[PATCH] D18566: [x86] use SSE/AVX ops for non-zero memsets (PR27100)

Zia Ansari via llvm-commits llvm-commits at lists.llvm.org
Tue Mar 29 13:22:48 PDT 2016


zansari added a comment.

Depending on the cost of imull, you can avoid it with:

  movzbl    4(%esp), %ecx
  movl      %ecx, %eax
  shll      $8, %eax
  orl       %eax, %ecx
  movl      %ecx, %edx
  shll      $16, %edx
  orl       %edx, %ecx
  movd      %ecx, %xmm0
  pshufd    $0, %xmm0, %xmm1


http://reviews.llvm.org/D18566





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