| //===- X86ISelDAGToDAG.cpp - A DAG pattern matching inst selector for X86 -===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines a DAG pattern matching instruction selector for X86, |
| // converting from a legalized dag to a X86 dag. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "x86-isel" |
| #include "X86.h" |
| #include "X86InstrBuilder.h" |
| #include "X86ISelLowering.h" |
| #include "X86MachineFunctionInfo.h" |
| #include "X86RegisterInfo.h" |
| #include "X86Subtarget.h" |
| #include "X86TargetMachine.h" |
| #include "llvm/GlobalValue.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/Intrinsics.h" |
| #include "llvm/Support/CFG.h" |
| #include "llvm/Type.h" |
| #include "llvm/CodeGen/MachineConstantPool.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineRegisterInfo.h" |
| #include "llvm/CodeGen/SelectionDAGISel.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include "llvm/Target/TargetOptions.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/MathExtras.h" |
| #include "llvm/Support/Streams.h" |
| #include "llvm/ADT/SmallPtrSet.h" |
| #include "llvm/ADT/Statistic.h" |
| using namespace llvm; |
| |
| STATISTIC(NumFPKill , "Number of FP_REG_KILL instructions added"); |
| STATISTIC(NumLoadMoved, "Number of loads moved below TokenFactor"); |
| |
| //===----------------------------------------------------------------------===// |
| // Pattern Matcher Implementation |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| /// X86ISelAddressMode - This corresponds to X86AddressMode, but uses |
| /// SDValue's instead of register numbers for the leaves of the matched |
| /// tree. |
| struct X86ISelAddressMode { |
| enum { |
| RegBase, |
| FrameIndexBase |
| } BaseType; |
| |
| struct { // This is really a union, discriminated by BaseType! |
| SDValue Reg; |
| int FrameIndex; |
| } Base; |
| |
| bool isRIPRel; // RIP as base? |
| unsigned Scale; |
| SDValue IndexReg; |
| unsigned Disp; |
| GlobalValue *GV; |
| Constant *CP; |
| const char *ES; |
| int JT; |
| unsigned Align; // CP alignment. |
| |
| X86ISelAddressMode() |
| : BaseType(RegBase), isRIPRel(false), Scale(1), IndexReg(), Disp(0), |
| GV(0), CP(0), ES(0), JT(-1), Align(0) { |
| } |
| void dump() { |
| cerr << "X86ISelAddressMode " << this << "\n"; |
| cerr << "Base.Reg "; |
| if (Base.Reg.getNode() != 0) Base.Reg.getNode()->dump(); |
| else cerr << "nul"; |
| cerr << " Base.FrameIndex " << Base.FrameIndex << "\n"; |
| cerr << "isRIPRel " << isRIPRel << " Scale" << Scale << "\n"; |
| cerr << "IndexReg "; |
| if (IndexReg.getNode() != 0) IndexReg.getNode()->dump(); |
| else cerr << "nul"; |
| cerr << " Disp " << Disp << "\n"; |
| cerr << "GV "; if (GV) GV->dump(); |
| else cerr << "nul"; |
| cerr << " CP "; if (CP) CP->dump(); |
| else cerr << "nul"; |
| cerr << "\n"; |
| cerr << "ES "; if (ES) cerr << ES; else cerr << "nul"; |
| cerr << " JT" << JT << " Align" << Align << "\n"; |
| } |
| }; |
| } |
| |
| namespace { |
| //===--------------------------------------------------------------------===// |
| /// ISel - X86 specific code to select X86 machine instructions for |
| /// SelectionDAG operations. |
| /// |
| class VISIBILITY_HIDDEN X86DAGToDAGISel : public SelectionDAGISel { |
| /// TM - Keep a reference to X86TargetMachine. |
| /// |
| X86TargetMachine &TM; |
| |
| /// X86Lowering - This object fully describes how to lower LLVM code to an |
| /// X86-specific SelectionDAG. |
| X86TargetLowering &X86Lowering; |
| |
| /// Subtarget - Keep a pointer to the X86Subtarget around so that we can |
| /// make the right decision when generating code for different targets. |
| const X86Subtarget *Subtarget; |
| |
| /// CurBB - Current BB being isel'd. |
| /// |
| MachineBasicBlock *CurBB; |
| |
| /// OptForSize - If true, selector should try to optimize for code size |
| /// instead of performance. |
| bool OptForSize; |
| |
| public: |
| X86DAGToDAGISel(X86TargetMachine &tm, bool fast) |
| : SelectionDAGISel(*tm.getTargetLowering(), fast), |
| TM(tm), X86Lowering(*TM.getTargetLowering()), |
| Subtarget(&TM.getSubtarget<X86Subtarget>()), |
| OptForSize(false) {} |
| |
| virtual const char *getPassName() const { |
| return "X86 DAG->DAG Instruction Selection"; |
| } |
| |
| /// InstructionSelect - This callback is invoked by |
| /// SelectionDAGISel when it has created a SelectionDAG for us to codegen. |
| virtual void InstructionSelect(); |
| |
| /// InstructionSelectPostProcessing - Post processing of selected and |
| /// scheduled basic blocks. |
| virtual void InstructionSelectPostProcessing(); |
| |
| virtual void EmitFunctionEntryCode(Function &Fn, MachineFunction &MF); |
| |
| virtual bool CanBeFoldedBy(SDNode *N, SDNode *U, SDNode *Root) const; |
| |
| // Include the pieces autogenerated from the target description. |
| #include "X86GenDAGISel.inc" |
| |
| private: |
| SDNode *Select(SDValue N); |
| SDNode *SelectAtomic64(SDNode *Node, unsigned Opc); |
| |
| bool MatchAddress(SDValue N, X86ISelAddressMode &AM, |
| bool isRoot = true, unsigned Depth = 0); |
| bool MatchAddressBase(SDValue N, X86ISelAddressMode &AM, |
| bool isRoot, unsigned Depth); |
| bool SelectAddr(SDValue Op, SDValue N, SDValue &Base, |
| SDValue &Scale, SDValue &Index, SDValue &Disp); |
| bool SelectLEAAddr(SDValue Op, SDValue N, SDValue &Base, |
| SDValue &Scale, SDValue &Index, SDValue &Disp); |
| bool SelectScalarSSELoad(SDValue Op, SDValue Pred, |
| SDValue N, SDValue &Base, SDValue &Scale, |
| SDValue &Index, SDValue &Disp, |
| SDValue &InChain, SDValue &OutChain); |
| bool TryFoldLoad(SDValue P, SDValue N, |
| SDValue &Base, SDValue &Scale, |
| SDValue &Index, SDValue &Disp); |
| void PreprocessForRMW(); |
| void PreprocessForFPConvert(); |
| |
| /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for |
| /// inline asm expressions. |
| virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op, |
| char ConstraintCode, |
| std::vector<SDValue> &OutOps); |
| |
| void EmitSpecialCodeForMain(MachineBasicBlock *BB, MachineFrameInfo *MFI); |
| |
| inline void getAddressOperands(X86ISelAddressMode &AM, SDValue &Base, |
| SDValue &Scale, SDValue &Index, |
| SDValue &Disp) { |
| Base = (AM.BaseType == X86ISelAddressMode::FrameIndexBase) ? |
| CurDAG->getTargetFrameIndex(AM.Base.FrameIndex, TLI.getPointerTy()) : |
| AM.Base.Reg; |
| Scale = getI8Imm(AM.Scale); |
| Index = AM.IndexReg; |
| // These are 32-bit even in 64-bit mode since RIP relative offset |
| // is 32-bit. |
| if (AM.GV) |
| Disp = CurDAG->getTargetGlobalAddress(AM.GV, MVT::i32, AM.Disp); |
| else if (AM.CP) |
| Disp = CurDAG->getTargetConstantPool(AM.CP, MVT::i32, |
| AM.Align, AM.Disp); |
| else if (AM.ES) |
| Disp = CurDAG->getTargetExternalSymbol(AM.ES, MVT::i32); |
| else if (AM.JT != -1) |
| Disp = CurDAG->getTargetJumpTable(AM.JT, MVT::i32); |
| else |
| Disp = getI32Imm(AM.Disp); |
| } |
| |
| /// getI8Imm - Return a target constant with the specified value, of type |
| /// i8. |
| inline SDValue getI8Imm(unsigned Imm) { |
| return CurDAG->getTargetConstant(Imm, MVT::i8); |
| } |
| |
| /// getI16Imm - Return a target constant with the specified value, of type |
