| //===-- SIMCCodeEmitter.cpp - SI Code Emitter -----------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| /// \file |
| /// The SI code emitter produces machine code that can be executed |
| /// directly on the GPU device. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "AMDGPU.h" |
| #include "MCTargetDesc/AMDGPUFixupKinds.h" |
| #include "MCTargetDesc/AMDGPUMCCodeEmitter.h" |
| #include "MCTargetDesc/AMDGPUMCTargetDesc.h" |
| #include "Utils/AMDGPUBaseInfo.h" |
| #include "llvm/MC/MCCodeEmitter.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCFixup.h" |
| #include "llvm/MC/MCInst.h" |
| #include "llvm/MC/MCInstrDesc.h" |
| #include "llvm/MC/MCInstrInfo.h" |
| #include "llvm/MC/MCRegisterInfo.h" |
| #include "llvm/MC/MCSubtargetInfo.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/Support/Casting.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/MathExtras.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <cassert> |
| #include <cstdint> |
| #include <cstdlib> |
| |
| using namespace llvm; |
| |
| namespace { |
| |
| class SIMCCodeEmitter : public AMDGPUMCCodeEmitter { |
| const MCRegisterInfo &MRI; |
| |
| /// Encode an fp or int literal |
| uint32_t getLitEncoding(const MCOperand &MO, const MCOperandInfo &OpInfo, |
| const MCSubtargetInfo &STI) const; |
| |
| public: |
| SIMCCodeEmitter(const MCInstrInfo &mcii, const MCRegisterInfo &mri, |
| MCContext &ctx) |
| : AMDGPUMCCodeEmitter(mcii), MRI(mri) {} |
| SIMCCodeEmitter(const SIMCCodeEmitter &) = delete; |
| SIMCCodeEmitter &operator=(const SIMCCodeEmitter &) = delete; |
| |
| /// Encode the instruction and write it to the OS. |
| void encodeInstruction(const MCInst &MI, raw_ostream &OS, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const override; |
| |
| /// \returns the encoding for an MCOperand. |
| uint64_t getMachineOpValue(const MCInst &MI, const MCOperand &MO, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const override; |
| |
| /// Use a fixup to encode the simm16 field for SOPP branch |
| /// instructions. |
| unsigned getSOPPBrEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const override; |
| |
| unsigned getSDWASrcEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const override; |
| |
| unsigned getSDWAVopcDstEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const override; |
| }; |
| |
| } // end anonymous namespace |
| |
| MCCodeEmitter *llvm::createSIMCCodeEmitter(const MCInstrInfo &MCII, |
| const MCRegisterInfo &MRI, |
| MCContext &Ctx) { |
| return new SIMCCodeEmitter(MCII, MRI, Ctx); |
| } |
| |
| // Returns the encoding value to use if the given integer is an integer inline |
| // immediate value, or 0 if it is not. |
| template <typename IntTy> |
| static uint32_t getIntInlineImmEncoding(IntTy Imm) { |
| if (Imm >= 0 && Imm <= 64) |
| return 128 + Imm; |
| |
| if (Imm >= -16 && Imm <= -1) |
| return 192 + std::abs(Imm); |
| |
| return 0; |
| } |
| |
| static uint32_t getLit16Encoding(uint16_t Val, const MCSubtargetInfo &STI) { |
