intmath.h
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1 /*
2  * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVUTIL_ARM_INTMATH_H
22 #define AVUTIL_ARM_INTMATH_H
23 
24 #include <stdint.h>
25 
26 #include "config.h"
27 #include "libavutil/attributes.h"
28 
29 #if HAVE_INLINE_ASM
30 
31 #if HAVE_ARMV6
32 
33 #define FASTDIV FASTDIV
34 static av_always_inline av_const int FASTDIV(int a, int b)
35 {
36  int r;
37  __asm__ ("cmp %2, #2 \n\t"
38  "ldr %0, [%3, %2, lsl #2] \n\t"
39  "ite le \n\t"
40  "lsrle %0, %1, #1 \n\t"
41  "smmulgt %0, %0, %1 \n\t"
42  : "=&r"(r) : "r"(a), "r"(b), "r"(ff_inverse) : "cc");
43  return r;
44 }
45 
46 #define av_clip_uint8 av_clip_uint8_arm
47 static av_always_inline av_const uint8_t av_clip_uint8_arm(int a)
48 {
49  unsigned x;
50  __asm__ ("usat %0, #8, %1" : "=r"(x) : "r"(a));
51  return x;
52 }
53 
54 #define av_clip_int8 av_clip_int8_arm
55 static av_always_inline av_const uint8_t av_clip_int8_arm(int a)
56 {
57  unsigned x;
58  __asm__ ("ssat %0, #8, %1" : "=r"(x) : "r"(a));
59  return x;
60 }
61 
62 #define av_clip_uint16 av_clip_uint16_arm
63 static av_always_inline av_const uint16_t av_clip_uint16_arm(int a)
64 {
65  unsigned x;
66  __asm__ ("usat %0, #16, %1" : "=r"(x) : "r"(a));
67  return x;
68 }
69 
70 #define av_clip_int16 av_clip_int16_arm
71 static av_always_inline av_const int16_t av_clip_int16_arm(int a)
72 {
73  int x;
74  __asm__ ("ssat %0, #16, %1" : "=r"(x) : "r"(a));
75  return x;
76 }
77 
78 #define av_clip_uintp2 av_clip_uintp2_arm
79 static av_always_inline av_const unsigned av_clip_uintp2_arm(int a, int p)
80 {
81  unsigned x;
82  __asm__ ("usat %0, %2, %1" : "=r"(x) : "r"(a), "i"(p));
83  return x;
84 }
85 
86 
87 #else /* HAVE_ARMV6 */
88 
89 #define FASTDIV FASTDIV
90 static av_always_inline av_const int FASTDIV(int a, int b)
91 {
92  int r, t;
93  __asm__ ("umull %1, %0, %2, %3"
94  : "=&r"(r), "=&r"(t) : "r"(a), "r"(ff_inverse[b]));
95  return r;
96 }
97 
98 #endif /* HAVE_ARMV6 */
99 
100 #define av_clipl_int32 av_clipl_int32_arm
101 static av_always_inline av_const int32_t av_clipl_int32_arm(int64_t a)
102 {
103  int x, y;
104  __asm__ ("adds %1, %R2, %Q2, lsr #31 \n\t"
105  "itet ne \n\t"
106  "mvnne %1, #1<<31 \n\t"
107  "moveq %0, %Q2 \n\t"
108  "eorne %0, %1, %R2, asr #31 \n\t"
109  : "=r"(x), "=&r"(y) : "r"(a));
110  return x;
111 }
112 
113 #endif /* HAVE_INLINE_ASM */
114 
115 #endif /* AVUTIL_ARM_INTMATH_H */