On 10/24/2015 7:48 PM, Ganesh Ajjanagadde wrote: > On Sat, Oct 24, 2015 at 6:08 PM, James Almer <jamr...@gmail.com> wrote: >> This gives the compiler some flexibility >> >> Signed-off-by: James Almer <jamr...@gmail.com> >> --- >> libavutil/x86/intmath.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/libavutil/x86/intmath.h b/libavutil/x86/intmath.h >> index 7881e3c..10d3e7f 100644 >> --- a/libavutil/x86/intmath.h >> +++ b/libavutil/x86/intmath.h >> @@ -36,7 +36,7 @@ static av_always_inline av_const int ff_ctzll_x86(long >> long v) >> { >> # if ARCH_X86_64 >> uint64_t c; >> - __asm__("bsfq %1,%0" : "=r" (c) : "r" (v)); >> + __asm__ ("bsfq %1,%0" : "=r" (c) : "rm" (v)); >> return c; >> # else >> return ((uint32_t)v == 0) ? _bit_scan_forward((uint32_t)(v >> 32)) + 32 >> : _bit_scan_forward((uint32_t)v); >> -- >> 2.6.2 > > This question may be silly, but can you clarify when this asm code is > used instead of __builtin_ctzll? For instance, I think on GNU/Linux, > x86-64, sufficiently modern GCC (even with asm enabled), we should > always use the builtin: the compiler knows best what to do with its > builtin.
This is ICC/ICL, not GCC. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel