[PATCH] D126449: [AArch64] Reuse larger DUP if available

[Sam Tebbs via Phabricator via llvm-commits]

samtebbs added inline comments.


================
Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:18155
+      return DCI.DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, VT, SDValue(LN, 0),
+                             DCI.DAG.getConstant(0, DL, MVT::i64));
+    }
----------------
In `tryExtendDUPToExtractHigh` above, the `EXTRACT_SUBVECTOR` gets `NumElems` as the constant, but this one gets 0. Why is it 0 in this case? Seems like an odd number to give `EXTRACT_SUBVECTOR`.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D126449/new/

https://reviews.llvm.org/D126449