[PATCH] D127854: [InstCombine] Use known bits to determine exact int->fp cast

[Sanjay Patel via Phabricator via llvm-commits]

spatel accepted this revision.
spatel added a comment.
This revision is now accepted and ready to land.

LGTM - clearly, we can still do better, but this seems like a safe improvement.



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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp:1757
 
-  // TODO:
   // Try harder to find if the source integer type has less significant bits.
   // For example, compute number of sign bits or compute low bit mask.
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Please leave the TODO note. We could still check sign bits rather than zeros or do some other kind of refinement.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D127854/new/

https://reviews.llvm.org/D127854