xref: /netbsd-src/external/bsd/jemalloc/dist/test/unit/fb.c (revision 7bdf38e5b7a28439665f2fdeff81e36913eef7dd)
1 #include "test/jemalloc_test.h"
2 
3 #include "jemalloc/internal/fb.h"
4 #include "test/nbits.h"
5 
6 static void
7 do_test_init(size_t nbits) {
8 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
9 	fb_group_t *fb = malloc(sz);
10 	/* Junk fb's contents. */
11 	memset(fb, 99, sz);
12 	fb_init(fb, nbits);
13 	for (size_t i = 0; i < nbits; i++) {
14 		expect_false(fb_get(fb, nbits, i),
15 		    "bitmap should start empty");
16 	}
17 	free(fb);
18 }
19 
20 TEST_BEGIN(test_fb_init) {
21 #define NB(nbits) \
22 	do_test_init(nbits);
23 	NBITS_TAB
24 #undef NB
25 }
26 TEST_END
27 
28 static void
29 do_test_get_set_unset(size_t nbits) {
30 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
31 	fb_group_t *fb = malloc(sz);
32 	fb_init(fb, nbits);
33 	/* Set the bits divisible by 3. */
34 	for (size_t i = 0; i < nbits; i++) {
35 		if (i % 3 == 0) {
36 			fb_set(fb, nbits, i);
37 		}
38 	}
39 	/* Check them. */
40 	for (size_t i = 0; i < nbits; i++) {
41 		expect_b_eq(i % 3 == 0, fb_get(fb, nbits, i),
42 		    "Unexpected bit at position %zu", i);
43 	}
44 	/* Unset those divisible by 5. */
45 	for (size_t i = 0; i < nbits; i++) {
46 		if (i % 5 == 0) {
47 			fb_unset(fb, nbits, i);
48 		}
49 	}
50 	/* Check them. */
51 	for (size_t i = 0; i < nbits; i++) {
52 		expect_b_eq(i % 3 == 0 && i % 5 != 0, fb_get(fb, nbits, i),
53 		    "Unexpected bit at position %zu", i);
54 	}
55 	free(fb);
56 }
57 
58 TEST_BEGIN(test_get_set_unset) {
59 #define NB(nbits) \
60 	do_test_get_set_unset(nbits);
61 	NBITS_TAB
62 #undef NB
63 }
64 TEST_END
65 
66 static ssize_t
67 find_3_5_compute(ssize_t i, size_t nbits, bool bit, bool forward) {
68 	for(; i < (ssize_t)nbits && i >= 0; i += (forward ? 1 : -1)) {
69 		bool expected_bit = i % 3 == 0 || i % 5 == 0;
70 		if (expected_bit == bit) {
71 			return i;
72 		}
73 	}
74 	return forward ? (ssize_t)nbits : (ssize_t)-1;
75 }
76 
77 static void
78 do_test_search_simple(size_t nbits) {
79 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
80 	fb_group_t *fb = malloc(sz);
81 	fb_init(fb, nbits);
82 
83 	/* We pick multiples of 3 or 5. */
84 	for (size_t i = 0; i < nbits; i++) {
85 		if (i % 3 == 0) {
86 			fb_set(fb, nbits, i);
87 		}
88 		/* This tests double-setting a little, too. */
89 		if (i % 5 == 0) {
90 			fb_set(fb, nbits, i);
91 		}
92 	}
93 	for (size_t i = 0; i < nbits; i++) {
94 		size_t ffs_compute = find_3_5_compute(i, nbits, true, true);
95 		size_t ffs_search = fb_ffs(fb, nbits, i);
96 		expect_zu_eq(ffs_compute, ffs_search, "ffs mismatch at %zu", i);
97 
98 		ssize_t fls_compute = find_3_5_compute(i, nbits, true, false);
99 		size_t fls_search = fb_fls(fb, nbits, i);
100 		expect_zu_eq(fls_compute, fls_search, "fls mismatch at %zu", i);
101 
102 		size_t ffu_compute = find_3_5_compute(i, nbits, false, true);
103 		size_t ffu_search = fb_ffu(fb, nbits, i);
104 		expect_zu_eq(ffu_compute, ffu_search, "ffu mismatch at %zu", i);
105 
106 		size_t flu_compute = find_3_5_compute(i, nbits, false, false);
107 		size_t flu_search = fb_flu(fb, nbits, i);
108 		expect_zu_eq(flu_compute, flu_search, "flu mismatch at %zu", i);
109 	}
110 
111 	free(fb);
112 }
113 
114 TEST_BEGIN(test_search_simple) {
115 #define NB(nbits) \
116 	do_test_search_simple(nbits);
117 	NBITS_TAB
118 #undef NB
119 }
120 TEST_END
121 
122 static void
123 expect_exhaustive_results(fb_group_t *mostly_full, fb_group_t *mostly_empty,
124     size_t nbits, size_t special_bit, size_t position) {
125 	if (position < special_bit) {
126 		expect_zu_eq(special_bit, fb_ffs(mostly_empty, nbits, position),
127 		    "mismatch at %zu, %zu", position, special_bit);
128 		expect_zd_eq(-1, fb_fls(mostly_empty, nbits, position),
129 		    "mismatch at %zu, %zu", position, special_bit);
130 		expect_zu_eq(position, fb_ffu(mostly_empty, nbits, position),
131 		    "mismatch at %zu, %zu", position, special_bit);
