[FFmpeg-cvslog] r12512 - trunk/libavcodec/i386/dsputil_mmx.c

[İsmail Dönmez]

On Fri, Mar 21, 2008 at 1:55 AM, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Fri, Mar 21, 2008 at 12:16:53AM +0200, Uoti Urpala wrote:
>  > On Thu, 2008-03-20 at 14:52 -0700, Mike Melanson wrote:
>  > > michael wrote:
>  > > > Log:
>  > > > Hardcode register to prevent aparent miscompilation.
>  > > > Fixes regression tests with gcc 2.95.
>  > >
>  > > Awesome. FATE thanks you. :)
>  >
>  > Not so awesome for people with working compilers. The change makes the
>  > code worse for the sake of working around bugs in an obsolete compiler.
>
>  #define uoti_worse_code supports_gcc2_95()
>
>  Anyway, the "worse" code should be faster, as it uses a register where the old
>  could use memory. Also the gcc 2.95 bug helped finding a unused temp variable
>  (see previous commit) removing that surely improved speed.

"should be" faster? You always require people to benchmark first
before changing such code, did you actually benchmarked your change?

-- 
Never learn by your mistakes, if you do you may never dare to try again.