1 //===- AMDGPUAliasAnalysis --------------------------------------*- 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 AMGPU address space based alias analysis pass.
10 //===----------------------------------------------------------------------===//
11 
12 #ifndef LLVM_LIB_TARGET_AMDGPU_AMDGPUALIASANALYSIS_H
13 #define LLVM_LIB_TARGET_AMDGPU_AMDGPUALIASANALYSIS_H
14 
15 #include "AMDGPU.h"
16 #include "llvm/Analysis/AliasAnalysis.h"
17 
18 namespace llvm {
19 
20 class DataLayout;
21 class MemoryLocation;
22 
23 /// A simple AA result that uses TBAA metadata to answer queries.
24 class AMDGPUAAResult : public AAResultBase<AMDGPUAAResult> {
25   friend AAResultBase<AMDGPUAAResult>;
26 
27   const DataLayout &DL;
28 
29 public:
30   explicit AMDGPUAAResult(const DataLayout &DL) : AAResultBase(), DL(DL) {}
31   AMDGPUAAResult(AMDGPUAAResult &&Arg)
32       : AAResultBase(std::move(Arg)), DL(Arg.DL) {}
33 
34   /// Handle invalidation events from the new pass manager.
35   ///
36   /// By definition, this result is stateless and so remains valid.
37   bool invalidate(Function &, const PreservedAnalyses &,
38                   FunctionAnalysisManager::Invalidator &Inv) {
39     return false;
40   }
41 
42   AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB,
43                     AAQueryInfo &AAQI);
44   bool pointsToConstantMemory(const MemoryLocation &Loc, AAQueryInfo &AAQI,
45                               bool OrLocal);
46 };
47 
48 /// Analysis pass providing a never-invalidated alias analysis result.
49 class AMDGPUAA : public AnalysisInfoMixin<AMDGPUAA> {
50   friend AnalysisInfoMixin<AMDGPUAA>;
51 
52   static AnalysisKey Key;
53 
54 public:
55   using Result = AMDGPUAAResult;
56 
57   AMDGPUAAResult run(Function &F, AnalysisManager<Function> &AM) {
58     return AMDGPUAAResult(F.getParent()->getDataLayout());
59   }
60 };
61 
62 /// Legacy wrapper pass to provide the AMDGPUAAResult object.
63 class AMDGPUAAWrapperPass : public ImmutablePass {
64   std::unique_ptr<AMDGPUAAResult> Result;
65 
66 public:
67   static char ID;
68 
69   AMDGPUAAWrapperPass() : ImmutablePass(ID) {
70     initializeAMDGPUAAWrapperPassPass(*PassRegistry::getPassRegistry());
71   }
72 
73   AMDGPUAAResult &getResult() { return *Result; }
74   const AMDGPUAAResult &getResult() const { return *Result; }
75 
76   bool doInitialization(Module &M) override {
77     Result.reset(new AMDGPUAAResult(M.getDataLayout()));
78     return false;
79   }
80 
81   bool doFinalization(Module &M) override {
82     Result.reset();
83     return false;
84   }
85 
86   void getAnalysisUsage(AnalysisUsage &AU) const override;
87 };
88 
89 // Wrapper around ExternalAAWrapperPass so that the default constructor gets the
90 // callback.
91 class AMDGPUExternalAAWrapper : public ExternalAAWrapperPass {
92 public:
93   static char ID;
94 
95   AMDGPUExternalAAWrapper() : ExternalAAWrapperPass(
96     [](Pass &P, Function &, AAResults &AAR) {
97       if (auto *WrapperPass = P.getAnalysisIfAvailable<AMDGPUAAWrapperPass>())
98         AAR.addAAResult(WrapperPass->getResult());
99     }) {}
100 };
101 
102 } // end namespace llvm
103 
104 #endif // LLVM_LIB_TARGET_AMDGPU_AMDGPUALIASANALYSIS_H
105