[all-commits] [llvm/llvm-project] 8fbc14: [AArch64] Merge [US]MULL with half adds and subs i...

[Andre Vieira via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 8fbc1437c605fe92c0fa286757e3b287d6b02f05
      https://github.com/llvm/llvm-project/commit/8fbc1437c605fe92c0fa286757e3b287d6b02f05
  Author: Andre Vieira <andre.simoesdiasvieira at arm.com>
  Date:   2021-01-25 (Mon, 25 Jan 2021)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64InstrInfo.td
    A llvm/test/CodeGen/AArch64/mla_mls_merge.ll

  Log Message:
  -----------
  [AArch64] Merge [US]MULL with half adds and subs into [US]ML[AS]L

This patch adds patterns to teach the AArch64 backend to merge [US]MULL
instructions and adds/subs of half the size into [US]ML[AS]L where we don't use
the top half of the result.

Differential Revision: https://reviews.llvm.org/D95218