//===- R600MCCodeEmitter.cpp - Code Emitter for R600->Cayman GPU families -===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This code emitters outputs bytecode that is understood by the r600g driver // in the Mesa [1] project. The bytecode is very similar to the hardware's ISA, // except that the size of the instruction fields are rounded up to the // nearest byte. // // [1] http://www.mesa3d.org/ // //===----------------------------------------------------------------------===// #include "R600Defines.h" #include "MCTargetDesc/AMDGPUMCTargetDesc.h" #include "MCTargetDesc/AMDGPUMCCodeEmitter.h" #include "llvm/MC/MCCodeEmitter.h" #include "llvm/MC/MCContext.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" #include <stdio.h> #define SRC_BYTE_COUNT 11 #define DST_BYTE_COUNT 5 using namespace llvm; namespace { class R600MCCodeEmitter : public AMDGPUMCCodeEmitter { R600MCCodeEmitter(const R600MCCodeEmitter &); // DO NOT IMPLEMENT void operator=(const R600MCCodeEmitter &); // DO NOT IMPLEMENT const MCInstrInfo &MCII; const MCSubtargetInfo &STI; MCContext &Ctx; public: R600MCCodeEmitter(const MCInstrInfo &mcii, const MCSubtargetInfo &sti, MCContext &ctx) : MCII(mcii), STI(sti), Ctx(ctx) { } /// EncodeInstruction - Encode the instruction and write it to the OS. virtual void EncodeInstruction(const MCInst &MI, raw_ostream &OS, SmallVectorImpl<MCFixup> &Fixups) const; /// getMachineOpValue - Reutrn the encoding for an MCOperand. virtual uint64_t getMachineOpValue(const MCInst &MI, const MCOperand &MO, SmallVectorImpl<MCFixup> &Fixups) const; private: void EmitALUInstr(const MCInst &MI, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const; void EmitSrc(const MCInst &MI, unsigned OpIdx, raw_ostream &OS) const; void EmitDst(const MCInst &MI, raw_ostream &OS) const; void EmitALU(const MCInst &MI, unsigned numSrc, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const; void EmitTexInstr(const MCInst &MI, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const; void EmitFCInstr(const MCInst &MI, raw_ostream &OS) const; void EmitNullBytes(unsigned int byteCount, raw_ostream &OS) const; void EmitByte(unsigned int byte, raw_ostream &OS) const; void EmitTwoBytes(uint32_t bytes, raw_ostream &OS) const; void Emit(uint32_t value, raw_ostream &OS) const; void Emit(uint64_t value, raw_ostream &OS) const; unsigned getHWRegIndex(unsigned reg) const; unsigned getHWRegChan(unsigned reg) const; unsigned getHWReg(unsigned regNo) const; bool isFCOp(unsigned opcode) const; bool isTexOp(unsigned opcode) const; bool isFlagSet(const MCInst &MI, unsigned Operand, unsigned Flag) const; /// getHWRegIndexGen - Get the register's hardware index. Implemented in /// R600HwRegInfo.include. unsigned getHWRegIndexGen(unsigned int Reg) const; /// getHWRegChanGen - Get the register's channel. Implemented in /// R600HwRegInfo.include. unsigned getHWRegChanGen(unsigned int Reg) const; }; } // End anonymous namespace enum RegElement { ELEMENT_X = 0, ELEMENT_Y, ELEMENT_Z, ELEMENT_W }; enum InstrTypes { INSTR_ALU = 0, INSTR_TEX, INSTR_FC, INSTR_NATIVE, INSTR_VTX }; enum FCInstr { FC_IF = 0, FC_IF_INT, FC_ELSE, FC_ENDIF, FC_BGNLOOP, FC_ENDLOOP, FC_BREAK, FC_BREAK_NZ_INT, FC_CONTINUE, FC_BREAK_Z_INT, FC_BREAK_NZ }; enum TextureTypes { TEXTURE_1D = 1, TEXTURE_2D, TEXTURE_3D, TEXTURE_CUBE, TEXTURE_RECT, TEXTURE_SHADOW1D, TEXTURE_SHADOW2D, TEXTURE_SHADOWRECT, TEXTURE_1D_ARRAY, TEXTURE_2D_ARRAY, TEXTURE_SHADOW1D_ARRAY, TEXTURE_SHADOW2D_ARRAY }; MCCodeEmitter *llvm::createR600MCCodeEmitter(const MCInstrInfo &MCII, const MCSubtargetInfo &STI, MCContext &Ctx) { return new R600MCCodeEmitter(MCII, STI, Ctx); } void R600MCCodeEmitter::EncodeInstruction(const MCInst &MI, raw_ostream &OS, SmallVectorImpl<MCFixup> &Fixups) const { if (isTexOp(MI.getOpcode())) { EmitTexInstr(MI, Fixups, OS); } else if (isFCOp(MI.getOpcode())){ EmitFCInstr(MI, OS); } else if (MI.getOpcode() == AMDGPU::RETURN || MI.getOpcode() == AMDGPU::BUNDLE || MI.getOpcode() == AMDGPU::KILL) { return; } else { switch(MI.getOpcode()) { case AMDGPU::RAT_WRITE_CACHELESS_eg: { uint64_t inst = getBinaryCodeForInstr(MI, Fixups); EmitByte(INSTR_NATIVE, OS); Emit(inst, OS); break; } case AMDGPU::VTX_READ_PARAM_i32_eg: case AMDGPU::VTX_READ_PARAM_f32_eg: case AMDGPU::VTX_READ_GLOBAL_i32_eg: case AMDGPU::VTX_READ_GLOBAL_f32_eg: case AMDGPU::VTX_READ_GLOBAL_v4i32_eg: case AMDGPU::VTX_READ_GLOBAL_v4f32_eg: { uint64_t InstWord01 = getBinaryCodeForInstr(MI, Fixups); uint32_t InstWord2 = MI.getOperand(2).getImm(); // Offset EmitByte(INSTR_VTX, OS); Emit(InstWord01, OS); Emit(InstWord2, OS); break; } default: EmitALUInstr(MI, Fixups, OS); break; } } } void R600MCCodeEmitter::EmitALUInstr(const MCInst &MI, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const { const MCInstrDesc &MCDesc = MCII.get(MI.getOpcode()); unsigned NumOperands = MI.getNumOperands(); if(MCDesc.findFirstPredOperandIdx() > -1) NumOperands--; if (GET_FLAG_OPERAND_IDX(MCDesc.TSFlags) != 0) NumOperands--; if(MI.getOpcode() == AMDGPU::PRED_X) NumOperands = 2; // XXX Check if instruction writes a result if (NumOperands < 1) { return; } // Emit instruction type EmitByte(0, OS); unsigned int OpIndex; for (OpIndex = 1; OpIndex < NumOperands; OpIndex++) { // Literal constants are always stored as the last operand. if (MI.getOperand(OpIndex).isImm() || MI.getOperand(OpIndex).isFPImm()) { break; } EmitSrc(MI, OpIndex, OS); } // Emit zeros for unused sources for ( ; OpIndex < 4; OpIndex++) { EmitNullBytes(SRC_BYTE_COUNT, OS); } EmitDst(MI, OS); EmitALU(MI, NumOperands - 1, Fixups, OS); } void R600MCCodeEmitter::EmitSrc(const MCInst &MI, unsigned OpIdx, raw_ostream &OS) const { const MCOperand &MO = MI.getOperand(OpIdx); union { float f; uint32_t i; } Value; Value.i = 0; // Emit the source select (2 bytes). For GPRs, this is the register index. // For other potential instruction operands, (e.g. constant registers) the // value of the source select is defined in the r600isa docs. if (MO.isReg()) { unsigned reg = MO.getReg(); EmitTwoBytes(getHWReg(reg), OS); if (reg == AMDGPU::ALU_LITERAL_X) { unsigned ImmOpIndex = MI.getNumOperands() - 1; MCOperand ImmOp = MI.getOperand(ImmOpIndex); if (ImmOp.isFPImm()) { Value.f = ImmOp.getFPImm(); } else { assert(ImmOp.isImm()); Value.i = ImmOp.getImm(); } } } else { // XXX: Handle other operand types. EmitTwoBytes(0, OS); } // Emit the source channel (1 byte) if (MO.isReg()) { EmitByte(getHWRegChan(MO.getReg()), OS); } else { EmitByte(0, OS); } // XXX: Emit isNegated (1 byte) if ((!