[PATCH] D64805: [AArch64] Don't call bcmp for small byte comparisons

[Sjoerd Meijer via Phabricator via llvm-commits]

SjoerdMeijer added inline comments.


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Comment at: llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp:625
+  Options.MaxNumLoads = TLI->getMaxExpandSizeMemcmp(OptSize);
+  Options.NumLoadsPerBlock = 2;
+  Options.AllowOverlappingLoads = true;
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why 2?


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Comment at: llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp:626
+  Options.NumLoadsPerBlock = 2;
+  Options.AllowOverlappingLoads = true;
+  Options.LoadSizes.push_back(8);
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How about vector loads and alignment? Can we generate them for this, and do we then also need 16 byte loads to loadsizes?


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Comment at: llvm/test/CodeGen/AArch64/bcmp-inline-small.ll:2
+; RUN: llc < %s -mtriple=aarch64-linux-gnu | FileCheck %s
+
+; CHECK-LABEL: bcmp_b2:
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I think tests are missing for:
- code-size
- edge cases for NumLoadsPerBlock and MaxNumLoads


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D64805/new/

https://reviews.llvm.org/D64805