Commit | Line | Data |
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84d4ea48 JH |
1 | /* pp_sort.c |
2 | * | |
be3c0a43 | 3 | * Copyright (c) 1991-2002, Larry Wall |
84d4ea48 JH |
4 | * |
5 | * You may distribute under the terms of either the GNU General Public | |
6 | * License or the Artistic License, as specified in the README file. | |
7 | * | |
8 | */ | |
9 | ||
10 | /* | |
11 | * ...they shuffled back towards the rear of the line. 'No, not at the | |
12 | * rear!' the slave-driver shouted. 'Three files up. And stay there... | |
13 | */ | |
14 | ||
15 | #include "EXTERN.h" | |
16 | #define PERL_IN_PP_SORT_C | |
17 | #include "perl.h" | |
18 | ||
42165d27 VK |
19 | #if defined(UNDER_CE) |
20 | /* looks like 'small' is reserved word for WINCE (or somesuch)*/ | |
21 | #define small xsmall | |
22 | #endif | |
23 | ||
84d4ea48 JH |
24 | static I32 sortcv(pTHX_ SV *a, SV *b); |
25 | static I32 sortcv_stacked(pTHX_ SV *a, SV *b); | |
26 | static I32 sortcv_xsub(pTHX_ SV *a, SV *b); | |
27 | static I32 sv_ncmp(pTHX_ SV *a, SV *b); | |
28 | static I32 sv_i_ncmp(pTHX_ SV *a, SV *b); | |
29 | static I32 amagic_ncmp(pTHX_ SV *a, SV *b); | |
30 | static I32 amagic_i_ncmp(pTHX_ SV *a, SV *b); | |
31 | static I32 amagic_cmp(pTHX_ SV *a, SV *b); | |
32 | static I32 amagic_cmp_locale(pTHX_ SV *a, SV *b); | |
33 | ||
34 | #define sv_cmp_static Perl_sv_cmp | |
35 | #define sv_cmp_locale_static Perl_sv_cmp_locale | |
36 | ||
045ac317 RGS |
37 | #define SORTHINTS(hintsv) \ |
38 | (((hintsv) = GvSV(gv_fetchpv("sort::hints", GV_ADDMULTI, SVt_IV))), \ | |
39 | (SvIOK(hintsv) ? ((I32)SvIV(hintsv)) : 0)) | |
84d4ea48 | 40 | |
c53fc8a6 JH |
41 | #ifndef SMALLSORT |
42 | #define SMALLSORT (200) | |
43 | #endif | |
44 | ||
84d4ea48 JH |
45 | /* |
46 | * The mergesort implementation is by Peter M. Mcilroy <pmcilroy@lucent.com>. | |
47 | * | |
48 | * The original code was written in conjunction with BSD Computer Software | |
49 | * Research Group at University of California, Berkeley. | |
50 | * | |
51 | * See also: "Optimistic Merge Sort" (SODA '92) | |
52 | * | |
53 | * The integration to Perl is by John P. Linderman <jpl@research.att.com>. | |
54 | * | |
55 | * The code can be distributed under the same terms as Perl itself. | |
56 | * | |
57 | */ | |
58 | ||
84d4ea48 JH |
59 | |
60 | typedef char * aptr; /* pointer for arithmetic on sizes */ | |
61 | typedef SV * gptr; /* pointers in our lists */ | |
62 | ||
63 | /* Binary merge internal sort, with a few special mods | |
64 | ** for the special perl environment it now finds itself in. | |
65 | ** | |
66 | ** Things that were once options have been hotwired | |
67 | ** to values suitable for this use. In particular, we'll always | |
68 | ** initialize looking for natural runs, we'll always produce stable | |
69 | ** output, and we'll always do Peter McIlroy's binary merge. | |
70 | */ | |
71 | ||
72 | /* Pointer types for arithmetic and storage and convenience casts */ | |
73 | ||
74 | #define APTR(P) ((aptr)(P)) | |
75 | #define GPTP(P) ((gptr *)(P)) | |
76 | #define GPPP(P) ((gptr **)(P)) | |
77 | ||
78 | ||
79 | /* byte offset from pointer P to (larger) pointer Q */ | |
80 | #define BYTEOFF(P, Q) (APTR(Q) - APTR(P)) | |
81 | ||
82 | #define PSIZE sizeof(gptr) | |
83 | ||
84 | /* If PSIZE is power of 2, make PSHIFT that power, if that helps */ | |
85 | ||
86 | #ifdef PSHIFT | |
87 | #define PNELEM(P, Q) (BYTEOFF(P,Q) >> (PSHIFT)) | |
88 | #define PNBYTE(N) ((N) << (PSHIFT)) | |
89 | #define PINDEX(P, N) (GPTP(APTR(P) + PNBYTE(N))) | |
90 | #else | |
91 | /* Leave optimization to compiler */ | |
92 | #define PNELEM(P, Q) (GPTP(Q) - GPTP(P)) | |
93 | #define PNBYTE(N) ((N) * (PSIZE)) | |
94 | #define PINDEX(P, N) (GPTP(P) + (N)) | |
95 | #endif | |
96 | ||
97 | /* Pointer into other corresponding to pointer into this */ | |
98 | #define POTHER(P, THIS, OTHER) GPTP(APTR(OTHER) + BYTEOFF(THIS,P)) | |
99 | ||
100 | #define FROMTOUPTO(src, dst, lim) do *dst++ = *src++; while(src<lim) | |
101 | ||
102 | ||
103 | /* Runs are identified by a pointer in the auxilliary list. | |
104 | ** The pointer is at the start of the list, | |
105 | ** and it points to the start of the next list. | |
106 | ** NEXT is used as an lvalue, too. | |
107 | */ | |
108 | ||
109 | #define NEXT(P) (*GPPP(P)) | |
110 | ||
111 | ||
112 | /* PTHRESH is the minimum number of pairs with the same sense to justify | |
113 | ** checking for a run and extending it. Note that PTHRESH counts PAIRS, | |
114 | ** not just elements, so PTHRESH == 8 means a run of 16. | |
115 | */ | |
116 | ||
117 | #define PTHRESH (8) | |
118 | ||
119 | /* RTHRESH is the number of elements in a run that must compare low | |
120 | ** to the low element from the opposing run before we justify | |
121 | ** doing a binary rampup instead of single stepping. | |
122 | ** In random input, N in a row low should only happen with | |
123 | ** probability 2^(1-N), so we can risk that we are dealing | |
124 | ** with orderly input without paying much when we aren't. | |
125 | */ | |
126 | ||
127 | #define RTHRESH (6) | |
128 | ||
129 | ||
130 | /* | |
131 | ** Overview of algorithm and variables. | |
132 | ** The array of elements at list1 will be organized into runs of length 2, | |
133 | ** or runs of length >= 2 * PTHRESH. We only try to form long runs when | |
134 | ** PTHRESH adjacent pairs compare in the same way, suggesting overall order. | |
135 | ** | |
136 | ** Unless otherwise specified, pair pointers address the first of two elements. | |
137 | ** | |
138 | ** b and b+1 are a pair that compare with sense ``sense''. | |
139 | ** b is the ``bottom'' of adjacent pairs that might form a longer run. | |
140 | ** | |
141 | ** p2 parallels b in the list2 array, where runs are defined by | |
142 | ** a pointer chain. | |
143 | ** | |
144 | ** t represents the ``top'' of the adjacent pairs that might extend | |
145 | ** the run beginning at b. Usually, t addresses a pair | |
146 | ** that compares with opposite sense from (b,b+1). | |
147 | ** However, it may also address a singleton element at the end of list1, | |
148 | ** or it may be equal to ``last'', the first element beyond list1. | |
149 | ** | |
150 | ** r addresses the Nth pair following b. If this would be beyond t, | |
151 | ** we back it off to t. Only when r is less than t do we consider the | |
152 | ** run long enough to consider checking. | |
153 | ** | |
154 | ** q addresses a pair such that the pairs at b through q already form a run. | |
155 | ** Often, q will equal b, indicating we only are sure of the pair itself. | |
156 | ** However, a search on the previous cycle may have revealed a longer run, | |
157 | ** so q may be greater than b. | |
158 | ** | |
159 | ** p is used to work back from a candidate r, trying to reach q, | |
160 | ** which would mean b through r would be a run. If we discover such a run, | |
161 | ** we start q at r and try to push it further towards t. | |
162 | ** If b through r is NOT a run, we detect the wrong order at (p-1,p). | |
163 | ** In any event, after the check (if any), we have two main cases. | |
164 | ** | |
165 | ** 1) Short run. b <= q < p <= r <= t. | |
166 | ** b through q is a run (perhaps trivial) | |
167 | ** q through p are uninteresting pairs | |
168 | ** p through r is a run | |
169 | ** | |
170 | ** 2) Long run. b < r <= q < t. | |
171 | ** b through q is a run (of length >= 2 * PTHRESH) | |
172 | ** | |
173 | ** Note that degenerate cases are not only possible, but likely. | |
174 | ** For example, if the pair following b compares with opposite sense, | |
175 | ** then b == q < p == r == t. | |
176 | */ | |
177 | ||
178 | ||
957d8989 | 179 | static IV |
84d4ea48 JH |
180 | dynprep(pTHX_ gptr *list1, gptr *list2, size_t nmemb, SVCOMPARE_t cmp) |
181 | { | |
957d8989 | 182 | I32 sense; |
84d4ea48 JH |
183 | register gptr *b, *p, *q, *t, *p2; |
184 | register gptr c, *last, *r; | |
185 | gptr *savep; | |
957d8989 | 186 | IV runs = 0; |
84d4ea48 JH |
187 | |
188 | b = list1; | |
189 | last = PINDEX(b, nmemb); | |
190 | sense = (cmp(aTHX_ *b, *(b+1)) > 0); | |
191 | for (p2 = list2; b < last; ) { | |
192 | /* We just started, or just reversed sense. | |
193 | ** Set t at end of pairs with the prevailing sense. | |
194 | */ | |
195 | for (p = b+2, t = p; ++p < last; t = ++p) { | |
196 | if ((cmp(aTHX_ *t, *p) > 0) != sense) break; | |
197 | } | |
198 | q = b; | |
199 | /* Having laid out the playing field, look for long runs */ | |
200 | do { | |
201 | p = r = b + (2 * PTHRESH); | |
202 | if (r >= t) p = r = t; /* too short to care about */ | |
203 | else { | |
204 | while (((cmp(aTHX_ *(p-1), *p) > 0) == sense) && | |
205 | ((p -= 2) > q)); | |
206 | if (p <= q) { | |
207 | /* b through r is a (long) run. | |