| /// i16. |
| inline SDValue getI16Imm(unsigned Imm) { |
| return CurDAG->getTargetConstant(Imm, MVT::i16); |
| } |
| |
| /// getI32Imm - Return a target constant with the specified value, of type |
| /// i32. |
| inline SDValue getI32Imm(unsigned Imm) { |
| return CurDAG->getTargetConstant(Imm, MVT::i32); |
| } |
| |
| /// getGlobalBaseReg - Return an SDNode that returns the value of |
| /// the global base register. Output instructions required to |
| /// initialize the global base register, if necessary. |
| /// |
| SDNode *getGlobalBaseReg(); |
| |
| /// getTruncateTo8Bit - return an SDNode that implements a subreg based |
| /// truncate of the specified operand to i8. This can be done with tablegen, |
| /// except that this code uses MVT::Flag in a tricky way that happens to |
| /// improve scheduling in some cases. |
| SDNode *getTruncateTo8Bit(SDValue N0); |
| |
| #ifndef NDEBUG |
| unsigned Indent; |
| #endif |
| }; |
| } |
| |
| /// findFlagUse - Return use of MVT::Flag value produced by the specified |
| /// SDNode. |
| /// |
| static SDNode *findFlagUse(SDNode *N) { |
| unsigned FlagResNo = N->getNumValues()-1; |
| for (SDNode::use_iterator I = N->use_begin(), E = N->use_end(); I != E; ++I) { |
| SDNode *User = *I; |
| for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) { |
| SDValue Op = User->getOperand(i); |
| if (Op.getNode() == N && Op.getResNo() == FlagResNo) |
| return User; |
| } |
| } |
| return NULL; |
| } |
| |
| /// findNonImmUse - Return true by reference in "found" if "Use" is an |
| /// non-immediate use of "Def". This function recursively traversing |
| /// up the operand chain ignoring certain nodes. |
| static void findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse, |
| SDNode *Root, bool &found, |
| SmallPtrSet<SDNode*, 16> &Visited) { |
| if (found || |
| Use->getNodeId() < Def->getNodeId() || |
| !Visited.insert(Use)) |
| return; |
| |
| for (unsigned i = 0, e = Use->getNumOperands(); !found && i != e; ++i) { |
| SDNode *N = Use->getOperand(i).getNode(); |
| if (N == Def) { |
| if (Use == ImmedUse || Use == Root) |
| continue; // We are not looking for immediate use. |
| assert(N != Root); |
| found = true; |
| break; |
| } |
| |
| // Traverse up the operand chain. |
| findNonImmUse(N, Def, ImmedUse, Root, found, Visited); |
| } |
| } |
| |
| /// isNonImmUse - Start searching from Root up the DAG to check is Def can |
| /// be reached. Return true if that's the case. However, ignore direct uses |
| /// by ImmedUse (which would be U in the example illustrated in |
| /// CanBeFoldedBy) and by Root (which can happen in the store case). |
| /// FIXME: to be really generic, we should allow direct use by any node |
| /// that is being folded. But realisticly since we only fold loads which |
| /// have one non-chain use, we only need to watch out for load/op/store |
| /// and load/op/cmp case where the root (store / cmp) may reach the load via |
| /// its chain operand. |
| static inline bool isNonImmUse(SDNode *Root, SDNode *Def, SDNode *ImmedUse) { |
| SmallPtrSet<SDNode*, 16> Visited; |
| bool found = false; |
| findNonImmUse(Root, Def, ImmedUse, Root, found, Visited); |
| return found; |
| } |
| |
| |
| bool X86DAGToDAGISel::CanBeFoldedBy(SDNode *N, SDNode *U, SDNode *Root) const { |
| if (Fast) return false; |
| |
| // If Root use can somehow reach N through a path that that doesn't contain |
| // U then folding N would create a cycle. e.g. In the following |
| // diagram, Root can reach N through X. If N is folded into into Root, then |
| // X is both a predecessor and a successor of U. |
| // |
| // [N*] // |
| // ^ ^ // |
| // / \ // |
| // [U*] [X]? // |
| // ^ ^ // |
| // \ / // |
| // \ / // |
| // [Root*] // |
| // |
| // * indicates nodes to be folded together. |
| // |
| // If Root produces a flag, then it gets (even more) interesting. Since it |
| // will be "glued" together with its flag use in the scheduler, we need to |
| // check if it might reach N. |
| // |
| // [N*] // |
| // ^ ^ // |
| // / \ // |
| // [U*] [X]? // |
| // ^ ^ // |
| // \ \ // |
| // \ | // |
| // [Root*] | // |
| // ^ | // |
| // f | // |
| // | / // |
| // [Y] / // |
| // ^ / // |
| // f / // |
| // | / // |
| // [FU] // |
| // |
| // If FU (flag use) indirectly reaches N (the load), and Root folds N |
| // (call it Fold), then X is a predecessor of FU and a successor of |
| // Fold. But since Fold and FU are flagged together, this will create |
| // a cycle in the scheduling graph. |
| |
| MVT VT = Root->getValueType(Root->getNumValues()-1); |
| while (VT == MVT::Flag) { |
| SDNode *FU = findFlagUse(Root); |
| if (FU == NULL) |
| break; |
| Root = FU; |
| VT = Root->getValueType(Root->getNumValues()-1); |
| } |
| |
| return !isNonImmUse(Root, N, U); |
| } |
| |
| /// MoveBelowTokenFactor - Replace TokenFactor operand with load's chain operand |
| /// and move load below the TokenFactor. Replace store's chain operand with |
| /// load's chain result. |
| static void MoveBelowTokenFactor(SelectionDAG *CurDAG, SDValue Load, |
| SDValue Store, SDValue TF) { |
| SmallVector<SDValue, 4> Ops; |
| for (unsigned i = 0, e = TF.getNode()->getNumOperands(); i != e; ++i) |
| if (Load.getNode() == TF.getOperand(i).getNode()) |
| Ops.push_back(Load.getOperand(0)); |
| else |
| Ops.push_back(TF.getOperand(i)); |
| CurDAG->UpdateNodeOperands(TF, &Ops[0], Ops.size()); |
| CurDAG->UpdateNodeOperands(Load, TF, Load.getOperand(1), Load.getOperand(2)); |
| CurDAG->UpdateNodeOperands(Store, Load.getValue(1), Store.getOperand(1), |
| Store.getOperand(2), Store.getOperand(3)); |
| } |
| |
| /// isRMWLoad - Return true if N is a load that's part of RMW sub-DAG. |
| /// |
| static bool isRMWLoad(SDValue N, SDValue Chain, SDValue Address, |
| SDValue &Load) { |
| if (N.getOpcode() == ISD::BIT_CONVERT) |
| N = N.getOperand(0); |
| |
| LoadSDNode *LD = dyn_cast<LoadSDNode>(N); |
| if (!LD || LD->isVolatile()) |
| return false; |
| if (LD->getAddressingMode() != ISD::UNINDEXED) |
| return false; |
| |
| ISD::LoadExtType ExtType = LD->getExtensionType(); |
| if (ExtType != ISD::NON_EXTLOAD && ExtType != ISD::EXTLOAD) |
| return false; |
| |
| if (N.hasOneUse() && |
| N.getOperand(1) == Address && |
| N.getNode()->isOperandOf(Chain.getNode())) { |
| Load = N; |
| return true; |
| } |
| return false; |
| } |
| |
| /// MoveBelowCallSeqStart - Replace CALLSEQ_START operand with load's chain |
| /// operand and move load below the call's chain operand. |
| static void MoveBelowCallSeqStart(SelectionDAG *CurDAG, SDValue Load, |
| SDValue Call, SDValue Chain) { |
| SmallVector<SDValue, 8> Ops; |
| for (unsigned i = 0, e = Chain.getNode()->getNumOperands(); i != e; ++i) |
| if (Load.getNode() == Chain.getOperand(i).getNode()) |
| Ops.push_back(Load.getOperand(0)); |
| else |
| Ops.push_back(Chain.getOperand(i)); |
| CurDAG->UpdateNodeOperands(Chain, &Ops[0], Ops.size()); |
| CurDAG->UpdateNodeOperands(Load, Call.getOperand(0), |
| Load.getOperand(1), Load.getOperand(2)); |
| Ops.clear(); |
| Ops.push_back(SDValue(Load.getNode(), 1)); |
| for (unsigned i = 1, e = Call.getNode()->getNumOperands(); i != e; ++i) |
