1 /* Measure strncmp functions.
2 Copyright (C) 2013-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #define TEST_MAIN
20 #ifdef WIDE
21 # define TEST_NAME "wcsncmp"
22 #else
23 # define TEST_NAME "strncmp"
24 #endif
25 #include "bench-string.h"
26 #include "json-lib.h"
27
28 #ifdef WIDE
29 # define STRDUP wcsdup
30 #else
31 # define STRDUP strdup
32
33 int
34 generic_strncmp (const char *s1, const char *s2, size_t n);
35
36 IMPL (generic_strncmp, 0)
37
38 #endif
39
40 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
41
42 IMPL (STRNCMP, 1)
43
44 static void
45 do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s1, const CHAR
46 *s2, size_t n, int exp_result)
47 {
48 size_t i, iters = INNER_LOOP_ITERS;
49 timing_t start, stop, cur;
50
51 TIMING_NOW (start);
52 for (i = 0; i < iters; ++i)
53 {
54 CALL (impl, s1, s2, n);
55 }
56 TIMING_NOW (stop);
57
58 TIMING_DIFF (cur, start, stop);
59
60 json_element_double (json_ctx, (double) cur / (double) iters);
61 }
62
63 static void
64 do_test_limit (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
65 size_t n, int max_char, int exp_result)
66 {
67 size_t i, align_n;
68 CHAR *s1, *s2;
69
70 align1 &= 15;
71 align2 &= 15;
72 align_n = (page_size - n * CHARBYTES) & 15;
73
74 json_element_object_begin (json_ctx);
75 json_attr_uint (json_ctx, "strlen", (double) len);
76 json_attr_uint (json_ctx, "len", (double) n);
77 json_attr_uint (json_ctx, "align1", (double) align1);
78 json_attr_uint (json_ctx, "align2", (double) align2);
79 json_array_begin (json_ctx, "timings");
80
81 FOR_EACH_IMPL (impl, 0)
82 {
83 alloc_bufs ();
84 s1 = (CHAR *) (buf1 + page_size - n * CHARBYTES);
85 s2 = (CHAR *) (buf2 + page_size - n * CHARBYTES);
86
87 if (align1 < align_n)
88 s1 = (CHAR *) ((char *) s1 - (align_n - align1));
89
90 if (align2 < align_n)
91 s2 = (CHAR *) ((char *) s2 - (align_n - align2));
92
93 for (i = 0; i < n; i++)
94 s1[i] = s2[i] = 1 + 23 * i % max_char;
95
96 if (len < n)
97 {
98 s1[len] = 0;
99 s2[len] = 0;
100 if (exp_result < 0)
101 s2[len] = 32;
102 else if (exp_result > 0)
103 s1[len] = 64;
104 }
105
106 do_one_test (json_ctx, impl, s1, s2, n, exp_result);
107 }
108
109 json_array_end (json_ctx);
110 json_element_object_end (json_ctx);
111 }
112
113 static void
114 do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len, size_t
115 n, int max_char, int exp_result)
116 {
117 size_t i;
118 CHAR *s1, *s2;
119
120 if (n == 0)
121 return;
122
123 align1 &= getpagesize () - 1;
124 if (align1 + (n + 1) * CHARBYTES >= page_size)
125 return;
126
127 align2 &= getpagesize () - 1;
128 if (align2 + (n + 1) * CHARBYTES >= page_size)
129 return;
130
131 json_element_object_begin (json_ctx);
132 json_attr_uint (json_ctx, "strlen", (double)len);
133 json_attr_uint (json_ctx, "len", (double)n);
134 json_attr_uint (json_ctx, "align1", (double)align1);
135 json_attr_uint (json_ctx, "align2", (double)align2);
136 json_array_begin (json_ctx, "timings");
137
138 FOR_EACH_IMPL (impl, 0)
139 {
140 alloc_bufs ();
141 s1 = (CHAR *)(buf1 + align1);
