//===- llvm/CodeGen/GlobalISel/IRTranslator.cpp - IRTranslator ---*- C++ -*-==// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// /// \file /// This file implements the IRTranslator class. //===----------------------------------------------------------------------===// #include "llvm/CodeGen/GlobalISel/IRTranslator.h" #include "llvm/ADT/PostOrderIterator.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/ScopeExit.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/Analysis/AssumptionCache.h" #include "llvm/Analysis/BranchProbabilityInfo.h" #include "llvm/Analysis/Loads.h" #include "llvm/Analysis/OptimizationRemarkEmitter.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/Analysis/VectorUtils.h" #include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/GlobalISel/CSEInfo.h" #include "llvm/CodeGen/GlobalISel/CSEMIRBuilder.h" #include "llvm/CodeGen/GlobalISel/CallLowering.h" #include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h" #include "llvm/CodeGen/GlobalISel/InlineAsmLowering.h" #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h" #include "llvm/CodeGen/LowLevelTypeUtils.h" #include "llvm/CodeGen/MachineBasicBlock.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineMemOperand.h" #include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/CodeGen/MachineOperand.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/RuntimeLibcallUtil.h" #include "llvm/CodeGen/StackProtector.h" #include "llvm/CodeGen/SwitchLoweringUtils.h" #include "llvm/CodeGen/TargetFrameLowering.h" #include "llvm/CodeGen/TargetInstrInfo.h" #include "llvm/CodeGen/TargetLowering.h" #include "llvm/CodeGen/TargetOpcodes.h" #include "llvm/CodeGen/TargetPassConfig.h" #include "llvm/CodeGen/TargetRegisterInfo.h" #include "llvm/CodeGen/TargetSubtargetInfo.h" #include "llvm/CodeGenTypes/LowLevelType.h" #include "llvm/IR/BasicBlock.h" #include "llvm/IR/CFG.h" #include "llvm/IR/Constant.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/DerivedTypes.h" #include "llvm/IR/DiagnosticInfo.h" #include "llvm/IR/Function.h" #include "llvm/IR/GetElementPtrTypeIterator.h" #include "llvm/IR/InlineAsm.h" #include "llvm/IR/InstrTypes.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Intrinsics.h" #include "llvm/IR/IntrinsicsAMDGPU.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Metadata.h" #include "llvm/IR/PatternMatch.h" #include "llvm/IR/Statepoint.h" #include "llvm/IR/Type.h" #include "llvm/IR/User.h" #include "llvm/IR/Value.h" #include "llvm/InitializePasses.h" #include "llvm/MC/MCContext.h" #include "llvm/Pass.h" #include "llvm/Support/Casting.h" #include "llvm/Support/CodeGen.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/MathExtras.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetIntrinsicInfo.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Transforms/Utils/Local.h" #include "llvm/Transforms/Utils/MemoryOpRemark.h" #include #include #include #include #include #include #include #include #define DEBUG_TYPE "irtranslator" using namespace llvm; static cl::opt EnableCSEInIRTranslator("enable-cse-in-irtranslator", cl::desc("Should enable CSE in irtranslator"), cl::Optional, cl::init(false)); char IRTranslator::ID = 0; INITIALIZE_PASS_BEGIN(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI", false, false) INITIALIZE_PASS_DEPENDENCY(TargetPassConfig) INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass) INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass) INITIALIZE_PASS_DEPENDENCY(StackProtector) INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) INITIALIZE_PASS_END(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI", false, false) static void reportTranslationError(MachineFunction &MF, const TargetPassConfig &TPC, OptimizationRemarkEmitter &ORE, OptimizationRemarkMissed &R) { MF.getProperties().set(MachineFunctionProperties::Property::FailedISel); // Print the function name explicitly if we don't have a debug location (which // makes the diagnostic less useful) or if we're going to emit a raw error. if (!R.getLocation().isValid() || TPC.isGlobalISelAbortEnabled()) R << (" (in function: " + MF.getName() + ")").str(); if (TPC.isGlobalISelAbortEnabled()) report_fatal_error(Twine(R.getMsg())); else ORE.emit(R); } IRTranslator::IRTranslator(CodeGenOptLevel optlevel) : MachineFunctionPass(ID), OptLevel(optlevel) {} #ifndef NDEBUG namespace { /// Verify that every instruction created has the same DILocation as the /// instruction being translated. class DILocationVerifier : public GISelChangeObserver { const Instruction *CurrInst = nullptr; public: DILocationVerifier() = default; ~DILocationVerifier() = default; const Instruction *getCurrentInst() const { return CurrInst; } void setCurrentInst(const Instruction *Inst) { CurrInst = Inst; } void erasingInstr(MachineInstr &MI) override {} void changingInstr(MachineInstr &MI) override {} void changedInstr(MachineInstr &MI) override {} void createdInstr(MachineInstr &MI) override { assert(getCurrentInst() && "Inserted instruction without a current MI"); // Only print the check message if we're actually checking it. #ifndef NDEBUG LLVM_DEBUG(dbgs() << "Checking DILocation from " << *CurrInst << " was copied to " << MI); #endif // We allow insts in the entry block to have no debug loc because // they could have originated from constants, and we don't want a jumpy // debug experience. assert((CurrInst->getDebugLoc() == MI.getDebugLoc() || (MI.getParent()->isEntryBlock() && !MI.getDebugLoc()) || (MI.isDebugInstr())) && "Line info was not transferred to all instructions"); } }; } // namespace #endif // ifndef NDEBUG void IRTranslator::getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequired(); AU.addRequired(); AU.addRequired(); AU.addRequired(); if (OptLevel != CodeGenOptLevel::None) { AU.addRequired(); AU.addRequired(); } AU.addRequired(); AU.addPreserved(); getSelectionDAGFallbackAnalysisUsage(AU); MachineFunctionPass::getAnalysisUsage(AU); } IRTranslator::ValueToVRegInfo::VRegListT & IRTranslator::allocateVRegs(const Value &Val) { auto VRegsIt = VMap.findVRegs(Val); if (VRegsIt != VMap.vregs_end()) return *VRegsIt->second; auto *Regs = VMap.getVRegs(Val); auto *Offsets = VMap.getOffsets(Val); SmallVector SplitTys; computeValueLLTs(*DL, *Val.getType(), SplitTys, Offsets->empty() ? Offsets : nullptr); for (unsigned i = 0; i < SplitTys.size(); ++i) Regs->push_back(0); return *Regs; } ArrayRef IRTranslator::getOrCreateVRegs(const Value &Val) { auto VRegsIt = VMap.findVRegs(Val); if (VRegsIt != VMap.vregs_end()) return *VRegsIt->second; if (Val.getType()->isVoidTy()) return *VMap.getVRegs(Val); // Create entry for this type. auto *VRegs = VMap.getVRegs(Val); auto *Offsets = VMap.getOffsets(Val); if (!Val.getType()->isTokenTy()) assert(Val.getType()->isSized() && "Don't know how to create an empty vreg"); SmallVector SplitTys; computeValueLLTs(*DL, *Val.getType(), SplitTys, Offsets->empty() ? Offsets : nullptr); if (!isa(Val)) { for (auto Ty : SplitTys) VRegs->push_back(MRI->createGenericVirtualRegister(Ty)); return *VRegs; } if (Val.getType()->isAggregateType()) { // UndefValue, ConstantAggregateZero auto &C = cast(Val); unsigned Idx = 0; while (auto Elt = C.getAggregateElement(Idx++)) { auto EltRegs = getOrCreateVRegs(*Elt); llvm::copy(EltRegs, std::back_inserter(*VRegs)); } } else { assert(SplitTys.size() == 1 && "unexpectedly split LLT"); VRegs->push_back(MRI->createGenericVirtualRegister(SplitTys[0])); bool Success = translate(cast(Val), VRegs->front()); if (!Success) { OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", MF->getFunction().getSubprogram(), &MF->getFunction().getEntryBlock()); R << "unable to translate constant: " << ore::NV("Type", Val.getType()); reportTranslationError(*MF, *TPC, *ORE, R); return *VRegs; } } return *VRegs; } int IRTranslator::getOrCreateFrameIndex(const AllocaInst &AI) { auto MapEntry = FrameIndices.find(&AI); if (MapEntry != FrameIndices.end()) return MapEntry->second; uint64_t ElementSize = DL->getTypeAllocSize(AI.getAllocatedType()); uint64_t Size = ElementSize * cast(AI.getArraySize())->getZExtValue(); // Always allocate at least one byte. Size = std::max(Size, 1u); int &FI = FrameIndices[&AI]; FI = MF->getFrameInfo().CreateStackObject(Size, AI.getAlign(), false, &AI); return FI; } Align IRTranslator::getMemOpAlign(const Instruction &I) { if (const StoreInst *SI = dyn_cast(&I)) return SI->getAlign(); if (const LoadInst *LI = dyn_cast(&I)) return LI->getAlign(); if (const AtomicCmpXchgInst *AI = dyn_cast(&I)) return AI->getAlign(); if (const AtomicRMWInst *AI = dyn_cast(&I)) return AI->getAlign(); OptimizationRemarkMissed R("gisel-irtranslator", "", &I); R << "unable to translate memop: " << ore::NV("Opcode", &I); reportTranslationError(*MF, *TPC, *ORE, R); return Align(1); } MachineBasicBlock &IRTranslator::getMBB(const BasicBlock &BB) { MachineBasicBlock *&MBB = BBToMBB[&BB]; assert(MBB && "BasicBlock was not encountered before"); return *MBB; } void IRTranslator::addMachineCFGPred(CFGEdge Edge, MachineBasicBlock *NewPred) { assert(NewPred && "new predecessor must be a real MachineBasicBlock"); MachinePreds[Edge].push_back(NewPred); } bool IRTranslator::translateBinaryOp(unsigned Opcode, const User &U, MachineIRBuilder &MIRBuilder) { // Get or create a virtual register for each value. // Unless the value is a Constant => loadimm cst? // or inline constant each time? // Creation of a virtual register needs to have a size. Register Op0 = getOrCreateVReg(*U.getOperand(0)); Register Op1 = getOrCreateVReg(*U.getOperand(1)); Register Res = getOrCreateVReg(U); uint32_t Flags = 0; if (isa(U)) { const Instruction &I = cast(U); Flags = MachineInstr::copyFlagsFromInstruction(I); } MIRBuilder.buildInstr(Opcode, {Res}, {Op0, Op1}, Flags); return true; } bool IRTranslator::translateUnaryOp(unsigned Opcode, const User &U, MachineIRBuilder &MIRBuilder) { Register Op0 = getOrCreateVReg(*U.getOperand(0)); Register Res = getOrCreateVReg(U); uint32_t Flags = 0; if (isa(U)) { const Instruction &I = cast(U); Flags = MachineInstr::copyFlagsFromInstruction(I); } MIRBuilder.buildInstr(Opcode, {Res}, {Op0}, Flags); return true; } bool IRTranslator::translateFNeg(const User &U, MachineIRBuilder &MIRBuilder) { return translateUnaryOp(TargetOpcode::G_FNEG, U, MIRBuilder); } bool IRTranslator::translateCompare(const User &U, MachineIRBuilder &MIRBuilder) { auto *CI = cast(&U); Register Op0 = getOrCreateVReg(*U.getOperand(0)); Register Op1 = getOrCreateVReg(*U.getOperand(1)); Register Res = getOrCreateVReg(U); CmpInst::Predicate Pred = CI->getPredicate(); if (CmpInst::isIntPredicate(Pred)) MIRBuilder.buildICmp(Pred, Res, Op0, Op1); else if (Pred == CmpInst::FCMP_FALSE) MIRBuilder.buildCopy( Res, getOrCreateVReg(*Constant::getNullValue(U.getType()))); else if (Pred == CmpInst::FCMP_TRUE) MIRBuilder.buildCopy( Res, getOrCreateVReg(*Constant::getAllOnesValue(U.getType()))); else { uint32_t Flags = 0; if (CI) Flags = MachineInstr::copyFlagsFromInstruction(*CI); MIRBuilder.buildFCmp(Pred, Res, Op0, Op1, Flags); } return true; } bool IRTranslator::translateRet(const User &U, MachineIRBuilder &MIRBuilder) { const ReturnInst &RI = cast(U); const Value *Ret = RI.getReturnValue(); if (Ret && DL->getTypeStoreSize(Ret->getType()).isZero()) Ret = nullptr; ArrayRef VRegs; if (Ret) VRegs = getOrCreateVRegs(*Ret); Register SwiftErrorVReg = 0; if (CLI->supportSwiftError() && SwiftError.getFunctionArg()) { SwiftErrorVReg = SwiftError.getOrCreateVRegUseAt( &RI, &MIRBuilder.getMBB(), SwiftError.getFunctionArg()); } // The target may mess up with the insertion point, but // this is not important as a return is the last instruction // of the block anyway. return CLI->lowerReturn(MIRBuilder, Ret, VRegs, FuncInfo, SwiftErrorVReg); } void IRTranslator::emitBranchForMergedCondition( const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB, MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB, BranchProbability TProb, BranchProbability FProb, bool InvertCond) { // If the leaf of the tree is a comparison, merge the condition into // the caseblock. if (const CmpInst *BOp = dyn_cast(Cond)) { CmpInst::Predicate Condition; if (const ICmpInst *IC = dyn_cast(Cond)) { Condition = InvertCond ? IC->getInversePredicate() : IC->getPredicate(); } else { const FCmpInst *FC = cast(Cond); Condition = InvertCond ? FC->getInversePredicate() : FC->getPredicate(); } SwitchCG::CaseBlock CB(Condition, false, BOp->getOperand(0), BOp->getOperand(1), nullptr, TBB, FBB, CurBB, CurBuilder->getDebugLoc(), TProb, FProb); SL->SwitchCases.push_back(CB); return; } // Create a CaseBlock record representing this branch. CmpInst::Predicate Pred = InvertCond ? CmpInst::ICMP_NE : CmpInst::ICMP_EQ; SwitchCG::CaseBlock CB( Pred, false, Cond, ConstantInt::getTrue(MF->getFunction().getContext()), nullptr, TBB, FBB, CurBB, CurBuilder->getDebugLoc(), TProb, FProb); SL->SwitchCases.push_back(CB); } static bool isValInBlock(const Value *V, const BasicBlock *BB) { if (const Instruction *I = dyn_cast(V)) return I->getParent() == BB; return true; } void IRTranslator::findMergedConditions( const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB, MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB, Instruction::BinaryOps Opc, BranchProbability TProb, BranchProbability FProb, bool InvertCond) { using namespace PatternMatch; assert((Opc == Instruction::And || Opc == Instruction::Or) && "Expected Opc to be AND/OR"); // Skip over not part of the tree and remember to invert op and operands at // next level. Value *NotCond; if (match(Cond, m_OneUse(m_Not(m_Value(NotCond)))) && isValInBlock(NotCond, CurBB->getBasicBlock())) { findMergedConditions(NotCond, TBB, FBB, CurBB, SwitchBB, Opc, TProb, FProb, !InvertCond); return; } const Instruction *BOp = dyn_cast(Cond); const Value *BOpOp0, *BOpOp1; // Compute the effective opcode for Cond, taking into account whether it needs // to be inverted, e.g. // and (not (or A, B)), C // gets lowered as // and (and (not A, not B), C) Instruction::BinaryOps BOpc = (Instruction::BinaryOps)0; if (BOp) { BOpc = match(BOp, m_LogicalAnd(m_Value(BOpOp0), m_Value(BOpOp1))) ? Instruction::And : (match(BOp, m_LogicalOr(m_Value(BOpOp0), m_Value(BOpOp1))) ? Instruction::Or : (Instruction::BinaryOps)0); if (InvertCond) { if (BOpc == Instruction::And) BOpc = Instruction::Or; else if (BOpc == Instruction::Or) BOpc = Instruction::And; } } // If this node is not part of the or/and tree, emit it as a branch. // Note that all nodes in the tree should have same opcode. bool BOpIsInOrAndTree = BOpc && BOpc == Opc && BOp->hasOneUse(); if (!BOpIsInOrAndTree || BOp->getParent() != CurBB->getBasicBlock() || !isValInBlock(BOpOp0, CurBB->getBasicBlock()) || !isValInBlock(BOpOp1, CurBB->getBasicBlock())) { emitBranchForMergedCondition(Cond, TBB, FBB, CurBB, SwitchBB, TProb, FProb, InvertCond); return; } // Create TmpBB after CurBB. MachineFunction::iterator BBI(CurBB); MachineBasicBlock *TmpBB = MF->CreateMachineBasicBlock(CurBB->getBasicBlock()); CurBB->getParent()->insert(++BBI, TmpBB); if (Opc == Instruction::Or) { // Codegen X | Y as: // BB1: // jmp_if_X TBB // jmp TmpBB // TmpBB: // jmp_if_Y TBB // jmp FBB // // We have flexibility in setting Prob for BB1 and Prob for TmpBB. // The requirement is that // TrueProb for BB1 + (FalseProb for BB1 * TrueProb for TmpBB) // = TrueProb for original BB. // Assuming the original probabilities are A and B, one choice is to set // BB1's probabilities to A/2 and A/2+B, and set TmpBB's probabilities to // A/(1+B) and 2B/(1+B). This choice assumes that // TrueProb for BB1 == FalseProb for BB1 * TrueProb for TmpBB. // Another choice is to assume TrueProb for BB1 equals to TrueProb for // TmpBB, but the math is more complicated. auto NewTrueProb = TProb / 2; auto NewFalseProb = TProb / 2 + FProb; // Emit the LHS condition. findMergedConditions(BOpOp0, TBB, TmpBB, CurBB, SwitchBB, Opc, NewTrueProb, NewFalseProb, InvertCond); // Normalize A/2 and B to get A/(1+B) and 2B/(1+B). SmallVector Probs{TProb / 2, FProb}; BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end()); // Emit the RHS condition into TmpBB. findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0], Probs[1], InvertCond); } else { assert(Opc == Instruction::And && "Unknown merge op!"); // Codegen X & Y as: // BB1: // jmp_if_X TmpBB // jmp FBB // TmpBB: // jmp_if_Y TBB // jmp FBB // // This requires creation of TmpBB