| Ops.push_back(Call.getOperand(i)); |
| CurDAG->UpdateNodeOperands(Call, &Ops[0], Ops.size()); |
| } |
| |
| /// isCalleeLoad - Return true if call address is a load and it can be |
| /// moved below CALLSEQ_START and the chains leading up to the call. |
| /// Return the CALLSEQ_START by reference as a second output. |
| static bool isCalleeLoad(SDValue Callee, SDValue &Chain) { |
| if (Callee.getNode() == Chain.getNode() || !Callee.hasOneUse()) |
| return false; |
| LoadSDNode *LD = dyn_cast<LoadSDNode>(Callee.getNode()); |
| if (!LD || |
| LD->isVolatile() || |
| LD->getAddressingMode() != ISD::UNINDEXED || |
| LD->getExtensionType() != ISD::NON_EXTLOAD) |
| return false; |
| |
| // Now let's find the callseq_start. |
| while (Chain.getOpcode() != ISD::CALLSEQ_START) { |
| if (!Chain.hasOneUse()) |
| return false; |
| Chain = Chain.getOperand(0); |
| } |
| return Chain.getOperand(0).getNode() == Callee.getNode(); |
| } |
| |
| |
| /// PreprocessForRMW - Preprocess the DAG to make instruction selection better. |
| /// This is only run if not in -fast mode (aka -O0). |
| /// This allows the instruction selector to pick more read-modify-write |
| /// instructions. This is a common case: |
| /// |
| /// [Load chain] |
| /// ^ |
| /// | |
| /// [Load] |
| /// ^ ^ |
| /// | | |
| /// / \- |
| /// / | |
| /// [TokenFactor] [Op] |
| /// ^ ^ |
| /// | | |
| /// \ / |
| /// \ / |
| /// [Store] |
| /// |
| /// The fact the store's chain operand != load's chain will prevent the |
| /// (store (op (load))) instruction from being selected. We can transform it to: |
| /// |
| /// [Load chain] |
| /// ^ |
| /// | |
| /// [TokenFactor] |
| /// ^ |
| /// | |
| /// [Load] |
| /// ^ ^ |
| /// | | |
| /// | \- |
| /// | | |
| /// | [Op] |
| /// | ^ |
| /// | | |
| /// \ / |
| /// \ / |
| /// [Store] |
| void X86DAGToDAGISel::PreprocessForRMW() { |
| for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(), |
| E = CurDAG->allnodes_end(); I != E; ++I) { |
| if (I->getOpcode() == X86ISD::CALL) { |
| /// Also try moving call address load from outside callseq_start to just |
| /// before the call to allow it to be folded. |
| /// |
| /// [Load chain] |
| /// ^ |
| /// | |
| /// [Load] |
| /// ^ ^ |
| /// | | |
| /// / \-- |
| /// / | |
| ///[CALLSEQ_START] | |
| /// ^ | |
| /// | | |
| /// [LOAD/C2Reg] | |
| /// | | |
| /// \ / |
| /// \ / |
| /// [CALL] |
| SDValue Chain = I->getOperand(0); |
| SDValue Load = I->getOperand(1); |
| if (!isCalleeLoad(Load, Chain)) |
| continue; |
| MoveBelowCallSeqStart(CurDAG, Load, SDValue(I, 0), Chain); |
| ++NumLoadMoved; |
| continue; |
| } |
| |
| if (!ISD::isNON_TRUNCStore(I)) |
| continue; |
| SDValue Chain = I->getOperand(0); |
| |
| if (Chain.getNode()->getOpcode() != ISD::TokenFactor) |
| continue; |
| |
| SDValue N1 = I->getOperand(1); |
| SDValue N2 = I->getOperand(2); |
| if ((N1.getValueType().isFloatingPoint() && |
| !N1.getValueType().isVector()) || |
| !N1.hasOneUse()) |
| continue; |
| |
| bool RModW = false; |
| SDValue Load; |
| unsigned Opcode = N1.getNode()->getOpcode(); |
| switch (Opcode) { |
| case ISD::ADD: |
| case ISD::MUL: |
| case ISD::AND: |
| case ISD::OR: |
| case ISD::XOR: |
| case ISD::ADDC: |
| case ISD::ADDE: |
| case ISD::VECTOR_SHUFFLE: { |
| SDValue N10 = N1.getOperand(0); |
| SDValue N11 = N1.getOperand(1); |
| RModW = isRMWLoad(N10, Chain, N2, Load); |
| if (!RModW) |
| RModW = isRMWLoad(N11, Chain, N2, Load); |
| break; |
| } |
| case ISD::SUB: |
| case ISD::SHL: |
| case ISD::SRA: |
| case ISD::SRL: |
| case ISD::ROTL: |
| case ISD::ROTR: |
| case ISD::SUBC: |
| case ISD::SUBE: |
| case X86ISD::SHLD: |
| case X86ISD::SHRD: { |
| SDValue N10 = N1.getOperand(0); |
| RModW = isRMWLoad(N10, Chain, N2, Load); |
| break; |
| } |
| } |
| |
| if (RModW) { |
| MoveBelowTokenFactor(CurDAG, Load, SDValue(I, 0), Chain); |
| ++NumLoadMoved; |
| } |
| } |
| } |
| |
| |
| /// PreprocessForFPConvert - Walk over the dag lowering fpround and fpextend |
| /// nodes that target the FP stack to be store and load to the stack. This is a |
| /// gross hack. We would like to simply mark these as being illegal, but when |
| /// we do that, legalize produces these when it expands calls, then expands |
| /// these in the same legalize pass. We would like dag combine to be able to |
| /// hack on these between the call expansion and the node legalization. As such |
| /// this pass basically does "really late" legalization of these inline with the |
| /// X86 isel pass. |
| void X86DAGToDAGISel::PreprocessForFPConvert() { |
| for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(), |
| E = CurDAG->allnodes_end(); I != E; ) { |
| SDNode *N = I++; // Preincrement iterator to avoid invalidation issues. |
| if (N->getOpcode() != ISD::FP_ROUND && N->getOpcode() != ISD::FP_EXTEND) |
| continue; |
| |
| // If the source and destination are SSE registers, then this is a legal |
| // conversion that should not be lowered. |
| MVT SrcVT = N->getOperand(0).getValueType(); |
| MVT DstVT = N->getValueType(0); |
| bool SrcIsSSE = X86Lowering.isScalarFPTypeInSSEReg(SrcVT); |
| bool DstIsSSE = X86Lowering.isScalarFPTypeInSSEReg(DstVT); |
| if (SrcIsSSE && DstIsSSE) |
| continue; |
| |
| if (!SrcIsSSE && !DstIsSSE) { |
| // If this is an FPStack extension, it is a noop. |
| if (N->getOpcode() == ISD::FP_EXTEND) |
| continue; |
| // If this is a value-preserving FPStack truncation, it is a noop. |
| if (N->getConstantOperandVal(1)) |
| continue; |
| } |
| |
| // Here we could have an FP stack truncation or an FPStack <-> SSE convert. |
| // FPStack has extload and truncstore. SSE can fold direct loads into other |
| // operations. Based on this, decide what we want to do. |
| MVT MemVT; |
| if (N->getOpcode() == ISD::FP_ROUND) |
| MemVT = DstVT; // FP_ROUND must use DstVT, we can't do a 'trunc load'. |
| else |
| MemVT = SrcIsSSE ? SrcVT : DstVT; |
| |
| SDValue MemTmp = CurDAG->CreateStackTemporary(MemVT); |
| |
| // FIXME: optimize the case where the src/dest is a load or store? |
| SDValue Store = CurDAG->getTruncStore(CurDAG->getEntryNode(), |
| N->getOperand(0), |
| MemTmp, NULL, 0, MemVT); |
| SDValue Result = CurDAG->getExtLoad(ISD::EXTLOAD, DstVT, Store, MemTmp, |
| NULL, 0, MemVT); |
| |
| // We're about to replace all uses of the FP_ROUND/FP_EXTEND with the |
| // extload we created. This will cause general havok on the dag because |
| // anything below the conversion could be folded into other existing nodes. |
| // To avoid invalidating 'I', back it up to the convert node. |
| --I; |
| CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Result); |
| |
| // Now that we did that, the node is dead. Increment the iterator to the |
| // next node to process, then delete N. |
| ++I; |
| CurDAG->DeleteNode(N); |
| } |
| } |
| |
| /// InstructionSelectBasicBlock - This callback is invoked by SelectionDAGISel |
| /// when it has created a SelectionDAG for us to codegen. |
| void X86DAGToDAGISel::InstructionSelect() { |
| CurBB = BB; // BB can change as result of isel. |
| const Function *F = CurDAG->getMachineFunction().getFunction(); |
| OptForSize = F->hasFnAttr(Attribute::OptimizeForSize); |
