[PATCH] D125774: [InstCombine] fold float trunc into exact itofp for small constants

[Allen zhong via Phabricator via llvm-commits]

Allen added a comment.

In D125774#3520161 <https://reviews.llvm.org/D125774#3520161>, @efriedma wrote:

> Specifically detecting this exact case doesn't really seem very useful... we should be leveraging some sort of range analysis (known bits, CorrelatedValuePropagation, etc.)

Thanks @efriedma very much, I updated with computeKnownBits according your idea.


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https://reviews.llvm.org/D125774