616 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			616 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
//===- InstCombineInternal.h - InstCombine pass internals -------*- C++ -*-===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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/// \file
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///
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/// This file provides internal interfaces used to implement the InstCombine.
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///
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_LIB_TRANSFORMS_INSTCOMBINE_INSTCOMBINEINTERNAL_H
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#define LLVM_LIB_TRANSFORMS_INSTCOMBINE_INSTCOMBINEINTERNAL_H
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#include "llvm/Analysis/AliasAnalysis.h"
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#include "llvm/Analysis/AssumptionCache.h"
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#include "llvm/Analysis/LoopInfo.h"
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#include "llvm/Analysis/TargetFolder.h"
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#include "llvm/Analysis/ValueTracking.h"
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#include "llvm/IR/Dominators.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/InstVisitor.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Operator.h"
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#include "llvm/IR/PatternMatch.h"
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#include "llvm/Pass.h"
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#include "llvm/Transforms/InstCombine/InstCombineWorklist.h"
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#define DEBUG_TYPE "instcombine"
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namespace llvm {
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class CallSite;
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class DataLayout;
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class DominatorTree;
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class TargetLibraryInfo;
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class DbgDeclareInst;
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class MemIntrinsic;
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class MemSetInst;
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/// \brief Assign a complexity or rank value to LLVM Values.
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///
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/// This routine maps IR values to various complexity ranks:
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///   0 -> undef
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///   1 -> Constants
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///   2 -> Other non-instructions
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///   3 -> Arguments
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///   3 -> Unary operations
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///   4 -> Other instructions
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static inline unsigned getComplexity(Value *V) {
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  if (isa<Instruction>(V)) {
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    if (BinaryOperator::isNeg(V) || BinaryOperator::isFNeg(V) ||
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        BinaryOperator::isNot(V))
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      return 3;
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    return 4;
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  }
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  if (isa<Argument>(V))
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    return 3;
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  return isa<Constant>(V) ? (isa<UndefValue>(V) ? 0 : 1) : 2;
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}
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/// \brief Add one to a Constant
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static inline Constant *AddOne(Constant *C) {
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  return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1));
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}
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/// \brief Subtract one from a Constant
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static inline Constant *SubOne(Constant *C) {
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  return ConstantExpr::getSub(C, ConstantInt::get(C->getType(), 1));
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}
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/// \brief Return true if the specified value is free to invert (apply ~ to).
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/// This happens in cases where the ~ can be eliminated.  If WillInvertAllUses
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/// is true, work under the assumption that the caller intends to remove all
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/// uses of V and only keep uses of ~V.
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///
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static inline bool IsFreeToInvert(Value *V, bool WillInvertAllUses) {
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  // ~(~(X)) -> X.
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  if (BinaryOperator::isNot(V))
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    return true;
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  // Constants can be considered to be not'ed values.
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  if (isa<ConstantInt>(V))
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    return true;
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  // Compares can be inverted if all of their uses are being modified to use the
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  // ~V.
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  if (isa<CmpInst>(V))
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    return WillInvertAllUses;
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  // If `V` is of the form `A + Constant` then `-1 - V` can be folded into `(-1
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  // - Constant) - A` if we are willing to invert all of the uses.
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  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(V))
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    if (BO->getOpcode() == Instruction::Add ||
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        BO->getOpcode() == Instruction::Sub)
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      if (isa<Constant>(BO->getOperand(0)) || isa<Constant>(BO->getOperand(1)))
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        return WillInvertAllUses;
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  return false;
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}
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/// \brief Specific patterns of overflow check idioms that we match.
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enum OverflowCheckFlavor {
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  OCF_UNSIGNED_ADD,
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  OCF_SIGNED_ADD,
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  OCF_UNSIGNED_SUB,
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  OCF_SIGNED_SUB,
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  OCF_UNSIGNED_MUL,
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  OCF_SIGNED_MUL,
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  OCF_INVALID
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};
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/// \brief Returns the OverflowCheckFlavor corresponding to a overflow_with_op
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/// intrinsic.
