lib/GR/GRBlockCounter.cpp

   1 //==- GRBlockCounter.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 GRBlockCounter, an abstract data type used to count
  11 //  the number of times a given block has been visited along a path
  12 //  analyzed by GRCoreEngine.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "clang/GR/PathSensitive/GRBlockCounter.h"
  17 #include "llvm/ADT/ImmutableMap.h"
  18
  19 using namespace clang;
  20 using namespace GR;
  21
  22 namespace {
  23
  24 class CountKey {
  25   const StackFrameContext *CallSite;
  26   unsigned BlockID;
  27
  28 public:
  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
  49 typedef llvm::ImmutableMap<CountKey, unsigned> CountMap;
  50
  51 static inline CountMap GetMap(void* D) {
  52   return CountMap(static_cast<CountMap::TreeTy*>(D));
  53 }
  54
  55 static inline CountMap::Factory& GetFactory(void* F) {
  56   return *static_cast<CountMap::Factory*>(F);
  57 }
  58
  59 unsigned GRBlockCounter::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
  66 GRBlockCounter::Factory::Factory(llvm::BumpPtrAllocator& Alloc) {
  67   F = new CountMap::Factory(Alloc);
  68 }
  69
  70 GRBlockCounter::Factory::~Factory() {
  71   delete static_cast<CountMap::Factory*>(F);
  72 }
  73
  74 GRBlockCounter
  75 GRBlockCounter::Factory::IncrementCount(GRBlockCounter BC,
  76                                         const StackFrameContext *CallSite,
  77                                         unsigned BlockID) {
  78   return GRBlockCounter(GetFactory(F).add(GetMap(BC.Data),
  79                                           CountKey(CallSite, BlockID),
  80                              BC.getNumVisited(CallSite, BlockID)+1).getRoot());
  81 }
  82
  83 GRBlockCounter
  84 GRBlockCounter::Factory::GetEmptyCounter() {
  85   return GRBlockCounter(GetFactory(F).getEmptyMap().getRoot());
  86 }