common/lib/libc/gen/rpst.c

   1 /*      $NetBSD: rpst.c,v 1.9 2009/05/26 22:39:15 yamt Exp $    */
   2
   3 /*-
   4  * Copyright (c)2009 YAMAMOTO Takashi,
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 /*
  30  * radix priority search tree
  31  *
  32  * described in:
  33  *      SIAM J. COMPUT.
  34  *      Vol. 14, No. 2, May 1985
  35  *      PRIORITY SEARCH TREES
  36  *      EDWARD M. McCREIGHT
  37  *
  38  * ideas from linux:
  39  *      - grow tree height on-demand.
  40  *      - allow duplicated X values.  in that case, we act as a heap.
  41  */
  42
  43 #include <sys/cdefs.h>
  44
  45 #if defined(_KERNEL)
  46 __KERNEL_RCSID(0, "$NetBSD: rpst.c,v 1.9 2009/05/26 22:39:15 yamt Exp $");
  47 #include <sys/param.h>
  48 #else /* defined(_KERNEL) */
  49 __RCSID("$NetBSD: rpst.c,v 1.9 2009/05/26 22:39:15 yamt Exp $");
  50 #include <assert.h>
  51 #include <stdbool.h>
  52 #include <string.h>
  53 #if 1
  54 #define KASSERT assert
  55 #else
  56 #define KASSERT(a)
  57 #endif
  58 #endif /* defined(_KERNEL) */
  59
  60 #include <sys/rpst.h>
  61
  62 /*
  63  * rpst_init_tree: initialize a tree.
  64  */
  65
  66 void
  67 rpst_init_tree(struct rpst_tree *t)
  68 {
  69
  70         t->t_root = NULL;
  71         t->t_height = 0;
  72 }
  73
  74 /*
  75  * rpst_height2max: calculate the maximum index which can be handled by
  76  * a tree with the given height.
  77  *
  78  * 0  ... 0x0000000000000001
  79  * 1  ... 0x0000000000000003
  80  * 2  ... 0x0000000000000007
  81  * 3  ... 0x000000000000000f
  82  *
  83  * 31 ... 0x00000000ffffffff
  84  *
  85  * 63 ... 0xffffffffffffffff
  86  */
  87
  88 static uint64_t
  89 rpst_height2max(unsigned int height)
  90 {
  91
  92         KASSERT(height < 64);
  93         if (height == 63) {
  94                 return UINT64_MAX;
  95         }
  96         return (UINT64_C(1) << (height + 1)) - 1;
  97 }
  98
  99 /*
 100  * rpst_level2mask: calculate the mask for the given level in the tree.
 101  *
 102  * the mask used to index root's children is level 0.
 103  */
 104
 105 static uint64_t
 106 rpst_level2mask(const struct rpst_tree *t, unsigned int level)
 107 {
 108         uint64_t mask;
 109
 110         if (t->t_height < level) {
 111                 mask = 0;
 112         } else {
 113                 mask = UINT64_C(1) << (t->t_height - level);
 114         }
 115         return mask;
 116 }
 117
 118 /*
 119  * rpst_startmask: calculate the mask for the start of a search.
 120  * (ie. the mask for the top-most bit)
 121  */
 122
 123 static uint64_t
 124 rpst_startmask(const struct rpst_tree *t)
 125 {
 126         const uint64_t mask = rpst_level2mask(t, 0);
 127
 128         KASSERT((mask | (mask - 1)) == rpst_height2max(t->t_height));
 129         return mask;
 130 }
 131
 132 /*
 133  * rpst_update_parents: update n_parent of children
 134  */
 135
 136 static inline void
 137 rpst_update_parents(struct rpst_node *n)
 138 {
 139         int i;
 140
 141         for (i = 0; i < 2; i++) {
 142                 if (n->n_children[i] != NULL) {
 143                         n->n_children[i]->n_parent = n;
 144                 }
 145         }
 146 }
 147
 148 /*
 149  * rpst_enlarge_tree: enlarge tree so that 'idx' can be stored
 150  */
 151
 152 static void
 153 rpst_enlarge_tree(struct rpst_tree *t, uint64_t idx)
 154 {
 155
 156         while (idx > rpst_height2max(t->t_height)) {
 157                 struct rpst_node *n = t->t_root;
 158
 159                 if (n != NULL) {
 160                         rpst_remove_node(t, n);
 161                         memset(&n->n_children, 0, sizeof(n->n_children));
 162                         n->n_children[0] = t->t_root;
 163                         t->t_root->n_parent = n;
 164                         t->t_root = n;
 165                         n->n_parent = NULL;
 166                 }
 167                 t->t_height++;
 168         }
 169 }
 170
 171 /*
 172  * rpst_insert_node1: a helper for rpst_insert_node.
