[all-commits] [llvm/llvm-project] b81c57: [ARM][LowOverheadLoops] Allow tail predication on ...

[Sam Tebbs via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: b81c57d646e49c15de1b6e2938b8689b7854a02b
      https://github.com/llvm/llvm-project/commit/b81c57d646e49c15de1b6e2938b8689b7854a02b
  Author: Sam Tebbs <samuel.tebbs at arm.com>
  Date:   2020-09-10 (Thu, 10 Sep 2020)

  Changed paths:
    M llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp
    A llvm/test/CodeGen/Thumb2/LowOverheadLoops/predicated-liveout-unknown-lanes.ll
    M llvm/test/CodeGen/Thumb2/mve-pred-vctpvpsel.ll

  Log Message:
  -----------
  [ARM][LowOverheadLoops] Allow tail predication on predicated instructions with unknown lane
values

The effects of unpredicated vector instruction with unknown
lanes cannot be predicted and therefore cannot be tail predicated. This
does not apply to predicated vector instructions and so this patch
allows tail predication on them.

Differential Revision: https://reviews.llvm.org/D87376