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 <assert.h>
24 #include "softfloat.h"
25 #include "common.h"
26 #include "log.h"
27 
28 #undef printf
29 
30 int main(void){
31  SoftFloat one= av_int2sf(1, 0);
32  SoftFloat sf1, sf2;
33  double d1, d2;
34  int i, j;
36 
37  d1= 1;
38  for(i= 0; i<10; i++){
39  d1= 1/(d1+1);
40  }
41  printf("test1 double=%d\n", (int)(d1 * (1<<24)));
42 
43  sf1= one;
44  for(i= 0; i<10; i++){
45  sf1= av_div_sf(one, av_normalize_sf(av_add_sf(one, sf1)));
46  }
47  printf("test1 sf =%d\n", av_sf2int(sf1, 24));
48 
49 
50  for(i= 0; i<100; i++){
52  d1= i;
53  d2= i/100.0;
54  for(j= 0; j<1000; j++){
55  d1= (d1+1)*d2;
56  }
57  STOP_TIMER("float add mul")
58  }
59  printf("test2 double=%d\n", (int)(d1 * (1<<24)));
60 
61  for(i= 0; i<100; i++){
63  sf1= av_int2sf(i, 0);
64  sf2= av_div_sf(av_int2sf(i, 2), av_int2sf(200, 3));
65  for(j= 0; j<1000; j++){
66  sf1= av_mul_sf(av_add_sf(sf1, one),sf2);
67  }
68  STOP_TIMER("softfloat add mul")
69  }
70  printf("test2 sf =%d (%d %d)\n", av_sf2int(sf1, 24), sf1.exp, sf1.mant);
71  return 0;
72 }
static av_const SoftFloat av_div_sf(SoftFloat a, SoftFloat b)
b has to be normalized and not zero.
Definition: softfloat.h:89
int32_t mant
Definition: softfloat.h:33
static av_const SoftFloat av_normalize_sf(SoftFloat a)
Definition: softfloat.h:36
init variable d2
void av_log_set_level(int level)
Definition: log.c:269
static av_const int av_sf2int(SoftFloat v, int frac_bits)
Rounding is to -inf.
Definition: softfloat.h:120
#define START_TIMER
Definition: timer.h:74
synthesis window for stochastic i
int main(void)
Definition: softfloat.c:30
static av_const SoftFloat av_add_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:101
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:162
common internal and external API header
static av_const SoftFloat av_mul_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:79
int32_t exp
Definition: softfloat.h:32
#define STOP_TIMER(id)
Definition: timer.h:75
printf("static const uint8_t my_array[100] = {\n")
static av_const SoftFloat av_int2sf(int v, int frac_bits)
Definition: softfloat.h:113