Under a compiler flag, -freset-local-blocks,
wipe out stack blocks when they go out of scope.
// rdar://9227352
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@134045 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp
index a0a8d66..20b5c9b 100644
--- a/lib/CodeGen/CGBlocks.cpp
+++ b/lib/CodeGen/CGBlocks.cpp
@@ -25,6 +25,22 @@
using namespace clang;
using namespace CodeGen;
+struct CallMemsetLocalBlockObject : EHScopeStack::Cleanup {
+ llvm::AllocaInst *BlockAddr;
+ CharUnits BlockSize;
+
+ CallMemsetLocalBlockObject(llvm::AllocaInst *blockAddr,
+ CharUnits blocSize)
+ : BlockAddr(blockAddr), BlockSize(blocSize) {}
+
+ void Emit(CodeGenFunction &CGF, bool isForEH) {
+ CGF.Builder.CreateMemSet(BlockAddr,
+ llvm::ConstantInt::get(CGF.Int8Ty, 0xCD),
+ BlockSize.getQuantity(),
+ BlockAddr->getAlignment());
+ }
+};
+
CGBlockInfo::CGBlockInfo(const BlockExpr *blockExpr, const char *N)
: Name(N), CXXThisIndex(0), CanBeGlobal(false), NeedsCopyDispose(false),
HasCXXObject(false), UsesStret(false), StructureType(0), Block(blockExpr) {
@@ -649,6 +665,9 @@
llvm::Value *result =
Builder.CreateBitCast(blockAddr,
ConvertType(blockInfo.getBlockExpr()->getType()));
+ if (getLangOptions().ResetLocalBlocks)
+ EHStack.pushCleanup<CallMemsetLocalBlockObject>(NormalCleanup, blockAddr,
+ blockInfo.BlockSize);
return result;
}