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static inline OverflowCheckFlavor
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IntrinsicIDToOverflowCheckFlavor(unsigned ID) {
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  switch (ID) {
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  default:
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    return OCF_INVALID;
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  case Intrinsic::uadd_with_overflow:
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    return OCF_UNSIGNED_ADD;
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  case Intrinsic::sadd_with_overflow:
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    return OCF_SIGNED_ADD;
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  case Intrinsic::usub_with_overflow:
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    return OCF_UNSIGNED_SUB;
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  case Intrinsic::ssub_with_overflow:
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    return OCF_SIGNED_SUB;
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  case Intrinsic::umul_with_overflow:
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    return OCF_UNSIGNED_MUL;
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  case Intrinsic::smul_with_overflow:
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    return OCF_SIGNED_MUL;
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  }
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}
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/// \brief The core instruction combiner logic.
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///
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/// This class provides both the logic to recursively visit instructions and
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/// combine them, as well as the pass infrastructure for running this as part
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/// of the LLVM pass pipeline.
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class LLVM_LIBRARY_VISIBILITY InstCombiner
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    : public InstVisitor<InstCombiner, Instruction *> {
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  // FIXME: These members shouldn't be public.
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public:
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  /// \brief A worklist of the instructions that need to be simplified.
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  InstCombineWorklist &Worklist;
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  /// \brief An IRBuilder that automatically inserts new instructions into the
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  /// worklist.
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  typedef IRBuilder<TargetFolder, IRBuilderCallbackInserter> BuilderTy;
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  BuilderTy *Builder;
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private:
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  // Mode in which we are running the combiner.
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  const bool MinimizeSize;
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  /// Enable combines that trigger rarely but are costly in compiletime.
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  const bool ExpensiveCombines;
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  AliasAnalysis *AA;
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  // Required analyses.
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  AssumptionCache &AC;
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  TargetLibraryInfo &TLI;
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  DominatorTree &DT;
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  const DataLayout &DL;
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  // Optional analyses. When non-null, these can both be used to do better
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  // combining and will be updated to reflect any changes.
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  LoopInfo *LI;
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  bool MadeIRChange;
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public:
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  InstCombiner(InstCombineWorklist &Worklist, BuilderTy *Builder,
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               bool MinimizeSize, bool ExpensiveCombines, AliasAnalysis *AA,
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               AssumptionCache &AC, TargetLibraryInfo &TLI,
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               DominatorTree &DT, const DataLayout &DL, LoopInfo *LI)
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      : Worklist(Worklist), Builder(Builder), MinimizeSize(MinimizeSize),
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        ExpensiveCombines(ExpensiveCombines), AA(AA), AC(AC), TLI(TLI), DT(DT),
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        DL(DL), LI(LI), MadeIRChange(false) {}
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  /// \brief Run the combiner over the entire worklist until it is empty.
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  ///
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  /// \returns true if the IR is changed.
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  bool run();
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  AssumptionCache &getAssumptionCache() const { return AC; }
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  const DataLayout &getDataLayout() const { return DL; }
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  DominatorTree &getDominatorTree() const { return DT; }
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  LoopInfo *getLoopInfo() const { return LI; }
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  TargetLibraryInfo &getTargetLibraryInfo() const { return TLI; }
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  // Visitation implementation - Implement instruction combining for different
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  // instruction types.  The semantics are as follows:
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  // Return Value:
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  //    null        - No change was made
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  //     I          - Change was made, I is still valid, I may be dead though
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  //   otherwise    - Change was made, replace I with returned instruction
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  //
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  Instruction *visitAdd(BinaryOperator &I);
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  Instruction *visitFAdd(BinaryOperator &I);
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  Value *OptimizePointerDifference(Value *LHS, Value *RHS, Type *Ty);
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  Instruction *visitSub(BinaryOperator &I);
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  Instruction *visitFSub(BinaryOperator &I);
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  Instruction *visitMul(BinaryOperator &I);
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  Value *foldFMulConst(Instruction *FMulOrDiv, Constant *C,
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                       Instruction *InsertBefore);
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  Instruction *visitFMul(BinaryOperator &I);
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  Instruction *visitURem(BinaryOperator &I);
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  Instruction *visitSRem(BinaryOperator &I);
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  Instruction *visitFRem(BinaryOperator &I);
