase because |
| // we may introduce new vector instructions which are not backed by TD |
| // patterns. For example on AVX, extracting elements from a wide vector |
| // without using extract_subvector. |
| if (InVec.getOpcode() == ISD::VECTOR_SHUFFLE |
| && ConstEltNo && !LegalOperations) { |
| int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue(); |
| int NumElem = VT.getVectorNumElements(); |
| ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(InVec); |
| // Find the new index to extract from. |
| int OrigElt = SVOp->getMaskElt(Elt); |
| |
| // Extracting an undef index is undef. |
| if (OrigElt == -1) |
| return DAG.getUNDEF(NVT); |
| |
| // Select the right vector half to extract from. |
| if (OrigElt < NumElem) { |
| InVec = InVec->getOperand(0); |
| } else { |
| InVec = InVec->getOperand(1); |
| OrigElt -= NumElem; |
| } |
| |
| EVT IndexTy = N->getOperand(1).getValueType(); |
| return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, N->getDebugLoc(), NVT, |
| InVec, DAG.getConstant(OrigElt, IndexTy)); |
| } |
| |
| // Perform only after legalization to ensure build_vector / vector_shuffle |
| // optimizations have already been done. |
| if (!LegalOperations) return SDValue(); |
| |
| // (vextract (v4f32 load $addr), c) -> (f32 load $addr+c*size) |
| // (vextract (v4f32 s2v (f32 load $addr)), c) -> (f32 load $addr+c*size) |
| // (vextract (v4f32 shuffle (load $addr), <1,u,u,u>), 0) -> (f32 load $addr) |
| |
| if (ConstEltNo) { |
| int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue(); |
| bool NewLoad = false; |
| bool BCNumEltsChanged = false; |
| EVT ExtVT = VT.getVectorElementType(); |
| EVT LVT = ExtVT; |
| |
| // If the result of load has to be truncated, then it's not necessarily |
| // profitable. |
| if (NVT.bitsLT(LVT) && !TLI.isTruncateFree(LVT, NVT)) |
| return SDValue(); |
| |
| if (InVec.getOpcode() == ISD::BITCAST) { |
| // Don't duplicate a load with other uses. |
| if (!InVec.hasOneUse()) |
| return SDValue(); |
| |
| EVT BCVT = InVec.getOperand(0).getValueType(); |
| if (!BCVT.isVector() || ExtVT.bitsGT(BCVT.getVectorElementType())) |
| return SDValue(); |
| if (VT.getVectorNumElements() != BCVT.getVectorNumElements()) |
| BCNumEltsChanged = true; |
| InVec = InVec.getOperand(0); |
| ExtVT = BCVT.getVectorElementType(); |
| NewLoad = true; |
| } |
| |
| LoadSDNode *LN0 = NULL; |
| const ShuffleVectorSDNode *SVN = NULL; |
| if (ISD::isNormalLoad(InVec.getNode())) { |
| LN0 = cast<LoadSDNode>(InVec); |
| } else if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR && |
| InVec.getOperand(0).getValueType() == ExtVT && |
| ISD::isNormalLoad(InVec.getOperand(0).getNode())) { |
| // Don't duplicate a load with other uses. |
| if (!InVec.hasOneUse()) |
| return SDValue(); |
| |
| LN0 = cast<LoadSDNode>(InVec.getOperand(0)); |
| } else if ((SVN = dyn_cast<ShuffleVectorSDNode>(InVec))) { |
| // (vextract (vector_shuffle (load $addr), v2, <1, u, u, u>), 1) |
| // => |
| // (load $addr+1*size) |
| |
| // Don't duplicate a load with other uses. |
| if (!InVec.hasOneUse()) |
| return SDValue(); |
| |
| // If the bit convert changed the number of elements, it is unsafe |
| // to examine the mask. |
| if (BCNumEltsChanged) |
| return SDValue(); |
| |
| // Select the input vector, guarding against out of range extract vector. |
| unsigned NumElems = VT.getVectorNumElements(); |
| int Idx = (Elt > (int)NumElems) ? -1 : SVN->getMaskElt(Elt); |
| InVec = (Idx < (int)NumElems) ? InVec.getOperand(0) : InVec.getOperand(1); |
| |
| if (InVec.getOpcode() == ISD::BITCAST) { |
| // Don't duplicate a load with other uses. |
| if (!InVec.hasOneUse()) |
| return SDValue(); |
| |
| InVec = InVec.getOperand(0); |
| } |
| if (ISD::isNormalLoad(InVec.getNode())) { |
| LN0 = cast<LoadSDNode>(InVec); |
| Elt = (Idx < (int)NumElems) ? Idx : Idx - (int)NumElems; |
| } |
| } |
| |
| // Make sure we found a non-volatile load and the extractelement is |
| // the only use. |
| if (!LN0 || !LN0->hasNUsesOfValue(1,0) || LN0->isVolatile()) |
| return SDValue(); |
| |
| // If Idx was -1 above, Elt is going to be -1, so just return undef. |
| if (Elt == -1) |
| return DAG.getUNDEF(LVT); |
| |
| unsigned Align = LN0->getAlignment(); |
| if (NewLoad) { |
| // Check the resultant load doesn't need a higher alignment than the |
| // original load. |
| unsigned NewAlign = |
| TLI.getDataLayout() |
| ->getABITypeAlignment(LVT.getTypeForEVT(*DAG.getContext())); |
| |
| if (NewAlign > Align || !TLI.isOperationLegalOrCustom(ISD::LOAD, LVT)) |
| return SDValue(); |
| |
| Align = NewAlign; |
| } |
| |
| SDValue NewPtr = LN0->getBasePtr(); |
| unsigned PtrOff = 0; |
| |
| if (Elt) { |
| PtrOff = LVT.getSizeInBits() * Elt / 8; |
| EVT PtrType = NewPtr.getValueType(); |
| if (TLI.isBigEndian()) |
| PtrOff = VT.getSizeInBits() / 8 - PtrOff; |
| NewPtr = DAG.getNode(ISD::ADD, N->getDebugLoc(), PtrType, NewPtr, |
| DAG.getConstant(PtrOff, PtrType)); |
| } |
| |
| // The replacement we need to do here is a little tricky: we need to |
| // replace an extractelement of a load with a load. |
| // Use ReplaceAllUsesOfValuesWith to do the replacement. |
| // Note that this replacement assumes that the extractvalue is the only |
| // use of the load; that's okay because we don't want to perform this |
| // transformation in other cases anyway. |
| SDValue Load; |
| SDValue Chain; |
| if (NVT.bitsGT(LVT)) { |
| // If the result type of vextract is wider than the load, then issue an |
| // extending load instead. |
| ISD::LoadExtType ExtType = TLI.isLoadExtLegal(ISD::ZEXTLOAD, LVT) |
| ? ISD::ZEXTLOAD : ISD::EXTLOAD; |
| Load = DAG.getExtLoad(ExtType, N->getDebugLoc(), NVT, LN0->getChain(), |
| NewPtr, LN0->getPointerInfo().getWithOffset(PtrOff), |
| LVT, LN0->isVolatile(), LN0->isNonTemporal(),Align); |
| Chain = Load.getValue(1); |
| } else { |
| Load = DAG.getLoad(LVT, N->getDebugLoc(), LN0->getChain(), NewPtr, |
| LN0->getPointerInfo().getWithOffset(PtrOff), |
| LN0->isVolatile(), LN0->isNonTemporal(), |
| LN0->isInvariant(), Align); |
| Chain = Load.getValue(1); |
| if (NVT.bitsLT(LVT)) |
| Load = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), NVT, Load); |
| else |
| Load = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), NVT, Load); |
| } |
| WorkListRemover DeadNodes(*this); |
| SDValue From[] = { SDValue(N, 0), SDValue(LN0,1) }; |
| SDValue To[] = { Load, Chain }; |
| DAG.ReplaceAllUsesOfValuesWith(From, To, 2); |
| // Since we're explcitly calling ReplaceAllUses, add the new node to the |
| // worklist explicitly as well. |
| AddToWorkList(Load.getNode()); |
| AddUsersToWorkList(Load.getNode()); // Add users too |
| // Make sure to revisit this node to clean it up; it will usually be dead. |
| AddToWorkList(N); |
| return SDValue(N, 0); |
| } |
| |
| return SDValue(); |
| } |
| |
| // Simplify (build_vec (ext )) to (bitcast (build_vec )) |
| SDValue DAGCombiner::reduceBuildVecExtToExtBuildVec(SDNode *N) { |
| // We perform this optimization post type-legalization because |
| // the type-legalizer often scalarizes integer-promoted vectors. |
| // Performing this optimization before may create bit-casts which |
| // will be type-legalized to complex code sequences. |
| // We perform this optimization only before the operation legalizer because we |
| // may introduce illegal operations. |
| if (Level != AfterLegalizeVectorOps && Level != AfterLegalizeTypes) |
| return SDValue(); |
| |
| unsigned NumInScalars = N->getNumOperands(); |
| DebugLoc dl = N->getDebugLoc(); |
| EVT VT = N->getValueType(0); |
| |
| // Check to see if this is a BUILD_VECTOR of a bunch of values |
