[PATCH] D25374: [DAGCombiner] Update most ADD combines to support general vector combines

[Simon Pilgrim via llvm-commits]

RKSimon added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:829
+    return !Const->isOpaque();
+  return ISD::isBuildVectorOfConstantSDNodes(N.getNode());
+}
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mkuper wrote:
> What if we have a BUILD_VECTOR of constants where one of the constants going into it is opaque?
I see what you're saying. For the current cases it won't have much effect - some of the combines would switch ops around but the expected constant folding will just fail. I'll change isNonOpaqueConstantOrConstantVector to check for opaques in the build vector, and make a separate isConstantOrConstantVector helper as well which we can use in a couple of places. Thorough tests of opaque vector elements might be tricky though.


Repository:
  rL LLVM

https://reviews.llvm.org/D25374