208 | ** Extend it as far as possible. | |
209 | */ | |
210 | p = q = r; | |
211 | while (((p += 2) < t) && | |
212 | ((cmp(aTHX_ *(p-1), *p) > 0) == sense)) q = p; | |
213 | r = p = q + 2; /* no simple pairs, no after-run */ | |
214 | } | |
215 | } | |
216 | if (q > b) { /* run of greater than 2 at b */ | |
217 | savep = p; | |
218 | p = q += 2; | |
219 | /* pick up singleton, if possible */ | |
220 | if ((p == t) && | |
221 | ((t + 1) == last) && | |
222 | ((cmp(aTHX_ *(p-1), *p) > 0) == sense)) | |
223 | savep = r = p = q = last; | |
957d8989 | 224 | p2 = NEXT(p2) = p2 + (p - b); ++runs; |
84d4ea48 JH |
225 | if (sense) while (b < --p) { |
226 | c = *b; | |
227 | *b++ = *p; | |
228 | *p = c; | |
229 | } | |
230 | p = savep; | |
231 | } | |
232 | while (q < p) { /* simple pairs */ | |
957d8989 | 233 | p2 = NEXT(p2) = p2 + 2; ++runs; |
84d4ea48 JH |
234 | if (sense) { |
235 | c = *q++; | |
236 | *(q-1) = *q; | |
237 | *q++ = c; | |
238 | } else q += 2; | |
239 | } | |
240 | if (((b = p) == t) && ((t+1) == last)) { | |
957d8989 | 241 | NEXT(p2) = p2 + 1; ++runs; |
84d4ea48 JH |
242 | b++; |
243 | } | |
244 | q = r; | |
245 | } while (b < t); | |
246 | sense = !sense; | |
247 | } | |
957d8989 | 248 | return runs; |
84d4ea48 JH |
249 | } |
250 | ||
251 | ||
3fe0b9a9 | 252 | /* The original merge sort, in use since 5.7, was as fast as, or faster than, |
957d8989 | 253 | * qsort on many platforms, but slower than qsort, conspicuously so, |
3fe0b9a9 | 254 | * on others. The most likely explanation was platform-specific |
957d8989 JL |
255 | * differences in cache sizes and relative speeds. |
256 | * | |
257 | * The quicksort divide-and-conquer algorithm guarantees that, as the | |
258 | * problem is subdivided into smaller and smaller parts, the parts | |
259 | * fit into smaller (and faster) caches. So it doesn't matter how | |
260 | * many levels of cache exist, quicksort will "find" them, and, | |
261 | * as long as smaller is faster, take advanatge of them. | |
262 | * | |
3fe0b9a9 | 263 | * By contrast, consider how the original mergesort algorithm worked. |
957d8989 JL |
264 | * Suppose we have five runs (each typically of length 2 after dynprep). |
265 | * | |
266 | * pass base aux | |
267 | * 0 1 2 3 4 5 | |
268 | * 1 12 34 5 | |
269 | * 2 1234 5 | |
270 | * 3 12345 | |
271 | * 4 12345 | |
272 | * | |
273 | * Adjacent pairs are merged in "grand sweeps" through the input. | |
274 | * This means, on pass 1, the records in runs 1 and 2 aren't revisited until | |
275 | * runs 3 and 4 are merged and the runs from run 5 have been copied. | |
276 | * The only cache that matters is one large enough to hold *all* the input. | |
277 | * On some platforms, this may be many times slower than smaller caches. | |
278 | * | |
279 | * The following pseudo-code uses the same basic merge algorithm, | |
280 | * but in a divide-and-conquer way. | |
281 | * | |
282 | * # merge $runs runs at offset $offset of list $list1 into $list2. | |
283 | * # all unmerged runs ($runs == 1) originate in list $base. | |
284 | * sub mgsort2 { | |
285 | * my ($offset, $runs, $base, $list1, $list2) = @_; | |
286 | * | |
287 | * if ($runs == 1) { | |
288 | * if ($list1 is $base) copy run to $list2 | |
289 | * return offset of end of list (or copy) | |
290 | * } else { | |
291 | * $off2 = mgsort2($offset, $runs-($runs/2), $base, $list2, $list1) | |
292 | * mgsort2($off2, $runs/2, $base, $list2, $list1) | |
293 | * merge the adjacent runs at $offset of $list1 into $list2 | |
294 | * return the offset of the end of the merged runs | |
295 | * } | |
296 | * } | |
297 | * mgsort2(0, $runs, $base, $aux, $base); | |
298 | * | |
299 | * For our 5 runs, the tree of calls looks like | |
300 | * | |
301 | * 5 | |
302 | * 3 2 | |
303 | * 2 1 1 1 | |
304 | * 1 1 | |
305 | * | |
306 | * 1 2 3 4 5 | |
307 | * | |
308 | * and the corresponding activity looks like | |
309 | * | |
310 | * copy runs 1 and 2 from base to aux | |
311 | * merge runs 1 and 2 from aux to base | |
312 | * (run 3 is where it belongs, no copy needed) | |
313 | * merge runs 12 and 3 from base to aux | |
314 | * (runs 4 and 5 are where they belong, no copy needed) | |
315 | * merge runs 4 and 5 from base to aux | |
316 | * merge runs 123 and 45 from aux to base | |
317 | * | |
318 | * Note that we merge runs 1 and 2 immediately after copying them, | |
319 | * while they are still likely to be in fast cache. Similarly, | |
320 | * run 3 is merged with run 12 while it still may be lingering in cache. | |
321 | * This implementation should therefore enjoy much of the cache-friendly | |
322 | * behavior that quicksort does. In addition, it does less copying | |
323 | * than the original mergesort implementation (only runs 1 and 2 are copied) | |
324 | * and the "balancing" of merges is better (merged runs comprise more nearly | |
325 | * equal numbers of original runs). | |
326 | * | |
327 | * The actual cache-friendly implementation will use a pseudo-stack | |
328 | * to avoid recursion, and will unroll processing of runs of length 2, | |
329 | * but it is otherwise similar to the recursive implementation. | |
957d8989 JL |
330 | */ |
331 | ||
332 | typedef struct { | |
333 | IV offset; /* offset of 1st of 2 runs at this level */ | |
334 | IV runs; /* how many runs must be combined into 1 */ | |
335 | } off_runs; /* pseudo-stack element */ | |
336 | ||
337 | STATIC void | |
3fe0b9a9 | 338 | S_mergesortsv(pTHX_ gptr *base, size_t nmemb, SVCOMPARE_t cmp) |
957d8989 JL |
339 | { |
340 | IV i, run, runs, offset; | |
341 | I32 sense, level; | |
342 | int iwhich; | |
343 | register gptr *f1, *f2, *t, *b, *p, *tp2, *l1, *l2, *q; | |
344 | gptr *aux, *list1, *list2; | |
345 | gptr *p1; | |
346 | gptr small[SMALLSORT]; | |
347 | gptr *which[3]; | |
348 | off_runs stack[60], *stackp; | |
349 | ||
350 | if (nmemb <= 1) return; /* sorted trivially */ | |
351 | if (nmemb <= SMALLSORT) aux = small; /* use stack for aux array */ | |
352 | else { New(799,aux,nmemb,gptr); } /* allocate auxilliary array */ | |
353 | level = 0; | |
354 | stackp = stack; | |
355 | stackp->runs = dynprep(aTHX_ base, aux, nmemb, cmp); | |
356 | stackp->offset = offset = 0; | |
357 | which[0] = which[2] = base; | |
358 | which[1] = aux; | |
359 | for (;;) { | |
360 | /* On levels where both runs have be constructed (stackp->runs == 0), | |
361 | * merge them, and note the offset of their end, in case the offset | |
362 | * is needed at the next level up. Hop up a level, and, | |
363 | * as long as stackp->runs is 0, keep merging. | |
364 | */ | |
365 | if ((runs = stackp->runs) == 0) { | |
366 | iwhich = level & 1; | |
367 | list1 = which[iwhich]; /* area where runs are now */ | |
368 | list2 = which[++iwhich]; /* area for merged runs */ | |
369 | do { | |
370 | offset = stackp->offset; | |
371 | f1 = p1 = list1 + offset; /* start of first run */ | |
372 | p = tp2 = list2 + offset; /* where merged run will go */ | |
373 | t = NEXT(p); /* where first run ends */ | |
374 | f2 = l1 = POTHER(t, list2, list1); /* ... on the other side */ | |
375 | t = NEXT(t); /* where second runs ends */ | |
376 | l2 = POTHER(t, list2, list1); /* ... on the other side */ | |
377 | offset = PNELEM(list2, t); | |
378 | while (f1 < l1 && f2 < l2) { | |
379 | /* If head 1 is larger than head 2, find ALL the elements | |
380 | ** in list 2 strictly less than head1, write them all, | |
381 | ** then head 1. Then compare the new heads, and repeat, | |
382 | ** until one or both lists are exhausted. | |
383 | ** | |
384 | ** In all comparisons (after establishing | |
385 | ** which head to merge) the item to merge | |
386 | ** (at pointer q) is the first operand of | |
387 | ** the comparison. When we want to know | |
388 | ** if ``q is strictly less than the other'', | |
389 | ** we can't just do | |
390 | ** cmp(q, other) < 0 | |
391 | ** because stability demands that we treat equality | |
392 | ** as high when q comes from l2, and as low when | |
393 | ** q was from l1. So we ask the question by doing | |
394 | ** cmp(q, other) <= sense | |
395 | ** and make sense == 0 when equality should look low, | |
396 | ** and -1 when equality should look high. | |
397 | */ | |
398 | ||
399 | ||
400 | if (cmp(aTHX_ *f1, *f2) <= 0) { | |
401 | q = f2; b = f1; t = l1; | |
402 | sense = -1; | |
403 | } else { | |
404 | q = f1; b = f2; t = l2; | |
405 | sense = 0; | |
406 | } | |
407 | ||
408 | ||
409 | /* ramp up | |
410 | ** | |
411 | ** Leave t at something strictly | |
412 | ** greater than q (or at the end of the list), | |
413 | ** and b at something strictly less than q. | |
414 | */ | |
415 | for (i = 1, run = 0 ;;) { | |
416 | if ((p = PINDEX(b, i)) >= t) { | |
417 | /* off the end */ | |