| // which come from any_extend or zero_extend nodes. If so, we can create |
| // a new BUILD_VECTOR using bit-casts which may enable other BUILD_VECTOR |
| // optimizations. We do not handle sign-extend because we can't fill the sign |
| // using shuffles. |
| EVT SourceType = MVT::Other; |
| bool AllAnyExt = true; |
| |
| for (unsigned i = 0; i != NumInScalars; ++i) { |
| SDValue In = N->getOperand(i); |
| // Ignore undef inputs. |
| if (In.getOpcode() == ISD::UNDEF) continue; |
| |
| bool AnyExt = In.getOpcode() == ISD::ANY_EXTEND; |
| bool ZeroExt = In.getOpcode() == ISD::ZERO_EXTEND; |
| |
| // Abort if the element is not an extension. |
| if (!ZeroExt && !AnyExt) { |
| SourceType = MVT::Other; |
| break; |
| } |
| |
| // The input is a ZeroExt or AnyExt. Check the original type. |
| EVT InTy = In.getOperand(0).getValueType(); |
| |
| // Check that all of the widened source types are the same. |
| if (SourceType == MVT::Other) |
| // First time. |
| SourceType = InTy; |
| else if (InTy != SourceType) { |
| // Multiple income types. Abort. |
| SourceType = MVT::Other; |
| break; |
| } |
| |
| // Check if all of the extends are ANY_EXTENDs. |
| AllAnyExt &= AnyExt; |
| } |
| |
| // In order to have valid types, all of the inputs must be extended from the |
| // same source type and all of the inputs must be any or zero extend. |
| // Scalar sizes must be a power of two. |
| EVT OutScalarTy = VT.getScalarType(); |
| bool ValidTypes = SourceType != MVT::Other && |
| isPowerOf2_32(OutScalarTy.getSizeInBits()) && |
| isPowerOf2_32(SourceType.getSizeInBits()); |
| |
| // Create a new simpler BUILD_VECTOR sequence which other optimizations can |
| // turn into a single shuffle instruction. |
| if (!ValidTypes) |
| return SDValue(); |
| |
| bool isLE = TLI.isLittleEndian(); |
| unsigned ElemRatio = OutScalarTy.getSizeInBits()/SourceType.getSizeInBits(); |
| assert(ElemRatio > 1 && "Invalid element size ratio"); |
| SDValue Filler = AllAnyExt ? DAG.getUNDEF(SourceType): |
| DAG.getConstant(0, SourceType); |
| |
| unsigned NewBVElems = ElemRatio * VT.getVectorNumElements(); |
| SmallVector<SDValue, 8> Ops(NewBVElems, Filler); |
| |
| // Populate the new build_vector |
| for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) { |
| SDValue Cast = N->getOperand(i); |
| assert((Cast.getOpcode() == ISD::ANY_EXTEND || |
| Cast.getOpcode() == ISD::ZERO_EXTEND || |
| Cast.getOpcode() == ISD::UNDEF) && "Invalid cast opcode"); |
| SDValue In; |
| if (Cast.getOpcode() == ISD::UNDEF) |
| In = DAG.getUNDEF(SourceType); |
| else |
| In = Cast->getOperand(0); |
| unsigned Index = isLE ? (i * ElemRatio) : |
| (i * ElemRatio + (ElemRatio - 1)); |
| |
| assert(Index < Ops.size() && "Invalid index"); |
| Ops[Index] = In; |
| } |
| |
| // The type of the new BUILD_VECTOR node. |
| EVT VecVT = EVT::getVectorVT(*DAG.getContext(), SourceType, NewBVElems); |
| assert(VecVT.getSizeInBits() == VT.getSizeInBits() && |
| "Invalid vector size"); |
| // Check if the new vector type is legal. |
| if (!isTypeLegal(VecVT)) return SDValue(); |
| |
| // Make the new BUILD_VECTOR. |
| SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, dl, VecVT, &Ops[0], Ops.size()); |
| |
| // The new BUILD_VECTOR node has the potential to be further optimized. |
| AddToWorkList(BV.getNode()); |
| // Bitcast to the desired type. |
| return DAG.getNode(ISD::BITCAST, dl, VT, BV); |
| } |
| |
| SDValue DAGCombiner::reduceBuildVecConvertToConvertBuildVec(SDNode *N) { |
| EVT VT = N->getValueType(0); |
| |
| unsigned NumInScalars = N->getNumOperands(); |
| DebugLoc dl = N->getDebugLoc(); |
| |
| EVT SrcVT = MVT::Other; |
| unsigned Opcode = ISD::DELETED_NODE; |
| unsigned NumDefs = 0; |
| |
| for (unsigned i = 0; i != NumInScalars; ++i) { |
| SDValue In = N->getOperand(i); |
| unsigned Opc = In.getOpcode(); |
| |
| if (Opc == ISD::UNDEF) |
| continue; |
| |
| // If all scalar values are floats and converted from integers. |
| if (Opcode == ISD::DELETED_NODE && |
| (Opc == ISD::UINT_TO_FP || Opc == ISD::SINT_TO_FP)) { |
| Opcode = Opc; |
| } |
| |
| if (Opc != Opcode) |
| return SDValue(); |
| |
| EVT InVT = In.getOperand(0).getValueType(); |
| |
| // If all scalar values are typed differently, bail out. It's chosen to |
| // simplify BUILD_VECTOR of integer types. |
| if (SrcVT == MVT::Other) |
| SrcVT = InVT; |
| if (SrcVT != InVT) |
| return SDValue(); |
| NumDefs++; |
| } |
| |
| // If the vector has just one element defined, it's not worth to fold it into |
| // a vectorized one. |
| if (NumDefs < 2) |
| return SDValue(); |
| |
| assert((Opcode == ISD::UINT_TO_FP || Opcode == ISD::SINT_TO_FP) |
| && "Should only handle conversion from integer to float."); |
| assert(SrcVT != MVT::Other && "Cannot determine source type!"); |
| |
| EVT NVT = EVT::getVectorVT(*DAG.getContext(), SrcVT, NumInScalars); |
| |
| if (!TLI.isOperationLegalOrCustom(Opcode, NVT)) |
| return SDValue(); |
| |
| SmallVector<SDValue, 8> Opnds; |
| for (unsigned i = 0; i != NumInScalars; ++i) { |
| SDValue In = N->getOperand(i); |
| |
| if (In.getOpcode() == ISD::UNDEF) |
| Opnds.push_back(DAG.getUNDEF(SrcVT)); |
| else |
| Opnds.push_back(In.getOperand(0)); |
| } |
| SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, |
| &Opnds[0], Opnds.size()); |
| AddToWorkList(BV.getNode()); |
| |
| return DAG.getNode(Opcode, dl, VT, BV); |
| } |
| |
| SDValue DAGCombiner::visitBUILD_VECTOR(SDNode *N) { |
| unsigned NumInScalars = N->getNumOperands(); |
| DebugLoc dl = N->getDebugLoc(); |
| EVT VT = N->getValueType(0); |
| |
| // A vector built entirely of undefs is undef. |
| if (ISD::allOperandsUndef(N)) |
| return DAG.getUNDEF(VT); |
| |
| SDValue V = reduceBuildVecExtToExtBuildVec(N); |
| if (V.getNode()) |
| return V; |
| |
| V = reduceBuildVecConvertToConvertBuildVec(N); |
| if (V.getNode()) |
| return V; |
| |
| // Check to see if this is a BUILD_VECTOR of a bunch of EXTRACT_VECTOR_ELT |
| // operations. If so, and if the EXTRACT_VECTOR_ELT vector inputs come from |
| // at most two distinct vectors, turn this into a shuffle node. |
| |
| // May only combine to shuffle after legalize if shuffle is legal. |
| if (LegalOperations && |
| !TLI.isOperationLegalOrCustom(ISD::VECTOR_SHUFFLE, VT)) |
| return SDValue(); |
| |
| SDValue VecIn1, VecIn2; |
| for (unsigned i = 0; i != NumInScalars; ++i) { |
| // Ignore undef inputs. |
| if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue; |
| |
| // If this input is something other than a EXTRACT_VECTOR_ELT with a |
| // constant index, bail out. |
| if (N->getOperand(i).getOpcode() != ISD::EXTRACT_VECTOR_ELT || |
| !isa<ConstantSDNode>(N->getOperand(i).getOperand(1))) { |
| VecIn1 = VecIn2 = SDValue(0, 0); |
| break; |
| } |
| |
| // We allow up to two distinct input vectors. |
| SDValue ExtractedFromVec = N->getOperand(i).getOperand(0); |
| if (ExtractedFromVec == VecIn1 || ExtractedFromVec == VecIn2) |
| continue; |
| |
| if (VecIn1.getNode() == 0) { |
| VecIn1 = ExtractedFromVec; |
| } else if (VecIn2.getNode() == 0) { |
| VecIn2 = ExtractedFromVec; |
| } else { |
| // Too many inputs. |
| VecIn1 = VecIn2 = SDValue(0, 0); |
| break; |
| } |
| } |
| |
| // If everything is good, we can make a shuffle operation. |
| if (VecIn1.getNode()) { |
| SmallVector<int, 8> Mask; |
| for (unsigned i = 0; i != NumInScalars; ++i) { |
| if (N->getOperand(i).getOpcode() == ISD::UNDEF) { |
| Mask.push_back(-1); |
| continue; |
| } |
| |
| // If extracting from the first vector, just use the index directly. |
| SDValue Extract = N->getOperand(i); |
| SDValue ExtVal = Extract.getOperand(1); |
| if (Extract.getOperand(0) == VecIn1) { |
