lib/Support/Annotation.cpp

   1 //===-- Annotation.cpp - Implement the Annotation Classes -----------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file was developed by the LLVM research group and is distributed under
   6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the AnnotationManager class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Support/Annotation.h"
  15 #include <map>
  16 using namespace llvm;
  17
  18 Annotation::~Annotation() {}  // Designed to be subclassed
  19
  20 Annotable::~Annotable() {   // Virtual because it's designed to be subclassed...
  21   Annotation *A = AnnotationList;
  22   while (A) {
  23     Annotation *Next = A->getNext();
  24     delete A;
  25     A = Next;
  26   }
  27 }
  28
  29 typedef std::map<const std::string, unsigned> IDMapType;
  30 static unsigned IDCounter = 0;  // Unique ID counter
  31
  32 // Static member to ensure initialiation on demand.
  33 static IDMapType &getIDMap() { static IDMapType TheMap; return TheMap; }
  34
  35 // On demand annotation creation support...
  36 typedef Annotation *(*AnnFactory)(AnnotationID, const Annotable *, void *);
  37 typedef std::map<unsigned, std::pair<AnnFactory,void*> > FactMapType;
  38
  39 static FactMapType *TheFactMap = 0;
  40 static FactMapType &getFactMap() {
  41   if (TheFactMap == 0)
  42     TheFactMap = new FactMapType();
  43   return *TheFactMap;
  44 }
  45
  46 static void eraseFromFactMap(unsigned ID) {
  47   assert(TheFactMap && "No entries found!");
  48   TheFactMap->erase(ID);
  49   if (TheFactMap->empty()) {   // Delete when empty
  50     delete TheFactMap;
  51     TheFactMap = 0;
  52   }
  53 }
  54
  55 AnnotationID AnnotationManager::getID(const std::string &Name) {  // Name -> ID
  56   IDMapType::iterator I = getIDMap().find(Name);
  57   if (I == getIDMap().end()) {
  58     getIDMap()[Name] = IDCounter++;   // Add a new element
  59     return IDCounter-1;
  60   }
  61   return I->second;
  62 }
  63
  64 // getID - Name -> ID + registration of a factory function for demand driven
  65 // annotation support.
  66 AnnotationID AnnotationManager::getID(const std::string &Name, Factory Fact,
  67                                       void *Data) {
  68   AnnotationID Result(getID(Name));
  69   registerAnnotationFactory(Result, Fact, Data);
  70   return Result;
  71 }
  72
  73 // getName - This function is especially slow, but that's okay because it should
  74 // only be used for debugging.
  75 //
  76 const std::string &AnnotationManager::getName(AnnotationID ID) {  // ID -> Name
  77   IDMapType &TheMap = getIDMap();
  78   for (IDMapType::iterator I = TheMap.begin(); ; ++I) {
  79     assert(I != TheMap.end() && "Annotation ID is unknown!");
  80     if (I->second == ID.ID) return I->first;
  81   }
  82 }
  83
  84 // registerAnnotationFactory - This method is used to register a callback
  85 // function used to create an annotation on demand if it is needed by the
  86 // Annotable::findOrCreateAnnotation method.
  87 //
  88 void AnnotationManager::registerAnnotationFactory(AnnotationID ID, AnnFactory F,
  89                                                   void *ExtraData) {
  90   if (F)
  91     getFactMap()[ID.ID] = std::make_pair(F, ExtraData);
  92   else
  93     eraseFromFactMap(ID.ID);
  94 }
  95
  96 // createAnnotation - Create an annotation of the specified ID for the
  97 // specified object, using a register annotation creation function.
  98 //
  99 Annotation *AnnotationManager::createAnnotation(AnnotationID ID,
 100                                                 const Annotable *Obj) {
 101   FactMapType::iterator I = getFactMap().find(ID.ID);
 102   if (I == getFactMap().end()) return 0;
 103   return I->second.first(ID, Obj, I->second.second);
 104 }