418 | if (((p = PINDEX(t, -1)) > b) && | |
419 | (cmp(aTHX_ *q, *p) <= sense)) | |
420 | t = p; | |
421 | else b = p; | |
422 | break; | |
423 | } else if (cmp(aTHX_ *q, *p) <= sense) { | |
424 | t = p; | |
425 | break; | |
426 | } else b = p; | |
427 | if (++run >= RTHRESH) i += i; | |
428 | } | |
429 | ||
430 | ||
431 | /* q is known to follow b and must be inserted before t. | |
432 | ** Increment b, so the range of possibilities is [b,t). | |
433 | ** Round binary split down, to favor early appearance. | |
434 | ** Adjust b and t until q belongs just before t. | |
435 | */ | |
436 | ||
437 | b++; | |
438 | while (b < t) { | |
439 | p = PINDEX(b, (PNELEM(b, t) - 1) / 2); | |
440 | if (cmp(aTHX_ *q, *p) <= sense) { | |
441 | t = p; | |
442 | } else b = p + 1; | |
443 | } | |
444 | ||
445 | ||
446 | /* Copy all the strictly low elements */ | |
447 | ||
448 | if (q == f1) { | |
449 | FROMTOUPTO(f2, tp2, t); | |
450 | *tp2++ = *f1++; | |
451 | } else { | |
452 | FROMTOUPTO(f1, tp2, t); | |
453 | *tp2++ = *f2++; | |
454 | } | |
455 | } | |
456 | ||
457 | ||
458 | /* Run out remaining list */ | |
459 | if (f1 == l1) { | |
460 | if (f2 < l2) FROMTOUPTO(f2, tp2, l2); | |
461 | } else FROMTOUPTO(f1, tp2, l1); | |
462 | p1 = NEXT(p1) = POTHER(tp2, list2, list1); | |
463 | ||
464 | if (--level == 0) goto done; | |
465 | --stackp; | |
466 | t = list1; list1 = list2; list2 = t; /* swap lists */ | |
467 | } while ((runs = stackp->runs) == 0); | |
468 | } | |
469 | ||
470 | ||
471 | stackp->runs = 0; /* current run will finish level */ | |
472 | /* While there are more than 2 runs remaining, | |
473 | * turn them into exactly 2 runs (at the "other" level), | |
474 | * each made up of approximately half the runs. | |
475 | * Stack the second half for later processing, | |
476 | * and set about producing the first half now. | |
477 | */ | |
478 | while (runs > 2) { | |
479 | ++level; | |
480 | ++stackp; | |
481 | stackp->offset = offset; | |
482 | runs -= stackp->runs = runs / 2; | |
483 | } | |
484 | /* We must construct a single run from 1 or 2 runs. | |
485 | * All the original runs are in which[0] == base. | |
486 | * The run we construct must end up in which[level&1]. | |
487 | */ | |
488 | iwhich = level & 1; | |
489 | if (runs == 1) { | |
490 | /* Constructing a single run from a single run. | |
491 | * If it's where it belongs already, there's nothing to do. | |
492 | * Otherwise, copy it to where it belongs. | |
493 | * A run of 1 is either a singleton at level 0, | |
494 | * or the second half of a split 3. In neither event | |
495 | * is it necessary to set offset. It will be set by the merge | |
496 | * that immediately follows. | |
497 | */ | |
498 | if (iwhich) { /* Belongs in aux, currently in base */ | |
499 | f1 = b = PINDEX(base, offset); /* where list starts */ | |
500 | f2 = PINDEX(aux, offset); /* where list goes */ | |
501 | t = NEXT(f2); /* where list will end */ | |
502 | offset = PNELEM(aux, t); /* offset thereof */ | |
503 | t = PINDEX(base, offset); /* where it currently ends */ | |
504 | FROMTOUPTO(f1, f2, t); /* copy */ | |
505 | NEXT(b) = t; /* set up parallel pointer */ | |
506 | } else if (level == 0) goto done; /* single run at level 0 */ | |
507 | } else { | |
508 | /* Constructing a single run from two runs. | |
509 | * The merge code at the top will do that. | |
510 | * We need only make sure the two runs are in the "other" array, | |
511 | * so they'll end up in the correct array after the merge. | |
512 | */ | |
513 | ++level; | |
514 | ++stackp; | |
515 | stackp->offset = offset; | |
516 | stackp->runs = 0; /* take care of both runs, trigger merge */ | |
517 | if (!iwhich) { /* Merged runs belong in aux, copy 1st */ | |
518 | f1 = b = PINDEX(base, offset); /* where first run starts */ | |
519 | f2 = PINDEX(aux, offset); /* where it will be copied */ | |
520 | t = NEXT(f2); /* where first run will end */ | |
521 | offset = PNELEM(aux, t); /* offset thereof */ | |
522 | p = PINDEX(base, offset); /* end of first run */ | |
523 | t = NEXT(t); /* where second run will end */ | |
524 | t = PINDEX(base, PNELEM(aux, t)); /* where it now ends */ | |
525 | FROMTOUPTO(f1, f2, t); /* copy both runs */ | |
526 | NEXT(b) = p; /* paralled pointer for 1st */ | |
527 | NEXT(p) = t; /* ... and for second */ | |
528 | } | |
529 | } | |
530 | } | |
531 | done: | |
532 | if (aux != small) Safefree(aux); /* free iff allocated */ | |
533 | return; | |
534 | } | |
535 | ||
84d4ea48 JH |
536 | /* |
537 | * The quicksort implementation was derived from source code contributed | |
538 | * by Tom Horsley. | |
539 | * | |
540 | * NOTE: this code was derived from Tom Horsley's qsort replacement | |
541 | * and should not be confused with the original code. | |
542 | */ | |
543 | ||
544 | /* Copyright (C) Tom Horsley, 1997. All rights reserved. | |
545 | ||
546 | Permission granted to distribute under the same terms as perl which are | |
547 | (briefly): | |
548 | ||
549 | This program is free software; you can redistribute it and/or modify | |
550 | it under the terms of either: | |
551 | ||
552 | a) the GNU General Public License as published by the Free | |
553 | Software Foundation; either version 1, or (at your option) any | |
554 | later version, or | |
555 | ||
556 | b) the "Artistic License" which comes with this Kit. | |
557 | ||
558 | Details on the perl license can be found in the perl source code which | |
559 | may be located via the www.perl.com web page. | |
560 | ||
561 | This is the most wonderfulest possible qsort I can come up with (and | |
562 | still be mostly portable) My (limited) tests indicate it consistently | |
563 | does about 20% fewer calls to compare than does the qsort in the Visual | |
564 | C++ library, other vendors may vary. | |
565 | ||
566 | Some of the ideas in here can be found in "Algorithms" by Sedgewick, | |
567 | others I invented myself (or more likely re-invented since they seemed | |
568 | pretty obvious once I watched the algorithm operate for a while). | |
569 | ||
570 | Most of this code was written while watching the Marlins sweep the Giants | |
571 | in the 1997 National League Playoffs - no Braves fans allowed to use this | |
572 | code (just kidding :-). | |
573 | ||
574 | I realize that if I wanted to be true to the perl tradition, the only | |
575 | comment in this file would be something like: | |
576 | ||
577 | ...they shuffled back towards the rear of the line. 'No, not at the | |
578 | rear!' the slave-driver shouted. 'Three files up. And stay there... | |
579 | ||
580 | However, I really needed to violate that tradition just so I could keep | |
581 | track of what happens myself, not to mention some poor fool trying to | |
582 | understand this years from now :-). | |
583 | */ | |
584 | ||
585 | /* ********************************************************** Configuration */ | |
586 | ||
587 | #ifndef QSORT_ORDER_GUESS | |
588 | #define QSORT_ORDER_GUESS 2 /* Select doubling version of the netBSD trick */ | |
589 | #endif | |
590 | ||
591 | /* QSORT_MAX_STACK is the largest number of partitions that can be stacked up for | |
592 | future processing - a good max upper bound is log base 2 of memory size | |
593 | (32 on 32 bit machines, 64 on 64 bit machines, etc). In reality can | |
594 | safely be smaller than that since the program is taking up some space and | |
595 | most operating systems only let you grab some subset of contiguous | |
596 | memory (not to mention that you are normally sorting data larger than | |
597 | 1 byte element size :-). | |
598 | */ | |
599 | #ifndef QSORT_MAX_STACK | |
600 | #define QSORT_MAX_STACK 32 | |
601 | #endif | |
602 | ||
603 | /* QSORT_BREAK_EVEN is the size of the largest partition we should insertion sort. | |
604 | Anything bigger and we use qsort. If you make this too small, the qsort | |
605 | will probably break (or become less efficient), because it doesn't expect | |
606 | the middle element of a partition to be the same as the right or left - | |
607 | you have been warned). | |
608 | */ | |
609 | #ifndef QSORT_BREAK_EVEN | |
610 | #define QSORT_BREAK_EVEN 6 | |
611 | #endif | |
612 | ||
4eb872f6 JL |
613 | /* QSORT_PLAY_SAFE is the size of the largest partition we're willing |
614 | to go quadratic on. We innoculate larger partitions against | |
615 | quadratic behavior by shuffling them before sorting. This is not | |
616 | an absolute guarantee of non-quadratic behavior, but it would take | |
617 | staggeringly bad luck to pick extreme elements as the pivot | |
618 | from randomized data. | |
619 | */ | |
620 | #ifndef QSORT_PLAY_SAFE | |
621 | #define QSORT_PLAY_SAFE 255 | |
622 | #endif | |
623 | ||
84d4ea48 JH |
624 | /* ************************************************************* Data Types */ |
