diff options
Diffstat (limited to 'libavcodec/arm/mpegvideo_armv5te_s.S')
| -rw-r--r-- | libavcodec/arm/mpegvideo_armv5te_s.S | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/libavcodec/arm/mpegvideo_armv5te_s.S b/libavcodec/arm/mpegvideo_armv5te_s.S new file mode 100644 index 0000000000..aaa252d3b7 --- /dev/null +++ b/libavcodec/arm/mpegvideo_armv5te_s.S @@ -0,0 +1,117 @@ +/* + * 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) + */ +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] + + rsbs r9, ip, r4, asr #16 + addgt r9, r2, #0 + rsblt r9, r2, #0 + smlatbne r9, r4, r1, r9 + + rsbs lr, ip, r5, asr #16 + addgt lr, r2, #0 + rsblt lr, r2, #0 + smlatbne lr, r5, r1, lr + + rsbs r8, ip, r4, asl #16 + addgt r8, r2, #0 + rsblt r8, r2, #0 + smlabbne r4, r4, r1, r8 + + rsbs r8, ip, r5, asl #16 + addgt r8, r2, #0 + rsblt r8, r2, #0 + smlabbne r5, r5, r1, r8 + + strh r4, [r0], #2 + strh r9, [r0], #2 + strh r5, [r0], #2 + strh lr, [r0], #2 + + rsbs r9, ip, r6, asr #16 + addgt r9, r2, #0 + rsblt r9, r2, #0 + smlatbne r9, r6, r1, r9 + + rsbs lr, ip, r7, asr #16 + addgt lr, r2, #0 + rsblt lr, r2, #0 + smlatbne lr, r7, r1, lr + + rsbs r8, ip, r6, asl #16 + addgt r8, r2, #0 + rsblt r8, r2, #0 + smlabbne r6, r6, r1, r8 + + rsbs r8, ip, r7, asl #16 + addgt r8, r2, #0 + rsblt r8, r2, #0 + smlabbne r7, r7, r1, r8 + + strh r6, [r0], #2 + strh r9, [r0], #2 + strh r7, [r0], #2 + strh lr, [r0], #2 + + subs r3, r3, #8 + ldrgtd r4, [r0, #0] /* load data early to avoid load/use pipeline stall */ + bgt 1b + + adds r3, r3, #2 + pople {r4-r9,pc} +2: + ldrsh r9, [r0, #0] + ldrsh lr, [r0, #2] + mov r8, r2 + cmp r9, #0 + rsblt r8, r2, #0 + smlabbne r9, r9, r1, r8 + mov r8, r2 + cmp lr, #0 + rsblt r8, r2, #0 + smlabbne lr, lr, r1, r8 + strh r9, [r0], #2 + strh lr, [r0], #2 + pop {r4-r9,pc} + .endfunc |