142 s2 = (CHAR *)(buf2 + align2);
143
144 for (i = 0; i < n; i++)
145 s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % max_char;
146
147 s1[n] = 24 + exp_result;
148 s2[n] = 23;
149 s1[len] = 0;
150 s2[len] = 0;
151 if (exp_result < 0)
152 s2[len] = 32;
153 else if (exp_result > 0)
154 s1[len] = 64;
155 if (len >= n)
156 s2[n - 1] -= exp_result;
157
158 do_one_test (json_ctx, impl, s1, s2, n, exp_result);
159 }
160
161 json_array_end (json_ctx);
162 json_element_object_end (json_ctx);
163 }
164
165 static void
166 do_one_test_page_boundary (json_ctx_t *json_ctx, CHAR *s1, CHAR *s2,
167 size_t align1, size_t align2, size_t len,
168 size_t n, int exp_result)
169 {
170 json_element_object_begin (json_ctx);
171 json_attr_uint (json_ctx, "strlen", (double) len);
172 json_attr_uint (json_ctx, "len", (double) n);
173 json_attr_uint (json_ctx, "align1", (double) align1);
174 json_attr_uint (json_ctx, "align2", (double) align2);
175 json_array_begin (json_ctx, "timings");
176 FOR_EACH_IMPL (impl, 0)
177 do_one_test (json_ctx, impl, s1, s2, n, exp_result);
178 json_array_end (json_ctx);
179 json_element_object_end (json_ctx);
180 }
181
182 static void
183 do_test_page_boundary (json_ctx_t *json_ctx)
184 {
185 /* To trigger bug 25933, we need a size that is equal to the vector
186 length times 4. In the case of AVX2 for Intel, we need 32 * 4. We
187 make this test generic and run it for all architectures as additional
188 boundary testing for such related algorithms. */
189 size_t size = 32 * 4;
190 size_t len;
191 CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size);
192 CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size);
193 int exp_result;
194
195 memset (s1, 'a', page_size);
196 memset (s2, 'a', page_size);
197
198 s1[(page_size / CHARBYTES) - 1] = (CHAR) 0;
199
200 /* Iterate over a size that is just below where we expect the bug to
201 trigger up to the size we expect will trigger the bug e.g. [99-128].
202 Likewise iterate the start of two strings between 30 and 31 bytes
203 away from the boundary to simulate alignment changes. */
204 for (size_t s = 99; s <= size; s++)
205 for (size_t s1a = 30; s1a < 32; s1a++)
206 for (size_t s2a = 30; s2a < 32; s2a++)
207 {
208 size_t align1 = (page_size / CHARBYTES - s) - s1a;
209 size_t align2 = (page_size / CHARBYTES - s) - s2a;
210 CHAR *s1p = s1 + align1;
211 CHAR *s2p = s2 + align2;
212 len = (page_size / CHARBYTES) - 1 - align1;
213 exp_result = STRNCMP (s1p, s2p, s);
214 do_one_test_page_boundary (json_ctx, s1p, s2p, align1, align2,
215 len, s, exp_result);
216 }
217 }
218
219 static void
220 do_one_test_page (json_ctx_t *json_ctx, size_t offset1, size_t offset2,
221 CHAR *s2)
222 {
223 CHAR *s1;
224 int exp_result;
225
226 if (offset1 * CHARBYTES >= page_size
227 || offset2 * CHARBYTES >= page_size)
228 return;
229
230 s1 = (CHAR *) buf1;
231 s1 += offset1;
232 s2 += offset2;
233
234 size_t len = (page_size / CHARBYTES) - offset1;
235
236 exp_result= *s1;
237
238 json_element_object_begin (json_ctx);
239 json_attr_uint (json_ctx, "strlen", (double) len);