| |
| DEBUG(BB->dump()); |
| if (!Fast) |
| PreprocessForRMW(); |
| |
| // FIXME: This should only happen when not -fast. |
| PreprocessForFPConvert(); |
| |
| // Codegen the basic block. |
| #ifndef NDEBUG |
| DOUT << "===== Instruction selection begins:\n"; |
| Indent = 0; |
| #endif |
| SelectRoot(); |
| #ifndef NDEBUG |
| DOUT << "===== Instruction selection ends:\n"; |
| #endif |
| |
| CurDAG->RemoveDeadNodes(); |
| } |
| |
| void X86DAGToDAGISel::InstructionSelectPostProcessing() { |
| // If we are emitting FP stack code, scan the basic block to determine if this |
| // block defines any FP values. If so, put an FP_REG_KILL instruction before |
| // the terminator of the block. |
| |
| // Note that FP stack instructions are used in all modes for long double, |
| // so we always need to do this check. |
| // Also note that it's possible for an FP stack register to be live across |
| // an instruction that produces multiple basic blocks (SSE CMOV) so we |
| // must check all the generated basic blocks. |
| |
| // Scan all of the machine instructions in these MBBs, checking for FP |
| // stores. (RFP32 and RFP64 will not exist in SSE mode, but RFP80 might.) |
| MachineFunction::iterator MBBI = CurBB; |
| MachineFunction::iterator EndMBB = BB; ++EndMBB; |
| for (; MBBI != EndMBB; ++MBBI) { |
| MachineBasicBlock *MBB = MBBI; |
| |
| // If this block returns, ignore it. We don't want to insert an FP_REG_KILL |
| // before the return. |
| if (!MBB->empty()) { |
| MachineBasicBlock::iterator EndI = MBB->end(); |
| --EndI; |
| if (EndI->getDesc().isReturn()) |
| continue; |
| } |
| |
| bool ContainsFPCode = false; |
| for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end(); |
| !ContainsFPCode && I != E; ++I) { |
| if (I->getNumOperands() != 0 && I->getOperand(0).isReg()) { |
| const TargetRegisterClass *clas; |
| for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) { |
| if (I->getOperand(op).isReg() && I->getOperand(op).isDef() && |
| TargetRegisterInfo::isVirtualRegister(I->getOperand(op).getReg()) && |
| ((clas = RegInfo->getRegClass(I->getOperand(0).getReg())) == |
| X86::RFP32RegisterClass || |
| clas == X86::RFP64RegisterClass || |
| clas == X86::RFP80RegisterClass)) { |
| ContainsFPCode = true; |
| break; |
| } |
| } |
| } |
| } |
| // Check PHI nodes in successor blocks. These PHI's will be lowered to have |
| // a copy of the input value in this block. In SSE mode, we only care about |
| // 80-bit values. |
| if (!ContainsFPCode) { |
| // Final check, check LLVM BB's that are successors to the LLVM BB |
| // corresponding to BB for FP PHI nodes. |
| const BasicBlock *LLVMBB = BB->getBasicBlock(); |
| const PHINode *PN; |
| for (succ_const_iterator SI = succ_begin(LLVMBB), E = succ_end(LLVMBB); |
| !ContainsFPCode && SI != E; ++SI) { |
| for (BasicBlock::const_iterator II = SI->begin(); |
| (PN = dyn_cast<PHINode>(II)); ++II) { |
| if (PN->getType()==Type::X86_FP80Ty || |
| (!Subtarget->hasSSE1() && PN->getType()->isFloatingPoint()) || |
| (!Subtarget->hasSSE2() && PN->getType()==Type::DoubleTy)) { |
| ContainsFPCode = true; |
| break; |
| } |
| } |
| } |
| } |
| // Finally, if we found any FP code, emit the FP_REG_KILL instruction. |
| if (ContainsFPCode) { |
| BuildMI(*MBB, MBBI->getFirstTerminator(), |
| TM.getInstrInfo()->get(X86::FP_REG_KILL)); |
| ++NumFPKill; |
| } |
| } |
| } |
| |
| /// EmitSpecialCodeForMain - Emit any code that needs to be executed only in |
| /// the main function. |
| void X86DAGToDAGISel::EmitSpecialCodeForMain(MachineBasicBlock *BB, |
| MachineFrameInfo *MFI) { |
| const TargetInstrInfo *TII = TM.getInstrInfo(); |
| if (Subtarget->isTargetCygMing()) |
| BuildMI(BB, TII->get(X86::CALLpcrel32)).addExternalSymbol("__main"); |
| } |
| |
| void X86DAGToDAGISel::EmitFunctionEntryCode(Function &Fn, MachineFunction &MF) { |
| // If this is main, emit special code for main. |
| MachineBasicBlock *BB = MF.begin(); |
| if (Fn.hasExternalLinkage() && Fn.getName() == "main") |
| EmitSpecialCodeForMain(BB, MF.getFrameInfo()); |
| } |
| |
| /// MatchAddress - Add the specified node to the specified addressing mode, |
| /// returning true if it cannot be done. This just pattern matches for the |
| /// addressing mode. |
| bool X86DAGToDAGISel::MatchAddress(SDValue N, X86ISelAddressMode &AM, |
| bool isRoot, unsigned Depth) { |
| DOUT << "MatchAddress: "; DEBUG(AM.dump()); |
| // Limit recursion. |
| if (Depth > 5) |
| return MatchAddressBase(N, AM, isRoot, Depth); |
| |
| // RIP relative addressing: %rip + 32-bit displacement! |
| if (AM.isRIPRel) { |
| if (!AM.ES && AM.JT != -1 && N.getOpcode() == ISD::Constant) { |
| int64_t Val = cast<ConstantSDNode>(N)->getSExtValue(); |
| if (isInt32(AM.Disp + Val)) { |
| AM.Disp += Val; |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| int id = N.getNode()->getNodeId(); |
| bool AlreadySelected = isSelected(id); // Already selected, not yet replaced. |
| |
| switch (N.getOpcode()) { |
| default: break; |
| case ISD::Constant: { |
| int64_t Val = cast<ConstantSDNode>(N)->getSExtValue(); |
| if (isInt32(AM.Disp + Val)) { |
| AM.Disp += Val; |
| return false; |
| } |
| break; |
| } |
| |
| case X86ISD::Wrapper: { |
| DOUT << "Wrapper: 64bit " << Subtarget->is64Bit(); |
| DOUT << " AM "; DEBUG(AM.dump()); DOUT << "\n"; |
| DOUT << "AlreadySelected " << AlreadySelected << "\n"; |
| bool is64Bit = Subtarget->is64Bit(); |
| // Under X86-64 non-small code model, GV (and friends) are 64-bits. |
| // Also, base and index reg must be 0 in order to use rip as base. |
| if (is64Bit && (TM.getCodeModel() != CodeModel::Small || |
| AM.Base.Reg.getNode() || AM.IndexReg.getNode())) |
| break; |
| if (AM.GV != 0 || AM.CP != 0 || AM.ES != 0 || AM.JT != -1) |
| break; |
| // If value is available in a register both base and index components have |
| // been picked, we can't fit the result available in the register in the |
| // addressing mode. Duplicate GlobalAddress or ConstantPool as displacement. |
| if (!AlreadySelected || (AM.Base.Reg.getNode() && AM.IndexReg.getNode())) { |
| SDValue N0 = N.getOperand(0); |
| if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(N0)) { |
| GlobalValue *GV = G->getGlobal(); |
| AM.GV = GV; |
| AM.Disp += G->getOffset(); |
| AM.isRIPRel = TM.symbolicAddressesAreRIPRel(); |
| return false; |
| } else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(N0)) { |
| AM.CP = CP->getConstVal(); |
| AM.Align = CP->getAlignment(); |
| AM.Disp += CP->getOffset(); |
| AM.isRIPRel = TM.symbolicAddressesAreRIPRel(); |
| return false; |
| } else if (ExternalSymbolSDNode *S =dyn_cast<ExternalSymbolSDNode>(N0)) { |
| AM.ES = S->getSymbol(); |
| AM.isRIPRel = TM.symbolicAddressesAreRIPRel(); |
| return false; |
| } else if (JumpTableSDNode *J = dyn_cast<JumpTableSDNode>(N0)) { |
| AM.JT = J->getIndex(); |
| AM.isRIPRel = TM.symbolicAddressesAreRIPRel(); |
| return false; |
| } |
| } |
| break; |
| } |
| |
| case ISD::FrameIndex: |
| if (AM.BaseType == X86ISelAddressMode::RegBase |
| && AM.Base.Reg.getNode() == 0) { |
| AM.BaseType = X86ISelAddressMode::FrameIndexBase; |