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  bool SimplifyDivRemOfSelect(BinaryOperator &I);
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  Instruction *commonRemTransforms(BinaryOperator &I);
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  Instruction *commonIRemTransforms(BinaryOperator &I);
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  Instruction *commonDivTransforms(BinaryOperator &I);
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  Instruction *commonIDivTransforms(BinaryOperator &I);
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  Instruction *visitUDiv(BinaryOperator &I);
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  Instruction *visitSDiv(BinaryOperator &I);
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  Instruction *visitFDiv(BinaryOperator &I);
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  Value *simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1, bool Inverted);
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  Value *FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS);
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  Value *FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS);
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  Instruction *visitAnd(BinaryOperator &I);
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  Value *FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, Instruction *CxtI);
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  Value *FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS);
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  Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, Value *A,
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                                   Value *B, Value *C);
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  Instruction *FoldXorWithConstants(BinaryOperator &I, Value *Op, Value *A,
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                                    Value *B, Value *C);
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  Instruction *visitOr(BinaryOperator &I);
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  Instruction *visitXor(BinaryOperator &I);
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  Instruction *visitShl(BinaryOperator &I);
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  Instruction *visitAShr(BinaryOperator &I);
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  Instruction *visitLShr(BinaryOperator &I);
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  Instruction *commonShiftTransforms(BinaryOperator &I);
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  Instruction *visitFCmpInst(FCmpInst &I);
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  Instruction *visitICmpInst(ICmpInst &I);
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  Instruction *FoldShiftByConstant(Value *Op0, Constant *Op1,
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                                   BinaryOperator &I);
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  Instruction *commonCastTransforms(CastInst &CI);
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  Instruction *commonPointerCastTransforms(CastInst &CI);
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  Instruction *visitTrunc(TruncInst &CI);
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  Instruction *visitZExt(ZExtInst &CI);
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  Instruction *visitSExt(SExtInst &CI);
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  Instruction *visitFPTrunc(FPTruncInst &CI);
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  Instruction *visitFPExt(CastInst &CI);
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  Instruction *visitFPToUI(FPToUIInst &FI);
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  Instruction *visitFPToSI(FPToSIInst &FI);
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  Instruction *visitUIToFP(CastInst &CI);
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  Instruction *visitSIToFP(CastInst &CI);
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  Instruction *visitPtrToInt(PtrToIntInst &CI);
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  Instruction *visitIntToPtr(IntToPtrInst &CI);
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  Instruction *visitBitCast(BitCastInst &CI);
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  Instruction *visitAddrSpaceCast(AddrSpaceCastInst &CI);
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  Instruction *FoldSelectOpOp(SelectInst &SI, Instruction *TI, Instruction *FI);
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  Instruction *FoldSelectIntoOp(SelectInst &SI, Value *, Value *);
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  Instruction *FoldSPFofSPF(Instruction *Inner, SelectPatternFlavor SPF1,
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                            Value *A, Value *B, Instruction &Outer,
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                            SelectPatternFlavor SPF2, Value *C);
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  Instruction *FoldItoFPtoI(Instruction &FI);
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  Instruction *visitSelectInst(SelectInst &SI);
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  Instruction *visitSelectInstWithICmp(SelectInst &SI, ICmpInst *ICI);
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  Instruction *visitCallInst(CallInst &CI);
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  Instruction *visitInvokeInst(InvokeInst &II);
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  Instruction *SliceUpIllegalIntegerPHI(PHINode &PN);
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  Instruction *visitPHINode(PHINode &PN);
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  Instruction *visitGetElementPtrInst(GetElementPtrInst &GEP);
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  Instruction *visitAllocaInst(AllocaInst &AI);
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  Instruction *visitAllocSite(Instruction &FI);
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  Instruction *visitFree(CallInst &FI);
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  Instruction *visitLoadInst(LoadInst &LI);
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  Instruction *visitStoreInst(StoreInst &SI);
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  Instruction *visitBranchInst(BranchInst &BI);
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  Instruction *visitSwitchInst(SwitchInst &SI);
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  Instruction *visitReturnInst(ReturnInst &RI);
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  Instruction *visitInsertValueInst(InsertValueInst &IV);
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  Instruction *visitInsertElementInst(InsertElementInst &IE);
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  Instruction *visitExtractElementInst(ExtractElementInst &EI);
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  Instruction *visitShuffleVectorInst(ShuffleVectorInst &SVI);
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  Instruction *visitExtractValueInst(ExtractValueInst &EV);
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  Instruction *visitLandingPadInst(LandingPadInst &LI);
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  Instruction *visitVAStartInst(VAStartInst &I);
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  Instruction *visitVACopyInst(VACopyInst &I);
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  // visitInstruction - Specify what to return for unhandled instructions...
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  Instruction *visitInstruction(Instruction &I) { return nullptr; }
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  // True when DB dominates all uses of DI execpt UI.
