include/llvm/Analysis/TypeBasedAliasAnalysis.h

   1 //===- TypeBasedAliasAnalysis.h - Type-Based Alias Analysis -----*- 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 //
   9 /// \file
  10 /// This is the interface for a metadata-based TBAA. See the source file for
  11 /// details on the algorithm.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_ANALYSIS_TYPEBASEDALIASANALYSIS_H
  16 #define LLVM_ANALYSIS_TYPEBASEDALIASANALYSIS_H
  17
  18 #include "llvm/Analysis/AliasAnalysis.h"
  19 #include "llvm/IR/InstrTypes.h"
  20 #include "llvm/IR/PassManager.h"
  21 #include "llvm/Pass.h"
  22 #include <memory>
  23
  24 namespace llvm {
  25
  26 class Function;
  27 class MDNode;
  28 class MemoryLocation;
  29
  30 /// A simple AA result that uses TBAA metadata to answer queries.
  31 class TypeBasedAAResult : public AAResultBase<TypeBasedAAResult> {
  32   friend AAResultBase<TypeBasedAAResult>;
  33
  34 public:
  35   /// Handle invalidation events from the new pass manager.
  36   ///
  37   /// By definition, this result is stateless and so remains valid.
  38   bool invalidate(Function &, const PreservedAnalyses &,
  39                   FunctionAnalysisManager::Invalidator &) {
  40     return false;
  41   }
  42
  43   AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB);
  44   bool pointsToConstantMemory(const MemoryLocation &Loc, bool OrLocal);
  45   FunctionModRefBehavior getModRefBehavior(const CallBase *Call);
  46   FunctionModRefBehavior getModRefBehavior(const Function *F);
  47   ModRefInfo getModRefInfo(const CallBase *Call, const MemoryLocation &Loc);
  48   ModRefInfo getModRefInfo(const CallBase *Call1, const CallBase *Call2);
  49
  50 private:
  51   bool Aliases(const MDNode *A, const MDNode *B) const;
  52   bool PathAliases(const MDNode *A, const MDNode *B) const;
  53 };
  54
  55 /// Analysis pass providing a never-invalidated alias analysis result.
  56 class TypeBasedAA : public AnalysisInfoMixin<TypeBasedAA> {
  57   friend AnalysisInfoMixin<TypeBasedAA>;
  58
  59   static AnalysisKey Key;
  60
  61 public:
  62   using Result = TypeBasedAAResult;
  63
  64   TypeBasedAAResult run(Function &F, FunctionAnalysisManager &AM);
  65 };
  66
  67 /// Legacy wrapper pass to provide the TypeBasedAAResult object.
  68 class TypeBasedAAWrapperPass : public ImmutablePass {
  69   std::unique_ptr<TypeBasedAAResult> Result;
  70
  71 public:
  72   static char ID;
  73
  74   TypeBasedAAWrapperPass();
  75
  76   TypeBasedAAResult &getResult() { return *Result; }
  77   const TypeBasedAAResult &getResult() const { return *Result; }
  78
  79   bool doInitialization(Module &M) override;
  80   bool doFinalization(Module &M) override;
  81   void getAnalysisUsage(AnalysisUsage &AU) const override;
  82 };
  83
  84 //===--------------------------------------------------------------------===//
  85 //
  86 // createTypeBasedAAWrapperPass - This pass implements metadata-based
  87 // type-based alias analysis.
  88 //
  89 ImmutablePass *createTypeBasedAAWrapperPass();
  90
  91 } // end namespace llvm
  92
  93 #endif // LLVM_ANALYSIS_TYPEBASEDALIASANALYSIS_H