| uint16_t IntImm = getIntInlineImmEncoding(static_cast<int16_t>(Val)); |
| if (IntImm != 0) |
| return IntImm; |
| |
| if (Val == 0x3800) // 0.5 |
| return 240; |
| |
| if (Val == 0xB800) // -0.5 |
| return 241; |
| |
| if (Val == 0x3C00) // 1.0 |
| return 242; |
| |
| if (Val == 0xBC00) // -1.0 |
| return 243; |
| |
| if (Val == 0x4000) // 2.0 |
| return 244; |
| |
| if (Val == 0xC000) // -2.0 |
| return 245; |
| |
| if (Val == 0x4400) // 4.0 |
| return 246; |
| |
| if (Val == 0xC400) // -4.0 |
| return 247; |
| |
| if (Val == 0x3118 && // 1.0 / (2.0 * pi) |
| STI.getFeatureBits()[AMDGPU::FeatureInv2PiInlineImm]) |
| return 248; |
| |
| return 255; |
| } |
| |
| static uint32_t getLit32Encoding(uint32_t Val, const MCSubtargetInfo &STI) { |
| uint32_t IntImm = getIntInlineImmEncoding(static_cast<int32_t>(Val)); |
| if (IntImm != 0) |
| return IntImm; |
| |
| if (Val == FloatToBits(0.5f)) |
| return 240; |
| |
| if (Val == FloatToBits(-0.5f)) |
| return 241; |
| |
| if (Val == FloatToBits(1.0f)) |
| return 242; |
| |
| if (Val == FloatToBits(-1.0f)) |
| return 243; |
| |
| if (Val == FloatToBits(2.0f)) |
| return 244; |
| |
| if (Val == FloatToBits(-2.0f)) |
| return 245; |
| |
| if (Val == FloatToBits(4.0f)) |
| return 246; |
| |
| if (Val == FloatToBits(-4.0f)) |
| return 247; |
| |
| if (Val == 0x3e22f983 && // 1.0 / (2.0 * pi) |
| STI.getFeatureBits()[AMDGPU::FeatureInv2PiInlineImm]) |
| return 248; |
| |
| return 255; |
| } |
| |
| static uint32_t getLit64Encoding(uint64_t Val, const MCSubtargetInfo &STI) { |
| uint32_t IntImm = getIntInlineImmEncoding(static_cast<int64_t>(Val)); |
| if (IntImm != 0) |
| return IntImm; |
| |
| if (Val == DoubleToBits(0.5)) |
| return 240; |
| |
| if (Val == DoubleToBits(-0.5)) |
| return 241; |
| |
| if (Val == DoubleToBits(1.0)) |
| return 242; |
| |
| if (Val == DoubleToBits(-1.0)) |
| return 243; |
| |
| if (Val == DoubleToBits(2.0)) |
| return 244; |
| |
| if (Val == DoubleToBits(-2.0)) |
| return 245; |
| |
| if (Val == DoubleToBits(4.0)) |
| return 246; |
| |
| if (Val == DoubleToBits(-4.0)) |
| return 247; |
| |
| if (Val == 0x3fc45f306dc9c882 && // 1.0 / (2.0 * pi) |
| STI.getFeatureBits()[AMDGPU::FeatureInv2PiInlineImm]) |
| return 248; |
| |
| return 255; |
| } |
| |
| uint32_t SIMCCodeEmitter::getLitEncoding(const MCOperand &MO, |
| const MCOperandInfo &OpInfo, |
| const MCSubtargetInfo &STI) const { |
| int64_t Imm; |
| if (MO.isExpr()) { |
| const auto *C = dyn_cast<MCConstantExpr>(MO.getExpr()); |
| if (!C) |
| return 255; |
| |
| Imm = C->getValue(); |
| } else { |
| |
| assert(!MO.isFPImm()); |
| |
| if (!MO.isImm()) |
| return ~0; |
| |
| Imm = MO.getImm(); |
| } |
| |
| switch (OpInfo.OperandType) { |
| case AMDGPU::OPERAND_REG_IMM_INT32: |
| case AMDGPU::OPERAND_REG_IMM_FP32: |
| case AMDGPU::OPERAND_REG_INLINE_C_INT32: |
| case AMDGPU::OPERAND_REG_INLINE_C_FP32: |
| return getLit32Encoding(static_cast<uint32_t>(Imm), STI); |
| |
| case AMDGPU::OPERAND_REG_IMM_INT64: |
| case AMDGPU::OPERAND_REG_IMM_FP64: |
| case AMDGPU::OPERAND_REG_INLINE_C_INT64: |
