[PATCH] D29000: [SelectionDAG] Teach getNode to simplify a couple easy cases of EXTRACT_SUBVECTOR

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon accepted this revision.
RKSimon added a comment.
This revision is now accepted and ready to land.

LGTM



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Comment at: lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4094
+      if (N2C && N1.getOpcode() == ISD::CONCAT_VECTORS &&
+          N1.getNumOperands() > 0 &&
+          VT == N1.getOperand(0).getValueType()) {
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Not sure if this will ever be needed? A concat of 0 vectors should have asserted at creation surely?


https://reviews.llvm.org/D29000