[PATCH] D115863: [SVE][CodeGen] Use splice instruction when lowering VECTOR_SPLICE

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


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Comment at: llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h:455
 #include "AArch64GenSystemOperands.inc"
+  const unsigned invalid = 0xFFFFFFF;
 }
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Instead of making some arbitrary value 'invalid', maybe just return an `Optional<unsigned>` from `getSVEPredPatternFromNumElements` instead.
Because any value that's not between 0 and 31 inclusive, is invalid.

As an additional benefit, the result value of other uses of `getSVEPredPatternFromNumElements` in AArch64ISelLowering are checked validity too.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D115863/new/

https://reviews.llvm.org/D115863