[FFmpeg-devel] Patch: Inline asm fixes for Intel compiler on Windows

Michael Niedermayer michaelni at gmx.at
Mon Apr 7 13:35:38 CEST 2014

On Mon, Apr 07, 2014 at 04:29:32PM +1000, Matt Oliver wrote:
> > this patch breaks fate-vp6a-skip_alpha, fate-vp6f and fate-vp6a
> > possibly also others, didnt test with -k
> Interesting, I always run a local FATE test before submitting anything and
> it worked fine on mine so that would suggest it is compiler dependent.
> I think all the in-out parameters must be +& instead of just +.
> > Note that this was incorrect even before, but it probably
> > shows up only now since now it is trivial for the compiler
> > to figure out that c->code_word and code_word are the same thing,
> > and without early clobber it can place them onto the same register.
> > This of course invalidates all previous benchmarks...
> Thanks, I was scratching my head trying to work out what was going on (as
> stated previously fate worked for me). I was trying to keep the patch to a
> minimum change wise so it never occurred to me to check that the
> constraints were correct even in the current git master.
> I have updated the constraints and, fate still tests as correct using my
> compilers. I reran the benchmarks and got a slight change in performance
> but its still 4.6% faster.

>  vp56_arith.h |   13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 1421f9dacaf77b65e802781eaf8b09ee873e7be6  Remove-leal-op-to-fix-icl-inline-asm.patch
> From 97a73c83c9f9202d2d20911a5cf738b6491f7111 Mon Sep 17 00:00:00 2001
> From: Matt Oliver <protogonoi at gmail.com>
> Date: Mon, 7 Apr 2014 13:25:28 +1000
> Subject: [PATCH] Remove leal op to fix icl inline asm.




Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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