[FFmpeg-devel] manually hacked configure options increase h264 decoding speed significantly

Michael Niedermayer michaelni at gmx.at
Thu Oct 20 12:10:18 CEST 2011

On Thu, Oct 20, 2011 at 11:56:59AM +0200, madshi wrote:
> > 2011/10/20 Michael Niedermayer <michaelni at gmx.at>
> > a patch that autodetects their availability in configure
> > and uses them in mem.c if available is welcome
> > The existing autodetection has to be fixed, and its a
> > bit hard for me to do this without a mingw system to
> > test. Could you look into why it fails ?
> I wish I could do these things. Unfortunately I'm a
> mingw noob and haven't really looked into how the whole
> ffmpeg configuration system works at all. So I wouldn't
> really know where to start. I'm sorry...  :-(

for the configure side, it just tries to compile, link and run:
    (this needs -O3)

#include <signal.h>
static void sighandler(int sig){
int main(void){
    signal(SIGILL, sighandler);
    signal(SIGFPE, sighandler);
    signal(SIGSEGV, sighandler);
#ifdef SIGBUS
    signal(SIGBUS, sighandler);
    volatile int i=0;
    __asm__ volatile (
        "xorl %%ebp, %%ebp"
    ::: "%ebp");
    return i;

[... ]
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

If you think the mosad wants you dead since a long time then you are either
wrong or dead since a long time.
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