Patchwork [Google] X86_TUNE_USE_VECTOR_CONVERTS adjustment

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Submitter Wei Mi
Date Aug. 15, 2013, 4:50 p.m.
Message ID <CA+4CFy5yrLmyKSJpGe31SR756GzuPDgaQbyTyqKPY9wi0_3o1g@mail.gmail.com>
Download mbox | patch
Permalink /patch/267406/
State New
Headers show

Comments

Wei Mi - Aug. 15, 2013, 4:50 p.m.
Turning off X86_TUNE_USE_VECTOR_CONVERTS uses cvtss2sd instead of
unpcklps+cvtps2pd, which is better for some recent intel micro arch
such as westmere and sandybridge. So turn it off for m_GENERIC and
m_CORE_ALL.

regression and bootstrap ok. ok for 4.8 branch?
Xinliang David Li - Aug. 15, 2013, 5:09 p.m.
yes.

thanks,

David

On Thu, Aug 15, 2013 at 9:50 AM, Wei Mi <wmi@google.com> wrote:
> Turning off X86_TUNE_USE_VECTOR_CONVERTS uses cvtss2sd instead of
> unpcklps+cvtps2pd, which is better for some recent intel micro arch
> such as westmere and sandybridge. So turn it off for m_GENERIC and
> m_CORE_ALL.
>
> regression and bootstrap ok. ok for 4.8 branch?
>
> Index: config/i386/i386.c
> ===================================================================
> --- config/i386/i386.c (revision 201675)
> +++ config/i386/i386.c (working copy)
> @@ -1995,7 +1995,7 @@ static unsigned int initial_ix86_tune_fe
>
>    /* X86_TUNE_USE_VECTOR_FP_CONVERTS: Prefer vector packed SSE conversion
>       from FP to FP. */
> -  m_CORE_ALL | m_AMDFAM10 | m_GENERIC,
> +  m_AMDFAM10,
>
>    /* X86_TUNE_USE_VECTOR_CONVERTS: Prefer vector packed SSE conversion
>       from integer to FP. */

Patch

Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c (revision 201675)
+++ config/i386/i386.c (working copy)
@@ -1995,7 +1995,7 @@  static unsigned int initial_ix86_tune_fe

   /* X86_TUNE_USE_VECTOR_FP_CONVERTS: Prefer vector packed SSE conversion
      from FP to FP. */
-  m_CORE_ALL | m_AMDFAM10 | m_GENERIC,
+  m_AMDFAM10,

   /* X86_TUNE_USE_VECTOR_CONVERTS: Prefer vector packed SSE conversion
      from integer to FP. */