| unsigned ExtIndex = cast<ConstantSDNode>(ExtVal)->getZExtValue(); |
| if (ExtIndex > VT.getVectorNumElements()) |
| return SDValue(); |
| |
| Mask.push_back(ExtIndex); |
| continue; |
| } |
| |
| // Otherwise, use InIdx + VecSize |
| unsigned Idx = cast<ConstantSDNode>(ExtVal)->getZExtValue(); |
| Mask.push_back(Idx+NumInScalars); |
| } |
| |
| // We can't generate a shuffle node with mismatched input and output types. |
| // Attempt to transform a single input vector to the correct type. |
| if ((VT != VecIn1.getValueType())) { |
| // We don't support shuffeling between TWO values of different types. |
| if (VecIn2.getNode() != 0) |
| return SDValue(); |
| |
| // We only support widening of vectors which are half the size of the |
| // output registers. For example XMM->YMM widening on X86 with AVX. |
| if (VecIn1.getValueType().getSizeInBits()*2 != VT.getSizeInBits()) |
| return SDValue(); |
| |
| // If the input vector type has a different base type to the output |
| // vector type, bail out. |
| if (VecIn1.getValueType().getVectorElementType() != |
| VT.getVectorElementType()) |
| return SDValue(); |
| |
| // Widen the input vector by adding undef values. |
| VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, dl, VT, |
| VecIn1, DAG.getUNDEF(VecIn1.getValueType())); |
| } |
| |
| // If VecIn2 is unused then change it to undef. |
| VecIn2 = VecIn2.getNode() ? VecIn2 : DAG.getUNDEF(VT); |
| |
| // Check that we were able to transform all incoming values to the same |
| // type. |
| if (VecIn2.getValueType() != VecIn1.getValueType() || |
| VecIn1.getValueType() != VT) |
| return SDValue(); |
| |
| // Only type-legal BUILD_VECTOR nodes are converted to shuffle nodes. |
| if (!isTypeLegal(VT)) |
| return SDValue(); |
| |
| // Return the new VECTOR_SHUFFLE node. |
| SDValue Ops[2]; |
| Ops[0] = VecIn1; |
| Ops[1] = VecIn2; |
| return DAG.getVectorShuffle(VT, dl, Ops[0], Ops[1], &Mask[0]); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) { |
| // TODO: Check to see if this is a CONCAT_VECTORS of a bunch of |
| // EXTRACT_SUBVECTOR operations. If so, and if the EXTRACT_SUBVECTOR vector |
| // inputs come from at most two distinct vectors, turn this into a shuffle |
| // node. |
| |
| // If we only have one input vector, we don't need to do any concatenation. |
| if (N->getNumOperands() == 1) |
| return N->getOperand(0); |
| |
| // Check if all of the operands are undefs. |
| if (ISD::allOperandsUndef(N)) |
| return DAG.getUNDEF(N->getValueType(0)); |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitEXTRACT_SUBVECTOR(SDNode* N) { |
| EVT NVT = N->getValueType(0); |
| SDValue V = N->getOperand(0); |
| |
| if (V->getOpcode() == ISD::INSERT_SUBVECTOR) { |
| // Handle only simple case where vector being inserted and vector |
| // being extracted are of same type, and are half size of larger vectors. |
| EVT BigVT = V->getOperand(0).getValueType(); |
| EVT SmallVT = V->getOperand(1).getValueType(); |
| if (NVT != SmallVT || NVT.getSizeInBits()*2 != BigVT.getSizeInBits()) |
| return SDValue(); |
| |
| // Only handle cases where both indexes are constants with the same type. |
| ConstantSDNode *ExtIdx = dyn_cast<ConstantSDNode>(N->getOperand(1)); |
| ConstantSDNode *InsIdx = dyn_cast<ConstantSDNode>(V->getOperand(2)); |
| |
| if (InsIdx && ExtIdx && |
| InsIdx->getValueType(0).getSizeInBits() <= 64 && |
| ExtIdx->getValueType(0).getSizeInBits() <= 64) { |
| // Combine: |
| // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx) |
| // Into: |
| // indices are equal => V1 |
| // otherwise => (extract_subvec V1, ExtIdx) |
| if (InsIdx->getZExtValue() == ExtIdx->getZExtValue()) |
| return V->getOperand(1); |
| return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT, |
| V->getOperand(0), N->getOperand(1)); |
| } |
| } |
| |
| if (V->getOpcode() == ISD::CONCAT_VECTORS) { |
| // Combine: |
| // (extract_subvec (concat V1, V2, ...), i) |
| // Into: |
| // Vi if possible |
| // Only operand 0 is checked as 'concat' assumes all inputs of the same type. |
| if (V->getOperand(0).getValueType() != NVT) |
| return SDValue(); |
| unsigned Idx = dyn_cast<ConstantSDNode>(N->getOperand(1))->getZExtValue(); |
| unsigned NumElems = NVT.getVectorNumElements(); |
| assert((Idx % NumElems) == 0 && |
| "IDX in concat is not a multiple of the result vector length."); |
| return V->getOperand(Idx / NumElems); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) { |
| EVT VT = N->getValueType(0); |
| unsigned NumElts = VT.getVectorNumElements(); |
| |
| SDValue N0 = N->getOperand(0); |
| SDValue N1 = N->getOperand(1); |
| |
| assert(N0.getValueType() == VT && "Vector shuffle must be normalized in DAG"); |
| |
| // Canonicalize shuffle undef, undef -> undef |
| if (N0.getOpcode() == ISD::UNDEF && N1.getOpcode() == ISD::UNDEF) |
| return DAG.getUNDEF(VT); |
| |
| ShuffleVectorSDNode *SVN = cast<ShuffleVectorSDNode>(N); |
| |
| // Canonicalize shuffle v, v -> v, undef |
| if (N0 == N1) { |
| SmallVector<int, 8> NewMask; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| int Idx = SVN->getMaskElt(i); |
| if (Idx >= (int)NumElts) Idx -= NumElts; |
| NewMask.push_back(Idx); |
| } |
| return DAG.getVectorShuffle(VT, N->getDebugLoc(), N0, DAG.getUNDEF(VT), |
| &NewMask[0]); |
| } |
| |
| // Canonicalize shuffle undef, v -> v, undef. Commute the shuffle mask. |
| if (N0.getOpcode() == ISD::UNDEF) { |
| SmallVector<int, 8> NewMask; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| int Idx = SVN->getMaskElt(i); |
| if (Idx >= 0) { |
| if (Idx < (int)NumElts) |
| Idx += NumElts; |
| else |
| Idx -= NumElts; |
| } |
| NewMask.push_back(Idx); |
| } |
| return DAG.getVectorShuffle(VT, N->getDebugLoc(), N1, DAG.getUNDEF(VT), |
| &NewMask[0]); |
| } |
| |
| // Remove references to rhs if it is undef |
| if (N1.getOpcode() == ISD::UNDEF) { |
| bool Changed = false; |
| SmallVector<int, 8> NewMask; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| int Idx = SVN->getMaskElt(i); |
| if (Idx >= (int)NumElts) { |
| Idx = -1; |
| Changed = true; |
| } |
| NewMask.push_back(Idx); |
| } |
| if (Changed) |
| return DAG.getVectorShuffle(VT, N->getDebugLoc(), N0, N1, &NewMask[0]); |
| } |
| |
| // If it is a splat, check if the argument vector is another splat or a |
| // build_vector with all scalar elements the same. |
| if (SVN->isSplat() && SVN->getSplatIndex() < (int)NumElts) { |
| SDNode *V = N0.getNode(); |
| |
| // If this is a bit convert that changes the element type of the vector but |
| // not the number of vector elements, look through it. Be careful not to |
| // look though conversions that change things like v4f32 to v2f64. |
| if (V->getOpcode() == ISD::BITCAST) { |
| SDValue ConvInput = V->getOperand(0); |
| if (ConvInput.getValueType().isVector() && |
| ConvInput.getValueType().getVectorNumElements() == NumElts) |
| V = ConvInput.getNode(); |
| } |
| |
| if (V->getOpcode() == ISD::BUILD_VECTOR) { |
| assert(V->getNumOperands() == NumElts && |
| "BUILD_VECTOR has wrong number of operands"); |
| SDValue Base; |
| bool AllSame = true; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| if (V->getOperand(i).getOpcode() != ISD::UNDEF) { |
| Base = V->getOperand(i); |
| break; |
| } |
| } |
| // Splat of <u, u, u, u>, return <u, u, u, u> |
| if (!Base.getNode()) |
| return N0; |
| for (unsigned i = 0; i != NumElts; ++i) { |
| if (V->getOperand(i) != Base) { |
| AllSame = false; |
| break; |
| } |
| } |
| // Splat of <x, x, x, x>, return <x, x, x, x> |
| if (AllSame) |
| return N0; |
| } |
| } |
| |
| // If this shuffle node is simply a swizzle of another shuffle node, |
