1/*
2 * Copyright (C) 2010 Mans Rullgard <mans@mansr.com>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#ifndef AVCODEC_ARM_VP56_ARITH_H
22#define AVCODEC_ARM_VP56_ARITH_H
23
24#if CONFIG_THUMB
25#   define A(x)
26#   define T(x) x
27#else
28#   define A(x) x
29#   define T(x)
30#endif
31
32#if CONFIG_THUMB || defined __clang__
33#   define L(x)
34#   define U(x) x
35#else
36#   define L(x) x
37#   define U(x)
38#endif
39
40#if HAVE_ARMV6_INLINE
41
42#define vp56_rac_get_prob vp56_rac_get_prob_armv6
43static inline int vp56_rac_get_prob_armv6(VP56RangeCoder *c, int pr)
44{
45    unsigned shift     = ff_vp56_norm_shift[c->high];
46    unsigned code_word = c->code_word << shift;
47    unsigned high      = c->high << shift;
48    unsigned bit;
49
50    __asm__ ("adds    %3,  %3,  %0           \n"
51             "itt     cs                     \n"
52             "cmpcs   %7,  %4                \n"
53           L("ldrcsh  %2,  [%4], #2          \n")
54           U("ldrhcs  %2,  [%4], #2          \n")
55             "rsb     %0,  %6,  #256         \n"
56             "smlabb  %0,  %5,  %6,  %0      \n"
57           T("itttt   cs                     \n")
58             "rev16cs %2,  %2                \n"
59           T("lslcs   %2,  %2,  %3           \n")
60           T("orrcs   %1,  %1,  %2           \n")
61           A("orrcs   %1,  %1,  %2,  lsl %3  \n")
62             "subcs   %3,  %3,  #16          \n"
63             "lsr     %0,  %0,  #8           \n"
64             "cmp     %1,  %0,  lsl #16      \n"
65             "ittte   ge                     \n"
66             "subge   %1,  %1,  %0,  lsl #16 \n"
67             "subge   %0,  %5,  %0           \n"
68             "movge   %2,  #1                \n"
69             "movlt   %2,  #0                \n"
70             : "=&r"(c->high), "=&r"(c->code_word), "=&r"(bit),
71               "+&r"(c->bits), "+&r"(c->buffer)
72             : "r"(high), "r"(pr), "r"(c->end - 1),
73               "0"(shift), "1"(code_word)
74             : "cc");
75
76    return bit;
77}
78
79#define vp56_rac_get_prob_branchy vp56_rac_get_prob_branchy_armv6
80static inline int vp56_rac_get_prob_branchy_armv6(VP56RangeCoder *c, int pr)
81{
82    unsigned shift     = ff_vp56_norm_shift[c->high];
83    unsigned code_word = c->code_word << shift;
84    unsigned high      = c->high << shift;
85    unsigned low;
86    unsigned tmp;
87
88    __asm__ ("adds    %3,  %3,  %0           \n"
89             "itt     cs                     \n"
90             "cmpcs   %7,  %4                \n"
91           L("ldrcsh  %2,  [%4], #2          \n")
92           U("ldrhcs  %2,  [%4], #2          \n")
93             "rsb     %0,  %6,  #256         \n"
94             "smlabb  %0,  %5,  %6,  %0      \n"
95           T("itttt   cs                     \n")
96             "rev16cs %2,  %2                \n"
97           T("lslcs   %2,  %2,  %3           \n")
98           T("orrcs   %1,  %1,  %2           \n")
99           A("orrcs   %1,  %1,  %2,  lsl %3  \n")
100             "subcs   %3,  %3,  #16          \n"
101             "lsr     %0,  %0,  #8           \n"
102             "lsl     %2,  %0,  #16          \n"
103             : "=&r"(low), "+&r"(code_word), "=&r"(tmp),
104               "+&r"(c->bits), "+&r"(c->buffer)
105             : "r"(high), "r"(pr), "r"(c->end - 1), "0"(shift)
106             : "cc");
107
108    if (code_word >= tmp) {
109        c->high      = high - low;
110        c->code_word = code_word - tmp;
111        return 1;
112    }
113
114    c->high      = low;
115    c->code_word = code_word;
116    return 0;
117}
118
119#endif
120
121#endif /* AVCODEC_ARM_VP56_ARITH_H */
122