[PATCH] D23897: [SelectionDAG] Generate vector_shuffle nodes for undersized result vector sizes

[Simon Pilgrim via llvm-commits]

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

LGTM - with one minor.


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Comment at: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:3090
@@ +3089,3 @@
+    for (unsigned i = MaskNumElts; i != PaddedMaskNumElts; ++i)
+      MappedOps.push_back(-1);
+
----------------
Possibly remove this, initialize as MappedOps(PaddedMaskNumElts, -1) and then just insert MappedOps[i] = Idx in the readjustment loop.


https://reviews.llvm.org/D23897