Clean up reference counting to stop "leaking" alias sets

llvm-svn: 15099
This commit is contained in:
Chris Lattner 2004-07-22 07:58:18 +00:00
parent f2b976bdd5
commit 053427ff4f
2 changed files with 27 additions and 25 deletions

View File

@ -62,9 +62,8 @@ class AliasSet {
if (AS->Forward) {
AliasSet *OldAS = AS;
AS = OldAS->getForwardedTarget(AST);
if (--OldAS->RefCount == 0)
OldAS->removeFromTracker(AST);
AS->RefCount++;
AS->addRef();
OldAS->dropRef(AST);
}
return AS;
}
@ -118,6 +117,13 @@ class AliasSet {
void setPrev(AliasSet *P) { Prev = P; }
void setNext(AliasSet *N) { Next = N; }
void addRef() { ++RefCount; }
void dropRef(AliasSetTracker &AST) {
assert(RefCount >= 1 && "Invalid reference count detected!");
if (--RefCount == 0)
removeFromTracker(AST);
}
public:
/// Accessors...
bool isRef() const { return AccessTy & Refs; }
@ -187,15 +193,10 @@ private:
AliasSet() : PtrList(0), PtrListEnd(&PtrList), Forward(0), RefCount(0),
AccessTy(NoModRef), AliasTy(MustAlias), Volatile(false) {
}
AliasSet(const AliasSet &AS) {
// AliasSet's only get copy constructed in simple circumstances. In
// particular, they cannot have any pointers in their list. Despite this,
// we have to be sure to update the PtrListEnd to not point to the source
// AliasSet's list.
assert(AS.PtrList == 0 && "AliasSet has pointers in it!");
PtrList = 0; PtrListEnd = &PtrList;
Forward = AS.Forward; RefCount = AS.RefCount;
AccessTy = AS.AccessTy; AliasTy = AS.AliasTy; Volatile = AS.Volatile;
assert(0 && "Copy ctor called!?!?!");
abort();
}
HashNodePair *getSomePointer() const {
@ -210,9 +211,8 @@ private:
AliasSet *Dest = Forward->getForwardedTarget(AST);
if (Dest != Forward) {
Dest->RefCount++;
if (--Forward->RefCount == 0)
Forward->removeFromTracker(AST);
Dest->addRef();
Forward->dropRef(AST);
Forward = Dest;
}
return Dest;

View File

@ -45,7 +45,7 @@ void AliasSet::mergeSetIn(AliasSet &AS) {
assert(RefCount != 0);
AS.Forward = this; // Forward across AS now...
RefCount++; // AS is now pointing to us...
addRef(); // AS is now pointing to us...
// Merge the list of constituent pointers...
if (AS.PtrList) {
@ -59,6 +59,10 @@ void AliasSet::mergeSetIn(AliasSet &AS) {
}
void AliasSetTracker::removeAliasSet(AliasSet *AS) {
if (AliasSet *Fwd = AS->Forward) {
Fwd->dropRef(*this);
AS->Forward = 0;
}
AliasSets.erase(AS);
}
@ -91,7 +95,7 @@ void AliasSet::addPointer(AliasSetTracker &AST, HashNodePair &Entry,
assert(*PtrListEnd == 0 && "End of list is not null?");
*PtrListEnd = &Entry;
PtrListEnd = Entry.second.setPrevInList(PtrListEnd);
RefCount++; // Entry points to alias set...
addRef(); // Entry points to alias set...
}
void AliasSet::addCallSite(CallSite CS, AliasAnalysis &AA) {
@ -130,7 +134,7 @@ bool AliasSet::aliasesPointer(const Value *Ptr, unsigned Size,
// If this is a may-alias set, we have to check all of the pointers in the set
// to be sure it doesn't alias the set...
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.alias(Ptr, Size, I->first, I->second.getSize()))
if (AA.alias(Ptr, Size, I.getPointer(), I.getSize()))
return true;
// Check the call sites list and invoke list...
@ -204,7 +208,7 @@ AliasSet &AliasSetTracker::getAliasSetForPointer(Value *Pointer, unsigned Size,
} else {
if (New) *New = true;
// Otherwise create a new alias set to hold the loaded pointer...
AliasSets.push_back(AliasSet());
AliasSets.push_back(new AliasSet());
AliasSets.back().addPointer(*this, Entry, Size);
return AliasSets.back();
}
@ -238,7 +242,7 @@ bool AliasSetTracker::add(CallSite CS) {
AliasSet *AS = findAliasSetForCallSite(CS);
if (!AS) {
AliasSets.push_back(AliasSet());
AliasSets.push_back(new AliasSet());
AS = &AliasSets.back();
AS->addCallSite(CS, AA);
return true;
@ -285,7 +289,7 @@ void AliasSetTracker::add(const AliasSetTracker &AST) {
AliasSet::iterator I = AS.begin(), E = AS.end();
bool X;
for (; I != E; ++I)
addPointer(I->first, I->second.getSize(),
addPointer(I.getPointer(), I.getSize(),
(AliasSet::AccessType)AS.AccessTy, X);
}
}
@ -364,9 +368,7 @@ void AliasSetTracker::deleteValue(Value *PtrVal) {
// Unlink from the list of values...
PtrValEnt.second.removeFromList();
// Stop using the alias set
if (--AS->RefCount == 0)
AS->removeFromTracker(*this);
AS->dropRef(*this);
PointerMap.erase(I);
}
@ -394,8 +396,8 @@ void AliasSet::print(std::ostream &OS) const {
OS << "Pointers: ";
for (iterator I = begin(), E = end(); I != E; ++I) {
if (I != begin()) OS << ", ";
WriteAsOperand(OS << "(", I->first);
OS << ", " << I->second.getSize() << ")";
WriteAsOperand(OS << "(", I.getPointer());
OS << ", " << I.getSize() << ")";
}
}
if (!CallSites.empty()) {