1/**
2 * VP5 and VP6 compatible video decoder (arith decoder)
3 *
4 * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
5 * Copyright (C) 2010  Eli Friedman
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#ifndef AVCODEC_X86_VP56_ARITH_H
25#define AVCODEC_X86_VP56_ARITH_H
26
27#if HAVE_INLINE_ASM && HAVE_FAST_CMOV && HAVE_6REGS
28#include "libavutil/attributes.h"
29
30#define vp56_rac_get_prob vp56_rac_get_prob
31static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
32{
33    unsigned int code_word = vp56_rac_renorm(c);
34    unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
35    unsigned int low_shift = low << 16;
36    int bit = 0;
37    c->code_word = code_word;
38
39    __asm__(
40        "subl  %4, %1      \n\t"
41        "subl  %3, %2      \n\t"
42        "setae %b0         \n\t"
43        "cmovb %4, %1      \n\t"
44        "cmovb %5, %2      \n\t"
45        : "+q"(bit), "+&r"(c->high), "+&r"(c->code_word)
46        : "r"(low_shift), "r"(low), "r"(code_word)
47    );
48
49    return bit;
50}
51#endif
52
53#endif /* AVCODEC_X86_VP56_ARITH_H */
54