Use WeakVH to hold dead mdnodes. Check use_empty() before deleting a node.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80928 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Devang Patel 2009-09-03 17:03:47 +00:00
parent dad45ea56e
commit 73b1ee857b

View File

@ -17,6 +17,7 @@
#include "llvm/Constants.h" #include "llvm/Constants.h"
#include "llvm/Instruction.h" #include "llvm/Instruction.h"
#include "llvm/Support/ManagedStatic.h" #include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/ValueHandle.h"
#include "LLVMContextImpl.h" #include "LLVMContextImpl.h"
#include <set> #include <set>
@ -45,24 +46,25 @@ GetElementPtrConstantExpr::GetElementPtrConstantExpr
} }
bool LLVMContext::RemoveDeadMetadata() { bool LLVMContext::RemoveDeadMetadata() {
std::vector<const MDNode *> DeadMDNodes; std::vector<WeakVH> DeadMDNodes;
bool Changed = false; bool Changed = false;
while (1) { while (1) {
for (FoldingSet<MDNode>::iterator for (FoldingSet<MDNode>::iterator
I = pImpl->MDNodeSet.begin(), I = pImpl->MDNodeSet.begin(),
E = pImpl->MDNodeSet.end(); I != E; ++I) { E = pImpl->MDNodeSet.end(); I != E; ++I) {
const MDNode *N = &(*I); MDNode *N = &(*I);
if (N->use_empty()) if (N->use_empty())
DeadMDNodes.push_back(N); DeadMDNodes.push_back(WeakVH(N));
} }
if (DeadMDNodes.empty()) if (DeadMDNodes.empty())
return Changed; return Changed;
while (!DeadMDNodes.empty()) { while (!DeadMDNodes.empty()) {
const MDNode *N = DeadMDNodes.back(); DeadMDNodes.pop_back(); const MDNode *N = cast<MDNode>(DeadMDNodes.back()); DeadMDNodes.pop_back();
delete N; if (N->use_empty())
delete N;
} }
} }
return Changed; return Changed;