[all-commits] [llvm/llvm-project] c19c15: AMDGPU: Don't ignore carry out user when expanding...

[Matt Arsenault via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: c19c153e7415807f043edc42843bc491232b717e
      https://github.com/llvm/llvm-project/commit/c19c153e7415807f043edc42843bc491232b717e
  Author: Matt Arsenault <Matthew.Arsenault at amd.com>
  Date:   2020-07-06 (Mon, 06 Jul 2020)

  Changed paths:
    M llvm/lib/Target/AMDGPU/SIISelLowering.cpp
    A llvm/test/CodeGen/AMDGPU/expand-scalar-carry-out-select-user.ll

  Log Message:
  -----------
  AMDGPU: Don't ignore carry out user when expanding add_co_pseudo

This was resulting in a missing vreg def in the use select
instruction.

The output of the pseudo doesn't make sense, since it really shouldn't
have the vreg output in the first place, and instead an implicit scc
def to match the real scalar behavior.

We could have easier to understand tests if we selected scalar
versions of the [us]{add|sub}.with.overflow intrinsics.

This does still end up producing vector code in the end, since it gets
moved later.