This patch accelerates FLAC__lpc_compute_autocorrelation_intrin_sse_lag_NN
routines for AMD and newer Intel CPUs. But it's slower on older Intel CPUs.
('Newer Intel CPUs' means Core i aka Nehalem and newer)
According to tests at HA:
<http://www.hydrogenaud.io/forums/index.php?s=&showtopic=101082&view=findpost&p=870753>
CPU flac -5 flac -8
Athlon XP +5 % +2.4 %
Athlon 64 X2 +9 % +4 %
Core i +7 % +1 % ... +2.7 %
Core 2 ? -3.5 %
According to Steam HW survey <http://store.steampowered.com/hwsurvey/>
69% of Steam users have SSE4.2 which means that the new code is faster for them.
There are also AMD users that don't have SSE4.2, so I think that about 75%
of Steam users will benefit from this patch.
(If somebody knows a better source of stat data please tell.)
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Erik de Castro Lopo
2014-Aug-09 02:55 UTC
[flac-dev] [PATCH] new SSE code to calculate autocorrelation
lvqcl wrote:> This patch accelerates FLAC__lpc_compute_autocorrelation_intrin_sse_lag_NN > routines for AMD and newer Intel CPUs. But it's slower on older Intel CPUs. > ('Newer Intel CPUs' means Core i aka Nehalem and newer)Applied. Thanks. Erik -- ---------------------------------------------------------------------- Erik de Castro Lopo http://www.mega-nerd.com/