[PATCH] D120648: [RISCV] DAGcombine fold (bswap(srl (bswap c), x)) -> (shl c, x)

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

In D120648#3349296 <https://reviews.llvm.org/D120648#3349296>, @RKSimon wrote:

> TBH, this pattern is probably more likely to occur in general code than anything with a bitreverse

Fair enough, but in that case we need a different set of test cases. All of the examples here could legally be a single brev8(reverse bits within each byte) instruction. The shifts are artifacts of type legalization and shouldn't be there.


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