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
37static void
38err_exit(const char *msg)
39{
40    fprintf(stderr, "%s\n", msg);
41    exit(1);
42}
43
44static mpd_t *
45new_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 */
64static int
65color_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
113int
114main(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}
194