| case AMDGPU::OPERAND_REG_INLINE_C_FP64: |
| return getLit64Encoding(static_cast<uint64_t>(Imm), STI); |
| |
| case AMDGPU::OPERAND_REG_IMM_INT16: |
| case AMDGPU::OPERAND_REG_IMM_FP16: |
| case AMDGPU::OPERAND_REG_INLINE_C_INT16: |
| case AMDGPU::OPERAND_REG_INLINE_C_FP16: |
| // FIXME Is this correct? What do inline immediates do on SI for f16 src |
| // which does not have f16 support? |
| return getLit16Encoding(static_cast<uint16_t>(Imm), STI); |
| |
| case AMDGPU::OPERAND_REG_INLINE_C_V2INT16: |
| case AMDGPU::OPERAND_REG_INLINE_C_V2FP16: { |
| uint16_t Lo16 = static_cast<uint16_t>(Imm); |
| uint32_t Encoding = getLit16Encoding(Lo16, STI); |
| return Encoding; |
| } |
| default: |
| llvm_unreachable("invalid operand size"); |
| } |
| } |
| |
| void SIMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const { |
| verifyInstructionPredicates(MI, |
| computeAvailableFeatures(STI.getFeatureBits())); |
| |
| uint64_t Encoding = getBinaryCodeForInstr(MI, Fixups, STI); |
| const MCInstrDesc &Desc = MCII.get(MI.getOpcode()); |
| unsigned bytes = Desc.getSize(); |
| |
| for (unsigned i = 0; i < bytes; i++) { |
| OS.write((uint8_t) ((Encoding >> (8 * i)) & 0xff)); |
| } |
| |
| if (bytes > 4) |
| return; |
| |
| // Check for additional literals in SRC0/1/2 (Op 1/2/3) |
| for (unsigned i = 0, e = Desc.getNumOperands(); i < e; ++i) { |
| |
| // Check if this operand should be encoded as [SV]Src |
| if (!AMDGPU::isSISrcOperand(Desc, i)) |
| continue; |
| |
| // Is this operand a literal immediate? |
| const MCOperand &Op = MI.getOperand(i); |
| if (getLitEncoding(Op, Desc.OpInfo[i], STI) != 255) |
| continue; |
| |
| // Yes! Encode it |
| int64_t Imm = 0; |
| |
| if (Op.isImm()) |
| Imm = Op.getImm(); |
| else if (Op.isExpr()) { |
| if (const auto *C = dyn_cast<MCConstantExpr>(Op.getExpr())) |
| Imm = C->getValue(); |
| |
| } else if (!Op.isExpr()) // Exprs will be replaced with a fixup value. |
| llvm_unreachable("Must be immediate or expr"); |
| |
| for (unsigned j = 0; j < 4; j++) { |
| OS.write((uint8_t) ((Imm >> (8 * j)) & 0xff)); |
| } |
| |
| // Only one literal value allowed |
| break; |
| } |
| } |
| |
| unsigned SIMCCodeEmitter::getSOPPBrEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const { |
| const MCOperand &MO = MI.getOperand(OpNo); |
| |
| if (MO.isExpr()) { |
| const MCExpr *Expr = MO.getExpr(); |
| MCFixupKind Kind = (MCFixupKind)AMDGPU::fixup_si_sopp_br; |
| Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc())); |
| return 0; |
| } |
| |
| return getMachineOpValue(MI, MO, Fixups, STI); |
| } |
| |
| unsigned |
| SIMCCodeEmitter::getSDWASrcEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const { |
| using namespace AMDGPU::SDWA; |
| |
| uint64_t RegEnc = 0; |
| |
| const MCOperand &MO = MI.getOperand(OpNo); |
| |
| if (MO.isReg()) { |
| unsigned Reg = MO.getReg(); |
| RegEnc |= MRI.getEncodingValue(Reg); |
| RegEnc &= SDWA9EncValues::SRC_VGPR_MASK; |
| if (AMDGPU::isSGPR(AMDGPU::mc2PseudoReg(Reg), &MRI)) { |
