[PATCH] D102828: [GlobalISel] Implement splitting of G_SHUFFLE_VECTOR.

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:4231
+  // Further legalization attempts will be needed to do split further.
+  NarrowTy = DstTy.changeNumElements(DstTy.getNumElements() / 2);
+  unsigned NewElts = NarrowTy.getNumElements();
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aemerson wrote:
> arsenm wrote:
> > I don't like simply discarding NarrowTy. It would be better to compute the type you do handle, and fail if it doesn't match the requested type
> But if you do that, fewerElements isn't going to know which narrow type it supports. Legalizing <16 x s64> is going to use a narrow ty of <2 x s64> with the rules as they're written now.
I don't follow, the parameter tells you which type to use


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102828/new/

https://reviews.llvm.org/D102828