132 		expect_zd_eq(position, fb_flu(mostly_empty, nbits, position),
133 		    "mismatch at %zu, %zu", position, special_bit);
134 
135 		expect_zu_eq(position, fb_ffs(mostly_full, nbits, position),
136 		    "mismatch at %zu, %zu", position, special_bit);
137 		expect_zd_eq(position, fb_fls(mostly_full, nbits, position),
138 		    "mismatch at %zu, %zu", position, special_bit);
139 		expect_zu_eq(special_bit, fb_ffu(mostly_full, nbits, position),
140 		    "mismatch at %zu, %zu", position, special_bit);
141 		expect_zd_eq(-1, fb_flu(mostly_full, nbits, position),
142 		    "mismatch at %zu, %zu", position, special_bit);
143 	} else if (position == special_bit) {
144 		expect_zu_eq(special_bit, fb_ffs(mostly_empty, nbits, position),
145 		    "mismatch at %zu, %zu", position, special_bit);
146 		expect_zd_eq(special_bit, fb_fls(mostly_empty, nbits, position),
147 		    "mismatch at %zu, %zu", position, special_bit);
148 		expect_zu_eq(position + 1, fb_ffu(mostly_empty, nbits, position),
149 		    "mismatch at %zu, %zu", position, special_bit);
150 		expect_zd_eq(position - 1, fb_flu(mostly_empty, nbits,
151 		    position), "mismatch at %zu, %zu", position, special_bit);
152 
153 		expect_zu_eq(position + 1, fb_ffs(mostly_full, nbits, position),
154 		    "mismatch at %zu, %zu", position, special_bit);
155 		expect_zd_eq(position - 1, fb_fls(mostly_full, nbits,
156 		    position), "mismatch at %zu, %zu", position, special_bit);
157 		expect_zu_eq(position, fb_ffu(mostly_full, nbits, position),
158 		    "mismatch at %zu, %zu", position, special_bit);
159 		expect_zd_eq(position, fb_flu(mostly_full, nbits, position),
160 		    "mismatch at %zu, %zu", position, special_bit);
161 	} else {
162 		/* position > special_bit. */
163 		expect_zu_eq(nbits, fb_ffs(mostly_empty, nbits, position),
164 		    "mismatch at %zu, %zu", position, special_bit);
165 		expect_zd_eq(special_bit, fb_fls(mostly_empty, nbits,
166 		    position), "mismatch at %zu, %zu", position, special_bit);
167 		expect_zu_eq(position, fb_ffu(mostly_empty, nbits, position),
168 		    "mismatch at %zu, %zu", position, special_bit);
169 		expect_zd_eq(position, fb_flu(mostly_empty, nbits, position),
170 		    "mismatch at %zu, %zu", position, special_bit);
171 
172 		expect_zu_eq(position, fb_ffs(mostly_full, nbits, position),
173 		    "mismatch at %zu, %zu", position, special_bit);
174 		expect_zd_eq(position, fb_fls(mostly_full, nbits, position),
175 		    "mismatch at %zu, %zu", position, special_bit);
176 		expect_zu_eq(nbits, fb_ffu(mostly_full, nbits, position),
177 		    "mismatch at %zu, %zu", position, special_bit);
178 		expect_zd_eq(special_bit, fb_flu(mostly_full, nbits, position),
179 		    "mismatch at %zu, %zu", position, special_bit);
180 	}
181 }
182 
183 static void
184 do_test_search_exhaustive(size_t nbits) {
185 	/* This test is quadratic; let's not get too big. */
186 	if (nbits > 1000) {
187 		return;
188 	}
189 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
190 	fb_group_t *empty = malloc(sz);
191 	fb_init(empty, nbits);
192 	fb_group_t *full = malloc(sz);
193 	fb_init(full, nbits);
194 	fb_set_range(full, nbits, 0, nbits);
195 
196 	for (size_t i = 0; i < nbits; i++) {
197 		fb_set(empty, nbits, i);
198 		fb_unset(full, nbits, i);
199 
200 		for (size_t j = 0; j < nbits; j++) {
201 			expect_exhaustive_results(full, empty, nbits, i, j);
202 		}
203 		fb_unset(empty, nbits, i);
204 		fb_set(full, nbits, i);
205 	}
206 
207 	free(empty);
208 	free(full);
209 }
210 
211 TEST_BEGIN(test_search_exhaustive) {
212 #define NB(nbits) \
213 	do_test_search_exhaustive(nbits);
214 	NBITS_TAB
215 #undef NB
216 }
217 TEST_END
218 
219 TEST_BEGIN(test_range_simple) {
220 	/*
221 	 * Just pick a constant big enough to have nontrivial middle sizes, and
222 	 * big enough that usages of things like weirdnum (below) near the
223 	 * beginning fit comfortably into the beginning of the bitmap.