| AM.Base.FrameIndex = cast<FrameIndexSDNode>(N)->getIndex(); |
| return false; |
| } |
| break; |
| |
| case ISD::SHL: |
| if (AlreadySelected || AM.IndexReg.getNode() != 0 |
| || AM.Scale != 1 || AM.isRIPRel) |
| break; |
| |
| if (ConstantSDNode |
| *CN = dyn_cast<ConstantSDNode>(N.getNode()->getOperand(1))) { |
| unsigned Val = CN->getZExtValue(); |
| if (Val == 1 || Val == 2 || Val == 3) { |
| AM.Scale = 1 << Val; |
| SDValue ShVal = N.getNode()->getOperand(0); |
| |
| // Okay, we know that we have a scale by now. However, if the scaled |
| // value is an add of something and a constant, we can fold the |
| // constant into the disp field here. |
| if (ShVal.getNode()->getOpcode() == ISD::ADD && ShVal.hasOneUse() && |
| isa<ConstantSDNode>(ShVal.getNode()->getOperand(1))) { |
| AM.IndexReg = ShVal.getNode()->getOperand(0); |
| ConstantSDNode *AddVal = |
| cast<ConstantSDNode>(ShVal.getNode()->getOperand(1)); |
| uint64_t Disp = AM.Disp + (AddVal->getZExtValue() << Val); |
| if (isInt32(Disp)) |
| AM.Disp = Disp; |
| else |
| AM.IndexReg = ShVal; |
| } else { |
| AM.IndexReg = ShVal; |
| } |
| return false; |
| } |
| break; |
| } |
| |
| case ISD::SMUL_LOHI: |
| case ISD::UMUL_LOHI: |
| // A mul_lohi where we need the low part can be folded as a plain multiply. |
| if (N.getResNo() != 0) break; |
| // FALL THROUGH |
| case ISD::MUL: |
| // X*[3,5,9] -> X+X*[2,4,8] |
| if (!AlreadySelected && |
| AM.BaseType == X86ISelAddressMode::RegBase && |
| AM.Base.Reg.getNode() == 0 && |
| AM.IndexReg.getNode() == 0 && |
| !AM.isRIPRel) { |
| if (ConstantSDNode |
| *CN = dyn_cast<ConstantSDNode>(N.getNode()->getOperand(1))) |
| if (CN->getZExtValue() == 3 || CN->getZExtValue() == 5 || |
| CN->getZExtValue() == 9) { |
| AM.Scale = unsigned(CN->getZExtValue())-1; |
| |
| SDValue MulVal = N.getNode()->getOperand(0); |
| SDValue Reg; |
| |
| // Okay, we know that we have a scale by now. However, if the scaled |
| // value is an add of something and a constant, we can fold the |
| // constant into the disp field here. |
| if (MulVal.getNode()->getOpcode() == ISD::ADD && MulVal.hasOneUse() && |
| isa<ConstantSDNode>(MulVal.getNode()->getOperand(1))) { |
| Reg = MulVal.getNode()->getOperand(0); |
| ConstantSDNode *AddVal = |
| cast<ConstantSDNode>(MulVal.getNode()->getOperand(1)); |
| uint64_t Disp = AM.Disp + AddVal->getZExtValue() * |
| CN->getZExtValue(); |
| if (isInt32(Disp)) |
| AM.Disp = Disp; |
| else |
| Reg = N.getNode()->getOperand(0); |
| } else { |
| Reg = N.getNode()->getOperand(0); |
| } |
| |
| AM.IndexReg = AM.Base.Reg = Reg; |
| return false; |
| } |
| } |
| break; |
| |
| case ISD::ADD: |
| if (!AlreadySelected) { |
| X86ISelAddressMode Backup = AM; |
| if (!MatchAddress(N.getNode()->getOperand(0), AM, false, Depth+1) && |
| !MatchAddress(N.getNode()->getOperand(1), AM, false, Depth+1)) |
| return false; |
| AM = Backup; |
| if (!MatchAddress(N.getNode()->getOperand(1), AM, false, Depth+1) && |
| !MatchAddress(N.getNode()->getOperand(0), AM, false, Depth+1)) |
| return false; |
| AM = Backup; |
| } |
| break; |
| |
| case ISD::OR: |
| // Handle "X | C" as "X + C" iff X is known to have C bits clear. |
| if (AlreadySelected) break; |
| |
| if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.getOperand(1))) { |
| X86ISelAddressMode Backup = AM; |
| // Start with the LHS as an addr mode. |
| if (!MatchAddress(N.getOperand(0), AM, false) && |
| // Address could not have picked a GV address for the displacement. |
| AM.GV == NULL && |
| // On x86-64, the resultant disp must fit in 32-bits. |
| isInt32(AM.Disp + CN->getSExtValue()) && |
| // Check to see if the LHS & C is zero. |
| CurDAG->MaskedValueIsZero(N.getOperand(0), CN->getAPIntValue())) { |
| AM.Disp += CN->getZExtValue(); |
| return false; |
| } |
| AM = Backup; |
| } |
| break; |
| |
| case ISD::AND: { |
| // Handle "(x << C1) & C2" as "(X & (C2>>C1)) << C1" if safe and if this |
| // allows us to fold the shift into this addressing mode. |
| if (AlreadySelected) break; |
| SDValue Shift = N.getOperand(0); |
| if (Shift.getOpcode() != ISD::SHL) break; |
| |
| // Scale must not be used already. |
| if (AM.IndexReg.getNode() != 0 || AM.Scale != 1) break; |
| |
| // Not when RIP is used as the base. |
| if (AM.isRIPRel) break; |
| |
| ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N.getOperand(1)); |
| ConstantSDNode *C1 = dyn_cast<ConstantSDNode>(Shift.getOperand(1)); |
| if (!C1 || !C2) break; |
| |
| // Not likely to be profitable if either the AND or SHIFT node has more |
| // than one use (unless all uses are for address computation). Besides, |
| // isel mechanism requires their node ids to be reused. |
| if (!N.hasOneUse() || !Shift.hasOneUse()) |
| break; |
| |
| // Verify that the shift amount is something we can fold. |
| unsigned ShiftCst = C1->getZExtValue(); |
| if (ShiftCst != 1 && ShiftCst != 2 && ShiftCst != 3) |
| break; |
| |
| // Get the new AND mask, this folds to a constant. |
| SDValue NewANDMask = CurDAG->getNode(ISD::SRL, N.getValueType(), |
| SDValue(C2, 0), SDValue(C1, 0)); |
| SDValue NewAND = CurDAG->getNode(ISD::AND, N.getValueType(), |
| Shift.getOperand(0), NewANDMask); |
| SDValue NewSHIFT = CurDAG->getNode(ISD::SHL, N.getValueType(), |
| NewAND, SDValue(C1, 0)); |
| NewANDMask.getNode()->setNodeId(Shift.getNode()->getNodeId()); |
| NewAND.getNode()->setNodeId(N.getNode()->getNodeId()); |
| CurDAG->ReplaceAllUsesWith(N, NewSHIFT); |
| |
| AM.Scale = 1 << ShiftCst; |
| AM.IndexReg = NewAND; |
| return false; |
| } |
| } |
| |
| return MatchAddressBase(N, AM, isRoot, Depth); |
| } |
| |
| /// MatchAddressBase - Helper for MatchAddress. Add the specified node to the |
| /// specified addressing mode without any further recursion. |
| bool X86DAGToDAGISel::MatchAddressBase(SDValue N, X86ISelAddressMode &AM, |
| bool isRoot, unsigned Depth) { |
| // Is the base register already occupied? |
| if (AM.BaseType != X86ISelAddressMode::RegBase || AM.Base.Reg.getNode()) { |
| // If so, check to see if the scale index register is set. |
| if (AM.IndexReg.getNode() == 0 && !AM.isRIPRel) { |
| AM.IndexReg = N; |
| AM.Scale = 1; |
| return false; |
| } |
| |
| // Otherwise, we cannot select it. |
| return true; |
| } |
| |
| // Default, generate it as a register. |
| AM.BaseType = X86ISelAddressMode::RegBase; |
| AM.Base.Reg = N; |
| return false; |
| } |
| |
| /// SelectAddr - returns true if it is able pattern match an addressing mode. |
| /// It returns the operands which make up the maximal addressing mode it can |
| /// match by reference. |
| bool X86DAGToDAGISel::SelectAddr(SDValue Op, SDValue N, SDValue &Base, |
| SDValue &Scale, SDValue &Index, |
| SDValue &Disp) { |
| X86ISelAddressMode AM; |
| if (MatchAddress(N, AM)) |
| return false; |
| |
| MVT VT = N.getValueType(); |
| if (AM.BaseType == X86ISelAddressMode::RegBase) { |
| if (!AM.Base.Reg.getNode()) |
| AM.Base.Reg = CurDAG->getRegister(0, VT); |
| } |
| |
| if (!AM.IndexReg.getNode()) |
| AM.IndexReg = CurDAG->getRegister(0, VT); |
| |
| getAddressOperands(AM, Base, Scale, Index, Disp); |
| return true; |
| } |
| |
| /// SelectScalarSSELoad - Match a scalar SSE load. In particular, we want to |
