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mathops.h
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1 /*
2  * simple math operations
3  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVCODEC_ARM_MATHOPS_H
23 #define AVCODEC_ARM_MATHOPS_H
24 
25 #include <stdint.h>
26 #include "config.h"
27 #include "libavutil/common.h"
28 
29 #if HAVE_INLINE_ASM
30 
31 #if HAVE_ARMV6_INLINE
32 #define MULH MULH
33 static inline av_const int MULH(int a, int b)
34 {
35  int r;
36  __asm__ ("smmul %0, %1, %2" : "=r"(r) : "r"(a), "r"(b));
37  return r;
38 }
39 
40 #define FASTDIV FASTDIV
41 static av_always_inline av_const int FASTDIV(int a, int b)
42 {
43  int r;
44  __asm__ ("cmp %2, #2 \n\t"
45  "ldr %0, [%3, %2, lsl #2] \n\t"
46  "ite le \n\t"
47  "lsrle %0, %1, #1 \n\t"
48  "smmulgt %0, %0, %1 \n\t"
49  : "=&r"(r) : "r"(a), "r"(b), "r"(ff_inverse) : "cc");
50  return r;
51 }
52 
53 #else /* HAVE_ARMV6_INLINE */
54 
55 #define FASTDIV FASTDIV
56 static av_always_inline av_const int FASTDIV(int a, int b)
57 {
58  int r, t;
59  __asm__ ("umull %1, %0, %2, %3"
60  : "=&r"(r), "=&r"(t) : "r"(a), "r"(ff_inverse[b]));
61  return r;
62 }
63 #endif
64 
65 #define MLS64(d, a, b) MAC64(d, -(a), b)
66 
67 #if HAVE_ARMV5TE_INLINE
68 
69 /* signed 16x16 -> 32 multiply add accumulate */
70 # define MAC16(rt, ra, rb) \
71  __asm__ ("smlabb %0, %1, %2, %0" : "+r"(rt) : "r"(ra), "r"(rb));
72 
73 /* signed 16x16 -> 32 multiply */
74 # define MUL16 MUL16
75 static inline av_const int MUL16(int ra, int rb)
76 {
77  int rt;
78  __asm__ ("smulbb %0, %1, %2" : "=r"(rt) : "r"(ra), "r"(rb));
79  return rt;
80 }
81 
82 #endif
83 
84 #define mid_pred mid_pred
85 static inline av_const int mid_pred(int a, int b, int c)
86 {
87  int m;
88  __asm__ (
89  "mov %0, %2 \n\t"
90  "cmp %1, %2 \n\t"
91  "itt gt \n\t"
92  "movgt %0, %1 \n\t"
93  "movgt %1, %2 \n\t"
94  "cmp %1, %3 \n\t"
95  "it le \n\t"
96  "movle %1, %3 \n\t"
97  "cmp %0, %1 \n\t"
98  "it gt \n\t"
99  "movgt %0, %1 \n\t"
100  : "=&r"(m), "+r"(a)
101  : "r"(b), "r"(c)
102  : "cc");
103  return m;
104 }
105 
106 #endif /* HAVE_INLINE_ASM */
107 
108 #endif /* AVCODEC_ARM_MATHOPS_H */