| // and it reverses the swizzle of the previous shuffle then we can |
| // optimize shuffle(shuffle(x, undef), undef) -> x. |
| if (N0.getOpcode() == ISD::VECTOR_SHUFFLE && Level < AfterLegalizeDAG && |
| N1.getOpcode() == ISD::UNDEF) { |
| |
| ShuffleVectorSDNode *OtherSV = cast<ShuffleVectorSDNode>(N0); |
| |
| // Shuffle nodes can only reverse shuffles with a single non-undef value. |
| if (N0.getOperand(1).getOpcode() != ISD::UNDEF) |
| return SDValue(); |
| |
| // The incoming shuffle must be of the same type as the result of the |
| // current shuffle. |
| assert(OtherSV->getOperand(0).getValueType() == VT && |
| "Shuffle types don't match"); |
| |
| for (unsigned i = 0; i != NumElts; ++i) { |
| int Idx = SVN->getMaskElt(i); |
| assert(Idx < (int)NumElts && "Index references undef operand"); |
| // Next, this index comes from the first value, which is the incoming |
| // shuffle. Adopt the incoming index. |
| if (Idx >= 0) |
| Idx = OtherSV->getMaskElt(Idx); |
| |
| // The combined shuffle must map each index to itself. |
| if (Idx >= 0 && (unsigned)Idx != i) |
| return SDValue(); |
| } |
| |
| return OtherSV->getOperand(0); |
| } |
| |
| return SDValue(); |
| } |
| |
| SDValue DAGCombiner::visitMEMBARRIER(SDNode* N) { |
| if (!TLI.getShouldFoldAtomicFences()) |
| return SDValue(); |
| |
| SDValue atomic = N->getOperand(0); |
| switch (atomic.getOpcode()) { |
| case ISD::ATOMIC_CMP_SWAP: |
| case ISD::ATOMIC_SWAP: |
| case ISD::ATOMIC_LOAD_ADD: |
| case ISD::ATOMIC_LOAD_SUB: |
| case ISD::ATOMIC_LOAD_AND: |
| case ISD::ATOMIC_LOAD_OR: |
| case ISD::ATOMIC_LOAD_XOR: |
| case ISD::ATOMIC_LOAD_NAND: |
| case ISD::ATOMIC_LOAD_MIN: |
| case ISD::ATOMIC_LOAD_MAX: |
| case ISD::ATOMIC_LOAD_UMIN: |
| case ISD::ATOMIC_LOAD_UMAX: |
| break; |
| default: |
| return SDValue(); |
| } |
| |
| SDValue fence = atomic.getOperand(0); |
| if (fence.getOpcode() != ISD::MEMBARRIER) |
| return SDValue(); |
| |
| switch (atomic.getOpcode()) { |
| case ISD::ATOMIC_CMP_SWAP: |
| return SDValue(DAG.UpdateNodeOperands(atomic.getNode(), |
| fence.getOperand(0), |
| atomic.getOperand(1), atomic.getOperand(2), |
| atomic.getOperand(3)), atomic.getResNo()); |
| case ISD::ATOMIC_SWAP: |
| case ISD::ATOMIC_LOAD_ADD: |
| case ISD::ATOMIC_LOAD_SUB: |
| case ISD::ATOMIC_LOAD_AND: |
| case ISD::ATOMIC_LOAD_OR: |
| case ISD::ATOMIC_LOAD_XOR: |
| case ISD::ATOMIC_LOAD_NAND: |
| case ISD::ATOMIC_LOAD_MIN: |
| case ISD::ATOMIC_LOAD_MAX: |
| case ISD::ATOMIC_LOAD_UMIN: |
| case ISD::ATOMIC_LOAD_UMAX: |
| return SDValue(DAG.UpdateNodeOperands(atomic.getNode(), |
| fence.getOperand(0), |
| atomic.getOperand(1), atomic.getOperand(2)), |
| atomic.getResNo()); |
| default: |
| return SDValue(); |
| } |
| } |
| |
| /// XformToShuffleWithZero - Returns a vector_shuffle if it able to transform |
| /// an AND to a vector_shuffle with the destination vector and a zero vector. |
| /// e.g. AND V, <0xffffffff, 0, 0xffffffff, 0>. ==> |
| /// vector_shuffle V, Zero, <0, 4, 2, 4> |
| SDValue DAGCombiner::XformToShuffleWithZero(SDNode *N) { |
| EVT VT = N->getValueType(0); |
| DebugLoc dl = N->getDebugLoc(); |
| SDValue LHS = N->getOperand(0); |
| SDValue RHS = N->getOperand(1); |
| if (N->getOpcode() == ISD::AND) { |
| if (RHS.getOpcode() == ISD::BITCAST) |
| RHS = RHS.getOperand(0); |
| if (RHS.getOpcode() == ISD::BUILD_VECTOR) { |
| SmallVector<int, 8> Indices; |
| unsigned NumElts = RHS.getNumOperands(); |
| for (unsigned i = 0; i != NumElts; ++i) { |
| SDValue Elt = RHS.getOperand(i); |
| if (!isa<ConstantSDNode>(Elt)) |
| return SDValue(); |
| |
| if (cast<ConstantSDNode>(Elt)->isAllOnesValue()) |
| Indices.push_back(i); |
| else if (cast<ConstantSDNode>(Elt)->isNullValue()) |
| Indices.push_back(NumElts); |
| else |
| return SDValue(); |
| } |
| |
| // Let's see if the target supports this vector_shuffle. |
| EVT RVT = RHS.getValueType(); |
| if (!TLI.isVectorClearMaskLegal(Indices, RVT)) |
| return SDValue(); |
| |
| // Return the new VECTOR_SHUFFLE node. |
| EVT EltVT = RVT.getVectorElementType(); |
| SmallVector<SDValue,8> ZeroOps(RVT.getVectorNumElements(), |
| DAG.getConstant(0, EltVT)); |
| SDValue Zero = DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), |
| RVT, &ZeroOps[0], ZeroOps.size()); |
| LHS = DAG.getNode(ISD::BITCAST, dl, RVT, LHS); |
| SDValue Shuf = DAG.getVectorShuffle(RVT, dl, LHS, Zero, &Indices[0]); |
| return DAG.getNode(ISD::BITCAST, dl, VT, Shuf); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| /// SimplifyVBinOp - Visit a binary vector operation, like ADD. |
| SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) { |
| assert(N->getValueType(0).isVector() && |
| "SimplifyVBinOp only works on vectors!"); |
| |
| SDValue LHS = N->getOperand(0); |
| SDValue RHS = N->getOperand(1); |
| SDValue Shuffle = XformToShuffleWithZero(N); |
| if (Shuffle.getNode()) return Shuffle; |
| |
| // If the LHS and RHS are BUILD_VECTOR nodes, see if we can constant fold |
| // this operation. |
| if (LHS.getOpcode() == ISD::BUILD_VECTOR && |
| RHS.getOpcode() == ISD::BUILD_VECTOR) { |
| SmallVector<SDValue, 8> Ops; |
| for (unsigned i = 0, e = LHS.getNumOperands(); i != e; ++i) { |
| SDValue LHSOp = LHS.getOperand(i); |
| SDValue RHSOp = RHS.getOperand(i); |
| // If these two elements can't be folded, bail out. |
| if ((LHSOp.getOpcode() != ISD::UNDEF && |
| LHSOp.getOpcode() != ISD::Constant && |
| LHSOp.getOpcode() != ISD::ConstantFP) || |
| (RHSOp.getOpcode() != ISD::UNDEF && |
| RHSOp.getOpcode() != ISD::Constant && |
| RHSOp.getOpcode() != ISD::ConstantFP)) |
| break; |
| |
| // Can't fold divide by zero. |
| if (N->getOpcode() == ISD::SDIV || N->getOpcode() == ISD::UDIV || |
| N->getOpcode() == ISD::FDIV) { |
| if ((RHSOp.getOpcode() == ISD::Constant && |
| cast<ConstantSDNode>(RHSOp.getNode())->isNullValue()) || |
| (RHSOp.getOpcode() == ISD::ConstantFP && |
| cast<ConstantFPSDNode>(RHSOp.getNode())->getValueAPF().isZero())) |
| break; |
| } |
| |
| EVT VT = LHSOp.getValueType(); |
| EVT RVT = RHSOp.getValueType(); |
| if (RVT != VT) { |
| // Integer BUILD_VECTOR operands may have types larger than the element |
| // size (e.g., when the element type is not legal). Prior to type |
| // legalization, the types may not match between the two BUILD_VECTORS. |
| // Truncate one of the operands to make them match. |
| if (RVT.getSizeInBits() > VT.getSizeInBits()) { |
| RHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, RHSOp); |
| } else { |
| LHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), RVT, LHSOp); |
| VT = RVT; |
| } |
| } |
| SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), VT, |
| LHSOp, RHSOp); |
| if (FoldOp.getOpcode() != ISD::UNDEF && |
| FoldOp.getOpcode() != ISD::Constant && |
| FoldOp.getOpcode() != ISD::ConstantFP) |
| break; |
| Ops.push_back(FoldOp); |
| AddToWorkList(FoldOp.getNode()); |
| } |
| |
| if (Ops.size() == LHS.getNumOperands()) |
| return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), |
| LHS.getValueType(), &Ops[0], Ops.size()); |
| } |
| |
| return SDValue(); |
| } |
| |
| /// SimplifyVUnaryOp - Visit a binary vector operation, like FABS/FNEG. |
| SDValue DAGCombiner::SimplifyVUnaryOp(SDNode *N) { |
| assert(N->getValueType(0).isVector() && |
| "SimplifyVUnaryOp only works on vectors!"); |
| |
| SDValue N0 = N->getOperand(0); |
| |
| if (N0.getOpcode() != ISD::BUILD_VECTOR) |
| return SDValue(); |
| |
| // Operand is a BUILD_VECTOR node, see if we can constant fold it. |
| SmallVector<SDValue, 8> Ops; |
| for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i) { |
| SDValue Op = N0.getOperand(i); |
| if (Op.getOpcode() != ISD::UNDEF && |
