[FFmpeg-cvslog] x86/cpu: set avxslow cpuflag on btver2 CPUs
James Almer
git at videolan.org
Sun Feb 7 20:40:33 CET 2016
ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Sun Feb 7 00:04:59 2016 -0300| [be22bd32fe433588f26aad40db971e0154d7f904] | committer: James Almer
x86/cpu: set avxslow cpuflag on btver2 CPUs
They are also slow when using 256 bit wide registers
Reviewed-by: Hendrik Leppkes <h.leppkes at gmail.com>
Signed-off-by: James Almer <jamrial at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=be22bd32fe433588f26aad40db971e0154d7f904
---
libavutil/x86/cpu.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/libavutil/x86/cpu.c b/libavutil/x86/cpu.c
index f57d72d..bb63daa 100644
--- a/libavutil/x86/cpu.c
+++ b/libavutil/x86/cpu.c
@@ -182,13 +182,11 @@ int ff_get_cpu_flags_x86(void)
/* Similar to the above but for AVX functions on AMD processors.
This is necessary only for functions using YMM registers on Bulldozer
- based CPUs as they lack 256-bits execution units. SSE/AVX functions
- using XMM registers are always faster on them.
+ and Jaguar based CPUs as they lack 256-bits execution units. SSE/AVX
+ functions using XMM registers are always faster on them.
AV_CPU_FLAG_AVX and AV_CPU_FLAG_AVXSLOW are both set so that AVX is
- used unless explicitly disabled by checking AV_CPU_FLAG_AVXSLOW.
- TODO: Confirm if Excavator is affected or not by this once it's
- released, and update the check if necessary. Same for btver2. */
- if (family == 0x15 && (rval & AV_CPU_FLAG_AVX))
+ used unless explicitly disabled by checking AV_CPU_FLAG_AVXSLOW. */
+ if ((family == 0x15 || family == 0x16) && (rval & AV_CPU_FLAG_AVX))
rval |= AV_CPU_FLAG_AVXSLOW;
}
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