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  // UI must be in the same block as DI.
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  // The routine checks that the DI parent and DB are different.
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  bool dominatesAllUses(const Instruction *DI, const Instruction *UI,
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                        const BasicBlock *DB) const;
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  // Replace select with select operand SIOpd in SI-ICmp sequence when possible
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  bool replacedSelectWithOperand(SelectInst *SI, const ICmpInst *Icmp,
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                                 const unsigned SIOpd);
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private:
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  bool ShouldChangeType(unsigned FromBitWidth, unsigned ToBitWidth) const;
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  bool ShouldChangeType(Type *From, Type *To) const;
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  Value *dyn_castNegVal(Value *V) const;
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  Value *dyn_castFNegVal(Value *V, bool NoSignedZero = false) const;
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  Type *FindElementAtOffset(PointerType *PtrTy, int64_t Offset,
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                            SmallVectorImpl<Value *> &NewIndices);
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  Instruction *FoldOpIntoSelect(Instruction &Op, SelectInst *SI);
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  /// Classify whether a cast is worth optimizing.
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  ///
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  /// This is a helper to decide whether the simplification of
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  /// logic(cast(A), cast(B)) to cast(logic(A, B)) should be performed.
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  ///
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  /// \param CI The cast we are interested in.
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  ///
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  /// \return true if this cast actually results in any code being generated and
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  /// if it cannot already be eliminated by some other transformation.
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  bool shouldOptimizeCast(CastInst *CI);
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  /// \brief Try to optimize a sequence of instructions checking if an operation
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  /// on LHS and RHS overflows.
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  ///
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  /// If this overflow check is done via one of the overflow check intrinsics,
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  /// then CtxI has to be the call instruction calling that intrinsic.  If this
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  /// overflow check is done by arithmetic followed by a compare, then CtxI has
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  /// to be the arithmetic instruction.
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  ///
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  /// If a simplification is possible, stores the simplified result of the
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  /// operation in OperationResult and result of the overflow check in
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  /// OverflowResult, and return true.  If no simplification is possible,
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  /// returns false.
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  bool OptimizeOverflowCheck(OverflowCheckFlavor OCF, Value *LHS, Value *RHS,
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                             Instruction &CtxI, Value *&OperationResult,
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                             Constant *&OverflowResult);
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  Instruction *visitCallSite(CallSite CS);
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  Instruction *tryOptimizeCall(CallInst *CI);
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  bool transformConstExprCastCall(CallSite CS);
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  Instruction *transformCallThroughTrampoline(CallSite CS,
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                                              IntrinsicInst *Tramp);
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  /// Transform (zext icmp) to bitwise / integer operations in order to
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  /// eliminate it.
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  ///
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  /// \param ICI The icmp of the (zext icmp) pair we are interested in.
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  /// \parem CI The zext of the (zext icmp) pair we are interested in.
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  /// \param DoTransform Pass false to just test whether the given (zext icmp)
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  /// would be transformed. Pass true to actually perform the transformation.
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  ///
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  /// \return null if the transformation cannot be performed. If the
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  /// transformation can be performed the new instruction that replaces the
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  /// (zext icmp) pair will be returned (if \p DoTransform is false the
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  /// unmodified \p ICI will be returned in this case).
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  Instruction *transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
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                                 bool DoTransform = true);
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  Instruction *transformSExtICmp(ICmpInst *ICI, Instruction &CI);
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  bool WillNotOverflowSignedAdd(Value *LHS, Value *RHS, Instruction &CxtI);
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  bool WillNotOverflowSignedSub(Value *LHS, Value *RHS, Instruction &CxtI);
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  bool WillNotOverflowUnsignedSub(Value *LHS, Value *RHS, Instruction &CxtI);
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  bool WillNotOverflowSignedMul(Value *LHS, Value *RHS, Instruction &CxtI);
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  Value *EmitGEPOffset(User *GEP);
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  Instruction *scalarizePHI(ExtractElementInst &EI, PHINode *PN);
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  Value *EvaluateInDifferentElementOrder(Value *V, ArrayRef<int> Mask);
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  Instruction *foldCastedBitwiseLogic(BinaryOperator &I);
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  /// Determine if a pair of casts can be replaced by a single cast.
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  ///
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  /// \param CI1 The first of a pair of casts.
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  /// \param CI2 The second of a pair of casts.