| Op.getOpcode() != ISD::ConstantFP) |
| break; |
| EVT EltVT = Op.getValueType(); |
| SDValue FoldOp = DAG.getNode(N->getOpcode(), N0.getDebugLoc(), EltVT, Op); |
| if (FoldOp.getOpcode() != ISD::UNDEF && |
| FoldOp.getOpcode() != ISD::ConstantFP) |
| break; |
| Ops.push_back(FoldOp); |
| AddToWorkList(FoldOp.getNode()); |
| } |
| |
| if (Ops.size() != N0.getNumOperands()) |
| return SDValue(); |
| |
| return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), |
| N0.getValueType(), &Ops[0], Ops.size()); |
| } |
| |
| SDValue DAGCombiner::SimplifySelect(DebugLoc DL, SDValue N0, |
| SDValue N1, SDValue N2){ |
| assert(N0.getOpcode() ==ISD::SETCC && "First argument must be a SetCC node!"); |
| |
| SDValue SCC = SimplifySelectCC(DL, N0.getOperand(0), N0.getOperand(1), N1, N2, |
| cast<CondCodeSDNode>(N0.getOperand(2))->get()); |
| |
| // If we got a simplified select_cc node back from SimplifySelectCC, then |
| // break it down into a new SETCC node, and a new SELECT node, and then return |
| // the SELECT node, since we were called with a SELECT node. |
| if (SCC.getNode()) { |
| // Check to see if we got a select_cc back (to turn into setcc/select). |
| // Otherwise, just return whatever node we got back, like fabs. |
| if (SCC.getOpcode() == ISD::SELECT_CC) { |
| SDValue SETCC = DAG.getNode(ISD::SETCC, N0.getDebugLoc(), |
| N0.getValueType(), |
| SCC.getOperand(0), SCC.getOperand(1), |
| SCC.getOperand(4)); |
| AddToWorkList(SETCC.getNode()); |
| return DAG.getNode(ISD::SELECT, SCC.getDebugLoc(), SCC.getValueType(), |
| SCC.getOperand(2), SCC.getOperand(3), SETCC); |
| } |
| |
| return SCC; |
| } |
| return SDValue(); |
| } |
| |
| /// SimplifySelectOps - Given a SELECT or a SELECT_CC node, where LHS and RHS |
| /// are the two values being selected between, see if we can simplify the |
| /// select. Callers of this should assume that TheSelect is deleted if this |
| /// returns true. As such, they should return the appropriate thing (e.g. the |
| /// node) back to the top-level of the DAG combiner loop to avoid it being |
| /// looked at. |
| bool DAGCombiner::SimplifySelectOps(SDNode *TheSelect, SDValue LHS, |
| SDValue RHS) { |
| |
| // Cannot simplify select with vector condition |
| if (TheSelect->getOperand(0).getValueType().isVector()) return false; |
| |
| // If this is a select from two identical things, try to pull the operation |
| // through the select. |
| if (LHS.getOpcode() != RHS.getOpcode() || |
| !LHS.hasOneUse() || !RHS.hasOneUse()) |
| return false; |
| |
| // If this is a load and the token chain is identical, replace the select |
| // of two loads with a load through a select of the address to load from. |
| // This triggers in things like "select bool X, 10.0, 123.0" after the FP |
| // constants have been dropped into the constant pool. |
| if (LHS.getOpcode() == ISD::LOAD) { |
| LoadSDNode *LLD = cast<LoadSDNode>(LHS); |
| LoadSDNode *RLD = cast<LoadSDNode>(RHS); |
| |
| // Token chains must be identical. |
| if (LHS.getOperand(0) != RHS.getOperand(0) || |
| // Do not let this transformation reduce the number of volatile loads. |
| LLD->isVolatile() || RLD->isVolatile() || |
| // If this is an EXTLOAD, the VT's must match. |
| LLD->getMemoryVT() != RLD->getMemoryVT() || |
| // If this is an EXTLOAD, the kind of extension must match. |
| (LLD->getExtensionType() != RLD->getExtensionType() && |
| // The only exception is if one of the extensions is anyext. |
| LLD->getExtensionType() != ISD::EXTLOAD && |
| RLD->getExtensionType() != ISD::EXTLOAD) || |
| // FIXME: this discards src value information. This is |
| // over-conservative. It would be beneficial to be able to remember |
| // both potential memory locations. Since we are discarding |
| // src value info, don't do the transformation if the memory |
| // locations are not in the default address space. |
| LLD->getPointerInfo().getAddrSpace() != 0 || |
| RLD->getPointerInfo().getAddrSpace() != 0 || |
| !TLI.isOperationLegalOrCustom(TheSelect->getOpcode(), |
| LLD->getBasePtr().getValueType())) |
| return false; |
| |
| // Check that the select condition doesn't reach either load. If so, |
| // folding this will induce a cycle into the DAG. If not, this is safe to |
| // xform, so create a select of the addresses. |
| SDValue Addr; |
| if (TheSelect->getOpcode() == ISD::SELECT) { |
| SDNode *CondNode = TheSelect->getOperand(0).getNode(); |
| if ((LLD->hasAnyUseOfValue(1) && LLD->isPredecessorOf(CondNode)) || |
| (RLD->hasAnyUseOfValue(1) && RLD->isPredecessorOf(CondNode))) |
| return false; |
| // The loads must not depend on one another. |
| if (LLD->isPredecessorOf(RLD) || |
| RLD->isPredecessorOf(LLD)) |
| return false; |
| Addr = DAG.getNode(ISD::SELECT, TheSelect->getDebugLoc(), |
| LLD->getBasePtr().getValueType(), |
| TheSelect->getOperand(0), LLD->getBasePtr(), |
| RLD->getBasePtr()); |
| } else { // Otherwise SELECT_CC |
| SDNode *CondLHS = TheSelect->getOperand(0).getNode(); |
| SDNode *CondRHS = TheSelect->getOperand(1).getNode(); |
| |
| if ((LLD->hasAnyUseOfValue(1) && |
| (LLD->isPredecessorOf(CondLHS) || LLD->isPredecessorOf(CondRHS))) || |
| (RLD->hasAnyUseOfValue(1) && |
| (RLD->isPredecessorOf(CondLHS) || RLD->isPredecessorOf(CondRHS)))) |
| return false; |
| |
| Addr = DAG.getNode(ISD::SELECT_CC, TheSelect->getDebugLoc(), |
| LLD->getBasePtr().getValueType(), |
| TheSelect->getOperand(0), |
| TheSelect->getOperand(1), |
| LLD->getBasePtr(), RLD->getBasePtr(), |
| TheSelect->getOperand(4)); |
| } |
| |
| SDValue Load; |
| if (LLD->getExtensionType() == ISD::NON_EXTLOAD) { |
| Load = DAG.getLoad(TheSelect->getValueType(0), |
| TheSelect->getDebugLoc(), |
| // FIXME: Discards pointer info. |
| LLD->getChain(), Addr, MachinePointerInfo(), |
| LLD->isVolatile(), LLD->isNonTemporal(), |
| LLD->isInvariant(), LLD->getAlignment()); |
| } else { |
| Load = DAG.getExtLoad(LLD->getExtensionType() == ISD::EXTLOAD ? |
| RLD->getExtensionType() : LLD->getExtensionType(), |
| TheSelect->getDebugLoc(), |
| TheSelect->getValueType(0), |
| // FIXME: Discards pointer info. |
| LLD->getChain(), Addr, MachinePointerInfo(), |
| LLD->getMemoryVT(), LLD->isVolatile(), |
| LLD->isNonTemporal(), LLD->getAlignment()); |
| } |
| |
| // Users of the select now use the result of the load. |
| CombineTo(TheSelect, Load); |
| |
| // Users of the old loads now use the new load's chain. We know the |
| // old-load value is dead now. |
| CombineTo(LHS.getNode(), Load.getValue(0), Load.getValue(1)); |
| CombineTo(RHS.getNode(), Load.getValue(0), Load.getValue(1)); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /// SimplifySelectCC - Simplify an expression of the form (N0 cond N1) ? N2 : N3 |
| /// where 'cond' is the comparison specified by CC. |
| SDValue DAGCombiner::SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1, |
| SDValue N2, SDValue N3, |
| ISD::CondCode CC, bool NotExtCompare) { |
| // (x ? y : y) -> y. |
| if (N2 == N3) return N2; |
| |
| EVT VT = N2.getValueType(); |
| ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode()); |
| ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.getNode()); |
| ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.getNode()); |
| |
| // Determine if the condition we're dealing with is constant |
| SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()), |
| N0, N1, CC, DL, false); |
| if (SCC.getNode()) AddToWorkList(SCC.getNode()); |
| ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode()); |
| |
| // fold select_cc true, x, y -> x |
| if (SCCC && !SCCC->isNullValue()) |
| return N2; |
| // fold select_cc false, x, y -> y |
