[all-commits] [llvm/llvm-project] 21f1b2: [InstSimplify] fold fsub nnan with Inf operand

[Sanjay Patel via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 21f1b2da95a32307d42128d9fb446c57f0fb8ee9
      https://github.com/llvm/llvm-project/commit/21f1b2da95a32307d42128d9fb446c57f0fb8ee9
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2022-11-11 (Fri, 11 Nov 2022)

  Changed paths:
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/test/Transforms/InstSimplify/floating-point-arithmetic.ll
    M llvm/test/Transforms/InstSimplify/fp-undef-poison.ll

  Log Message:
  -----------
  [InstSimplify] fold fsub nnan with Inf operand

Similar to fbc2c8f2fbbb, but if we have a non-canonical
fsub with constant operand 1, then flip the sign of the
Infinity:
https://alive2.llvm.org/ce/z/vKWfhW

If Infinity is operand 0, then the sign remains:
https://alive2.llvm.org/ce/z/73d97C