 173  */
 174
 175 static struct rpst_node *
 176 rpst_insert_node1(struct rpst_node **where, struct rpst_node *n, uint64_t mask)
 177 {
 178         struct rpst_node *parent;
 179         struct rpst_node *cur;
 180         unsigned int idx;
 181
 182         KASSERT((n->n_x & ((-mask) << 1)) == 0);
 183         parent = NULL;
 184 next:
 185         cur = *where;
 186         if (cur == NULL) {
 187                 n->n_parent = parent;
 188                 memset(&n->n_children, 0, sizeof(n->n_children));
 189                 *where = n;
 190                 return NULL;
 191         }
 192         KASSERT(cur->n_parent == parent);
 193         if (n->n_y == cur->n_y && n->n_x == cur->n_x) {
 194                 return cur;
 195         }
 196         if (n->n_y < cur->n_y) {
 197                 /*
 198                  * swap cur and n.
 199                  * note that n is not in tree.
 200                  */
 201                 memcpy(n->n_children, cur->n_children, sizeof(n->n_children));
 202                 n->n_parent = cur->n_parent;
 203                 rpst_update_parents(n);
 204                 *where = n;
 205                 n = cur;
 206                 cur = *where;
 207         }
 208         KASSERT(*where == cur);
 209         idx = (n->n_x & mask) != 0;
 210         where = &cur->n_children[idx];
 211         parent = cur;
 212         KASSERT((*where) == NULL || ((((*where)->n_x & mask) != 0) == idx));
 213         KASSERT((*where) == NULL || (*where)->n_y >= cur->n_y);
 214         mask >>= 1;
 215         goto next;
 216 }
 217
 218 /*
 219  * rpst_insert_node: insert a node into the tree.
 220  *
 221  * => return NULL on success.
 222  * => if a duplicated node (a node with the same X,Y pair as ours) is found,
 223  *    return the node.  in that case, the tree is intact.
 224  */
 225
 226 struct rpst_node *
 227 rpst_insert_node(struct rpst_tree *t, struct rpst_node *n)
 228 {
 229
 230         rpst_enlarge_tree(t, n->n_x);
 231         return rpst_insert_node1(&t->t_root, n, rpst_startmask(t));
 232 }
 233
 234 /*
 235  * rpst_find_pptr: find a pointer to the given node.
 236  *
 237  * also, return the parent node via parentp.  (NULL for the root node.)
 238  */
 239
 240 static inline struct rpst_node **
 241 rpst_find_pptr(struct rpst_tree *t, struct rpst_node *n,
 242     struct rpst_node **parentp)
 243 {
 244         struct rpst_node * const parent = n->n_parent;
 245         unsigned int i;
 246
 247         *parentp = parent;
 248         if (parent == NULL) {
 249                 return &t->t_root;
 250         }
 251         for (i = 0; i < 2 - 1; i++) {
 252                 if (parent->n_children[i] == n) {
 253                         break;
 254                 }
 255         }
 256         KASSERT(parent->n_children[i] == n);
 257         return &parent->n_children[i];
 258 }
 259
 260 /*
 261  * rpst_remove_node_at: remove a node at *where.
