[PATCH] D67259: [X86] Enable -mprefer-vector-width=256 by default for Skylake-avx512 and later Intel CPUs.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/test/Transforms/LoopVectorize/X86/pr42674.ll:2
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt %s -loop-vectorize -instcombine -simplifycfg -mtriple=x86_64-unknown-linux-gnu -mcpu=skylake-avx512 -S | FileCheck %s
+; RUN: opt %s -loop-vectorize -instcombine -simplifycfg -mtriple=x86_64-unknown-linux-gnu -mcpu=skylake-avx512 -mattr=-prefer-256-bit -S | FileCheck %s
 
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Would we be better off using -mattr=avx512f,avx512dq,avx512bw instead -mcpu=skylake-avx512?


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/sqrt.ll:6
 ; RUN: opt < %s -mtriple=x86_64-unknown -mcpu=core-avx2 -basicaa -slp-vectorizer -S | FileCheck %s --check-prefix=CHECK --check-prefix=AVX --check-prefix=AVX256
-; RUN: opt < %s -mtriple=x86_64-unknown -mcpu=skylake-avx512 -basicaa -slp-vectorizer -S | FileCheck %s --check-prefix=CHECK --check-prefix=AVX --check-prefix=AVX512
+; RUN: opt < %s -mtriple=x86_64-unknown -mcpu=skylake-avx512 -mattr=-prefer-256-bit -basicaa -slp-vectorizer -S | FileCheck %s --check-prefix=CHECK --check-prefix=AVX --check-prefix=AVX512
 
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Would we be better off changing all these from -mcpu to -mattr instead?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67259/new/

https://reviews.llvm.org/D67259