[PATCH] D74228: [PatternMatch] Match XOR variant of unsigned-add overflow check.

[Florian Hahn via Phabricator via llvm-commits]

fhahn marked an inline comment as done.
fhahn added inline comments.


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Comment at: llvm/include/llvm/IR/PatternMatch.h:1712
+      Value *Op1;
+      if (m_OneUse(m_Xor(m_Value(Op1), m_AllOnes())).match(ICmpLHS))
+        return L.match(Op1) && R.match(ICmpRHS) && S.match(ICmpLHS);
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lebedev.ri wrote:
> Hm, i don't really see one-use checks in similar neighboring patterns here.
I can drop it here, but I think we should be more restrictive here, because we cannot use the math result for the xor. Alternatively we can have the use check in CGP.


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  https://reviews.llvm.org/D74228/new/

https://reviews.llvm.org/D74228