[PATCH] D136015: [InstCombine] Fold series of instructions into mull

[Allen zhong via Phabricator via llvm-commits]

Allen added inline comments.


================
Comment at: llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp:1296
+      !match(YLo, m_And(m_Value(Y), m_SpecificInt(HalfMask))))
+    return nullptr;
+
----------------
RKSimon wrote:
> What about if the AND has been removed by SimplifyDemandedBits? Maybe also test for KnownBits known leading zeros?
Thanks for your suggestion, I'll record this issue, and I'll try out your suggestions later with a separate patch ?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D136015/new/

https://reviews.llvm.org/D136015