1 /*
2 * Copyright (c) 2008-2020 Stefan Krah. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28
29 #include "mpdecimal.h"
30
31 #include <stdint.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <time.h>
35
36
37 static void
38 err_exit(const char *msg)
39 {
40 fprintf(stderr, "%s\n", msg);
41 exit(1);
42 }
43
44 static mpd_t *
45 new_mpd(void)
46 {
47 mpd_t *x = mpd_qnew();
48 if (x == NULL) {
49 err_exit("out of memory");
50 }
51
52 return x;
53 }
54
55 /*
56 * Example from: http://en.wikipedia.org/wiki/Mandelbrot_set
57 *
58 * Escape time algorithm for drawing the set:
59 *
60 * Point x0, y0 is deemed to be in the Mandelbrot set if the return
61 * value is maxiter. Lower return values indicate how quickly points
62 * escaped and can be used for coloring.
63 */
64 static int
65 color_point(const mpd_t *x0, const mpd_t *y0, const long maxiter, mpd_context_t *ctx)
66 {
67 mpd_t *x, *y, *sq_x, *sq_y;
68 mpd_t *two, *four, *c;
69 long i;
70
71 x = new_mpd();
72 y = new_mpd();
73 mpd_set_u32(x, 0, ctx);
74 mpd_set_u32(y, 0, ctx);
75
76 sq_x = new_mpd();
77 sq_y = new_mpd();
78 mpd_set_u32(sq_x, 0, ctx);
79 mpd_set_u32(sq_y, 0, ctx);
80
81 two = new_mpd();
82 four = new_mpd();
83 mpd_set_u32(two, 2, ctx);
84 mpd_set_u32(four, 4, ctx);
85
86 c = new_mpd();
87 mpd_set_u32(c, 0, ctx);
88
89 for (i = 0; i < maxiter && mpd_cmp(c, four, ctx) <= 0; i++) {
90 mpd_mul(y, x, y, ctx);
91 mpd_mul(y, y, two, ctx);
92 mpd_add(y, y, y0, ctx);
93
94 mpd_sub(x, sq_x, sq_y, ctx);
95 mpd_add(x, x, x0, ctx);
96
97 mpd_mul(sq_x, x, x, ctx);
98 mpd_mul(sq_y, y, y, ctx);
99 mpd_add(c, sq_x, sq_y, ctx);
100 }
101
102 mpd_del(c);
103 mpd_del(four);
104 mpd_del(two);
105 mpd_del(sq_y);
106 mpd_del(sq_x);
107 mpd_del(y);
108 mpd_del(x);
109
110 return i;
111 }
112
113 int
114 main(int argc, char **argv)
115 {
116 mpd_context_t ctx;
117 mpd_t *x0, *y0;
118 mpd_t *sqrt_2, *xstep, *ystep;
119 mpd_ssize_t prec = 19;
120
121 long iter = 1000;
122 int points[40][80];
123 int i, j;
124 clock_t start_clock, end_clock;
125
126
127 if (argc != 3) {
128 fprintf(stderr, "usage: ./bench prec iter\n");
129 exit(1);
130 }
131 prec = strtoll(argv[1], NULL, 10);
132 iter = strtol(argv[2], NULL, 10);
133
134 mpd_init(&ctx, prec);
135 /* no more MPD_MINALLOC changes after here */
136
137 sqrt_2 = new_mpd();
138 xstep = new_mpd();
139 ystep = new_mpd();
140 x0 = new_mpd();
141 y0 = new_mpd();
142
143 mpd_set_u32(sqrt_2, 2, &ctx);
144 mpd_sqrt(sqrt_2, sqrt_2, &ctx);
145 mpd_div_u32(xstep, sqrt_2, 40, &ctx);
146 mpd_div_u32(ystep, sqrt_2, 20, &ctx);
147
148 start_clock = clock();
149 mpd_copy(y0, sqrt_2, &ctx);
150 for (i = 0; i < 40; i++) {
151 mpd_copy(x0, sqrt_2, &ctx);
152 mpd_set_negative(x0);
153 for (j = 0; j < 80; j++) {
154 points[i][j] = color_point(x0, y0, iter, &ctx);
155 mpd_add(x0, x0, xstep, &ctx);
156 }
157 mpd_sub(y0, y0, ystep, &ctx);
158 }
159 end_clock = clock();
160
161 #ifdef BENCH_VERBOSE
162 for (i = 0; i < 40; i++) {
163 for (j = 0; j < 80; j++) {
164 if (points[i][j] == iter) {
165 putchar('*');
166 }
167 else if (points[i][j] >= 10) {
168 putchar('+');
169 }
170 else if (points[i][j] >= 5) {
171 putchar('.');
172 }
173 else {
174 putchar(' ');
175 }
176 }
177 putchar('\n');
178 }
179 putchar('\n');
180 #else
181 (void)points; /* suppress gcc warning */
182 #endif
183
184 printf("time: %f\n\n", (double)(end_clock-start_clock)/(double)CLOCKS_PER_SEC);
185
186 mpd_del(y0);
187 mpd_del(x0);
188 mpd_del(ystep);
189 mpd_del(xstep);
190 mpd_del(sqrt_2);
191
192 return 0;
193 }