[PATCH] D29454: [DAGCombine] RFC: Recognise any_extend_vector_inreg and truncation style shuffle masks

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:14245
+      return SDValue();
+    if (!IsAnyExtend(Scale))
+      continue;
----------------
delena wrote:
> lower case function name: isAnyExtend
Ah - missed that thanks - we're not very consistent when it comes to these.....


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:14250
+    EVT OutVT = EVT::getVectorVT(*DAG.getContext(), OutSVT, NumElts / Scale);
+    if (!LegalOperations ||
+        TLI.isOperationLegalOrCustom(ISD::ANY_EXTEND_VECTOR_INREG, OutVT))
----------------
delena wrote:
> Is !LegalOperations important?
For these cases yes - currently ISD::ANY_EXTEND_VECTOR_INREG isn't supported by any targets as a legal/custom operation but should be soon.


Repository:
  rL LLVM

https://reviews.llvm.org/D29454