after CurBB. // We have flexibility in setting Prob for BB1 and Prob for TmpBB. // The requirement is that // FalseProb for BB1 + (TrueProb for BB1 * FalseProb for TmpBB) // = FalseProb for original BB. // Assuming the original probabilities are A and B, one choice is to set // BB1's probabilities to A+B/2 and B/2, and set TmpBB's probabilities to // 2A/(1+A) and B/(1+A). This choice assumes that FalseProb for BB1 == // TrueProb for BB1 * FalseProb for TmpBB. auto NewTrueProb = TProb + FProb / 2; auto NewFalseProb = FProb / 2; // Emit the LHS condition. findMergedConditions(BOpOp0, TmpBB, FBB, CurBB, SwitchBB, Opc, NewTrueProb, NewFalseProb, InvertCond); // Normalize A and B/2 to get 2A/(1+A) and B/(1+A). SmallVector Probs{TProb, FProb / 2}; BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end()); // Emit the RHS condition into TmpBB. findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0], Probs[1], InvertCond); } } bool IRTranslator::shouldEmitAsBranches( const std::vector &Cases) { // For multiple cases, it's better to emit as branches. if (Cases.size() != 2) return true; // If this is two comparisons of the same values or'd or and'd together, they // will get folded into a single comparison, so don't emit two blocks. if ((Cases[0].CmpLHS == Cases[1].CmpLHS && Cases[0].CmpRHS == Cases[1].CmpRHS) || (Cases[0].CmpRHS == Cases[1].CmpLHS && Cases[0].CmpLHS == Cases[1].CmpRHS)) { return false; } // Handle: (X != null) | (Y != null) --> (X|Y) != 0 // Handle: (X == null) & (Y == null) --> (X|Y) == 0 if (Cases[0].CmpRHS == Cases[1].CmpRHS && Cases[0].PredInfo.Pred == Cases[1].PredInfo.Pred && isa(Cases[0].CmpRHS) && cast(Cases[0].CmpRHS)->isNullValue()) { if (Cases[0].PredInfo.Pred == CmpInst::ICMP_EQ && Cases[0].TrueBB == Cases[1].ThisBB) return false; if (Cases[0].PredInfo.Pred == CmpInst::ICMP_NE && Cases[0].FalseBB == Cases[1].ThisBB) return false; } return true; } bool IRTranslator::translateBr(const User &U, MachineIRBuilder &MIRBuilder) { const BranchInst &BrInst = cast(U); auto &CurMBB = MIRBuilder.getMBB(); auto *Succ0MBB = &getMBB(*BrInst.getSuccessor(0)); if (BrInst.isUnconditional()) { // If the unconditional target is the layout successor, fallthrough. if (OptLevel == CodeGenOptLevel::None || !CurMBB.isLayoutSuccessor(Succ0MBB)) MIRBuilder.buildBr(*Succ0MBB); // Link successors. for (const BasicBlock *Succ : successors(&BrInst)) CurMBB.addSuccessor(&getMBB(*Succ)); return true; } // If this condition is one of the special cases we handle, do special stuff // now. const Value *CondVal = BrInst.getCondition(); MachineBasicBlock *Succ1MBB = &getMBB(*BrInst.getSuccessor(1)); // If this is a series of conditions that are or'd or and'd together, emit // this as a sequence of branches instead of setcc's with and/or operations. // As long as jumps are not expensive (exceptions for multi-use logic ops, // unpredictable branches, and vector extracts because those jumps are likely // expensive for any target), this should improve performance. // For example, instead of something like: // cmp A, B // C = seteq // cmp D, E // F = setle // or C, F // jnz foo // Emit: // cmp A, B // je foo // cmp D, E // jle foo using namespace PatternMatch; const Instruction *CondI = dyn_cast(CondVal); if (!TLI->isJumpExpensive() && CondI && CondI->hasOneUse() && !BrInst.hasMetadata(LLVMContext::MD_unpredictable)) { Instruction::BinaryOps Opcode = (Instruction::BinaryOps)0; Value *Vec; const Value *BOp0, *BOp1; if (match(CondI, m_LogicalAnd(m_Value(BOp0), m_Value(BOp1)))) Opcode = Instruction::And; else if (match(CondI, m_LogicalOr(m_Value(BOp0), m_Value(BOp1)))) Opcode = Instruction::Or; if (Opcode && !(match(BOp0, m_ExtractElt(m_Value(Vec), m_Value())) && match(BOp1, m_ExtractElt(m_Specific(Vec), m_Value())))) { findMergedConditions(CondI, Succ0MBB, Succ1MBB, &CurMBB, &CurMBB, Opcode, getEdgeProbability(&CurMBB, Succ0MBB), getEdgeProbability(&CurMBB, Succ1MBB), /*InvertCond=*/false); assert(SL->SwitchCases[0].ThisBB == &CurMBB && "Unexpected lowering!"); // Allow some cases to be rejected. if (shouldEmitAsBranches(SL->SwitchCases)) { // Emit the branch for this block. emitSwitchCase(SL->SwitchCases[0], &CurMBB, *CurBuilder); SL->SwitchCases.erase(SL->SwitchCases.begin()); return true; } // Okay, we decided not to do this, remove any inserted MBB's and clear // SwitchCases. for (unsigned I = 1, E = SL->SwitchCases.size(); I != E; ++I) MF->erase(SL->SwitchCases[I].ThisBB); SL->SwitchCases.clear(); } } // Create a CaseBlock record representing this branch. SwitchCG::CaseBlock CB(CmpInst::ICMP_EQ, false, CondVal, ConstantInt::getTrue(MF->getFunction().getContext()), nullptr, Succ0MBB, Succ1MBB, &CurMBB, CurBuilder->getDebugLoc()); // Use emitSwitchCase to actually insert the fast branch sequence for this // cond branch. emitSwitchCase(CB, &CurMBB, *CurBuilder); return true; } void IRTranslator::addSuccessorWithProb(MachineBasicBlock *Src, MachineBasicBlock *Dst, BranchProbability Prob) { if (!FuncInfo.BPI) { Src->addSuccessorWithoutProb(Dst); return; } if (Prob.isUnknown()) Prob = getEdgeProbability(Src, Dst); Src->addSuccessor(Dst, Prob); } BranchProbability IRTranslator::getEdgeProbability(const MachineBasicBlock *Src, const MachineBasicBlock *Dst) const { const BasicBlock *SrcBB = Src->getBasicBlock(); const BasicBlock *DstBB = Dst->getBasicBlock(); if (!FuncInfo.BPI) { // If BPI is not available, set the default probability as 1 / N, where N is // the number of successors. auto SuccSize = std::max(succ_size(SrcBB), 1); return BranchProbability(1, SuccSize); } return FuncInfo.BPI->getEdgeProbability(SrcBB, DstBB); } bool IRTranslator::translateSwitch(const User &U, MachineIRBuilder &MIB) { using namespace SwitchCG; // Extract cases from the switch. const SwitchInst &SI = cast(U); BranchProbabilityInfo *BPI = FuncInfo.BPI; CaseClusterVector Clusters; Clusters.reserve(SI.getNumCases()); for (const auto &I : SI.cases()) { MachineBasicBlock *Succ = &getMBB(*I.getCaseSuccessor()); assert(Succ && "Could not find successor mbb in mapping"); const ConstantInt *CaseVal = I.getCaseValue(); BranchProbability Prob = BPI ? BPI->getEdgeProbability(SI.getParent(), I.getSuccessorIndex()) : BranchProbability(1, SI.getNumCases() + 1); Clusters.push_back(CaseCluster::range(CaseVal, CaseVal, Succ, Prob)); } MachineBasicBlock *DefaultMBB = &getMBB(*SI.getDefaultDest()); // Cluster adjacent cases with the same destination. We do this at all // optimization levels because it's cheap to do and will make codegen faster // if there are many clusters. sortAndRangeify(Clusters); MachineBasicBlock *SwitchMBB = &getMBB(*SI.getParent()); // If there is only the default destination, jump there directly. if (Clusters.empty()) { SwitchMBB->addSuccessor(DefaultMBB); if (DefaultMBB != SwitchMBB->getNextNode()) MIB.buildBr(*DefaultMBB); return true; } SL->findJumpTables(Clusters, &SI, std::nullopt, DefaultMBB, nullptr, nullptr); SL->findBitTestClusters(Clusters, &SI); LLVM_DEBUG({ dbgs() << "Case clusters: "; for (const CaseCluster &C : Clusters) { if (C.Kind == CC_JumpTable) dbgs() << "JT:"; if (C.Kind == CC_BitTests) dbgs() << "BT:"; C.Low->getValue().print(dbgs(), true); if (C.Low != C.High) { dbgs() << '-'; C.High->getValue().print(dbgs(), true); } dbgs() << ' '; } dbgs() << '\n'; }); assert(!Clusters.empty()); SwitchWorkList WorkList; CaseClusterIt First = Clusters.begin(); CaseClusterIt Last = Clusters.end() - 1; auto DefaultProb = getEdgeProbability(SwitchMBB, DefaultMBB); WorkList.push_back({SwitchMBB, First, Last, nullptr, nullptr, DefaultProb}); while (!WorkList.empty()) { SwitchWorkListItem W = WorkList.pop_back_val(); unsigned NumClusters = W.LastCluster - W.FirstCluster + 1; // For optimized builds, lower large range as a balanced binary tree. if (NumClusters > 3 && MF->getTarget().getOptLevel() != CodeGenOptLevel::None && !DefaultMBB->getParent()->getFunction().hasMinSize()) { splitWorkItem(WorkList, W, SI.getCondition(), SwitchMBB, MIB); continue; } if (!lowerSwitchWorkItem(W, SI.getCondition(), SwitchMBB, DefaultMBB, MIB)) return false; } return true; } void IRTranslator::splitWorkItem(SwitchCG::SwitchWorkList &WorkList, const SwitchCG::SwitchWorkListItem &W, Value *Cond, MachineBasicBlock *SwitchMBB, MachineIRBuilder &MIB) { using namespace SwitchCG; assert(W.FirstCluster->Low->getValue().slt(W.LastCluster->Low->getValue()) && "Clusters not sorted?"); assert(W.LastCluster - W.FirstCluster + 1 >= 2 && "Too small to split!"); auto [LastLeft, FirstRight, LeftProb, RightProb] = SL->computeSplitWorkItemInfo(W); // Use the first element on the right as pivot since we will make less-than // comparisons against it. CaseClusterIt PivotCluster = FirstRight; assert(PivotCluster > W.FirstCluster); assert(PivotCluster <= W.LastCluster); CaseClusterIt FirstLeft = W.FirstCluster; CaseClusterIt LastRight = W.LastCluster; const ConstantInt *Pivot = PivotCluster->Low; // New blocks will be inserted immediately after the current one. MachineFunction::iterator BBI(W.MBB); ++BBI; // We will branch to the LHS if Value < Pivot. If LHS is a single cluster, // we can branch to its destination directly if it's squeezed exactly in // between the known lower bound and Pivot - 1. MachineBasicBlock *LeftMBB; if (FirstLeft == LastLeft && FirstLeft->Kind == CC_Range && FirstLeft->Low == W.GE && (FirstLeft->High->getValue() + 1LL) == Pivot->getValue()) { LeftMBB = FirstLeft->MBB; } else { LeftMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock()); FuncInfo.MF->insert(BBI, LeftMBB); WorkList.push_back( {LeftMBB, FirstLeft, LastLeft, W.GE, Pivot, W.DefaultProb / 2}); } // Similarly, we will branch to the RHS if Value >= Pivot. If RHS is a // single cluster, RHS.Low == Pivot, and we can branch to its destination // directly if RHS.High equals the current upper bound. MachineBasicBlock *RightMBB; if (FirstRight == LastRight && FirstRight->Kind == CC_Range && W.LT && (FirstRight->High->getValue() + 1ULL) == W.LT->getValue()) { RightMBB = FirstRight->MBB; } else { RightMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock()); FuncInfo.MF->insert(BBI, RightMBB); WorkList.push_back( {RightMBB, FirstRight, LastRight, Pivot, W.LT, W.DefaultProb / 2}); } // Create the CaseBlock record that will be used to lower the branch. CaseBlock CB(ICmpInst::Predicate::ICMP_SLT, false, Cond, Pivot, nullptr, LeftMBB, RightMBB, W.MBB, MIB.getDebugLoc(), LeftProb, RightProb); if (W.MBB == SwitchMBB) emitSwitchCase(CB, SwitchMBB, MIB); else SL->SwitchCases.push_back(CB); } void IRTranslator::emitJumpTable(SwitchCG::JumpTable &JT, MachineBasicBlock *MBB) { // Emit the code for the jump table assert(JT.Reg != -1U && "Should lower JT Header first!"); MachineIRBuilder MIB(*MBB->getParent()); MIB.setMBB(*MBB); MIB.setDebugLoc(CurBuilder->getDebugLoc()); Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext()); const LLT PtrTy = getLLTForType(*PtrIRTy, *DL); auto Table = MIB.buildJumpTable(PtrTy, JT.JTI); MIB.buildBrJT(Table.getReg(0), JT.JTI, JT.Reg); } bool IRTranslator::emitJumpTableHeader(SwitchCG::JumpTable &JT, SwitchCG::JumpTableHeader &JTH, MachineBasicBlock *HeaderBB) { MachineIRBuilder MIB(*HeaderBB->getParent()); MIB.setMBB(*HeaderBB); MIB.setDebugLoc(CurBuilder->getDebugLoc()); const Value &SValue = *JTH.SValue; // Subtract the lowest switch case value from the value being switched on. const LLT SwitchTy = getLLTForType(*SValue.getType(), *DL); Register SwitchOpReg = getOrCreateVReg(SValue); auto FirstCst = MIB.buildConstant(SwitchTy, JTH.First); auto Sub = MIB.buildSub({SwitchTy}, SwitchOpReg, FirstCst); // This value may be smaller or larger than the target's pointer type, and // therefore require extension or truncating. auto *PtrIRTy = PointerType::getUnqual(SValue.getContext()); const LLT PtrScalarTy = LLT::scalar(DL->getTypeSizeInBits(PtrIRTy)); Sub = MIB.buildZExtOrTrunc(PtrScalarTy, Sub); JT.Reg = Sub.getReg(0); if (JTH.FallthroughUnreachable) { if (JT.MBB != HeaderBB->getNextNode()) MIB.buildBr(*JT.MBB); return true; } // Emit the range check for the jump table, and branch to the default block // for the switch statement if the value being switched on exceeds the // largest case in the switch. auto Cst = getOrCreateVReg( *ConstantInt::get(SValue.getType(), JTH.Last - JTH.First)); Cst = MIB.buildZExtOrTrunc(PtrScalarTy, Cst).getReg(0); auto Cmp = MIB.buildICmp(CmpInst::ICMP_UGT, LLT::scalar(1), Sub, Cst); auto BrCond = MIB.buildBrCond(Cmp.getReg(0), *JT.Default); // Avoid emitting unnecessary branches to the next block. if (JT.MBB != HeaderBB->getNextNode()) BrCond = MIB.buildBr(*JT.MBB); return true; } void IRTranslator::emitSwitchCase(SwitchCG::CaseBlock &CB, MachineBasicBlock *SwitchBB, MachineIRBuilder &MIB) { Register CondLHS = getOrCreateVReg(*CB.CmpLHS); Register Cond; DebugLoc OldDbgLoc = MIB.getDebugLoc(); MIB.setDebugLoc(CB.DbgLoc); MIB.setMBB(*CB.ThisBB); if (CB.PredInfo.NoCmp) { // Branch or fall through to TrueBB. addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb); addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()}, CB.ThisBB); CB.ThisBB->normalizeSuccProbs(); if (CB.TrueBB != CB.ThisBB->getNextNode()) MIB.buildBr(*CB.TrueBB); MIB.setDebugLoc(OldDbgLoc); return; } const LLT i1Ty = LLT::scalar(1); // Build the compare. if (!CB.CmpMHS) { const auto *CI = dyn_cast(CB.CmpRHS); // For conditional branch lowering, we might try to do something silly like // emit an G_ICMP to compare an existing G_ICMP i1 result with true. If so, // just re-use the existing condition vreg. if (MRI->getType(CondLHS).getSizeInBits() == 1 && CI && CI->isOne() && CB.PredInfo.Pred == CmpInst::ICMP_EQ) { Cond = CondLHS; } else { Register CondRHS = getOrCreateVReg(*CB.CmpRHS); if (CmpInst::isFPPredicate(CB.PredInfo.Pred)) Cond = MIB.buildFCmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0); else Cond = MIB.buildICmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0); } } else { assert(CB.PredInfo.Pred == CmpInst::ICMP_SLE && "Can only handle SLE ranges"); const APInt& Low = cast(CB.CmpLHS)->getValue(); const APInt& High = cast(CB.CmpRHS)->getValue(); Register CmpOpReg = getOrCreateVReg(*CB.CmpMHS); if (cast(CB.CmpLHS)->isMinValue(true)) { Register CondRHS = getOrCreateVReg(*CB.CmpRHS); Cond = MIB.buildICmp(CmpInst::ICMP_SLE, i1Ty, CmpOpReg, CondRHS).getReg(0); } else { const LLT CmpTy = MRI->getType(CmpOpReg); auto Sub = MIB.buildSub({CmpTy}, CmpOpReg, CondLHS); auto Diff = MIB.buildConstant(CmpTy, High - Low); Cond = MIB.buildICmp(CmpInst::ICMP_ULE, i1Ty, Sub, Diff).getReg(0); } } // Update successor info addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb); addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()}, CB.ThisBB); // TrueBB and FalseBB are always different unless the incoming IR is // degenerate. This only happens when running llc on weird IR. if (CB.TrueBB != CB.FalseBB) addSuccessorWithProb(CB.ThisBB, CB.FalseBB, CB.FalseProb); CB.ThisBB->normalizeSuccProbs(); addMachineCFGPred({SwitchBB->getBasicBlock(), CB.FalseBB->getBasicBlock()}, CB.ThisBB); MIB.buildBrCond(Cond, *CB.TrueBB); MIB.buildBr(*CB.FalseBB); MIB.setDebugLoc(OldDbgLoc); } bool IRTranslator::lowerJumpTableWorkItem(SwitchCG::SwitchWorkListItem W, MachineBasicBlock *SwitchMBB, MachineBasicBlock *CurMBB, MachineBasicBlock *DefaultMBB, MachineIRBuilder &MIB, MachineFunction::iterator BBI, BranchProbability UnhandledProbs, SwitchCG::CaseClusterIt I, MachineBasicBlock *Fallthrough, bool FallthroughUnreachable) { using namespace SwitchCG; MachineFunction *CurMF = SwitchMBB->getParent(); // FIXME: Optimize away range check based on pivot comparisons. JumpTableHeader *JTH = &SL->JTCases[I->JTCasesIndex].first; SwitchCG::JumpTable *JT = &SL->JTCases[I->JTCasesIndex].second; BranchProbability DefaultProb = W.DefaultProb; // The jump block hasn't been inserted yet; insert it here. MachineBasicBlock *JumpMBB = JT->MBB; CurMF->insert(BBI, JumpMBB); // Since the jump table block is separate from the switch block, we need // to keep track of it as a machine predecessor to the default block, // otherwise we lose the phi edges. addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()}, CurMBB); addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()}, JumpMBB); auto JumpProb = I->Prob; auto FallthroughProb = UnhandledProbs; // If the default statement is a target of the jump table, we evenly // distribute the default probability to successors of