From ac8f2fd2e217d063d7ef57b8698894739f707431 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 4 Jan 2010 07:12:23 +0000 Subject: [PATCH] split the instcombine class definition out to a header shared among the instcombine library. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92463 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/InstCombine/InstCombine.h | 328 ++++++++++++++++++ .../InstCombine/InstructionCombining.cpp | 300 +--------------- 2 files changed, 329 insertions(+), 299 deletions(-) create mode 100644 lib/Transforms/InstCombine/InstCombine.h diff --git a/lib/Transforms/InstCombine/InstCombine.h b/lib/Transforms/InstCombine/InstCombine.h new file mode 100644 index 00000000000..4af0236d187 --- /dev/null +++ b/lib/Transforms/InstCombine/InstCombine.h @@ -0,0 +1,328 @@ +//===- InstCombine.h - Main InstCombine pass definition -------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef INSTCOMBINE_INSTCOMBINE_H +#define INSTCOMBINE_INSTCOMBINE_H + +#include "InstCombineWorklist.h" +#include "llvm/Pass.h" +#include "llvm/Analysis/ValueTracking.h" +#include "llvm/Support/IRBuilder.h" +#include "llvm/Support/InstVisitor.h" +#include "llvm/Support/TargetFolder.h" + +namespace llvm { + class CallSite; + class TargetData; + class DbgDeclareInst; + class MemIntrinsic; + class MemSetInst; + +/// SelectPatternFlavor - We can match a variety of different patterns for +/// select operations. +enum SelectPatternFlavor { + SPF_UNKNOWN = 0, + SPF_SMIN, SPF_UMIN, + SPF_SMAX, SPF_UMAX + //SPF_ABS - TODO. +}; + + +/// InstCombineIRInserter - This is an IRBuilder insertion helper that works +/// just like the normal insertion helper, but also adds any new instructions +/// to the instcombine worklist. +class VISIBILITY_HIDDEN InstCombineIRInserter + : public IRBuilderDefaultInserter { + InstCombineWorklist &Worklist; +public: + InstCombineIRInserter(InstCombineWorklist &WL) : Worklist(WL) {} + + void InsertHelper(Instruction *I, const Twine &Name, + BasicBlock *BB, BasicBlock::iterator InsertPt) const { + IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt); + Worklist.Add(I); + } +}; + +/// InstCombiner - The -instcombine pass. +class VISIBILITY_HIDDEN InstCombiner + : public FunctionPass, + public InstVisitor { + TargetData *TD; + bool MustPreserveLCSSA; + bool MadeIRChange; +public: + /// Worklist - All of the instructions that need to be simplified. + InstCombineWorklist Worklist; + + /// Builder - This is an IRBuilder that automatically inserts new + /// instructions into the worklist when they are created. + typedef IRBuilder BuilderTy; + BuilderTy *Builder; + + static char ID; // Pass identification, replacement for typeid + InstCombiner() : FunctionPass(&ID), TD(0), Builder(0) {} + +public: + virtual bool runOnFunction(Function &F); + + bool DoOneIteration(Function &F, unsigned ItNum); + + virtual void getAnalysisUsage(AnalysisUsage &AU) const { + AU.addPreservedID(LCSSAID); + AU.setPreservesCFG(); + } + + TargetData *getTargetData() const { return TD; } + + // Visitation implementation - Implement instruction combining for different + // instruction types. The semantics are as follows: + // Return Value: + // null - No change was made + // I - Change was made, I is still valid, I may be dead though + // otherwise - Change was made, replace I with returned instruction + // + Instruction *visitAdd(BinaryOperator &I); + Instruction *visitFAdd(BinaryOperator &I); + Value *OptimizePointerDifference(Value *LHS, Value *RHS, const Type *Ty); + Instruction *visitSub(BinaryOperator &I); + Instruction *visitFSub(BinaryOperator &I); + Instruction *visitMul(BinaryOperator &I); + Instruction *visitFMul(BinaryOperator &I); + Instruction *visitURem(BinaryOperator &I); + Instruction *visitSRem(BinaryOperator &I); + Instruction *visitFRem(BinaryOperator &I); + bool SimplifyDivRemOfSelect(BinaryOperator &I); + Instruction *commonRemTransforms(BinaryOperator &I); + Instruction *commonIRemTransforms(BinaryOperator &I); + Instruction *commonDivTransforms(BinaryOperator &I); + Instruction *commonIDivTransforms(BinaryOperator &I); + Instruction *visitUDiv(BinaryOperator &I); + Instruction *visitSDiv(BinaryOperator &I); + Instruction *visitFDiv(BinaryOperator &I); + Instruction *FoldAndOfICmps(Instruction &I, ICmpInst *LHS, ICmpInst *RHS); + Instruction *FoldAndOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); + Instruction *visitAnd(BinaryOperator &I); + Instruction *FoldOrOfICmps(Instruction &I, ICmpInst *LHS, ICmpInst *RHS); + Instruction *FoldOrOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); + Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, + Value *A, Value *B, Value *C); + Instruction *visitOr (BinaryOperator &I); + Instruction *visitXor(BinaryOperator &I); + Instruction *visitShl(BinaryOperator &I); + Instruction *visitAShr(BinaryOperator &I); + Instruction *visitLShr(BinaryOperator &I); + Instruction *commonShiftTransforms(BinaryOperator &I); + Instruction *FoldFCmp_IntToFP_Cst(FCmpInst &I, Instruction *LHSI, + Constant *RHSC); + Instruction *FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, + GlobalVariable *GV, CmpInst &ICI, + ConstantInt *AndCst = 0); + Instruction *visitFCmpInst(FCmpInst &I); + Instruction *visitICmpInst(ICmpInst &I); + Instruction *visitICmpInstWithCastAndCast(ICmpInst &ICI); + Instruction *visitICmpInstWithInstAndIntCst(ICmpInst &ICI, + Instruction *LHS, + ConstantInt *RHS); + Instruction *FoldICmpDivCst(ICmpInst &ICI, BinaryOperator *DivI, + ConstantInt *DivRHS); + Instruction *FoldICmpAddOpCst(ICmpInst &ICI, Value *X, ConstantInt *CI, + ICmpInst::Predicate Pred, Value *TheAdd); + Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS, + ICmpInst::Predicate Cond, Instruction &I); + Instruction *FoldShiftByConstant(Value *Op0, ConstantInt *Op1, + BinaryOperator &I); + Instruction *commonCastTransforms(CastInst &CI); + Instruction *commonIntCastTransforms(CastInst &CI); + Instruction *commonPointerCastTransforms(CastInst &CI); + Instruction *visitTrunc(TruncInst &CI); + Instruction *visitZExt(ZExtInst &CI); + Instruction *visitSExt(SExtInst &CI); + Instruction *visitFPTrunc(FPTruncInst &CI); + Instruction *visitFPExt(CastInst &CI); + Instruction *visitFPToUI(FPToUIInst &FI); + Instruction *visitFPToSI(FPToSIInst &FI); + Instruction *visitUIToFP(CastInst &CI); + Instruction *visitSIToFP(CastInst &CI); + Instruction *visitPtrToInt(PtrToIntInst &CI); + Instruction *visitIntToPtr(IntToPtrInst &CI); + Instruction *visitBitCast(BitCastInst &CI); + Instruction *FoldSelectOpOp(SelectInst &SI, Instruction *TI, + Instruction *FI); + Instruction *FoldSelectIntoOp(SelectInst &SI, Value*, Value*); + Instruction *FoldSPFofSPF(Instruction *Inner, SelectPatternFlavor SPF1, + Value *A, Value *B, Instruction &Outer, + SelectPatternFlavor SPF2, Value *C); + Instruction *visitSelectInst(SelectInst &SI); + Instruction *visitSelectInstWithICmp(SelectInst &SI, ICmpInst *ICI); + Instruction *visitCallInst(CallInst &CI); + Instruction *visitInvokeInst(InvokeInst &II); + + Instruction *SliceUpIllegalIntegerPHI(PHINode &PN); + Instruction *visitPHINode(PHINode &PN); + Instruction *visitGetElementPtrInst(GetElementPtrInst &GEP); + Instruction *visitAllocaInst(AllocaInst &AI); + Instruction *visitFree(Instruction &FI); + Instruction *visitLoadInst(LoadInst &LI); + Instruction *visitStoreInst(StoreInst &SI); + Instruction *visitBranchInst(BranchInst &BI); + Instruction *visitSwitchInst(SwitchInst &SI); + Instruction *visitInsertElementInst(InsertElementInst &IE); + Instruction *visitExtractElementInst(ExtractElementInst &EI); + Instruction *visitShuffleVectorInst(ShuffleVectorInst &SVI); + Instruction *visitExtractValueInst(ExtractValueInst &EV); + + // visitInstruction - Specify what to return for unhandled instructions... + Instruction *visitInstruction(Instruction &I) { return 0; } + +private: + Instruction *visitCallSite(CallSite CS); + bool transformConstExprCastCall(CallSite CS); + Instruction *transformCallThroughTrampoline(CallSite CS); + Instruction *transformZExtICmp(ICmpInst *ICI, Instruction &CI, + bool DoXform = true); + bool WillNotOverflowSignedAdd(Value *LHS, Value *RHS); + DbgDeclareInst *hasOneUsePlusDeclare(Value *V); + + +public: + // InsertNewInstBefore - insert an instruction New before instruction Old + // in the program. Add the new instruction to the worklist. + // + Instruction *InsertNewInstBefore(Instruction *New, Instruction &Old) { + assert(New && New->getParent() == 0 && + "New instruction already inserted into a basic block!"); + BasicBlock *BB = Old.getParent(); + BB->getInstList().insert(&Old, New); // Insert inst + Worklist.Add(New); + return New; + } + + // ReplaceInstUsesWith - This method is to be used when an instruction is + // found to be dead, replacable with another preexisting expression. Here + // we add all uses of I to the worklist, replace all uses of I with the new + // value, then return I, so that the inst combiner will know that I was + // modified. + // + Instruction *ReplaceInstUsesWith(Instruction &I, Value *V) { + Worklist.AddUsersToWorkList(I); // Add all modified instrs to worklist. + + // If we are replacing the instruction with itself, this must be in a + // segment of unreachable code, so just clobber the instruction. + if (&I == V) + V = UndefValue::get(I.getType()); + + I.replaceAllUsesWith(V); + return &I; + } + + // EraseInstFromFunction - When dealing with an instruction that has side + // effects or produces a void value, we can't rely on DCE to delete the + // instruction. Instead, visit methods should return the value returned by + // this function. + Instruction *EraseInstFromFunction(Instruction &I) { + DEBUG(errs() << "IC: ERASE " << I << '\n'); + + assert(I.use_empty() && "Cannot erase instruction that is used!"); + // Make sure that we reprocess all operands now that we reduced their + // use counts. + if (I.getNumOperands() < 8) { + for (User::op_iterator i = I.op_begin(), e = I.op_end(); i != e; ++i) + if (Instruction *Op = dyn_cast(*i)) + Worklist.Add(Op); + } + Worklist.Remove(&I); + I.eraseFromParent(); + MadeIRChange = true; + return 0; // Don't do anything with FI + } + + void ComputeMaskedBits(Value *V, const APInt &Mask, APInt &KnownZero, + APInt &KnownOne, unsigned Depth = 0) const { + return llvm::ComputeMaskedBits(V, Mask, KnownZero, KnownOne, TD, Depth); + } + + bool MaskedValueIsZero(Value *V, const APInt &Mask, + unsigned Depth = 0) const { + return llvm::MaskedValueIsZero(V, Mask, TD, Depth); + } + unsigned ComputeNumSignBits(Value *Op, unsigned Depth = 0) const { + return llvm::ComputeNumSignBits(Op, TD, Depth); + } + +private: + + /// SimplifyCommutative - This performs a few simplifications for + /// commutative operators. + bool SimplifyCommutative(BinaryOperator &I); + + /// SimplifyDemandedUseBits - Attempts to replace V with a simpler value + /// based on the demanded bits. + Value *SimplifyDemandedUseBits(Value *V, APInt DemandedMask, + APInt& KnownZero, APInt& KnownOne, + unsigned Depth); + bool SimplifyDemandedBits(Use &U, APInt DemandedMask, + APInt& KnownZero, APInt& KnownOne, + unsigned