[PATCH] D29344: [AArch64] Extend redundant copy elimination pass to handle non-zero stores.

[Chad Rosier via Phabricator via llvm-commits]

mcrosier created this revision.
Herald added subscribers: rengolin, aemerson.

This patch extends the current functionality of the AArch64 redundant copy elimination pass to handle non-zero cases such as:

  BB#0:
    cmp x0, #1
    b.eq .LBB0_1
  .LBB0_1:
    orr x0, xzr, #0x1  ; <-- redundant copy; x0 known to hold #1.

This removes redundant copies from most of the SPEC200X tests.  When running on Kryo, I saw a 2.7% and 1% improvement in spec2000/gap and spec2006/povray, respectively.  All other testing was within noise.

Chad


https://reviews.llvm.org/D29344

Files:
  lib/Target/AArch64/AArch64RedundantCopyElimination.cpp
  test/CodeGen/AArch64/machine-copy-remove.mir

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