[PATCH] D123626: [InstCombine] Fold memrchr calls with constant size of zero or one.

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp:873
+  Value *Size = CI->getArgOperand(2);
+  annotateNonNullAndDereferenceable(CI, 0, Size, DL);
+  Value *CharVal = CI->getArgOperand(1);
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I'm not entirely sure this is correct. This is definitely incorrect for memchr() and I submitted D123665 to fix that. memrchr() is a GNU extension, so I'm not sure whether the same rules apply there. I guess one could argue that memrchr() should require a fully dereferenceable object, as otherwise the base pointer will already point outside the object.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D123626/new/

https://reviews.llvm.org/D123626