[PATCH] D80437: [CodeGen] Let computeKnownBits do something sensible for scalable vectors

[David Sherwood via Phabricator via llvm-commits]

david-arm marked an inline comment as done.
david-arm added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:2253
+  APInt DemandedElts;
+  if (!VT.isScalableVector()) {
+    DemandedElts = VT.isVector()
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efriedma wrote:
> If we're going to bail out anyway, can we bail out explicitly, instead of waiting for computeKnownBits to bail out?
I thought about that, but then I was also worried about duplicating the behaviour of the called routines in the callers. If the behaviour of MaskedValueIsZero or computeKnownBits changes, i.e. how we return values and so on, then this becomes out of sync. If you don't think that's a problem I can bail out early as you suggested?


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https://reviews.llvm.org/D80437