| RegEnc |= SDWA9EncValues::SRC_SGPR_MASK; |
| } |
| return RegEnc; |
| } else { |
| const MCInstrDesc &Desc = MCII.get(MI.getOpcode()); |
| uint32_t Enc = getLitEncoding(MO, Desc.OpInfo[OpNo], STI); |
| if (Enc != ~0U && Enc != 255) { |
| return Enc | SDWA9EncValues::SRC_SGPR_MASK; |
| } |
| } |
| |
| llvm_unreachable("Unsupported operand kind"); |
| return 0; |
| } |
| |
| unsigned |
| SIMCCodeEmitter::getSDWAVopcDstEncoding(const MCInst &MI, unsigned OpNo, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const { |
| using namespace AMDGPU::SDWA; |
| |
| uint64_t RegEnc = 0; |
| |
| const MCOperand &MO = MI.getOperand(OpNo); |
| |
| unsigned Reg = MO.getReg(); |
| if (Reg != AMDGPU::VCC) { |
| RegEnc |= MRI.getEncodingValue(Reg); |
| RegEnc &= SDWA9EncValues::VOPC_DST_SGPR_MASK; |
| RegEnc |= SDWA9EncValues::VOPC_DST_VCC_MASK; |
| } |
| return RegEnc; |
| } |
| |
| static bool needsPCRel(const MCExpr *Expr) { |
| switch (Expr->getKind()) { |
| case MCExpr::SymbolRef: |
| return true; |
| case MCExpr::Binary: { |
| auto *BE = cast<MCBinaryExpr>(Expr); |
| if (BE->getOpcode() == MCBinaryExpr::Sub) |
| return false; |
| return needsPCRel(BE->getLHS()) || needsPCRel(BE->getRHS()); |
| } |
| case MCExpr::Unary: |
| return needsPCRel(cast<MCUnaryExpr>(Expr)->getSubExpr()); |
| case MCExpr::Target: |
| case MCExpr::Constant: |
| return false; |
| } |
| llvm_unreachable("invalid kind"); |
| } |
| |
| uint64_t SIMCCodeEmitter::getMachineOpValue(const MCInst &MI, |
| const MCOperand &MO, |
| SmallVectorImpl<MCFixup> &Fixups, |
| const MCSubtargetInfo &STI) const { |
| if (MO.isReg()) |
| return MRI.getEncodingValue(MO.getReg()); |
| |
| if (MO.isExpr() && MO.getExpr()->getKind() != MCExpr::Constant) { |
| // FIXME: If this is expression is PCRel or not should not depend on what |
| // the expression looks like. Given that this is just a general expression, |
| // it should probably be FK_Data_4 and whatever is producing |
| // |
| // s_add_u32 s2, s2, (extern_const_addrspace+16 |
| // |
| // And expecting a PCRel should instead produce |
| // |
| // .Ltmp1: |
| // s_add_u32 s2, s2, (extern_const_addrspace+16)-.Ltmp1 |
| MCFixupKind Kind; |
| if (needsPCRel(MO.getExpr())) |
| Kind = FK_PCRel_4; |
| else |
| Kind = FK_Data_4; |
| Fixups.push_back(MCFixup::create(4, MO.getExpr(), Kind, MI.getLoc())); |
| } |
| |
| // Figure out the operand number, needed for isSrcOperand check |
| unsigned OpNo = 0; |
| for (unsigned e = MI.getNumOperands(); OpNo < e; ++OpNo) { |
| if (&MO == &MI.getOperand(OpNo)) |
| break; |
| } |
| |
| const MCInstrDesc &Desc = MCII.get(MI.getOpcode()); |
| if (AMDGPU::isSISrcOperand(Desc, OpNo)) { |
| uint32_t Enc = getLitEncoding(MO, Desc.OpInfo[OpNo], STI); |
| if (Enc != ~0U && (Enc != 255 || Desc.getSize() == 4)) |
| return Enc; |
| |
| } else if (MO.isImm()) |
| return MO.getImm(); |
| |
| llvm_unreachable("Encoding of this operand type is not supported yet."); |
| return 0; |
| } |
| |
| #define ENABLE_INSTR_PREDICATE_VERIFIER |
| #include "AMDGPUGenMCCodeEmitter.inc" |