6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-08-21 18:29:46 +00:00
Code Issues Projects Releases Wiki Activity

Switch DIDescriptor to use a TrackingVH. - This makes it much safer to work with debug info, since it was extraordinarily easy to have dangling pointers thanks to MDNode uniquing.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82507 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Daniel Dunbar 2009-09-22 02:03:18 +00:00
parent e5b18362db
commit 48a097bfb6
2 changed files with 14 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
include/llvm/Analysis/DebugInfo.h
View File

@ -24,6 +24,7 @@
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ValueHandle.h"
namespace llvm {
class BasicBlock;
@ -45,7 +46,7 @@ namespace llvm {
class DIDescriptor {
protected:
MDNode *DbgNode;
TrackingVH<MDNode> DbgNode;
/// DIDescriptor constructor. If the specified node is non-null, check
/// to make sure that the tag in the descriptor matches 'RequiredTag'. If

15
lib/Analysis/DebugInfo.cpp
View File

@ -267,8 +267,17 @@ void DIDerivedType::replaceAllUsesWith(DIDescriptor &D) {
return;
assert (!D.isNull() && "Can not replace with null");
DbgNode->replaceAllUsesWith(D.getNode());
delete DbgNode;
// Since we use a TrackingVH for the node, its easy for clients to manufacture
// legitimate situations where they want to replaceAllUsesWith() on something
// which, due to uniquing, has merged with the source. We shield clients from
// this detail by allowing a value to be replaced with replaceAllUsesWith()
// itself.
if (getNode() != D.getNode()) {
MDNode *Node = DbgNode;
Node->replaceAllUsesWith(D.getNode());
delete Node;
}
}
/// Verify - Verify that a compile unit is well formed.
@ -395,7 +404,7 @@ bool DISubprogram::describes(const Function *F) {
/// dump - Print descriptor.
void DIDescriptor::dump() const {
errs() << "[" << dwarf::TagString(getTag()) << "] ";
errs().write_hex((intptr_t)DbgNode) << ']';
errs().write_hex((intptr_t) &*DbgNode) << ']';
}
/// dump - Print compile unit.