| /// match a load whose top elements are either undef or zeros. The load flavor |
| /// is derived from the type of N, which is either v4f32 or v2f64. |
| bool X86DAGToDAGISel::SelectScalarSSELoad(SDValue Op, SDValue Pred, |
| SDValue N, SDValue &Base, |
| SDValue &Scale, SDValue &Index, |
| SDValue &Disp, SDValue &InChain, |
| SDValue &OutChain) { |
| if (N.getOpcode() == ISD::SCALAR_TO_VECTOR) { |
| InChain = N.getOperand(0).getValue(1); |
| if (ISD::isNON_EXTLoad(InChain.getNode()) && |
| InChain.getValue(0).hasOneUse() && |
| N.hasOneUse() && |
| CanBeFoldedBy(N.getNode(), Pred.getNode(), Op.getNode())) { |
| LoadSDNode *LD = cast<LoadSDNode>(InChain); |
| if (!SelectAddr(Op, LD->getBasePtr(), Base, Scale, Index, Disp)) |
| return false; |
| OutChain = LD->getChain(); |
| return true; |
| } |
| } |
| |
| // Also handle the case where we explicitly require zeros in the top |
| // elements. This is a vector shuffle from the zero vector. |
| if (N.getOpcode() == X86ISD::VZEXT_MOVL && N.getNode()->hasOneUse() && |
| // Check to see if the top elements are all zeros (or bitcast of zeros). |
| N.getOperand(0).getOpcode() == ISD::SCALAR_TO_VECTOR && |
| N.getOperand(0).getNode()->hasOneUse() && |
| ISD::isNON_EXTLoad(N.getOperand(0).getOperand(0).getNode()) && |
| N.getOperand(0).getOperand(0).hasOneUse()) { |
| // Okay, this is a zero extending load. Fold it. |
| LoadSDNode *LD = cast<LoadSDNode>(N.getOperand(0).getOperand(0)); |
| if (!SelectAddr(Op, LD->getBasePtr(), Base, Scale, Index, Disp)) |
| return false; |
| OutChain = LD->getChain(); |
| InChain = SDValue(LD, 1); |
| return true; |
| } |
| return false; |
| } |
| |
| |
| /// SelectLEAAddr - it calls SelectAddr and determines if the maximal addressing |
| /// mode it matches can be cost effectively emitted as an LEA instruction. |
| bool X86DAGToDAGISel::SelectLEAAddr(SDValue Op, SDValue N, |
| SDValue &Base, SDValue &Scale, |
| SDValue &Index, SDValue &Disp) { |
| X86ISelAddressMode AM; |
| if (MatchAddress(N, AM)) |
| return false; |
| |
| MVT VT = N.getValueType(); |
| unsigned Complexity = 0; |
| if (AM.BaseType == X86ISelAddressMode::RegBase) |
| if (AM.Base.Reg.getNode()) |
| Complexity = 1; |
| else |
| AM.Base.Reg = CurDAG->getRegister(0, VT); |
| else if (AM.BaseType == X86ISelAddressMode::FrameIndexBase) |
| Complexity = 4; |
| |
| if (AM.IndexReg.getNode()) |
| Complexity++; |
| else |
| AM.IndexReg = CurDAG->getRegister(0, VT); |
| |
| // Don't match just leal(,%reg,2). It's cheaper to do addl %reg, %reg, or with |
| // a simple shift. |
| if (AM.Scale > 1) |
| Complexity++; |
| |
| // FIXME: We are artificially lowering the criteria to turn ADD %reg, $GA |
| // to a LEA. This is determined with some expermentation but is by no means |
| // optimal (especially for code size consideration). LEA is nice because of |
| // its three-address nature. Tweak the cost function again when we can run |
| // convertToThreeAddress() at register allocation time. |
| if (AM.GV || AM.CP || AM.ES || AM.JT != -1) { |
| // For X86-64, we should always use lea to materialize RIP relative |
| // addresses. |
| if (Subtarget->is64Bit()) |
| Complexity = 4; |
| else |
| Complexity += 2; |
| } |
| |
| if (AM.Disp && (AM.Base.Reg.getNode() || AM.IndexReg.getNode())) |
| Complexity++; |
| |
| if (Complexity > 2) { |
| getAddressOperands(AM, Base, Scale, Index, Disp); |
| return true; |
| } |
| return false; |
| } |
| |
| bool X86DAGToDAGISel::TryFoldLoad(SDValue P, SDValue N, |
| SDValue &Base, SDValue &Scale, |
| SDValue &Index, SDValue &Disp) { |
| if (ISD::isNON_EXTLoad(N.getNode()) && |
| N.hasOneUse() && |
| CanBeFoldedBy(N.getNode(), P.getNode(), P.getNode())) |
| return SelectAddr(P, N.getOperand(1), Base, Scale, Index, Disp); |
| return false; |
| } |
| |
| /// getGlobalBaseReg - Return an SDNode that returns the value of |
| /// the global base register. Output instructions required to |
| /// initialize the global base register, if necessary. |
| /// |
| SDNode *X86DAGToDAGISel::getGlobalBaseReg() { |
| MachineFunction *MF = CurBB->getParent(); |
| unsigned GlobalBaseReg = TM.getInstrInfo()->getGlobalBaseReg(MF); |
| return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).getNode(); |
| } |
| |
| static SDNode *FindCallStartFromCall(SDNode *Node) { |
| if (Node->getOpcode() == ISD::CALLSEQ_START) return Node; |
| assert(Node->getOperand(0).getValueType() == MVT::Other && |
| "Node doesn't have a token chain argument!"); |
| return FindCallStartFromCall(Node->getOperand(0).getNode()); |
| } |
| |
| /// getTruncateTo8Bit - return an SDNode that implements a subreg based |
| /// truncate of the specified operand to i8. This can be done with tablegen, |
| /// except that this code uses MVT::Flag in a tricky way that happens to |
| /// improve scheduling in some cases. |
| SDNode *X86DAGToDAGISel::getTruncateTo8Bit(SDValue N0) { |
| assert(!Subtarget->is64Bit() && |
| "getTruncateTo8Bit is only needed on x86-32!"); |
| SDValue SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1 |
| |
| // Ensure that the source register has an 8-bit subreg on 32-bit targets |
| unsigned Opc; |
| MVT N0VT = N0.getValueType(); |
| switch (N0VT.getSimpleVT()) { |
| default: assert(0 && "Unknown truncate!"); |
| case MVT::i16: |
| Opc = X86::MOV16to16_; |
| break; |
| case MVT::i32: |
| Opc = X86::MOV32to32_; |
| break; |
| } |
| |
| // The use of MVT::Flag here is not strictly accurate, but it helps |
| // scheduling in some cases. |
| N0 = SDValue(CurDAG->getTargetNode(Opc, N0VT, MVT::Flag, N0), 0); |
| return CurDAG->getTargetNode(X86::EXTRACT_SUBREG, |
| MVT::i8, N0, SRIdx, N0.getValue(1)); |
| } |
| |
| SDNode *X86DAGToDAGISel::SelectAtomic64(SDNode *Node, unsigned Opc) { |
| SDValue Chain = Node->getOperand(0); |
| SDValue In1 = Node->getOperand(1); |
| SDValue In2L = Node->getOperand(2); |
| SDValue In2H = Node->getOperand(3); |
| SDValue Tmp0, Tmp1, Tmp2, Tmp3; |
| if (!SelectAddr(In1, In1, Tmp0, Tmp1, Tmp2, Tmp3)) |
| return NULL; |
| SDValue LSI = Node->getOperand(4); // MemOperand |
| AddToISelQueue(Tmp0); |
| AddToISelQueue(Tmp1); |
| AddToISelQueue(Tmp2); |
| AddToISelQueue(Tmp3); |
| AddToISelQueue(In2L); |
| AddToISelQueue(In2H); |
| // For now, don't select the MemOperand object, we don't know how. |
| AddToISelQueue(Chain); |
| const SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, In2L, In2H, LSI, Chain }; |
| return CurDAG->getTargetNode(Opc, MVT::i32, MVT::i32, MVT::Other, Ops, 8); |
| } |
| |
| SDNode *X86DAGToDAGISel::Select(SDValue N) { |
| SDNode *Node = N.getNode(); |
| MVT NVT = Node->getValueType(0); |
| unsigned Opc, MOpc; |
| unsigned Opcode = Node->getOpcode(); |
| |
| #ifndef NDEBUG |
| DOUT << std::string(Indent, ' ') << "Selecting: "; |
| DEBUG(Node->dump(CurDAG)); |
| DOUT << "\n"; |
| Indent += 2; |
| #endif |
| |
| if (Node->isMachineOpcode()) { |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "== "; |
| DEBUG(Node->dump(CurDAG)); |
| DOUT << "\n"; |
| Indent -= 2; |
| #endif |
| return NULL; // Already selected. |
| } |
| |
| switch (Opcode) { |
| default: break; |