(isFlagSet(MI, OpIdx, MO_FLAG_ABS))) && (isFlagSet(MI, OpIdx, MO_FLAG_NEG) || (MO.isReg() && (MO.getReg() == AMDGPU::NEG_ONE || MO.getReg() == AMDGPU::NEG_HALF)))){ EmitByte(1, OS); } else { EmitByte(0, OS); } // Emit isAbsolute (1 byte) if (isFlagSet(MI, OpIdx, MO_FLAG_ABS)) { EmitByte(1, OS); } else { EmitByte(0, OS); } // XXX: Emit relative addressing mode (1 byte) EmitByte(0, OS); // Emit kc_bank, This will be adjusted later by r600_asm EmitByte(0, OS); // Emit the literal value, if applicable (4 bytes). Emit(Value.i, OS); } void R600MCCodeEmitter::EmitDst(const MCInst &MI, raw_ostream &OS) const { const MCOperand &MO = MI.getOperand(0); if (MO.isReg() && MO.getReg() != AMDGPU::PREDICATE_BIT) { // Emit the destination register index (1 byte) EmitByte(getHWReg(MO.getReg()), OS); // Emit the element of the destination register (1 byte) EmitByte(getHWRegChan(MO.getReg()), OS); // Emit isClamped (1 byte) if (isFlagSet(MI, 0, MO_FLAG_CLAMP)) { EmitByte(1, OS); } else { EmitByte(0, OS); } // Emit writemask (1 byte). if (isFlagSet(MI, 0, MO_FLAG_MASK)) { EmitByte(0, OS); } else { EmitByte(1, OS); } // XXX: Emit relative addressing mode EmitByte(0, OS); } else { // XXX: Handle other operand types. Are there any for destination regs? EmitNullBytes(DST_BYTE_COUNT, OS); } } void R600MCCodeEmitter::EmitALU(const MCInst &MI, unsigned numSrc, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const { const MCInstrDesc &MCDesc = MCII.get(MI.getOpcode()); // Emit the instruction (2 bytes) EmitTwoBytes(getBinaryCodeForInstr(MI, Fixups), OS); // Emit IsLast (for this instruction group) (1 byte) if (isFlagSet(MI, 0, MO_FLAG_NOT_LAST)) { EmitByte(0, OS); } else { EmitByte(1, OS); } // Emit isOp3 (1 byte) if (numSrc == 3) { EmitByte(1, OS); } else { EmitByte(0, OS); } // XXX: Emit push modifier if(isFlagSet(MI, 1, MO_FLAG_PUSH)) { EmitByte(1, OS); } else { EmitByte(0, OS); } // XXX: Emit predicate (1 byte) int PredIdx = MCDesc.findFirstPredOperandIdx(); if (PredIdx > -1) switch(MI.getOperand(PredIdx).getReg()) { case AMDGPU::PRED_SEL_ZERO: EmitByte(2, OS); break; case AMDGPU::PRED_SEL_ONE: EmitByte(3, OS); break; default: EmitByte(0, OS); break; } else { EmitByte(0, OS); } // XXX: Emit bank swizzle. (1 byte) Do we need this? It looks like // r600_asm.c sets it. EmitByte(0, OS); // XXX: Emit bank_swizzle_force (1 byte) Not sure what this is for. EmitByte(0, OS); // XXX: Emit OMOD (1 byte) Not implemented. EmitByte(0, OS); // XXX: Emit index_mode. I think this is for indirect addressing, so we // don't need to worry about it. EmitByte(0, OS); } void R600MCCodeEmitter::EmitTexInstr(const MCInst &MI, SmallVectorImpl<MCFixup> &Fixups, raw_ostream &OS) const { unsigned opcode = MI.getOpcode(); bool hasOffsets = (opcode == AMDGPU::TEX_LD); unsigned op_offset = hasOffsets ? 