625 | ||
626 | /* hold left and right index values of a partition waiting to be sorted (the | |
627 | partition includes both left and right - right is NOT one past the end or | |
628 | anything like that). | |
629 | */ | |
630 | struct partition_stack_entry { | |
631 | int left; | |
632 | int right; | |
633 | #ifdef QSORT_ORDER_GUESS | |
634 | int qsort_break_even; | |
635 | #endif | |
636 | }; | |
637 | ||
638 | /* ******************************************************* Shorthand Macros */ | |
639 | ||
640 | /* Note that these macros will be used from inside the qsort function where | |
641 | we happen to know that the variable 'elt_size' contains the size of an | |
642 | array element and the variable 'temp' points to enough space to hold a | |
643 | temp element and the variable 'array' points to the array being sorted | |
644 | and 'compare' is the pointer to the compare routine. | |
645 | ||
646 | Also note that there are very many highly architecture specific ways | |
647 | these might be sped up, but this is simply the most generally portable | |
648 | code I could think of. | |
649 | */ | |
650 | ||
651 | /* Return < 0 == 0 or > 0 as the value of elt1 is < elt2, == elt2, > elt2 | |
652 | */ | |
653 | #define qsort_cmp(elt1, elt2) \ | |
654 | ((*compare)(aTHX_ array[elt1], array[elt2])) | |
655 | ||
656 | #ifdef QSORT_ORDER_GUESS | |
657 | #define QSORT_NOTICE_SWAP swapped++; | |
658 | #else | |
659 | #define QSORT_NOTICE_SWAP | |
660 | #endif | |
661 | ||
662 | /* swaps contents of array elements elt1, elt2. | |
663 | */ | |
664 | #define qsort_swap(elt1, elt2) \ | |
665 | STMT_START { \ | |
666 | QSORT_NOTICE_SWAP \ | |
667 | temp = array[elt1]; \ | |
668 | array[elt1] = array[elt2]; \ | |
669 | array[elt2] = temp; \ | |
670 | } STMT_END | |
671 | ||
672 | /* rotate contents of elt1, elt2, elt3 such that elt1 gets elt2, elt2 gets | |
673 | elt3 and elt3 gets elt1. | |
674 | */ | |
675 | #define qsort_rotate(elt1, elt2, elt3) \ | |
676 | STMT_START { \ | |
677 | QSORT_NOTICE_SWAP \ | |
678 | temp = array[elt1]; \ | |
679 | array[elt1] = array[elt2]; \ | |
680 | array[elt2] = array[elt3]; \ | |
681 | array[elt3] = temp; \ | |
682 | } STMT_END | |
683 | ||
684 | /* ************************************************************ Debug stuff */ | |
685 | ||
686 | #ifdef QSORT_DEBUG | |
687 | ||
688 | static void | |
689 | break_here() | |
690 | { | |
691 | return; /* good place to set a breakpoint */ | |
692 | } | |
693 | ||
694 | #define qsort_assert(t) (void)( (t) || (break_here(), 0) ) | |
695 | ||
696 | static void | |
697 | doqsort_all_asserts( | |
698 | void * array, | |
699 | size_t num_elts, | |
700 | size_t elt_size, | |
701 | int (*compare)(const void * elt1, const void * elt2), | |
702 | int pc_left, int pc_right, int u_left, int u_right) | |
703 | { | |
704 | int i; | |
705 | ||
706 | qsort_assert(pc_left <= pc_right); | |
707 | qsort_assert(u_right < pc_left); | |
708 | qsort_assert(pc_right < u_left); | |
709 | for (i = u_right + 1; i < pc_left; ++i) { | |
710 | qsort_assert(qsort_cmp(i, pc_left) < 0); | |
711 | } | |
712 | for (i = pc_left; i < pc_right; ++i) { | |
713 | qsort_assert(qsort_cmp(i, pc_right) == 0); | |
714 | } | |
715 | for (i = pc_right + 1; i < u_left; ++i) { | |
716 | qsort_assert(qsort_cmp(pc_right, i) < 0); | |
717 | } | |
718 | } | |
719 | ||
720 | #define qsort_all_asserts(PC_LEFT, PC_RIGHT, U_LEFT, U_RIGHT) \ | |
721 | doqsort_all_asserts(array, num_elts, elt_size, compare, \ | |
722 | PC_LEFT, PC_RIGHT, U_LEFT, U_RIGHT) | |
723 | ||
724 | #else | |
725 | ||
726 | #define qsort_assert(t) ((void)0) | |
727 | ||
728 | #define qsort_all_asserts(PC_LEFT, PC_RIGHT, U_LEFT, U_RIGHT) ((void)0) | |
729 | ||
730 | #endif | |
731 | ||
732 | /* ****************************************************************** qsort */ | |
733 | ||
734 | STATIC void /* the standard unstable (u) quicksort (qsort) */ | |
735 | S_qsortsvu(pTHX_ SV ** array, size_t num_elts, SVCOMPARE_t compare) | |
736 | { | |
737 | register SV * temp; | |
738 | ||
739 | struct partition_stack_entry partition_stack[QSORT_MAX_STACK]; | |
740 | int next_stack_entry = 0; | |
741 | ||
742 | int part_left; | |
743 | int part_right; | |
744 | #ifdef QSORT_ORDER_GUESS | |
745 | int qsort_break_even; | |
746 | int swapped; | |
747 | #endif | |
748 | ||
749 | /* Make sure we actually have work to do. | |
750 | */ | |
751 | if (num_elts <= 1) { | |
752 | return; | |
753 | } | |
754 | ||
4eb872f6 JL |
755 | /* Innoculate large partitions against quadratic behavior */ |
756 | if (num_elts > QSORT_PLAY_SAFE) { | |
757 | register size_t n, j; | |
758 | register SV **q; | |
759 | for (n = num_elts, q = array; n > 1; ) { | |
eb160463 | 760 | j = (size_t)(n-- * Drand01()); |
4eb872f6 JL |
761 | temp = q[j]; |
762 | q[j] = q[n]; | |
763 | q[n] = temp; | |
764 | } | |
765 | } | |
766 | ||
84d4ea48 JH |
767 | /* Setup the initial partition definition and fall into the sorting loop |
768 | */ | |
769 | part_left = 0; | |
770 | part_right = (int)(num_elts - 1); | |
771 | #ifdef QSORT_ORDER_GUESS | |
772 | qsort_break_even = QSORT_BREAK_EVEN; | |
773 | #else | |
774 | #define qsort_break_even QSORT_BREAK_EVEN | |
775 | #endif | |
776 | for ( ; ; ) { | |
777 | if ((part_right - part_left) >= qsort_break_even) { | |
778 | /* OK, this is gonna get hairy, so lets try to document all the | |
779 | concepts and abbreviations and variables and what they keep | |
780 | track of: | |
781 | ||
782 | pc: pivot chunk - the set of array elements we accumulate in the | |
783 | middle of the partition, all equal in value to the original | |
784 | pivot element selected. The pc is defined by: | |
785 | ||
786 | pc_left - the leftmost array index of the pc | |
787 | pc_right - the rightmost array index of the pc | |
788 | ||
789 | we start with pc_left == pc_right and only one element | |
790 | in the pivot chunk (but it can grow during the scan). | |
791 | ||
792 | u: uncompared elements - the set of elements in the partition | |
793 | we have not yet compared to the pivot value. There are two | |
794 | uncompared sets during the scan - one to the left of the pc | |
795 | and one to the right. | |
796 | ||
797 | u_right - the rightmost index of the left side's uncompared set | |
798 | u_left - the leftmost index of the right side's uncompared set | |
799 | ||
800 | The leftmost index of the left sides's uncompared set | |
801 | doesn't need its own variable because it is always defined | |
802 | by the leftmost edge of the whole partition (part_left). The | |
803 | same goes for the rightmost edge of the right partition | |
804 | (part_right). | |
805 | ||
806 | We know there are no uncompared elements on the left once we | |
807 | get u_right < part_left and no uncompared elements on the | |
808 | right once u_left > part_right. When both these conditions | |
809 | are met, we have completed the scan of the partition. | |
810 | ||
811 | Any elements which are between the pivot chunk and the | |
812 | uncompared elements should be less than the pivot value on | |
813 | the left side and greater than the pivot value on the right | |
814 | side (in fact, the goal of the whole algorithm is to arrange | |
815 | for that to be true and make the groups of less-than and | |
816 | greater-then elements into new partitions to sort again). | |
817 | ||
818 | As you marvel at the complexity of the code and wonder why it | |
819 | has to be so confusing. Consider some of the things this level | |
820 | of confusion brings: | |
821 | ||
822 | Once I do a compare, I squeeze every ounce of juice out of it. I | |
823 | never do compare calls I don't have to do, and I certainly never | |
824 | do redundant calls. | |
825 | ||
826 | I also never swap any elements unless I can prove there is a | |
827 | good reason. Many sort algorithms will swap a known value with | |
828 | an uncompared value just to get things in the right place (or | |
829 | avoid complexity :-), but that uncompared value, once it gets | |
830 | compared, may then have to be swapped again. A lot of the | |
831 | complexity of this code is due to the fact that it never swaps | |
832 | anything except compared values, and it only swaps them when the | |
833 | compare shows they are out of position. | |
834 | */ | |
835 | int pc_left, pc_right; | |
836 | int u_right, u_left; | |
837 | ||
838 | int s; | |
839 | ||
840 | pc_left = ((part_left + part_right) / 2); | |
841 | pc_right = pc_left; | |
842 | u_right = pc_left - 1; | |
843 | u_left = pc_right + 1; | |
844 | ||
845 | /* Qsort works best when the pivot value is also the median value | |
846 | in the partition (unfortunately you can't find the median value | |
