[PATCH] D118012: [DAGCombiner][RISCV] Canonicalize (bswap(bitreverse(x))->bitreverse(bswap(x)).

[Craig Topper via Phabricator via llvm-commits]

craig.topper created this revision.
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If the bitreverse gets expanded, it will introduce a new bswap. By
putting a bswap before the bitreverse, we can ensure it gets cancelled
out when this happens.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D118012

Files:
  llvm/test/CodeGen/RISCV/bswap-bitreverse-ctlz-cttz-ctpop.ll
  llvm/test/CodeGen/RISCV/rv32zbp.ll
  llvm/test/CodeGen/RISCV/rv64zbp.ll

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