| if (SCCC && SCCC->isNullValue()) |
| return N3; |
| |
| // Check to see if we can simplify the select into an fabs node |
| if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N1)) { |
| // Allow either -0.0 or 0.0 |
| if (CFP->getValueAPF().isZero()) { |
| // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs |
| if ((CC == ISD::SETGE || CC == ISD::SETGT) && |
| N0 == N2 && N3.getOpcode() == ISD::FNEG && |
| N2 == N3.getOperand(0)) |
| return DAG.getNode(ISD::FABS, DL, VT, N0); |
| |
| // select (setl[te] X, +/-0.0), fneg(X), X -> fabs |
| if ((CC == ISD::SETLT || CC == ISD::SETLE) && |
| N0 == N3 && N2.getOpcode() == ISD::FNEG && |
| N2.getOperand(0) == N3) |
| return DAG.getNode(ISD::FABS, DL, VT, N3); |
| } |
| } |
| |
| // Turn "(a cond b) ? 1.0f : 2.0f" into "load (tmp + ((a cond b) ? 0 : 4)" |
| // where "tmp" is a constant pool entry containing an array with 1.0 and 2.0 |
| // in it. This is a win when the constant is not otherwise available because |
| // it replaces two constant pool loads with one. We only do this if the FP |
| // type is known to be legal, because if it isn't, then we are before legalize |
| // types an we want the other legalization to happen first (e.g. to avoid |
| // messing with soft float) and if the ConstantFP is not legal, because if |
| // it is legal, we may not need to store the FP constant in a constant pool. |
| if (ConstantFPSDNode *TV = dyn_cast<ConstantFPSDNode>(N2)) |
| if (ConstantFPSDNode *FV = dyn_cast<ConstantFPSDNode>(N3)) { |
| if (TLI.isTypeLegal(N2.getValueType()) && |
| (TLI.getOperationAction(ISD::ConstantFP, N2.getValueType()) != |
| TargetLowering::Legal) && |
| // If both constants have multiple uses, then we won't need to do an |
| // extra load, they are likely around in registers for other users. |
| (TV->hasOneUse() || FV->hasOneUse())) { |
| Constant *Elts[] = { |
| const_cast<ConstantFP*>(FV->getConstantFPValue()), |
| const_cast<ConstantFP*>(TV->getConstantFPValue()) |
| }; |
| Type *FPTy = Elts[0]->getType(); |
| const DataLayout &TD = *TLI.getDataLayout(); |
| |
| // Create a ConstantArray of the two constants. |
| Constant *CA = ConstantArray::get(ArrayType::get(FPTy, 2), Elts); |
| SDValue CPIdx = DAG.getConstantPool(CA, TLI.getPointerTy(), |
| TD.getPrefTypeAlignment(FPTy)); |
| unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment(); |
| |
| // Get the offsets to the 0 and 1 element of the array so that we can |
| // select between them. |
| SDValue Zero = DAG.getIntPtrConstant(0); |
| unsigned EltSize = (unsigned)TD.getTypeAllocSize(Elts[0]->getType()); |
| SDValue One = DAG.getIntPtrConstant(EltSize); |
| |
| SDValue Cond = DAG.getSetCC(DL, |
| TLI.getSetCCResultType(N0.getValueType()), |
| N0, N1, CC); |
| AddToWorkList(Cond.getNode()); |
| SDValue CstOffset = DAG.getNode(ISD::SELECT, DL, Zero.getValueType(), |
| Cond, One, Zero); |
| AddToWorkList(CstOffset.getNode()); |
| CPIdx = DAG.getNode(ISD::ADD, DL, TLI.getPointerTy(), CPIdx, |
| CstOffset); |
| AddToWorkList(CPIdx.getNode()); |
| return DAG.getLoad(TV->getValueType(0), DL, DAG.getEntryNode(), CPIdx, |
| MachinePointerInfo::getConstantPool(), false, |
| false, false, Alignment); |
| |
| } |
| } |
| |
| // Check to see if we can perform the "gzip trick", transforming |
| // (select_cc setlt X, 0, A, 0) -> (and (sra X, (sub size(X), 1), A) |
| if (N1C && N3C && N3C->isNullValue() && CC == ISD::SETLT && |
| (N1C->isNullValue() || // (a < 0) ? b : 0 |
| (N1C->getAPIntValue() == 1 && N0 == N2))) { // (a < 1) ? a : 0 |
| EVT XType = N0.getValueType(); |
| EVT AType = N2.getValueType(); |
| if (XType.bitsGE(AType)) { |
| // and (sra X, size(X)-1, A) -> "and (srl X, C2), A" iff A is a |
| // single-bit constant. |
| if (N2C && ((N2C->getAPIntValue() & (N2C->getAPIntValue()-1)) == 0)) { |
| unsigned ShCtV = N2C->getAPIntValue().logBase2(); |
| ShCtV = XType.getSizeInBits()-ShCtV-1; |
| SDValue ShCt = DAG.getConstant(ShCtV, |
| getShiftAmountTy(N0.getValueType())); |
| SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), |
| XType, N0, ShCt); |
| AddToWorkList(Shift.getNode()); |
| |
| if (XType.bitsGT(AType)) { |
| Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift); |
| AddToWorkList(Shift.getNode()); |
| } |
| |
| return DAG.getNode(ISD::AND, DL, AType, Shift, N2); |
| } |
| |
| SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(), |
| XType, N0, |
| DAG.getConstant(XType.getSizeInBits()-1, |
| getShiftAmountTy(N0.getValueType()))); |
| AddToWorkList(Shift.getNode()); |
| |
| if (XType.bitsGT(AType)) { |
| Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift); |
| AddToWorkList(Shift.getNode()); |
| } |
| |
| return DAG.getNode(ISD::AND, DL, AType, Shift, N2); |
| } |
| } |
| |
| // fold (select_cc seteq (and x, y), 0, 0, A) -> (and (shr (shl x)) A) |
| // where y is has a single bit set. |
| // A plaintext description would be, we can turn the SELECT_CC into an AND |
| // when the condition can be materialized as an all-ones register. Any |
| // single bit-test can be materialized as an all-ones register with |
| // shift-left and shift-right-arith. |
| if (CC == ISD::SETEQ && N0->getOpcode() == ISD::AND && |
| N0->getValueType(0) == VT && |
| N1C && N1C->isNullValue() && |
| N2C && N2C->isNullValue()) { |
| SDValue AndLHS = N0->getOperand(0); |
| ConstantSDNode *ConstAndRHS = dyn_cast<ConstantSDNode>(N0->getOperand(1)); |
| if (ConstAndRHS && ConstAndRHS->getAPIntValue().countPopulation() == 1) { |
| // Shift the tested bit over the sign bit. |
| APInt AndMask = ConstAndRHS->getAPIntValue(); |
| SDValue ShlAmt = |
| DAG.getConstant(AndMask.countLeadingZeros(), |
| getShiftAmountTy(AndLHS.getValueType())); |
| SDValue Shl = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT, AndLHS, ShlAmt); |
| |
| // Now arithmetic right shift it all the way over, so the result is either |
| // all-ones, or zero. |
| SDValue ShrAmt = |
| DAG.getConstant(AndMask.getBitWidth()-1, |
| getShiftAmountTy(Shl.getValueType())); |
| SDValue Shr = DAG.getNode(ISD::SRA, N0.getDebugLoc(), VT, Shl, ShrAmt); |
| |
| return DAG.getNode(ISD::AND, DL, VT, Shr, N3); |
| } |
| } |
| |
| // fold select C, 16, 0 -> shl C, 4 |
| if (N2C && N3C && N3C->isNullValue() && N2C->getAPIntValue().isPowerOf2() && |
| TLI.getBooleanContents(N0.getValueType().isVector()) == |
| TargetLowering::ZeroOrOneBooleanContent) { |
| |
| // If the caller doesn't want us to simplify this into a zext of a compare, |
| // don't do it. |
| if (NotExtCompare && N2C->getAPIntValue() == 1) |
| return SDValue(); |
| |
| // Get a SetCC of the condition |
| // NOTE: Don't create a SETCC if it's not legal on this target. |
| if (!LegalOperations || |
| TLI.isOperationLegal(ISD::SETCC, |
| LegalTypes ? TLI.getSetCCResultType(N0.getValueType()) : MVT::i1)) { |
| SDValue Temp, SCC; |
| // cast from setcc result type to select result type |
| if (LegalTypes) { |
| SCC = DAG.getSetCC(DL, TLI.getSetCCResultType(N0.getValueType()), |
| N0, N1, CC); |
| if (N2.getValueType().bitsLT(SCC.getValueType())) |
| Temp = DAG.getZeroExtendInReg(SCC, N2.getDebugLoc(), |
| N2.getValueType()); |
| else |
| Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(), |
| N2.getValueType(), SCC); |
| } else { |
| SCC = DAG.getSetCC(N0.getDebugLoc(), MVT::i1, N0, N1, CC); |
| Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(), |
| N2.getValueType(), SCC); |
| } |
| |
| AddToWorkList(SCC.getNode()); |
| AddToWorkList(Temp.getNode()); |
| |
| if (N2C->getAPIntValue() == 1) |
| return Temp; |
| |
| // shl setcc result by log2 n2c |
| return DAG.getNode(ISD::SHL, DL, N2.getValueType(), Temp, |
| DAG.getConstant(N2C->getAPIntValue().logBase2(), |
