FFmpeg
cpu.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 <stdio.h>
20 
21 #include "config.h"
22 
23 #include "libavutil/cpu.h"
24 #include "libavutil/avstring.h"
25 
26 #if HAVE_UNISTD_H
27 #include <unistd.h>
28 #endif
29 #if !HAVE_GETOPT
30 #include "compat/getopt.c"
31 #endif
32 
33 static const struct {
34  int flag;
35  const char *name;
36 } cpu_flag_tab[] = {
37 #if ARCH_AARCH64
38  { AV_CPU_FLAG_ARMV8, "armv8" },
39  { AV_CPU_FLAG_NEON, "neon" },
40  { AV_CPU_FLAG_VFP, "vfp" },
41 #elif ARCH_ARM
42  { AV_CPU_FLAG_ARMV5TE, "armv5te" },
43  { AV_CPU_FLAG_ARMV6, "armv6" },
44  { AV_CPU_FLAG_ARMV6T2, "armv6t2" },
45  { AV_CPU_FLAG_VFP, "vfp" },
46  { AV_CPU_FLAG_VFP_VM, "vfp_vm" },
47  { AV_CPU_FLAG_VFPV3, "vfpv3" },
48  { AV_CPU_FLAG_NEON, "neon" },
49  { AV_CPU_FLAG_SETEND, "setend" },
50 #elif ARCH_PPC
51  { AV_CPU_FLAG_ALTIVEC, "altivec" },
52 #elif ARCH_X86
53  { AV_CPU_FLAG_MMX, "mmx" },
54  { AV_CPU_FLAG_MMXEXT, "mmxext" },
55  { AV_CPU_FLAG_SSE, "sse" },
56  { AV_CPU_FLAG_SSE2, "sse2" },
57  { AV_CPU_FLAG_SSE2SLOW, "sse2slow" },
58  { AV_CPU_FLAG_SSE3, "sse3" },
59  { AV_CPU_FLAG_SSE3SLOW, "sse3slow" },
60  { AV_CPU_FLAG_SSSE3, "ssse3" },
61  { AV_CPU_FLAG_ATOM, "atom" },
62  { AV_CPU_FLAG_SSE4, "sse4.1" },
63  { AV_CPU_FLAG_SSE42, "sse4.2" },
64  { AV_CPU_FLAG_AVX, "avx" },
65  { AV_CPU_FLAG_AVXSLOW, "avxslow" },
66  { AV_CPU_FLAG_XOP, "xop" },
67  { AV_CPU_FLAG_FMA3, "fma3" },
68  { AV_CPU_FLAG_FMA4, "fma4" },
69  { AV_CPU_FLAG_3DNOW, "3dnow" },
70  { AV_CPU_FLAG_3DNOWEXT, "3dnowext" },
71  { AV_CPU_FLAG_CMOV, "cmov" },
72  { AV_CPU_FLAG_AVX2, "avx2" },
73  { AV_CPU_FLAG_BMI1, "bmi1" },
74  { AV_CPU_FLAG_BMI2, "bmi2" },
75  { AV_CPU_FLAG_AESNI, "aesni" },
76  { AV_CPU_FLAG_AVX512, "avx512" },
77 #endif
78  { 0 }
79 };
80 
81 static void print_cpu_flags(int cpu_flags, const char *type)
82 {
83  int i;
84 
85  printf("cpu_flags(%s) = 0x%08X\n", type, cpu_flags);
86  printf("cpu_flags_str(%s) =", type);
87  for (i = 0; cpu_flag_tab[i].flag; i++)
88  if (cpu_flags & cpu_flag_tab[i].flag)
89  printf(" %s", cpu_flag_tab[i].name);
90  printf("\n");
91 }
92 
93 
94 int main(int argc, char **argv)
95 {
96  int cpu_flags_raw = av_get_cpu_flags();
97  int cpu_flags_eff;
98  int cpu_count = av_cpu_count();
99  char threads[5] = "auto";
100  int i;
101 
102  for(i = 0; cpu_flag_tab[i].flag; i++) {
103  unsigned tmp = 0;
104  if (av_parse_cpu_caps(&tmp, cpu_flag_tab[i].name) < 0) {
105  fprintf(stderr, "Table missing %s\n", cpu_flag_tab[i].name);