Depth=0); + + /// SimplifyDemandedInstructionBits - Inst is an integer instruction that + /// SimplifyDemandedBits knows about. See if the instruction has any + /// properties that allow us to simplify its operands. + bool SimplifyDemandedInstructionBits(Instruction &Inst); + + Value *SimplifyDemandedVectorElts(Value *V, APInt DemandedElts, + APInt& UndefElts, unsigned Depth = 0); + + // FoldOpIntoPhi - Given a binary operator, cast instruction, or select + // which has a PHI node as operand #0, see if we can fold the instruction + // into the PHI (which is only possible if all operands to the PHI are + // constants). + // + // If AllowAggressive is true, FoldOpIntoPhi will allow certain transforms + // that would normally be unprofitable because they strongly encourage jump + // threading. + Instruction *FoldOpIntoPhi(Instruction &I, bool AllowAggressive = false); + + // FoldPHIArgOpIntoPHI - If all operands to a PHI node are the same "unary" + // operator and they all are only used by the PHI, PHI together their + // inputs, and do the operation once, to the result of the PHI. + Instruction *FoldPHIArgOpIntoPHI(PHINode &PN); + Instruction *FoldPHIArgBinOpIntoPHI(PHINode &PN); + Instruction *FoldPHIArgGEPIntoPHI(PHINode &PN); + Instruction *FoldPHIArgLoadIntoPHI(PHINode &PN); + + + Instruction *OptAndOp(Instruction *Op, ConstantInt *OpRHS, + ConstantInt *AndRHS, BinaryOperator &TheAnd); + + Value *FoldLogicalPlusAnd(Value *LHS, Value *RHS, ConstantInt *Mask, + bool isSub, Instruction &I); + Instruction *InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, + bool isSigned, bool Inside, Instruction &IB); + Instruction *PromoteCastOfAllocation(BitCastInst &CI, AllocaInst &AI); + Instruction *MatchBSwap(BinaryOperator &I); + bool SimplifyStoreAtEndOfBlock(StoreInst &SI); + Instruction *SimplifyMemTransfer(MemIntrinsic *MI); + Instruction *SimplifyMemSet(MemSetInst *MI); + + + Value *EvaluateInDifferentType(Value *V, const Type *Ty, bool isSigned); + + bool CanEvaluateInDifferentType(Value *V, const Type *Ty, + unsigned CastOpc, int &NumCastsRemoved); + unsigned GetOrEnforceKnownAlignment(Value *V, + unsigned PrefAlign = 0); + +}; + + + +} // end namespace llvm. + +#endif diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp index 609bbc04109..13f0ac6f7c9 100644 --- a/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -35,7 +35,7 @@ #define DEBUG_TYPE "instcombine" #include "llvm/Transforms/Scalar.h" -#include "InstCombineWorklist.h" +#include "InstCombine.h" #include "llvm/IntrinsicInst.h" #include "llvm/LLVMContext.h" #include "llvm/Pass.h" @@ -73,304 +73,6 @@ STATISTIC(NumDeadInst , "Number of dead inst eliminated"); STATISTIC(NumDeadStore, "Number of dead stores eliminated"); STATISTIC(NumSunkInst , "Number of instructions sunk"); -/// SelectPatternFlavor - We can match a variety of different patterns for -/// select operations. -enum SelectPatternFlavor { - SPF_UNKNOWN = 0, - SPF_SMIN, SPF_UMIN, - SPF_SMAX, SPF_UMAX - //SPF_ABS - TODO. -}; - - -namespace { - /// InstCombineIRInserter - This is an IRBuilder insertion helper that works - /// just like the normal insertion helper, but also adds any new instructions - /// to the instcombine worklist. - class InstCombineIRInserter : public IRBuilderDefaultInserter { - InstCombineWorklist &Worklist; - public: - InstCombineIRInserter(InstCombineWorklist &WL) : Worklist(WL) {} - - void InsertHelper(Instruction *I, const Twine &Name, - BasicBlock *BB, BasicBlock::iterator InsertPt) const { - IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt); - Worklist.Add(I); - } - }; -} // end anonymous namespace - - -namespace { - class InstCombiner : public FunctionPass, - public InstVisitor { - TargetData *TD; - bool MustPreserveLCSSA; - bool MadeIRChange; - public: - /// Worklist - All of the instructions that need to be simplified. - InstCombineWorklist Worklist; - - /// Builder - This is an IRBuilder that automatically inserts new - /// instructions into the worklist when they are created. - typedef IRBuilder BuilderTy; - BuilderTy *Builder; - - static char ID; // Pass identification, replacement for typeid - InstCombiner() : FunctionPass(&ID), TD(0), Builder(0) {} - - public: - virtual bool runOnFunction(Function &F); - - bool DoOneIteration(Function &F, unsigned ItNum); - - virtual void getAnalysisUsage(AnalysisUsage &AU) const { - AU.addPreservedID(LCSSAID); - AU.setPreservesCFG(); - } - - TargetData *getTargetData() const { return TD; } - - // Visitation implementation - Implement instruction combining for different - // instruction types. The semantics are as follows: - // Return Value: - // null - No change was made - // I - Change was made, I is still valid, I may be dead though - // otherwise - Change was made, replace I with returned instruction - // - Instruction *visitAdd(BinaryOperator &I); - Instruction *visitFAdd(BinaryOperator &I); - Value *OptimizePointerDifference(Value *LHS, Value *RHS, const Type *Ty); - Instruction *visitSub(BinaryOperator &I); - Instruction *visitFSub(BinaryOperator &I); - Instruction *visitMul(BinaryOperator &I); - Instruction *visitFMul(BinaryOperator &I); - Instruction *visitURem(BinaryOperator &I); - Instruction *visitSRem(BinaryOperator &I); - Instruction *visitFRem(BinaryOperator &I); - bool SimplifyDivRemOfSelect(BinaryOperator &I); - Instruction *commonRemTransforms(BinaryOperator &I); - Instruction *commonIRemTransforms(BinaryOperator &I); - Instruction *commonDivTransforms(BinaryOperator &I); - Instruction *commonIDivTransforms(BinaryOperator &I); - Instruction *visitUDiv(BinaryOperator &I); - Instruction *visitSDiv(BinaryOperator &I); - Instruction *visitFDiv(BinaryOperator &I); - Instruction *FoldAndOfICmps(Instruction &I, ICmpInst *LHS, ICmpInst *RHS); - Instruction *FoldAndOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); - Instruction *visitAnd(BinaryOperator &I); - Instruction *FoldOrOfICmps(Instruction &I, ICmpInst *LHS, ICmpInst *RHS); - Instruction *FoldOrOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); - Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, - Value *A, Value *B, Value *C); - Instruction *visitOr (BinaryOperator &I); - Instruction *visitXor(BinaryOperator &I); - Instruction *visitShl(BinaryOperator &I); - Instruction *visitAShr(BinaryOperator &I); - Instruction *visitLShr(BinaryOperator &I); - Instruction *commonShiftTransforms(BinaryOperator &I); - Instruction *FoldFCmp_IntToFP_Cst(FCmpInst &I, Instruction *LHSI, - Constant *RHSC); - Instruction *FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, - GlobalVariable *GV, CmpInst &ICI, - ConstantInt *AndCst = 0); - Instruction *visitFCmpInst(FCmpInst &I); - Instruction *visitICmpInst(ICmpInst &I); - Instruction *visitICmpInstWithCastAndCast(ICmpInst &ICI); - Instruction *visitICmpInstWithInstAndIntCst(ICmpInst &ICI, - Instruction *LHS, - ConstantInt *RHS); - Instruction *FoldICmpDivCst(ICmpInst &ICI, BinaryOperator *DivI, - ConstantInt *DivRHS); - Instruction *FoldICmpAddOpCst(ICmpInst &ICI, Value *X, ConstantInt *CI, - ICmpInst::Predicate Pred, Value *TheAdd); - Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS, - ICmpInst::Predicate Cond, Instruction &I); - Instruction *FoldShiftByConstant(Value *Op0, ConstantInt *Op1, - BinaryOperator &I); - Instruction *commonCastTransforms(CastInst &CI); - Instruction *commonIntCastTransforms(CastInst &CI); - Instruction *commonPointerCastTransforms(CastInst &CI); - Instruction *visitTrunc(TruncInst &CI); - Instruction *visitZExt(ZExtInst &CI); - Instruction *visitSExt(SExtInst &CI); - Instruction *visitFPTrunc(FPTruncInst &CI); - Instruction *visitFPExt(CastInst &CI); - Instruction *visitFPToUI(FPToUIInst &FI); - Instruction *visitFPToSI(FPToSIInst &FI); - Instruction *visitUIToFP(CastInst &CI); - Instruction *visitSIToFP(CastInst &CI); - Instruction *visitPtrToInt(PtrToIntInst &CI); - Instruction *visitIntToPtr(IntToPtrInst &CI); - Instruction *visitBitCast(BitCastInst &CI); - Instruction *FoldSelectOpOp(SelectInst &SI, Instruction *TI, - Instruction *FI); - Instruction *FoldSelectIntoOp(SelectInst &SI, Value*, Value*); - Instruction *FoldSPFofSPF(Instruction *Inner, SelectPatternFlavor SPF1, - Value *A, Value *B, Instruction &Outer, - SelectPatternFlavor SPF2, Value *C); - Instruction *visitSelectInst(SelectInst &SI); - Instruction *visitSelectInstWithICmp(SelectInst &SI, ICmpInst *ICI); - Instruction *visitCallInst(CallInst &CI); - Instruction *visitInvokeInst(InvokeInst &II); - - Instruction *SliceUpIllegalIntegerPHI(PHINode &PN); - Instruction *visitPHINode(PHINode &PN); - Instruction *visitGetElementPtrInst(GetElementPtrInst &GEP); - Instruction *visitAllocaInst(AllocaInst &AI); - Instruction *visitFree(Instruction &FI); - Instruction *visitLoadInst(LoadInst &LI); - Instruction *visitStoreInst(StoreInst &SI); - Instruction *visitBranchInst(BranchInst &BI); - Instruction *visitSwitchInst(SwitchInst &SI); - Instruction *visitInsertElementInst(InsertElementInst &IE); - Instruction *visitExtractElementInst(ExtractElementInst &EI); - Instruction *visitShuffleVectorInst(ShuffleVectorInst &SVI); - Instruction *visitExtractValueInst(ExtractValueInst &EV); - - // visitInstruction - Specify what to return for unhandled instructions... - Instruction *visitInstruction(Instruction &I) { return 0; } - - private: - Instruction *visitCallSite(CallSite CS); - bool transformConstExprCastCall(CallSite CS); - Instruction *transformCallThroughTrampoline(CallSite CS); - Instruction *transformZExtICmp(ICmpInst *ICI, Instruction &CI, - bool DoXform = true); - bool WillNotOverflowSignedAdd(Value *LHS, Value *RHS); - DbgDeclareInst *hasOneUsePlusDeclare(Value *V); - - - public: - // InsertNewInstBefore - insert an instruction New before instruction Old - // in the program. Add the new instruction to the worklist. - // - Instruction *InsertNewInstBefore(Instruction *New, Instruction &Old) { - assert(New && New->getParent() == 0 && - "New instruction already inserted into a basic block!"); - BasicBlock *BB = Old.getParent(); - BB->getInstList().insert(&Old, New); // Insert inst - Worklist.Add(New); - return New; - } - - // ReplaceInstUsesWith - This method is to be used when an instruction is - // found to be dead, replacable with another preexisting expression. Here - // we add all uses of I to the worklist, replace all uses of I with the new - // value, then return I, so that the inst combiner will know that I was - // modified. - // - Instruction *ReplaceInstUsesWith(Instruction &I, Value *V) { - Worklist.AddUsersToWorkList(I); // Add all modified instrs to worklist. - - // If we are replacing the instruction with itself, this must be in a - // segment of unreachable code, so just clobber the instruction. - if (&I == V) - V = UndefValue::get(I.getType()); - - I.replaceAllUsesWith(V); - return &I; - } - - // EraseInstFromFunction - When dealing with an instruction that has side - // effects or produces a void value, we can't rely on DCE to delete the - // instruction. Instead, visit methods should return the value returned by - // this function. - Instruction *EraseInstFromFunction(Instruction &I) { - DEBUG(errs() << "IC: ERASE " << I << '\n'); - - assert(I.use_empty() && "Cannot erase instruction that is used!"); - // Make sure that we reprocess all operands now that we reduced their - // use counts. - if (I.getNumOperands() < 8) { - for (User::op_iterator i = I.op_begin(), e = I.op_end(); i != e; ++i) - if (Instruction *Op = dyn_cast(*i)) - Worklist.Add(Op); - } - Worklist.Remove(&I); - I.eraseFromParent(); - MadeIRChange = true; - return 0; // Don't do anything with FI - } - - void ComputeMaskedBits(Value *V, const APInt &Mask, APInt &KnownZero, - APInt &KnownOne, unsigned Depth = 0) const { - return llvm::ComputeMaskedBits(V, Mask, KnownZero, KnownOne, TD, Depth); - } - - bool MaskedValueIsZero(Value *V, const APInt &Mask, - unsigned Depth = 0) const { - return llvm::MaskedValueIsZero(V, Mask, TD, Depth); - } - unsigned ComputeNumSignBits(Value *Op, unsigned Depth = 0) const { - return llvm::ComputeNumSignBits(Op, TD, Depth); - } - - private: - - /// SimplifyCommutative - This performs a few simplifications for - /// commutative operators. - bool SimplifyCommutative(BinaryOperator &I); - - /// SimplifyDemandedUseBits - Attempts to replace V with a simpler value - /// based on the demanded bits. - Value *SimplifyDemandedUseBits(Value *V, APInt DemandedMask, - APInt& KnownZero, APInt& KnownOne, - unsigned Depth); - bool SimplifyDemandedBits(Use &U, APInt DemandedMask, - APInt& KnownZero, APInt& KnownOne, - unsigned Depth=0); - - /// SimplifyDemandedInstructionBits - Inst is an integer instruction that - /// SimplifyDemandedBits knows about. See if the instruction has any - /// properties that allow us to simplify its operands. - bool SimplifyDemandedInstructionBits(Instruction &Inst); - - Value *SimplifyDemandedVectorElts(Value *V, APInt DemandedElts, - APInt& UndefElts, unsigned Depth = 0); - - // FoldOpIntoPhi - Given a binary operator, cast instruction, or select - // which has a PHI node as operand #0, see if we can fold the instruction - // into the PHI (which is only possible if all operands to the PHI are - // constants). - // - // If AllowAggressive is true, FoldOpIntoPhi will allow certain transforms - // that would normally be unprofitable because they strongly encourage jump - // threading. - Instruction *FoldOpIntoPhi(Instruction &I, bool AllowAggressive = false); - - // FoldPHIArgOpIntoPHI - If all operands to a PHI node are the same "unary" - // operator and they all are only used by the PHI, PHI together their - // inputs, and do the operation once, to the result of the PHI. - Instruction *FoldPHIArgOpIntoPHI(PHINode &PN); - Instruction *FoldPHIArgBinOpIntoPHI(PHINode &PN); - Instruction *FoldPHIArgGEPIntoPHI(PHINode &PN); - Instruction *FoldPHIArgLoadIntoPHI(PHINode &PN); - - - Instruction *OptAndOp(Instruction *Op, ConstantInt *OpRHS, - ConstantInt *AndRHS, BinaryOperator &TheAnd); - - Value *FoldLogicalPlusAnd(Value *LHS, Value *RHS, ConstantInt *Mask, - bool isSub, Instruction &I); - Instruction *InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, - bool isSigned, bool Inside, Instruction &IB); - Instruction *PromoteCastOfAllocation(BitCastInst &CI, AllocaInst &AI); - Instruction *MatchBSwap(BinaryOperator &I); - bool SimplifyStoreAtEndOfBlock(StoreInst &SI); - Instruction *SimplifyMemTransfer(MemIntrinsic *MI); - Instruction *SimplifyMemSet(MemSetInst *MI); - - - Value *EvaluateInDifferentType(Value *V, const Type *Ty, bool isSigned); - - bool CanEvaluateInDifferentType(Value *V, const Type *Ty, - unsigned CastOpc, int &NumCastsRemoved); - unsigned GetOrEnforceKnownAlignment(Value *V, - unsigned PrefAlign = 0); - - }; -} // end anonymous namespace char InstCombiner::ID = 0; static RegisterPass -- 2.34.1