FFmpeg  2.6.3
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softfloat.c
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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 #include <inttypes.h>
22 #include <stdio.h>
23 #include "softfloat.h"
24 #include "common.h"
25 #include "log.h"
26 
27 #undef printf
28 
29 int main(void){
30  SoftFloat one= av_int2sf(1, 0);
31  SoftFloat sf1, sf2;
32  double d1, d2;
33  int i, j;
35 
36  d1= 1;
37  for(i= 0; i<10; i++){
38  d1= 1/(d1+1);
39  }
40  printf("test1 double=%d\n", (int)(d1 * (1<<24)));
41 
42  sf1= one;
43  for(i= 0; i<10; i++){
44  sf1= av_div_sf(one, av_normalize_sf(av_add_sf(one, sf1)));
45  }
46  printf("test1 sf =%d\n", av_sf2int(sf1, 24));
47 
48 
49  for(i= 0; i<100; i++){
51  d1= i;
52  d2= i/100.0;
53  for(j= 0; j<1000; j++){
54  d1= (d1+1)*d2;
55  }
56  STOP_TIMER("float add mul")
57  }
58  printf("test2 double=%d\n", (int)(d1 * (1<<24)));
59 
60  for(i= 0; i<100; i++){
62  sf1= av_int2sf(i, 0);
63  sf2= av_div_sf(av_int2sf(i, 2), av_int2sf(200, 3));
64  for(j= 0; j<1000; j++){
65  sf1= av_mul_sf(av_add_sf(sf1, one),sf2);
66  }
67  STOP_TIMER("softfloat add mul")
68  }
69  printf("test2 sf =%d (%d %d)\n", av_sf2int(sf1, 24), sf1.exp, sf1.mant);
70  return 0;
71 }
void av_log_set_level(int level)
Set the log level.
Definition: log.c:368
static av_const SoftFloat av_div_sf(SoftFloat a, SoftFloat b)
b has to be normalized and not zero.
Definition: softfloat.h:93
int32_t mant
Definition: softfloat.h:35
static av_const SoftFloat av_normalize_sf(SoftFloat a)
Definition: softfloat.h:38
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:196
static av_const int av_sf2int(SoftFloat v, int frac_bits)
Rounding is to -inf.
Definition: softfloat.h:126
#define START_TIMER
Definition: timer.h:86
int main(void)
Definition: softfloat.c:29
static av_const SoftFloat av_add_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:105
common internal and external API header
static av_const SoftFloat av_mul_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:82
int32_t exp
Definition: softfloat.h:34
#define STOP_TIMER(id)
Definition: timer.h:87
static av_const SoftFloat av_int2sf(int v, int frac_bits)
Definition: softfloat.h:119