106  return 4;
107  }
108  }
109 
110  if (cpu_flags_raw < 0)
111  return 1;
112 
113  for (;;) {
114  int c = getopt(argc, argv, "c:t:");
115  if (c == -1)
116  break;
117  switch (c) {
118  case 'c':
119  {
120  unsigned flags = av_get_cpu_flags();
121  if (av_parse_cpu_caps(&flags, optarg) < 0)
122  return 2;
123 
124  av_force_cpu_flags(flags);
125  break;
126  }
127  case 't':
128  {
129  int len = av_strlcpy(threads, optarg, sizeof(threads));
130  if (len >= sizeof(threads)) {
131  fprintf(stderr, "Invalid thread count '%s'\n", optarg);
132  return 2;
133  }
134  }
135  }
136  }
137 
138  cpu_flags_eff = av_get_cpu_flags();
139 
140  if (cpu_flags_eff < 0)
141  return 3;
142 
143  print_cpu_flags(cpu_flags_raw, "raw");
144  print_cpu_flags(cpu_flags_eff, "effective");
145  printf("threads = %s (cpu_count = %d)\n", threads, cpu_count);
146 
147  return 0;
148 }
AV_CPU_FLAG_VFP
#define AV_CPU_FLAG_VFP
Definition: cpu.h:67
av_force_cpu_flags
void av_force_cpu_flags(int arg)
Disables cpu detection and forces the specified flags.
Definition: cpu.c:65
AV_CPU_FLAG_SSE3
#define AV_CPU_FLAG_SSE3
Prescott SSE3 functions.
Definition: cpu.h:40
AV_CPU_FLAG_SSE3SLOW
#define AV_CPU_FLAG_SSE3SLOW
SSE3 supported, but usually not faster.
Definition: cpu.h:41
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
AV_CPU_FLAG_3DNOW
#define AV_CPU_FLAG_3DNOW
AMD 3DNOW.
Definition: cpu.h:34
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:93
AV_CPU_FLAG_BMI1
#define AV_CPU_FLAG_BMI1
Bit Manipulation Instruction Set 1.
Definition: cpu.h:56
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:50
name
const char * name
Definition: cpu.c:35
AV_CPU_FLAG_SSSE3
#define AV_CPU_FLAG_SSSE3
Conroe SSSE3 functions.
Definition: cpu.h:43
AV_CPU_FLAG_XOP
#define AV_CPU_FLAG_XOP
Bulldozer XOP functions.
Definition: cpu.h:51
av_parse_cpu_caps
int av_parse_cpu_caps(unsigned *flags, const char *s)
Parse CPU caps from a string and update the given AV_CPU_* flags based on that.
Definition: cpu.c:191
AV_CPU_FLAG_3DNOWEXT
#define AV_CPU_FLAG_3DNOWEXT
AMD 3DNowExt.
Definition: cpu.h:39
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AV_CPU_FLAG_AVX512
#define AV_CPU_FLAG_AVX512
AVX-512 functions: requires OS support even if YMM/ZMM registers aren't used.
Definition: cpu.h:58
getopt
static int getopt(int argc, char *argv[], char *opts)
Definition: getopt.c:41
AV_CPU_FLAG_ARMV6
#define AV_CPU_FLAG_ARMV6
Definition: cpu.h:65
AV_CPU_FLAG_SSE4
#define AV_CPU_FLAG_SSE4
Penryn SSE4.1 functions.
