[all-commits] [llvm/llvm-project] 300997: [AArch64] Don't rename registers with pseudo defs ...

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 300997c41a00b705ca10264c15910dd8d691ab75
      https://github.com/llvm/llvm-project/commit/300997c41a00b705ca10264c15910dd8d691ab75
  Author: Florian Hahn <florian_hahn at apple.com>
  Date:   2020-01-22 (Wed, 22 Jan 2020)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp
    M llvm/test/CodeGen/AArch64/stp-opt-with-renaming.mir

  Log Message:
  -----------
  [AArch64] Don't rename registers with pseudo defs in Ld/St opt.

If the root def of for renaming is a noop-pseudo instruction like kill,
we would end up without a correct def for the renamed register, causing
miscompiles.

This patch conservatively bails out on any pseudo instruction.

This fixes https://bugs.chromium.org/p/chromium/issues/detail?id=1037912#c70