[PATCH] D83198: [CodeGen] Fix warnings in DAGTypeLegalizer::SplitVecOp_EXTRACT_SUBVECTOR

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


================
Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp:2183
+
+  assert(SubVT.isScalableVector() ==
+             N->getOperand(0).getValueType().isScalableVector() &&
----------------
I think this assert  is saying that this is not *yet* supported, because if extracting a fixed-width vector from a scalable vector is allowed then it should (at some point) also support extracting it from an illegal scalable vector.

So maybe better to change the wording to `"Extracting a fixed-length vector from a scalable vector is not yet supported"`, and perhaps you can wrap it in a `report_fatal_error(..)` instead of an assert, because this is more a `is-unsupported-error`.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D83198/new/

https://reviews.llvm.org/D83198