Definition: cpu.h:46
print_cpu_flags
static void print_cpu_flags(int cpu_flags, const char *type)
Definition: cpu.c:81
flag
int flag
Definition: cpu.c:34
AV_CPU_FLAG_CMOV
#define AV_CPU_FLAG_CMOV
supports cmov instruction
Definition: cpu.h:53
AV_CPU_FLAG_ALTIVEC
#define AV_CPU_FLAG_ALTIVEC
standard
Definition: cpu.h:60
c
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
av_cpu_count
int av_cpu_count(void)
Definition: cpu.c:267
AV_CPU_FLAG_SSE2
#define AV_CPU_FLAG_SSE2
PIV SSE2 functions.
Definition: cpu.h:36
AV_CPU_FLAG_SETEND
#define AV_CPU_FLAG_SETEND
Definition: cpu.h:72
main
int main(int argc, char **argv)
Definition: cpu.c:94
AV_CPU_FLAG_AVXSLOW
#define AV_CPU_FLAG_AVXSLOW
AVX supported, but slow when using YMM registers (e.g. Bulldozer)
Definition: cpu.h:50
AV_CPU_FLAG_AVX
#define AV_CPU_FLAG_AVX
AVX functions: requires OS support even if YMM registers aren't used.
Definition: cpu.h:49
AV_CPU_FLAG_FMA4
#define AV_CPU_FLAG_FMA4
Bulldozer FMA4 functions.
Definition: cpu.h:52
cpu.h
AV_CPU_FLAG_AVX2
#define AV_CPU_FLAG_AVX2
AVX2 functions: requires OS support even if YMM registers aren't used.
Definition: cpu.h:54
cpu_flag_tab
static const struct @306 cpu_flag_tab[]
AV_CPU_FLAG_SSE2SLOW
#define AV_CPU_FLAG_SSE2SLOW
SSE2 supported, but usually not faster.
Definition: cpu.h:37
AV_CPU_FLAG_NEON
#define AV_CPU_FLAG_NEON
Definition: cpu.h:69
printf
printf("static const uint8_t my_array[100] = {\n")
AV_CPU_FLAG_FMA3
#define AV_CPU_FLAG_FMA3
Haswell FMA3 functions.
Definition: cpu.h:55
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AV_CPU_FLAG_SSE42
#define AV_CPU_FLAG_SSE42
Nehalem SSE4.2 functions.
Definition: cpu.h:47
AV_CPU_FLAG_ARMV8
#define AV_CPU_FLAG_ARMV8
Definition: cpu.h:70
len
int len
Definition: vorbis_enc_data.h:452
AV_CPU_FLAG_ATOM
#define AV_CPU_FLAG_ATOM
Atom processor, some SSSE3 instructions are slower.
Definition: cpu.h:45
AV_CPU_FLAG_VFPV3
#define AV_CPU_FLAG_VFPV3
Definition: cpu.h:68
getopt.c
AV_CPU_FLAG_ARMV5TE
#define AV_CPU_FLAG_ARMV5TE
Definition: cpu.h:64
AV_CPU_FLAG_MMX
#define AV_CPU_FLAG_MMX
standard MMX
Definition: cpu.h:31
AV_CPU_FLAG_AESNI
#define AV_CPU_FLAG_AESNI
Advanced Encryption Standard functions.
Definition: cpu.h:48
AV_CPU_FLAG_SSE
#define AV_CPU_FLAG_SSE
SSE functions.
Definition: cpu.h:35
AV_CPU_FLAG_MMXEXT
#define AV_CPU_FLAG_MMXEXT
SSE integer functions or AMD MMX ext.
Definition: cpu.h:32
optarg
static char * optarg
Definition: getopt.c:39
AV_CPU_FLAG_BMI2
#define AV_CPU_FLAG_BMI2
Bit Manipulation Instruction Set 2.
Definition: cpu.h:57
AV_CPU_FLAG_VFP_VM
#define AV_CPU_FLAG_VFP_VM
VFPv2 vector mode, deprecated in ARMv7-A and unavailable in various CPUs implementations.
Definition: cpu.h:71
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:565
av_strlcpy
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:83
avstring.h
AV_CPU_FLAG_ARMV6T2
#define AV_CPU_FLAG_ARMV6T2
Definition: cpu.h:66
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