[PATCH] D67841: [SLP] avoid reduction transform on patterns that the backend can load-combine

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/lib/Analysis/TargetTransformInfo.cpp:633
+  // Check if we can match this instruction as part of a larger pattern.
+  Optional<int> LoadCombineCost = getLoadCombineCost(Opcode, Ty, Args);
+  if (LoadCombineCost)
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Ooops, sorry, my fault, pointed to the wrong function. Better to modify a function in `include/llvm/CodeGen/BasicTTIImpl.h`, `BasicTTIImplBase::getArithmeticInstrCost`, if this is common limitation.


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Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:6500
+          TargetTransformInfo::OK_AnyValue, TargetTransformInfo::OP_None,
+          TargetTransformInfo::OP_None, { FirstReducedVal });
       break;
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I don't think it is a good idea to break the contract of the function. Better to pass the arguments of the instruction, just like requested by the function.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67841/new/

https://reviews.llvm.org/D67841