CurMBB. Also // update the probability on the edge from JumpMBB to Fallthrough. for (MachineBasicBlock::succ_iterator SI = JumpMBB->succ_begin(), SE = JumpMBB->succ_end(); SI != SE; ++SI) { if (*SI == DefaultMBB) { JumpProb += DefaultProb / 2; FallthroughProb -= DefaultProb / 2; JumpMBB->setSuccProbability(SI, DefaultProb / 2); JumpMBB->normalizeSuccProbs(); } else { // Also record edges from the jump table block to it's successors. addMachineCFGPred({SwitchMBB->getBasicBlock(), (*SI)->getBasicBlock()}, JumpMBB); } } if (FallthroughUnreachable) JTH->FallthroughUnreachable = true; if (!JTH->FallthroughUnreachable) addSuccessorWithProb(CurMBB, Fallthrough, FallthroughProb); addSuccessorWithProb(CurMBB, JumpMBB, JumpProb); CurMBB->normalizeSuccProbs(); // The jump table header will be inserted in our current block, do the // range check, and fall through to our fallthrough block. JTH->HeaderBB = CurMBB; JT->Default = Fallthrough; // FIXME: Move Default to JumpTableHeader. // If we're in the right place, emit the jump table header right now. if (CurMBB == SwitchMBB) { if (!emitJumpTableHeader(*JT, *JTH, CurMBB)) return false; JTH->Emitted = true; } return true; } bool IRTranslator::lowerSwitchRangeWorkItem(SwitchCG::CaseClusterIt I, Value *Cond, MachineBasicBlock *Fallthrough, bool FallthroughUnreachable, BranchProbability UnhandledProbs, MachineBasicBlock *CurMBB, MachineIRBuilder &MIB, MachineBasicBlock *SwitchMBB) { using namespace SwitchCG; const Value *RHS, *LHS, *MHS; CmpInst::Predicate Pred; if (I->Low == I->High) { // Check Cond == I->Low. Pred = CmpInst::ICMP_EQ; LHS = Cond; RHS = I->Low; MHS = nullptr; } else { // Check I->Low <= Cond <= I->High. Pred = CmpInst::ICMP_SLE; LHS = I->Low; MHS = Cond; RHS = I->High; } // If Fallthrough is unreachable, fold away the comparison. // The false probability is the sum of all unhandled cases. CaseBlock CB(Pred, FallthroughUnreachable, LHS, RHS, MHS, I->MBB, Fallthrough, CurMBB, MIB.getDebugLoc(), I->Prob, UnhandledProbs); emitSwitchCase(CB, SwitchMBB, MIB); return true; } void IRTranslator::emitBitTestHeader(SwitchCG::BitTestBlock &B, MachineBasicBlock *SwitchBB) { MachineIRBuilder &MIB = *CurBuilder; MIB.setMBB(*SwitchBB); // Subtract the minimum value. Register SwitchOpReg = getOrCreateVReg(*B.SValue); LLT SwitchOpTy = MRI->getType(SwitchOpReg); Register MinValReg = MIB.buildConstant(SwitchOpTy, B.First).getReg(0); auto RangeSub = MIB.buildSub(SwitchOpTy, SwitchOpReg, MinValReg); Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext()); const LLT PtrTy = getLLTForType(*PtrIRTy, *DL); LLT MaskTy = SwitchOpTy; if (MaskTy.getSizeInBits() > PtrTy.getSizeInBits() || !llvm::has_single_bit(MaskTy.getSizeInBits())) MaskTy = LLT::scalar(PtrTy.getSizeInBits()); else { // Ensure that the type will fit the mask value. for (unsigned I = 0, E = B.Cases.size(); I != E; ++I) { if (!isUIntN(SwitchOpTy.getSizeInBits(), B.Cases[I].Mask)) { // Switch table case range are encoded into series of masks. // Just use pointer type, it's guaranteed to fit. MaskTy = LLT::scalar(PtrTy.getSizeInBits()); break; } } } Register SubReg = RangeSub.getReg(0); if (SwitchOpTy != MaskTy) SubReg = MIB.buildZExtOrTrunc(MaskTy, SubReg).getReg(0); B.RegVT = getMVTForLLT(MaskTy); B.Reg = SubReg; MachineBasicBlock *MBB = B.Cases[0].ThisBB; if (!B.FallthroughUnreachable) addSuccessorWithProb(SwitchBB, B.Default, B.DefaultProb); addSuccessorWithProb(SwitchBB, MBB, B.Prob); SwitchBB->normalizeSuccProbs(); if (!B.FallthroughUnreachable) { // Conditional branch to the default block. auto RangeCst = MIB.buildConstant(SwitchOpTy, B.Range); auto RangeCmp = MIB.buildICmp(CmpInst::Predicate::ICMP_UGT, LLT::scalar(1), RangeSub, RangeCst); MIB.buildBrCond(RangeCmp, *B.Default); } // Avoid emitting unnecessary branches to the next block. if (MBB != SwitchBB->getNextNode()) MIB.buildBr(*MBB); } void IRTranslator::emitBitTestCase(SwitchCG::BitTestBlock &BB, MachineBasicBlock *NextMBB, BranchProbability BranchProbToNext, Register Reg, SwitchCG::BitTestCase &B, MachineBasicBlock *SwitchBB) { MachineIRBuilder &MIB = *CurBuilder; MIB.setMBB(*SwitchBB); LLT SwitchTy = getLLTForMVT(BB.RegVT); Register Cmp; unsigned PopCount = llvm::popcount(B.Mask); if (PopCount == 1) { // Testing for a single bit; just compare the shift count with what it // would need to be to shift a 1 bit in that position. auto MaskTrailingZeros = MIB.buildConstant(SwitchTy, llvm::countr_zero(B.Mask)); Cmp = MIB.buildICmp(ICmpInst::ICMP_EQ, LLT::scalar(1), Reg, MaskTrailingZeros) .getReg(0); } else if (PopCount == BB.Range) { // There is only one zero bit in the range, test for it directly. auto MaskTrailingOnes = MIB.buildConstant(SwitchTy, llvm::countr_one(B.Mask)); Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Reg, MaskTrailingOnes) .getReg(0); } else { // Make desired shift. auto CstOne = MIB.buildConstant(SwitchTy, 1); auto SwitchVal = MIB.buildShl(SwitchTy, CstOne, Reg); // Emit bit tests and jumps. auto CstMask = MIB.buildConstant(SwitchTy, B.Mask); auto AndOp = MIB.buildAnd(SwitchTy, SwitchVal, CstMask); auto CstZero = MIB.buildConstant(SwitchTy, 0); Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), AndOp, CstZero) .getReg(0); } // The branch probability from SwitchBB to B.TargetBB is B.ExtraProb. addSuccessorWithProb(SwitchBB, B.TargetBB, B.ExtraProb); // The branch probability from SwitchBB to NextMBB is BranchProbToNext. addSuccessorWithProb(SwitchBB, NextMBB, BranchProbToNext); // It is not guaranteed that the sum of B.ExtraProb and BranchProbToNext is // one as they are relative probabilities (and thus work more like weights), // and hence we need to normalize them to let the sum of them become one. SwitchBB->normalizeSuccProbs(); // Record the fact that the IR edge from the header to the bit test target // will go through our new block. Neeeded for PHIs to have nodes added. addMachineCFGPred({BB.Parent->getBasicBlock(), B.TargetBB->getBasicBlock()}, SwitchBB); MIB.buildBrCond(Cmp, *B.TargetBB); // Avoid emitting unnecessary branches to the next block. if (NextMBB != SwitchBB->getNextNode()) MIB.buildBr(*NextMBB); } bool IRTranslator::lowerBitTestWorkItem( SwitchCG::SwitchWorkListItem W, MachineBasicBlock *SwitchMBB, MachineBasicBlock *CurMBB, MachineBasicBlock *DefaultMBB, MachineIRBuilder &MIB, MachineFunction::iterator BBI, BranchProbability DefaultProb, BranchProbability UnhandledProbs, SwitchCG::CaseClusterIt I, MachineBasicBlock *Fallthrough, bool FallthroughUnreachable) { using namespace SwitchCG; MachineFunction *CurMF = SwitchMBB->getParent(); // FIXME: Optimize away range check based on pivot comparisons. BitTestBlock *BTB = &SL->BitTestCases[I->BTCasesIndex]; // The bit test blocks haven't been inserted yet; insert them here. for (BitTestCase &BTC : BTB->Cases) CurMF->insert(BBI, BTC.ThisBB); // Fill in fields of the BitTestBlock. BTB->Parent = CurMBB; BTB->Default = Fallthrough; BTB->DefaultProb = UnhandledProbs; // If the cases in bit test don't form a contiguous range, we evenly // distribute the probability on the edge to Fallthrough to two // successors of CurMBB. if (!BTB->ContiguousRange) { BTB->Prob += DefaultProb / 2; BTB->DefaultProb -= DefaultProb / 2; } if (FallthroughUnreachable) BTB->FallthroughUnreachable = true; // If we're in the right place, emit the bit test header right now. if (CurMBB == SwitchMBB) { emitBitTestHeader(*BTB, SwitchMBB); BTB->Emitted = true; } return true; } bool IRTranslator::lowerSwitchWorkItem(SwitchCG::SwitchWorkListItem W, Value *Cond, MachineBasicBlock *SwitchMBB, MachineBasicBlock *DefaultMBB, MachineIRBuilder &MIB) { using namespace SwitchCG; MachineFunction *CurMF = FuncInfo.MF; MachineBasicBlock *NextMBB = nullptr; MachineFunction::iterator BBI(W.MBB); if (++BBI != FuncInfo.MF->end()) NextMBB = &*BBI; if (EnableOpts) { // Here, we order cases by probability so the most likely case will be // checked first. However, two clusters can have the same probability in // which case their relative ordering is non-deterministic. So we use Low // as a tie-breaker as clusters are guaranteed to never overlap. llvm::sort(W.FirstCluster, W.LastCluster + 1, [](const CaseCluster &a, const CaseCluster &b) { return a.Prob != b.Prob ? a.Prob > b.Prob : a.Low->getValue().slt(b.Low->getValue()); }); // Rearrange the case blocks so that the last one falls through if possible // without changing the order of probabilities. for (CaseClusterIt I = W.LastCluster; I > W.FirstCluster;) { --I; if (I->Prob > W.LastCluster->Prob) break; if (I->Kind == CC_Range && I->MBB == NextMBB) { std::swap(*I, *W.LastCluster); break; } } } // Compute total probability. BranchProbability DefaultProb = W.DefaultProb; BranchProbability UnhandledProbs = DefaultProb; for (CaseClusterIt I = W.FirstCluster; I <= W.LastCluster; ++I) UnhandledProbs += I->Prob; MachineBasicBlock *CurMBB = W.MBB; for (CaseClusterIt I = W.FirstCluster, E = W.LastCluster; I <= E; ++I) { bool FallthroughUnreachable = false; MachineBasicBlock *Fallthrough; if (I == W.LastCluster) { // For the last cluster, fall through to the default destination. Fallthrough = DefaultMBB; FallthroughUnreachable = isa( DefaultMBB->getBasicBlock()->getFirstNonPHIOrDbg()); } else { Fallthrough = CurMF->CreateMachineBasicBlock(CurMBB->getBasicBlock()); CurMF->insert(BBI, Fallthrough); } UnhandledProbs -= I->Prob; switch (I->Kind) { case CC_BitTests: { if (!lowerBitTestWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI, DefaultProb, UnhandledProbs, I, Fallthrough, FallthroughUnreachable)) { LLVM_DEBUG(dbgs() << "Failed to lower bit test for switch"); return false; } break; } case CC_JumpTable: { if (!lowerJumpTableWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI, UnhandledProbs, I, Fallthrough, FallthroughUnreachable)) { LLVM_DEBUG(dbgs() << "Failed to lower jump table"); return false; } break; } case CC_Range: { if (!lowerSwitchRangeWorkItem(I, Cond, Fallthrough, FallthroughUnreachable, UnhandledProbs, CurMBB, MIB, SwitchMBB)) { LLVM_DEBUG(dbgs() << "Failed to lower switch range"); return false; } break; } } CurMBB = Fallthrough; } return true; } bool IRTranslator::translateIndirectBr(const User &U, MachineIRBuilder &MIRBuilder) { const IndirectBrInst &BrInst = cast(U); const Register Tgt = getOrCreateVReg(*BrInst.getAddress()); MIRBuilder.buildBrIndirect(Tgt); // Link successors. SmallPtrSet AddedSuccessors; MachineBasicBlock &CurBB = MIRBuilder.getMBB(); for (const BasicBlock *Succ : successors(&BrInst)) { // It's legal for indirectbr instructions to have duplicate blocks in the // destination list. We don't allow this in MIR. Skip anything that's // already a successor. if (!AddedSuccessors.insert(Succ).second) continue; CurBB.addSuccessor(&getMBB(*Succ)); } return true; } static bool isSwiftError(const Value *V) { if (auto Arg = dyn_cast(V)) return Arg->hasSwiftErrorAttr(); if (auto AI = dyn_cast(V)) return AI->isSwiftError(); return false; } bool IRTranslator::translateLoad(const User &U, MachineIRBuilder &MIRBuilder) { const LoadInst &LI = cast(U); TypeSize StoreSize = DL->getTypeStoreSize(LI.getType()); if (StoreSize.isZero()) return true; ArrayRef Regs = getOrCreateVRegs(LI); ArrayRef Offsets = *VMap.getOffsets(LI); Register Base = getOrCreateVReg(*LI.getPointerOperand()); AAMDNodes AAInfo = LI.getAAMetadata(); const Value *Ptr = LI.getPointerOperand(); Type *OffsetIRTy = DL->getIndexType(Ptr->getType()); LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL); if (CLI->supportSwiftError() && isSwiftError(Ptr)) { assert(Regs.size() == 1 && "swifterror should be single pointer"); Register VReg = SwiftError.getOrCreateVRegUseAt(&LI, &MIRBuilder.getMBB(), Ptr); MIRBuilder.buildCopy(Regs[0], VReg); return true; } MachineMemOperand::Flags Flags = TLI->getLoadMemOperandFlags(LI, *DL, AC, LibInfo); if (AA && !(Flags & MachineMemOperand::MOInvariant)) { if (AA->pointsToConstantMemory( MemoryLocation(Ptr, LocationSize::precise(StoreSize), AAInfo))) { Flags |= MachineMemOperand::MOInvariant; } } const MDNode *Ranges = Regs.size() == 1 ? LI.getMetadata(LLVMContext::MD_range) : nullptr; for (unsigned i = 0; i < Regs.size(); ++i) { Register Addr; MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8); MachinePointerInfo Ptr(LI.getPointerOperand(), Offsets[i] / 8); Align BaseAlign = getMemOpAlign(LI); auto MMO = MF->getMachineMemOperand( Ptr, Flags, MRI->getType(Regs[i]), commonAlignment(BaseAlign, Offsets[i] / 8), AAInfo, Ranges, LI.getSyncScopeID(), LI.getOrdering()); MIRBuilder.buildLoad(Regs[i], Addr, *MMO); } return true; } bool IRTranslator::translateStore(const User &U, MachineIRBuilder &MIRBuilder) { const StoreInst &SI = cast(U); if (DL->getTypeStoreSize(SI.getValueOperand()->getType()).isZero()) return true; ArrayRef Vals = getOrCreateVRegs(*SI.getValueOperand()); ArrayRef Offsets = *VMap.getOffsets(*SI.getValueOperand()); Register Base = getOrCreateVReg(*SI.getPointerOperand()); Type *OffsetIRTy = DL->getIndexType(SI.getPointerOperandType()); LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL); if (CLI->supportSwiftError() && isSwiftError(SI.getPointerOperand())) { assert(Vals.size() == 1 && "swifterror should be single pointer"); Register VReg = SwiftError.getOrCreateVRegDefAt(&SI, &MIRBuilder.getMBB(), SI.getPointerOperand()); MIRBuilder.buildCopy(VReg, Vals[0]); return true; } MachineMemOperand::Flags Flags = TLI->getStoreMemOperandFlags(SI, *DL); for (unsigned i = 0; i < Vals.size(); ++i) { Register Addr; MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8); MachinePointerInfo Ptr(SI.getPointerOperand(), Offsets[i] / 8); Align BaseAlign = getMemOpAlign(SI); auto MMO = MF->getMachineMemOperand( Ptr, Flags, MRI->getType(Vals[i]), commonAlignment(BaseAlign, Offsets[i] / 8), SI.getAAMetadata(), nullptr, SI.getSyncScopeID(), SI.getOrdering()); MIRBuilder.buildStore(Vals[i], Addr, *MMO); } return true; } static uint64_t getOffsetFromIndices(const User &U, const DataLayout &DL) { const Value *Src = U.getOperand(0); Type *Int32Ty = Type::getInt32Ty(U.getContext()); // getIndexedOffsetInType is designed for GEPs, so the first index is the // usual array element rather than looking into the actual aggregate. SmallVector Indices; Indices.push_back(ConstantInt::get(Int32Ty, 0)); if (const ExtractValueInst *EVI = dyn_cast(&U)) { for (auto Idx : EVI->indices()) Indices.push_back(ConstantInt::get(Int32Ty, Idx)); } else if (const InsertValueInst *IVI = dyn_cast(&U)) { for (auto Idx : IVI->indices()) Indices.push_back(ConstantInt::get(Int32Ty, Idx)); } else { for (unsigned i = 1; i < U.getNumOperands(); ++i) Indices.push_back(U.getOperand(i)); } return 8 * static_cast( DL.getIndexedOffsetInType(Src->getType(), Indices)); } bool IRTranslator::translateExtractValue(const User &U, MachineIRBuilder &MIRBuilder) { const Value *Src = U.getOperand(0); uint64_t Offset = getOffsetFromIndices(U, *DL); ArrayRef SrcRegs = getOrCreateVRegs(*Src); ArrayRef Offsets = *VMap.getOffsets(*Src); unsigned Idx = llvm::lower_bound(Offsets, Offset) - Offsets.begin(); auto &DstRegs = allocateVRegs(U); for (unsigned i = 0; i < DstRegs.size(); ++i) DstRegs[i] = SrcRegs[Idx++]; return true; } bool IRTranslator::translateInsertValue(const User &U, MachineIRBuilder &MIRBuilder) { const Value *Src = U.getOperand(0); uint64_t Offset = getOffsetFromIndices(U, *DL); auto &DstRegs = allocateVRegs(U); ArrayRef DstOffsets = *VMap.getOffsets(U); ArrayRef SrcRegs = getOrCreateVRegs(*Src); ArrayRef InsertedRegs = getOrCreateVRegs(*U.getOperand(1)); auto *InsertedIt = InsertedRegs.begin(); for (unsigned i = 0; i < DstRegs.size(); ++i) { if (DstOffsets[i] >= Offset && InsertedIt != InsertedRegs.end()) DstRegs[i] = *InsertedIt++; else DstRegs[i] = SrcRegs[i]; } return true; } bool IRTranslator::translateSelect(const User &U, MachineIRBuilder &MIRBuilder) { Register Tst = getOrCreateVReg(*U.getOperand(0)); ArrayRef ResRegs = getOrCreateVRegs(U); ArrayRef Op0Regs = getOrCreateVRegs(*U.getOperand(1)); ArrayRef Op1Regs = getOrCreateVRegs(*U.getOperand(2)); uint32_t Flags = 0; if (const SelectInst *SI = dyn_cast(&U)) Flags = MachineInstr::copyFlagsFromInstruction(*SI); for (unsigned i = 0; i < ResRegs.size(); ++i) { MIRBuilder.buildSelect(ResRegs[i], Tst, Op0Regs[i], Op1Regs[i], Flags); } return true; } bool IRTranslator::translateCopy(const User &U, const Value &V, MachineIRBuilder &MIRBuilder) { Register Src = getOrCreateVReg(V); auto &Regs = *VMap.getVRegs(U); if (Regs.empty()) { Regs.push_back(Src); VMap.getOffsets(U)->push_back(0); } else { // If we already assigned a vreg for this instruction, we can't change that. // Emit a copy to satisfy the users we already emitted. MIRBuilder.buildCopy(Regs[0], Src); } return true; } bool IRTranslator::translateBitCast(const User &U, MachineIRBuilder &MIRBuilder) { // If we're bitcasting to the source type, we can reuse the source vreg. if (getLLTForType(*U.getOperand(0)->getType(), *DL) == getLLTForType(*U.getType(), *DL)) { // If the source is a ConstantInt then it was probably created by // ConstantHoisting and we should leave it alone. if (isa(U.getOperand(0))) return translateCast(TargetOpcode::G_CONSTANT_FOLD_BARRIER, U, MIRBuilder); return translateCopy(U, *U.getOperand(0), MIRBuilder); } return translateCast(TargetOpcode::G_BITCAST, U, MIRBuilder); } bool IRTranslator::translateCast(unsigned Opcode, const User &U, MachineIRBuilder &MIRBuilder) { if (U.getType()->getScalarType()->isBFloatTy() || U.getOperand(0)->getType()->getScalarType()->isBFloatTy()) return false; uint32_t Flags = 0; if (const Instruction *I = dyn_cast(&U)) Flags = MachineInstr::copyFlagsFromInstruction(*I); Register Op = getOrCreateVReg(*U.getOperand(0)); Register Res = getOrCreateVReg(U); MIRBuilder.buildInstr(Opcode, {Res}, {Op}, Flags); return true; } bool IRTranslator::translateGetElementPtr(const User &U, MachineIRBuilder &MIRBuilder) { Value &Op0 = *U.getOperand(0); Register BaseReg = getOrCreateVReg(Op0); Type *PtrIRTy = Op0.getType(); LLT PtrTy = getLLTForType(*PtrIRTy, *DL); Type *OffsetIRTy = DL->getIndexType(PtrIRTy); LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL); uint32_t Flags = 0; if (const Instruction *I = dyn_cast(&U)) Flags = MachineInstr::copyFlagsFromInstruction(*I); // Normalize Vector GEP - all scalar operands should be converted to the // splat vector. unsigned VectorWidth = 0; // True if we should use a splat vector; using VectorWidth alone is not // sufficient. bool WantSplatVector = false; if (auto *VT = dyn_cast(U.getType())) { VectorWidth = cast(VT)->getNumElements(); // We don't produce 1 x N vectors; those are treated as scalars. WantSplatVector = VectorWidth > 1; } // We might need to splat the base pointer into a vector if the offsets // are vectors. if (WantSplatVector && !PtrTy.isVector()) { BaseReg = MIRBuilder .buildSplatBuildVector(LLT::fixed_vector(VectorWidth, PtrTy), BaseReg) .getReg(0); PtrIRTy = FixedVectorType::get(PtrIRTy, VectorWidth); PtrTy = getLLTForType(*PtrIRTy, *DL); OffsetIRTy = DL->getIndexType(PtrIRTy); OffsetTy = getLLTForType(*OffsetIRTy, *DL); } int64_t Offset = 0; for (gep_type_iterator GTI = gep_type_begin(&U), E = gep_type_end(&U); GTI != E; ++GTI) { const Value *Idx = GTI.getOperand(); if (StructType *StTy = GTI.getStructTypeOrNull()) { unsigned Field = cast(Idx)->getUniqueInteger().getZExtValue(); Offset += DL->getStructLayout(StTy)->getElementOffset(Field); continue; } else { uint64_t ElementSize = GTI.getSequentialElementStride(*DL); // If this is a scalar constant or a splat vector of constants, // handle it quickly. if (const auto *CI = dyn_cast(Idx)) { if (std::optional Val = CI->getValue().trySExtValue()) { Offset += ElementSize * *Val; continue; } } if (Offset != 0) { auto OffsetMIB = MIRBuilder.buildConstant({OffsetTy}, Offset); BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, OffsetMIB.getReg(0)) .getReg(0); Offset = 0; } Register IdxReg = getOrCreateVReg(*Idx); LLT IdxTy = MRI->getType(IdxReg); if (IdxTy != OffsetTy) { if (!IdxTy.isVector() && WantSplatVector) { IdxReg = MIRBuilder .buildSplatBuildVector(OffsetTy.changeElementType(IdxTy), IdxReg) .getReg(0); } IdxReg = MIRBuilder.buildSExtOrTrunc(OffsetTy, IdxReg).getReg(0); } // N = N + Idx * ElementSize; // Avoid doing it for ElementSize of 1. Register GepOffsetReg; if (ElementSize != 1) { auto ElementSizeMIB = MIRBuilder.buildConstant( getLLTForType(*OffsetIRTy, *DL), ElementSize); GepOffsetReg = MIRBuilder.buildMul(OffsetTy, IdxReg, ElementSizeMIB).getReg(0); } else GepOffsetReg = IdxReg; BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, GepOffsetReg).getReg(0); } } if (Offset != 0) { auto OffsetMIB = MIRBuilder.buildConstant(OffsetTy, Offset); if (int64_t(Offset) >= 0 && cast(U).isInBounds()) Flags |= MachineInstr::MIFlag::NoUWrap; MIRBuilder.buildPtrAdd(getOrCreateVReg(U), BaseReg, OffsetMIB.getReg(0), Flags); return true; } MIRBuilder.buildCopy(getOrCreateVReg(U), BaseReg); return true; } bool IRTranslator::translateMemFunc(const CallInst &CI, MachineIRBuilder &MIRBuilder, unsigned Opcode) { const Value *SrcPtr = CI.getArgOperand(1); // If the source is undef, then just emit a nop. if (isa(SrcPtr)) return true; SmallVector SrcRegs; unsigned MinPtrSize = UINT_MAX; for (auto AI = CI.arg_begin(), AE = CI.arg_end(); std::next(AI) != AE; ++AI) { Register SrcReg = getOrCreateVReg(**AI); LLT SrcTy = MRI->getType(SrcReg); if (SrcTy.isPointer()) MinPtrSize = std::min(SrcTy.getSizeInBits(), MinPtrSize); SrcRegs.push_back(SrcReg); } LLT SizeTy = LLT::scalar(MinPtrSize); // The size operand should be the minimum of the pointer sizes. Register &SizeOpReg = SrcRegs[SrcRegs.size() - 1]; if (MRI->getType(SizeOpReg) != SizeTy) SizeOpReg = MIRBuilder.buildZExtOrTrunc(SizeTy, SizeOpReg).getReg(0); auto ICall = MIRBuilder.buildInstr(Opcode); for (Register SrcReg : SrcRegs) ICall.addUse(SrcReg); Align DstAlign; Align SrcAlign; unsigned IsVol = cast(CI.getArgOperand(CI.arg_size() - 1))->getZExtValue(); ConstantInt *CopySize = nullptr; if (auto *MCI = dyn_cast(&CI)) { DstAlign = MCI->getDestAlign().valueOrOne(); SrcAlign = MCI->getSourceAlign().valueOrOne(); CopySize = dyn_cast(MCI->getArgOperand(2)); } else if (auto *MCI = dyn_cast(&CI)) { DstAlign = MCI->getDestAlign().valueOrOne(); SrcAlign = MCI->getSourceAlign().valueOrOne(); CopySize = dyn_cast(MCI->getArgOperand(2)); } else if (auto *MMI = dyn_cast(&CI)) { DstAlign = MMI->getDestAlign().valueOrOne(); SrcAlign = MMI->getSourceAlign().valueOrOne(); CopySize = dyn_cast(MMI->getArgOperand(2)); } else { auto *MSI = cast(&CI); DstAlign = MSI->getDestAlign().valueOrOne(); } if (Opcode != TargetOpcode::G_MEMCPY_INLINE) { // We need to propagate the tail call flag from the IR inst as an argument. // Otherwise, we have to pessimize and assume later that we cannot tail call // any memory intrinsics. ICall.addImm(CI.isTailCall() ? 1 : 0); } // Create mem operands to store the alignment and volatile info. MachineMemOperand::Flags LoadFlags = MachineMemOperand::MOLoad; MachineMemOperand::Flags StoreFlags = MachineMemOperand::MOStore; if (IsVol) { LoadFlags |= MachineMemOperand::MOVolatile; StoreFlags |= MachineMemOperand::MOVolatile; } AAMDNodes AAInfo = CI.getAAMetadata(); if (AA && CopySize && AA->pointsToConstantMemory(MemoryLocation( SrcPtr, LocationSize::precise(CopySize->getZExtValue()), AAInfo))) { LoadFlags |= MachineMemOperand::MOInvariant; // FIXME: pointsToConstantMemory probably does not imply dereferenceable, // but the previous usage implied it did. Probably should check // isDereferenceableAndAlignedPointer. LoadFlags |= MachineMemOperand::MODereferenceable; } ICall.addMemOperand( MF->getMachineMemOperand(MachinePointerInfo(CI.getArgOperand(0)), StoreFlags, 1, DstAlign, AAInfo)); if (Opcode != TargetOpcode::G_MEMSET) ICall.addMemOperand(MF->getMachineMemOperand( MachinePointerInfo(SrcPtr), LoadFlags, 1, SrcAlign, AAInfo)); return true; } bool IRTranslator::translateTrap(const CallInst &CI, MachineIRBuilder &MIRBuilder, unsigned Opcode) { StringRef TrapFuncName = CI.getAttributes().getFnAttr("trap-func-name").getValueAsString(); if (TrapFuncName.empty()) { if (Opcode == TargetOpcode::G_UBSANTRAP) { uint64_t Code = cast(CI.getOperand(0))->getZExtValue(); MIRBuilder.buildInstr(Opcode, {}, ArrayRef{Code}); } else { MIRBuilder.buildInstr(Opcode); } return true; } CallLowering::CallLoweringInfo Info; if (Opcode == TargetOpcode::G_UBSANTRAP) Info.OrigArgs.push_back({getOrCreateVRegs(*CI.getArgOperand(0)), CI.getArgOperand(0)->getType(), 0}); Info.Callee = MachineOperand::CreateES(TrapFuncName.data()); Info.CB = &CI; Info.OrigRet = {Register(), Type::getVoidTy(CI.getContext()), 0}; return CLI->lowerCall(MIRBuilder, Info); } bool IRTranslator::translateVectorInterleave2Intrinsic( const CallInst &CI, MachineIRBuilder &MIRBuilder) { assert(CI.getIntrinsicID() == Intrinsic::vector_interleave2 && "This function can only be called on the interleave2 intrinsic!"); // Canonicalize interleave2 to G_SHUFFLE_VECTOR (similar to SelectionDAG). Register Op0 = getOrCreateVReg(*CI.getOperand(0)); Register Op1 = getOrCreateVReg(*CI.getOperand(1)); Register Res = getOrCreateVReg(CI); LLT OpTy = MRI->getType(Op0); MIRBuilder.buildShuffleVector(Res, Op0, Op1, createInterleaveMask(OpTy.getNumElements(), 2)); return true; } bool IRTranslator::translateVectorDeinterleave2Intrinsic( const CallInst &CI, MachineIRBuilder &MIRBuilder) { assert(CI.getIntrinsicID() == Intrinsic::vector_deinterleave2 && "This function can only be called on the deinterleave2 intrinsic!"); // Canonicalize deinterleave2 to shuffles that extract sub-vectors (similar to // SelectionDAG). Register Op = getOrCreateVReg(*CI.getOperand(0)); auto Undef = MIRBuilder.buildUndef(MRI->getType(Op)); ArrayRef Res = getOrCreateVRegs(CI); LLT ResTy = MRI->getType(Res[0]); MIRBuilder.buildShuffleVector(Res[0], Op, Undef, createStrideMask(0, 2, ResTy.getNumElements())); MIRBuilder.buildShuffleVector(Res[1], Op, Undef, createStrideMask(1, 2, ResTy.getNumElements())); return true; } void IRTranslator::getStackGuard(Register DstReg, MachineIRBuilder &MIRBuilder) { const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); MRI->setRegClass(DstReg, TRI->getPointerRegClass(*MF)); auto MIB = MIRBuilder.buildInstr(TargetOpcode::LOAD_STACK_GUARD, {DstReg}, {}); Value *Global = TLI->getSDagStackGuard(*MF->getFunction().getParent()); if (!Global) return; unsigned AddrSpace = Global->getType()->getPointerAddressSpace(); LLT PtrTy = LLT::pointer(AddrSpace, DL->getPointerSizeInBits(AddrSpace)); MachinePointerInfo MPInfo(Global); auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant | MachineMemOperand::MODereferenceable; MachineMemOperand *MemRef = MF->getMachineMemOperand( MPInfo, Flags, PtrTy, DL->getPointerABIAlignment(AddrSpace)); MIB.setMemRefs({MemRef}); } bool IRTranslator::translateOverflowIntrinsic(const CallInst &CI, unsigned Op, MachineIRBuilder &MIRBuilder) { ArrayRef ResRegs = getOrCreateVRegs(CI); MIRBuilder.buildInstr( Op, {ResRegs[0], ResRegs[1]}, {getOrCreateVReg(*CI.getOperand(0)), getOrCreateVReg(*CI.getOperand(1))}); return true; } bool IRTranslator::translateFixedPointIntrinsic(unsigned Op, const CallInst &CI, MachineIRBuilder &MIRBuilder) { Register Dst = getOrCreateVReg(CI); Register Src0 = getOrCreateVReg(*CI.getOperand(0)); Register Src1 = getOrCreateVReg(*CI.getOperand(1)); uint64_t Scale = cast(CI.getOperand(2))->getZExtValue(); MIRBuilder.buildInstr(Op, {Dst}, { Src0, Src1, Scale }); return true; } unsigned IRTranslator::getSimpleIntrinsicOpcode(Intrinsic::ID ID) { switch (ID) { default: break; case Intrinsic::acos: return TargetOpcode::G_FACOS; case Intrinsic::asin: return TargetOpcode::G_FASIN; case Intrinsic::atan: return TargetOpcode::G_FATAN; case Intrinsic::bswap: return TargetOpcode::G_BSWAP; case Intrinsic::bitreverse: return TargetOpcode::G_BITREVERSE; case Intrinsic::fshl: return TargetOpcode::G_FSHL; case Intrinsic::fshr: return TargetOpcode::G_FSHR; case Intrinsic::ceil: return TargetOpcode::G_FCEIL; case Intrinsic::cos: return TargetOpcode::G_FCOS; case Intrinsic::cosh: return TargetOpcode::G_FCOSH; case Intrinsic::ctpop: return TargetOpcode::G_CTPOP; case Intrinsic::exp: return TargetOpcode::G_FEXP; case Intrinsic::exp2: return TargetOpcode::G_FEXP2; case Intrinsic::exp10: return TargetOpcode::G_FEXP10; case Intrinsic::fabs: return TargetOpcode::G_FABS; case Intrinsic::copysign: return TargetOpcode::G_FCOPYSIGN; case Intrinsic::minnum: return TargetOpcode::G_FMINNUM; case Intrinsic::maxnum: return TargetOpcode::G_FMAXNUM; case Intrinsic::minimum: return TargetOpcode::G_FMINIMUM; case Intrinsic::maximum: return TargetOpcode::G_FMAXIMUM; case Intrinsic::canonicalize: return TargetOpcode::G_FCANONICALIZE; case Intrinsic::floor: return TargetOpcode::G_FFLOOR; case Intrinsic::fma: return TargetOpcode::G_FMA; case Intrinsic::log: return TargetOpcode::G_FLOG; case Intrinsic::log2: return TargetOpcode::G_FLOG2; case Intrinsic::log10: return TargetOpcode::G_FLOG10; case Intrinsic::ldexp: return TargetOpcode::G_FLDEXP; case Intrinsic::nearbyint: return TargetOpcode::G_FNEARBYINT; case Intrinsic::pow: return TargetOpcode::G_FPOW; case Intrinsic::powi: return TargetOpcode::G_FPOWI; case Intrinsic::rint: return TargetOpcode::G_FRINT; case Intrinsic::round: return TargetOpcode::G_INTRINSIC_ROUND; case Intrinsic::roundeven: return TargetOpcode::G_INTRINSIC_ROUNDEVEN; case Intrinsic::sin: return TargetOpcode::G_FSIN; case Intrinsic::sinh: return TargetOpcode::G_FSINH; case Intrinsic::sqrt: return TargetOpcode::G_FSQRT; case Intrinsic::tan: return TargetOpcode::G_FTAN; case Intrinsic::tanh: return TargetOpcode::G_FTANH; case Intrinsic::trunc: return TargetOpcode::G_INTRINSIC_TRUNC; case Intrinsic::readcyclecounter: return TargetOpcode::G_READCYCLECOUNTER; case Intrinsic::readsteadycounter: return TargetOpcode::G_READSTEADYCOUNTER; case Intrinsic::ptrmask: return TargetOpcode::G_PTRMASK; case Intrinsic::lrint: return TargetOpcode::G_INTRINSIC_LRINT; case Intrinsic::llrint: return TargetOpcode::G_INTRINSIC_LLRINT; // FADD/FMUL require checking the FMF, so are handled elsewhere. case Intrinsic::vector_reduce_fmin: return TargetOpcode::G_VECREDUCE_FMIN; case Intrinsic::vector_reduce_fmax: return TargetOpcode::G_VECREDUCE_FMAX; case Intrinsic::vector_reduce_fminimum: return TargetOpcode::G_VECREDUCE_FMINIMUM; case Intrinsic::vector_reduce_fmaximum: return TargetOpcode::G_VECREDUCE_FMAXIMUM; case Intrinsic::vector_reduce_add: return TargetOpcode::G_VECREDUCE_ADD; case Intrinsic::vector_reduce_mul: return TargetOpcode::G_VECREDUCE_MUL; case Intrinsic::vector_reduce_and: return TargetOpcode::G_VECREDUCE_AND; case Intrinsic::vector_reduce_or: return TargetOpcode::G_VECREDUCE_OR; case Intrinsic::vector_reduce_xor: return TargetOpcode::G_VECREDUCE_XOR; case Intrinsic::vector_reduce_smax: return TargetOpcode::G_VECREDUCE_SMAX; case Intrinsic::vector_reduce_smin: return TargetOpcode::G_VECREDUCE_SMIN; case Intrinsic::vector_reduce_umax: return TargetOpcode::G_VECREDUCE_UMAX; case Intrinsic::vector_reduce_umin: return TargetOpcode::G_VECREDUCE_UMIN; case Intrinsic::experimental_vector_compress: return TargetOpcode::G_VECTOR_COMPRESS; case Intrinsic::lround: return TargetOpcode::G_LROUND; case Intrinsic::llround: return TargetOpcode::G_LLROUND; case Intrinsic::get_fpenv: return TargetOpcode::G_GET_FPENV; case Intrinsic::get_fpmode: return TargetOpcode::G_GET_FPMODE; } return Intrinsic::not_intrinsic; } bool IRTranslator::translateSimpleIntrinsic(const CallInst &CI, Intrinsic::ID ID, MachineIRBuilder &MIRBuilder) { unsigned Op = getSimpleIntrinsicOpcode(ID); // Is this a simple intrinsic? if (Op == Intrinsic::not_intrinsic) return false; // Yes. Let's translate it. SmallVector VRegs; for (const auto &Arg : CI.args()) VRegs.push_back(getOrCreateVReg(*Arg)); MIRBuilder.buildInstr(Op, {getOrCreateVReg(CI)}, VRegs, MachineInstr::copyFlagsFromInstruction(CI)); return true; } // TODO: Include ConstainedOps.def when all strict instructions are defined. static unsigned getConstrainedOpcode(Intrinsic::ID ID) { switch (ID) { case Intrinsic::experimental_constrained_fadd: return TargetOpcode::G_STRICT_FADD; case Intrinsic::experimental_constrained_fsub: return TargetOpcode::G_STRICT_FSUB; case Intrinsic::experimental_constrained_fmul: return TargetOpcode::G_STRICT_FMUL; case Intrinsic::experimental_constrained_fdiv: return TargetOpcode::G_STRICT_FDIV; case Intrinsic::experimental_constrained_frem: return TargetOpcode::G_STRICT_FREM; case Intrinsic::experimental_constrained_fma: return TargetOpcode::G_STRICT_FMA; case Intrinsic::experimental_constrained_sqrt: return TargetOpcode::G_STRICT_FSQRT; case Intrinsic::experimental_constrained_ldexp: return TargetOpcode::G_STRICT_FLDEXP; default: return 0; } } bool IRTranslator::translateConstrainedFPIntrinsic( const ConstrainedFPIntrinsic &FPI, MachineIRBuilder &MIRBuilder) { fp::ExceptionBehavior EB = *FPI.getExceptionBehavior(); unsigned Opcode = getConstrainedOpcode(FPI.getIntrinsicID()); if (!Opcode) return false; uint32_t Flags = MachineInstr::copyFlagsFromInstruction(FPI); if (EB == fp::ExceptionBehavior::ebIgnore) Flags |= MachineInstr::NoFPExcept; SmallVector VRegs; for (unsigned I = 0, E = FPI.getNonMetadataArgCount(); I != E; ++I) VRegs.push_back(getOrCreateVReg(*FPI.getArgOperand(I))); MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(FPI)}, VRegs, Flags); return true; } std::optional IRTranslator::getArgPhysReg(Argument &Arg) { auto VRegs = getOrCreateVRegs(Arg); if (VRegs.size() != 1) return std::nullopt; // Arguments are lowered as a copy of a livein physical register. auto *VRegDef = MF->getRegInfo().getVRegDef(VRegs[0]); if (!VRegDef || !VRegDef->isCopy()) return std::nullopt; return VRegDef->getOperand(1).getReg().asMCReg(); } bool IRTranslator::translateIfEntryValueArgument(bool isDeclare, Value *Val, const DILocalVariable *Var, const DIExpression *Expr, const DebugLoc &DL, MachineIRBuilder &MIRBuilder) { auto *Arg = dyn_cast(Val); if (!Arg) return false; if (!Expr->isEntryValue()) return false; std::optional PhysReg = getArgPhysReg(*Arg); if (!PhysReg) { LLVM_DEBUG(dbgs() << "Dropping dbg." << (isDeclare ? "declare" : "value") << ": expression is entry_value but " << "couldn't find a physical register\n"); LLVM_DEBUG(dbgs() << *Var << "\n"); return true; } if (isDeclare) { // Append an op deref to account for the fact that this is a dbg_declare. Expr = DIExpression::append(Expr, dwarf::DW_OP_deref); MF->setVariableDbgInfo(Var, Expr, *PhysReg, DL); } else { MIRBuilder.buildDirectDbgValue(*PhysReg, Var, Expr); } return true; } static unsigned getConvOpcode(Intrinsic::ID ID) { switch (ID) { default: llvm_unreachable("Unexpected intrinsic"); case Intrinsic::experimental_convergence_anchor: return TargetOpcode::CONVERGENCECTRL_ANCHOR; case Intrinsic::experimental_convergence_entry: return TargetOpcode::CONVERGENCECTRL_ENTRY; case Intrinsic::experimental_convergence_loop: return TargetOpcode::CONVERGENCECTRL_LOOP; } } bool IRTranslator::translateConvergenceControlIntrinsic( const CallInst &CI, Intrinsic::ID ID, MachineIRBuilder &MIRBuilder) { MachineInstrBuilder MIB = MIRBuilder.buildInstr(getConvOpcode(ID)); Register OutputReg = getOrCreateConvergenceTokenVReg(CI); MIB.addDef(OutputReg); if (ID == Intrinsic::experimental_convergence_loop) { auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl); assert(Bundle && "Expected a convergence control token."); Register InputReg = getOrCreateConvergenceTokenVReg(*Bundle->Inputs[0].get()); MIB.addUse(InputReg); } return true; } bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID, MachineIRBuilder &MIRBuilder) { if (auto *MI = dyn_cast(&CI)) { if (ORE->enabled()) { if (MemoryOpRemark::canHandle(MI, *LibInfo)) { MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo); R.visit(MI); } } } // If this is a simple intrinsic (that is, we just need to add a def of // a vreg, and uses for each arg operand, then translate it. if (translateSimpleIntrinsic(CI, ID, MIRBuilder)) return true; switch (ID) { default: break; case Intrinsic::lifetime_start: case Intrinsic::lifetime_end: { // No stack colouring in O0, discard region information. if (MF->getTarget().getOptLevel() == CodeGenOptLevel::None) return true; unsigned Op = ID == Intrinsic::lifetime_start ? TargetOpcode::LIFETIME_START : TargetOpcode::LIFETIME_END; // Get the underlying objects for the location passed on the lifetime // marker. SmallVector Allocas; getUnderlyingObjects(CI.getArgOperand(1), Allocas); // Iterate over each underlying object, creating lifetime markers for each // static alloca. Quit if we find a non-static alloca. for (const Value *V : Allocas) { const AllocaInst *AI = dyn_cast(V); if (!AI) continue; if (!AI->isStaticAlloca()) return true; MIRBuilder.buildInstr(Op).addFrameIndex(getOrCreateFrameIndex(*AI)); } return true; } case Intrinsic::dbg_declare: { const DbgDeclareInst &DI = cast(CI); assert(DI.getVariable() && "Missing variable"); translateDbgDeclareRecord(DI.getAddress(), DI.hasArgList(), DI.getVariable(), DI.getExpression(), DI.getDebugLoc(), MIRBuilder); return true; } case Intrinsic::dbg_label: { const DbgLabelInst &DI = cast(CI); assert(DI.getLabel() && "Missing label"); assert(DI.getLabel()->isValidLocationForIntrinsic( MIRBuilder.getDebugLoc()) && "Expected inlined-at fields to agree"); MIRBuilder.buildDbgLabel(DI.getLabel()); return true; } case Intrinsic::vaend: // No target I know of cares about va_end. Certainly no in-tree target // does. Simplest intrinsic ever! return true; case Intrinsic::vastart: { Value *Ptr = CI.getArgOperand(0); unsigned ListSize = TLI->getVaListSizeInBits(*DL) / 8; Align Alignment = getKnownAlignment(Ptr, *DL); MIRBuilder.buildInstr(TargetOpcode::G_VASTART, {}, {getOrCreateVReg(*Ptr)}) .addMemOperand(MF->getMachineMemOperand(MachinePointerInfo(Ptr), MachineMemOperand::MOStore, ListSize, Alignment)); return true; } case Intrinsic::dbg_assign: // A dbg.assign is a dbg.value with more information about stack locations, // typically produced during optimisation of variables with leaked // addresses. We can treat it like a normal dbg_value intrinsic here; to // benefit from the full analysis of stack/SSA locations, GlobalISel would // need to register for and use the AssignmentTrackingAnalysis pass. [[fallthrough]]; case Intrinsic::dbg_value: { // This form of DBG_VALUE is target-independent. const DbgValueInst &DI = cast(CI); translateDbgValueRecord(DI.getValue(), DI.hasArgList(), DI.getVariable(), DI.getExpression(), DI.getDebugLoc(), MIRBuilder); return true; } case Intrinsic::uadd_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_UADDO, MIRBuilder); case Intrinsic::sadd_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_SADDO, MIRBuilder); case Intrinsic::usub_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_USUBO, MIRBuilder); case Intrinsic::ssub_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_SSUBO, MIRBuilder); case Intrinsic::umul_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_UMULO, MIRBuilder); case Intrinsic::smul_with_overflow: return translateOverflowIntrinsic(CI, TargetOpcode::G_SMULO, MIRBuilder); case Intrinsic::uadd_sat: return translateBinaryOp(TargetOpcode::G_UADDSAT, CI, MIRBuilder); case Intrinsic::sadd_sat: return translateBinaryOp(TargetOpcode::G_SADDSAT, CI, MIRBuilder); case Intrinsic::usub_sat: return translateBinaryOp(TargetOpcode::G_USUBSAT, CI, MIRBuilder); case Intrinsic::ssub_sat: return translateBinaryOp(TargetOpcode::G_SSUBSAT, CI, MIRBuilder); case Intrinsic::ushl_sat: return translateBinaryOp(TargetOpcode::G_USHLSAT, CI, MIRBuilder); case Intrinsic::sshl_sat: return translateBinaryOp(TargetOpcode::G_SSHLSAT, CI, MIRBuilder); case Intrinsic::umin: return translateBinaryOp(TargetOpcode::G_UMIN, CI, MIRBuilder); case Intrinsic::umax: return translateBinaryOp(TargetOpcode::G_UMAX, CI, MIRBuilder); case Intrinsic::smin: return translateBinaryOp(TargetOpcode::G_SMIN, CI, MIRBuilder); case Intrinsic::smax: return translateBinaryOp(TargetOpcode::G_SMAX, CI, MIRBuilder); case Intrinsic::abs: // TODO: Preserve "int min is poison" arg in GMIR? return translateUnaryOp(TargetOpcode::G_ABS, CI, MIRBuilder); case Intrinsic::smul_fix: return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIX, CI, MIRBuilder); case Intrinsic::umul_fix: return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIX, CI, MIRBuilder); case Intrinsic::smul_fix_sat: return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIXSAT, CI, MIRBuilder); case Intrinsic::umul_fix_sat: return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIXSAT, CI, MIRBuilder); case Intrinsic::sdiv_fix: return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIX, CI, MIRBuilder); case Intrinsic::udiv_fix: return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIX, CI, MIRBuilder); case Intrinsic::sdiv_fix_sat: return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIXSAT, CI, MIRBuilder); case Intrinsic::udiv_fix_sat: return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIXSAT, CI, MIRBuilder); case Intrinsic::fmuladd: { const TargetMachine &TM = MF->getTarget(); Register Dst = getOrCreateVReg(CI); Register Op0 = getOrCreateVReg(*CI.getArgOperand(0)); Register Op1 = getOrCreateVReg(*CI.getArgOperand(1)); Register Op2 = getOrCreateVReg(*CI.getArgOperand(2)); if (TM.Options.AllowFPOpFusion != FPOpFusion::Strict && TLI->isFMAFasterThanFMulAndFAdd(*MF, TLI->getValueType(*DL, CI.getType()))) { // TODO: Revisit this to see if we should move this part of the // lowering to the combiner. MIRBuilder.buildFMA(Dst, Op0, Op1, Op2, MachineInstr::copyFlagsFromInstruction(CI)); } else { LLT Ty = getLLTForType(*CI.getType(), *DL); auto FMul = MIRBuilder.buildFMul( Ty, Op0, Op1, MachineInstr::copyFlagsFromInstruction(CI)); MIRBuilder.buildFAdd(Dst, FMul, Op2, MachineInstr::copyFlagsFromInstruction(CI)); } return true; } case Intrinsic::convert_from_fp16: // FIXME: This intrinsic should probably be removed from the IR. MIRBuilder.buildFPExt(getOrCreateVReg(CI), getOrCreateVReg(*CI.getArgOperand(0)), MachineInstr::copyFlagsFromInstruction(CI)); return true; case Intrinsic::convert_to_fp16: // FIXME: This intrinsic should probably be removed from the IR. MIRBuilder.buildFPTrunc(getOrCreateVReg(CI), getOrCreateVReg(*CI.getArgOperand(0)), MachineInstr::copyFlagsFromInstruction(CI)); return true; case Intrinsic::frexp: { ArrayRef VRegs = getOrCreateVRegs(CI); MIRBuilder.buildFFrexp(VRegs[0], VRegs[1], getOrCreateVReg(*CI.getArgOperand(0)), MachineInstr::copyFlagsFromInstruction(CI)); return true; } case Intrinsic::memcpy_inline: return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY_INLINE); case Intrinsic::memcpy: return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY); case Intrinsic::memmove: return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMMOVE); case Intrinsic::memset: return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMSET); case Intrinsic::eh_typeid_for: { GlobalValue *GV = ExtractTypeInfo(CI.getArgOperand(0)); Register Reg = getOrCreateVReg(CI); unsigned TypeID = MF->getTypeIDFor(GV); MIRBuilder.buildConstant(Reg, TypeID); return true; } case Intrinsic::objectsize: llvm_unreachable("llvm.objectsize.* should have been lowered already"); case Intrinsic::is_constant: llvm_unreachable("llvm.is.constant.* should have been lowered already"); case Intrinsic::stackguard: getStackGuard(getOrCreateVReg(CI), MIRBuilder); return true; case Intrinsic::stackprotector: { LLT PtrTy = getLLTForType(*CI.getArgOperand(0)->getType(), *DL); Register GuardVal; if (TLI->useLoadStackGuardNode()) { GuardVal = MRI->createGenericVirtualRegister(PtrTy); getStackGuard(GuardVal, MIRBuilder); } else GuardVal = getOrCreateVReg(*CI.getArgOperand(0)); // The guard's value. AllocaInst *Slot = cast(CI.getArgOperand(1)); int FI = getOrCreateFrameIndex(*Slot); MF->getFrameInfo().setStackProtectorIndex(FI); MIRBuilder.buildStore( GuardVal, getOrCreateVReg(*Slot), *MF->getMachineMemOperand(MachinePointerInfo::getFixedStack(*MF, FI), MachineMemOperand::MOStore | MachineMemOperand::MOVolatile, PtrTy, Align(8))); return true; } case Intrinsic::stacksave: { MIRBuilder.buildInstr(TargetOpcode::G_STACKSAVE, {getOrCreateVReg(CI)}, {}); return true; } case Intrinsic::stackrestore: { MIRBuilder.buildInstr(TargetOpcode::G_STACKRESTORE, {}, {getOrCreateVReg(*CI.getArgOperand(0))}); return true; } case Intrinsic::cttz: case Intrinsic::ctlz: { ConstantInt *Cst = cast(CI.getArgOperand(1)); bool isTrailing = ID == Intrinsic::cttz; unsigned Opcode = isTrailing ? Cst->isZero() ? TargetOpcode::G_CTTZ : TargetOpcode::G_CTTZ_ZERO_UNDEF : Cst->isZero() ? TargetOpcode::G_CTLZ : TargetOpcode::G_CTLZ_ZERO_UNDEF; MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(CI)}, {getOrCreateVReg(*CI.getArgOperand(0))}); return true; } case Intrinsic::invariant_start: { LLT PtrTy = getLLTForType(*CI.getArgOperand(0)->getType(), *DL); Register Undef = MRI->createGenericVirtualRegister(PtrTy); MIRBuilder.buildUndef(Undef); return true; } case Intrinsic::invariant_end: return true; case Intrinsic::expect: case Intrinsic::annotation: case Intrinsic::ptr_annotation: case Intrinsic::launder_invariant_group: case Intrinsic::strip_invariant_group: { // Drop the intrinsic, but forward the value. MIRBuilder.buildCopy(getOrCreateVReg(CI), getOrCreateVReg(*CI.getArgOperand(0))); return true; } case Intrinsic::assume: case Intrinsic::experimental_noalias_scope_decl: case Intrinsic::var_annotation: case Intrinsic::sideeffect: // Discard annotate attributes, assumptions, and artificial side-effects. return true; case Intrinsic::read_volatile_register: case Intrinsic::read_register: { Value *Arg = CI.getArgOperand(0); MIRBuilder .buildInstr(TargetOpcode::G_READ_REGISTER, {getOrCreateVReg(CI)}, {}) .addMetadata(cast(cast(Arg)->getMetadata())); return true; } case Intrinsic::write_register: { Value *Arg = CI.getArgOperand(0); MIRBuilder.buildInstr(TargetOpcode::G_WRITE_REGISTER) .addMetadata(cast(cast(Arg)->getMetadata())) .addUse(getOrCreateVReg(*CI.getArgOperand(1))); return true; } case Intrinsic::localescape: { MachineBasicBlock &EntryMBB = MF->front(); StringRef EscapedName = GlobalValue::dropLLVMManglingEscape(MF->getName()); // Directly emit some LOCAL_ESCAPE machine instrs. Label assignment emission // is the same on all targets. for (unsigned Idx = 0, E = CI.arg_size(); Idx < E; ++Idx) { Value *Arg = CI.getArgOperand(Idx)->stripPointerCasts(); if (isa(Arg)) continue; // Skip null pointers. They represent a hole in index space. int FI = getOrCreateFrameIndex(*cast(Arg)); MCSymbol *FrameAllocSym = MF->getContext().getOrCreateFrameAllocSymbol(EscapedName, Idx); // This should be inserted at the start of the entry block. auto LocalEscape = MIRBuilder.buildInstrNoInsert(TargetOpcode::LOCAL_ESCAPE) .addSym(FrameAllocSym) .addFrameIndex(FI); EntryMBB.insert(EntryMBB.begin(), LocalEscape); } return true; } case Intrinsic::vector_reduce_fadd: case Intrinsic::vector_reduce_fmul: { // Need to check for the reassoc flag to decide whether we want a // sequential reduction opcode or not. Register Dst = getOrCreateVReg(CI); Register ScalarSrc = getOrCreateVReg(*CI.getArgOperand(0)); Register VecSrc = getOrCreateVReg(*CI.getArgOperand(1)); unsigned Opc = 0; if (!CI.hasAllowReassoc()) { // The sequential ordering case. Opc = ID == Intrinsic::vector_reduce_fadd ? TargetOpcode::G_VECREDUCE_SEQ_FADD : TargetOpcode::G_VECREDUCE_SEQ_FMUL; MIRBuilder.buildInstr(Opc, {Dst}, {ScalarSrc, VecSrc}, MachineInstr::copyFlagsFromInstruction(CI)); return true; } // We split the operation into a separate G_FADD/G_FMUL + the reduce, // since the associativity doesn't matter. unsigned ScalarOpc; if (ID == Intrinsic::vector_reduce_fadd) { Opc = TargetOpcode::G_VECREDUCE_FADD; ScalarOpc = TargetOpcode::G_FADD; } else { Opc = TargetOpcode::G_VECREDUCE_FMUL; ScalarOpc = TargetOpcode::G_FMUL; } LLT DstTy = MRI->getType(Dst); auto Rdx = MIRBuilder.buildInstr( Opc, {DstTy}, {VecSrc}, MachineInstr::copyFlagsFromInstruction(CI)); MIRBuilder.buildInstr(ScalarOpc, {Dst}, {ScalarSrc, Rdx}, MachineInstr::copyFlagsFromInstruction(CI)); return true; } case Intrinsic::trap: return translateTrap(CI, MIRBuilder, TargetOpcode::G_TRAP); case Intrinsic::debugtrap: return translateTrap(CI, MIRBuilder, TargetOpcode::G_DEBUGTRAP); case Intrinsic::ubsantrap: return translateTrap(CI, MIRBuilder, TargetOpcode::G_UBSANTRAP); case Intrinsic::allow_runtime_check: case Intrinsic::allow_ubsan_check: MIRBuilder.buildCopy(getOrCreateVReg(CI), getOrCreateVReg(*ConstantInt::getTrue(CI.getType()))); return true; case Intrinsic::amdgcn_cs_chain: return translateCallBase(CI, MIRBuilder); case Intrinsic::fptrunc_round: { uint32_t Flags = MachineInstr::copyFlagsFromInstruction(CI); // Convert the metadata argument to a constant integer Metadata *MD = cast(CI.getArgOperand(1))->getMetadata(); std::optional RoundMode = convertStrToRoundingMode(cast(MD)->getString()); // Add the Rounding mode as an integer MIRBuilder .buildInstr(TargetOpcode::G_INTRINSIC_FPTRUNC_ROUND, {getOrCreateVReg(CI)}, {getOrCreateVReg(*CI.getArgOperand(0))}, Flags) .addImm((int)*RoundMode); return true; } case Intrinsic::is_fpclass: { Value *FpValue = CI.getOperand(0); ConstantInt *TestMaskValue = cast(CI.getOperand(1)); MIRBuilder .buildInstr(TargetOpcode::G_IS_FPCLASS, {getOrCreateVReg(CI)}, {getOrCreateVReg(*FpValue)}) .addImm(TestMaskValue->getZExtValue()); return true; } case Intrinsic::set_fpenv: { Value *FPEnv = CI.getOperand(0); MIRBuilder.buildSetFPEnv(getOrCreateVReg(*FPEnv)); return true; } case Intrinsic::reset_fpenv: MIRBuilder.buildResetFPEnv(); return true; case Intrinsic::set_fpmode: { Value *FPState = CI.getOperand(0); MIRBuilder.buildSetFPMode(getOrCreateVReg(*FPState)); return true; } case Intrinsic::reset_fpmode: MIRBuilder.buildResetFPMode(); return true; case Intrinsic::vscale: { MIRBuilder.buildVScale(getOrCreateVReg(CI), 1); return true; } case Intrinsic::scmp: MIRBuilder.buildSCmp(getOrCreateVReg(CI), getOrCreateVReg(*CI.getOperand(0)), getOrCreateVReg(*CI.getOperand(1))); return true; case Intrinsic::ucmp: MIRBuilder.buildUCmp(getOrCreateVReg(CI), getOrCreateVReg(*CI.getOperand(0)), getOrCreateVReg(*CI.getOperand(1))); return true; case Intrinsic::prefetch: { Value *Addr = CI.getOperand(0); unsigned RW = cast(CI.getOperand(1))->getZExtValue(); unsigned Locality = cast(CI.getOperand(2))->getZExtValue(); unsigned CacheType = cast(CI.getOperand(3))->getZExtValue(); auto Flags = RW ? MachineMemOperand::MOStore : MachineMemOperand::MOLoad; auto &MMO = *MF->getMachineMemOperand(MachinePointerInfo(Addr), Flags, LLT(), Align()); MIRBuilder.buildPrefetch(getOrCreateVReg(*Addr), RW, Locality, CacheType, MMO); return true; } case Intrinsic::vector_interleave2: case Intrinsic::vector_deinterleave2: { // Both intrinsics have at least one operand. Value *Op0 = CI.getOperand(0); LLT ResTy = getLLTForType(*Op0->getType(), MIRBuilder.getDataLayout()); if (!ResTy.isFixedVector()) return false; if (CI.getIntrinsicID() == Intrinsic::vector_interleave2) return translateVectorInterleave2Intrinsic(CI, MIRBuilder); return translateVectorDeinterleave2Intrinsic(CI, MIRBuilder); } #define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC) \ case Intrinsic::INTRINSIC: #include "llvm/IR/ConstrainedOps.def" return translateConstrainedFPIntrinsic(cast(CI), MIRBuilder); case Intrinsic::experimental_convergence_anchor: case Intrinsic::experimental_convergence_entry: case Intrinsic::experimental_convergence_loop: return translateConvergenceControlIntrinsic(CI, ID, MIRBuilder); } return false; } bool IRTranslator::translateInlineAsm(const CallBase &CB, MachineIRBuilder &MIRBuilder) { const InlineAsmLowering *ALI = MF->getSubtarget().getInlineAsmLowering(); if (!ALI) { LLVM_DEBUG( dbgs() << "Inline asm lowering is not supported for this target yet\n"); return false; } return ALI->lowerInlineAsm( MIRBuilder, CB, [&](const Value &Val) { return getOrCreateVRegs(Val); }); } bool IRTranslator::translateCallBase(const CallBase &CB, MachineIRBuilder &MIRBuilder) { ArrayRef Res = getOrCreateVRegs(CB); SmallVector, 8> Args; Register SwiftInVReg = 0; Register SwiftErrorVReg = 0; for (const auto &Arg : CB.args()) { if (CLI->supportSwiftError() && isSwiftError(Arg)) { assert(SwiftInVReg == 0 && "Expected only one swift error argument"); LLT Ty = getLLTForType(*Arg->getType(), *DL); SwiftInVReg = MRI->createGenericVirtualRegister(Ty); MIRBuilder.buildCopy(SwiftInVReg, SwiftError.getOrCreateVRegUseAt( &CB, &MIRBuilder.getMBB(), Arg)); Args.emplace_back(ArrayRef(SwiftInVReg)); SwiftErrorVReg = SwiftError.getOrCreateVRegDefAt(&CB, &MIRBuilder.getMBB(), Arg); continue; } Args.push_back(getOrCreateVRegs(*Arg)); } if (auto *CI = dyn_cast(&CB)) { if (ORE->enabled()) { if (MemoryOpRemark::canHandle(CI, *LibInfo)) { MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo); R.visit(CI); } } } std::optional PAI; if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_ptrauth)) { // Functions should never be ptrauth-called directly. assert(!CB.getCalledFunction() && "invalid direct ptrauth call"); const Value *Key = Bundle->Inputs[0]; const Value *Discriminator = Bundle->Inputs[1]; // Look through ptrauth constants to try to eliminate the matching bundle // and turn this into a direct call with no ptrauth. // CallLowering will use the raw pointer if it doesn't find the PAI. const auto *CalleeCPA = dyn_cast(CB.getCalledOperand()); if (!CalleeCPA || !isa(CalleeCPA->getPointer()) || !CalleeCPA->isKnownCompatibleWith(Key, Discriminator, *DL)) { // If we can't make it direct, package the bundle into PAI. Register DiscReg = getOrCreateVReg(*Discriminator); PAI = CallLowering::PtrAuthInfo{cast(Key)->getZExtValue(), DiscReg}; } } Register ConvergenceCtrlToken = 0; if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_convergencectrl)) { const auto &Token = *Bundle->Inputs[0].get(); ConvergenceCtrlToken = getOrCreateConvergenceTokenVReg(Token); } // We don't set HasCalls on MFI here yet because call lowering may decide to // optimize into tail calls. Instead, we defer that to selection where a final // scan is done to check if any instructions are calls. bool Success = CLI->lowerCall( MIRBuilder, CB, Res, Args, SwiftErrorVReg, PAI, ConvergenceCtrlToken, [&]() { return getOrCreateVReg(*CB.getCalledOperand()); }); // Check if we just inserted a tail call. if (Success) { assert(!HasTailCall && "Can't tail call return twice from block?"); const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo(); HasTailCall = TII->isTailCall(*std::prev(MIRBuilder.getInsertPt())); } return Success; } bool IRTranslator::translateCall(const User &U, MachineIRBuilder &MIRBuilder) { const CallInst &CI = cast(U); auto TII = MF->getTarget().getIntrinsicInfo(); const Function *F = CI.getCalledFunction(); // FIXME: support Windows dllimport function calls and calls through // weak symbols. if (F && (F->hasDLLImportStorageClass() || (MF->getTarget().getTargetTriple().isOSWindows() && F->hasExternalWeakLinkage()))) return false; // FIXME: support control flow guard targets. if (CI.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget)) return false; // FIXME: support statepoints and related. if (isa(U)) return false; if (CI.isInlineAsm()) return translateInlineAsm(CI, MIRBuilder); diagnoseDontCall(CI); Intrinsic::ID ID = Intrinsic::not_intrinsic; if (F && F->isIntrinsic()) { ID = F->getIntrinsicID(); if (TII && ID == Intrinsic::not_intrinsic) ID = static_cast(TII->getIntrinsicID(F)); } if (!F || !F->isIntrinsic() || ID == Intrinsic::not_intrinsic) return translateCallBase(CI, MIRBuilder); assert(ID != Intrinsic::not_intrinsic && "unknown intrinsic"); if (translateKnownIntrinsic(CI, ID, MIRBuilder)) return true; ArrayRef ResultRegs; if (!CI.getType()->isVoidTy()) ResultRegs = getOrCreateVRegs(CI); // Ignore the callsite attributes. Backend code is most likely not expecting // an intrinsic to sometimes have side effects and sometimes not. MachineInstrBuilder MIB = MIRBuilder.buildIntrinsic(ID, ResultRegs); if (isa(CI)) MIB->copyIRFlags(CI); for (const auto &Arg : enumerate(CI.args())) { // If this is required to be an immediate, don't materialize it in a // register. if (CI.paramHasAttr(Arg.index(), Attribute::ImmArg)) { if (ConstantInt *CI = dyn_cast(Arg.value())) { // imm arguments are more convenient than cimm (and realistically // probably sufficient), so use them. assert(CI->getBitWidth() <= 64 && "large intrinsic immediates not handled"); MIB.addImm(CI->getSExtValue()); } else { MIB.addFPImm(cast(Arg.value())); } } else if (auto *MDVal = dyn_cast(Arg.value())) { auto *MD = MDVal->getMetadata(); auto *MDN = dyn_cast(MD); if (!MDN) { if (auto *ConstMD = dyn_cast(MD)) MDN = MDNode::get(MF->getFunction().getContext(), ConstMD); else // This was probably an MDString. return false; } MIB.addMetadata(MDN); } else { ArrayRef VRegs = getOrCreateVRegs(*Arg.value()); if (VRegs.size() > 1) return false; MIB.addUse(VRegs[0]); } } // Add a MachineMemOperand if it is a target mem intrinsic. TargetLowering::IntrinsicInfo Info; // TODO: Add a GlobalISel version of getTgtMemIntrinsic. if (TLI->getTgtMemIntrinsic(Info, CI, *MF, ID)) { Align Alignment = Info.align.value_or( DL->getABITypeAlign(Info.memVT.getTypeForEVT(F->getContext()))); LLT MemTy = Info.memVT.isSimple() ? getLLTForMVT(Info.memVT.getSimpleVT()) : LLT::scalar(Info.memVT.getStoreSizeInBits()); // TODO: We currently just fallback to address space 0 if getTgtMemIntrinsic // didn't yield anything useful. MachinePointerInfo MPI; if (Info.ptrVal) MPI = MachinePointerInfo(Info.ptrVal, Info.offset); else if (Info.fallbackAddressSpace) MPI = MachinePointerInfo(*Info.fallbackAddressSpace); MIB.addMemOperand( MF->getMachineMemOperand(MPI, Info.flags, MemTy, Alignment, CI.getAAMetadata())); } if (CI.isConvergent()) { if (auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl)) { auto *Token = Bundle->Inputs[0].get(); Register TokenReg = getOrCreateVReg(*Token); MIB.addUse(TokenReg, RegState::Implicit); } } return true; } bool IRTranslator::findUnwindDestinations( const BasicBlock *EHPadBB, BranchProbability Prob, SmallVectorImpl> &UnwindDests) { EHPersonality Personality = classifyEHPersonality( EHPadBB->getParent()->getFunction().getPersonalityFn()); bool IsMSVCCXX = Personality == EHPersonality::MSVC_CXX; bool IsCoreCLR = Personality == EHPersonality::CoreCLR; bool IsWasmCXX = Personality == EHPersonality::Wasm_CXX; bool IsSEH = isAsynchronousEHPersonality(Personality); if (IsWasmCXX) { // Ignore this for now. return false; } while (EHPadBB) { const Instruction *Pad = EHPadBB->getFirstNonPHI(); BasicBlock *NewEHPadBB = nullptr; if (isa(Pad)) { // Stop on landingpads. They are not funclets. UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob); break; } if (isa(Pad)) { // Stop on cleanup pads. Cleanups are always funclet entries for all known // personalities. UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob); UnwindDests.back().first->setIsEHScopeEntry(); UnwindDests.back().first->setIsEHFuncletEntry(); break; } if (auto *CatchSwitch = dyn_cast(Pad)) { // Add the catchpad handlers to the possible destinations. for (const BasicBlock *CatchPadBB : CatchSwitch->handlers()) { UnwindDests.emplace_back(&getMBB(*CatchPadBB), Prob); // For MSVC++ and the CLR, catchblocks are funclets and need prologues. if (IsMSVCCXX || IsCoreCLR) UnwindDests.back().first->setIsEHFuncletEntry(); if (!IsSEH) UnwindDests.back().first->setIsEHScopeEntry(); } NewEHPadBB = CatchSwitch->getUnwindDest(); } else { continue; } BranchProbabilityInfo *BPI = FuncInfo.BPI; if (BPI && NewEHPadBB) Prob *= BPI->getEdgeProbability(EHPadBB, NewEHPadBB); EHPadBB = NewEHPadBB; } return true; } bool IRTranslator::translateInvoke(const User &U, MachineIRBuilder &MIRBuilder) { const InvokeInst &I = cast(U); MCContext &Context = MF->getContext(); const BasicBlock *ReturnBB = I.getSuccessor(0); const BasicBlock *EHPadBB = I.getSuccessor(1); const Function *Fn = I.getCalledFunction(); // FIXME: support invoking patchpoint and statepoint intrinsics. if (Fn && Fn->isIntrinsic()) return false; // FIXME: support whatever these are. if (I.hasDeoptState()) return false; // FIXME: support control flow guard targets. if (I.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget)) return false; // FIXME: support Windows exception handling. if (!isa(EHPadBB->getFirstNonPHI())) return false; // FIXME: support Windows dllimport function calls and calls through // weak symbols. if (Fn && (Fn->hasDLLImportStorageClass() || (MF->getTarget().getTargetTriple().isOSWindows() && Fn->hasExternalWeakLinkage()))) return false; bool LowerInlineAsm = I.isInlineAsm(); bool NeedEHLabel = true; // Emit the actual call, bracketed by EH_LABELs so that the MF knows about // the region covered by the try. MCSymbol *BeginSymbol = nullptr; if (NeedEHLabel) { MIRBuilder.buildInstr(TargetOpcode::G_INVOKE_REGION_START); BeginSymbol = Context.createTempSymbol(); MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(BeginSymbol); } if (LowerInlineAsm) { if (!translateInlineAsm(I, MIRBuilder)) return false; } else if (!translateCallBase(I, MIRBuilder)) return false; MCSymbol *EndSymbol = nullptr; if (NeedEHLabel) { EndSymbol = Context.createTempSymbol(); MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(EndSymbol); } SmallVector, 1> UnwindDests; BranchProbabilityInfo *BPI = FuncInfo.BPI; MachineBasicBlock *InvokeMBB = &MIRBuilder.getMBB(); BranchProbability EHPadBBProb = BPI ? BPI->getEdgeProbability(InvokeMBB->getBasicBlock(), EHPadBB) : BranchProbability::getZero(); if (!findUnwindDestinations(EHPadBB, EHPadBBProb, UnwindDests)) return false; MachineBasicBlock &EHPadMBB = getMBB(*EHPadBB), &ReturnMBB = getMBB(*ReturnBB); // Update successor info. addSuccessorWithProb(InvokeMBB, &ReturnMBB); for (auto &UnwindDest : UnwindDests) { UnwindDest.first->setIsEHPad(); addSuccessorWithProb(InvokeMBB, UnwindDest.first, UnwindDest.second); } InvokeMBB->normalizeSuccProbs(); if (NeedEHLabel) { assert(BeginSymbol && "Expected a begin symbol!"); assert(EndSymbol && "Expected an end symbol!"); MF->addInvoke(&EHPadMBB, BeginSymbol, EndSymbol); } MIRBuilder.buildBr(ReturnMBB); return true; } bool IRTranslator::translateCallBr(const User &U, MachineIRBuilder &MIRBuilder) { // FIXME: Implement this. return false; } bool IRTranslator::translateLandingPad(const User &U, MachineIRBuilder &MIRBuilder) { const LandingPadInst &LP = cast(U); MachineBasicBlock &MBB = MIRBuilder.getMBB(); MBB.setIsEHPad(); // If there aren't registers to copy the values into (e.g., during SjLj // exceptions), then don't bother. const Constant *PersonalityFn = MF->getFunction().getPersonalityFn(); if (TLI->getExceptionPointerRegister(PersonalityFn) == 0 && TLI->getExceptionSelectorRegister(PersonalityFn) == 0) return true; // If landingpad's return type is token type, we don't create DAG nodes // for its exception pointer and selector value. The extraction of exception // pointer or selector value from token type landingpads is not currently // supported. if (LP.getType()->isTokenTy()) return true; // Add a label to mark the beginning of the landing pad. Deletion of the // landing pad can thus be detected via the MachineModuleInfo. MIRBuilder.buildInstr(TargetOpcode::EH_LABEL) .addSym(MF->addLandingPad(&MBB)); // If the unwinder does not preserve all registers, ensure that the // function marks the clobbered registers as used. const TargetRegisterInfo &TRI = *MF->getSubtarget().getRegisterInfo(); if (auto *RegMask = TRI.getCustomEHPadPreservedMask(*MF)) MF->getRegInfo().addPhysRegsUsedFromRegMask(RegMask); LLT Ty = getLLTForType(*LP.getType(), *DL); Register Undef = MRI->createGenericVirtualRegister(Ty); MIRBuilder.buildUndef(Undef); SmallVector Tys; for (Type *Ty : cast(LP.getType())->elements()) Tys.push_back(getLLTForType(*Ty, *DL)); assert(Tys.size() == 2 && "Only two-valued landingpads are supported"); // Mark exception register as live in. Register ExceptionReg = TLI->getExceptionPointerRegister(PersonalityFn); if (!ExceptionReg) return false; MBB.addLiveIn(ExceptionReg); ArrayRef ResRegs = getOrCreateVRegs(LP); MIRBuilder.buildCopy(ResRegs[0], ExceptionReg); Register SelectorReg = TLI->getExceptionSelectorRegister(PersonalityFn); if (!SelectorReg) return false; MBB.addLiveIn(SelectorReg); Register PtrVReg = MRI->createGenericVirtualRegister(Tys[0]); MIRBuilder.buildCopy(PtrVReg, SelectorReg); MIRBuilder.buildCast(ResRegs[1], PtrVReg); return true; } bool IRTranslator::translateAlloca(const User &U, MachineIRBuilder &MIRBuilder) { auto &AI = cast(U); if (AI.isSwiftError()) return true; if (AI.isStaticAlloca()) { Register Res = getOrCreateVReg(AI); int FI = getOrCreateFrameIndex(AI); MIRBuilder.buildFrameIndex(Res, FI); return true; } // FIXME: support stack probing for Windows. if (MF->getTarget().getTargetTriple().isOSWindows()) return false; // Now we're in the harder dynamic case. Register NumElts = getOrCreateVReg(*AI.getArraySize()); Type *IntPtrIRTy = DL->getIntPtrType(AI.getType()); LLT IntPtrTy = getLLTForType(*IntPtrIRTy, *DL); if (MRI->getType(NumElts) != IntPtrTy) { Register ExtElts = MRI->createGenericVirtualRegister(IntPtrTy); MIRBuilder.buildZExtOrTrunc(ExtElts, NumElts); NumElts = ExtElts; } Type *Ty = AI.getAllocatedType(); Register AllocSize = MRI->createGenericVirtualRegister(IntPtrTy); Register TySize = getOrCreateVReg(*ConstantInt::get(IntPtrIRTy, DL->getTypeAllocSize(Ty))); MIRBuilder.buildMul(AllocSize, NumElts, TySize); // Round the size of the allocation up to the stack alignment size // by add SA-1 to the size. This doesn't