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FFmpeg/libavcodec/arm/mpegvideo_armv5te_s.S
Michael Niedermayer 686959e87e Merge remote-tracking branch 'qatar/master'
* qatar/master:
  doxygen: Consistently use '@' instead of '\' for Doxygen markup.
  Use av_printf_format to check the usage of printf style functions
  Add av_printf_format, for marking printf style format strings and their parameters
  ARM: enable thumb for Cortex-M* CPUs
  nsvdec: Propagate error values instead of returning 0 in nsv_read_header().
  build: remove SRC_PATH_BARE variable
  build: move basic rules and variables to main Makefile
  build: move special targets to end of main Makefile
  lavdev: improve feedback in case of invalid frame rate/size
  vfwcap: prefer "framerate_q" over "fps" in vfw_read_header()
  v4l2: prefer "framerate_q" over "fps" in v4l2_set_parameters()
  fbdev: prefer "framerate_q" over "fps" in device context
  bktr: prefer "framerate" over "fps" for grab_read_header()
  ALSA: implement channel layout for playback.
  alsa: support unsigned variants of already supported signed formats.
  alsa: add support for more formats.
  ARM: allow building in Thumb2 mode

Conflicts:
	common.mak
	doc/APIchanges
	libavcodec/vdpau.h
	libavdevice/alsa-audio-common.c
	libavdevice/fbdev.c
	libavdevice/libdc1394.c
	libavutil/avutil.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2011-06-24 03:07:04 +02:00

115 lines
3.9 KiB
ArmAsm

/*
* Optimization of some functions from mpegvideo.c for armv5te
* Copyright (c) 2007 Siarhei Siamashka <ssvb@users.sourceforge.net>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "asm.S"
/*
* Special optimized version of dct_unquantize_h263_helper_c, it
* requires the block to be at least 8 bytes aligned, and may process
* more elements than requested. But it is guaranteed to never
* process more than 64 elements provided that count argument is <= 64,
* so it is safe. This function is optimized for a common distribution
* of values for nCoeffs (they are mostly multiple of 8 plus one or
* two extra elements). So this function processes data as 8 elements
* per loop iteration and contains optional 2 elements processing in
* the end.
*
* Inner loop should take 6 cycles per element on arm926ej-s (Nokia 770)
*/
.macro dequant_t dst, src, mul, add, tmp
rsbs \tmp, ip, \src, asr #16
it gt
addgt \tmp, \add, #0
it lt
rsblt \tmp, \add, #0
it ne
smlatbne \dst, \src, \mul, \tmp
.endm
.macro dequant_b dst, src, mul, add, tmp
rsbs \tmp, ip, \src, lsl #16
it gt
addgt \tmp, \add, #0
it lt
rsblt \tmp, \add, #0
it ne
smlabbne \dst, \src, \mul, \tmp
.endm
function ff_dct_unquantize_h263_armv5te, export=1
push {r4-r9,lr}
mov ip, #0
subs r3, r3, #2
ble 2f
ldrd r4, [r0, #0]
1:
ldrd r6, [r0, #8]
dequant_t r9, r4, r1, r2, r9
dequant_t lr, r5, r1, r2, lr
dequant_b r4, r4, r1, r2, r8
dequant_b r5, r5, r1, r2, r8
strh r4, [r0], #2
strh r9, [r0], #2
strh r5, [r0], #2
strh lr, [r0], #2
dequant_t r9, r6, r1, r2, r9
dequant_t lr, r7, r1, r2, lr
dequant_b r6, r6, r1, r2, r8
dequant_b r7, r7, r1, r2, r8
strh r6, [r0], #2
strh r9, [r0], #2
strh r7, [r0], #2
strh lr, [r0], #2
subs r3, r3, #8
it gt
ldrdgt r4, [r0, #0] /* load data early to avoid load/use pipeline stall */
bgt 1b
adds r3, r3, #2
it le
pople {r4-r9,pc}
2:
ldrsh r9, [r0, #0]
ldrsh lr, [r0, #2]
mov r8, r2
cmp r9, #0
it lt
rsblt r8, r2, #0
it ne
smlabbne r9, r9, r1, r8
mov r8, r2
cmp lr, #0
it lt
rsblt r8, r2, #0
it ne
smlabbne lr, lr, r1, r8
strh r9, [r0], #2
strh lr, [r0], #2
pop {r4-r9,pc}
endfunc