 262  */
 263
 264 static void
 265 rpst_remove_node_at(struct rpst_node *parent, struct rpst_node **where,
 266     struct rpst_node *cur)
 267 {
 268         struct rpst_node *tmp[2];
 269         struct rpst_node *selected;
 270         unsigned int selected_idx = 0; /* XXX gcc */
 271         unsigned int i;
 272
 273         KASSERT(cur != NULL);
 274         KASSERT(parent == cur->n_parent);
 275 next:
 276         selected = NULL;
 277         for (i = 0; i < 2; i++) {
 278                 struct rpst_node *c;
 279
 280                 c = cur->n_children[i];
 281                 KASSERT(c == NULL || c->n_parent == cur);
 282                 if (selected == NULL || (c != NULL && c->n_y < selected->n_y)) {
 283                         selected = c;
 284                         selected_idx = i;
 285                 }
 286         }
 287         /*
 288          * now we have:
 289          *
 290          *      parent
 291          *          \ <- where
 292          *           cur
 293          *           / \
 294          *          A  selected
 295          *              / \
 296          *             B   C
 297          */
 298         *where = selected;
 299         if (selected == NULL) {
 300                 return;
 301         }
 302         /*
 303          * swap selected->n_children and cur->n_children.
 304          */
 305         memcpy(tmp, selected->n_children, sizeof(tmp));
 306         memcpy(selected->n_children, cur->n_children, sizeof(tmp));
 307         memcpy(cur->n_children, tmp, sizeof(tmp));
 308         rpst_update_parents(cur);
 309         rpst_update_parents(selected);
 310         selected->n_parent = parent;
 311         /*
 312          *      parent
 313          *          \ <- where
 314          *          selected
 315          *           / \
 316          *          A  selected
 317          *
 318          *              cur
 319          *              / \
 320          *             B   C
 321          */
 322         where = &selected->n_children[selected_idx];
 323         /*
 324          *      parent
 325          *          \
 326          *          selected
 327          *           / \ <- where
 328          *          A  selected (*)
 329          *
 330          *              cur (**)
 331          *              / \
 332          *             B   C
 333          *
 334          * (*) this 'selected' will be overwritten in the next iteration.
 335          * (**) cur->n_parent is bogus.
 336          */
 337         parent = selected;
 338         goto next;
 339 }
 340
 341 /*
 342  * rpst_remove_node: remove a node from the tree.
 343  */
 344
 345 void
 346 rpst_remove_node(struct rpst_tree *t, struct rpst_node *n)
 347 {
 348         struct rpst_node *parent;
 349         struct rpst_node **where;
 350
 351         where = rpst_find_pptr(t, n, &parent);
 352         rpst_remove_node_at(parent, where, n);
 353 }
 354
 355 static bool __unused
 356 rpst_iterator_match_p(const struct rpst_node *n, const struct rpst_iterator *it)
 357 {
 358
 359         if (n->n_y > it->it_max_y) {
 360                 return false;
 361         }
 362         if (n->n_x < it->it_min_x) {
 363                 return false;
 364         }
 365         if (n->n_x > it->it_max_x) {
 366                 return false;
 367         }
 368         return true;
 369 }
 370
 371 struct rpst_node *
 372 rpst_iterate_first(struct rpst_tree *t, uint64_t max_y, uint64_t min_x,
 373     uint64_t max_x, struct rpst_iterator *it)
 374 {
 375         struct rpst_node *n;
 376
 377         KASSERT(min_x <= max_x);
 378         n = t->t_root;
 379         if (n == NULL || n->n_y > max_y) {
 380                 return NULL;
 381         }
 382         if (rpst_height2max(t->t_height) < min_x) {
