FFmpeg
 All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
intreadwrite.h
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2009 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 AVUTIL_AVR32_INTREADWRITE_H
22 #define AVUTIL_AVR32_INTREADWRITE_H
23 
24 #include <stdint.h>
25 #include "config.h"
26 #include "libavutil/bswap.h"
27 
28 /*
29  * AVR32 does not support unaligned memory accesses, except for the AP
30  * series which suppports unaligned 32-bit loads and stores. 16-bit
31  * and 64-bit accesses must be aligned to 16 and 32 bits, respectively.
32  * This means we cannot use the byte-swapping load/store instructions
33  * here.
34  *
35  * For 16-bit, 24-bit, and (on UC series) 32-bit loads, we instead use
36  * the LDINS.B instruction, which gcc fails to utilise with the
37  * generic code. GCC also fails to use plain LD.W and ST.W even for
38  * AP processors, so we override the generic code. The 64-bit
39  * versions are improved by using our optimised 32-bit functions.
40  */
41 
42 #define AV_RL16 AV_RL16
43 static av_always_inline uint16_t AV_RL16(const void *p)
44 {
45  uint16_t v;
46  __asm__ ("ld.ub %0, %1 \n\t"
47  "ldins.b %0:l, %2 \n\t"
48  : "=&r"(v)
49  : "m"(*(const uint8_t*)p), "RKs12"(*((const uint8_t*)p+1)));
50  return v;
51 }
52 
53 #define AV_RB16 AV_RB16
54 static av_always_inline uint16_t AV_RB16(const void *p)
55 {
56  uint16_t v;
57  __asm__ ("ld.ub %0, %2 \n\t"
58  "ldins.b %0:l, %1 \n\t"
59  : "=&r"(v)
60  : "RKs12"(*(const uint8_t*)p), "m"(*((const uint8_t*)p+1)));
61  return v;
62 }
63 
64 #define AV_RB24 AV_RB24
65 static av_always_inline uint32_t AV_RB24(const void *p)
66 {
67  uint32_t v;
68  __asm__ ("ld.ub %0, %3 \n\t"
69  "ldins.b %0:l, %2 \n\t"
70  "ldins.b %0:u, %1 \n\t"
71  : "=&r"(v)
72  : "RKs12"(* (const uint8_t*)p),
73  "RKs12"(*((const uint8_t*)p+1)),
74  "m" (*((const uint8_t*)p+2)));
75  return v;
76 }
77 
78 #define AV_RL24 AV_RL24
79 static av_always_inline uint32_t AV_RL24(const void *p)
80 {
81  uint32_t v;
82  __asm__ ("ld.ub %0, %1 \n\t"
83  "ldins.b %0:l, %2 \n\t"
84  "ldins.b %0:u, %3 \n\t"
85  : "=&r"(v)
86  : "m" (* (const uint8_t*)p),
87  "RKs12"(*((const uint8_t*)p+1)),
88  "RKs12"(*((const uint8_t*)p+2)));
89  return v;
90 }
91 
92 #if ARCH_AVR32_AP
93 
94 #define AV_RB32 AV_RB32
95 static av_always_inline uint32_t AV_RB32(const void *p)
96 {
97  uint32_t v;
98  __asm__ ("ld.w %0, %1" : "=r"(v) : "m"(*(const uint32_t*)p));
99  return v;
100 }
101 
102 #define AV_WB32 AV_WB32
103 static av_always_inline void AV_WB32(void *p, uint32_t v)
104 {
105  __asm__ ("st.w %0, %1" : "=m"(*(uint32_t*)p) : "r"(v));
106 }
107 
108 /* These two would be defined by generic code, but we need them sooner. */
109 #define AV_RL32(p) av_bswap32(AV_RB32(p))
110 #define AV_WL32(p, v) AV_WB32(p, av_bswap32(v))
111 
112 #define AV_WB64 AV_WB64
113 static av_always_inline void AV_WB64(void *p, uint64_t v)
114 {
115  union { uint64_t v; uint32_t hl[2]; } vv = { v };
116  AV_WB32(p, vv.hl[0]);
117  AV_WB32((uint32_t*)p+1, vv.hl[1]);
118 }
119 
120 #define AV_WL64 AV_WL64
121 static av_always_inline void AV_WL64(void *p, uint64_t v)
122 {
123  union { uint64_t v; uint32_t hl[2]; } vv = { v };
124  AV_WL32(p, vv.hl[1]);
125  AV_WL32((uint32_t*)p+1, vv.hl[0]);
126 }
127 
128 #else /* ARCH_AVR32_AP */
129 
130 #define AV_RB32 AV_RB32
131 static av_always_inline uint32_t AV_RB32(const void *p)
132 {
133  uint32_t v;
134  __asm__ ("ld.ub %0, %4 \n\t"
135  "ldins.b %0:l, %3 \n\t"
136  "ldins.b %0:u, %2 \n\t"
137  "ldins.b %0:t, %1 \n\t"
138  : "=&r"(v)
139  : "RKs12"(* (const uint8_t*)p),
140  "RKs12"(*((const uint8_t*)p+1)),
141  "RKs12"(*((const uint8_t*)p+2)),
142  "m" (*((const uint8_t*)p+3)));
143  return v;
144 }
145 
146 #define AV_RL32 AV_RL32
147 static av_always_inline uint32_t AV_RL32(const void *p)
148 {
149  uint32_t v;
150  __asm__ ("ld.ub %0, %1 \n\t"
151  "ldins.b %0:l, %2 \n\t"
152  "ldins.b %0:u, %3 \n\t"
153  "ldins.b %0:t, %4 \n\t"
154  : "=&r"(v)
155  : "m" (* (const uint8_t*)p),
156  "RKs12"(*((const uint8_t*)p+1)),
157  "RKs12"(*((const uint8_t*)p+2)),
158  "RKs12"(*((const uint8_t*)p+3)));
159  return v;
160 }
161 
162 #endif /* ARCH_AVR32_AP */
163 
164 #define AV_RB64 AV_RB64
165 static av_always_inline uint64_t AV_RB64(const void *p)
166 {
167  union { uint64_t v; uint32_t hl[2]; } v;
168  v.hl[0] = AV_RB32(p);
169  v.hl[1] = AV_RB32((const uint32_t*)p+1);
170  return v.v;
171 }
172 
173 #define AV_RL64 AV_RL64
174 static av_always_inline uint64_t AV_RL64(const void *p)
175 {
176  union { uint64_t v; uint32_t hl[2]; } v;
177  v.hl[1] = AV_RL32(p);
178  v.hl[0] = AV_RL32((const uint32_t*)p+1);
179  return v.v;
180 }
181 
182 #endif /* AVUTIL_AVR32_INTREADWRITE_H */