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  ///
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  /// \return 0 if the cast pair cannot be eliminated, otherwise returns an
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  /// Instruction::CastOps value for a cast that can replace the pair, casting
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  /// CI1->getSrcTy() to CI2->getDstTy().
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  ///
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  /// \see CastInst::isEliminableCastPair
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  Instruction::CastOps isEliminableCastPair(const CastInst *CI1,
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                                            const CastInst *CI2);
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public:
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  /// \brief Inserts an instruction \p New before instruction \p Old
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  ///
 | 
						|
  /// Also adds the new instruction to the worklist and returns \p New so that
 | 
						|
  /// it is suitable for use as the return from the visitation patterns.
 | 
						|
  Instruction *InsertNewInstBefore(Instruction *New, Instruction &Old) {
 | 
						|
    assert(New && !New->getParent() &&
 | 
						|
           "New instruction already inserted into a basic block!");
 | 
						|
    BasicBlock *BB = Old.getParent();
 | 
						|
    BB->getInstList().insert(Old.getIterator(), New); // Insert inst
 | 
						|
    Worklist.Add(New);
 | 
						|
    return New;
 | 
						|
  }
 | 
						|
 | 
						|
  /// \brief Same as InsertNewInstBefore, but also sets the debug loc.
 | 
						|
  Instruction *InsertNewInstWith(Instruction *New, Instruction &Old) {
 | 
						|
    New->setDebugLoc(Old.getDebugLoc());
 | 
						|
    return InsertNewInstBefore(New, Old);
 | 
						|
  }
 | 
						|
 | 
						|
  /// \brief A combiner-aware RAUW-like routine.
 | 
						|
  ///
 | 
						|
  /// This method is to be used when an instruction is found to be dead,
 | 
						|
  /// replaceable 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) {
 | 
						|
    // If there are no uses to replace, then we return nullptr to indicate that
 | 
						|
    // no changes were made to the program.
 | 
						|
    if (I.use_empty()) return nullptr;
 | 
						|
 | 
						|
    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());
 | 
						|
 | 
						|
    DEBUG(dbgs() << "IC: Replacing " << I << "\n"
 | 
						|
                 << "    with " << *V << '\n');
 | 
						|
 | 
						|
    I.replaceAllUsesWith(V);
 | 
						|
    return &I;
 | 
						|
  }
 | 
						|
 | 
						|
  /// Creates a result tuple for an overflow intrinsic \p II with a given
 | 
						|
  /// \p Result and a constant \p Overflow value.
 | 
						|
  Instruction *CreateOverflowTuple(IntrinsicInst *II, Value *Result,
 | 
						|
                                   Constant *Overflow) {
 | 
						|
    Constant *V[] = {UndefValue::get(Result->getType()), Overflow};
 | 
						|
    StructType *ST = cast<StructType>(II->getType());
 | 
						|
    Constant *Struct = ConstantStruct::get(ST, V);
 | 
						|
    return InsertValueInst::Create(Struct, Result, 0);
 | 
						|
  }
 | 
						|
 | 
						|
  /// \brief Combiner aware instruction erasure.
 | 
						|
  ///
 | 
						|
  /// 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(dbgs() << "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 (Use &Operand : I.operands())
 | 
						|
        if (auto *Inst = dyn_cast<Instruction>(Operand))
 | 
						|
          Worklist.Add(Inst);
 | 
						|
    }
 | 
						|
    Worklist.Remove(&I);
 | 
						|
    I.eraseFromParent();
 | 
						|
    MadeIRChange = true;
 | 
						|
    return nullptr; // Don't do anything with FI
 | 
						|
  }
 | 
						|
 | 
						|
  void computeKnownBits(Value *V, APInt &KnownZero, APInt &KnownOne,