 383                 return NULL;
 384         }
 385         it->it_tree = t;
 386         it->it_cur = n;
 387         it->it_idx = (min_x & rpst_startmask(t)) != 0;
 388         it->it_level = 0;
 389         it->it_max_y = max_y;
 390         it->it_min_x = min_x;
 391         it->it_max_x = max_x;
 392         return rpst_iterate_next(it);
 393 }
 394
 395 static inline unsigned int
 396 rpst_node_on_edge_p(const struct rpst_node *n, uint64_t val, uint64_t mask)
 397 {
 398
 399         return ((n->n_x ^ val) & ((-mask) << 1)) == 0;
 400 }
 401
 402 static inline uint64_t
 403 rpst_maxidx(const struct rpst_node *n, uint64_t max_x, uint64_t mask)
 404 {
 405
 406         if (rpst_node_on_edge_p(n, max_x, mask)) {
 407                 return (max_x & mask) != 0;
 408         } else {
 409                 return 1;
 410         }
 411 }
 412
 413 static inline uint64_t
 414 rpst_minidx(const struct rpst_node *n, uint64_t min_x, uint64_t mask)
 415 {
 416
 417         if (rpst_node_on_edge_p(n, min_x, mask)) {
 418                 return (min_x & mask) != 0;
 419         } else {
 420                 return 0;
 421         }
 422 }
 423
 424 struct rpst_node *
 425 rpst_iterate_next(struct rpst_iterator *it)
 426 {
 427         struct rpst_tree *t;
 428         struct rpst_node *n;
 429         struct rpst_node *next;
 430         const uint64_t max_y = it->it_max_y;
 431         const uint64_t min_x = it->it_min_x;
 432         const uint64_t max_x = it->it_max_x;
 433         unsigned int idx;
 434         unsigned int maxidx;
 435         unsigned int level;
 436         uint64_t mask;
 437
 438         t = it->it_tree;
 439         n = it->it_cur;
 440         idx = it->it_idx;
 441         level = it->it_level;
 442         mask = rpst_level2mask(t, level);
 443         maxidx = rpst_maxidx(n, max_x, mask);
 444         KASSERT(n == t->t_root || rpst_iterator_match_p(n, it));
 445 next:
 446         KASSERT(mask == rpst_level2mask(t, level));
 447         KASSERT(idx >= rpst_minidx(n, min_x, mask));
 448         KASSERT(maxidx == rpst_maxidx(n, max_x, mask));
 449         KASSERT(idx <= maxidx + 2);
 450         KASSERT(n != NULL);
 451 #if 0
 452         printf("%s: cur=%p, idx=%u maxidx=%u level=%u mask=%" PRIx64 "\n",
 453             __func__, (void *)n, idx, maxidx, level, mask);
 454 #endif
 455         if (idx == maxidx + 1) { /* visit the current node */
 456                 idx++;
 457                 if (min_x <= n->n_x && n->n_x <= max_x) {
 458                         it->it_cur = n;
 459                         it->it_idx = idx;
 460                         it->it_level = level;
 461                         KASSERT(rpst_iterator_match_p(n, it));
 462                         return n; /* report */
 463                 }
 464                 goto next;
 465         } else if (idx == maxidx + 2) { /* back to the parent */
 466                 struct rpst_node **where;
 467
 468                 where = rpst_find_pptr(t, n, &next);
 469                 if (next == NULL) {
 470                         KASSERT(level == 0);
 471                         KASSERT(t->t_root == n);
 472                         KASSERT(&t->t_root == where);
 473                         return NULL; /* done */
 474                 }
 475                 KASSERT(level > 0);
 476                 level--;
 477                 n = next;
 478                 mask = rpst_level2mask(t, level);
 479                 maxidx = rpst_maxidx(n, max_x, mask);
 480                 idx = where - n->n_children + 1;
 481                 KASSERT(idx < 2 + 1);
 482                 goto next;
 483         }
 484         /* go to a child */
 485         KASSERT(idx < 2);
 486         next = n->n_children[idx];
 487         if (next == NULL || next->n_y > max_y) {
