InstCombine: Turn _chk functions into the "unsafe" variant if length and max langth are equal.
This happens when we take the (non-constant) length from a malloc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122961 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 603a010..ecd2243 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -722,6 +722,8 @@
NewInstruction = IC->ReplaceInstUsesWith(*CI, With);
}
bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
+ if (CI->getArgOperand(SizeCIOp) == CI->getArgOperand(SizeArgOp))
+ return true;
if (ConstantInt *SizeCI =
dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) {
if (SizeCI->isAllOnesValue())