[PATCH] D64099: [InstCombine] pow(C,x) -> exp2(log2(C)*x)

[Dávid Bolvanský via Phabricator via llvm-commits]

xbolva00 added a comment.

GCC has exp variant of this transformation so I checked their preconditions - unsafe math. My first patch had isFast() check but @efriedma requested to specify it better. I think afn/ninf/nnan is all we need. I wrote some small tests and compared printed results between Clang and GCC. I don’t think we could formally prove this transformation with Alive.

So, If you can test this patch with SPEC, please do - Thanks!


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