847 | without first sorting :-), so to give the algorithm a helping | |
848 | hand, we pick 3 elements and sort them and use the median value | |
849 | of that tiny set as the pivot value. | |
850 | ||
851 | Some versions of qsort like to use the left middle and right as | |
852 | the 3 elements to sort so they can insure the ends of the | |
853 | partition will contain values which will stop the scan in the | |
854 | compare loop, but when you have to call an arbitrarily complex | |
855 | routine to do a compare, its really better to just keep track of | |
856 | array index values to know when you hit the edge of the | |
857 | partition and avoid the extra compare. An even better reason to | |
858 | avoid using a compare call is the fact that you can drop off the | |
859 | edge of the array if someone foolishly provides you with an | |
860 | unstable compare function that doesn't always provide consistent | |
861 | results. | |
862 | ||
863 | So, since it is simpler for us to compare the three adjacent | |
864 | elements in the middle of the partition, those are the ones we | |
865 | pick here (conveniently pointed at by u_right, pc_left, and | |
866 | u_left). The values of the left, center, and right elements | |
867 | are refered to as l c and r in the following comments. | |
868 | */ | |
869 | ||
870 | #ifdef QSORT_ORDER_GUESS | |
871 | swapped = 0; | |
872 | #endif | |
873 | s = qsort_cmp(u_right, pc_left); | |
874 | if (s < 0) { | |
875 | /* l < c */ | |
876 | s = qsort_cmp(pc_left, u_left); | |
877 | /* if l < c, c < r - already in order - nothing to do */ | |
878 | if (s == 0) { | |
879 | /* l < c, c == r - already in order, pc grows */ | |
880 | ++pc_right; | |
881 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
882 | } else if (s > 0) { | |
883 | /* l < c, c > r - need to know more */ | |
884 | s = qsort_cmp(u_right, u_left); | |
885 | if (s < 0) { | |
886 | /* l < c, c > r, l < r - swap c & r to get ordered */ | |
887 | qsort_swap(pc_left, u_left); | |
888 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
889 | } else if (s == 0) { | |
890 | /* l < c, c > r, l == r - swap c&r, grow pc */ | |
891 | qsort_swap(pc_left, u_left); | |
892 | --pc_left; | |
893 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
894 | } else { | |
895 | /* l < c, c > r, l > r - make lcr into rlc to get ordered */ | |
896 | qsort_rotate(pc_left, u_right, u_left); | |
897 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
898 | } | |
899 | } | |
900 | } else if (s == 0) { | |
901 | /* l == c */ | |
902 | s = qsort_cmp(pc_left, u_left); | |
903 | if (s < 0) { | |
904 | /* l == c, c < r - already in order, grow pc */ | |
905 | --pc_left; | |
906 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
907 | } else if (s == 0) { | |
908 | /* l == c, c == r - already in order, grow pc both ways */ | |
909 | --pc_left; | |
910 | ++pc_right; | |
911 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
912 | } else { | |
913 | /* l == c, c > r - swap l & r, grow pc */ | |
914 | qsort_swap(u_right, u_left); | |
915 | ++pc_right; | |
916 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
917 | } | |
918 | } else { | |
919 | /* l > c */ | |
920 | s = qsort_cmp(pc_left, u_left); | |
921 | if (s < 0) { | |
922 | /* l > c, c < r - need to know more */ | |
923 | s = qsort_cmp(u_right, u_left); | |
924 | if (s < 0) { | |
925 | /* l > c, c < r, l < r - swap l & c to get ordered */ | |
926 | qsort_swap(u_right, pc_left); | |
927 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
928 | } else if (s == 0) { | |
929 | /* l > c, c < r, l == r - swap l & c, grow pc */ | |
930 | qsort_swap(u_right, pc_left); | |
931 | ++pc_right; | |
932 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
933 | } else { | |
934 | /* l > c, c < r, l > r - rotate lcr into crl to order */ | |
935 | qsort_rotate(u_right, pc_left, u_left); | |
936 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
937 | } | |
938 | } else if (s == 0) { | |
939 | /* l > c, c == r - swap ends, grow pc */ | |
940 | qsort_swap(u_right, u_left); | |
941 | --pc_left; | |
942 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
943 | } else { | |
944 | /* l > c, c > r - swap ends to get in order */ | |
945 | qsort_swap(u_right, u_left); | |
946 | qsort_all_asserts(pc_left, pc_right, u_left + 1, u_right - 1); | |
947 | } | |
948 | } | |
949 | /* We now know the 3 middle elements have been compared and | |
950 | arranged in the desired order, so we can shrink the uncompared | |
951 | sets on both sides | |
952 | */ | |
953 | --u_right; | |
954 | ++u_left; | |
955 | qsort_all_asserts(pc_left, pc_right, u_left, u_right); | |
956 | ||
957 | /* The above massive nested if was the simple part :-). We now have | |
958 | the middle 3 elements ordered and we need to scan through the | |
959 | uncompared sets on either side, swapping elements that are on | |
960 | the wrong side or simply shuffling equal elements around to get | |
961 | all equal elements into the pivot chunk. | |
962 | */ | |
963 | ||
964 | for ( ; ; ) { | |
965 | int still_work_on_left; | |
966 | int still_work_on_right; | |
967 | ||
968 | /* Scan the uncompared values on the left. If I find a value | |
969 | equal to the pivot value, move it over so it is adjacent to | |
970 | the pivot chunk and expand the pivot chunk. If I find a value | |
971 | less than the pivot value, then just leave it - its already | |
972 | on the correct side of the partition. If I find a greater | |
973 | value, then stop the scan. | |
974 | */ | |
975 | while ((still_work_on_left = (u_right >= part_left))) { | |
976 | s = qsort_cmp(u_right, pc_left); | |
977 | if (s < 0) { | |
978 | --u_right; | |
979 | } else if (s == 0) { | |
980 | --pc_left; | |
981 | if (pc_left != u_right) { | |
982 | qsort_swap(u_right, pc_left); | |
983 | } | |
984 | --u_right; | |
985 | } else { | |
986 | break; | |
987 | } | |
988 | qsort_assert(u_right < pc_left); | |
989 | qsort_assert(pc_left <= pc_right); | |
990 | qsort_assert(qsort_cmp(u_right + 1, pc_left) <= 0); | |
991 | qsort_assert(qsort_cmp(pc_left, pc_right) == 0); | |
992 | } | |
993 | ||
994 | /* Do a mirror image scan of uncompared values on the right | |
995 | */ | |
996 | while ((still_work_on_right = (u_left <= part_right))) { | |
997 | s = qsort_cmp(pc_right, u_left); | |
998 | if (s < 0) { | |
999 | ++u_left; | |
1000 | } else if (s == 0) { | |
1001 | ++pc_right; | |
1002 | if (pc_right != u_left) { | |
1003 | qsort_swap(pc_right, u_left); | |
1004 | } | |
1005 | ++u_left; | |
1006 | } else { | |
1007 | break; | |
1008 | } | |
1009 | qsort_assert(u_left > pc_right); | |
1010 | qsort_assert(pc_left <= pc_right); | |
1011 | qsort_assert(qsort_cmp(pc_right, u_left - 1) <= 0); | |
1012 | qsort_assert(qsort_cmp(pc_left, pc_right) == 0); | |
1013 | } | |
1014 | ||
1015 | if (still_work_on_left) { | |
1016 | /* I know I have a value on the left side which needs to be | |
1017 | on the right side, but I need to know more to decide | |
1018 | exactly the best thing to do with it. | |
1019 | */ | |
1020 | if (still_work_on_right) { | |
1021 | /* I know I have values on both side which are out of | |
1022 | position. This is a big win because I kill two birds | |
1023 | with one swap (so to speak). I can advance the | |
1024 | uncompared pointers on both sides after swapping both | |
1025 | of them into the right place. | |
1026 | */ | |
1027 | qsort_swap(u_right, u_left); | |
1028 | --u_right; | |
1029 | ++u_left; | |
1030 | qsort_all_asserts(pc_left, pc_right, u_left, u_right); | |
1031 | } else { | |
1032 | /* I have an out of position value on the left, but the | |
1033 | right is fully scanned, so I "slide" the pivot chunk | |
1034 | and any less-than values left one to make room for the | |
1035 | greater value over on the right. If the out of position | |
1036 | value is immediately adjacent to the pivot chunk (there | |
1037 | are no less-than values), I can do that with a swap, | |
1038 | otherwise, I have to rotate one of the less than values | |
1039 | into the former position of the out of position value | |
1040 | and the right end of the pivot chunk into the left end | |
1041 | (got all that?). | |
1042 | */ | |
1043 | --pc_left; | |
1044 | if (pc_left == u_right) { | |
1045 | qsort_swap(u_right, pc_right); | |
1046 | qsort_all_asserts(pc_left, pc_right-1, u_left, u_right-1); | |
1047 | } else { | |
1048 | qsort_rotate(u_right, pc_left, pc_right); | |
1049 | qsort_all_asserts(pc_left, pc_right-1, u_left, u_right-1); | |
1050 | } | |
1051 | --pc_right; | |
1052 | --u_right; | |
1053 | } | |
1054 | } else if (still_work_on_right) { | |
1055 | /* Mirror image of complex case above: I have an out of | |
1056 | position value on the right, but the left is fully | |
