[PATCH] D75348: [DAGCombiner] recognize shuffle (shuffle X, Mask0), Mask --> splat X

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:19298
+  }
+  assert(all_of(NewMask, [](int M) { return M == -1; }) ||
+         getSplatIndex(NewMask) != -1 && "Expected a splat mask");
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Check for isShuffleMaskLegal() ?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75348/new/

https://reviews.llvm.org/D75348