| //===-- MipsMCCodeEmitter.cpp - Convert Mips Code to Machine Code ---------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the MipsMCCodeEmitter class. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| #define DEBUG_TYPE "mccodeemitter" |
| #include "MCTargetDesc/MipsBaseInfo.h" |
| #include "MCTargetDesc/MipsDirectObjLower.h" |
| #include "MCTargetDesc/MipsFixupKinds.h" |
| #include "MCTargetDesc/MipsMCTargetDesc.h" |
| #include "llvm/ADT/APFloat.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/MC/MCCodeEmitter.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCInst.h" |
| #include "llvm/MC/MCInstrInfo.h" |
| #include "llvm/MC/MCRegisterInfo.h" |
| #include "llvm/MC/MCSubtargetInfo.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace llvm; |
| |
| namespace { |
| class MipsMCCodeEmitter : public MCCodeEmitter { |
| MipsMCCodeEmitter(const MipsMCCodeEmitter &) LLVM_DELETED_FUNCTION; |
| void operator=(const MipsMCCodeEmitter &) LLVM_DELETED_FUNCTION; |
| const MCInstrInfo &MCII; |
| MCContext &Ctx; |
| bool IsLittleEndian; |
| |
| public: |
| MipsMCCodeEmitter(const MCInstrInfo &mcii, MCContext &Ctx_, |
| const MCSubtargetInfo &sti, bool IsLittle) : |
| MCII(mcii), Ctx(Ctx_), IsLittleEndian(IsLittle) {} |
| |
| ~MipsMCCodeEmitter() {} |
| |
| void EmitByte(unsigned char C, raw_ostream &OS) const { |
| OS << (char)C; |
| } |
| |
| void EmitInstruction(uint64_t Val, unsigned Size, raw_ostream &OS) const { |
| // Output the instruction encoding in little endian byte order. |
| for (unsigned i = 0; i < Size; ++i) { |
| unsigned Shift = IsLittleEndian ? i * 8 : (Size - 1 - i) * 8; |
| EmitByte((Val >> Shift) & 0xff, OS); |
| } |
| } |
| |
| void EncodeInstruction(const MCInst &MI, raw_ostream &OS, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| // getBinaryCodeForInstr - TableGen'erated function for getting the |
| // binary encoding for an instruction. |
| uint64_t getBinaryCodeForInstr(const MCInst &MI, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| // getBranchJumpOpValue - Return binary encoding of the jump |
| // target operand. If the machine operand requires relocation, |
| // record the relocation and return zero. |
| unsigned getJumpTargetOpValue(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| // getBranchTargetOpValue - Return binary encoding of the branch |
| // target operand. If the machine operand requires relocation, |
| // record the relocation and return zero. |
| unsigned getBranchTargetOpValue(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| // getMachineOpValue - Return binary encoding of operand. If the machin |
| // operand requires relocation, record the relocation and return zero. |
| unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| unsigned getMemEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| unsigned getSizeExtEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| unsigned getSizeInsEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const; |
| |
| }; // class MipsMCCodeEmitter |
| } // namespace |
| |
| MCCodeEmitter *llvm::createMipsMCCodeEmitterEB(const MCInstrInfo &MCII, |
| const MCRegisterInfo &MRI, |
| const MCSubtargetInfo &STI, |
| MCContext &Ctx) |
| { |
| return new MipsMCCodeEmitter(MCII, Ctx, STI, false); |
| } |
| |
| MCCodeEmitter *llvm::createMipsMCCodeEmitterEL(const MCInstrInfo &MCII, |
| const MCRegisterInfo &MRI, |
| const MCSubtargetInfo &STI, |
| MCContext &Ctx) |
| { |
| return new MipsMCCodeEmitter(MCII, Ctx, STI, true); |
| } |
| |
| /// EncodeInstruction - Emit the instruction. |
| /// Size the instruction (currently only 4 bytes |
| void MipsMCCodeEmitter:: |
| EncodeInstruction(const MCInst &MI, raw_ostream &OS, |
| SmallVectorImpl<MCFixup> &Fixups) const |
| { |
| |
| // Non-pseudo instructions that get changed for direct object |
