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 {
30 public:
31   /// Handle invalidation events from the new pass manager.
32   ///
33   /// By definition, this result is stateless and so remains valid.
34   bool invalidate(Function &, const PreservedAnalyses &,
35                   FunctionAnalysisManager::Invalidator &) {
36     return false;
37   }
38 
39   AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB,
40                     AAQueryInfo &AAQI, const Instruction *CtxI);
41   ModRefInfo getModRefInfo(const CallBase *Call, const MemoryLocation &Loc,
42                            AAQueryInfo &AAQI);
43   ModRefInfo getModRefInfo(const CallBase *Call1, const CallBase *Call2,
44                            AAQueryInfo &AAQI);
45 
46 private:
47   bool mayAliasInScopes(const MDNode *Scopes, const MDNode *NoAlias) const;
48 };
49 
50 /// Analysis pass providing a never-invalidated alias analysis result.
51 class ScopedNoAliasAA : public AnalysisInfoMixin<ScopedNoAliasAA> {
52   friend AnalysisInfoMixin<ScopedNoAliasAA>;
53 
54   static AnalysisKey Key;
55 
56 public:
57   using Result = ScopedNoAliasAAResult;
58 
59   ScopedNoAliasAAResult run(Function &F, FunctionAnalysisManager &AM);
60 };
61 
62 /// Legacy wrapper pass to provide the ScopedNoAliasAAResult object.
63 class ScopedNoAliasAAWrapperPass : public ImmutablePass {
64   std::unique_ptr<ScopedNoAliasAAResult> Result;
65 
66 public:
67   static char ID;
68 
69   ScopedNoAliasAAWrapperPass();
70 
71   ScopedNoAliasAAResult &getResult() { return *Result; }
72   const ScopedNoAliasAAResult &getResult() const { return *Result; }
73 
74   bool doInitialization(Module &M) override;
75   bool doFinalization(Module &M) override;
76   void getAnalysisUsage(AnalysisUsage &AU) const override;
77 };
78 
79 //===--------------------------------------------------------------------===//
80 //
81 // createScopedNoAliasAAWrapperPass - This pass implements metadata-based
82 // scoped noalias analysis.
83 //
84 ImmutablePass *createScopedNoAliasAAWrapperPass();
85 
86 } // end namespace llvm
87 
88 #endif // LLVM_ANALYSIS_SCOPEDNOALIASAA_H
89