[all-commits] [llvm/llvm-project] 18db29: [PowerPC] Add peephole to remove redundant accumul...

[bsaleil via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 18db29ea6fb6231221da412dbf07c186401bc496
      https://github.com/llvm/llvm-project/commit/18db29ea6fb6231221da412dbf07c186401bc496
  Author: Baptiste Saleil <baptiste.saleil at ibm.com>
  Date:   2020-11-18 (Wed, 18 Nov 2020)

  Changed paths:
    M llvm/lib/Target/PowerPC/PPCPreEmitPeephole.cpp
    M llvm/test/CodeGen/PowerPC/mma-acc-memops.ll
    M llvm/test/CodeGen/PowerPC/mma-intrinsics.ll

  Log Message:
  -----------
  [PowerPC] Add peephole to remove redundant accumulator prime/unprime instructions

In some situations, the compiler may insert an accumulator prime instruction and
an accumulator unprime instruction with no use of that accumulator between the two.
That's for example the case when we store an accumulator after assembling it or
restoring it. This patch adds a peephole to remove these prime and unprime instructions.

Differential Revision: https://reviews.llvm.org/D91386