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Missing FP optimization opportunities for fcmp ord operations #49175

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@aqjune

Description

@aqjune
Bugzilla Link 49831
Version trunk
OS All
Blocks #49274
CC @RKSimon,@rotateright

Extended Description

; Excerpted from llvm/test/Transforms/InstCombine/and-fcmp.ll

define i1 @_commute_logical(i1 %z, float %c, float %d) {
  %ord1 = fcmp ninf ord float %c, 0.0
  %and = select i1 %ord1, i1 %z, i1 false
  %ord2 = fcmp ninf reassoc ord float %d, 0.0
  %r = select i1 %ord2, i1 %and, i1 false
  ret i1 %r
}

This can be optimized to

  %c.fr = freeze float %c
  %ord1 = fcmp ord float %c.fr, %d
  %r = select i1 %ord1, i1 %z, i1 false

Alive2 link: https://alive2.llvm.org/ce/z/QfkJak

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