[PATCH] D97582: [LegalizeVectorTypes] Improve SplitVecRes_INSERT_SUBVECTOR to handle subvector being in the high half of the split or not at element 0 of the low half.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp:1265
+  // If we know the index is in the first half, and we know the subvector
+  // doesn't cross the/ boundary between the halves, we can avoid spilling the
+  // vector, and insert into the lower half of the split vector directly.
----------------
typo /


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Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp:1269
   unsigned IdxVal = cast<ConstantSDNode>(Idx)->getZExtValue();
-  if ((IdxVal == 0) && (IdxVal + SubElems <= VecElems / 2)) {
+  if (IdxVal >= 0 && (IdxVal + SubElems <= VecElems / 2)) {
     EVT LoVT, HiVT;
----------------
Should we be using LoVT.getVectorNumElements() to compute the boundary?


Repository:
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https://reviews.llvm.org/D97582