224 	 */
225 	size_t nbits = 64 * 10;
226 	size_t ngroups = FB_NGROUPS(nbits);
227 	fb_group_t *fb = malloc(sizeof(fb_group_t) * ngroups);
228 	fb_init(fb, nbits);
229 	for (size_t i = 0; i < nbits; i++) {
230 		if (i % 2 == 0) {
231 			fb_set_range(fb, nbits, i, 1);
232 		}
233 	}
234 	for (size_t i = 0; i < nbits; i++) {
235 		expect_b_eq(i % 2 == 0, fb_get(fb, nbits, i),
236 		    "mismatch at position %zu", i);
237 	}
238 	fb_set_range(fb, nbits, 0, nbits / 2);
239 	fb_unset_range(fb, nbits, nbits / 2, nbits / 2);
240 	for (size_t i = 0; i < nbits; i++) {
241 		expect_b_eq(i < nbits / 2, fb_get(fb, nbits, i),
242 		    "mismatch at position %zu", i);
243 	}
244 
245 	static const size_t weirdnum = 7;
246 	fb_set_range(fb, nbits, 0, nbits);
247 	fb_unset_range(fb, nbits, weirdnum, FB_GROUP_BITS + weirdnum);
248 	for (size_t i = 0; i < nbits; i++) {
249 		expect_b_eq(7 <= i && i <= 2 * weirdnum + FB_GROUP_BITS - 1,
250 		    !fb_get(fb, nbits, i), "mismatch at position %zu", i);
251 	}
252 	free(fb);
253 }
254 TEST_END
255 
256 static void
257 do_test_empty_full_exhaustive(size_t nbits) {
258 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
259 	fb_group_t *empty = malloc(sz);
260 	fb_init(empty, nbits);
261 	fb_group_t *full = malloc(sz);
262 	fb_init(full, nbits);
263 	fb_set_range(full, nbits, 0, nbits);
264 
265 	expect_true(fb_full(full, nbits), "");
266 	expect_false(fb_empty(full, nbits), "");
267 	expect_false(fb_full(empty, nbits), "");
268 	expect_true(fb_empty(empty, nbits), "");
269 
270 	for (size_t i = 0; i < nbits; i++) {
271 		fb_set(empty, nbits, i);
272 		fb_unset(full, nbits, i);
273 
274 		expect_false(fb_empty(empty, nbits), "error at bit %zu", i);
275 		if (nbits != 1) {
276 			expect_false(fb_full(empty, nbits),
277 			    "error at bit %zu", i);
278 			expect_false(fb_empty(full, nbits),
279 			    "error at bit %zu", i);
280 		} else {
281 			expect_true(fb_full(empty, nbits),
282 			    "error at bit %zu", i);
283 			expect_true(fb_empty(full, nbits),
284 			    "error at bit %zu", i);
285 		}
286 		expect_false(fb_full(full, nbits), "error at bit %zu", i);
287 
288 		fb_unset(empty, nbits, i);
289 		fb_set(full, nbits, i);
290 	}
291 
292 	free(empty);
293 	free(full);
294 }
295 
296 TEST_BEGIN(test_empty_full) {
297 #define NB(nbits) \
298 	do_test_empty_full_exhaustive(nbits);
299 	NBITS_TAB
300 #undef NB
301 }
302 TEST_END
303 
304 /*
305  * This tests both iter_range and the longest range functionality, which is
306  * built closely on top of it.
307  */
308 TEST_BEGIN(test_iter_range_simple) {
309 	size_t set_limit = 30;
310 	size_t nbits = 100;
311 	fb_group_t fb[FB_NGROUPS(100)];
312 
313 	fb_init(fb, nbits);
314 
315 	/*
316 	 * Failing to initialize these can lead to build failures with -Wall;
317 	 * the compiler can't prove that they're set.