overflow because we're computing // an address inside an alloca. Align StackAlign = MF->getSubtarget().getFrameLowering()->getStackAlign(); auto SAMinusOne = MIRBuilder.buildConstant(IntPtrTy, StackAlign.value() - 1); auto AllocAdd = MIRBuilder.buildAdd(IntPtrTy, AllocSize, SAMinusOne, MachineInstr::NoUWrap); auto AlignCst = MIRBuilder.buildConstant(IntPtrTy, ~(uint64_t)(StackAlign.value() - 1)); auto AlignedAlloc = MIRBuilder.buildAnd(IntPtrTy, AllocAdd, AlignCst); Align Alignment = std::max(AI.getAlign(), DL->getPrefTypeAlign(Ty)); if (Alignment <= StackAlign) Alignment = Align(1); MIRBuilder.buildDynStackAlloc(getOrCreateVReg(AI), AlignedAlloc, Alignment); MF->getFrameInfo().CreateVariableSizedObject(Alignment, &AI); assert(MF->getFrameInfo().hasVarSizedObjects()); return true; } bool IRTranslator::translateVAArg(const User &U, MachineIRBuilder &MIRBuilder) { // FIXME: We may need more info about the type. Because of how LLT works, // we're completely discarding the i64/double distinction here (amongst // others). Fortunately the ABIs I know of where that matters don't use va_arg // anyway but that's not guaranteed. MIRBuilder.buildInstr(TargetOpcode::G_VAARG, {getOrCreateVReg(U)}, {getOrCreateVReg(*U.getOperand(0)), DL->getABITypeAlign(U.getType()).value()}); return true; } bool IRTranslator::translateUnreachable(const User &U, MachineIRBuilder &MIRBuilder) { if (!MF->getTarget().Options.TrapUnreachable) return true; auto &UI = cast(U); // We may be able to ignore unreachable behind a noreturn call. if (const CallInst *Call = dyn_cast_or_null(UI.getPrevNode()); Call && Call->doesNotReturn()) { if (MF->getTarget().Options.NoTrapAfterNoreturn) return true; // Do not emit an additional trap instruction. if (Call->isNonContinuableTrap()) return true; } MIRBuilder.buildTrap(); return true; } bool IRTranslator::translateInsertElement(const User &U, MachineIRBuilder &MIRBuilder) { // If it is a <1 x Ty> vector, use the scalar as it is // not a legal vector type in LLT. if (auto *FVT = dyn_cast(U.getType()); FVT && FVT->getNumElements() == 1) return translateCopy(U, *U.getOperand(1), MIRBuilder); Register Res = getOrCreateVReg(U); Register Val = getOrCreateVReg(*U.getOperand(0)); Register Elt = getOrCreateVReg(*U.getOperand(1)); unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits(); Register Idx; if (auto *CI = dyn_cast(U.getOperand(2))) { if (CI->getBitWidth() != PreferredVecIdxWidth) { APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth); auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx); Idx = getOrCreateVReg(*NewIdxCI); } } if (!Idx) Idx = getOrCreateVReg(*U.getOperand(2)); if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) { const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth); Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0); } MIRBuilder.buildInsertVectorElement(Res, Val, Elt, Idx); return true; } bool IRTranslator::translateExtractElement(const User &U, MachineIRBuilder &MIRBuilder) { // If it is a <1 x Ty> vector, use the scalar as it is // not a legal vector type in LLT. if (cast(U.getOperand(0)->getType())->getNumElements() == 1) return translateCopy(U, *U.getOperand(0), MIRBuilder); Register Res = getOrCreateVReg(U); Register Val = getOrCreateVReg(*U.getOperand(0)); unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits(); Register Idx; if (auto *CI = dyn_cast(U.getOperand(1))) { if (CI->getBitWidth() != PreferredVecIdxWidth) { APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth); auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx); Idx = getOrCreateVReg(*NewIdxCI); } } if (!Idx) Idx = getOrCreateVReg(*U.getOperand(1)); if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) { const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth); Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0); } MIRBuilder.buildExtractVectorElement(Res, Val, Idx); return true; } bool IRTranslator::translateShuffleVector(const User &U, MachineIRBuilder &MIRBuilder) { // A ShuffleVector that has operates on scalable vectors is a splat vector // where the value of the splat vector is the 0th element of the first // operand, since the index mask operand is the zeroinitializer (undef and // poison are treated as zeroinitializer here). if (U.getOperand(0)->getType()->isScalableTy()) { Value *Op0 = U.getOperand(0); auto SplatVal = MIRBuilder.buildExtractVectorElementConstant( LLT::scalar(Op0->getType()->getScalarSizeInBits()), getOrCreateVReg(*Op0), 0); MIRBuilder.buildSplatVector(getOrCreateVReg(U), SplatVal); return true; } ArrayRef Mask; if (auto *SVI = dyn_cast(&U)) Mask = SVI->getShuffleMask(); else Mask = cast(U).getShuffleMask(); ArrayRef MaskAlloc = MF->allocateShuffleMask(Mask); MIRBuilder .buildInstr(TargetOpcode::G_SHUFFLE_VECTOR, {getOrCreateVReg(U)}, {getOrCreateVReg(*U.getOperand(0)), getOrCreateVReg(*U.getOperand(1))}) .addShuffleMask(MaskAlloc); return true; } bool IRTranslator::translatePHI(const User &U, MachineIRBuilder &MIRBuilder) { const PHINode &PI = cast(U); SmallVector Insts; for (auto Reg : getOrCreateVRegs(PI)) { auto MIB = MIRBuilder.buildInstr(TargetOpcode::G_PHI, {Reg}, {}); Insts.push_back(MIB.getInstr()); } PendingPHIs.emplace_back(&PI, std::move(Insts)); return true; } bool IRTranslator::translateAtomicCmpXchg(const User &U, MachineIRBuilder &MIRBuilder) { const AtomicCmpXchgInst &I = cast(U); auto Flags = TLI->getAtomicMemOperandFlags(I, *DL); auto Res = getOrCreateVRegs(I); Register OldValRes = Res[0]; Register SuccessRes = Res[1]; Register Addr = getOrCreateVReg(*I.getPointerOperand()); Register Cmp = getOrCreateVReg(*I.getCompareOperand()); Register NewVal = getOrCreateVReg(*I.getNewValOperand()); MIRBuilder.buildAtomicCmpXchgWithSuccess( OldValRes, SuccessRes, Addr, Cmp, NewVal, *MF->getMachineMemOperand( MachinePointerInfo(I.getPointerOperand()), Flags, MRI->getType(Cmp), getMemOpAlign(I), I.getAAMetadata(), nullptr, I.getSyncScopeID(), I.getSuccessOrdering(), I.getFailureOrdering())); return true; } bool IRTranslator::translateAtomicRMW(const User &U, MachineIRBuilder &MIRBuilder) { const AtomicRMWInst &I = cast(U); auto Flags = TLI->getAtomicMemOperandFlags(I, *DL); Register Res = getOrCreateVReg(I); Register Addr = getOrCreateVReg(*I.getPointerOperand()); Register Val = getOrCreateVReg(*I.getValOperand()); unsigned Opcode = 0; switch (I.getOperation()) { default: return false; case AtomicRMWInst::Xchg: Opcode = TargetOpcode::G_ATOMICRMW_XCHG; break; case AtomicRMWInst::Add: Opcode = TargetOpcode::G_ATOMICRMW_ADD; break; case AtomicRMWInst::Sub: Opcode = TargetOpcode::G_ATOMICRMW_SUB; break; case AtomicRMWInst::And: Opcode = TargetOpcode::G_ATOMICRMW_AND; break; case AtomicRMWInst::Nand: Opcode = TargetOpcode::G_ATOMICRMW_NAND; break; case AtomicRMWInst::Or: Opcode = TargetOpcode::G_ATOMICRMW_OR; break; case AtomicRMWInst::Xor: Opcode = TargetOpcode::G_ATOMICRMW_XOR; break; case AtomicRMWInst::Max: Opcode = TargetOpcode::G_ATOMICRMW_MAX; break; case AtomicRMWInst::Min: Opcode = TargetOpcode::G_ATOMICRMW_MIN; break; case AtomicRMWInst::UMax: Opcode = TargetOpcode::G_ATOMICRMW_UMAX; break; case AtomicRMWInst::UMin: Opcode = TargetOpcode::G_ATOMICRMW_UMIN; break; case AtomicRMWInst::FAdd: Opcode = TargetOpcode::G_ATOMICRMW_FADD; break; case AtomicRMWInst::FSub: Opcode = TargetOpcode::G_ATOMICRMW_FSUB; break; case AtomicRMWInst::FMax: Opcode = TargetOpcode::G_ATOMICRMW_FMAX; break; case AtomicRMWInst::FMin: Opcode = TargetOpcode::G_ATOMICRMW_FMIN; break; case AtomicRMWInst::UIncWrap: Opcode = TargetOpcode::G_ATOMICRMW_UINC_WRAP; break; case AtomicRMWInst::UDecWrap: Opcode = TargetOpcode::G_ATOMICRMW_UDEC_WRAP; break; } MIRBuilder.buildAtomicRMW( Opcode, Res, Addr, Val, *MF->getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()), Flags, MRI->getType(Val), getMemOpAlign(I), I.getAAMetadata(), nullptr, I.getSyncScopeID(), I.getOrdering())); return true; } bool IRTranslator::translateFence(const User &U, MachineIRBuilder &MIRBuilder) { const FenceInst &Fence = cast(U); MIRBuilder.buildFence(static_cast(Fence.getOrdering()), Fence.getSyncScopeID()); return true; } bool IRTranslator::translateFreeze(const User &U, MachineIRBuilder &MIRBuilder) { const ArrayRef DstRegs = getOrCreateVRegs(U); const ArrayRef SrcRegs = getOrCreateVRegs(*U.getOperand(0)); assert(DstRegs.size() == SrcRegs.size() && "Freeze with different source and destination type?"); for (unsigned I = 0; I < DstRegs.size(); ++I) { MIRBuilder.buildFreeze(DstRegs[I], SrcRegs[I]); } return true; } void IRTranslator::finishPendingPhis() { #ifndef NDEBUG DILocationVerifier Verifier; GISelObserverWrapper WrapperObserver(&Verifier); RAIIDelegateInstaller DelInstall(*MF, &WrapperObserver); #endif // ifndef NDEBUG for (auto &Phi : PendingPHIs) { const PHINode *PI = Phi.first; if (PI->getType()->isEmptyTy()) continue; ArrayRef ComponentPHIs = Phi.second; MachineBasicBlock *PhiMBB = ComponentPHIs[0]->getParent(); EntryBuilder->setDebugLoc(PI->getDebugLoc()); #ifndef NDEBUG Verifier.setCurrentInst(PI); #endif // ifndef NDEBUG SmallSet SeenPreds; for (unsigned i = 0; i < PI->getNumIncomingValues(); ++i) { auto IRPred = PI->getIncomingBlock(i); ArrayRef ValRegs = getOrCreateVRegs(*PI->getIncomingValue(i)); for (auto *Pred : getMachinePredBBs({IRPred, PI->getParent()})) { if (SeenPreds.count(Pred) || !PhiMBB->isPredecessor(Pred)) continue; SeenPreds.insert(Pred); for (unsigned j = 0; j < ValRegs.size(); ++j) { MachineInstrBuilder MIB(*MF, ComponentPHIs[j]); MIB.addUse(ValRegs[j]); MIB.addMBB(Pred); } } } } } void IRTranslator::translateDbgValueRecord(Value *V, bool HasArgList, const DILocalVariable *Variable, const DIExpression *Expression, const DebugLoc &DL, MachineIRBuilder &MIRBuilder) { assert(Variable->isValidLocationForIntrinsic(DL) && "Expected inlined-at fields to agree"); // Act as if we're handling a debug intrinsic. MIRBuilder.setDebugLoc(DL); if (!V || HasArgList) { // DI cannot produce a valid DBG_VALUE, so produce an undef DBG_VALUE to // terminate any prior location. MIRBuilder.buildIndirectDbgValue(0, Variable, Expression); return; } if (const auto *CI = dyn_cast(V)) { MIRBuilder.buildConstDbgValue(*CI, Variable, Expression); return; } if (auto *AI = dyn_cast(V); AI && AI->isStaticAlloca() && Expression->startsWithDeref()) { // If the value is an alloca and the expression starts with a // dereference, track a stack slot instead of a register, as registers // may be clobbered. auto ExprOperands = Expression->getElements(); auto *ExprDerefRemoved = DIExpression::get(AI->getContext(), ExprOperands.drop_front()); MIRBuilder.buildFIDbgValue(getOrCreateFrameIndex(*AI), Variable, ExprDerefRemoved); return; } if (translateIfEntryValueArgument(false, V, Variable, Expression, DL, MIRBuilder)) return; for (Register Reg : getOrCreateVRegs(*V)) { // FIXME: This does not handle register-indirect values at offset 0. The // direct/indirect thing shouldn't really be handled by something as // implicit as reg+noreg vs reg+imm in the first place, but it seems // pretty baked in right now. MIRBuilder.buildDirectDbgValue(Reg, Variable, Expression); } return; } void IRTranslator::translateDbgDeclareRecord(Value *Address, bool HasArgList, const DILocalVariable *Variable, const DIExpression *Expression, const DebugLoc &DL, MachineIRBuilder &MIRBuilder) { if (!Address || isa(Address)) { LLVM_DEBUG(dbgs() << "Dropping debug info for " << *Variable << "\n"); return; } assert(Variable->isValidLocationForIntrinsic(DL) && "Expected inlined-at fields to agree"); auto AI = dyn_cast(Address); if (AI && AI->isStaticAlloca()) { // Static allocas are tracked at the MF level, no need for DBG_VALUE // instructions (in fact, they get ignored if they *do* exist). MF->setVariableDbgInfo(Variable, Expression, getOrCreateFrameIndex(*AI), DL); return; } if (translateIfEntryValueArgument(true, Address, Variable, Expression, DL, MIRBuilder)) return; // A dbg.declare describes the address of a source variable, so lower it // into an indirect DBG_VALUE. MIRBuilder.setDebugLoc(DL); MIRBuilder.buildIndirectDbgValue(getOrCreateVReg(*Address), Variable, Expression); return; } void IRTranslator::translateDbgInfo(const Instruction &Inst, MachineIRBuilder &MIRBuilder) { for (DbgRecord &DR : Inst.getDbgRecordRange()) { if (DbgLabelRecord *DLR = dyn_cast(&DR)) { MIRBuilder.setDebugLoc(DLR->getDebugLoc()); assert(DLR->getLabel() && "Missing label"); assert(DLR->getLabel()->isValidLocationForIntrinsic( MIRBuilder.getDebugLoc()) && "Expected inlined-at fields to agree"); MIRBuilder.buildDbgLabel(DLR->getLabel()); continue; } DbgVariableRecord &DVR = cast(DR); const DILocalVariable *Variable = DVR.getVariable(); const DIExpression *Expression = DVR.getExpression(); Value *V = DVR.getVariableLocationOp(0); if (DVR.isDbgDeclare()) translateDbgDeclareRecord(V, DVR.hasArgList(), Variable, Expression, DVR.getDebugLoc(), MIRBuilder); else translateDbgValueRecord(V, DVR.hasArgList(), Variable, Expression, DVR.getDebugLoc(), MIRBuilder); } } bool IRTranslator::translate(const Instruction &Inst) { CurBuilder->setDebugLoc(Inst.getDebugLoc()); CurBuilder->setPCSections(Inst.getMetadata(LLVMContext::MD_pcsections)); CurBuilder->setMMRAMetadata(Inst.getMetadata(LLVMContext::MD_mmra)); if (TLI->fallBackToDAGISel(Inst)) return false; switch (Inst.getOpcode()) { #define HANDLE_INST(NUM, OPCODE, CLASS) \ case Instruction::OPCODE: \ return translate##OPCODE(Inst, *CurBuilder.get()); #include "llvm/IR/Instruction.def" default: return false; } } bool IRTranslator::translate(const Constant &C, Register Reg) { // We only emit constants into the entry block from here. To prevent jumpy // debug behaviour remove debug line. if (auto CurrInstDL = CurBuilder->getDL()) EntryBuilder->setDebugLoc(DebugLoc()); if (auto CI = dyn_cast(&C)) EntryBuilder->buildConstant(Reg, *CI); else if (auto CF = dyn_cast(&C)) EntryBuilder->buildFConstant(Reg, *CF); else if (isa(C)) EntryBuilder->buildUndef(Reg); else if (isa(C)) EntryBuilder->buildConstant(Reg, 0); else if (auto GV = dyn_cast(&C)) EntryBuilder->buildGlobalValue(Reg, GV); else if (auto CPA = dyn_cast(&C)) { Register Addr = getOrCreateVReg(*CPA->getPointer()); Register AddrDisc = getOrCreateVReg(*CPA->getAddrDiscriminator()); EntryBuilder->buildConstantPtrAuth(Reg, CPA, Addr, AddrDisc); } else if (auto CAZ = dyn_cast(&C)) { if (!isa(CAZ->getType())) return false; // Return the scalar if it is a <1 x Ty> vector. unsigned NumElts = CAZ->getElementCount().getFixedValue(); if (NumElts == 1) return translateCopy(C, *CAZ->getElementValue(0u), *EntryBuilder); SmallVector Ops; for (unsigned I = 0; I < NumElts; ++I) { Constant &Elt = *CAZ->getElementValue(I); Ops.push_back(getOrCreateVReg(Elt)); } EntryBuilder->buildBuildVector(Reg, Ops); } else if (auto CV = dyn_cast(&C)) { // Return the scalar if it is a <1 x Ty> vector. if (CV->getNumElements() == 1) return translateCopy(C, *CV->getElementAsConstant(0), *EntryBuilder); SmallVector Ops; for (unsigned i = 0; i < CV->getNumElements(); ++i) { Constant &Elt = *CV->getElementAsConstant(i); Ops.push_back(getOrCreateVReg(Elt)); } EntryBuilder->buildBuildVector(Reg, Ops); } else if (auto CE = dyn_cast(&C)) { switch(CE->getOpcode()) { #define HANDLE_INST(NUM, OPCODE, CLASS) \ case Instruction::OPCODE: \ return translate##OPCODE(*CE, *EntryBuilder.get()); #include "llvm/IR/Instruction.def" default: return false; } } else if (auto CV = dyn_cast(&C)) { if (CV->getNumOperands() == 1) return translateCopy(C, *CV->getOperand(0), *EntryBuilder); SmallVector Ops; for (unsigned i = 0; i < CV->getNumOperands(); ++i) { Ops.push_back(getOrCreateVReg(*CV->getOperand(i))); } EntryBuilder->buildBuildVector(Reg, Ops); } else if (auto *BA = dyn_cast(&C)) { EntryBuilder->buildBlockAddress(Reg, BA); } else return false; return true; } bool IRTranslator::finalizeBasicBlock(const BasicBlock &BB, MachineBasicBlock &MBB) { for (auto &BTB : SL->BitTestCases) { // Emit header first, if it wasn't already emitted. if (!BTB.Emitted) emitBitTestHeader(BTB, BTB.Parent); BranchProbability UnhandledProb = BTB.Prob; for (unsigned j = 0, ej = BTB.Cases.size(); j != ej; ++j) { UnhandledProb -= BTB.Cases[j].ExtraProb; // Set the current basic block to the mbb we wish to insert the code into MachineBasicBlock *MBB = BTB.Cases[j].ThisBB; // If all cases cover a contiguous range, it is not necessary to jump to // the default block after the last bit test fails. This