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| Rev | Author | Line No. | Line |
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| 14 | pmbaty | 1 | //===- ObjCARCAliasAnalysis.h - ObjC ARC Alias Analysis ---------*- C++ -*-===// |
| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | /// \file |
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| 9 | /// This file declares a simple ARC-aware AliasAnalysis using special knowledge |
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| 10 | /// of Objective C to enhance other optimization passes which rely on the Alias |
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| 11 | /// Analysis infrastructure. |
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| 12 | /// |
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| 13 | /// WARNING: This file knows about certain library functions. It recognizes them |
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| 14 | /// by name, and hardwires knowledge of their semantics. |
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| 15 | /// |
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| 16 | /// WARNING: This file knows about how certain Objective-C library functions are |
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| 17 | /// used. Naive LLVM IR transformations which would otherwise be |
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| 18 | /// behavior-preserving may break these assumptions. |
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| 19 | /// |
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| 20 | //===----------------------------------------------------------------------===// |
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| 21 | |||
| 22 | #ifndef LLVM_ANALYSIS_OBJCARCALIASANALYSIS_H |
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| 23 | #define LLVM_ANALYSIS_OBJCARCALIASANALYSIS_H |
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| 24 | |||
| 25 | #include "llvm/Analysis/AliasAnalysis.h" |
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| 26 | #include "llvm/Pass.h" |
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| 27 | |||
| 28 | namespace llvm { |
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| 29 | namespace objcarc { |
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| 30 | |||
| 31 | /// This is a simple alias analysis implementation that uses knowledge |
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| 32 | /// of ARC constructs to answer queries. |
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| 33 | /// |
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| 34 | /// TODO: This class could be generalized to know about other ObjC-specific |
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| 35 | /// tricks. Such as knowing that ivars in the non-fragile ABI are non-aliasing |
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| 36 | /// even though their offsets are dynamic. |
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| 37 | class ObjCARCAAResult : public AAResultBase { |
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| 38 | const DataLayout &DL; |
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| 39 | |||
| 40 | public: |
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| 41 | explicit ObjCARCAAResult(const DataLayout &DL) : DL(DL) {} |
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| 42 | ObjCARCAAResult(ObjCARCAAResult &&Arg) |
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| 43 | : AAResultBase(std::move(Arg)), DL(Arg.DL) {} |
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| 44 | |||
| 45 | /// Handle invalidation events from the new pass manager. |
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| 46 | /// |
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| 47 | /// By definition, this result is stateless and so remains valid. |
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| 48 | bool invalidate(Function &, const PreservedAnalyses &, |
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| 49 | FunctionAnalysisManager::Invalidator &) { |
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| 50 | return false; |
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| 51 | } |
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| 52 | |||
| 53 | AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB, |
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| 54 | AAQueryInfo &AAQI, const Instruction *CtxI); |
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| 55 | ModRefInfo getModRefInfoMask(const MemoryLocation &Loc, AAQueryInfo &AAQI, |
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| 56 | bool IgnoreLocals); |
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| 57 | |||
| 58 | using AAResultBase::getMemoryEffects; |
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| 59 | MemoryEffects getMemoryEffects(const Function *F); |
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| 60 | |||
| 61 | using AAResultBase::getModRefInfo; |
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| 62 | ModRefInfo getModRefInfo(const CallBase *Call, const MemoryLocation &Loc, |
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| 63 | AAQueryInfo &AAQI); |
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| 64 | }; |
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| 65 | |||
| 66 | /// Analysis pass providing a never-invalidated alias analysis result. |
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| 67 | class ObjCARCAA : public AnalysisInfoMixin<ObjCARCAA> { |
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| 68 | friend AnalysisInfoMixin<ObjCARCAA>; |
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| 69 | static AnalysisKey Key; |
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| 70 | |||
| 71 | public: |
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| 72 | typedef ObjCARCAAResult Result; |
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| 73 | |||
| 74 | ObjCARCAAResult run(Function &F, FunctionAnalysisManager &AM); |
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| 75 | }; |
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| 76 | |||
| 77 | } // namespace objcarc |
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| 78 | } // namespace llvm |
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| 79 | |||
| 80 | #endif |