[PATCH] D42090: [DAGCombiner] Add a DAG combine to turn a splat build_vector where the splat elemnt is a bitcast from a vector type into a concat_vector

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:14952
+  // concat_vector.
+  if (SDValue Splat = cast<BuildVectorSDNode>(N)->getSplatValue()) {
+    if (Splat.getOpcode() == ISD::BITCAST) {
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Also, should this be limited to before LegalOperations in case a backend is trying to do this in reverse?


https://reviews.llvm.org/D42090