| // only based on operand values. |
| // If this list of instructions get much longer we will move |
| // the check to a function call. Until then, this is more efficient. |
| MCInst TmpInst = MI; |
| switch (MI.getOpcode()) { |
| // If shift amount is >= 32 it the inst needs to be lowered further |
| case Mips::DSLL: |
| case Mips::DSRL: |
| case Mips::DSRA: |
| Mips::LowerLargeShift(TmpInst); |
| break; |
| // Double extract instruction is chosen by pos and size operands |
| case Mips::DEXT: |
| case Mips::DINS: |
| Mips::LowerDextDins(TmpInst); |
| } |
| |
| uint32_t Binary = getBinaryCodeForInstr(TmpInst, Fixups); |
| |
| // Check for unimplemented opcodes. |
| // Unfortunately in MIPS both NOP and SLL will come in with Binary == 0 |
| // so we have to special check for them. |
| unsigned Opcode = TmpInst.getOpcode(); |
| if ((Opcode != Mips::NOP) && (Opcode != Mips::SLL) && !Binary) |
| llvm_unreachable("unimplemented opcode in EncodeInstruction()"); |
| |
| const MCInstrDesc &Desc = MCII.get(TmpInst.getOpcode()); |
| |
| // Get byte count of instruction |
| unsigned Size = Desc.getSize(); |
| if (!Size) |
| llvm_unreachable("Desc.getSize() returns 0"); |
| |
| EmitInstruction(Binary, Size, OS); |
| } |
| |
| /// getBranchTargetOpValue - Return binary encoding of the branch |
| /// target operand. If the machine operand requires relocation, |
| /// record the relocation and return zero. |
| unsigned MipsMCCodeEmitter:: |
| getBranchTargetOpValue(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| |
| const MCOperand &MO = MI.getOperand(OpNo); |
| |
| // If the destination is an immediate, we have nothing to do. |
| if (MO.isImm()) return MO.getImm(); |
| assert(MO.isExpr() && |
| "getBranchTargetOpValue expects only expressions or immediates"); |
| |
| const MCExpr *Expr = MO.getExpr(); |
| Fixups.push_back(MCFixup::Create(0, Expr, |
| MCFixupKind(Mips::fixup_Mips_PC16))); |
| return 0; |
| } |
| |
| /// getJumpTargetOpValue - Return binary encoding of the jump |
| /// target operand. If the machine operand requires relocation, |
| /// record the relocation and return zero. |
| unsigned MipsMCCodeEmitter:: |
| getJumpTargetOpValue(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| |
| const MCOperand &MO = MI.getOperand(OpNo); |
| // If the destination is an immediate, we have nothing to do. |
| if (MO.isImm()) return MO.getImm(); |
| assert(MO.isExpr() && |
| "getJumpTargetOpValue expects only expressions or an immediate"); |
| |
| const MCExpr *Expr = MO.getExpr(); |
| Fixups.push_back(MCFixup::Create(0, Expr, |
| MCFixupKind(Mips::fixup_Mips_26))); |
| return 0; |
| } |
| |
| /// getMachineOpValue - Return binary encoding of operand. If the machine |
| /// operand requires relocation, record the relocation and return zero. |
| unsigned MipsMCCodeEmitter:: |
| getMachineOpValue(const MCInst &MI, const MCOperand &MO, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| if (MO.isReg()) { |
| unsigned Reg = MO.getReg(); |
| unsigned RegNo = Ctx.getRegisterInfo().getEncodingValue(Reg); |
| return RegNo; |
| } else if (MO.isImm()) { |
| return static_cast<unsigned>(MO.getImm()); |
| } else if (MO.isFPImm()) { |
| return static_cast<unsigned>(APFloat(MO.getFPImm()) |
| .bitcastToAPInt().getHiBits(32).getLimitedValue()); |
| } |
| |
| // MO must be an Expr. |
| assert(MO.isExpr()); |
| |
| const MCExpr *Expr = MO.getExpr(); |
| MCExpr::ExprKind Kind = Expr->getKind(); |
| |
| if (Kind == MCExpr::Binary) { |
| Expr = static_cast<const MCBinaryExpr*>(Expr)->getLHS(); |
| Kind = Expr->getKind(); |
| } |
| |
| assert (Kind == MCExpr::SymbolRef); |
| |
| Mips::Fixups FixupKind = Mips::Fixups(0); |
| |
| switch(cast<MCSymbolRefExpr>(Expr)->getKind()) { |
| default: llvm_unreachable("Unknown fixup kind!"); |
| break; |
| case MCSymbolRefExpr::VK_Mips_GPOFF_HI : |
