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583 lines
24 KiB
583 lines
24 KiB
//===- 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 An IRBuilder inserter that adds new instructions to the instcombine
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/// worklist.
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class LLVM_LIBRARY_VISIBILITY InstCombineIRInserter
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: public IRBuilderDefaultInserter {
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InstCombineWorklist &Worklist;
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AssumptionCache *AC;
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public:
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InstCombineIRInserter(InstCombineWorklist &WL, AssumptionCache *AC)
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: Worklist(WL), AC(AC) {}
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void InsertHelper(Instruction *I, const Twine &Name, BasicBlock *BB,
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BasicBlock::iterator InsertPt) const {
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IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt);
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Worklist.Add(I);
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using namespace llvm::PatternMatch;
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if (match(I, m_Intrinsic<Intrinsic::assume>()))
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AC->registerAssumption(cast<CallInst>(I));
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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, InstCombineIRInserter> 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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// FIXME: These can never be null and should be references.
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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 *FoldFCmp_IntToFP_Cst(FCmpInst &I, Instruction *LHSI,
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Constant *RHSC);
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Instruction *FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP,
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GlobalVariable *GV, CmpInst &ICI,
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ConstantInt *AndCst = nullptr);
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Instruction *visitFCmpInst(FCmpInst &I);
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Instruction *visitICmpInst(ICmpInst &I);
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Instruction *visitICmpInstWithCastAndCast(ICmpInst &ICI);
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Instruction *visitICmpInstWithInstAndIntCst(ICmpInst &ICI, Instruction *LHS,
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ConstantInt *RHS);
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Instruction *FoldICmpDivCst(ICmpInst &ICI, BinaryOperator *DivI,
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ConstantInt *DivRHS);
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Instruction *FoldICmpShrCst(ICmpInst &ICI, BinaryOperator *DivI,
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ConstantInt *DivRHS);
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Instruction *FoldICmpCstShrCst(ICmpInst &I, Value *Op, Value *A,
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ConstantInt *CI1, ConstantInt *CI2);
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Instruction *FoldICmpCstShlCst(ICmpInst &I, Value *Op, Value *A,
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ConstantInt *CI1, ConstantInt *CI2);
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Instruction *FoldICmpAddOpCst(Instruction &ICI, Value *X, ConstantInt *CI,
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ICmpInst::Predicate Pred);
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Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
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ICmpInst::Predicate Cond, Instruction &I);
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Instruction *FoldAllocaCmp(ICmpInst &ICI, AllocaInst *Alloca, Value *Other);
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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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/// \brief Classify whether a cast is worth optimizing.
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///
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/// Returns true if the cast from "V to Ty" actually results in any code
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/// being generated and is interesting to optimize out. If the cast can be
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/// eliminated by some other simple transformation, we prefer to do the
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/// simplification first.
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bool ShouldOptimizeCast(Instruction::CastOps opcode, const Value *V,
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Type *Ty);
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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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|
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Instruction *visitCallSite(CallSite CS);
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|
Instruction *tryOptimizeCall(CallInst *CI);
|
|
bool transformConstExprCastCall(CallSite CS);
|
|
Instruction *transformCallThroughTrampoline(CallSite CS,
|
|
IntrinsicInst *Tramp);
|
|
Instruction *transformZExtICmp(ICmpInst *ICI, Instruction &CI,
|
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bool DoXform = 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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|
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|
public:
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/// \brief Inserts an instruction \p New before instruction \p Old
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///
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/// Also adds the new instruction to the worklist and returns \p New so that
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/// it is suitable for use as the return from the visitation patterns.
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Instruction *InsertNewInstBefore(Instruction *New, Instruction &Old) {
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assert(New && !New->getParent() &&
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"New instruction already inserted into a basic block!");
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BasicBlock *BB = Old.getParent();
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BB->getInstList().insert(Old.getIterator(), New); // Insert inst
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Worklist.Add(New);
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return New;
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}
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/// \brief Same as InsertNewInstBefore, but also sets the debug loc.
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Instruction *InsertNewInstWith(Instruction *New, Instruction &Old) {
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New->setDebugLoc(Old.getDebugLoc());
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return InsertNewInstBefore(New, Old);
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}
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/// \brief A combiner-aware RAUW-like routine.
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///
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/// This method is to be used when an instruction is found to be dead,
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/// replaceable with another preexisting expression. Here we add all uses of
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/// I to the worklist, replace all uses of I with the new value, then return
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/// I, so that the inst combiner will know that I was modified.
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Instruction *replaceInstUsesWith(Instruction &I, Value *V) {
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// If there are no uses to replace, then we return nullptr to indicate that
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// no changes were made to the program.
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if (I.use_empty()) return nullptr;
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Worklist.AddUsersToWorkList(I); // Add all modified instrs to worklist.
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// If we are replacing the instruction with itself, this must be in a
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// segment of unreachable code, so just clobber the instruction.
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if (&I == V)
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V = UndefValue::get(I.getType());
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DEBUG(dbgs() << "IC: Replacing " << I << "\n"
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<< " 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 *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, Constant *Lo, Constant *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
|