LLVM  6.0.0svn
CFLAndersAliasAnalysis.h
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1 //==- CFLAndersAliasAnalysis.h - Unification-based Alias Analysis -*- C++-*-==//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 /// \file
10 /// This is the interface for LLVM's inclusion-based alias analysis
11 /// implemented with CFL graph reachability.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_ANALYSIS_CFLANDERSALIASANALYSIS_H
16 #define LLVM_ANALYSIS_CFLANDERSALIASANALYSIS_H
17 
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/ADT/Optional.h"
22 #include "llvm/IR/PassManager.h"
23 #include "llvm/Pass.h"
24 #include <forward_list>
25 #include <memory>
26 
27 namespace llvm {
28 
29 class Function;
30 class MemoryLocation;
31 class TargetLibraryInfo;
32 
33 namespace cflaa {
34 
35 struct AliasSummary;
36 
37 } // end namespace cflaa
38 
39 class CFLAndersAAResult : public AAResultBase<CFLAndersAAResult> {
41 
42  class FunctionInfo;
43 
44 public:
45  explicit CFLAndersAAResult(const TargetLibraryInfo &TLI);
48 
49  /// Handle invalidation events from the new pass manager.
50  /// By definition, this result is stateless and so remains valid.
53  return false;
54  }
55 
56  /// Evict the given function from cache
57  void evict(const Function *Fn);
58 
59  /// \brief Get the alias summary for the given function
60  /// Return nullptr if the summary is not found or not available
61  const cflaa::AliasSummary *getAliasSummary(const Function &);
62 
63  AliasResult query(const MemoryLocation &, const MemoryLocation &);
64  AliasResult alias(const MemoryLocation &, const MemoryLocation &);
65 
66 private:
67  /// \brief Ensures that the given function is available in the cache.
68  /// Returns the appropriate entry from the cache.
69  const Optional<FunctionInfo> &ensureCached(const Function &);
70 
71  /// \brief Inserts the given Function into the cache.
72  void scan(const Function &);
73 
74  /// \brief Build summary for a given function
75  FunctionInfo buildInfoFrom(const Function &);
76 
77  const TargetLibraryInfo &TLI;
78 
79  /// \brief Cached mapping of Functions to their StratifiedSets.
80  /// If a function's sets are currently being built, it is marked
81  /// in the cache as an Optional without a value. This way, if we
82  /// have any kind of recursion, it is discernable from a function
83  /// that simply has empty sets.
85 
86  std::forward_list<cflaa::FunctionHandle<CFLAndersAAResult>> Handles;
87 };
88 
89 /// Analysis pass providing a never-invalidated alias analysis result.
90 ///
91 /// FIXME: We really should refactor CFL to use the analysis more heavily, and
92 /// in particular to leverage invalidation to trigger re-computation.
93 class CFLAndersAA : public AnalysisInfoMixin<CFLAndersAA> {
95 
96  static AnalysisKey Key;
97 
98 public:
100 
102 };
103 
104 /// Legacy wrapper pass to provide the CFLAndersAAResult object.
106  std::unique_ptr<CFLAndersAAResult> Result;
107 
108 public:
109  static char ID;
110 
112 
113  CFLAndersAAResult &getResult() { return *Result; }
114  const CFLAndersAAResult &getResult() const { return *Result; }
115 
116  void initializePass() override;
117  void getAnalysisUsage(AnalysisUsage &AU) const override;
118 };
119 
120 // createCFLAndersAAWrapperPass - This pass implements a set-based approach to
121 // alias analysis.
123 
124 } // end namespace llvm
125 
126 #endif // LLVM_ANALYSIS_CFLANDERSALIASANALYSIS_H
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
F(f)
A CRTP-driven "mixin" base class to help implement the function alias analysis results concept...
Key
PAL metadata keys.
AliasSummary is just a collection of ExternalRelation and ExternalAttribute.
const CFLAndersAAResult & getResult() const
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:153
A CRTP mix-in that provides informational APIs needed for analysis passes.
Definition: PassManager.h:382
Legacy wrapper pass to provide the CFLAndersAAResult object.
AliasResult
The possible results of an alias query.
Definition: AliasAnalysis.h:79
Represent the analysis usage information of a pass.
Analysis pass providing a never-invalidated alias analysis result.
Representation for a specific memory location.
ImmutablePass class - This class is used to provide information that does not need to be run...
Definition: Pass.h:256
Provides information about what library functions are available for the current target.
bool invalidate(Function &, const PreservedAnalyses &, FunctionAnalysisManager::Invalidator &)
Handle invalidation events from the new pass manager.
API to communicate dependencies between analyses during invalidation.
Definition: PassManager.h:559
A container for analyses that lazily runs them and caches their results.
ImmutablePass * createCFLAndersAAWrapperPass()
This header defines various interfaces for pass management in LLVM.
A special type used by analysis passes to provide an address that identifies that particular analysis...
Definition: PassManager.h:70
static Expected< BitVector > scan(StringRef &S, StringRef Original)
Definition: GlobPattern.cpp:67