240 json_attr_uint (json_ctx, "len", (double) page_size);
241 json_attr_uint (json_ctx, "align1", (double) offset1);
242 json_attr_uint (json_ctx, "align2", (double) offset2);
243 json_array_begin (json_ctx, "timings");
244 {
245 FOR_EACH_IMPL (impl, 0)
246 do_one_test (json_ctx, impl, s1, s2, page_size, -exp_result);
247 }
248 json_array_end (json_ctx);
249 json_element_object_end (json_ctx);
250
251 json_element_object_begin (json_ctx);
252 json_attr_uint (json_ctx, "strlen", (double) len);
253 json_attr_uint (json_ctx, "len", (double) page_size);
254 json_attr_uint (json_ctx, "align1", (double) offset1);
255 json_attr_uint (json_ctx, "align2", (double) offset2);
256 json_array_begin (json_ctx, "timings");
257 {
258 FOR_EACH_IMPL (impl, 0)
259 do_one_test (json_ctx, impl, s1, s2, page_size, exp_result);
260 }
261 json_array_end (json_ctx);
262 json_element_object_end (json_ctx);
263 }
264
265 static void
266 do_test_page (json_ctx_t *json_ctx)
267 {
268 size_t i;
269 CHAR *s1, *s2;
270
271 s1 = (CHAR *) buf1;
272 /* Fill buf1 with 23. */
273 for (i = 0; i < (page_size / CHARBYTES) - 1; i++)
274 s1[i] = 23;
275 s1[i] = 0;
276
277 /* Make a copy of buf1. */
278 s2 = STRDUP (s1);
279
280 /* Test should terminate within the page boundary. */
281 for (i = 0; i < (108 / CHARBYTES); ++i)
282 do_one_test_page (json_ctx, ((page_size - 108) / CHARBYTES) + i,
283 ((page_size - 1460) / CHARBYTES), s2);
284
285 free (s2);
286 }
287
288 int
289 test_main (void)
290 {
291 json_ctx_t json_ctx;
292 size_t i, j, len;
293 size_t pg_sz = getpagesize ();
294
295 test_init ();
296
297 json_init (&json_ctx, 0, stdout);
298
299 json_document_begin (&json_ctx);
300 json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
301
302 json_attr_object_begin (&json_ctx, "functions");
303 json_attr_object_begin (&json_ctx, TEST_NAME);
304 json_attr_string (&json_ctx, "bench-variant", "default");
305
306 json_array_begin (&json_ctx, "ifuncs");
307 FOR_EACH_IMPL (impl, 0)
308 json_element_string (&json_ctx, impl->name);
309 json_array_end (&json_ctx);
310
311 json_array_begin (&json_ctx, "results");
312
313 for (i = 0; i < 16; ++i)
314 {
315 do_test (&json_ctx, 0, 0, 8, i, 127, 0);
316 do_test (&json_ctx, 0, 0, 8, i, 127, -1);
317 do_test (&json_ctx, 0, 0, 8, i, 127, 1);
318 do_test (&json_ctx, i, i, 8, i, 127, 0);
319 do_test (&json_ctx, i, i, 8, i, 127, 1);
320 do_test (&json_ctx, i, i, 8, i, 127, -1);
321 do_test (&json_ctx, i, 2 * i, 8, i, 127, 0);
322 do_test (&json_ctx, 2 * i, i, 8, i, 127, 1);
323 do_test (&json_ctx, i, 3 * i, 8, i, 127, -1);
324 do_test (&json_ctx, 0, 0, 8, i, 255, 0);
325 do_test (&json_ctx, 0, 0, 8, i, 255, -1);
326 do_test (&json_ctx, 0, 0, 8, i, 255, 1);
327 do_test (&json_ctx, i, i, 8, i, 255, 0);
328 do_test (&json_ctx, i, i, 8, i, 255, 1);
329 do_test (&json_ctx, i, i, 8, i, 255, -1);
330 do_test (&json_ctx, i, 2 * i, 8, i, 255, 0);
331 do_test (&json_ctx, 2 * i, i, 8, i, 255, 1);
332 do_test (&json_ctx, i, 3 * i, 8, i, 255, -1);
333 }
334
335 for (len = 0; len <= 128; len += 64)
