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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 
23 #include "libavutil/softfloat.h"
24 #include "libavutil/common.h"
25 #include "libavutil/log.h"
26 
27 #include <stdio.h>
28 
29 static const SoftFloat FLOAT_0_017776489257 = {0x1234, 12};
30 static const SoftFloat FLOAT_1374_40625 = {0xabcd, 25};
31 static const SoftFloat FLOAT_0_1249694824218 = {0xFFF, 15};
32 
33 
34 int main(void){
35  SoftFloat one= av_int2sf(1, 0);
36  SoftFloat sf1, sf2, sf3;
37  double d1, d2, d3;
38  int i, j;
40 
41  d1= 1;
42  for(i= 0; i<10; i++){
43  d1= 1/(d1+1);
44  }
45  printf("test1 double=%d\n", (int)(d1 * (1<<24)));
46 
47  sf1= one;
48  for(i= 0; i<10; i++){
49  sf1= av_div_sf(one, av_normalize_sf(av_add_sf(one, sf1)));
50  }
51  printf("test1 sf =%d\n", av_sf2int(sf1, 24));
52 
53 
54  for(i= 0; i<100; i++){
56  d1= i;
57  d2= i/100.0;
58  for(j= 0; j<1000; j++){
59  d1= (d1+1)*d2;
60  }
61  STOP_TIMER("float add mul")
62  }
63  printf("test2 double=%d\n", (int)(d1 * (1<<24)));
64 
65  for(i= 0; i<100; i++){
67  sf1= av_int2sf(i, 0);
68  sf2= av_div_sf(av_int2sf(i, 2), av_int2sf(200, 3));
69  for(j= 0; j<1000; j++){
70  sf1= av_mul_sf(av_add_sf(sf1, one),sf2);
71  }
72  STOP_TIMER("softfloat add mul")
73  }
74  printf("test2 sf =%d (%d %d)\n", av_sf2int(sf1, 24), sf1.exp, sf1.mant);
75 
76  d1 = 0.0177764893;
77  d2 = 1374.40625;
78  d3 = 0.1249694824;
79  d2 += d1;
80  d3 += d2;
81  printf("test3 double: %.10lf\n", d3);
82 
84  sf2 = FLOAT_1374_40625;
86  sf2 = av_add_sf(sf1, sf2);
87  sf3 = av_add_sf(sf3, sf2);
88  printf("test3 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf3), sf3.mant, sf3.exp);
89 
90  sf1 = av_int2sf(0xFFFFFFF0, 0);
91  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
92  sf1 = av_int2sf(0x00000010, 0);
93  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
94 
95  sf1 = av_int2sf(0x1FFFFFFF, 0);
96  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
97  sf1 = av_int2sf(0xE0000001, 0);
98  printf("test4 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
99 
100 
101  sf1 = (SoftFloat){ 0x20000000, MIN_EXP };
102  sf1 = av_mul_sf(sf1, sf1);
103  printf("test5 softfloat: %.10lf (0x%08x %d)\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp);
104 
105  sf1 = (SoftFloat){ 0x20000000, MIN_EXP };
106  sf2 = (SoftFloat){ 0x20000000, MAX_EXP };
107  i = av_cmp_sf(sf1, sf2);
108  j = av_cmp_sf(sf2, sf1);
109  sf1 = av_div_sf(sf1, sf2);
110  printf("test6 softfloat: %.10lf (0x%08x %d) %d %d\n", (double)av_sf2double(sf1), sf1.mant, sf1.exp, i, j);
111 
112  for(i= -50; i<50; i++) {
113  sf1= av_int2sf(i, 0);
114  for(j= -50; j<50; j++) {
115  int c;
116  sf2= av_int2sf(j, 0);
117  c = av_cmp_sf(sf1, sf2);
118  if (FFDIFFSIGN(i,j) != c && (FFDIFFSIGN(i,j)^c)<0) {
119  printf("av_cmp_sf failed at %d %d as %X\n", i, j, c);
120  }
121  c = av_gt_sf(sf1, sf2);
122  if ((i>j) != c) {
123  printf("av_gt_sf failed at %d %d as %X\n", i, j, c);
124  }
125  }
126  sf1 = av_int2sf(1, i);
127  for(j = -50; j < 50; j++) {
128  int c;
129  sf2 = av_int2sf(1, j);
130  c = av_cmp_sf(sf2, sf1);
131  if (FFDIFFSIGN(i,j) != c && (FFDIFFSIGN(i,j)^c) < 0) {
132  printf("av_cmp_sf failed2 at %d %d as %X\n", i, j, c);
133  }
134  c = av_gt_sf(sf1, sf2);
135  if ((i<j) != c) {
136  printf("av_gt_sf failed2 at %d %d as %X\n", i, j, c);
137  }
138  }
139  }
140 
141 
142  for(i= 0; i<4*36; i++){
143  int s, c;
144  double errs, errc;
145 
146  av_sincos_sf(i*(1ULL<<32)/36/4, &s, &c);
147  errs = (double)s/ (1<<30) - sin(i*M_PI/36);
148  errc = (double)c/ (1<<30) - cos(i*M_PI/36);
149  if (fabs(errs) > 0.00000002 || fabs(errc) >0.001) {
150  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));
151  }
152 
153  }
154  return 0;
155 
156 }
const char * s
Definition: avisynth_c.h:768
static const SoftFloat FLOAT_1374_40625
Definition: softfloat.c:30
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:116
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
static av_const SoftFloat av_normalize_sf(SoftFloat a)
Definition: softfloat.h:57
static const SoftFloat FLOAT_0_017776489257
Definition: softfloat.c:29
#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:231
#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:131
static av_const int av_gt_sf(SoftFloat a, SoftFloat b)
Compares two SoftFloats.
Definition: softfloat.h:143
static av_const int av_sf2int(SoftFloat v, int frac_bits)
Converts a SoftFloat to an integer.
Definition: softfloat.h:189
#define START_TIMER
Definition: timer.h:94
int main(void)
Definition: softfloat.c:34
#define MIN_EXP
Definition: softfloat.h:30
static av_const SoftFloat av_add_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:155
common internal and external API header
static av_const SoftFloat av_mul_sf(SoftFloat a, SoftFloat b)
Definition: softfloat.h:102
int32_t exp
Definition: softfloat.h:36
#define STOP_TIMER(id)
Definition: timer.h:95
static AVCodec * c
#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:176
#define M_PI
Definition: mathematics.h:52
static const SoftFloat FLOAT_0_1249694824218
Definition: softfloat.c:31