| case X86ISD::GlobalBaseReg: |
| return getGlobalBaseReg(); |
| |
| case ISD::ADD: { |
| // Turn ADD X, c to MOV32ri X+c. This cannot be done with tblgen'd |
| // code and is matched first so to prevent it from being turned into |
| // LEA32r X+c. |
| // In 64-bit small code size mode, use LEA to take advantage of |
| // RIP-relative addressing. |
| if (TM.getCodeModel() != CodeModel::Small) |
| break; |
| MVT PtrVT = TLI.getPointerTy(); |
| SDValue N0 = N.getOperand(0); |
| SDValue N1 = N.getOperand(1); |
| if (N.getNode()->getValueType(0) == PtrVT && |
| N0.getOpcode() == X86ISD::Wrapper && |
| N1.getOpcode() == ISD::Constant) { |
| unsigned Offset = (unsigned)cast<ConstantSDNode>(N1)->getZExtValue(); |
| SDValue C(0, 0); |
| // TODO: handle ExternalSymbolSDNode. |
| if (GlobalAddressSDNode *G = |
| dyn_cast<GlobalAddressSDNode>(N0.getOperand(0))) { |
| C = CurDAG->getTargetGlobalAddress(G->getGlobal(), PtrVT, |
| G->getOffset() + Offset); |
| } else if (ConstantPoolSDNode *CP = |
| dyn_cast<ConstantPoolSDNode>(N0.getOperand(0))) { |
| C = CurDAG->getTargetConstantPool(CP->getConstVal(), PtrVT, |
| CP->getAlignment(), |
| CP->getOffset()+Offset); |
| } |
| |
| if (C.getNode()) { |
| if (Subtarget->is64Bit()) { |
| SDValue Ops[] = { CurDAG->getRegister(0, PtrVT), getI8Imm(1), |
| CurDAG->getRegister(0, PtrVT), C }; |
| return CurDAG->SelectNodeTo(N.getNode(), X86::LEA64r, |
| MVT::i64, Ops, 4); |
| } else |
| return CurDAG->SelectNodeTo(N.getNode(), X86::MOV32ri, PtrVT, C); |
| } |
| } |
| |
| // Other cases are handled by auto-generated code. |
| break; |
| } |
| |
| case X86ISD::ATOMOR64_DAG: |
| return SelectAtomic64(Node, X86::ATOMOR6432); |
| case X86ISD::ATOMXOR64_DAG: |
| return SelectAtomic64(Node, X86::ATOMXOR6432); |
| case X86ISD::ATOMADD64_DAG: |
| return SelectAtomic64(Node, X86::ATOMADD6432); |
| case X86ISD::ATOMSUB64_DAG: |
| return SelectAtomic64(Node, X86::ATOMSUB6432); |
| case X86ISD::ATOMNAND64_DAG: |
| return SelectAtomic64(Node, X86::ATOMNAND6432); |
| case X86ISD::ATOMAND64_DAG: |
| return SelectAtomic64(Node, X86::ATOMAND6432); |
| case X86ISD::ATOMSWAP64_DAG: |
| return SelectAtomic64(Node, X86::ATOMSWAP6432); |
| |
| case ISD::SMUL_LOHI: |
| case ISD::UMUL_LOHI: { |
| SDValue N0 = Node->getOperand(0); |
| SDValue N1 = Node->getOperand(1); |
| |
| bool isSigned = Opcode == ISD::SMUL_LOHI; |
| if (!isSigned) |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: Opc = X86::MUL8r; MOpc = X86::MUL8m; break; |
| case MVT::i16: Opc = X86::MUL16r; MOpc = X86::MUL16m; break; |
| case MVT::i32: Opc = X86::MUL32r; MOpc = X86::MUL32m; break; |
| case MVT::i64: Opc = X86::MUL64r; MOpc = X86::MUL64m; break; |
| } |
| else |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: Opc = X86::IMUL8r; MOpc = X86::IMUL8m; break; |
| case MVT::i16: Opc = X86::IMUL16r; MOpc = X86::IMUL16m; break; |
| case MVT::i32: Opc = X86::IMUL32r; MOpc = X86::IMUL32m; break; |
| case MVT::i64: Opc = X86::IMUL64r; MOpc = X86::IMUL64m; break; |
| } |
| |
| unsigned LoReg, HiReg; |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: LoReg = X86::AL; HiReg = X86::AH; break; |
| case MVT::i16: LoReg = X86::AX; HiReg = X86::DX; break; |
| case MVT::i32: LoReg = X86::EAX; HiReg = X86::EDX; break; |
| case MVT::i64: LoReg = X86::RAX; HiReg = X86::RDX; break; |
| } |
| |
| SDValue Tmp0, Tmp1, Tmp2, Tmp3; |
| bool foldedLoad = TryFoldLoad(N, N1, Tmp0, Tmp1, Tmp2, Tmp3); |
| // multiplty is commmutative |
| if (!foldedLoad) { |
| foldedLoad = TryFoldLoad(N, N0, Tmp0, Tmp1, Tmp2, Tmp3); |
| if (foldedLoad) |
| std::swap(N0, N1); |
| } |
| |
| AddToISelQueue(N0); |
| SDValue InFlag = CurDAG->getCopyToReg(CurDAG->getEntryNode(), LoReg, |
| N0, SDValue()).getValue(1); |
| |
| if (foldedLoad) { |
| AddToISelQueue(N1.getOperand(0)); |
| AddToISelQueue(Tmp0); |
| AddToISelQueue(Tmp1); |
| AddToISelQueue(Tmp2); |
| AddToISelQueue(Tmp3); |
| SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N1.getOperand(0), InFlag }; |
| SDNode *CNode = |
| CurDAG->getTargetNode(MOpc, MVT::Other, MVT::Flag, Ops, 6); |
| InFlag = SDValue(CNode, 1); |
| // Update the chain. |
| ReplaceUses(N1.getValue(1), SDValue(CNode, 0)); |
| } else { |
| AddToISelQueue(N1); |
| InFlag = |
| SDValue(CurDAG->getTargetNode(Opc, MVT::Flag, N1, InFlag), 0); |
| } |
| |
| // Copy the low half of the result, if it is needed. |
| if (!N.getValue(0).use_empty()) { |
| SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| LoReg, NVT, InFlag); |
| InFlag = Result.getValue(2); |
| ReplaceUses(N.getValue(0), Result); |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(Result.getNode()->dump(CurDAG)); |
| DOUT << "\n"; |
| #endif |
| } |
| // Copy the high half of the result, if it is needed. |
| if (!N.getValue(1).use_empty()) { |
| SDValue Result; |
| if (HiReg == X86::AH && Subtarget->is64Bit()) { |
| // Prevent use of AH in a REX instruction by referencing AX instead. |
| // Shift it down 8 bits. |
| Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| X86::AX, MVT::i16, InFlag); |
| InFlag = Result.getValue(2); |
| Result = SDValue(CurDAG->getTargetNode(X86::SHR16ri, MVT::i16, Result, |
| CurDAG->getTargetConstant(8, MVT::i8)), 0); |
| // Then truncate it down to i8. |
| SDValue SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1 |
| Result = SDValue(CurDAG->getTargetNode(X86::EXTRACT_SUBREG, |
| MVT::i8, Result, SRIdx), 0); |
| } else { |
| Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| HiReg, NVT, InFlag); |
| InFlag = Result.getValue(2); |
| } |
| ReplaceUses(N.getValue(1), Result); |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(Result.getNode()->dump(CurDAG)); |
| DOUT << "\n"; |
| #endif |
| } |
| |
| #ifndef NDEBUG |
| Indent -= 2; |
| #endif |
| |
| return NULL; |
| } |
| |
| case ISD::SDIVREM: |
| case ISD::UDIVREM: { |
| SDValue N0 = Node->getOperand(0); |
| SDValue N1 = Node->getOperand(1); |
| |
| bool isSigned = Opcode == ISD::SDIVREM; |
| if (!isSigned) |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: Opc = X86::DIV8r; MOpc = X86::DIV8m; break; |
| case MVT::i16: Opc = X86::DIV16r; MOpc = X86::DIV16m; break; |
| case MVT::i32: Opc = X86::DIV32r; MOpc = X86::DIV32m; break; |
| case MVT::i64: Opc = X86::DIV64r; MOpc = X86::DIV64m; break; |
| } |
| else |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: Opc = X86::IDIV8r; MOpc = X86::IDIV8m; break; |
| case MVT::i16: Opc = X86::IDIV16r; MOpc = X86::IDIV16m; break; |
| case MVT::i32: Opc = X86::IDIV32r; MOpc = X86::IDIV32m; break; |
| case MVT::i64: Opc = X86::IDIV64r; MOpc = X86::IDIV64m; break; |
| } |
| |
| unsigned LoReg, HiReg; |
| unsigned ClrOpcode, SExtOpcode; |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unsupported VT!"); |
| case MVT::i8: |
| LoReg = X86::AL; HiReg = X86::AH; |
| ClrOpcode = 0; |
| SExtOpcode = X86::CBW; |
| break; |
| case MVT::i16: |
| LoReg = X86::AX; HiReg = X86::DX; |
| ClrOpcode = X86::MOV16r0; |
| SExtOpcode = X86::CWD; |
| break; |
| case MVT::i32: |
| LoReg = X86::EAX; HiReg = X86::EDX; |
| ClrOpcode = X86::MOV32r0; |
| SExtOpcode = X86::CDQ; |
| break; |
| case MVT::i64: |
| LoReg = X86::RAX; HiReg = X86::RDX; |
