[all-commits] [llvm/llvm-project] decbd2: Reapply "InstCombine: Introduce SimplifyDemandedUs...

[Matt Arsenault via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: decbd29f9e9be50756a083cd677f7fea22cd3c91
      https://github.com/llvm/llvm-project/commit/decbd29f9e9be50756a083cd677f7fea22cd3c91
  Author: Matt Arsenault <Matthew.Arsenault at amd.com>
  Date:   2024-02-08 (Thu, 08 Feb 2024)

  Changed paths:
    M llvm/include/llvm/Analysis/ValueTracking.h
    M llvm/lib/Transforms/InstCombine/InstCombineInternal.h
    M llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
    M llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
    M llvm/test/Transforms/InstCombine/simplify-demanded-fpclass.ll

  Log Message:
  -----------
  Reapply "InstCombine: Introduce SimplifyDemandedUseFPClass"" (#74056)

This reverts commit ef388334ee5a3584255b9ef5b3fefdb244fa3fd7.

The referenced issue violates the spec for finite-only math only by
using a return value for a constant infinity. If the interpretation
is results and arguments cannot violate nofpclass, then any
std::numeric_limits<T>::infinity() result is invalid under
-ffinite-math-only. Without this interpretation the utility of
nofpclass is slashed.