Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- ScalarEvolutionAliasAnalysis.h - SCEV-based AA -----------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

/// \file

/// This is the interface for a SCEV-based alias analysis.

///

//===----------------------------------------------------------------------===//

#ifndef LLVM_ANALYSIS_SCALAREVOLUTIONALIASANALYSIS_H

#define LLVM_ANALYSIS_SCALAREVOLUTIONALIASANALYSIS_H

#include "llvm/Analysis/AliasAnalysis.h"

#include "llvm/Pass.h"

namespace llvm {

class Function;

class ScalarEvolution;

class SCEV;

/// A simple alias analysis implementation that uses ScalarEvolution to answer

/// queries.

class SCEVAAResult : public AAResultBase {

  ScalarEvolution &SE;

public:

  explicit SCEVAAResult(ScalarEvolution &SE) : SE(SE) {}

  SCEVAAResult(SCEVAAResult &&Arg) : AAResultBase(std::move(Arg)), SE(Arg.SE) {}

  AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB,

                    AAQueryInfo &AAQI, const Instruction *CtxI);

  bool invalidate(Function &F, const PreservedAnalyses &PA,

                  FunctionAnalysisManager::Invalidator &Inv);

private:

  Value *GetBaseValue(const SCEV *S);

};

/// Analysis pass providing a never-invalidated alias analysis result.

class SCEVAA : public AnalysisInfoMixin<SCEVAA> {

  friend AnalysisInfoMixin<SCEVAA>;

  static AnalysisKey Key;

public:

  typedef SCEVAAResult Result;

  SCEVAAResult run(Function &F, FunctionAnalysisManager &AM);

};

/// Legacy wrapper pass to provide the SCEVAAResult object.

class SCEVAAWrapperPass : public FunctionPass {

  std::unique_ptr<SCEVAAResult> Result;

public:

  static char ID;

  SCEVAAWrapperPass();

  SCEVAAResult &getResult() { return *Result; }

  const SCEVAAResult &getResult() const { return *Result; }

  bool runOnFunction(Function &F) override;

  void getAnalysisUsage(AnalysisUsage &AU) const override;

};

/// Creates an instance of \c SCEVAAWrapperPass.

FunctionPass *createSCEVAAWrapperPass();

}

#endif