| //===-- R600EmitClauseMarkers.cpp - Emit CF_ALU ---------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| /// \file |
| /// Add CF_ALU. R600 Alu instructions are grouped in clause which can hold |
| /// 128 Alu instructions ; these instructions can access up to 4 prefetched |
| /// 4 lines of 16 registers from constant buffers. Such ALU clauses are |
| /// initiated by CF_ALU instructions. |
| //===----------------------------------------------------------------------===// |
| |
| #include "AMDGPU.h" |
| #include "R600Defines.h" |
| #include "R600InstrInfo.h" |
| #include "R600MachineFunctionInfo.h" |
| #include "R600RegisterInfo.h" |
| #include "llvm/CodeGen/MachineFunctionPass.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineRegisterInfo.h" |
| |
| namespace llvm { |
| |
| class R600EmitClauseMarkersPass : public MachineFunctionPass { |
| |
| private: |
| static char ID; |
| const R600InstrInfo *TII; |
| |
| unsigned OccupiedDwords(MachineInstr *MI) const { |
| switch (MI->getOpcode()) { |
| case AMDGPU::INTERP_PAIR_XY: |
| case AMDGPU::INTERP_PAIR_ZW: |
| case AMDGPU::INTERP_VEC_LOAD: |
| case AMDGPU::DOT4_eg_pseudo: |
| case AMDGPU::DOT4_r600_pseudo: |
| return 4; |
| case AMDGPU::KILL: |
| return 0; |
| default: |
| break; |
| } |
| |
| if(TII->isVector(*MI) || |
| TII->isCubeOp(MI->getOpcode()) || |
| TII->isReductionOp(MI->getOpcode())) |
| return 4; |
| |
| unsigned NumLiteral = 0; |
| for (MachineInstr::mop_iterator It = MI->operands_begin(), |
| E = MI->operands_end(); It != E; ++It) { |
| MachineOperand &MO = *It; |
| if (MO.isReg() && MO.getReg() == AMDGPU::ALU_LITERAL_X) |
| ++NumLiteral; |
| } |
| return 1 + NumLiteral; |
| } |
| |
| bool isALU(const MachineInstr *MI) const { |
| if (TII->isALUInstr(MI->getOpcode())) |
| return true; |
| if (TII->isVector(*MI) || TII->isCubeOp(MI->getOpcode())) |
| return true; |
| switch (MI->getOpcode()) { |
| case AMDGPU::PRED_X: |
| case AMDGPU::INTERP_PAIR_XY: |
| case AMDGPU::INTERP_PAIR_ZW: |
| case AMDGPU::INTERP_VEC_LOAD: |
| case AMDGPU::COPY: |
| case AMDGPU::DOT4_eg_pseudo: |
| case AMDGPU::DOT4_r600_pseudo: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| bool IsTrivialInst(MachineInstr *MI) const { |
| switch (MI->getOpcode()) { |
| case AMDGPU::KILL: |
| case AMDGPU::RETURN: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| // Register Idx, then Const value |
| std::vector<std::pair<unsigned, unsigned> > ExtractConstRead(MachineInstr *MI) |
| const { |
| const R600Operands::Ops OpTable[3][2] = { |
| {R600Operands::SRC0, R600Operands::SRC0_SEL}, |
| {R600Operands::SRC1, R600Operands::SRC1_SEL}, |
| {R600Operands::SRC2, R600Operands::SRC2_SEL}, |
| }; |
| std::vector<std::pair<unsigned, unsigned> > Result; |
| |
| if (!TII->isALUInstr(MI->getOpcode())) |
| return Result; |
| for (unsigned j = 0; j < 3; j++) { |
| int SrcIdx = TII->getOperandIdx(MI->getOpcode(), OpTable[j][0]); |
| if (SrcIdx < 0) |
| break; |
| if (MI->getOperand(SrcIdx).getReg() == AMDGPU::ALU_CONST) { |
| unsigned Const = MI->getOperand( |
| TII->getOperandIdx(MI->getOpcode(), OpTable[j][1])).getImm(); |
| Result.push_back(std::pair<unsigned, unsigned>(SrcIdx, Const)); |
| } |
| } |
| return Result; |
| } |
| |
| std::pair<unsigned, unsigned> getAccessedBankLine(unsigned Sel) const { |
| // Sel is (512 + (kc_bank << 12) + ConstIndex) << 2 |
| // (See also R600ISelLowering.cpp) |
| // ConstIndex value is in [0, 4095]; |
| return std::pair<unsigned, unsigned>( |
| ((Sel >> 2) - 512) >> 12, // KC_BANK |
| // Line Number of ConstIndex |
| // A line contains 16 constant registers however KCX bank can lock |
| // two line at the same time ; thus we want to get an even line number. |
| // Line number can be retrieved with (>>4), using (>>5) <<1 generates |
| // an even number. |
| ((((Sel >> 2) - 512) & 4095) >> 5) << 1); |
| } |
| |
| bool SubstituteKCacheBank(MachineInstr *MI, |
| std::vector<std::pair<unsigned, unsigned> > &CachedConsts) const { |
