[PATCH] D37989: InstCombine: Insert missing canonicalizes

[escha via Phabricator via llvm-commits]

escha added a comment.

In https://reviews.llvm.org/D37989#936337, @scanon wrote:

> IEEE 754 rules are that everything canonicalizes except bitwise operations (copy, abs, negate, copysign) and decimal re-encoding operations (which you don't care about).


Does this mean that we need to make all other float optimizations in LLVM do the same?

for example, we cannot optimize fmul(x, 1) to x, we must optimize it to fcanonicalize(x), right? thus preventing pretty much all float optimizations, since presumably that will act as a barrier.


https://reviews.llvm.org/D37989