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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 "libavutil/timer.h"
22 
23 #include <inttypes.h>
24 
25 #include "libavutil/softfloat.h"
26 #include "libavutil/common.h"
27 #include "libavutil/log.h"
28 
29 #include <stdio.h>
30 
31 static const SoftFloat FLOAT_0_017776489257 = {0x1234, 12};
32 static const SoftFloat FLOAT_1374_40625 = {0xabcd, 25};
33 static const SoftFloat FLOAT_0_1249694824218 = {0xFFF, 15};
34 
35 
36 int main(void){
37  SoftFloat one= av_int2sf(1, 0);
38  SoftFloat sf1, sf2, sf3;
39  double d1, d2, d3;
40  int i, j;
42 
43  d1= 1;
44  for(i= 0; i<10; i++){
45  d1= 1/(d1+1);
46  }
47  printf("test1 double=%d\n", (int)(d1 * (1<<24)));
48 
49  sf1= one;
50  for(i= 0; i<10; i++){
51  sf1= av_div_sf(one, av_normalize_sf(av_add_sf(one, sf1)));
52  }
53  printf("test1 sf =%d\n", av_sf2int(sf1, 24));
54 
55 
56  for(i= 0; i<100; i++){
58  d1= i;
59  d2= i/100.0;
60  for(j= 0; j<1000; j++){
61  d1= (d1+1)*d2;
62  }
63  STOP_TIMER("float add mul")
64  }
65  printf("test2 double=%d\n", (int)(d1 * (1<<24)));
66 
67  for(i= 0; i<100; i++){
69  sf1= av_int2sf(i, 0);
70  sf2= av_div_sf(av_int2sf(i, 2), av_int2sf(200, 3));
71  for(j= 0; j<1000; j++){
72  sf1= av_mul_sf(av_add_sf(sf1, one),sf2);
73  }
74  STOP_TIMER("softfloat add mul")
75  }
76  printf("test2 sf =%d (%d %d)\n", av_sf2int(sf1, 24), sf1.exp, sf1.mant);
77 
78  d1 = 0.0177764893;
79  d2 = 1374.40625;
80  d3 = 0.1249694824;
81  d2 += d1;
82  d3 += d2;
83  printf("test3 double: %.10lf\n", d3);
84 
86  sf2 = FLOAT_1374_40625;
88  sf2 = av_add_sf(sf1, sf2);
89  sf3 = av_add_sf(sf3, sf2);
90  printf("test3 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf3), sf3.mant, sf3.exp);
91 
92  sf1 = av_int2sf(0xFFFFFFF0, 0);
93  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
94  sf1 = av_int2sf(0x00000010, 0);
95  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
96 
97  sf1 = av_int2sf(0x1FFFFFFF, 0);
98  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
99  sf1 = av_int2sf(0xE0000001, 0);
100  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
101 
102 
103  sf1 = (SoftFloat){ 0x20000000, MIN_EXP };
104  sf1 = av_mul_sf(sf1, sf1);
105  printf("test5 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
106 
107  sf1 = (SoftFloat){ 0x20000000, MIN_EXP };
108  sf2 = (SoftFloat){ 0x20000000, MAX_EXP };
109  i = av_cmp_sf(sf1, sf2);
110  j = av_cmp_sf(sf2, sf1);
111  sf1 = av_div_sf(sf1, sf2);
112  printf("test6 softfloat: %.10lf (0x%08x %d) %d %d\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp, i, j);
113 
114  for(i= -50; i<50; i++) {
115  sf1= av_int2sf(i, 0);
116  for(j= -50; j<50; j++) {
117  int c;
118  sf2= av_int2sf(j, 0);
119  c = av_cmp_sf(sf1, sf2);
120  if (FFDIFFSIGN(i,j) != c && (FFDIFFSIGN(i,j)^c)<0) {
121  printf("av_cmp_sf failed at %d %d as %X\n", i, j, c);
122  }
123  c = av_gt_sf(sf1, sf2);
124  if ((i>j) != c) {
125  printf("av_gt_sf failed at %d %d as %X\n", i, j, c);
126  }
127  }
128  sf1 = av_int2sf(1, i);
129  for(j = -50; j < 50; j++) {
130  int c;
131  sf2 = av_int2sf(1, j);
132  c = av_cmp_sf(sf2, sf1);
133  if (FFDIFFSIGN(i,j) != c && (FFDIFFSIGN(i,j)^c) < 0) {
134  printf("av_cmp_sf failed2 at %d %d as %X\n", i, j, c);
135  }
136  c = av_gt_sf(sf1, sf2);
137  if ((i<j) != c) {
138  printf("av_gt_sf failed2 at %d %d as %X\n", i, j, c);
139  }
140  }
141  }
142 
143 
144  for(i= 0; i<4*36; i++){
145  int s, c;
146  double errs, errc;
147 
148  av_sincos_sf(i*(1ULL<<32)/36/4, &s, &c);
149  errs = (double)s/ (1<<30) - sin(i*M_PI/36);
150  errc = (double)c/ (1<<30) - cos(i*M_PI/36);
151  if (fabs(errs) > 0.00000002 || fabs(errc) >0.001) {
152  printf("sincos FAIL %d %f %f %f %f\n", i, (float)s/ (1<<30), (float)c/ (1<<30), sin(i*M_PI/36), cos(i*M_PI/36));
153  }
154 
155  }
156  return 0;
157 
158 }
const char * s
Definition: avisynth_c.h:768
static const SoftFloat FLOAT_1374_40625
Definition: softfloat.c:32
void av_log_set_level(int level)
Set the log level.
Definition: log.c:391
static av_const SoftFloat av_div_sf(SoftFloat a, SoftFloat b)
b has to be normalized and not zero.
Definition: softfloat.h:115
static av_const double av_sf2double(SoftFloat v)
Convert a SoftFloat to a double precision float.
Definition: softfloat.h:51
int32_t mant
Definition: softfloat.h:35
high precision timer, useful to profile code
static av_const SoftFloat av_normalize_sf(SoftFloat a)
Definition: softfloat.h:56
static const SoftFloat FLOAT_0_017776489257
Definition: softfloat.c:31
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
static av_unused void av_sincos_sf(int a, int *s, int *c)
Rounding-to-nearest used.
Definition: softfloat.h:239
#define FFDIFFSIGN(x, y)
Comparator.
Definition: common.h:92
static av_const int av_cmp_sf(SoftFloat a, SoftFloat b)
Compares two SoftFloats.
Definition: softfloat.h:137
static av_const int av_gt_sf(SoftFloat a, SoftFloat b)
Compares two SoftFloats.
Definition: softfloat.h:149
static av_const int av_sf2int(SoftFloat v, int frac_bits)
Converts a SoftFloat to an integer.
Definition: softfloat.h:197
#define START_TIMER
Definition: timer.h:137
int main(void)
Definition: softfloat.c:36
#define MIN_EXP
Definition: softfloat.h:30
static av_const SoftFloat av_add_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:161
common internal and external API header
static av_const SoftFloat av_mul_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:101
static double c[64]
int32_t exp
Definition: softfloat.h:36
#define STOP_TIMER(id)
Definition: timer.h:138
#define MAX_EXP
Definition: softfloat.h:31
static av_const SoftFloat av_int2sf(int v, int frac_bits)
Converts a mantisse and exponent to a SoftFloat.
Definition: softfloat.h:184
#define M_PI
Definition: mathematics.h:52
static const SoftFloat FLOAT_0_1249694824218
Definition: softfloat.c:33