| std::vector<std::pair<unsigned, unsigned> > UsedKCache; |
| std::vector<std::pair<unsigned, unsigned> > Consts = ExtractConstRead(MI); |
| assert(TII->isALUInstr(MI->getOpcode()) && "Can't assign Const"); |
| for (unsigned i = 0, n = Consts.size(); i < n; ++i) { |
| unsigned Sel = Consts[i].second; |
| unsigned Chan = Sel & 3, Index = ((Sel >> 2) - 512) & 31; |
| unsigned KCacheIndex = Index * 4 + Chan; |
| const std::pair<unsigned, unsigned> &BankLine = getAccessedBankLine(Sel); |
| if (CachedConsts.empty()) { |
| CachedConsts.push_back(BankLine); |
| UsedKCache.push_back(std::pair<unsigned, unsigned>(0, KCacheIndex)); |
| continue; |
| } |
| if (CachedConsts[0] == BankLine) { |
| UsedKCache.push_back(std::pair<unsigned, unsigned>(0, KCacheIndex)); |
| continue; |
| } |
| if (CachedConsts.size() == 1) { |
| CachedConsts.push_back(BankLine); |
| UsedKCache.push_back(std::pair<unsigned, unsigned>(1, KCacheIndex)); |
| continue; |
| } |
| if (CachedConsts[1] == BankLine) { |
| UsedKCache.push_back(std::pair<unsigned, unsigned>(1, KCacheIndex)); |
| continue; |
| } |
| return false; |
| } |
| |
| for (unsigned i = 0, n = Consts.size(); i < n; ++i) { |
| switch(UsedKCache[i].first) { |
| case 0: |
| MI->getOperand(Consts[i].first).setReg( |
| AMDGPU::R600_KC0RegClass.getRegister(UsedKCache[i].second)); |
| break; |
| case 1: |
| MI->getOperand(Consts[i].first).setReg( |
| AMDGPU::R600_KC1RegClass.getRegister(UsedKCache[i].second)); |
| break; |
| default: |
| llvm_unreachable("Wrong Cache Line"); |
| } |
| } |
| return true; |
| } |
| |
| MachineBasicBlock::iterator |
| MakeALUClause(MachineBasicBlock &MBB, MachineBasicBlock::iterator I) const { |
| MachineBasicBlock::iterator ClauseHead = I; |
| std::vector<std::pair<unsigned, unsigned> > KCacheBanks; |
| bool PushBeforeModifier = false; |
| unsigned AluInstCount = 0; |
| for (MachineBasicBlock::iterator E = MBB.end(); I != E; ++I) { |
| if (IsTrivialInst(I)) |
| continue; |
| if (!isALU(I)) |
| break; |
| if (AluInstCount > TII->getMaxAlusPerClause()) |
| break; |
| if (I->getOpcode() == AMDGPU::PRED_X) { |
| if (TII->getFlagOp(I).getImm() & MO_FLAG_PUSH) |
| PushBeforeModifier = true; |
| AluInstCount ++; |
| continue; |
| } |
| if (I->getOpcode() == AMDGPU::KILLGT) { |
| I++; |
| break; |
| } |
| if (TII->isALUInstr(I->getOpcode()) && |
| !SubstituteKCacheBank(I, KCacheBanks)) |
| break; |
| AluInstCount += OccupiedDwords(I); |
| } |
| unsigned Opcode = PushBeforeModifier ? |
| AMDGPU::CF_ALU_PUSH_BEFORE : AMDGPU::CF_ALU; |
| BuildMI(MBB, ClauseHead, MBB.findDebugLoc(ClauseHead), TII->get(Opcode)) |
| .addImm(0) // ADDR |
| .addImm(KCacheBanks.empty()?0:KCacheBanks[0].first) // KB0 |
| .addImm((KCacheBanks.size() < 2)?0:KCacheBanks[1].first) // KB1 |
| .addImm(KCacheBanks.empty()?0:2) // KM0 |
| .addImm((KCacheBanks.size() < 2)?0:2) // KM1 |
| .addImm(KCacheBanks.empty()?0:KCacheBanks[0].second) // KLINE0 |
| .addImm((KCacheBanks.size() < 2)?0:KCacheBanks[1].second) // KLINE1 |
| .addImm(AluInstCount); // COUNT |
| return I; |
| } |
| |
| public: |
| R600EmitClauseMarkersPass(TargetMachine &tm) : MachineFunctionPass(ID), |
| TII (static_cast<const R600InstrInfo *>(tm.getInstrInfo())) { } |
| |
| virtual bool runOnMachineFunction(MachineFunction &MF) { |
| for (MachineFunction::iterator BB = MF.begin(), BB_E = MF.end(); |
| BB != BB_E; ++BB) { |
| MachineBasicBlock &MBB = *BB; |
| MachineBasicBlock::iterator I = MBB.begin(); |
| if (I->getOpcode() == AMDGPU::CF_ALU) |
| continue; // BB was already parsed |
| for (MachineBasicBlock::iterator E = MBB.end(); I != E;) { |
| if (isALU(I)) |
| I = MakeALUClause(MBB, I); |
| else |
| ++I; |
| } |
| } |
| return false; |
| } |
| |
| const char *getPassName() const { |
| return "R600 Emit Clause Markers Pass"; |
| } |
| }; |
| |
| char R600EmitClauseMarkersPass::ID = 0; |
| |
| } |
| |
| |
| llvm::FunctionPass *llvm::createR600EmitClauseMarkers(TargetMachine &TM) { |
| return new R600EmitClauseMarkersPass(TM); |
| } |
| |