| getShiftAmountTy(Temp.getValueType()))); |
| } |
| } |
| |
| // Check to see if this is the equivalent of setcc |
| // FIXME: Turn all of these into setcc if setcc if setcc is legal |
| // otherwise, go ahead with the folds. |
| if (0 && N3C && N3C->isNullValue() && N2C && (N2C->getAPIntValue() == 1ULL)) { |
| EVT XType = N0.getValueType(); |
| if (!LegalOperations || |
| TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(XType))) { |
| SDValue Res = DAG.getSetCC(DL, TLI.getSetCCResultType(XType), N0, N1, CC); |
| if (Res.getValueType() != VT) |
| Res = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, Res); |
| return Res; |
| } |
| |
| // fold (seteq X, 0) -> (srl (ctlz X, log2(size(X)))) |
| if (N1C && N1C->isNullValue() && CC == ISD::SETEQ && |
| (!LegalOperations || |
| TLI.isOperationLegal(ISD::CTLZ, XType))) { |
| SDValue Ctlz = DAG.getNode(ISD::CTLZ, N0.getDebugLoc(), XType, N0); |
| return DAG.getNode(ISD::SRL, DL, XType, Ctlz, |
| DAG.getConstant(Log2_32(XType.getSizeInBits()), |
| getShiftAmountTy(Ctlz.getValueType()))); |
| } |
| // fold (setgt X, 0) -> (srl (and (-X, ~X), size(X)-1)) |
| if (N1C && N1C->isNullValue() && CC == ISD::SETGT) { |
| SDValue NegN0 = DAG.getNode(ISD::SUB, N0.getDebugLoc(), |
| XType, DAG.getConstant(0, XType), N0); |
| SDValue NotN0 = DAG.getNOT(N0.getDebugLoc(), N0, XType); |
| return DAG.getNode(ISD::SRL, DL, XType, |
| DAG.getNode(ISD::AND, DL, XType, NegN0, NotN0), |
| DAG.getConstant(XType.getSizeInBits()-1, |
| getShiftAmountTy(XType))); |
| } |
| // fold (setgt X, -1) -> (xor (srl (X, size(X)-1), 1)) |
| if (N1C && N1C->isAllOnesValue() && CC == ISD::SETGT) { |
| SDValue Sign = DAG.getNode(ISD::SRL, N0.getDebugLoc(), XType, N0, |
| DAG.getConstant(XType.getSizeInBits()-1, |
| getShiftAmountTy(N0.getValueType()))); |
| return DAG.getNode(ISD::XOR, DL, XType, Sign, DAG.getConstant(1, XType)); |
| } |
| } |
| |
| // Check to see if this is an integer abs. |
| // select_cc setg[te] X, 0, X, -X -> |
| // select_cc setgt X, -1, X, -X -> |
| // select_cc setl[te] X, 0, -X, X -> |
| // select_cc setlt X, 1, -X, X -> |
| // Y = sra (X, size(X)-1); xor (add (X, Y), Y) |
| if (N1C) { |
| ConstantSDNode *SubC = NULL; |
| if (((N1C->isNullValue() && (CC == ISD::SETGT || CC == ISD::SETGE)) || |
| (N1C->isAllOnesValue() && CC == ISD::SETGT)) && |
| N0 == N2 && N3.getOpcode() == ISD::SUB && N0 == N3.getOperand(1)) |
| SubC = dyn_cast<ConstantSDNode>(N3.getOperand(0)); |
| else if (((N1C->isNullValue() && (CC == ISD::SETLT || CC == ISD::SETLE)) || |
| (N1C->isOne() && CC == ISD::SETLT)) && |
| N0 == N3 && N2.getOpcode() == ISD::SUB && N0 == N2.getOperand(1)) |
| SubC = dyn_cast<ConstantSDNode>(N2.getOperand(0)); |
| |
| EVT XType = N0.getValueType(); |
| if (SubC && SubC->isNullValue() && XType.isInteger()) { |
| SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(), XType, |
| N0, |
| DAG.getConstant(XType.getSizeInBits()-1, |
| getShiftAmountTy(N0.getValueType()))); |
| SDValue Add = DAG.getNode(ISD::ADD, N0.getDebugLoc(), |
| XType, N0, Shift); |
| AddToWorkList(Shift.getNode()); |
| AddToWorkList(Add.getNode()); |
| return DAG.getNode(ISD::XOR, DL, XType, Add, Shift); |
| } |
| } |
| |
| return SDValue(); |
| } |
| |
| /// SimplifySetCC - This is a stub for TargetLowering::SimplifySetCC. |
| SDValue DAGCombiner::SimplifySetCC(EVT VT, SDValue N0, |
| SDValue N1, ISD::CondCode Cond, |
| DebugLoc DL, bool foldBooleans) { |
| TargetLowering::DAGCombinerInfo |
| DagCombineInfo(DAG, Level, false, this); |
| return TLI.SimplifySetCC(VT, N0, N1, Cond, foldBooleans, DagCombineInfo, DL); |
| } |
| |
| /// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant, |
| /// return a DAG expression to select that will generate the same value by |
| /// multiplying by a magic number. See: |
| /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html> |
| SDValue DAGCombiner::BuildSDIV(SDNode *N) { |
| std::vector<SDNode*> Built; |
| SDValue S = TLI.BuildSDIV(N, DAG, LegalOperations, &Built); |
| |
| for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end(); |
| ii != ee; ++ii) |
| AddToWorkList(*ii); |
| return S; |
| } |
| |
| /// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant, |
| /// return a DAG expression to select that will generate the same value by |
| /// multiplying by a magic number. See: |
| /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html> |
| SDValue DAGCombiner::BuildUDIV(SDNode *N) { |
| std::vector<SDNode*> Built; |
| SDValue S = TLI.BuildUDIV(N, DAG, LegalOperations, &Built); |
| |
| for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end(); |
| ii != ee; ++ii) |
| AddToWorkList(*ii); |
| return S; |
| } |
| |
| /// FindBaseOffset - Return true if base is a frame index, which is known not |
| // to alias with anything but itself. Provides base object and offset as |
| // results. |
| static bool FindBaseOffset(SDValue Ptr, SDValue &Base, int64_t &Offset, |
| const GlobalValue *&GV, const void *&CV) { |
| // Assume it is a primitive operation. |
| Base = Ptr; Offset = 0; GV = 0; CV = 0; |
| |
| // If it's an adding a simple constant then integrate the offset. |
| if (Base.getOpcode() == ISD::ADD) { |
| if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Base.getOperand(1))) { |
| Base = Base.getOperand(0); |
| Offset += C->getZExtValue(); |
| } |
| } |
| |
| // Return the underlying GlobalValue, and update the Offset. Return false |
| // for GlobalAddressSDNode since the same GlobalAddress may be represented |
| // by multiple nodes with different offsets. |
| if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Base)) { |
| GV = G->getGlobal(); |
| Offset += G->getOffset(); |
| return false; |
| } |
| |
| // Return the underlying Constant value, and update the Offset. Return false |
| // for ConstantSDNodes since the same constant pool entry may be represented |
| // by multiple nodes with different offsets. |
| if (ConstantPoolSDNode *C = dyn_cast<ConstantPoolSDNode>(Base)) { |
| CV = C->isMachineConstantPoolEntry() ? (const void *)C->getMachineCPVal() |
| : (const void *)C->getConstVal(); |
| Offset += C->getOffset(); |
| return false; |
| } |
| // If it's any of the following then it can't alias with anything but itself. |
| return isa<FrameIndexSDNode>(Base); |
| } |
| |
| /// isAlias - Return true if there is any possibility that the two addresses |
| /// overlap. |
| bool DAGCombiner::isAlias(SDValue Ptr1, int64_t Size1, |
| const Value *SrcValue1, int SrcValueOffset1, |
| unsigned SrcValueAlign1, |
| const MDNode *TBAAInfo1, |
| SDValue Ptr2, int64_t Size2, |
| const Value *SrcValue2, int SrcValueOffset2, |
| unsigned SrcValueAlign2, |
| const MDNode *TBAAInfo2) const { |
| // If they are the same then they must be aliases. |
| if (Ptr1 == Ptr2) return true; |
| |
| // Gather base node and offset information. |
| SDValue Base1, Base2; |
| int64_t Offset1, Offset2; |
| const GlobalValue *GV1, *GV2; |
| const void *CV1, *CV2; |
| bool isFrameIndex1 = FindBaseOffset(Ptr1, Base1, Offset1, GV1, CV1); |
| bool isFrameIndex2 = FindBaseOffset(Ptr2, Base2, Offset2, GV2, CV2); |
| |
| // If they have a same base address then check to see if they overlap. |
| if (Base1 == Base2 || (GV1 && (GV1 == GV2)) || (CV1 && (CV1 == CV2))) |
| return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1); |
| |
| // It is possible for different frame indices to alias each other, mostly |
| // when tail call optimization reuses return address slots for arguments. |
| // To catch this case, look up the actual index of frame indices to compute |
| // the real alias relationship. |
