FFmpeg  4.0
timer.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
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_TIMER_H
22 #define AVUTIL_X86_TIMER_H
23 
24 #include <stdint.h>
25 
26 #if HAVE_INLINE_ASM
27 
28 #define FF_TIMER_UNITS "decicycles"
29 #define AV_READ_TIME read_time
30 
31 static inline uint64_t read_time(void)
32 {
33  uint32_t a, d;
34  __asm__ volatile(
35 #if ARCH_X86_64 || defined(__SSE2__)
36  "lfence \n\t"
37 #endif
38  "rdtsc \n\t"
39  : "=a" (a), "=d" (d));
40  return ((uint64_t)d << 32) + a;
41 }
42 
43 #elif HAVE_RDTSC
44 
45 #include <intrin.h>
46 #define AV_READ_TIME __rdtsc
47 
48 #endif /* HAVE_INLINE_ASM */
49 
50 #endif /* AVUTIL_X86_TIMER_H */
static uint64_t read_time(void)
Definition: timer.h:28