tree 3013e32176fb092e8c6ba096db1ac1db607c9aba
parent 028a4de6c67e03d463e0e796cdc9c5a53374f665
author David Green <david.green@arm.com> 1638040036 +0000
committer Copybara-Service <copybara-worker@google.com> 1638040411 -0800

[ARM] Fold away unnecessary CSET/CMPZ

Codegen from expanded vector operations can end up with unnecessary
CMPZ/CSINC, of the form:
  CSXYZ A, B, C1 (CMPZ (CSINC 0, 0, C2, D), 0)

These can be converted to remove the CMPZ and CSINC, depending on the
condition.
  if C1==NE -> CSXYZ A, B, C2, D
  if C1==EQ -> CSXYZ A, B, NOT(C2), D

Differential Revision: https://reviews.llvm.org/D114013

GitOrigin-RevId: 7d5d063c7745672afaab9dc2e744d43093fa6062