Go to the documentation of this file.
1 /*
2  * Format Conversion Utils
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * MMX optimization by Nick Kurshev <nickols_k@mail.ru>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
25 #include "libavutil/attributes.h"
26 #include "libavutil/cpu.h"
27 #include "libavutil/x86/cpu.h"
28 #include "libavcodec/fmtconvert.h"
30 #if HAVE_X86ASM
32 void ff_int32_to_float_fmul_scalar_sse (float *dst, const int32_t *src, float mul, int len);
33 void ff_int32_to_float_fmul_scalar_sse2(float *dst, const int32_t *src, float mul, int len);
34 void ff_int32_to_float_fmul_array8_sse (FmtConvertContext *c, float *dst, const int32_t *src,
35  const float *mul, int len);
36 void ff_int32_to_float_fmul_array8_sse2(FmtConvertContext *c, float *dst, const int32_t *src,
37  const float *mul, int len);
39 #endif /* HAVE_X86ASM */
42 {
43 #if HAVE_X86ASM
46  if (EXTERNAL_SSE(cpu_flags)) {
47  c->int32_to_float_fmul_scalar = ff_int32_to_float_fmul_scalar_sse;
48  c->int32_to_float_fmul_array8 = ff_int32_to_float_fmul_array8_sse;
49  }
50  if (EXTERNAL_SSE2(cpu_flags)) {
51  c->int32_to_float_fmul_scalar = ff_int32_to_float_fmul_scalar_sse2;
52  c->int32_to_float_fmul_array8 = ff_int32_to_float_fmul_array8_sse2;
53  }
54 #endif /* HAVE_X86ASM */
55 }
static atomic_int cpu_flags
Definition: cpu.c:50
#define EXTERNAL_SSE(flags)
Definition: cpu.h:58
Macro definitions for various function/variable attributes.
#define av_cold
Definition: attributes.h:88
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
#define EXTERNAL_SSE2(flags)
Definition: cpu.h:59
void(* int32_to_float_fmul_array8)(struct FmtConvertContext *c, float *dst, const int32_t *src, const float *mul, int len)
Convert an array of int32_t to float and multiply by a float value from another array, stepping along the float array once for each 8 integers.
Definition: fmtconvert.h:63
#define src
Definition: vp8dsp.c:255
static float mul(float src0, float src1)
void(* int32_to_float_fmul_scalar)(float *dst, const int32_t *src, float mul, int len)
Convert an array of int32_t to float and multiply by a float value.
Definition: fmtconvert.h:38
main external API structure.
Definition: avcodec.h:531
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:95
int len
av_cold void ff_fmt_convert_init_x86(FmtConvertContext *c, AVCodecContext *avctx)