| if (isFrameIndex1 && isFrameIndex2) { |
| MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo(); |
| Offset1 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base1)->getIndex()); |
| Offset2 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base2)->getIndex()); |
| return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1); |
| } |
| |
| // Otherwise, if we know what the bases are, and they aren't identical, then |
| // we know they cannot alias. |
| if ((isFrameIndex1 || CV1 || GV1) && (isFrameIndex2 || CV2 || GV2)) |
| return false; |
| |
| // If we know required SrcValue1 and SrcValue2 have relatively large alignment |
| // compared to the size and offset of the access, we may be able to prove they |
| // do not alias. This check is conservative for now to catch cases created by |
| // splitting vector types. |
| if ((SrcValueAlign1 == SrcValueAlign2) && |
| (SrcValueOffset1 != SrcValueOffset2) && |
| (Size1 == Size2) && (SrcValueAlign1 > Size1)) { |
| int64_t OffAlign1 = SrcValueOffset1 % SrcValueAlign1; |
| int64_t OffAlign2 = SrcValueOffset2 % SrcValueAlign1; |
| |
| // There is no overlap between these relatively aligned accesses of similar |
| // size, return no alias. |
| if ((OffAlign1 + Size1) <= OffAlign2 || (OffAlign2 + Size2) <= OffAlign1) |
| return false; |
| } |
| |
| if (CombinerGlobalAA) { |
| // Use alias analysis information. |
| int64_t MinOffset = std::min(SrcValueOffset1, SrcValueOffset2); |
| int64_t Overlap1 = Size1 + SrcValueOffset1 - MinOffset; |
| int64_t Overlap2 = Size2 + SrcValueOffset2 - MinOffset; |
| AliasAnalysis::AliasResult AAResult = |
| AA.alias(AliasAnalysis::Location(SrcValue1, Overlap1, TBAAInfo1), |
| AliasAnalysis::Location(SrcValue2, Overlap2, TBAAInfo2)); |
| if (AAResult == AliasAnalysis::NoAlias) |
| return false; |
| } |
| |
| // Otherwise we have to assume they alias. |
| return true; |
| } |
| |
| bool DAGCombiner::isAlias(LSBaseSDNode *Op0, LSBaseSDNode *Op1) { |
| SDValue Ptr0, Ptr1; |
| int64_t Size0, Size1; |
| const Value *SrcValue0, *SrcValue1; |
| int SrcValueOffset0, SrcValueOffset1; |
| unsigned SrcValueAlign0, SrcValueAlign1; |
| const MDNode *SrcTBAAInfo0, *SrcTBAAInfo1; |
| FindAliasInfo(Op0, Ptr0, Size0, SrcValue0, SrcValueOffset0, |
| SrcValueAlign0, SrcTBAAInfo0); |
| FindAliasInfo(Op1, Ptr1, Size1, SrcValue1, SrcValueOffset1, |
| SrcValueAlign1, SrcTBAAInfo1); |
| return isAlias(Ptr0, Size0, SrcValue0, SrcValueOffset0, |
| SrcValueAlign0, SrcTBAAInfo0, |
| Ptr1, Size1, SrcValue1, SrcValueOffset1, |
| SrcValueAlign1, SrcTBAAInfo1); |
| } |
| |
| /// FindAliasInfo - Extracts the relevant alias information from the memory |
| /// node. Returns true if the operand was a load. |
| bool DAGCombiner::FindAliasInfo(SDNode *N, |
| SDValue &Ptr, int64_t &Size, |
| const Value *&SrcValue, |
| int &SrcValueOffset, |
| unsigned &SrcValueAlign, |
| const MDNode *&TBAAInfo) const { |
| LSBaseSDNode *LS = cast<LSBaseSDNode>(N); |
| |
| Ptr = LS->getBasePtr(); |
| Size = LS->getMemoryVT().getSizeInBits() >> 3; |
| SrcValue = LS->getSrcValue(); |
| SrcValueOffset = LS->getSrcValueOffset(); |
| SrcValueAlign = LS->getOriginalAlignment(); |
| TBAAInfo = LS->getTBAAInfo(); |
| return isa<LoadSDNode>(LS); |
| } |
| |
| /// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes, |
| /// looking for aliasing nodes and adding them to the Aliases vector. |
| void DAGCombiner::GatherAllAliases(SDNode *N, SDValue OriginalChain, |
| SmallVector<SDValue, 8> &Aliases) { |
| SmallVector<SDValue, 8> Chains; // List of chains to visit. |
| SmallPtrSet<SDNode *, 16> Visited; // Visited node set. |
| |
| // Get alias information for node. |
| SDValue Ptr; |
| int64_t Size; |
| const Value *SrcValue; |
| int SrcValueOffset; |
| unsigned SrcValueAlign; |
| const MDNode *SrcTBAAInfo; |
| bool IsLoad = FindAliasInfo(N, Ptr, Size, SrcValue, SrcValueOffset, |
| SrcValueAlign, SrcTBAAInfo); |
| |
| // Starting off. |
| Chains.push_back(OriginalChain); |
| unsigned Depth = 0; |
| |
| // Look at each chain and determine if it is an alias. If so, add it to the |
| // aliases list. If not, then continue up the chain looking for the next |
| // candidate. |
| while (!Chains.empty()) { |
| SDValue Chain = Chains.back(); |
| Chains.pop_back(); |
| |
| // For TokenFactor nodes, look at each operand and only continue up the |
| // chain until we find two aliases. If we've seen two aliases, assume we'll |
| // find more and revert to original chain since the xform is unlikely to be |
| // profitable. |
| // |
| // FIXME: The depth check could be made to return the last non-aliasing |
| // chain we found before we hit a tokenfactor rather than the original |
| // chain. |
| if (Depth > 6 || Aliases.size() == 2) { |
| Aliases.clear(); |
| Aliases.push_back(OriginalChain); |
| break; |
| } |
| |
| // Don't bother if we've been before. |
| if (!Visited.insert(Chain.getNode())) |
| continue; |
| |
| switch (Chain.getOpcode()) { |
| case ISD::EntryToken: |
| // Entry token is ideal chain operand, but handled in FindBetterChain. |
| break; |
| |
| case ISD::LOAD: |
| case ISD::STORE: { |
| // Get alias information for Chain. |
| SDValue OpPtr; |
| int64_t OpSize; |
| const Value *OpSrcValue; |
| int OpSrcValueOffset; |
| unsigned OpSrcValueAlign; |
| const MDNode *OpSrcTBAAInfo; |
| bool IsOpLoad = FindAliasInfo(Chain.getNode(), OpPtr, OpSize, |
| OpSrcValue, OpSrcValueOffset, |
| OpSrcValueAlign, |
| OpSrcTBAAInfo); |
| |
| // If chain is alias then stop here. |
| if (!(IsLoad && IsOpLoad) && |
| isAlias(Ptr, Size, SrcValue, SrcValueOffset, SrcValueAlign, |
| SrcTBAAInfo, |
| OpPtr, OpSize, OpSrcValue, OpSrcValueOffset, |
| OpSrcValueAlign, OpSrcTBAAInfo)) { |
| Aliases.push_back(Chain); |
| } else { |
| // Look further up the chain. |
| Chains.push_back(Chain.getOperand(0)); |
| ++Depth; |
| } |
| break; |
| } |
| |
| case ISD::TokenFactor: |
| // We have to check each of the operands of the token factor for "small" |
| // token factors, so we queue them up. Adding the operands to the queue |
| // (stack) in reverse order maintains the original order and increases the |
| // likelihood that getNode will find a matching token factor (CSE.) |
| if (Chain.getNumOperands() > 16) { |
| Aliases.push_back(Chain); |
| break; |
| } |
| for (unsigned n = Chain.getNumOperands(); n;) |
| Chains.push_back(Chain.getOperand(--n)); |
| ++Depth; |
| break; |
| |
| default: |
| // For all other instructions we will just have to take what we can get. |
| Aliases.push_back(Chain); |
| break; |
| } |
| } |
| } |
| |
| /// FindBetterChain - Walk up chain skipping non-aliasing memory nodes, looking |
| /// for a better chain (aliasing node.) |
| SDValue DAGCombiner::FindBetterChain(SDNode *N, SDValue OldChain) { |
| SmallVector<SDValue, 8> Aliases; // Ops for replacing token factor. |
| |
| // Accumulate all the aliases to this node. |
| GatherAllAliases(N, OldChain, Aliases); |
| |
| // If no operands then chain to entry token. |
| if (Aliases.size() == 0) |
| return DAG.getEntryNode(); |
| |
| // If a single operand then chain to it. We don't need to revisit it. |
| if (Aliases.size() == 1) |
| return Aliases[0]; |
| |
| // Construct a custom tailored token factor. |
| return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other, |
| &Aliases[0], Aliases.size()); |
| } |
| |
| // SelectionDAG::Combine - This is the entry point for the file. |
| // |
| void SelectionDAG::Combine(CombineLevel Level, AliasAnalysis &AA, |
| CodeGenOpt::Level OptLevel) { |
| /// run - This is the main entry point to this class. |
| /// |
| DAGCombiner(*this, AA, OptLevel).Run(Level); |
| } |