FFmpeg
intreadwrite.h
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1 /*
2  * Copyright (c) 2010 Alexander Strange <astrange@ithinksw.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_X86_INTREADWRITE_H
22 #define AVUTIL_X86_INTREADWRITE_H
23 
24 #include <stdint.h>
25 #include "config.h"
26 #include "libavutil/attributes.h"
27 
28 #if HAVE_MMX
29 
30 #if !HAVE_FAST_64BIT && defined(__MMX__)
31 
32 #define AV_COPY64 AV_COPY64
33 static av_always_inline void AV_COPY64(void *d, const void *s)
34 {
35  __asm__("movq %1, %%mm0 \n\t"
36  "movq %%mm0, %0 \n\t"
37  : "=m"(*(uint64_t*)d)
38  : "m" (*(const uint64_t*)s)
39  : "mm0");
40 }
41 
42 #define AV_SWAP64 AV_SWAP64
43 static av_always_inline void AV_SWAP64(void *a, void *b)
44 {
45  __asm__("movq %1, %%mm0 \n\t"
46  "movq %0, %%mm1 \n\t"
47  "movq %%mm0, %0 \n\t"
48  "movq %%mm1, %1 \n\t"
49  : "+m"(*(uint64_t*)a), "+m"(*(uint64_t*)b)
50  ::"mm0", "mm1");
51 }
52 
53 #define AV_ZERO64 AV_ZERO64
54 static av_always_inline void AV_ZERO64(void *d)
55 {
56  __asm__("pxor %%mm0, %%mm0 \n\t"
57  "movq %%mm0, %0 \n\t"
58  : "=m"(*(uint64_t*)d)
59  :: "mm0");
60 }
61 
62 #endif /* !HAVE_FAST_64BIT && defined(__MMX__) */
63 
64 #ifdef __SSE__
65 
66 #define AV_COPY128 AV_COPY128
67 static av_always_inline void AV_COPY128(void *d, const void *s)
68 {
69  struct v {uint64_t v[2];};
70 
71  __asm__("movaps %1, %%xmm0 \n\t"
72  "movaps %%xmm0, %0 \n\t"
73  : "=m"(*(struct v*)d)
74  : "m" (*(const struct v*)s)
75  : "xmm0");
76 }
77 
78 #endif /* __SSE__ */
79 
80 #ifdef __SSE2__
81 
82 #define AV_ZERO128 AV_ZERO128
83 static av_always_inline void AV_ZERO128(void *d)
84 {
85  struct v {uint64_t v[2];};
86 
87  __asm__("pxor %%xmm0, %%xmm0 \n\t"
88  "movdqa %%xmm0, %0 \n\t"
89  : "=m"(*(struct v*)d)
90  :: "xmm0");
91 }
92 
93 #endif /* __SSE2__ */
94 
95 #endif /* HAVE_MMX */
96 
97 #endif /* AVUTIL_X86_INTREADWRITE_H */
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
Macro definitions for various function/variable attributes.
#define AV_COPY64(d, s)
Definition: intreadwrite.h:605
#define b
Definition: input.c:41
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_ZERO128(d)
Definition: intreadwrite.h:637
#define AV_SWAP64(a, b)
Definition: intreadwrite.h:619
#define AV_ZERO64(d)
Definition: intreadwrite.h:633
#define AV_COPY128(d, s)
Definition: intreadwrite.h:609
#define av_always_inline
Definition: attributes.h:39