[PATCH] D154953: [InstSimplify] Remove the remainder loop if we know the mask is always true

[Nikita Popov via Phabricator via llvm-commits]

nikic added a comment.

Please add an alive2 proof to the patch description.



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Comment at: llvm/lib/Analysis/InstructionSimplify.cpp:1286
+      unsigned MaxActiveBits = Known.countMaxActiveBits();
+      if (MaxActiveBits <= RemC->logBase2())
+        return ConstantInt::getNullValue(Op0->getType());
----------------
This check looks a bit roundabout. I think what you actually want to check is that `Known.getMaxValue().ule(*RemC)`?


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  https://reviews.llvm.org/D154953/new/

https://reviews.llvm.org/D154953