[all-commits] [llvm/llvm-project] d43d9e: [FPEnv][InstSimplify] Fold fsub -0.0, -X ==> X

[Kevin P. Neal via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d43d9e1d5c98e64db1054b4fb91d044299d3f717
      https://github.com/llvm/llvm-project/commit/d43d9e1d5c98e64db1054b4fb91d044299d3f717
  Author: Kevin P. Neal <kevin.neal at sas.com>
  Date:   2022-04-14 (Thu, 14 Apr 2022)

  Changed paths:
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/test/Transforms/InstSimplify/strictfp-fsub.ll

  Log Message:
  -----------
  [FPEnv][InstSimplify] Fold fsub -0.0, -X ==> X

Currently the fsub optimizations in InstSimplify don't know how to fold
-0.0 - (-X) to X when the constrained intrinsics are used. This adds partial
support. The rest of the support will come later with work on the IR
matchers.

This review is split out from D107285.

Differential Revision: https://reviews.llvm.org/D123396