[all-commits] [llvm/llvm-project] 966435: [AArch64] Fold CSEL x, x, cc -> x

[David Green via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 966435daf96913d50130ea821675fd31a27c1a13
      https://github.com/llvm/llvm-project/commit/966435daf96913d50130ea821675fd31a27c1a13
  Author: David Green <david.green at arm.com>
  Date:   2021-05-03 (Mon, 03 May 2021)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/lib/Target/AArch64/AArch64ISelLowering.h
    M llvm/test/CodeGen/AArch64/srem-seteq.ll

  Log Message:
  -----------
  [AArch64] Fold CSEL x, x, cc -> x

This can come up in rare situations, where a csel is created with
identical operands. These can be folded simply to the original value,
allowing the csel to be removed and further simplification to happen.

This patch also removes FCSEL as it is unused, not being produced
anywhere or lowered to anything.

Differential Revision: https://reviews.llvm.org/D101687