[PATCH] D118459: [ISEL] Canonicalize STEP_VECTOR to LHS if RHS is a splat.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:5644
+             N2.getOpcode() == ISD::STEP_VECTOR)
+      std::swap(N1, N2);
   }
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I expect we're going to need this for a lot of the DAG combines as well - is it worth adding a helper wrapper for isConstantIntBuildVectorOrConstantInt/isConstantFPBuildVectorOrConstantFP with SPLAT_VECTOR  and STEP_VECTOR as well?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D118459/new/

https://reviews.llvm.org/D118459