[PATCH] D141439: [AARCH64][SME] Do not optimize vector conversions

Wed Jan 11 00:34:10 PST 2023

SjoerdMeijer added a comment.

Hi Zino,

Looks like the test case is failing? See https://reviews.llvm.org/harbormaster/unit/view/5711271/

I am wondering how big of a hammer this is. Are there no cases at all where doing this is beneficial?

Is the test case minimal? Think I see a loop, which we don't need? To see the codegen differences, it would be good if we can precommit a test, but then we want it more minimal if that is possible.

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Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:14232
+  // shuffle_vector instructions are serialized when targeting SVE,
+  // see https://reviews.llvm.org/D139111. This peephole is not beneficial.
+  if (Subtarget->useSVEForFixedLengthVectors())
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Nit: I would prefer a pointer to source-code (e.g. a function name) rather than a hyperlink, or just omit it if it is obvious.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D141439/new/

https://reviews.llvm.org/D141439