| FixupKind = Mips::fixup_Mips_GPOFF_HI; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GPOFF_LO : |
| FixupKind = Mips::fixup_Mips_GPOFF_LO; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_PAGE : |
| FixupKind = Mips::fixup_Mips_GOT_PAGE; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_OFST : |
| FixupKind = Mips::fixup_Mips_GOT_OFST; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_DISP : |
| FixupKind = Mips::fixup_Mips_GOT_DISP; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GPREL: |
| FixupKind = Mips::fixup_Mips_GPREL16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_CALL: |
| FixupKind = Mips::fixup_Mips_CALL16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT16: |
| FixupKind = Mips::fixup_Mips_GOT_Global; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT: |
| FixupKind = Mips::fixup_Mips_GOT_Local; |
| break; |
| case MCSymbolRefExpr::VK_Mips_ABS_HI: |
| FixupKind = Mips::fixup_Mips_HI16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_ABS_LO: |
| FixupKind = Mips::fixup_Mips_LO16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_TLSGD: |
| FixupKind = Mips::fixup_Mips_TLSGD; |
| break; |
| case MCSymbolRefExpr::VK_Mips_TLSLDM: |
| FixupKind = Mips::fixup_Mips_TLSLDM; |
| break; |
| case MCSymbolRefExpr::VK_Mips_DTPREL_HI: |
| FixupKind = Mips::fixup_Mips_DTPREL_HI; |
| break; |
| case MCSymbolRefExpr::VK_Mips_DTPREL_LO: |
| FixupKind = Mips::fixup_Mips_DTPREL_LO; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOTTPREL: |
| FixupKind = Mips::fixup_Mips_GOTTPREL; |
| break; |
| case MCSymbolRefExpr::VK_Mips_TPREL_HI: |
| FixupKind = Mips::fixup_Mips_TPREL_HI; |
| break; |
| case MCSymbolRefExpr::VK_Mips_TPREL_LO: |
| FixupKind = Mips::fixup_Mips_TPREL_LO; |
| break; |
| case MCSymbolRefExpr::VK_Mips_HIGHER: |
| FixupKind = Mips::fixup_Mips_HIGHER; |
| break; |
| case MCSymbolRefExpr::VK_Mips_HIGHEST: |
| FixupKind = Mips::fixup_Mips_HIGHEST; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_HI16: |
| FixupKind = Mips::fixup_Mips_GOT_HI16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_GOT_LO16: |
| FixupKind = Mips::fixup_Mips_GOT_LO16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_CALL_HI16: |
| FixupKind = Mips::fixup_Mips_CALL_HI16; |
| break; |
| case MCSymbolRefExpr::VK_Mips_CALL_LO16: |
| FixupKind = Mips::fixup_Mips_CALL_LO16; |
| break; |
| } // switch |
| |
| Fixups.push_back(MCFixup::Create(0, MO.getExpr(), MCFixupKind(FixupKind))); |
| |
| // All of the information is in the fixup. |
| return 0; |
| } |
| |
| /// getMemEncoding - Return binary encoding of memory related operand. |
| /// If the offset operand requires relocation, record the relocation. |
| unsigned |
| MipsMCCodeEmitter::getMemEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| // Base register is encoded in bits 20-16, offset is encoded in bits 15-0. |
| assert(MI.getOperand(OpNo).isReg()); |
| unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),Fixups) << 16; |
| unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups); |
| |
| return (OffBits & 0xFFFF) | RegBits; |
| } |
| |
| unsigned |
| MipsMCCodeEmitter::getSizeExtEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| assert(MI.getOperand(OpNo).isImm()); |
| unsigned SizeEncoding = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups); |
| return SizeEncoding - 1; |
| } |
| |
| // FIXME: should be called getMSBEncoding |
| // |
| unsigned |
| MipsMCCodeEmitter::getSizeInsEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups) const { |
| assert(MI.getOperand(OpNo-1).isImm()); |
| assert(MI.getOperand(OpNo).isImm()); |
| unsigned Position = getMachineOpValue(MI, MI.getOperand(OpNo-1), Fixups); |
| unsigned Size = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups); |
| |
| return Position + Size - 1; |
| } |
| |
| #include "MipsGenMCCodeEmitter.inc" |
| |