llvm-project/llvm/lib/Support/Annotation.cpp

131 lines
4.1 KiB
C++

//===-- Annotation.cpp - Implement the Annotation Classes -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the AnnotationManager class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Annotation.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/System/RWMutex.h"
#include <map>
#include <cstring>
using namespace llvm;
Annotation::~Annotation() {} // Designed to be subclassed
Annotable::~Annotable() { // Virtual because it's designed to be subclassed...
Annotation *A = AnnotationList;
while (A) {
Annotation *Next = A->getNext();
delete A;
A = Next;
}
}
namespace {
class StrCmp {
public:
bool operator()(const char *a, const char *b) const {
return strcmp(a, b) < 0;
}
};
}
typedef std::map<const char*, unsigned, StrCmp> IDMapType;
static volatile sys::cas_flag IDCounter = 0; // Unique ID counter
// Static member to ensure initialiation on demand.
static ManagedStatic<IDMapType> IDMap;
static ManagedStatic<sys::SmartRWMutex<true> > AnnotationsLock;
// On demand annotation creation support...
typedef Annotation *(*AnnFactory)(AnnotationID, const Annotable *, void *);
typedef std::map<unsigned, std::pair<AnnFactory,void*> > FactMapType;
static ManagedStatic<FactMapType> TheFactMap;
static FactMapType &getFactMap() {
return *TheFactMap;
}
static void eraseFromFactMap(unsigned ID) {
sys::SmartScopedWriter<true> Writer(*AnnotationsLock);
TheFactMap->erase(ID);
}
AnnotationID AnnotationManager::getID(const char *Name) { // Name -> ID
AnnotationsLock->reader_acquire();
IDMapType::iterator I = IDMap->find(Name);
IDMapType::iterator E = IDMap->end();
AnnotationsLock->reader_release();
if (I == E) {
sys::SmartScopedWriter<true> Writer(*AnnotationsLock);
I = IDMap->find(Name);
if (I == IDMap->end()) {
unsigned newCount = sys::AtomicIncrement(&IDCounter);
(*IDMap)[Name] = newCount-1; // Add a new element
return AnnotationID(newCount-1);
} else
return AnnotationID(I->second);
}
return AnnotationID(I->second);
}
// getID - Name -> ID + registration of a factory function for demand driven
// annotation support.
AnnotationID AnnotationManager::getID(const char *Name, Factory Fact,
void *Data) {
AnnotationID Result(getID(Name));
registerAnnotationFactory(Result, Fact, Data);
return Result;
}
// getName - This function is especially slow, but that's okay because it should
// only be used for debugging.
//
const char *AnnotationManager::getName(AnnotationID ID) { // ID -> Name
sys::SmartScopedReader<true> Reader(*AnnotationsLock);
IDMapType &TheMap = *IDMap;
for (IDMapType::iterator I = TheMap.begin(); ; ++I) {
assert(I != TheMap.end() && "Annotation ID is unknown!");
if (I->second == ID.ID) return I->first;
}
}
// registerAnnotationFactory - This method is used to register a callback
// function used to create an annotation on demand if it is needed by the
// Annotable::findOrCreateAnnotation method.
//
void AnnotationManager::registerAnnotationFactory(AnnotationID ID, AnnFactory F,
void *ExtraData) {
if (F) {
sys::SmartScopedWriter<true> Writer(*AnnotationsLock);
getFactMap()[ID.ID] = std::make_pair(F, ExtraData);
} else {
eraseFromFactMap(ID.ID);
}
}
// createAnnotation - Create an annotation of the specified ID for the
// specified object, using a register annotation creation function.
//
Annotation *AnnotationManager::createAnnotation(AnnotationID ID,
const Annotable *Obj) {
AnnotationsLock->reader_acquire();
FactMapType::iterator I = getFactMap().find(ID.ID);
if (I == getFactMap().end()) {
AnnotationsLock->reader_release();
return 0;
}
AnnotationsLock->reader_release();
return I->second.first(ID, Obj, I->second.second);
}