1057 | scanned, so I need to shuffle things around to make room | |
1058 | for the right value on the left. | |
1059 | */ | |
1060 | ++pc_right; | |
1061 | if (pc_right == u_left) { | |
1062 | qsort_swap(u_left, pc_left); | |
1063 | qsort_all_asserts(pc_left+1, pc_right, u_left+1, u_right); | |
1064 | } else { | |
1065 | qsort_rotate(pc_right, pc_left, u_left); | |
1066 | qsort_all_asserts(pc_left+1, pc_right, u_left+1, u_right); | |
1067 | } | |
1068 | ++pc_left; | |
1069 | ++u_left; | |
1070 | } else { | |
1071 | /* No more scanning required on either side of partition, | |
1072 | break out of loop and figure out next set of partitions | |
1073 | */ | |
1074 | break; | |
1075 | } | |
1076 | } | |
1077 | ||
1078 | /* The elements in the pivot chunk are now in the right place. They | |
1079 | will never move or be compared again. All I have to do is decide | |
1080 | what to do with the stuff to the left and right of the pivot | |
1081 | chunk. | |
1082 | ||
1083 | Notes on the QSORT_ORDER_GUESS ifdef code: | |
1084 | ||
1085 | 1. If I just built these partitions without swapping any (or | |
1086 | very many) elements, there is a chance that the elements are | |
1087 | already ordered properly (being properly ordered will | |
1088 | certainly result in no swapping, but the converse can't be | |
1089 | proved :-). | |
1090 | ||
1091 | 2. A (properly written) insertion sort will run faster on | |
1092 | already ordered data than qsort will. | |
1093 | ||
1094 | 3. Perhaps there is some way to make a good guess about | |
1095 | switching to an insertion sort earlier than partition size 6 | |
1096 | (for instance - we could save the partition size on the stack | |
1097 | and increase the size each time we find we didn't swap, thus | |
1098 | switching to insertion sort earlier for partitions with a | |
1099 | history of not swapping). | |
1100 | ||
1101 | 4. Naturally, if I just switch right away, it will make | |
1102 | artificial benchmarks with pure ascending (or descending) | |
1103 | data look really good, but is that a good reason in general? | |
1104 | Hard to say... | |
1105 | */ | |
1106 | ||
1107 | #ifdef QSORT_ORDER_GUESS | |
1108 | if (swapped < 3) { | |
1109 | #if QSORT_ORDER_GUESS == 1 | |
1110 | qsort_break_even = (part_right - part_left) + 1; | |
1111 | #endif | |
1112 | #if QSORT_ORDER_GUESS == 2 | |
1113 | qsort_break_even *= 2; | |
1114 | #endif | |
1115 | #if QSORT_ORDER_GUESS == 3 | |
1116 | int prev_break = qsort_break_even; | |
1117 | qsort_break_even *= qsort_break_even; | |
1118 | if (qsort_break_even < prev_break) { | |
1119 | qsort_break_even = (part_right - part_left) + 1; | |
1120 | } | |
1121 | #endif | |
1122 | } else { | |
1123 | qsort_break_even = QSORT_BREAK_EVEN; | |
1124 | } | |
1125 | #endif | |
1126 | ||
1127 | if (part_left < pc_left) { | |
1128 | /* There are elements on the left which need more processing. | |
1129 | Check the right as well before deciding what to do. | |
1130 | */ | |
1131 | if (pc_right < part_right) { | |
1132 | /* We have two partitions to be sorted. Stack the biggest one | |
1133 | and process the smallest one on the next iteration. This | |
1134 | minimizes the stack height by insuring that any additional | |
1135 | stack entries must come from the smallest partition which | |
1136 | (because it is smallest) will have the fewest | |
1137 | opportunities to generate additional stack entries. | |
1138 | */ | |
1139 | if ((part_right - pc_right) > (pc_left - part_left)) { | |
1140 | /* stack the right partition, process the left */ | |
1141 | partition_stack[next_stack_entry].left = pc_right + 1; | |
1142 | partition_stack[next_stack_entry].right = part_right; | |
1143 | #ifdef QSORT_ORDER_GUESS | |
1144 | partition_stack[next_stack_entry].qsort_break_even = qsort_break_even; | |
1145 | #endif | |
1146 | part_right = pc_left - 1; | |
1147 | } else { | |
1148 | /* stack the left partition, process the right */ | |
1149 | partition_stack[next_stack_entry].left = part_left; | |
1150 | partition_stack[next_stack_entry].right = pc_left - 1; | |
1151 | #ifdef QSORT_ORDER_GUESS | |
1152 | partition_stack[next_stack_entry].qsort_break_even = qsort_break_even; | |
1153 | #endif | |
1154 | part_left = pc_right + 1; | |
1155 | } | |
1156 | qsort_assert(next_stack_entry < QSORT_MAX_STACK); | |
1157 | ++next_stack_entry; | |
1158 | } else { | |
1159 | /* The elements on the left are the only remaining elements | |
1160 | that need sorting, arrange for them to be processed as the | |
1161 | next partition. | |
1162 | */ | |
1163 | part_right = pc_left - 1; | |
1164 | } | |
1165 | } else if (pc_right < part_right) { | |
1166 | /* There is only one chunk on the right to be sorted, make it | |
1167 | the new partition and loop back around. | |
1168 | */ | |
1169 | part_left = pc_right + 1; | |
1170 | } else { | |
1171 | /* This whole partition wound up in the pivot chunk, so | |
1172 | we need to get a new partition off the stack. | |
1173 | */ | |
1174 | if (next_stack_entry == 0) { | |
1175 | /* the stack is empty - we are done */ | |
1176 | break; | |
1177 | } | |
1178 | --next_stack_entry; | |
1179 | part_left = partition_stack[next_stack_entry].left; | |
1180 | part_right = partition_stack[next_stack_entry].right; | |
1181 | #ifdef QSORT_ORDER_GUESS | |
1182 | qsort_break_even = partition_stack[next_stack_entry].qsort_break_even; | |
1183 | #endif | |
1184 | } | |
1185 | } else { | |
1186 | /* This partition is too small to fool with qsort complexity, just | |
1187 | do an ordinary insertion sort to minimize overhead. | |
1188 | */ | |
1189 | int i; | |
1190 | /* Assume 1st element is in right place already, and start checking | |
1191 | at 2nd element to see where it should be inserted. | |
1192 | */ | |
1193 | for (i = part_left + 1; i <= part_right; ++i) { | |
1194 | int j; | |
1195 | /* Scan (backwards - just in case 'i' is already in right place) | |
1196 | through the elements already sorted to see if the ith element | |
1197 | belongs ahead of one of them. | |
1198 | */ | |
1199 | for (j = i - 1; j >= part_left; --j) { | |
1200 | if (qsort_cmp(i, j) >= 0) { | |
1201 | /* i belongs right after j | |
1202 | */ | |
1203 | break; | |
1204 | } | |
1205 | } | |
1206 | ++j; | |
1207 | if (j != i) { | |
1208 | /* Looks like we really need to move some things | |
1209 | */ | |
1210 | int k; | |
1211 | temp = array[i]; | |
1212 | for (k = i - 1; k >= j; --k) | |
1213 | array[k + 1] = array[k]; | |
1214 | array[j] = temp; | |
1215 | } | |
1216 | } | |
1217 | ||
1218 | /* That partition is now sorted, grab the next one, or get out | |
1219 | of the loop if there aren't any more. | |
1220 | */ | |
1221 | ||
1222 | if (next_stack_entry == 0) { | |
1223 | /* the stack is empty - we are done */ | |
1224 | break; | |
1225 | } | |
1226 | --next_stack_entry; | |
1227 | part_left = partition_stack[next_stack_entry].left; | |
1228 | part_right = partition_stack[next_stack_entry].right; | |
1229 | #ifdef QSORT_ORDER_GUESS | |
1230 | qsort_break_even = partition_stack[next_stack_entry].qsort_break_even; | |
1231 | #endif | |
1232 | } | |
1233 | } | |
1234 | ||
1235 | /* Believe it or not, the array is sorted at this point! */ | |
1236 | } | |
1237 | ||
84d4ea48 JH |
1238 | /* Stabilize what is, presumably, an otherwise unstable sort method. |
1239 | * We do that by allocating (or having on hand) an array of pointers | |
1240 | * that is the same size as the original array of elements to be sorted. | |
1241 | * We initialize this parallel array with the addresses of the original | |
1242 | * array elements. This indirection can make you crazy. | |
1243 | * Some pictures can help. After initializing, we have | |
1244 | * | |
1245 | * indir list1 | |
1246 | * +----+ +----+ | |
1247 | * | | --------------> | | ------> first element to be sorted | |
1248 | * +----+ +----+ | |
1249 | * | | --------------> | | ------> second element to be sorted | |
1250 | * +----+ +----+ | |
1251 | * | | --------------> | | ------> third element to be sorted | |
1252 | * +----+ +----+ | |
1253 | * ... | |
1254 | * +----+ +----+ | |
1255 | * | | --------------> | | ------> n-1st element to be sorted | |
1256 | * +----+ +----+ | |
1257 | * | | --------------> | | ------> n-th element to be sorted | |
1258 | * +----+ +----+ | |
1259 | * | |
1260 | * During the sort phase, we leave the elements of list1 where they are, | |
1261 | * and sort the pointers in the indirect array in the same order determined | |
1262 | * by the original comparison routine on the elements pointed to. | |
1263 | * Because we don't move the elements of list1 around through | |
1264 | * this phase, we can break ties on elements that compare equal | |
1265 | * using their address in the list1 array, ensuring stabilty. | |
