1 //===- ScopedNoAliasAA.h - Scoped No-Alias 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 scoped no-alias analysis.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_ANALYSIS_SCOPEDNOALIASAA_H
15 #define LLVM_ANALYSIS_SCOPEDNOALIASAA_H
16 
17 #include "llvm/Analysis/AliasAnalysis.h"
18 #include "llvm/IR/PassManager.h"
19 #include "llvm/Pass.h"
20 #include <memory>
21 
22 namespace llvm {
23 
24 class Function;
25 class MDNode;
26 class MemoryLocation;
27 
28 /// A simple AA result which uses scoped-noalias metadata to answer queries.
29 class ScopedNoAliasAAResult : public AAResultBase<ScopedNoAliasAAResult> {
30   friend AAResultBase<ScopedNoAliasAAResult>;
31 
32 public:
33   /// Handle invalidation events from the new pass manager.
34   ///
35   /// By definition, this result is stateless and so remains valid.
invalidate(Function &,const PreservedAnalyses &,FunctionAnalysisManager::Invalidator &)36   bool invalidate(Function &, const PreservedAnalyses &,
37                   FunctionAnalysisManager::Invalidator &) {
38     return false;
39   }
40 
41   AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB,
42                     AAQueryInfo &AAQI);
43   ModRefInfo getModRefInfo(const CallBase *Call, const MemoryLocation &Loc,
44                            AAQueryInfo &AAQI);
45   ModRefInfo getModRefInfo(const CallBase *Call1, const CallBase *Call2,
46                            AAQueryInfo &AAQI);
47 
48 private:
49   bool mayAliasInScopes(const MDNode *Scopes, const MDNode *NoAlias) const;
50 };
51 
52 /// Analysis pass providing a never-invalidated alias analysis result.
53 class ScopedNoAliasAA : public AnalysisInfoMixin<ScopedNoAliasAA> {
54   friend AnalysisInfoMixin<ScopedNoAliasAA>;
55 
56   static AnalysisKey Key;
57 
58 public:
59   using Result = ScopedNoAliasAAResult;
60 
61   ScopedNoAliasAAResult run(Function &F, FunctionAnalysisManager &AM);
62 };
63 
64 /// Legacy wrapper pass to provide the ScopedNoAliasAAResult object.
65 class ScopedNoAliasAAWrapperPass : public ImmutablePass {
66   std::unique_ptr<ScopedNoAliasAAResult> Result;
67 
68 public:
69   static char ID;
70 
71   ScopedNoAliasAAWrapperPass();
72 
getResult()73   ScopedNoAliasAAResult &getResult() { return *Result; }
getResult()74   const ScopedNoAliasAAResult &getResult() const { return *Result; }
75 
76   bool doInitialization(Module &M) override;
77   bool doFinalization(Module &M) override;
78   void getAnalysisUsage(AnalysisUsage &AU) const override;
79 };
80 
81 //===--------------------------------------------------------------------===//
82 //
83 // createScopedNoAliasAAWrapperPass - This pass implements metadata-based
84 // scoped noalias analysis.
85 //
86 ImmutablePass *createScopedNoAliasAAWrapperPass();
87 
88 } // end namespace llvm
89 
90 #endif // LLVM_ANALYSIS_SCOPEDNOALIASAA_H
91