include/llvm/Analysis/ScalarEvolutionAliasAnalysis.h

   1 //===- ScalarEvolutionAliasAnalysis.h - SCEV-based AA -----------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 /// \file
   9 /// This is the interface for a SCEV-based alias analysis.
  10 ///
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_ANALYSIS_SCALAREVOLUTIONALIASANALYSIS_H
  14 #define LLVM_ANALYSIS_SCALAREVOLUTIONALIASANALYSIS_H
  15
  16 #include "llvm/Analysis/AliasAnalysis.h"
  17 #include "llvm/Analysis/ScalarEvolutionExpressions.h"
  18 #include "llvm/IR/Function.h"
  19 #include "llvm/IR/Module.h"
  20 #include "llvm/Pass.h"
  21
  22 namespace llvm {
  23
  24 /// A simple alias analysis implementation that uses ScalarEvolution to answer
  25 /// queries.
  26 class SCEVAAResult : public AAResultBase<SCEVAAResult> {
  27   ScalarEvolution &SE;
  28
  29 public:
  30   explicit SCEVAAResult(ScalarEvolution &SE) : AAResultBase(), SE(SE) {}
  31   SCEVAAResult(SCEVAAResult &&Arg) : AAResultBase(std::move(Arg)), SE(Arg.SE) {}
  32
  33   AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB);
  34
  35 private:
  36   Value *GetBaseValue(const SCEV *S);
  37 };
  38
  39 /// Analysis pass providing a never-invalidated alias analysis result.
  40 class SCEVAA : public AnalysisInfoMixin<SCEVAA> {
  41   friend AnalysisInfoMixin<SCEVAA>;
  42   static AnalysisKey Key;
  43
  44 public:
  45   typedef SCEVAAResult Result;
  46
  47   SCEVAAResult run(Function &F, FunctionAnalysisManager &AM);
  48 };
  49
  50 /// Legacy wrapper pass to provide the SCEVAAResult object.
  51 class SCEVAAWrapperPass : public FunctionPass {
  52   std::unique_ptr<SCEVAAResult> Result;
  53
  54 public:
  55   static char ID;
  56
  57   SCEVAAWrapperPass();
  58
  59   SCEVAAResult &getResult() { return *Result; }
  60   const SCEVAAResult &getResult() const { return *Result; }
  61
  62   bool runOnFunction(Function &F) override;
  63   void getAnalysisUsage(AnalysisUsage &AU) const override;
  64 };
  65
  66 /// Creates an instance of \c SCEVAAWrapperPass.
  67 FunctionPass *createSCEVAAWrapperPass();
  68
  69 }
  70
  71 #endif