[PATCH] D98564: [AArch64] Peephole rule to remove redundant cmp after cset.

[Pavel Iliin via Phabricator via llvm-commits]

ilinpv created this revision.
ilinpv added reviewers: dmgreen, SjoerdMeijer, paquette.
Herald added subscribers: danielkiss, hiraditya, kristof.beyls.
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Comparisons to zero or one after cset instructions can be safely
removed in examples like:

cset w9, eq          cset w9, eq
cmp  w9, #1   --->   <removed>
b.ne    .L1 <https://reviews.llvm.org/L1>          b.ne    .L1 <https://reviews.llvm.org/L1>

cset w9, eq          cset w9, eq
cmp  w9, #0   --->   <removed>
b.ne    .L1 <https://reviews.llvm.org/L1>          b.eq    .L1 <https://reviews.llvm.org/L1>

Peephole optimization to detect suitable cases and get rid of that
comparisons added.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D98564

Files:
  llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
  llvm/lib/Target/AArch64/AArch64InstrInfo.h
  llvm/test/CodeGen/AArch64/csinc-cmp-removal.mir
  llvm/test/CodeGen/AArch64/f16-instructions.ll

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