matrix-test.c revision de17ff4a 
1/*
2 * Copyright © 2012 Siarhei Siamashka <siarhei.siamashka@gmail.com>
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24#include "utils.h"
25#include <assert.h>
26#include <stdlib.h>
27#include <stdio.h>
28#include <math.h>
29
30#ifdef HAVE_FLOAT128
31
32#define pixman_fixed_to_float128(x) (((__float128)(x)) / 65536.0Q)
33
34typedef struct { __float128 v[3]; } pixman_vector_f128_t;
35typedef struct { __float128 m[3][3]; } pixman_transform_f128_t;
36
37pixman_bool_t
38pixman_transform_point_f128 (const pixman_transform_f128_t *t,
39                             const pixman_vector_f128_t    *v,
40                             pixman_vector_f128_t          *result)
41{
42    int i;
43    for (i = 0; i < 3; i++)
44    {
45        result->v[i] = t->m[i][0] * v->v[0] +
46                       t->m[i][1] * v->v[1] +
47                       t->m[i][2] * v->v[2];
48    }
49    if (result->v[2] != 0)
50    {
51        result->v[0] /= result->v[2];
52        result->v[1] /= result->v[2];
53        result->v[2] = 1;
54        return TRUE;
55    }
56    else
57    {
58        return FALSE;
59    }
60}
61
62pixman_bool_t does_it_fit_fixed_48_16 (__float128 x)
63{
64    if (x >= 65536.0Q * 65536.0Q * 32768.0Q)
65        return FALSE;
66    if (x <= -65536.0Q * 65536.0Q * 32768.0Q)
67        return FALSE;
68    return TRUE;
69}
70
71#endif
72
73static inline uint32_t
74byteswap32 (uint32_t x)
75{
76    return ((x & ((uint32_t)0xFF << 24)) >> 24) |
77           ((x & ((uint32_t)0xFF << 16)) >>  8) |
78           ((x & ((uint32_t)0xFF <<  8)) <<  8) |
79           ((x & ((uint32_t)0xFF <<  0)) << 24);
80}
81
82static inline uint64_t
83byteswap64 (uint64_t x)
84{
85    return ((x & ((uint64_t)0xFF << 56)) >> 56) |
86           ((x & ((uint64_t)0xFF << 48)) >> 40) |
87           ((x & ((uint64_t)0xFF << 40)) >> 24) |
88           ((x & ((uint64_t)0xFF << 32)) >>  8) |
89           ((x & ((uint64_t)0xFF << 24)) <<  8) |
90           ((x & ((uint64_t)0xFF << 16)) << 24) |
91           ((x & ((uint64_t)0xFF <<  8)) << 40) |
92           ((x & ((uint64_t)0xFF <<  0)) << 56);
93}
94
95static void
96byteswap_transform (pixman_transform_t *t)
97{
98    int i, j;
99
100    if (is_little_endian ())
101        return;
102
103    for (i = 0; i < 3; i++)
104        for (j = 0; j < 3; j++)
105            t->matrix[i][j] = byteswap32 (t->matrix[i][j]);
106}
107
108static void
109byteswap_vector_48_16 (pixman_vector_48_16_t *v)
110{
111    int i;
112
113    if (is_little_endian ())
114        return;
115
116    for (i = 0; i < 3; i++)
117        v->v[i] = byteswap64 (v->v[i]);
118}
119
120uint32_t
121test_matrix (int testnum, int verbose)
122{
123    uint32_t crc32 = 0;
124    int i, j, k;
125    pixman_bool_t is_affine;
126
127    prng_srand (testnum);
128
129    for (i = 0; i < 100; i++)
130    {
131        pixman_bool_t           transform_ok;
132        pixman_transform_t      ti;
133        pixman_vector_48_16_t   vi, result_i;
134#ifdef HAVE_FLOAT128
135        pixman_transform_f128_t tf;
136        pixman_vector_f128_t    vf, result_f;
137#endif
138        prng_randmemset (&ti, sizeof(ti), 0);
139        prng_randmemset (&vi, sizeof(vi), 0);
140        byteswap_transform (&ti);
141        byteswap_vector_48_16 (&vi);
142
143        for (j = 0; j < 3; j++)
144        {
145            /* make sure that "vi" contains 31.16 fixed point data */
146            vi.v[j] >>= 17;
147            /* and apply random shift */
148            if (prng_rand_n (3) == 0)
149                vi.v[j] >>= prng_rand_n (46);
150        }
151
152        if (prng_rand_n (2))
153        {
154            /* random shift for the matrix */
155            for (j = 0; j < 3; j++)
156                for (k = 0; k < 3; k++)
157                    ti.matrix[j][k] >>= prng_rand_n (30);
158        }
159
160        if (prng_rand_n (2))
161        {
162            /* affine matrix */
163            ti.matrix[2][0] = 0;
164            ti.matrix[2][1] = 0;
165            ti.matrix[2][2] = pixman_fixed_1;
166        }
167
168        if (prng_rand_n (2))
169        {
170            /* cartesian coordinates */
171            vi.v[2] = pixman_fixed_1;
172        }
173
174        is_affine = (ti.matrix[2][0] == 0 && ti.matrix[2][1] == 0 &&
175                     ti.matrix[2][2] == pixman_fixed_1 &&
176                     vi.v[2] == pixman_fixed_1);
177
178        transform_ok = TRUE;
179        if (is_affine && prng_rand_n (2))
180            pixman_transform_point_31_16_affine (&ti, &vi, &result_i);
181        else
182            transform_ok = pixman_transform_point_31_16 (&ti, &vi, &result_i);
183
184#ifdef HAVE_FLOAT128
185        /* compare with a reference 128-bit floating point implementation */
186        for (j = 0; j < 3; j++)
187        {
188            vf.v[j] = pixman_fixed_to_float128 (vi.v[j]);
189            for (k = 0; k < 3; k++)
190            {
191                tf.m[j][k] = pixman_fixed_to_float128 (ti.matrix[j][k]);
192            }
193        }
194
195        if (pixman_transform_point_f128 (&tf, &vf, &result_f))
196        {
197            if (transform_ok ||
198                (does_it_fit_fixed_48_16 (result_f.v[0]) &&
199                 does_it_fit_fixed_48_16 (result_f.v[1]) &&
200                 does_it_fit_fixed_48_16 (result_f.v[2])))
201            {
202                for (j = 0; j < 3; j++)
203                {
204                    double diff = fabs (result_f.v[j] -
205                                        pixman_fixed_to_float128 (result_i.v[j]));
206
207                    if (is_affine && diff > (0.51 / 65536.0))
208                    {
209                        printf ("%d:%d: bad precision for affine (%.12f)\n",
210                               testnum, i, diff);
211                        abort ();
212                    }
213                    else if (diff > (0.71 / 65536.0))
214                    {
215                        printf ("%d:%d: bad precision for projective (%.12f)\n",
216                               testnum, i, diff);
217                        abort ();
218                    }
219                }
220            }
221        }
222#endif
223        byteswap_vector_48_16 (&result_i);
224        crc32 = compute_crc32 (crc32, &result_i, sizeof (result_i));
225    }
226    return crc32;
227}
228
229int
230main (int argc, const char *argv[])
231{
232    return fuzzer_test_main ("matrix", 20000,
233			     0xBEBF98C3,
234			     test_matrix, argc, argv);
235}
236