318 	 */
319 	size_t begin = (size_t)-1;
320 	size_t len = (size_t)-1;
321 	bool result;
322 
323 	/* A set of checks with only the first set_limit bits *set*. */
324 	fb_set_range(fb, nbits, 0, set_limit);
325 	expect_zu_eq(set_limit, fb_srange_longest(fb, nbits),
326 	    "Incorrect longest set range");
327 	expect_zu_eq(nbits - set_limit, fb_urange_longest(fb, nbits),
328 	    "Incorrect longest unset range");
329 	for (size_t i = 0; i < set_limit; i++) {
330 		result = fb_srange_iter(fb, nbits, i, &begin, &len);
331 		expect_true(result, "Should have found a range at %zu", i);
332 		expect_zu_eq(i, begin, "Incorrect begin at %zu", i);
333 		expect_zu_eq(set_limit - i, len, "Incorrect len at %zu", i);
334 
335 		result = fb_urange_iter(fb, nbits, i, &begin, &len);
336 		expect_true(result, "Should have found a range at %zu", i);
337 		expect_zu_eq(set_limit, begin, "Incorrect begin at %zu", i);
338 		expect_zu_eq(nbits - set_limit, len, "Incorrect len at %zu", i);
339 
340 		result = fb_srange_riter(fb, nbits, i, &begin, &len);
341 		expect_true(result, "Should have found a range at %zu", i);
342 		expect_zu_eq(0, begin, "Incorrect begin at %zu", i);
343 		expect_zu_eq(i + 1, len, "Incorrect len at %zu", i);
344 
345 		result = fb_urange_riter(fb, nbits, i, &begin, &len);
346 		expect_false(result, "Should not have found a range at %zu", i);
347 	}
348 	for (size_t i = set_limit; i < nbits; i++) {
349 		result = fb_srange_iter(fb, nbits, i, &begin, &len);
350 		expect_false(result, "Should not have found a range at %zu", i);
351 
352 		result = fb_urange_iter(fb, nbits, i, &begin, &len);
353 		expect_true(result, "Should have found a range at %zu", i);
354 		expect_zu_eq(i, begin, "Incorrect begin at %zu", i);
355 		expect_zu_eq(nbits - i, len, "Incorrect len at %zu", i);
356 
357 		result = fb_srange_riter(fb, nbits, i, &begin, &len);
358 		expect_true(result, "Should have found a range at %zu", i);
359 		expect_zu_eq(0, begin, "Incorrect begin at %zu", i);
360 		expect_zu_eq(set_limit, len, "Incorrect len at %zu", i);
361 
362 		result = fb_urange_riter(fb, nbits, i, &begin, &len);
363 		expect_true(result, "Should have found a range at %zu", i);
364 		expect_zu_eq(set_limit, begin, "Incorrect begin at %zu", i);
365 		expect_zu_eq(i - set_limit + 1, len, "Incorrect len at %zu", i);
366 	}
367 
368 	/* A set of checks with only the first set_limit bits *unset*. */
369 	fb_unset_range(fb, nbits, 0, set_limit);
370 	fb_set_range(fb, nbits, set_limit, nbits - set_limit);
371 	expect_zu_eq(nbits - set_limit, fb_srange_longest(fb, nbits),
372 	    "Incorrect longest set range");
373 	expect_zu_eq(set_limit, fb_urange_longest(fb, nbits),
374 	    "Incorrect longest unset range");
375 	for (size_t i = 0; i < set_limit; i++) {
376 		result = fb_srange_iter(fb, nbits, i, &begin, &len);
377 		expect_true(result, "Should have found a range at %zu", i);
378 		expect_zu_eq(set_limit, begin, "Incorrect begin at %zu", i);
379 		expect_zu_eq(nbits - set_limit, len, "Incorrect len at %zu", i);
380 
381 		result = fb_urange_iter(fb, nbits, i, &begin, &len);
382 		expect_true(result, "Should have found a range at %zu", i);
383 		expect_zu_eq(i, begin, "Incorrect begin at %zu", i);
384 		expect_zu_eq(set_limit - i, len, "Incorrect len at %zu", i);
385 
386 		result = fb_srange_riter(fb, nbits, i, &begin, &len);
387 		expect_false(result, "Should not have found a range at %zu", i);
388 
389 		result = fb_urange_riter(fb, nbits, i, &begin, &len);
390 		expect_true(result, "Should not have found a range at %zu", i);
391 		expect_zu_eq(0, begin, "Incorrect begin at %zu", i);
392 		expect_zu_eq(i + 1, len, "Incorrect len at %zu", i);
393 	}
394 	for (size_t i = set_limit; i < nbits; i++) {
395 		result = fb_srange_iter(fb, nbits, i, &begin, &len);
396 		expect_true(result, "Should have found a range at %zu", i);
397 		expect_zu_eq(i, begin, "Incorrect begin at %zu", i);
398 		expect_zu_eq(nbits - i, len, "Incorrect len at %zu", i);
399 
400 		result = fb_urange_iter(fb, nbits, i, &begin, &len);
401 		expect_false(result, "Should not have found a range at %zu", i);
402 
403 		result = fb_srange_riter(fb, nbits, i, &begin, &len);
404 		expect_true(result, "Should have found a range at %zu", i);
405 		expect_zu_eq(set_limit, begin, "Incorrect begin at %zu", i);
406 		expect_zu_eq(i - set_limit + 1, len, "Incorrect len at %zu", i);
407 
408 		result = fb_urange_riter(fb, nbits, i, &begin, &len);
409 		expect_true(result, "Should have found a range at %zu", i);
410 		expect_zu_eq(0, begin, "Incorrect begin at %zu", i);
411 		expect_zu_eq(set_limit, len, "Incorrect len at %zu", i);
412 	}
413 
414 }
415 TEST_END
416 
417 /*
418  * Doing this bit-by-bit is too slow for a real implementation, but for testing
419  * code, it's easy to get right.  In the exhaustive tests, we'll compare the
420  * (fast but tricky) real implementation against the (slow but simple) testing
421  * one.