1266 | * This leaves us with something looking like | |
1267 | * | |
1268 | * indir list1 | |
1269 | * +----+ +----+ | |
1270 | * | | --+ +---> | | ------> first element to be sorted | |
1271 | * +----+ | | +----+ | |
1272 | * | | --|-------|---> | | ------> second element to be sorted | |
1273 | * +----+ | | +----+ | |
1274 | * | | --|-------+ +-> | | ------> third element to be sorted | |
1275 | * +----+ | | +----+ | |
1276 | * ... | |
1277 | * +----+ | | | | +----+ | |
1278 | * | | ---|-+ | +--> | | ------> n-1st element to be sorted | |
1279 | * +----+ | | +----+ | |
1280 | * | | ---+ +----> | | ------> n-th element to be sorted | |
1281 | * +----+ +----+ | |
1282 | * | |
1283 | * where the i-th element of the indirect array points to the element | |
1284 | * that should be i-th in the sorted array. After the sort phase, | |
1285 | * we have to put the elements of list1 into the places | |
1286 | * dictated by the indirect array. | |
1287 | */ | |
1288 | ||
84d4ea48 JH |
1289 | |
1290 | static I32 | |
1291 | cmpindir(pTHX_ gptr a, gptr b) | |
1292 | { | |
1293 | I32 sense; | |
1294 | gptr *ap = (gptr *)a; | |
1295 | gptr *bp = (gptr *)b; | |
1296 | ||
147f47de | 1297 | if ((sense = PL_sort_RealCmp(aTHX_ *ap, *bp)) == 0) |
84d4ea48 JH |
1298 | sense = (ap > bp) ? 1 : ((ap < bp) ? -1 : 0); |
1299 | return sense; | |
1300 | } | |
1301 | ||
1302 | STATIC void | |
1303 | S_qsortsv(pTHX_ gptr *list1, size_t nmemb, SVCOMPARE_t cmp) | |
1304 | { | |
045ac317 | 1305 | SV *hintsv; |
84d4ea48 | 1306 | |
045ac317 | 1307 | if (SORTHINTS(hintsv) & HINT_SORT_STABLE) { |
84d4ea48 JH |
1308 | register gptr **pp, *q; |
1309 | register size_t n, j, i; | |
1310 | gptr *small[SMALLSORT], **indir, tmp; | |
1311 | SVCOMPARE_t savecmp; | |
1312 | if (nmemb <= 1) return; /* sorted trivially */ | |
4eb872f6 | 1313 | |
84d4ea48 JH |
1314 | /* Small arrays can use the stack, big ones must be allocated */ |
1315 | if (nmemb <= SMALLSORT) indir = small; | |
1316 | else { New(1799, indir, nmemb, gptr *); } | |
4eb872f6 | 1317 | |
84d4ea48 JH |
1318 | /* Copy pointers to original array elements into indirect array */ |
1319 | for (n = nmemb, pp = indir, q = list1; n--; ) *pp++ = q++; | |
4eb872f6 | 1320 | |
147f47de AB |
1321 | savecmp = PL_sort_RealCmp; /* Save current comparison routine, if any */ |
1322 | PL_sort_RealCmp = cmp; /* Put comparison routine where cmpindir can find it */ | |
4eb872f6 | 1323 | |
84d4ea48 JH |
1324 | /* sort, with indirection */ |
1325 | S_qsortsvu(aTHX_ (gptr *)indir, nmemb, cmpindir); | |
4eb872f6 | 1326 | |
84d4ea48 JH |
1327 | pp = indir; |
1328 | q = list1; | |
1329 | for (n = nmemb; n--; ) { | |
1330 | /* Assert A: all elements of q with index > n are already | |
1331 | * in place. This is vacuosly true at the start, and we | |
1332 | * put element n where it belongs below (if it wasn't | |
1333 | * already where it belonged). Assert B: we only move | |
1334 | * elements that aren't where they belong, | |
1335 | * so, by A, we never tamper with elements above n. | |
1336 | */ | |
1337 | j = pp[n] - q; /* This sets j so that q[j] is | |
1338 | * at pp[n]. *pp[j] belongs in | |
1339 | * q[j], by construction. | |
1340 | */ | |
1341 | if (n != j) { /* all's well if n == j */ | |
1342 | tmp = q[j]; /* save what's in q[j] */ | |
1343 | do { | |
1344 | q[j] = *pp[j]; /* put *pp[j] where it belongs */ | |
1345 | i = pp[j] - q; /* the index in q of the element | |
1346 | * just moved */ | |
1347 | pp[j] = q + j; /* this is ok now */ | |
1348 | } while ((j = i) != n); | |
1349 | /* There are only finitely many (nmemb) addresses | |
1350 | * in the pp array. | |
1351 | * So we must eventually revisit an index we saw before. | |
1352 | * Suppose the first revisited index is k != n. | |
1353 | * An index is visited because something else belongs there. | |
1354 | * If we visit k twice, then two different elements must | |
1355 | * belong in the same place, which cannot be. | |
1356 | * So j must get back to n, the loop terminates, | |
1357 | * and we put the saved element where it belongs. | |
1358 | */ | |
1359 | q[n] = tmp; /* put what belongs into | |
1360 | * the n-th element */ | |
1361 | } | |
1362 | } | |
1363 | ||
1364 | /* free iff allocated */ | |
1365 | if (indir != small) { Safefree(indir); } | |
1366 | /* restore prevailing comparison routine */ | |
147f47de | 1367 | PL_sort_RealCmp = savecmp; |
c53fc8a6 JH |
1368 | } else { |
1369 | S_qsortsvu(aTHX_ list1, nmemb, cmp); | |
84d4ea48 JH |
1370 | } |
1371 | } | |
4eb872f6 JL |
1372 | |
1373 | /* | |
ccfc67b7 JH |
1374 | =head1 Array Manipulation Functions |
1375 | ||
84d4ea48 JH |
1376 | =for apidoc sortsv |
1377 | ||
1378 | Sort an array. Here is an example: | |
1379 | ||
4eb872f6 | 1380 | sortsv(AvARRAY(av), av_len(av)+1, Perl_sv_cmp_locale); |
84d4ea48 | 1381 | |
78210658 AD |
1382 | See lib/sort.pm for details about controlling the sorting algorithm. |
1383 | ||
84d4ea48 JH |
1384 | =cut |
1385 | */ | |
4eb872f6 | 1386 | |
84d4ea48 JH |
1387 | void |
1388 | Perl_sortsv(pTHX_ SV **array, size_t nmemb, SVCOMPARE_t cmp) | |
1389 | { | |
1390 | void (*sortsvp)(pTHX_ SV **array, size_t nmemb, SVCOMPARE_t cmp) = | |
1391 | S_mergesortsv; | |
045ac317 | 1392 | SV *hintsv; |
84d4ea48 | 1393 | I32 hints; |
4eb872f6 | 1394 | |
78210658 AD |
1395 | /* Sun's Compiler (cc: WorkShop Compilers 4.2 30 Oct 1996 C 4.2) used |
1396 | to miscompile this function under optimization -O. If you get test | |
1397 | errors related to picking the correct sort() function, try recompiling | |
1398 | this file without optimiziation. -- A.D. 4/2002. | |
1399 | */ | |
045ac317 | 1400 | hints = SORTHINTS(hintsv); |
78210658 AD |
1401 | if (hints & HINT_SORT_QUICKSORT) { |
1402 | sortsvp = S_qsortsv; | |
1403 | } | |
1404 | else { | |
1405 | /* The default as of 5.8.0 is mergesort */ | |
1406 | sortsvp = S_mergesortsv; | |
84d4ea48 | 1407 | } |
4eb872f6 | 1408 | |
84d4ea48 JH |
1409 | sortsvp(aTHX_ array, nmemb, cmp); |
1410 | } | |
1411 | ||
1412 | PP(pp_sort) | |
1413 | { | |
1414 | dSP; dMARK; dORIGMARK; | |
1415 | register SV **up; | |
1416 | SV **myorigmark = ORIGMARK; | |
1417 | register I32 max; | |
1418 | HV *stash; | |
1419 | GV *gv; | |
1420 | CV *cv = 0; | |
1421 | I32 gimme = GIMME; | |
1422 | OP* nextop = PL_op->op_next; | |
1423 | I32 overloading = 0; | |
1424 | bool hasargs = FALSE; | |
1425 | I32 is_xsub = 0; | |
1426 | ||
1427 | if (gimme != G_ARRAY) { | |
1428 | SP = MARK; | |
1429 | RETPUSHUNDEF; | |
1430 | } | |
1431 | ||
1432 | ENTER; | |
1433 | SAVEVPTR(PL_sortcop); | |
1434 | if (PL_op->op_flags & OPf_STACKED) { | |
1435 | if (PL_op->op_flags & OPf_SPECIAL) { | |
1436 | OP *kid = cLISTOP->op_first->op_sibling; /* pass pushmark */ | |
1437 | kid = kUNOP->op_first; /* pass rv2gv */ | |
1438 | kid = kUNOP->op_first; /* pass leave */ | |
1439 | PL_sortcop = kid->op_next; | |
1440 | stash = CopSTASH(PL_curcop); | |
1441 | } | |
1442 | else { | |
1443 | cv = sv_2cv(*++MARK, &stash, &gv, 0); | |
1444 | if (cv && SvPOK(cv)) { | |
1445 | STRLEN n_a; | |
1446 | char *proto = SvPV((SV*)cv, n_a); | |
1447 | if (proto && strEQ(proto, "$$")) { | |
1448 | hasargs = TRUE; | |
1449 | } | |
1450 | } | |
1451 | if (!(cv && CvROOT(cv))) { | |
1452 | if (cv && CvXSUB(cv)) { | |
1453 | is_xsub = 1; | |
1454 | } | |
1455 | else if (gv) { | |
1456 | SV *tmpstr = sv_newmortal(); | |
1457 | gv_efullname3(tmpstr, gv, Nullch); | |
1458 | DIE(aTHX_ "Undefined sort subroutine \"%s\" called", | |
1459 | SvPVX(tmpstr)); | |
1460 | } | |
1461 | else { | |
1462 | DIE(aTHX_ "Undefined subroutine in sort"); | |
1463 | } | |
1464 | } | |
1465 | ||
1466 | if (is_xsub) | |
1467 | PL_sortcop = (OP*)cv; | |
1468 | else { | |
1469 | PL_sortcop = CvSTART(cv); | |
1470 | SAVEVPTR(CvROOT(cv)->op_ppaddr); | |
1471 | CvROOT(cv)->op_ppaddr = PL_ppaddr[OP_NULL]; | |
1472 | ||
1473 | SAVEVPTR(PL_curpad); | |
1474 | PL_curpad = AvARRAY((AV*)AvARRAY(CvPADLIST(cv))[1]); | |
1475 | } | |
1476 | } | |
1477 | } | |
1478 | else { | |
1479 | PL_sortcop = Nullop; | |
1480 | stash = CopSTASH(PL_curcop); | |
1481 | } | |
1482 | ||
1483 | up = myorigmark + 1; | |
1484 | while (MARK < SP) { /* This may or may not shift down one here. */ | |
1485 | /*SUPPRESS 560*/ | |
1486 | if ((*up = *++MARK)) { /* Weed out nulls. */ | |
1487 | SvTEMP_off(*up); | |
1488 | if (!PL_sortcop && !SvPOK(*up)) { | |
1489 | STRLEN n_a; | |
1490 | if (SvAMAGIC(*up)) | |
1491 | overloading = 1; | |
1492 | else | |
1493 | (void)sv_2pv(*up, &n_a); | |
1494 | } | |
1495 | up++; | |
1496 | } | |
1497 | } | |
1498 | max = --up - myorigmark; | |
1499 | if (PL_sortcop) { | |
1500 | if (max > 1) { | |
1501 | PERL_CONTEXT *cx; | |
1502 | SV** newsp; | |
1503 | bool oldcatch = CATCH_GET; | |
1504 | ||