 488                 idx++;
 489                 goto next;
 490         }
 491         KASSERT(next->n_parent == n);
 492         KASSERT(next->n_y >= n->n_y);
 493         level++;
 494         mask >>= 1;
 495         n = next;
 496         idx = rpst_minidx(n, min_x, mask);
 497         maxidx = rpst_maxidx(n, max_x, mask);
 498 #if 0
 499         printf("%s: visit %p idx=%u level=%u mask=%llx\n",
 500             __func__, n, idx, level, mask);
 501 #endif
 502         goto next;
 503 }
 504
 505 #if defined(UNITTEST)
 506 #include <sys/time.h>
 507
 508 #include <inttypes.h>
 509 #include <stdio.h>
 510 #include <stdlib.h>
 511
 512 static void
 513 rpst_dump_node(const struct rpst_node *n, unsigned int depth)
 514 {
 515         unsigned int i;
 516
 517         for (i = 0; i < depth; i++) {
 518                 printf("  ");
 519         }
 520         printf("[%u]", depth);
 521         if (n == NULL) {
 522                 printf("NULL\n");
 523                 return;
 524         }
 525         printf("%p x=%" PRIx64 "(%" PRIu64 ") y=%" PRIx64 "(%" PRIu64 ")\n",
 526             (const void *)n, n->n_x, n->n_x, n->n_y, n->n_y);
 527         for (i = 0; i < 2; i++) {
 528                 rpst_dump_node(n->n_children[i], depth + 1);
 529         }
 530 }
 531
 532 static void
 533 rpst_dump_tree(const struct rpst_tree *t)
 534 {
 535
 536         printf("pst %p height=%u\n", (const void *)t, t->t_height);
 537         rpst_dump_node(t->t_root, 0);
 538 }
 539
 540 struct testnode {
 541         struct rpst_node n;
 542         struct testnode *next;
 543         bool failed;
 544         bool found;
 545 };
 546
 547 struct rpst_tree t;
 548 struct testnode *h = NULL;
 549
 550 static uintmax_t
 551 tvdiff(const struct timeval *tv1, const struct timeval *tv2)
 552 {
 553
 554         return (uintmax_t)tv1->tv_sec * 1000000 + tv1->tv_usec -
 555             tv2->tv_sec * 1000000 - tv2->tv_usec;
 556 }
 557
 558 static unsigned int
 559 query(uint64_t max_y, uint64_t min_x, uint64_t max_x)
 560 {
 561         struct testnode *n;
 562         struct rpst_node *rn;
 563         struct rpst_iterator it;
 564         struct timeval start;
 565         struct timeval end;
 566         unsigned int done;
 567
 568         printf("quering max_y=%" PRIu64 " min_x=%" PRIu64 " max_x=%" PRIu64
 569             "\n",
 570             max_y, min_x, max_x);
 571         done = 0;
 572         gettimeofday(&start, NULL);
 573         for (rn = rpst_iterate_first(&t, max_y, min_x, max_x, &it);
 574             rn != NULL;
 575             rn = rpst_iterate_next(&it)) {
 576                 done++;
 577 #if 0
 578                 printf("found %p x=%" PRIu64 " y=%" PRIu64 "\n",
 579                     (void *)rn, rn->n_x, rn->n_y);
 580 #endif
 581                 n = (void *)rn;
 582                 assert(!n->found);
 583                 n->found = true;
 584         }
 585         gettimeofday(&end, NULL);
 586         printf("%u nodes found in %ju usecs\n", done,
 587             tvdiff(&end, &start));
 588
 589         gettimeofday(&start, NULL);
 590         for (n = h; n != NULL; n = n->next) {
 591                 assert(n->failed ||
 592                     n->found == rpst_iterator_match_p(&n->n, &it));
 593                 n->found = false;
 594         }
 595         gettimeofday(&end, NULL);
 596         printf("(linear search took %ju usecs)\n", tvdiff(&end, &start));
 597         return done;
 598 }
 599
 600 int
 601 main(int argc, char *argv[])
 602 {
 603         struct testnode *n;
 604         unsigned int i;
 605         struct rpst_iterator it;
 606         struct timeval start;
 607         struct timeval end;
 608         uint64_t min_y = UINT64_MAX;
 609         uint64_t max_y = 0;
