1//==- BlockCounter.h - ADT for counting block visits -------------*- 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//
10//  This file defines BlockCounter, an abstract data type used to count
11//  the number of times a given block has been visited along a path
12//  analyzed by CoreEngine.
13//
14//===----------------------------------------------------------------------===//
15
16#include "clang/StaticAnalyzer/Core/PathSensitive/BlockCounter.h"
17#include "llvm/ADT/ImmutableMap.h"
18
19using namespace clang;
20using namespace ento;
21
22namespace {
23
24class CountKey {
25  const StackFrameContext *CallSite;
26  unsigned BlockID;
27
28public:
29  CountKey(const StackFrameContext *CS, unsigned ID)
30    : CallSite(CS), BlockID(ID) {}
31
32  bool operator==(const CountKey &RHS) const {
33    return (CallSite == RHS.CallSite) && (BlockID == RHS.BlockID);
34  }
35
36  bool operator<(const CountKey &RHS) const {
37    return (CallSite == RHS.CallSite) ? (BlockID < RHS.BlockID)
38                                      : (CallSite < RHS.CallSite);
39  }
40
41  void Profile(llvm::FoldingSetNodeID &ID) const {
42    ID.AddPointer(CallSite);
43    ID.AddInteger(BlockID);
44  }
45};
46
47}
48
49typedef llvm::ImmutableMap<CountKey, unsigned> CountMap;
50
51static inline CountMap GetMap(void *D) {
52  return CountMap(static_cast<CountMap::TreeTy*>(D));
53}
54
55static inline CountMap::Factory& GetFactory(void *F) {
56  return *static_cast<CountMap::Factory*>(F);
57}
58
59unsigned BlockCounter::getNumVisited(const StackFrameContext *CallSite,
60                                       unsigned BlockID) const {
61  CountMap M = GetMap(Data);
62  CountMap::data_type* T = M.lookup(CountKey(CallSite, BlockID));
63  return T ? *T : 0;
64}
65
66BlockCounter::Factory::Factory(llvm::BumpPtrAllocator& Alloc) {
67  F = new CountMap::Factory(Alloc);
68}
69
70BlockCounter::Factory::~Factory() {
71  delete static_cast<CountMap::Factory*>(F);
72}
73
74BlockCounter
75BlockCounter::Factory::IncrementCount(BlockCounter BC,
76                                        const StackFrameContext *CallSite,
77                                        unsigned BlockID) {
78  return BlockCounter(GetFactory(F).add(GetMap(BC.Data),
79                                          CountKey(CallSite, BlockID),
80                             BC.getNumVisited(CallSite, BlockID)+1).getRoot());
81}
82
83BlockCounter
84BlockCounter::Factory::GetEmptyCounter() {
85  return BlockCounter(GetFactory(F).getEmptyMap().getRoot());
86}
87