[PATCH] D156449: [LLVM][Transforms]

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

Please upload with full context. It's impossible to review most of these changes in the web view otherwise.



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Comment at: llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp:413
+    auto *ZExtInst = CastInst::Create(Instruction::ZExt, And, Ty);
+    ZExtInst->setWasSext(true);
+    return ZExtInst;
----------------
I don't think this is correct.

`was_sext` is supposed to indicate that the sign bit of the input to the zext is known to be 0. Making the zext and sext equivalent. In this case the input is only a single bit, making the input only a sign bit. It is not known to be 0.


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D156449/new/

https://reviews.llvm.org/D156449