1505 | SAVETMPS; | |
1506 | SAVEOP(); | |
1507 | ||
1508 | CATCH_SET(TRUE); | |
1509 | PUSHSTACKi(PERLSI_SORT); | |
1510 | if (!hasargs && !is_xsub) { | |
1511 | if (PL_sortstash != stash || !PL_firstgv || !PL_secondgv) { | |
1512 | SAVESPTR(PL_firstgv); | |
1513 | SAVESPTR(PL_secondgv); | |
1514 | PL_firstgv = gv_fetchpv("a", TRUE, SVt_PV); | |
1515 | PL_secondgv = gv_fetchpv("b", TRUE, SVt_PV); | |
1516 | PL_sortstash = stash; | |
1517 | } | |
1518 | #ifdef USE_5005THREADS | |
1519 | sv_lock((SV *)PL_firstgv); | |
1520 | sv_lock((SV *)PL_secondgv); | |
1521 | #endif | |
1522 | SAVESPTR(GvSV(PL_firstgv)); | |
1523 | SAVESPTR(GvSV(PL_secondgv)); | |
1524 | } | |
1525 | ||
1526 | PUSHBLOCK(cx, CXt_NULL, PL_stack_base); | |
1527 | if (!(PL_op->op_flags & OPf_SPECIAL)) { | |
1528 | cx->cx_type = CXt_SUB; | |
1529 | cx->blk_gimme = G_SCALAR; | |
1530 | PUSHSUB(cx); | |
1531 | if (!CvDEPTH(cv)) | |
1532 | (void)SvREFCNT_inc(cv); /* in preparation for POPSUB */ | |
1533 | } | |
1534 | PL_sortcxix = cxstack_ix; | |
1535 | ||
1536 | if (hasargs && !is_xsub) { | |
1537 | /* This is mostly copied from pp_entersub */ | |
1538 | AV *av = (AV*)PL_curpad[0]; | |
1539 | ||
1540 | #ifndef USE_5005THREADS | |
1541 | cx->blk_sub.savearray = GvAV(PL_defgv); | |
1542 | GvAV(PL_defgv) = (AV*)SvREFCNT_inc(av); | |
1543 | #endif /* USE_5005THREADS */ | |
1544 | cx->blk_sub.oldcurpad = PL_curpad; | |
1545 | cx->blk_sub.argarray = av; | |
1546 | } | |
1547 | sortsv((myorigmark+1), max, | |
1548 | is_xsub ? sortcv_xsub : hasargs ? sortcv_stacked : sortcv); | |
1549 | ||
1550 | POPBLOCK(cx,PL_curpm); | |
1551 | PL_stack_sp = newsp; | |
1552 | POPSTACK; | |
1553 | CATCH_SET(oldcatch); | |
1554 | } | |
1555 | } | |
1556 | else { | |
1557 | if (max > 1) { | |
1558 | MEXTEND(SP, 20); /* Can't afford stack realloc on signal. */ | |
1559 | sortsv(ORIGMARK+1, max, | |
1560 | (PL_op->op_private & OPpSORT_NUMERIC) | |
1561 | ? ( (PL_op->op_private & OPpSORT_INTEGER) | |
1562 | ? ( overloading ? amagic_i_ncmp : sv_i_ncmp) | |
1563 | : ( overloading ? amagic_ncmp : sv_ncmp)) | |
1564 | : ( IN_LOCALE_RUNTIME | |
1565 | ? ( overloading | |
1566 | ? amagic_cmp_locale | |
1567 | : sv_cmp_locale_static) | |
1568 | : ( overloading ? amagic_cmp : sv_cmp_static))); | |
1569 | if (PL_op->op_private & OPpSORT_REVERSE) { | |
1570 | SV **p = ORIGMARK+1; | |
1571 | SV **q = ORIGMARK+max; | |
1572 | while (p < q) { | |
1573 | SV *tmp = *p; | |
1574 | *p++ = *q; | |
1575 | *q-- = tmp; | |
1576 | } | |
1577 | } | |
1578 | } | |
1579 | } | |
1580 | LEAVE; | |
1581 | PL_stack_sp = ORIGMARK + max; | |
1582 | return nextop; | |
1583 | } | |
1584 | ||
1585 | static I32 | |
1586 | sortcv(pTHX_ SV *a, SV *b) | |
1587 | { | |
1588 | I32 oldsaveix = PL_savestack_ix; | |
1589 | I32 oldscopeix = PL_scopestack_ix; | |
1590 | I32 result; | |
1591 | GvSV(PL_firstgv) = a; | |
1592 | GvSV(PL_secondgv) = b; | |
1593 | PL_stack_sp = PL_stack_base; | |
1594 | PL_op = PL_sortcop; | |
1595 | CALLRUNOPS(aTHX); | |
1596 | if (PL_stack_sp != PL_stack_base + 1) | |
1597 | Perl_croak(aTHX_ "Sort subroutine didn't return single value"); | |
1598 | if (!SvNIOKp(*PL_stack_sp)) | |
1599 | Perl_croak(aTHX_ "Sort subroutine didn't return a numeric value"); | |
1600 | result = SvIV(*PL_stack_sp); | |
1601 | while (PL_scopestack_ix > oldscopeix) { | |
1602 | LEAVE; | |
1603 | } | |
1604 | leave_scope(oldsaveix); | |
1605 | return result; | |
1606 | } | |
1607 | ||
1608 | static I32 | |
1609 | sortcv_stacked(pTHX_ SV *a, SV *b) | |
1610 | { | |
1611 | I32 oldsaveix = PL_savestack_ix; | |
1612 | I32 oldscopeix = PL_scopestack_ix; | |
1613 | I32 result; | |
1614 | AV *av; | |
1615 | ||
1616 | #ifdef USE_5005THREADS | |
1617 | av = (AV*)PL_curpad[0]; | |
1618 | #else | |
1619 | av = GvAV(PL_defgv); | |
1620 | #endif | |
1621 | ||
1622 | if (AvMAX(av) < 1) { | |
1623 | SV** ary = AvALLOC(av); | |
1624 | if (AvARRAY(av) != ary) { | |
1625 | AvMAX(av) += AvARRAY(av) - AvALLOC(av); | |
1626 | SvPVX(av) = (char*)ary; | |
1627 | } | |
1628 | if (AvMAX(av) < 1) { | |
1629 | AvMAX(av) = 1; | |
1630 | Renew(ary,2,SV*); | |
1631 | SvPVX(av) = (char*)ary; | |
1632 | } | |
1633 | } | |
1634 | AvFILLp(av) = 1; | |
1635 | ||
1636 | AvARRAY(av)[0] = a; | |
1637 | AvARRAY(av)[1] = b; | |
1638 | PL_stack_sp = PL_stack_base; | |
1639 | PL_op = PL_sortcop; | |
1640 | CALLRUNOPS(aTHX); | |
1641 | if (PL_stack_sp != PL_stack_base + 1) | |
1642 | Perl_croak(aTHX_ "Sort subroutine didn't return single value"); | |
1643 | if (!SvNIOKp(*PL_stack_sp)) | |
1644 | Perl_croak(aTHX_ "Sort subroutine didn't return a numeric value"); | |
1645 | result = SvIV(*PL_stack_sp); | |
1646 | while (PL_scopestack_ix > oldscopeix) { | |
1647 | LEAVE; | |
1648 | } | |
1649 | leave_scope(oldsaveix); | |
1650 | return result; | |
1651 | } | |
1652 | ||
1653 | static I32 | |
1654 | sortcv_xsub(pTHX_ SV *a, SV *b) | |
1655 | { | |
1656 | dSP; | |
1657 | I32 oldsaveix = PL_savestack_ix; | |
1658 | I32 oldscopeix = PL_scopestack_ix; | |
1659 | I32 result; | |
1660 | CV *cv=(CV*)PL_sortcop; | |
1661 | ||
1662 | SP = PL_stack_base; | |
1663 | PUSHMARK(SP); | |
1664 | EXTEND(SP, 2); | |
1665 | *++SP = a; | |
1666 | *++SP = b; | |
1667 | PUTBACK; | |
1668 | (void)(*CvXSUB(cv))(aTHX_ cv); | |
1669 | if (PL_stack_sp != PL_stack_base + 1) | |
1670 | Perl_croak(aTHX_ "Sort subroutine didn't return single value"); | |
1671 | if (!SvNIOKp(*PL_stack_sp)) | |
1672 | Perl_croak(aTHX_ "Sort subroutine didn't return a numeric value"); | |
1673 | result = SvIV(*PL_stack_sp); | |
1674 | while (PL_scopestack_ix > oldscopeix) { | |
1675 | LEAVE; | |
1676 | } | |
1677 | leave_scope(oldsaveix); | |
1678 | return result; | |
1679 | } | |
1680 | ||
1681 | ||
1682 | static I32 | |
1683 | sv_ncmp(pTHX_ SV *a, SV *b) | |
1684 | { | |
1685 | NV nv1 = SvNV(a); | |
1686 | NV nv2 = SvNV(b); | |
1687 | return nv1 < nv2 ? -1 : nv1 > nv2 ? 1 : 0; | |
1688 | } | |
1689 | ||
1690 | static I32 | |
1691 | sv_i_ncmp(pTHX_ SV *a, SV *b) | |
1692 | { | |
1693 | IV iv1 = SvIV(a); | |
1694 | IV iv2 = SvIV(b); | |
1695 | return iv1 < iv2 ? -1 : iv1 > iv2 ? 1 : 0; | |
1696 | } | |
1697 | #define tryCALL_AMAGICbin(left,right,meth,svp) STMT_START { \ | |
1698 | *svp = Nullsv; \ | |
1699 | if (PL_amagic_generation) { \ | |
1700 | if (SvAMAGIC(left)||SvAMAGIC(right))\ | |
1701 | *svp = amagic_call(left, \ | |
1702 | right, \ | |
1703 | CAT2(meth,_amg), \ | |
1704 | 0); \ | |
1705 | } \ | |
1706 | } STMT_END | |
1707 | ||
1708 | static I32 | |
1709 | amagic_ncmp(pTHX_ register SV *a, register SV *b) | |
1710 | { | |
1711 | SV *tmpsv; | |
1712 | tryCALL_AMAGICbin(a,b,ncmp,&tmpsv); | |
1713 | if (tmpsv) { | |
1714 | NV d; | |
4eb872f6 | 1715 | |
84d4ea48 JH |
1716 | if (SvIOK(tmpsv)) { |
1717 | I32 i = SvIVX(tmpsv); | |
1718 | if (i > 0) | |
1719 | return 1; | |
1720 | return i? -1 : 0; | |
1721 | } | |
1722 | d = SvNV(tmpsv); | |
1723 | if (d > 0) | |
1724 | return 1; | |
1725 | return d? -1 : 0; | |
1726 | } | |
1727 | return sv_ncmp(aTHX_ a, b); | |
1728 | } | |
1729 | ||
1730 | static I32 | |
1731 | amagic_i_ncmp(pTHX_ register SV *a, register SV *b) | |
1732 | { | |
1733 | SV *tmpsv; | |
1734 | tryCALL_AMAGICbin(a,b,ncmp,&tmpsv); | |
1735 | if (tmpsv) { | |
1736 | NV d; | |
4eb872f6 | 1737 | |
84d4ea48 JH |
1738 | if (SvIOK(tmpsv)) { |
1739 | I32 i = SvIVX(tmpsv); | |
1740 | if (i > 0) | |
1741 | return 1; | |
1742 | return i? -1 : 0; | |
1743 | } | |
1744 | d = SvNV(tmpsv); | |
1745 | if (d > 0) | |
1746 | return 1; | |
1747 | return d? -1 : 0; | |
1748 | } | |
1749 | return sv_i_ncmp(aTHX_ a, b); | |
1750 | } | |
1751 | ||
1752 | static I32 | |
1753 | amagic_cmp(pTHX_ register SV *str1, register SV *str2) | |
1754 | { | |
1755 | SV *tmpsv; | |
1756 | tryCALL_AMAGICbin(str1,str2,scmp,&tmpsv); | |
1757 | if (tmpsv) { | |
1758 | NV d; | |
4eb872f6 | 1759 | |
84d4ea48 JH |
1760 | if (SvIOK(tmpsv)) { |
1761 | I32 i = SvIVX(tmpsv); | |
1762 | if (i > 0) | |
1763 | return 1; | |
1764 | return i? -1 : 0; | |
1765 | } | |
1766 | d = SvNV(tmpsv); | |
1767 | if (d > 0) | |
1768 | return 1; | |
1769 | return d? -1 : 0; | |
1770 | } | |
1771 | return sv_cmp(str1, str2); | |
1772 | } | |
1773 | ||
1774 | static I32 | |
1775 | amagic_cmp_locale(pTHX_ register SV *str1, register SV *str2) | |
1776 | { | |
1777 | SV *tmpsv; | |
1778 | tryCALL_AMAGICbin(str1,str2,scmp,&tmpsv); | |
1779 | if (tmpsv) { | |
1780 | NV d; | |
4eb872f6 | 1781 | |
84d4ea48 JH |
1782 | if (SvIOK(tmpsv)) { |
1783 | I32 i = SvIVX(tmpsv); | |
1784 | if (i > 0) | |
1785 | return 1; | |
1786 | return i? -1 : 0; | |
1787 | } | |
1788 | d = SvNV(tmpsv); | |
1789 | if (d > 0) | |
1790 | return 1; | |
1791 | return d? -1 : 0; | |
1792 | } | |
1793 | return sv_cmp_locale(str1, str2); | |
1794 | } |