[PATCH] D125527: [CostModel][X86] getScalarizationOverhead - improve extraction costs for > 128-bit vectors

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/lib/Target/X86/X86TargetTransformInfo.cpp:3898
+
+        Cost += DemandedUpper128Lanes.countPopulation();
+
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Can we estimate regcopy somehow here?


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Comment at: llvm/lib/Target/X86/X86TargetTransformInfo.cpp:3905
+            unsigned Idx = I % Scale;
+            Cost += getVectorInstrCost(Instruction::ExtractElement, Ty, Idx);
+          }
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Maybe use BaseT::getScalarizationOverhead again here rather than `getVectorInstrCost(Instruction::ExtractElement`? Also, what about possible getExtractWithExtendCost here?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D125527/new/

https://reviews.llvm.org/D125527