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PING: PATCH: Add --with-math=sse for x86


On Mon, Aug 11, 2008 at 9:12 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> Hi,
>
> This is the updated patch to provide a configure option,
> --with-math=sse, for i386 targets. It will enable -msse2
> -mfpmath=sse by default.  Its benefits are
>
> 1. Improve 32bit FP performance significantly on current
> x86 processors without changing Makefiles. SPEC CPU
> FP can be improved by as much as 20%.
> 2. A new psABI designed for SSE math won't happen
> in the foreseeable future.  -with-math=sse provides a
> a way to improve FP performance with backward binary
> compatibility.
> 3. The performance gain is automatic since it requires
> very few changes in software packages if any changes
> are needed at all.
> 4. MacOS chose Linux psABI with SSE math enabled by
> default and increased alignment when they defined a new
> psABI. It is an indication that SSE math can be used on
> entire OS with improved FP performance.
>
> OK for trunk?
>
> Thanks.
>
>
> --
> H.J.
> ---
> 2008-08-11  H.J. Lu  <hongjiu.lu@intel.com>
>
>        * config.gcc: Support --with-math=sse for x86.
>
>        * config/i386/ssemath.h: New.
>
>        * doc/install.texi (--with-math=sse): Documented.
>

PING.

-- 
H.J.


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