[PATCH] D82910: [CodeGen][SVE] Don't drop scalable flag in DAGCombiner::visitEXTRACT_SUBVECTOR

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:19221
     unsigned SrcNumElts = SrcVT.getVectorNumElements();
     unsigned DestNumElts = V.getValueType().getVectorNumElements();
     if ((SrcNumElts % DestNumElts) == 0) {
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While we're here, do we need to change these getVectorNumElements() calls to getVectorElementCount()?


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:19238
       if ((NVT.getVectorNumElements() % DestSrcRatio) == 0) {
-        unsigned NewExtNumElts = NVT.getVectorNumElements() / DestSrcRatio;
+        ElementCount NewExtEC = NVT.getVectorElementCount() / DestSrcRatio;
         EVT ScalarVT = SrcVT.getScalarType();
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Does this math work correctly if we're extracting a fixed vector from a scalable vector?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D82910/new/

https://reviews.llvm.org/D82910