 610         uint64_t min_x = UINT64_MAX;
 611         uint64_t max_x = 0;
 612         uint64_t w;
 613         unsigned int done;
 614         unsigned int fail;
 615         unsigned int num = 500000;
 616
 617         rpst_init_tree(&t);
 618         rpst_dump_tree(&t);
 619         assert(NULL == rpst_iterate_first(&t, UINT64_MAX, 0, UINT64_MAX, &it));
 620
 621         for (i = 0; i < num; i++) {
 622                 n = malloc(sizeof(*n));
 623                 if (i > 499000) {
 624                         n->n.n_x = 10;
 625                         n->n.n_y = random();
 626                 } else if (i > 400000) {
 627                         n->n.n_x = i;
 628                         n->n.n_y = random();
 629                 } else {
 630                         n->n.n_x = random();
 631                         n->n.n_y = random();
 632                 }
 633                 if (n->n.n_y < min_y) {
 634                         min_y = n->n.n_y;
 635                 }
 636                 if (n->n.n_y > max_y) {
 637                         max_y = n->n.n_y;
 638                 }
 639                 if (n->n.n_x < min_x) {
 640                         min_x = n->n.n_x;
 641                 }
 642                 if (n->n.n_x > max_x) {
 643                         max_x = n->n.n_x;
 644                 }
 645                 n->found = false;
 646                 n->failed = false;
 647                 n->next = h;
 648                 h = n;
 649         }
 650
 651         done = 0;
 652         fail = 0;
 653         gettimeofday(&start, NULL);
 654         for (n = h; n != NULL; n = n->next) {
 655                 struct rpst_node *o;
 656 #if 0
 657                 printf("insert %p x=%" PRIu64 " y=%" PRIu64 "\n",
 658                     n, n->n.n_x, n->n.n_y);
 659 #endif
 660                 o = rpst_insert_node(&t, &n->n);
 661                 if (o == NULL) {
 662                         done++;
 663                 } else {
 664                         n->failed = true;
 665                         fail++;
 666                 }
 667         }
 668         gettimeofday(&end, NULL);
 669         printf("%u nodes inserted and %u insertion failed in %ju usecs\n",
 670             done, fail,
 671             tvdiff(&end, &start));
 672
 673         assert(min_y == 0 || 0 == query(min_y - 1, 0, UINT64_MAX));
 674         assert(max_x == UINT64_MAX ||
 675             0 == query(UINT64_MAX, max_x + 1, UINT64_MAX));
 676         assert(min_x == 0 || 0 == query(UINT64_MAX, 0, min_x - 1));
 677
 678         done = query(max_y, min_x, max_x);
 679         assert(done == num - fail);
 680
 681         done = query(UINT64_MAX, 0, UINT64_MAX);
 682         assert(done == num - fail);
 683
 684         w = max_x - min_x;
 685         query(max_y / 2, min_x, max_x);
 686         query(max_y, min_x + w / 2, max_x);
 687         query(max_y / 2, min_x + w / 2, max_x);
 688         query(max_y / 2, min_x, max_x - w / 2);
 689         query(max_y / 2, min_x + w / 3, max_x - w / 3);
 690         query(max_y - 1, min_x + 1, max_x - 1);
 691         query(UINT64_MAX, 10, 10);
 692
 693         done = 0;
 694         gettimeofday(&start, NULL);
 695         for (n = h; n != NULL; n = n->next) {
 696                 if (n->failed) {
 697                         continue;
 698                 }
 699 #if 0
 700                 printf("remove %p x=%" PRIu64 " y=%" PRIu64 "\n",
 701                     n, n->n.n_x, n->n.n_y);
 702 #endif
 703                 rpst_remove_node(&t, &n->n);
 704                 done++;
 705         }
 706         gettimeofday(&end, NULL);
 707         printf("%u nodes removed in %ju usecs\n", done,
 708             tvdiff(&end, &start));
 709
 710         rpst_dump_tree(&t);
 711 }
 712 #endif /* defined(UNITTEST) */