FFmpeg
bswapdsp.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include <stdint.h>
20 
21 #include "libavutil/attributes.h"
22 #include "libavutil/bswap.h"
23 #include "bswapdsp.h"
24 
25 static void bswap_buf(uint32_t *dst, const uint32_t *src, int w)
26 {
27  int i;
28 
29  for (i = 0; i + 8 <= w; i += 8) {
30  dst[i + 0] = av_bswap32(src[i + 0]);
31  dst[i + 1] = av_bswap32(src[i + 1]);
32  dst[i + 2] = av_bswap32(src[i + 2]);
33  dst[i + 3] = av_bswap32(src[i + 3]);
34  dst[i + 4] = av_bswap32(src[i + 4]);
35  dst[i + 5] = av_bswap32(src[i + 5]);
36  dst[i + 6] = av_bswap32(src[i + 6]);
37  dst[i + 7] = av_bswap32(src[i + 7]);
38  }
39  for (; i < w; i++)
40  dst[i + 0] = av_bswap32(src[i + 0]);
41 }
42 
43 static void bswap16_buf(uint16_t *dst, const uint16_t *src, int len)
44 {
45  while (len--)
46  *dst++ = av_bswap16(*src++);
47 }
48 
50 {
51  c->bswap_buf = bswap_buf;
53 
54  if (ARCH_X86)
56 }
static void bswap16_buf(uint16_t *dst, const uint16_t *src, int len)
Definition: bswapdsp.c:43
void(* bswap16_buf)(uint16_t *dst, const uint16_t *src, int len)
Definition: bswapdsp.h:26
#define av_bswap16
Definition: bswap.h:31
#define src
Definition: vp8dsp.c:254
Macro definitions for various function/variable attributes.
#define av_cold
Definition: attributes.h:82
void(* bswap_buf)(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.h:25
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
void ff_bswapdsp_init_x86(BswapDSPContext *c)
Definition: bswapdsp_init.c:30
uint8_t w
Definition: llviddspenc.c:38
#define av_bswap32
Definition: bswap.h:33
byte swapping routines
static void bswap_buf(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.c:25
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
int len