422  */
423 static bool
424 fb_iter_simple(fb_group_t *fb, size_t nbits, size_t start, size_t *r_begin,
425     size_t *r_len, bool val, bool forward) {
426 	ssize_t stride = (forward ? (ssize_t)1 : (ssize_t)-1);
427 	ssize_t range_begin = (ssize_t)start;
428 	for (; range_begin != (ssize_t)nbits && range_begin != -1;
429 	    range_begin += stride) {
430 		if (fb_get(fb, nbits, range_begin) == val) {
431 			ssize_t range_end = range_begin;
432 			for (; range_end != (ssize_t)nbits && range_end != -1;
433 			    range_end += stride) {
434 				if (fb_get(fb, nbits, range_end) != val) {
435 					break;
436 				}
437 			}
438 			if (forward) {
439 				*r_begin = range_begin;
440 				*r_len = range_end - range_begin;
441 			} else {
442 				*r_begin = range_end + 1;
443 				*r_len = range_begin - range_end;
444 			}
445 			return true;
446 		}
447 	}
448 	return false;
449 }
450 
451 /* Similar, but for finding longest ranges. */
452 static size_t
453 fb_range_longest_simple(fb_group_t *fb, size_t nbits, bool val) {
454 	size_t longest_so_far = 0;
455 	for (size_t begin = 0; begin < nbits; begin++) {
456 		if (fb_get(fb, nbits, begin) != val) {
457 			continue;
458 		}
459 		size_t end = begin + 1;
460 		for (; end < nbits; end++) {
461 			if (fb_get(fb, nbits, end) != val) {
462 				break;
463 			}
464 		}
465 		if (end - begin > longest_so_far) {
466 			longest_so_far = end - begin;
467 		}
468 	}
469 	return longest_so_far;
470 }
471 
472 static void
473 expect_iter_results_at(fb_group_t *fb, size_t nbits, size_t pos,
474     bool val, bool forward) {
475 	bool iter_res;
476 	size_t iter_begin JEMALLOC_CC_SILENCE_INIT(0);
477 	size_t iter_len JEMALLOC_CC_SILENCE_INIT(0);
478 	if (val) {
479 		if (forward) {
480 			iter_res = fb_srange_iter(fb, nbits, pos,
481 			    &iter_begin, &iter_len);
482 		} else {
483 			iter_res = fb_srange_riter(fb, nbits, pos,
484 			    &iter_begin, &iter_len);
485 		}
486 	} else {
487 		if (forward) {
488 			iter_res = fb_urange_iter(fb, nbits, pos,
489 			    &iter_begin, &iter_len);
490 		} else {
491 			iter_res = fb_urange_riter(fb, nbits, pos,
492 			    &iter_begin, &iter_len);
493 		}
494 	}
495 
496 	bool simple_iter_res;
497 	/*
498 	 * These are dead stores, but the compiler can't always figure that out
499 	 * statically, and warns on the uninitialized variable.
500 	 */
501 	size_t simple_iter_begin = 0;
502 	size_t simple_iter_len = 0;
503 	simple_iter_res = fb_iter_simple(fb, nbits, pos, &simple_iter_begin,
504 	    &simple_iter_len, val, forward);
505 
506 	expect_b_eq(iter_res, simple_iter_res, "Result mismatch at %zu", pos);
507 	if (iter_res && simple_iter_res) {
508 		assert_zu_eq(iter_begin, simple_iter_begin,
509 		    "Begin mismatch at %zu", pos);
510 		expect_zu_eq(iter_len, simple_iter_len,
511 		    "Length mismatch at %zu", pos);
512 	}
513 }
514 
515 static void
516 expect_iter_results(fb_group_t *fb, size_t nbits) {
517 	for (size_t i = 0; i < nbits; i++) {
518 		expect_iter_results_at(fb, nbits, i, false, false);
519 		expect_iter_results_at(fb, nbits, i, false, true);
520 		expect_iter_results_at(fb, nbits, i, true, false);
521 		expect_iter_results_at(fb, nbits, i, true, true);
522 	}
523 	expect_zu_eq(fb_range_longest_simple(fb, nbits, true),
524 	    fb_srange_longest(fb, nbits), "Longest range mismatch");
525 	expect_zu_eq(fb_range_longest_simple(fb, nbits, false),
526 	    fb_urange_longest(fb, nbits), "Longest range mismatch");
527 }
528 
529 static void
530 set_pattern_3(fb_group_t *fb, size_t nbits, bool zero_val) {
531 	for (size_t i = 0; i < nbits; i++) {
532 		if ((i % 6 < 3 && zero_val) || (i % 6 >= 3 && !zero_val)) {
533 			fb_set(fb, nbits, i);
534 		} else {
535 			fb_unset(fb, nbits, i);
536 		}
537 	}
538 }
539 
540 static void
541 do_test_iter_range_exhaustive(size_t nbits) {
542 	/* This test is also pretty slow. */
543 	if (nbits > 1000) {
544 		return;
545 	}
546 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
547 	fb_group_t *fb = malloc(sz);
548 	fb_init(fb, nbits);
549 
550 	set_pattern_3(fb, nbits, /* zero_val */ true);
551 	expect_iter_results(fb, nbits);
552 
553 	set_pattern_3(fb, nbits, /* zero_val */ false);
554 	expect_iter_results(fb, nbits);
555 
556 	fb_set_range(fb, nbits, 0, nbits);
557 	fb_unset_range(fb, nbits, 0, nbits / 2 == 0 ? 1 : nbits / 2);
558 	expect_iter_results(fb, nbits);
559 
560 	fb_unset_range(fb, nbits, 0, nbits);
561 	fb_set_range(fb, nbits, 0, nbits / 2 == 0 ? 1: nbits / 2);
562 	expect_iter_results(fb, nbits);
563 
564 	free(fb);
565 }
566 
567 /*
568  * Like test_iter_range_simple, this tests both iteration and longest-range
569  * computation.