is because the // range check during bit test header creation has guaranteed that every // case here doesn't go outside the range. In this case, there is no need // to perform the last bit test, as it will always be true. Instead, make // the second-to-last bit-test fall through to the target of the last bit // test, and delete the last bit test. MachineBasicBlock *NextMBB; if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) { // Second-to-last bit-test with contiguous range: fall through to the // target of the final bit test. NextMBB = BTB.Cases[j + 1].TargetBB; } else if (j + 1 == ej) { // For the last bit test, fall through to Default. NextMBB = BTB.Default; } else { // Otherwise, fall through to the next bit test. NextMBB = BTB.Cases[j + 1].ThisBB; } emitBitTestCase(BTB, NextMBB, UnhandledProb, BTB.Reg, BTB.Cases[j], MBB); if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) { // We need to record the replacement phi edge here that normally // happens in emitBitTestCase before we delete the case, otherwise the // phi edge will be lost. addMachineCFGPred({BTB.Parent->getBasicBlock(), BTB.Cases[ej - 1].TargetBB->getBasicBlock()}, MBB); // Since we're not going to use the final bit test, remove it. BTB.Cases.pop_back(); break; } } // This is "default" BB. We have two jumps to it. From "header" BB and from // last "case" BB, unless the latter was skipped. CFGEdge HeaderToDefaultEdge = {BTB.Parent->getBasicBlock(), BTB.Default->getBasicBlock()}; addMachineCFGPred(HeaderToDefaultEdge, BTB.Parent); if (!BTB.ContiguousRange) { addMachineCFGPred(HeaderToDefaultEdge, BTB.Cases.back().ThisBB); } } SL->BitTestCases.clear(); for (auto &JTCase : SL->JTCases) { // Emit header first, if it wasn't already emitted. if (!JTCase.first.Emitted) emitJumpTableHeader(JTCase.second, JTCase.first, JTCase.first.HeaderBB); emitJumpTable(JTCase.second, JTCase.second.MBB); } SL->JTCases.clear(); for (auto &SwCase : SL->SwitchCases) emitSwitchCase(SwCase, &CurBuilder->getMBB(), *CurBuilder); SL->SwitchCases.clear(); // Check if we need to generate stack-protector guard checks. StackProtector &SP = getAnalysis(); if (SP.shouldEmitSDCheck(BB)) { bool FunctionBasedInstrumentation = TLI->getSSPStackGuardCheck(*MF->getFunction().getParent()); SPDescriptor.initialize(&BB, &MBB, FunctionBasedInstrumentation); } // Handle stack protector. if (SPDescriptor.shouldEmitFunctionBasedCheckStackProtector()) { LLVM_DEBUG(dbgs() << "Unimplemented stack protector case\n"); return false; } else if (SPDescriptor.shouldEmitStackProtector()) { MachineBasicBlock *ParentMBB = SPDescriptor.getParentMBB(); MachineBasicBlock *SuccessMBB = SPDescriptor.getSuccessMBB(); // Find the split point to split the parent mbb. At the same time copy all // physical registers used in the tail of parent mbb into virtual registers // before the split point and back into physical registers after the split // point. This prevents us needing to deal with Live-ins and many other // register allocation issues caused by us splitting the parent mbb. The // register allocator will clean up said virtual copies later on. MachineBasicBlock::iterator SplitPoint = findSplitPointForStackProtector( ParentMBB, *MF->getSubtarget().getInstrInfo()); // Splice the terminator of ParentMBB into SuccessMBB. SuccessMBB->splice(SuccessMBB->end(), ParentMBB, SplitPoint, ParentMBB->end()); // Add compare/jump on neq/jump to the parent BB. if (!emitSPDescriptorParent(SPDescriptor, ParentMBB)) return false; // CodeGen Failure MBB if we have not codegened it yet. MachineBasicBlock *FailureMBB = SPDescriptor.getFailureMBB(); if (FailureMBB->empty()) { if (!emitSPDescriptorFailure(SPDescriptor, FailureMBB)) return false; } // Clear the Per-BB State. SPDescriptor.resetPerBBState(); } return true; } bool IRTranslator::emitSPDescriptorParent(StackProtectorDescriptor &SPD, MachineBasicBlock *ParentBB) { CurBuilder->setInsertPt(*ParentBB, ParentBB->end()); // First create the loads to the guard/stack slot for the comparison. Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext()); const LLT PtrTy = getLLTForType(*PtrIRTy, *DL); LLT PtrMemTy = getLLTForMVT(TLI->getPointerMemTy(*DL)); MachineFrameInfo &MFI = ParentBB->getParent()->getFrameInfo(); int FI = MFI.getStackProtectorIndex(); Register Guard; Register StackSlotPtr = CurBuilder->buildFrameIndex(PtrTy, FI).getReg(0); const Module &M = *ParentBB->getParent()->getFunction().getParent(); Align Align = DL->getPrefTypeAlign(PointerType::getUnqual(M.getContext())); // Generate code to load the content of the guard slot. Register GuardVal = CurBuilder ->buildLoad(PtrMemTy, StackSlotPtr, MachinePointerInfo::getFixedStack(*MF, FI), Align, MachineMemOperand::MOLoad | MachineMemOperand::MOVolatile) .getReg(0); if (TLI->useStackGuardXorFP()) { LLVM_DEBUG(dbgs() << "Stack protector xor'ing with FP not yet implemented"); return false; } // Retrieve guard check function, nullptr if instrumentation is inlined. if (const Function *GuardCheckFn = TLI->getSSPStackGuardCheck(M)) { // This path is currently untestable on GlobalISel, since the only platform // that needs this seems to be Windows, and we fall back on that currently. // The code still lives here in case that changes. // Silence warning about unused variable until the code below that uses // 'GuardCheckFn' is enabled. (void)GuardCheckFn; return false; #if 0 // The target provides a guard check function to validate the guard value. // Generate a call to that function with the content of the guard slot as // argument. FunctionType *FnTy = GuardCheckFn->getFunctionType(); assert(FnTy->getNumParams() == 1 && "Invalid function signature"); ISD::ArgFlagsTy Flags; if (GuardCheckFn->hasAttribute(1, Attribute::AttrKind::InReg)) Flags.setInReg(); CallLowering::ArgInfo GuardArgInfo( {GuardVal, FnTy->getParamType(0), {Flags}}); CallLowering::CallLoweringInfo Info; Info.OrigArgs.push_back(GuardArgInfo); Info.CallConv = GuardCheckFn->getCallingConv(); Info.Callee = MachineOperand::CreateGA(GuardCheckFn, 0); Info.OrigRet = {Register(), FnTy->getReturnType()}; if (!CLI->lowerCall(MIRBuilder, Info)) { LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector check\n"); return false; } return true; #endif } // If useLoadStackGuardNode returns true, generate LOAD_STACK_GUARD. // Otherwise, emit a volatile load to retrieve the stack guard value. if (TLI->useLoadStackGuardNode()) { Guard = MRI->createGenericVirtualRegister(LLT::scalar(PtrTy.getSizeInBits())); getStackGuard(Guard, *CurBuilder); } else { // TODO: test using android subtarget when we support @llvm.thread.pointer. const Value *IRGuard = TLI->getSDagStackGuard(M); Register GuardPtr = getOrCreateVReg(*IRGuard); Guard = CurBuilder ->buildLoad(PtrMemTy, GuardPtr, MachinePointerInfo::getFixedStack(*MF, FI), Align, MachineMemOperand::MOLoad | MachineMemOperand::MOVolatile) .getReg(0); } // Perform the comparison. auto Cmp = CurBuilder->buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Guard, GuardVal); // If the guard/stackslot do not equal, branch to failure MBB. CurBuilder->buildBrCond(Cmp, *SPD.getFailureMBB()); // Otherwise branch to success MBB. CurBuilder->buildBr(*SPD.getSuccessMBB()); return true; } bool IRTranslator::emitSPDescriptorFailure(StackProtectorDescriptor &SPD, MachineBasicBlock *FailureBB) { CurBuilder->setInsertPt(*FailureBB, FailureBB->end()); const RTLIB::Libcall Libcall = RTLIB::STACKPROTECTOR_CHECK_FAIL; const char *Name = TLI->getLibcallName(Libcall); CallLowering::CallLoweringInfo Info; Info.CallConv = TLI->getLibcallCallingConv(Libcall); Info.Callee = MachineOperand::CreateES(Name); Info.OrigRet = {Register(), Type::getVoidTy(MF->getFunction().getContext()), 0}; if (!CLI->lowerCall(*CurBuilder, Info)) { LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector fail\n"); return false; } // On PS4/PS5, the "return address" must still be within the calling // function, even if it's at the very end, so emit an explicit TRAP here. // WebAssembly needs an unreachable instruction after a non-returning call, // because the function return type can be different from __stack_chk_fail's // return type (void). const TargetMachine &TM = MF->getTarget(); if (TM.getTargetTriple().isPS() || TM.getTargetTriple().isWasm()) { LLVM_DEBUG(dbgs() << "Unhandled trap emission for stack protector fail\n"); return false; } return true; } void IRTranslator::finalizeFunction() { // Release the memory used by the different maps we // needed during the translation. PendingPHIs.clear(); VMap.reset(); FrameIndices.clear(); MachinePreds.clear(); // MachineIRBuilder::DebugLoc can outlive the DILocation it holds. Clear it // to avoid accessing free’d memory (in runOnMachineFunction) and to avoid // destroying it twice (in ~IRTranslator() and ~LLVMContext()) EntryBuilder.reset(); CurBuilder.reset(); FuncInfo.clear(); SPDescriptor.resetPerFunctionState(); } /// Returns true if a BasicBlock \p BB within a variadic function contains a /// variadic musttail call. static bool checkForMustTailInVarArgFn(bool IsVarArg, const BasicBlock &BB) { if (!IsVarArg) return false; // Walk the block backwards, because tail calls usually only appear at the end // of a block. return llvm::any_of(llvm::reverse(BB), [](const Instruction &I) { const auto *CI = dyn_cast(&I); return CI && CI->isMustTailCall(); }); } bool IRTranslator::runOnMachineFunction(MachineFunction &CurMF) { MF = &CurMF; const Function &F = MF->getFunction(); GISelCSEAnalysisWrapper &Wrapper = getAnalysis().getCSEWrapper(); // Set the CSEConfig and run the analysis. GISelCSEInfo *CSEInfo = nullptr; TPC = &getAnalysis(); bool EnableCSE = EnableCSEInIRTranslator.getNumOccurrences() ? EnableCSEInIRTranslator : TPC->isGISelCSEEnabled(); TLI = MF->getSubtarget().getTargetLowering(); if (EnableCSE) { EntryBuilder = std::make_unique(CurMF); CSEInfo = &Wrapper.get(TPC->getCSEConfig()); EntryBuilder->setCSEInfo(CSEInfo); CurBuilder = std::make_unique(CurMF); CurBuilder->setCSEInfo(CSEInfo); } else { EntryBuilder = std::make_unique(); CurBuilder = std::make_unique(); } CLI = MF->getSubtarget().getCallLowering(); CurBuilder->setMF(*MF); EntryBuilder->setMF(*MF); MRI = &MF->getRegInfo(); DL = &F.getDataLayout(); ORE = std::make_unique(&F); const TargetMachine &TM = MF->getTarget(); TM.resetTargetOptions(F); EnableOpts = OptLevel != CodeGenOptLevel::None && !skipFunction(F); FuncInfo.MF = MF; if (EnableOpts) { AA = &getAnalysis().getAAResults(); FuncInfo.BPI = &getAnalysis().getBPI(); } else { AA = nullptr; FuncInfo.BPI = nullptr; } AC = &getAnalysis().getAssumptionCache( MF->getFunction()); LibInfo = &getAnalysis().getTLI(F); FuncInfo.CanLowerReturn = CLI->checkReturnTypeForCallConv(*MF); SL = std::make_unique(this, FuncInfo); SL->init(*TLI, TM, *DL); assert(PendingPHIs.empty() && "stale PHIs"); // Targets which want to use big endian can enable it using // enableBigEndian() if (!DL->isLittleEndian() && !CLI->enableBigEndian()) { // Currently we don't properly handle big endian code. OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", F.getSubprogram(), &F.getEntryBlock()); R << "unable to translate in big endian mode"; reportTranslationError(*MF, *TPC, *ORE, R); return false; } // Release the per-function state when we return, whether we succeeded or not. auto FinalizeOnReturn = make_scope_exit([this]() { finalizeFunction(); }); // Setup a separate basic-block for the arguments and constants MachineBasicBlock *EntryBB = MF->CreateMachineBasicBlock(); MF->push_back(EntryBB); EntryBuilder->setMBB(*EntryBB); DebugLoc DbgLoc = F.getEntryBlock().getFirstNonPHI()->getDebugLoc(); SwiftError.setFunction(CurMF); SwiftError.createEntriesInEntryBlock(DbgLoc); bool IsVarArg = F.isVarArg(); bool HasMustTailInVarArgFn = false; // Create all blocks, in IR order, to preserve the layout. for (const BasicBlock &BB: F) { auto *&MBB = BBToMBB[&BB]; MBB = MF->CreateMachineBasicBlock(&BB); MF->push_back(MBB); if (BB.hasAddressTaken()) MBB->setAddressTakenIRBlock(const_cast(&BB)); if (!HasMustTailInVarArgFn) HasMustTailInVarArgFn = checkForMustTailInVarArgFn(IsVarArg, BB); } MF->getFrameInfo().setHasMustTailInVarArgFunc(HasMustTailInVarArgFn); // Make our arguments/constants entry block fallthrough to the IR entry block. EntryBB->addSuccessor(&getMBB(F.front())); if (CLI->fallBackToDAGISel(*MF)) { OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", F.getSubprogram(), &F.getEntryBlock()); R << "unable to lower function: " << ore::NV("Prototype", F.getType()); reportTranslationError(*MF, *TPC, *ORE, R); return false; } // Lower the actual args into this basic block. SmallVector, 8> VRegArgs; for (const Argument &Arg: F.args()) { if (DL->getTypeStoreSize(Arg.getType()).isZero()) continue; // Don't handle zero sized types. ArrayRef VRegs = getOrCreateVRegs(Arg); VRegArgs.push_back(VRegs); if (Arg.hasSwiftErrorAttr()) { assert(VRegs.size() == 1 && "Too many vregs for Swift error"); SwiftError.setCurrentVReg(EntryBB, SwiftError.getFunctionArg(), VRegs[0]); } } if (!CLI->lowerFormalArguments(*EntryBuilder, F, VRegArgs, FuncInfo)) { OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", F.getSubprogram(), &F.getEntryBlock()); R << "unable to lower arguments: " << ore::NV("Prototype", F.getType()); reportTranslationError(*MF, *TPC, *ORE, R); return false; } // Need to visit defs before uses when translating instructions. GISelObserverWrapper WrapperObserver; if (EnableCSE && CSEInfo) WrapperObserver.addObserver(CSEInfo); { ReversePostOrderTraversal RPOT(&F); #ifndef NDEBUG DILocationVerifier Verifier; WrapperObserver.addObserver(&Verifier); #endif // ifndef NDEBUG RAIIDelegateInstaller DelInstall(*MF, &WrapperObserver); RAIIMFObserverInstaller ObsInstall(*MF, WrapperObserver); for (const BasicBlock *BB : RPOT) { MachineBasicBlock &MBB = getMBB(*BB); // Set the insertion point of all the following translations to // the end of this basic block. CurBuilder->setMBB(MBB); HasTailCall = false; for (const Instruction &Inst : *BB) { // If we translated a tail call in the last step, then we know // everything after the call is either a return, or something that is // handled by the call itself. (E.g. a lifetime marker or assume // intrinsic.) In this case, we should stop translating the block and // move on. if (HasTailCall) break; #ifndef NDEBUG Verifier.setCurrentInst(&Inst); #endif // ifndef NDEBUG // Translate any debug-info attached to the instruction. translateDbgInfo(Inst, *CurBuilder); if (translate(Inst)) continue; OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", Inst.getDebugLoc(), BB); R << "unable to translate instruction: " << ore::NV("Opcode", &Inst); if (ORE->allowExtraAnalysis("gisel-irtranslator")) { std::string InstStrStorage; raw_string_ostream InstStr(InstStrStorage); InstStr << Inst; R << ": '" << InstStrStorage << "'"; } reportTranslationError(*MF, *TPC, *ORE, R); return false; } if (!finalizeBasicBlock(*BB, MBB)) { OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure", BB->getTerminator()->getDebugLoc(), BB); R << "unable to translate basic block"; reportTranslationError(*MF, *TPC, *ORE, R); return false; } } #ifndef NDEBUG WrapperObserver.removeObserver(&Verifier); #endif } finishPendingPhis(); SwiftError.propagateVRegs(); // Merge the argument lowering and constants block with its single // successor, the LLVM-IR entry block. We want the basic block to // be maximal. assert(EntryBB->succ_size() == 1 && "Custom BB used for lowering should have only one successor"); // Get the successor of the current entry block. MachineBasicBlock &NewEntryBB = **EntryBB->succ_begin(); assert(NewEntryBB.pred_size() == 1 && "LLVM-IR entry block has a predecessor!?"); // Move all the instruction from the current entry block to the // new entry block. NewEntryBB.splice(NewEntryBB.begin(), EntryBB, EntryBB->begin(), EntryBB->end()); // Update the live-in information for the new entry block. for (const MachineBasicBlock::RegisterMaskPair &LiveIn : EntryBB->liveins()) NewEntryBB.addLiveIn(LiveIn); NewEntryBB.sortUniqueLiveIns(); // Get rid of the now empty basic block. EntryBB->removeSuccessor(&NewEntryBB); MF->remove(EntryBB); MF->deleteMachineBasicBlock(EntryBB); assert(&MF->front() == &NewEntryBB && "New entry wasn't next in the list of basic block!"); // Initialize stack protector information. StackProtector &SP = getAnalysis(); SP.copyToMachineFrameInfo(MF->getFrameInfo()); return false; }