 | 
						|
                        unsigned Depth, Instruction *CxtI) const {
 | 
						|
    return llvm::computeKnownBits(V, KnownZero, KnownOne, DL, Depth, &AC, CxtI,
 | 
						|
                                  &DT);
 | 
						|
  }
 | 
						|
 | 
						|
  bool MaskedValueIsZero(Value *V, const APInt &Mask, unsigned Depth = 0,
 | 
						|
                         Instruction *CxtI = nullptr) const {
 | 
						|
    return llvm::MaskedValueIsZero(V, Mask, DL, Depth, &AC, CxtI, &DT);
 | 
						|
  }
 | 
						|
  unsigned ComputeNumSignBits(Value *Op, unsigned Depth = 0,
 | 
						|
                              Instruction *CxtI = nullptr) const {
 | 
						|
    return llvm::ComputeNumSignBits(Op, DL, Depth, &AC, CxtI, &DT);
 | 
						|
  }
 | 
						|
  void ComputeSignBit(Value *V, bool &KnownZero, bool &KnownOne,
 | 
						|
                      unsigned Depth = 0, Instruction *CxtI = nullptr) const {
 | 
						|
    return llvm::ComputeSignBit(V, KnownZero, KnownOne, DL, Depth, &AC, CxtI,
 | 
						|
                                &DT);
 | 
						|
  }
 | 
						|
  OverflowResult computeOverflowForUnsignedMul(Value *LHS, Value *RHS,
 | 
						|
                                               const Instruction *CxtI) {
 | 
						|
    return llvm::computeOverflowForUnsignedMul(LHS, RHS, DL, &AC, CxtI, &DT);
 | 
						|
  }
 | 
						|
  OverflowResult computeOverflowForUnsignedAdd(Value *LHS, Value *RHS,
 | 
						|
                                               const Instruction *CxtI) {
 | 
						|
    return llvm::computeOverflowForUnsignedAdd(LHS, RHS, DL, &AC, CxtI, &DT);
 | 
						|
  }
 | 
						|
 | 
						|
private:
 | 
						|
  /// \brief Performs a few simplifications for operators which are associative
 | 
						|
  /// or commutative.
 | 
						|
  bool SimplifyAssociativeOrCommutative(BinaryOperator &I);
 | 
						|
 | 
						|
  /// \brief Tries to simplify binary operations which some other binary
 | 
						|
  /// operation distributes over.
 | 
						|
  ///
 | 
						|
  /// It does this by either by factorizing out common terms (eg "(A*B)+(A*C)"
 | 
						|
  /// -> "A*(B+C)") or expanding out if this results in simplifications (eg: "A
 | 
						|
  /// & (B | C) -> (A&B) | (A&C)" if this is a win).  Returns the simplified
 | 
						|
  /// value, or null if it didn't simplify.
 | 
						|
  Value *SimplifyUsingDistributiveLaws(BinaryOperator &I);
 | 
						|
 | 
						|
  /// \brief 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,
 | 
						|
                                 Instruction *CxtI);
 | 
						|
  bool SimplifyDemandedBits(Use &U, const APInt &DemandedMask, APInt &KnownZero,
 | 
						|
                            APInt &KnownOne, unsigned Depth = 0);
 | 
						|
  /// Helper routine of SimplifyDemandedUseBits. It tries to simplify demanded
 | 
						|
  /// bit for "r1 = shr x, c1; r2 = shl r1, c2" instruction sequence.
 | 
						|
  Value *SimplifyShrShlDemandedBits(Instruction *Lsr, Instruction *Sftl,
 | 
						|
                                    const APInt &DemandedMask, APInt &KnownZero,
 | 
						|
                                    APInt &KnownOne);
 | 
						|
 | 
						|
  /// \brief Tries to simplify operands to an integer instruction based on its
 | 
						|
  /// demanded bits.
 | 
						|
  bool SimplifyDemandedInstructionBits(Instruction &Inst);
 | 
						|
 | 
						|
  Value *SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 | 
						|
                                    APInt &UndefElts, unsigned Depth = 0);
 | 
						|
 | 
						|
  Value *SimplifyVectorOp(BinaryOperator &Inst);
 | 
						|
  Value *SimplifyBSwap(BinaryOperator &Inst);
 | 
						|
 | 
						|
  // 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).
 | 
						|
  //
 | 
						|
  Instruction *FoldOpIntoPhi(Instruction &I);
 | 
						|
 | 
						|
  /// \brief Try to rotate an operation below a PHI node, using PHI nodes for
 | 
						|
  /// its operands.