570  */
571 TEST_BEGIN(test_iter_range_exhaustive) {
572 #define NB(nbits) \
573 	do_test_iter_range_exhaustive(nbits);
574 	NBITS_TAB
575 #undef NB
576 }
577 TEST_END
578 
579 /*
580  * If all set bits in the bitmap are contiguous, in [set_start, set_end),
581  * returns the number of set bits in [scount_start, scount_end).
582  */
583 static size_t
584 scount_contiguous(size_t set_start, size_t set_end, size_t scount_start,
585     size_t scount_end) {
586 	/* No overlap. */
587 	if (set_end <= scount_start || scount_end <= set_start) {
588 		return 0;
589 	}
590 	/* set range contains scount range */
591 	if (set_start <= scount_start && set_end >= scount_end) {
592 		return scount_end - scount_start;
593 	}
594 	/* scount range contains set range. */
595 	if (scount_start <= set_start && scount_end >= set_end) {
596 		return set_end - set_start;
597 	}
598 	/* Partial overlap, with set range starting first. */
599 	if (set_start < scount_start && set_end < scount_end) {
600 		return set_end - scount_start;
601 	}
602 	/* Partial overlap, with scount range starting first. */
603 	if (scount_start < set_start && scount_end < set_end) {
604 		return scount_end - set_start;
605 	}
606 	/*
607 	 * Trigger an assert failure; the above list should have been
608 	 * exhaustive.
609 	 */
610 	unreachable();
611 }
612 
613 static size_t
614 ucount_contiguous(size_t set_start, size_t set_end, size_t ucount_start,
615     size_t ucount_end) {
616 	/* No overlap. */
617 	if (set_end <= ucount_start || ucount_end <= set_start) {
618 		return ucount_end - ucount_start;
619 	}
620 	/* set range contains ucount range */
621 	if (set_start <= ucount_start && set_end >= ucount_end) {
622 		return 0;
623 	}
624 	/* ucount range contains set range. */
625 	if (ucount_start <= set_start && ucount_end >= set_end) {
626 		return (ucount_end - ucount_start) - (set_end - set_start);
627 	}
628 	/* Partial overlap, with set range starting first. */
629 	if (set_start < ucount_start && set_end < ucount_end) {
630 		return ucount_end - set_end;
631 	}
632 	/* Partial overlap, with ucount range starting first. */
633 	if (ucount_start < set_start && ucount_end < set_end) {
634 		return set_start - ucount_start;
635 	}
636 	/*
637 	 * Trigger an assert failure; the above list should have been
638 	 * exhaustive.
639 	 */
640 	unreachable();
641 }
642 
643 static void
644 expect_count_match_contiguous(fb_group_t *fb, size_t nbits, size_t set_start,
645     size_t set_end) {
646 	for (size_t i = 0; i < nbits; i++) {
647 		for (size_t j = i + 1; j <= nbits; j++) {
648 			size_t cnt = j - i;
649 			size_t scount_expected = scount_contiguous(set_start,
650 			    set_end, i, j);
651 			size_t scount_computed = fb_scount(fb, nbits, i, cnt);
652 			expect_zu_eq(scount_expected, scount_computed,
653 			    "fb_scount error with nbits=%zu, start=%zu, "
654 			    "cnt=%zu, with bits set in [%zu, %zu)",
655 			    nbits, i, cnt, set_start, set_end);
656 
657 			size_t ucount_expected = ucount_contiguous(set_start,
658 			    set_end, i, j);
659 			size_t ucount_computed = fb_ucount(fb, nbits, i, cnt);
660 			assert_zu_eq(ucount_expected, ucount_computed,
661 			    "fb_ucount error with nbits=%zu, start=%zu, "
662 			    "cnt=%zu, with bits set in [%zu, %zu)",
663 			    nbits, i, cnt, set_start, set_end);
664 
665 		}
666 	}
667 }
668 
669 static void
670 do_test_count_contiguous(size_t nbits) {
671 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
672 	fb_group_t *fb = malloc(sz);
673 
674 	fb_init(fb, nbits);
675 
676 	expect_count_match_contiguous(fb, nbits, 0, 0);
677 	for (size_t i = 0; i < nbits; i++) {
678 		fb_set(fb, nbits, i);
679 		expect_count_match_contiguous(fb, nbits, 0, i + 1);
680 	}
681 
682 	for (size_t i = 0; i < nbits; i++) {