336 {
337 for (i = 1; i <= 8192;)
338 {
339 /* No page crosses. */
340 do_test (&json_ctx, 0, 0, i, i + len, 127, 0);
341 do_test (&json_ctx, i * CHARBYTES, 0, i, i + len, 127, 0);
342 do_test (&json_ctx, 0, i * CHARBYTES, i, i + len, 127, 0);
343
344 /* False page crosses. */
345 do_test (&json_ctx, pg_sz / 2, pg_sz / 2 - CHARBYTES, i, i + len,
346 127, 0);
347 do_test (&json_ctx, pg_sz / 2 - CHARBYTES, pg_sz / 2, i, i + len,
348 127, 0);
349
350 do_test (&json_ctx, pg_sz - (i * CHARBYTES), 0, i, i + len, 127,
351 0);
352 do_test (&json_ctx, 0, pg_sz - (i * CHARBYTES), i, i + len, 127,
353 0);
354
355 /* Real page cross. */
356 for (j = 16; j < 128; j += 16)
357 {
358 do_test (&json_ctx, pg_sz - j, 0, i, i + len, 127, 0);
359 do_test (&json_ctx, 0, pg_sz - j, i, i + len, 127, 0);
360
361 do_test (&json_ctx, pg_sz - j, pg_sz - j / 2, i, i + len,
362 127, 0);
363 do_test (&json_ctx, pg_sz - j / 2, pg_sz - j, i, i + len,
364 127, 0);
365 }
366
367 if (i < 32)
368 {
369 ++i;
370 }
371 else if (i < 160)
372 {
373 i += 8;
374 }
375 else if (i < 256)
376 {
377 i += 32;
378 }
379 else
380 {
381 i *= 2;
382 }
383 }
384 }
385
386 for (i = 1; i < 8; ++i)
387 {
388 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 127, 0);
389 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 127, 1);
390 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 127, -1);
391 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 255, 0);
392 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 255, 1);
393 do_test (&json_ctx, 0, 0, 8 << i, 16 << i, 255, -1);
394 do_test (&json_ctx, 8 - i, 2 * i, 8 << i, 16 << i, 127, 0);
395 do_test (&json_ctx, 8 - i, 2 * i, 8 << i, 16 << i, 127, 1);
396 do_test (&json_ctx, 2 * i, i, 8 << i, 16 << i, 255, 0);
397 do_test (&json_ctx, 2 * i, i, 8 << i, 16 << i, 255, 1);
398 }
399
400 do_test_limit (&json_ctx, 4, 0, 21, 20, 127, 0);
401 do_test_limit (&json_ctx, 0, 4, 21, 20, 127, 0);
402 do_test_limit (&json_ctx, 8, 0, 25, 24, 127, 0);
403 do_test_limit (&json_ctx, 0, 8, 25, 24, 127, 0);
404
405 for (i = 0; i < 8; ++i)
406 {
407 do_test_limit (&json_ctx, 0, 0, 17 - i, 16 - i, 127, 0);
408 do_test_limit (&json_ctx, 0, 0, 17 - i, 16 - i, 255, 0);
409 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 127, 0);
410 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 127, 1);
411 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 127, -1);
412 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 255, 0);
413 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 255, 1);
414 do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 255, -1);
415 }
416
417 do_test_page_boundary (&json_ctx);
418 do_test_page (&json_ctx);
419
420 json_array_end (&json_ctx);
421 json_attr_object_end (&json_ctx);
422 json_attr_object_end (&json_ctx);
423 json_document_end (&json_ctx);
424
425 return ret;
426 }
427
428 #include <support/test-driver.c>
429
430 #ifndef WIDE
431 # undef STRNCMP
432 # define STRNCMP generic_strncmp
433 # define libc_hidden_builtin_def(X)
434 # include <string/strncmp.c>
435 #endif