[PATCH] D131378: [LoongArch] Add codegen support for bitreverse

[Lu Weining via Phabricator via llvm-commits]

SixWeining added inline comments.


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Comment at: llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp:77
+  setOperationAction(ISD::BITREVERSE, MVT::i8, Custom);
+  setOperationAction(ISD::BITREVERSE, MVT::i16, Custom);
+  if (Subtarget.is64Bit()) {
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How about leave it to legal and use bitrev.4b+srli.w/d. I'm not sure which is fast and better.


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Comment at: llvm/test/CodeGen/LoongArch/bitreverse.ll:2
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=loongarch32 --verify-machineinstrs < %s \
+; RUN:   | FileCheck %s --check-prefix=LA32
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Nit: had better use `--`.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D131378/new/

https://reviews.llvm.org/D131378