683 		fb_unset(fb, nbits, i);
684 		expect_count_match_contiguous(fb, nbits, i + 1, nbits);
685 	}
686 
687 	free(fb);
688 }
689 
690 TEST_BEGIN(test_count_contiguous_simple) {
691 	enum {nbits = 300};
692 	fb_group_t fb[FB_NGROUPS(nbits)];
693 	fb_init(fb, nbits);
694 	/* Just an arbitrary number. */
695 	size_t start = 23;
696 
697 	fb_set_range(fb, nbits, start, 30 - start);
698 	expect_count_match_contiguous(fb, nbits, start, 30);
699 
700 	fb_set_range(fb, nbits, start, 40 - start);
701 	expect_count_match_contiguous(fb, nbits, start, 40);
702 
703 	fb_set_range(fb, nbits, start, 70 - start);
704 	expect_count_match_contiguous(fb, nbits, start, 70);
705 
706 	fb_set_range(fb, nbits, start, 120 - start);
707 	expect_count_match_contiguous(fb, nbits, start, 120);
708 
709 	fb_set_range(fb, nbits, start, 150 - start);
710 	expect_count_match_contiguous(fb, nbits, start, 150);
711 
712 	fb_set_range(fb, nbits, start, 200 - start);
713 	expect_count_match_contiguous(fb, nbits, start, 200);
714 
715 	fb_set_range(fb, nbits, start, 290 - start);
716 	expect_count_match_contiguous(fb, nbits, start, 290);
717 }
718 TEST_END
719 
720 TEST_BEGIN(test_count_contiguous) {
721 #define NB(nbits) \
722 	/* This test is *particularly* slow in debug builds. */ \
723 	if ((!config_debug && nbits < 300) || nbits < 150) { \
724 		do_test_count_contiguous(nbits); \
725 	}
726 	NBITS_TAB
727 #undef NB
728 }
729 TEST_END
730 
731 static void
732 expect_count_match_alternating(fb_group_t *fb_even, fb_group_t *fb_odd,
733     size_t nbits) {
734 	for (size_t i = 0; i < nbits; i++) {
735 		for (size_t j = i + 1; j <= nbits; j++) {
736 			size_t cnt = j - i;
737 			size_t odd_scount = cnt / 2
738 			    + (size_t)(cnt % 2 == 1 && i % 2 == 1);
739 			size_t odd_scount_computed = fb_scount(fb_odd, nbits,
740 			    i, j - i);
741 			assert_zu_eq(odd_scount, odd_scount_computed,
742 			    "fb_scount error with nbits=%zu, start=%zu, "
743 			    "cnt=%zu, with alternating bits set.",
744 			    nbits, i, j - i);
745 
746 			size_t odd_ucount = cnt / 2
747 			    + (size_t)(cnt % 2 == 1 && i % 2 == 0);
748 			size_t odd_ucount_computed = fb_ucount(fb_odd, nbits,
749 			    i, j - i);
750 			assert_zu_eq(odd_ucount, odd_ucount_computed,
751 			    "fb_ucount error with nbits=%zu, start=%zu, "
752 			    "cnt=%zu, with alternating bits set.",
753 			    nbits, i, j - i);
754 
755 			size_t even_scount = cnt / 2
756 			    + (size_t)(cnt % 2 == 1 && i % 2 == 0);
757 			size_t even_scount_computed = fb_scount(fb_even, nbits,
758 			    i, j - i);
759 			assert_zu_eq(even_scount, even_scount_computed,
760 			    "fb_scount error with nbits=%zu, start=%zu, "
761 			    "cnt=%zu, with alternating bits set.",
762 			    nbits, i, j - i);
763 
764 			size_t even_ucount = cnt / 2
765 			    + (size_t)(cnt % 2 == 1 && i % 2 == 1);
766 			size_t even_ucount_computed = fb_ucount(fb_even, nbits,
767 			    i, j - i);
768 			assert_zu_eq(even_ucount, even_ucount_computed,
769 			    "fb_ucount error with nbits=%zu, start=%zu, "
770 			    "cnt=%zu, with alternating bits set.",
771 			    nbits, i, j - i);
772 		}
773 	}
774 }
775 
776 static void
777 do_test_count_alternating(size_t nbits) {
778 	if (nbits > 1000) {
779 		return;
780 	}
781 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
782 	fb_group_t *fb_even = malloc(sz);
783 	fb_group_t *fb_odd = malloc(sz);
784 
785 	fb_init(fb_even, nbits);
786 	fb_init(fb_odd, nbits);
787 
788 	for (size_t i = 0; i < nbits; i++) {
789 		if (i % 2 == 0) {
790 			fb_set(fb_even, nbits, i);
791 		} else {
792 			fb_set(fb_odd, nbits, i);
793 		}
794 	}
795 
796 	expect_count_match_alternating(fb_even, fb_odd, nbits);
797 
798 	free(fb_even);
799 	free(fb_odd);
800 }
801 
802 TEST_BEGIN(test_count_alternating) {
