[all-commits] [llvm/llvm-project] d3bf06: [DAGCombiner] Add combine for (not (strict_fsetcc)...

[topperc via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: d3bf06bc81e38202ab2684b17f6bdb23784173d7
      https://github.com/llvm/llvm-project/commit/d3bf06bc81e38202ab2684b17f6bdb23784173d7
  Author: Craig Topper <craig.topper at intel.com>
  Date:   2020-01-24 (Fri, 24 Jan 2020)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    M llvm/test/CodeGen/X86/fp-strict-scalar-cmp.ll

  Log Message:
  -----------
  [DAGCombiner] Add combine for (not (strict_fsetcc)) to create a strict_fsetcc with the opposite condition.

Unlike the existing code that I modified here, I only handle the
case where the strict_fsetcc has a single use. Not sure exactly
how to handle multiples uses.

Testing this on X86 is hard because we already have a other
combines that get rid of lowered version of the integer setcc that
this xor will eventually become. So this combine really just
saves a bunch of extra nodes being created. Not sure about other
targets.

Differential Revision: https://reviews.llvm.org/D71816