summaryrefslogtreecommitdiffstats
path: root/src/pulsecore/svolume.orc
diff options
context:
space:
mode:
authorArun Raghavan <arun.raghavan@collabora.co.uk>2010-10-25 17:59:08 +0100
committerArun Raghavan <arun.raghavan@collabora.co.uk>2011-03-05 14:38:28 +0530
commit4cd90d9e32ca9a23e3c0f7615974ea0c55ff3e49 (patch)
tree07d205c5607ab454d55e7ec7b02a1262bccf4946 /src/pulsecore/svolume.orc
parent516dd169b493e37c8445cb68831529020272d0d5 (diff)
volume: Add Orc-based optimised volume scaling
This adds volume scaling for 1- and 2-channel software volume scaling using Orc. While testing the MMX and SSE backends on a Core2, I see an ~2x performance benefit over the hand-rolled MMX and SSE code. Since I haven't been able to test on other architectures, the Orc code is only used when MMX/SSE* is present. This can be changed in the future after testing on AMD and ARM machines.
Diffstat (limited to 'src/pulsecore/svolume.orc')
-rw-r--r--src/pulsecore/svolume.orc84
1 files changed, 84 insertions, 0 deletions
diff --git a/src/pulsecore/svolume.orc b/src/pulsecore/svolume.orc
new file mode 100644
index 00000000..3411161c
--- /dev/null
+++ b/src/pulsecore/svolume.orc
@@ -0,0 +1,84 @@
+# This file is part of PulseAudio.
+#
+# Copyright 2010 Lennart Poettering
+# Copyright 2010 Wim Taymans <wim.taymans@collabora.co.uk>
+# Copyright 2010 Arun Raghavan <arun.raghavan@collabora.co.uk>
+#
+# PulseAudio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation; either version 2.1 of the License,
+# or (at your option) any later version.
+#
+# PulseAudio is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with PulseAudio; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+# USA.
+
+# S16NE 1- and 2-channel volume scaling work as follows:
+#
+# params: samples s (signed 16-bit), volume v (signed 32-bit < 2^31)
+#
+# 32 16 0 (type of operation)
+# sample = | sample | (signed)
+# s = | 0 | sample | (unsigned)
+#
+# if (sample < 0)
+# signc = | 0 | 0xffff | (unsigned)
+# else
+# signc = | 0 | 0 | (unsgined)
+#
+# if (sample < 0)
+# ml = | 0 | -((s*vl) >> 16) | (unsgined)
+# else
+# ml = | 0 | (s*vl) >> 16 | (unsgined)
+#
+# vh = | v >> 16 | (signed, but value is always signed
+# since PA_VOLUME_MAX is 0x0fffffff)
+# mh = | (s * vh) >> 16 | (signed)
+# ml = | ml + mh | (signed)
+# sample = | (ml >> 16) | (signed, saturated)
+
+.function pa_volume_s16ne_orc_1ch
+.dest 2 samples int16_t
+.param 4 v int32_t
+.temp 2 vh
+.temp 4 s
+.temp 4 mh
+.temp 4 ml
+.temp 4 signc
+
+convuwl s, samples
+x2 cmpgtsw signc, 0, s
+x2 andw signc, signc, v
+x2 mulhuw ml, s, v
+subl ml, ml, signc
+convhlw vh, v
+mulswl mh, samples, vh
+addl ml, ml, mh
+convssslw samples, ml
+
+.function pa_volume_s16ne_orc_2ch
+.dest 4 samples int16_t
+.longparam 8 vols
+.temp 8 v
+.temp 4 vh
+.temp 8 s
+.temp 8 mh
+.temp 8 ml
+.temp 8 signc
+
+loadpq v, vols
+x2 convuwl s, samples
+x4 cmpgtsw signc, 0, s
+x4 andw signc, signc, v
+x4 mulhuw ml, s, v
+x2 subl ml, ml, signc
+x2 convhlw vh, v
+x2 mulswl mh, samples, vh
+x2 addl ml, ml, mh
+x2 convssslw samples, ml