 | 
						|
  Instruction *FoldPHIArgOpIntoPHI(PHINode &PN);
 | 
						|
  Instruction *FoldPHIArgBinOpIntoPHI(PHINode &PN);
 | 
						|
  Instruction *FoldPHIArgGEPIntoPHI(PHINode &PN);
 | 
						|
  Instruction *FoldPHIArgLoadIntoPHI(PHINode &PN);
 | 
						|
  Instruction *FoldPHIArgZextsIntoPHI(PHINode &PN);
 | 
						|
 | 
						|
  Instruction *foldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
 | 
						|
                           ICmpInst::Predicate Cond, Instruction &I);
 | 
						|
  Instruction *foldAllocaCmp(ICmpInst &ICI, const AllocaInst *Alloca,
 | 
						|
                             const Value *Other);
 | 
						|
  Instruction *foldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP,
 | 
						|
                                            GlobalVariable *GV, CmpInst &ICI,
 | 
						|
                                            ConstantInt *AndCst = nullptr);
 | 
						|
  Instruction *foldFCmpIntToFPConst(FCmpInst &I, Instruction *LHSI,
 | 
						|
                                    Constant *RHSC);
 | 
						|
  Instruction *foldICmpCstShrConst(ICmpInst &I, Value *Op, Value *A,
 | 
						|
                                   ConstantInt *CI1, ConstantInt *CI2);
 | 
						|
  Instruction *foldICmpCstShlConst(ICmpInst &I, Value *Op, Value *A,
 | 
						|
                                   ConstantInt *CI1, ConstantInt *CI2);
 | 
						|
  Instruction *foldICmpAddOpConst(Instruction &ICI, Value *X, ConstantInt *CI,
 | 
						|
                                  ICmpInst::Predicate Pred);
 | 
						|
  Instruction *foldICmpWithCastAndCast(ICmpInst &ICI);
 | 
						|
  Instruction *foldICmpWithConstant(ICmpInst &Cmp);
 | 
						|
 | 
						|
  Instruction *foldICmpTruncConstant(ICmpInst &Cmp, Instruction *Trunc,
 | 
						|
                                     const APInt *C);
 | 
						|
  Instruction *foldICmpAndConstant(ICmpInst &Cmp, BinaryOperator *And,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpXorConstant(ICmpInst &Cmp, BinaryOperator *Xor,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpOrConstant(ICmpInst &Cmp, BinaryOperator *Or,
 | 
						|
                                  const APInt *C);
 | 
						|
  Instruction *foldICmpMulConstant(ICmpInst &Cmp, BinaryOperator *Mul,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpShlConstant(ICmpInst &Cmp, BinaryOperator *Shl,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpShrConstant(ICmpInst &Cmp, BinaryOperator *Shr,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpUDivConstant(ICmpInst &Cmp, BinaryOperator *UDiv,
 | 
						|
                                    const APInt *C);
 | 
						|
  Instruction *foldICmpDivConstant(ICmpInst &Cmp, BinaryOperator *Div,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpSubConstant(ICmpInst &Cmp, BinaryOperator *Sub,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpAddConstant(ICmpInst &Cmp, BinaryOperator *Add,
 | 
						|
                                   const APInt *C);
 | 
						|
  Instruction *foldICmpAndConstConst(ICmpInst &Cmp, BinaryOperator *And,
 | 
						|
                                     const APInt *C1);
 | 
						|
  Instruction *foldICmpAndShift(ICmpInst &Cmp, BinaryOperator *And,
 | 
						|
                                const APInt *C1);
 | 
						|
 | 
						|
  Instruction *foldICmpEqualityWithConstant(ICmpInst &ICI);
 | 
						|
  Instruction *foldICmpIntrinsicWithConstant(ICmpInst &ICI);
 | 
						|
 | 
						|
  Instruction *OptAndOp(Instruction *Op, ConstantInt *OpRHS,
 | 
						|
                        ConstantInt *AndRHS, BinaryOperator &TheAnd);
 | 
						|
 | 
						|
  Value *FoldLogicalPlusAnd(Value *LHS, Value *RHS, ConstantInt *Mask,
 | 
						|
                            bool isSub, Instruction &I);
 | 
						|
  Value *insertRangeTest(Value *V, const APInt &Lo, const APInt &Hi,
 | 
						|
                         bool isSigned, bool Inside);
 | 
						|
  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, Type *Ty, bool isSigned);
 | 
						|
 | 
						|
  /// \brief Returns a value X such that Val = X * Scale, or null if none.
 | 
						|
  ///
 | 
						|
  /// If the multiplication is known not to overflow then NoSignedWrap is set.
 | 
						|
  Value *Descale(Value *Val, APInt Scale, bool &NoSignedWrap);
 | 
						|
};
 | 
						|
 | 
						|
} // end namespace llvm.
 | 
						|
 | 
						|
#undef DEBUG_TYPE
 | 
						|
 | 
						|
#endif
 |