| ClrOpcode = X86::MOV64r0; |
| SExtOpcode = X86::CQO; |
| break; |
| } |
| |
| SDValue Tmp0, Tmp1, Tmp2, Tmp3; |
| bool foldedLoad = TryFoldLoad(N, N1, Tmp0, Tmp1, Tmp2, Tmp3); |
| |
| SDValue InFlag; |
| if (NVT == MVT::i8 && !isSigned) { |
| // Special case for div8, just use a move with zero extension to AX to |
| // clear the upper 8 bits (AH). |
| SDValue Tmp0, Tmp1, Tmp2, Tmp3, Move, Chain; |
| if (TryFoldLoad(N, N0, Tmp0, Tmp1, Tmp2, Tmp3)) { |
| SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N0.getOperand(0) }; |
| AddToISelQueue(N0.getOperand(0)); |
| AddToISelQueue(Tmp0); |
| AddToISelQueue(Tmp1); |
| AddToISelQueue(Tmp2); |
| AddToISelQueue(Tmp3); |
| Move = |
| SDValue(CurDAG->getTargetNode(X86::MOVZX16rm8, MVT::i16, MVT::Other, |
| Ops, 5), 0); |
| Chain = Move.getValue(1); |
| ReplaceUses(N0.getValue(1), Chain); |
| } else { |
| AddToISelQueue(N0); |
| Move = |
| SDValue(CurDAG->getTargetNode(X86::MOVZX16rr8, MVT::i16, N0), 0); |
| Chain = CurDAG->getEntryNode(); |
| } |
| Chain = CurDAG->getCopyToReg(Chain, X86::AX, Move, SDValue()); |
| InFlag = Chain.getValue(1); |
| } else { |
| AddToISelQueue(N0); |
| InFlag = |
| CurDAG->getCopyToReg(CurDAG->getEntryNode(), |
| LoReg, N0, SDValue()).getValue(1); |
| if (isSigned) { |
| // Sign extend the low part into the high part. |
| InFlag = |
| SDValue(CurDAG->getTargetNode(SExtOpcode, MVT::Flag, InFlag), 0); |
| } else { |
| // Zero out the high part, effectively zero extending the input. |
| SDValue ClrNode = SDValue(CurDAG->getTargetNode(ClrOpcode, NVT), 0); |
| InFlag = CurDAG->getCopyToReg(CurDAG->getEntryNode(), HiReg, |
| ClrNode, InFlag).getValue(1); |
| } |
| } |
| |
| if (foldedLoad) { |
| AddToISelQueue(N1.getOperand(0)); |
| AddToISelQueue(Tmp0); |
| AddToISelQueue(Tmp1); |
| AddToISelQueue(Tmp2); |
| AddToISelQueue(Tmp3); |
| SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N1.getOperand(0), InFlag }; |
| SDNode *CNode = |
| CurDAG->getTargetNode(MOpc, MVT::Other, MVT::Flag, Ops, 6); |
| InFlag = SDValue(CNode, 1); |
| // Update the chain. |
| ReplaceUses(N1.getValue(1), SDValue(CNode, 0)); |
| } else { |
| AddToISelQueue(N1); |
| InFlag = |
| SDValue(CurDAG->getTargetNode(Opc, MVT::Flag, N1, InFlag), 0); |
| } |
| |
| // Copy the division (low) result, if it is needed. |
| if (!N.getValue(0).use_empty()) { |
| SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| LoReg, NVT, InFlag); |
| InFlag = Result.getValue(2); |
| ReplaceUses(N.getValue(0), Result); |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(Result.getNode()->dump(CurDAG)); |
| DOUT << "\n"; |
| #endif |
| } |
| // Copy the remainder (high) result, if it is needed. |
| if (!N.getValue(1).use_empty()) { |
| SDValue Result; |
| if (HiReg == X86::AH && Subtarget->is64Bit()) { |
| // Prevent use of AH in a REX instruction by referencing AX instead. |
| // Shift it down 8 bits. |
| Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| X86::AX, MVT::i16, InFlag); |
| InFlag = Result.getValue(2); |
| Result = SDValue(CurDAG->getTargetNode(X86::SHR16ri, MVT::i16, Result, |
| CurDAG->getTargetConstant(8, MVT::i8)), 0); |
| // Then truncate it down to i8. |
| SDValue SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1 |
| Result = SDValue(CurDAG->getTargetNode(X86::EXTRACT_SUBREG, |
| MVT::i8, Result, SRIdx), 0); |
| } else { |
| Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), |
| HiReg, NVT, InFlag); |
| InFlag = Result.getValue(2); |
| } |
| ReplaceUses(N.getValue(1), Result); |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(Result.getNode()->dump(CurDAG)); |
| DOUT << "\n"; |
| #endif |
| } |
| |
| #ifndef NDEBUG |
| Indent -= 2; |
| #endif |
| |
| return NULL; |
| } |
| |
| case ISD::SIGN_EXTEND_INREG: { |
| MVT SVT = cast<VTSDNode>(Node->getOperand(1))->getVT(); |
| if (SVT == MVT::i8 && !Subtarget->is64Bit()) { |
| SDValue N0 = Node->getOperand(0); |
| AddToISelQueue(N0); |
| |
| SDValue TruncOp = SDValue(getTruncateTo8Bit(N0), 0); |
| unsigned Opc = 0; |
| switch (NVT.getSimpleVT()) { |
| default: assert(0 && "Unknown sign_extend_inreg!"); |
| case MVT::i16: |
| Opc = X86::MOVSX16rr8; |
| break; |
| case MVT::i32: |
| Opc = X86::MOVSX32rr8; |
| break; |
| } |
| |
| SDNode *ResNode = CurDAG->getTargetNode(Opc, NVT, TruncOp); |
| |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(TruncOp.getNode()->dump(CurDAG)); |
| DOUT << "\n"; |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(ResNode->dump(CurDAG)); |
| DOUT << "\n"; |
| Indent -= 2; |
| #endif |
| return ResNode; |
| } |
| break; |
| } |
| |
| case ISD::TRUNCATE: { |
| if (NVT == MVT::i8 && !Subtarget->is64Bit()) { |
| SDValue Input = Node->getOperand(0); |
| AddToISelQueue(Node->getOperand(0)); |
| SDNode *ResNode = getTruncateTo8Bit(Input); |
| |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| DEBUG(ResNode->dump(CurDAG)); |
| DOUT << "\n"; |
| Indent -= 2; |
| #endif |
| return ResNode; |
| } |
| break; |
| } |
| |
| case ISD::DECLARE: { |
| // Handle DECLARE nodes here because the second operand may have been |
| // wrapped in X86ISD::Wrapper. |
| SDValue Chain = Node->getOperand(0); |
| SDValue N1 = Node->getOperand(1); |
| SDValue N2 = Node->getOperand(2); |
| if (!isa<FrameIndexSDNode>(N1)) |
| break; |
| int FI = cast<FrameIndexSDNode>(N1)->getIndex(); |
| if (N2.getOpcode() == ISD::ADD && |
| N2.getOperand(0).getOpcode() == X86ISD::GlobalBaseReg) |
| N2 = N2.getOperand(1); |
| if (N2.getOpcode() == X86ISD::Wrapper && |
| isa<GlobalAddressSDNode>(N2.getOperand(0))) { |
| GlobalValue *GV = |
| cast<GlobalAddressSDNode>(N2.getOperand(0))->getGlobal(); |
| SDValue Tmp1 = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); |
| SDValue Tmp2 = CurDAG->getTargetGlobalAddress(GV, TLI.getPointerTy()); |
| AddToISelQueue(Chain); |
| SDValue Ops[] = { Tmp1, Tmp2, Chain }; |
| return CurDAG->getTargetNode(TargetInstrInfo::DECLARE, |
| MVT::Other, Ops, 3); |
| } |
| break; |
| } |
| } |
| |
| SDNode *ResNode = SelectCode(N); |
| |
| #ifndef NDEBUG |
| DOUT << std::string(Indent-2, ' ') << "=> "; |
| if (ResNode == NULL || ResNode == N.getNode()) |
| DEBUG(N.getNode()->dump(CurDAG)); |
| else |
| DEBUG(ResNode->dump(CurDAG)); |
| DOUT << "\n"; |
| Indent -= 2; |
| #endif |
| |
| return ResNode; |
| } |
| |
| bool X86DAGToDAGISel:: |
| SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode, |
| std::vector<SDValue> &OutOps) { |
| SDValue Op0, Op1, Op2, Op3; |
| switch (ConstraintCode) { |
| case 'o': // offsetable ?? |
| case 'v': // not offsetable ?? |
| default: return true; |
| case 'm': // memory |
| if (!SelectAddr(Op, Op, Op0, Op1, Op2, Op3)) |
| return true; |
| break; |
| } |
| |
| OutOps.push_back(Op0); |
| OutOps.push_back(Op1); |
| OutOps.push_back(Op2); |
| OutOps.push_back(Op3); |
| AddToISelQueue(Op0); |
| AddToISelQueue(Op1); |
| AddToISelQueue(Op2); |
| AddToISelQueue(Op3); |
| return false; |
| } |
| |
| /// createX86ISelDag - This pass converts a legalized DAG into a |
| /// X86-specific DAG, ready for instruction scheduling. |
| /// |
| FunctionPass *llvm::createX86ISelDag(X86TargetMachine &TM, bool Fast) { |
| return new X86DAGToDAGISel(TM, Fast); |
| } |