803 #define NB(nbits) \
804 	do_test_count_alternating(nbits);
805 	NBITS_TAB
806 #undef NB
807 }
808 TEST_END
809 
810 static void
811 do_test_bit_op(size_t nbits, bool (*op)(bool a, bool b),
812     void (*fb_op)(fb_group_t *dst, fb_group_t *src1, fb_group_t *src2, size_t nbits)) {
813 	size_t sz = FB_NGROUPS(nbits) * sizeof(fb_group_t);
814 	fb_group_t *fb1 = malloc(sz);
815 	fb_group_t *fb2 = malloc(sz);
816 	fb_group_t *fb_result = malloc(sz);
817 	fb_init(fb1, nbits);
818 	fb_init(fb2, nbits);
819 	fb_init(fb_result, nbits);
820 
821 	/* Just two random numbers. */
822 	const uint64_t prng_init1 = (uint64_t)0X4E9A9DE6A35691CDULL;
823 	const uint64_t prng_init2 = (uint64_t)0X7856E396B063C36EULL;
824 
825 	uint64_t prng1 = prng_init1;
826 	uint64_t prng2 = prng_init2;
827 
828 	for (size_t i = 0; i < nbits; i++) {
829 		bool bit1 = ((prng1 & (1ULL << (i % 64))) != 0);
830 		bool bit2 = ((prng2 & (1ULL << (i % 64))) != 0);
831 
832 		if (bit1) {
833 			fb_set(fb1, nbits, i);
834 		}
835 		if (bit2) {
836 			fb_set(fb2, nbits, i);
837 		}
838 
839 		if (i % 64 == 0) {
840 			prng1 = prng_state_next_u64(prng1);
841 			prng2 = prng_state_next_u64(prng2);
842 		}
843 	}
844 
845 	fb_op(fb_result, fb1, fb2, nbits);
846 
847 	/* Reset the prngs to replay them. */
848 	prng1 = prng_init1;
849 	prng2 = prng_init2;
850 
851 	for (size_t i = 0; i < nbits; i++) {
852 		bool bit1 = ((prng1 & (1ULL << (i % 64))) != 0);
853 		bool bit2 = ((prng2 & (1ULL << (i % 64))) != 0);
854 
855 		/* Original bitmaps shouldn't change. */
856 		expect_b_eq(bit1, fb_get(fb1, nbits, i), "difference at bit %zu", i);
857 		expect_b_eq(bit2, fb_get(fb2, nbits, i), "difference at bit %zu", i);
858 
859 		/* New one should be bitwise and. */
860 		expect_b_eq(op(bit1, bit2), fb_get(fb_result, nbits, i),
861 		    "difference at bit %zu", i);
862 
863 		/* Update the same way we did last time. */
864 		if (i % 64 == 0) {
865 			prng1 = prng_state_next_u64(prng1);
866 			prng2 = prng_state_next_u64(prng2);
867 		}
868 	}
869 
870 	free(fb1);
871 	free(fb2);
872 	free(fb_result);
873 }
874 
875 static bool
876 binary_and(bool a, bool b) {
877 	return a & b;
878 }
879 
880 static void
881 do_test_bit_and(size_t nbits) {
882 	do_test_bit_op(nbits, &binary_and, &fb_bit_and);
883 }
884 
885 TEST_BEGIN(test_bit_and) {
886 #define NB(nbits) \
887 	do_test_bit_and(nbits);
888 	NBITS_TAB
889 #undef NB
890 }
891 TEST_END
892 
893 static bool
894 binary_or(bool a, bool b) {
895 	return a | b;
896 }
897 
898 static void
899 do_test_bit_or(size_t nbits) {
900 	do_test_bit_op(nbits, &binary_or, &fb_bit_or);
901 }
902 
903 TEST_BEGIN(test_bit_or) {
904 #define NB(nbits) \
905 	do_test_bit_or(nbits);
906 	NBITS_TAB
907 #undef NB
908 }
909 TEST_END
910 
911 static bool
912 binary_not(bool a, bool b) {
913 	(void)b;
914 	return !a;
915 }
916 
917 static void
918 fb_bit_not_shim(fb_group_t *dst, fb_group_t *src1, fb_group_t *src2,
919     size_t nbits) {
920 	(void)src2;
921 	fb_bit_not(dst, src1, nbits);
922 }
923 
924 static void
925 do_test_bit_not(size_t nbits) {
926 	do_test_bit_op(nbits, &binary_not, &fb_bit_not_shim);
927 }
928 
929 TEST_BEGIN(test_bit_not) {
930 #define NB(nbits) \
931 	do_test_bit_not(nbits);
932 	NBITS_TAB
933 #undef NB
934 }
935 TEST_END
936 
937 int
938 main(void) {
939 	return test_no_reentrancy(
940 	    test_fb_init,
941 	    test_get_set_unset,
942 	    test_search_simple,
943 	    test_search_exhaustive,
944 	    test_range_simple,
945 	    test_empty_full,
946 	    test_iter_range_simple,
947 	    test_iter_range_exhaustive,
948 	    test_count_contiguous_simple,
949 	    test_count_contiguous,
950 	    test_count_alternating,
951 	    test_bit_and,
952 	    test_bit_or,
953 	    test_bit_not);
954 }
955