[PATCH] D107651: [AArch64][SVE] Teach cost model that masked loads/stores are cheap

[Bradley Smith via Phabricator via llvm-commits]

bsmith added reviewers: paulwalker-arm, peterwaller-arm.
bsmith added inline comments.


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Comment at: llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp:1516
 
-  return LT.first * 2;
+  return isa<ScalableVectorType>(Src) ? LT.first * 2 : LT.first * 2 + LT.first;
 }
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What's the rationale behind this cost for fixed types?


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Comment at: llvm/test/Analysis/CostModel/AArch64/masked_ldst.ll:2
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
 ; RUN: opt < %s -cost-model -analyze -mtriple=aarch64-linux-gnu -mattr=+sve | FileCheck %s
 
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This test is for scalable types, hence the changes in here are testing the cost of scalable masked loads/stores rather than fixed ones. You'll need to add functions (probably in another test file) that use the vscale_range attribute to specify various different fixed vector lengths)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D107651/new/

https://reviews.llvm.org/D107651