3 : 0; int64_t sampler = MI.getOperand(op_offset+2).getImm(); int64_t textureType = MI.getOperand(op_offset+3).getImm(); unsigned srcSelect[4] = {0, 1, 2, 3}; // Emit instruction type EmitByte(1, OS); // Emit instruction EmitByte(getBinaryCodeForInstr(MI, Fixups), OS); // XXX: Emit resource id r600_shader.c uses sampler + 1. Why? EmitByte(sampler + 1 + 1, OS); // Emit source register EmitByte(getHWReg(MI.getOperand(1).getReg()), OS); // XXX: Emit src isRelativeAddress EmitByte(0, OS); // Emit destination register EmitByte(getHWReg(MI.getOperand(0).getReg()), OS); // XXX: Emit dst isRealtiveAddress EmitByte(0, OS); // XXX: Emit dst select EmitByte(0, OS); // X EmitByte(1, OS); // Y EmitByte(2, OS); // Z EmitByte(3, OS); // W // XXX: Emit lod bias EmitByte(0, OS); // XXX: Emit coord types unsigned coordType[4] = {1, 1, 1, 1}; if (textureType == TEXTURE_RECT || textureType == TEXTURE_SHADOWRECT) { coordType[ELEMENT_X] = 0; coordType[ELEMENT_Y] = 0; } if (textureType == TEXTURE_1D_ARRAY || textureType == TEXTURE_SHADOW1D_ARRAY) { if (opcode == AMDGPU::TEX_SAMPLE_C_L || opcode == AMDGPU::TEX_SAMPLE_C_LB) { coordType[ELEMENT_Y] = 0; } else { coordType[ELEMENT_Z] = 0; srcSelect[ELEMENT_Z] = ELEMENT_Y; } } else if (textureType == TEXTURE_2D_ARRAY || textureType == TEXTURE_SHADOW2D_ARRAY) { coordType[ELEMENT_Z] = 0; } for (unsigned i = 0; i < 4; i++) { EmitByte(coordType[i], OS); } // XXX: Emit offsets if (hasOffsets) for (unsigned i = 2; i < 5; i++) EmitByte(MI.getOperand(i).getImm()<<1, OS); else EmitNullBytes(3, OS); // Emit sampler id EmitByte(sampler, OS); // XXX:Emit source select if ((textureType == TEXTURE_SHADOW1D || textureType == TEXTURE_SHADOW2D || textureType == TEXTURE_SHADOWRECT || textureType == TEXTURE_SHADOW1D_ARRAY) && opcode != AMDGPU::TEX_SAMPLE_C_L && opcode != AMDGPU::TEX_SAMPLE_C_LB) { srcSelect[ELEMENT_W] = ELEMENT_Z; } for (unsigned i = 0; i < 4; i++) { EmitByte(srcSelect[i], OS); } } void R600MCCodeEmitter::EmitFCInstr(const MCInst &MI, raw_ostream &OS) const { // Emit instruction type EmitByte(INSTR_FC, OS); // Emit SRC unsigned NumOperands = MI.getNumOperands(); if (NumOperands > 0) { assert(NumOperands == 1); EmitSrc(MI, 0, OS); } else { EmitNullBytes(SRC_BYTE_COUNT, OS); } // Emit FC Instruction enum FCInstr instr; switch (MI.getOpcode()) { case AMDGPU::BREAK_LOGICALZ_f32: instr = FC_BREAK; break; case AMDGPU::BREAK_LOGICALNZ_f32: instr = FC_BREAK_NZ; break; case AMDGPU::BREAK_LOGICALNZ_i32: instr = FC_BREAK_NZ_INT; break; case AMDGPU::BREAK_LOGICALZ_i32: instr = FC_BREAK_Z_INT; break; case AMDGPU::CONTINUE_LOGICALNZ_f32: case AMDGPU::CONTINUE_LOGICALNZ_i32: instr = FC_CONTINUE; break; case AMDGPU::IF_LOGICALNZ_f32: instr = FC_IF; case AMDGPU::IF_LOGICALNZ_i32: instr = FC_IF_INT; break; case AMDGPU::IF_LOGICALZ_f32: abort(); break; case AMDGPU::ELSE: instr = FC_ELSE; break; case AMDGPU::ENDIF: instr = FC_ENDIF; break; case AMDGPU::ENDLOOP: instr = FC_ENDLOOP; break; case AMDGPU::WHILELOOP: instr = FC_BGNLOOP; break; default: abort(); break; } EmitByte(instr, OS); } void R600MCCodeEmitter::EmitNullBytes(unsigned int ByteCount, raw_ostream &OS) const { for (unsigned int i = 0; i < ByteCount; i++) { EmitByte(0, OS); } } void R600MCCodeEmitter::EmitByte(unsigned int Byte, raw_ostream &OS) const { OS.write((uint8_t) Byte & 0xff); } void R600MCCodeEmitter::EmitTwoBytes(unsigned int Bytes, raw_ostream &OS) const { OS.write((uint8_t) (Bytes & 0xff)); OS.write((uint8_t) ((Bytes >> 8) & 0xff)); } void R600MCCodeEmitter::Emit(uint32_t Value, raw_ostream &OS) const { for (unsigned i = 0; i < 4; i++) { OS.write((uint8_t) ((Value >> (8 * i)) & 0xff)); } } void R600MCCodeEmitter::Emit(uint64_t Value, raw_ostream &OS) const { for (unsigned i = 0; i < 8; i++) { EmitByte((Value >> (8 * i)) & 0xff, OS); } } unsigned R600MCCodeEmitter::getHWRegIndex(unsigned reg) const { switch(reg) { case AMDGPU::ZERO: return 248; case AMDGPU::ONE: case AMDGPU::NEG_ONE: return 249; case AMDGPU::ONE_INT: return 250; case AMDGPU::HALF: case AMDGPU::NEG_HALF: return 252; case AMDGPU::ALU_LITERAL_X: return 253; case AMDGPU::PREDICATE_BIT: case AMDGPU::PRED_SEL_OFF: case AMDGPU::PRED_SEL_ZERO: case AMDGPU::PRED_SEL_ONE: return 0; default: return getHWRegIndexGen(reg); } } unsigned R600MCCodeEmitter::getHWRegChan(unsigned reg) const { switch(reg) { case AMDGPU::ZERO: case AMDGPU::ONE: case AMDGPU::ONE_INT: case AMDGPU::NEG_ONE: case AMDGPU::HALF: case AMDGPU::NEG_HALF: case AMDGPU::ALU_LITERAL_X: case AMDGPU::PREDICATE_BIT: case AMDGPU::PRED_SEL_OFF: case AMDGPU::PRED_SEL_ZERO: case AMDGPU::PRED_SEL_ONE: return 0; default: return getHWRegChanGen(reg); } } unsigned R600MCCodeEmitter::getHWReg(unsigned RegNo) const { unsigned HWReg; HWReg = getHWRegIndex(RegNo); if (AMDGPUMCRegisterClasses[AMDGPU::R600_CReg32RegClassID].contains(RegNo)) { HWReg += 512; } return HWReg; } uint64_t R600MCCodeEmitter::getMachineOpValue(const MCInst &MI, const MCOperand &MO, SmallVectorImpl<MCFixup> &Fixup) const { if (MO.isReg()) { return getHWReg(MO.getReg()); } else { return MO.getImm(); } } //===----------------------------------------------------------------------===// // Encoding helper functions //===----------------------------------------------------------------------===// bool R600MCCodeEmitter::isFCOp(unsigned opcode) const { switch(opcode) { default: return false; case AMDGPU::BREAK_LOGICALZ_f32: case AMDGPU::BREAK_LOGICALNZ_i32: case AMDGPU::BREAK_LOGICALZ_i32: case AMDGPU::BREAK_LOGICALNZ_f32: case AMDGPU::CONTINUE_LOGICALNZ_f32: case AMDGPU::IF_LOGICALNZ_i32: case AMDGPU::IF_LOGICALZ_f32: case AMDGPU::ELSE: case AMDGPU::ENDIF: case AMDGPU::ENDLOOP: case AMDGPU::IF_LOGICALNZ_f32: case AMDGPU::WHILELOOP: return true; } } bool R600MCCodeEmitter::isTexOp(unsigned opcode) const { switch(opcode) { default: return false; case AMDGPU::TEX_LD: case AMDGPU::TEX_GET_TEXTURE_RESINFO: case AMDGPU::TEX_SAMPLE: case AMDGPU::TEX_SAMPLE_C: case AMDGPU::TEX_SAMPLE_L: case AMDGPU::TEX_SAMPLE_C_L: case AMDGPU::TEX_SAMPLE_LB: case AMDGPU::TEX_SAMPLE_C_LB: case AMDGPU::TEX_SAMPLE_G: case AMDGPU::TEX_SAMPLE_C_G: case AMDGPU::TEX_GET_GRADIENTS_H: case AMDGPU::TEX_GET_GRADIENTS_V: case AMDGPU::TEX_SET_GRADIENTS_H: case AMDGPU::TEX_SET_GRADIENTS_V: return true; } } bool R600MCCodeEmitter::isFlagSet(const MCInst &MI, unsigned Operand, unsigned Flag) const { const MCInstrDesc &MCDesc = MCII.get(MI.getOpcode()); unsigned FlagIndex = GET_FLAG_OPERAND_IDX(MCDesc.TSFlags); if (FlagIndex == 0) { return false; } assert(MI.getOperand(FlagIndex).isImm()); return !!((MI.getOperand(FlagIndex).getImm() >> (NUM_MO_FLAGS * Operand)) & Flag); } #define R600RegisterInfo R600MCCodeEmitter #include "R600HwRegInfo.include" #undef R600RegisterInfo #include "AMDGPUGenMCCodeEmitter.inc"