caching for calcMRO
[gitmo/Class-C3-XS.git] / lib / Class / C3 / XS.xs
CommitLineData
8995e827 1
2#include "EXTERN.h"
3#include "perl.h"
4#include "XSUB.h"
8995e827 5
29e61e10 6/* Most of this code is backported from the bleadperl patch's
b23e9cb9 7 mro.c, and then modified to work with Class::C3's
8 internals.
9*/
8995e827 10
b23e9cb9 11AV*
12__mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level)
13{
14 AV* retval;
15 GV** gvp;
16 GV* gv;
17 AV* isa;
18 const char* stashname;
19 STRLEN stashname_len;
8995e827 20
b23e9cb9 21 assert(stash);
22 assert(HvAUX(stash));
8995e827 23
b23e9cb9 24 stashname = HvNAME(stash);
25 stashname_len = strlen(stashname);
26 if (!stashname)
27 Perl_croak(aTHX_
28 "Can't linearize anonymous symbol table");
8995e827 29
b23e9cb9 30 if (level > 100)
31 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
32 stashname);
8995e827 33
b23e9cb9 34 if(!cache) {
f0294f1b 35 cache = (HV*)sv_2mortal((SV*)newHV());
b23e9cb9 36 }
37 else {
f0294f1b 38 sv_dump(cache);
6bf46d18 39 SV** cache_entry = hv_fetch(cache, stashname, stashname_len, 0);
40 if(cache_entry)
41 return (AV*)SvREFCNT_inc(*cache_entry);
b23e9cb9 42 }
43
44 /* not in cache, make a new one */
45
46 retval = (AV*)sv_2mortal((SV*)newAV());
47 av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */
48
49 gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
50 isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL;
51
52 if(isa && AvFILLp(isa) >= 0) {
53 SV** seqs_ptr;
54 I32 seqs_items;
55 HV* tails = (HV*)sv_2mortal((SV*)newHV());
56 AV* seqs = (AV*)sv_2mortal((SV*)newAV());
57 I32 items = AvFILLp(isa) + 1;
58 SV** isa_ptr = AvARRAY(isa);
59 while(items--) {
60 AV* isa_lin;
61 SV* isa_item = *isa_ptr++;
62 HV* isa_item_stash = gv_stashsv(isa_item, 0);
63 if(!isa_item_stash) {
64 isa_lin = newAV();
65 av_push(isa_lin, newSVsv(isa_item));
66 }
67 else {
68 isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(isa_item_stash, cache, level + 1)); /* recursion */
69 }
70 av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin)));
71 }
72 av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa)));
73
74 seqs_ptr = AvARRAY(seqs);
75 seqs_items = AvFILLp(seqs) + 1;
76 while(seqs_items--) {
77 AV* seq = (AV*)*seqs_ptr++;
78 I32 seq_items = AvFILLp(seq);
79 if(seq_items > 0) {
80 SV** seq_ptr = AvARRAY(seq) + 1;
81 while(seq_items--) {
82 SV* seqitem = *seq_ptr++;
83 HE* he = hv_fetch_ent(tails, seqitem, 0, 0);
84 if(!he) {
85 hv_store_ent(tails, seqitem, newSViv(1), 0);
86 }
87 else {
88 SV* val = HeVAL(he);
89 sv_inc(val);
90 }
91 }
92 }
93 }
94
95 while(1) {
96 SV* seqhead = NULL;
97 SV* cand = NULL;
98 SV* winner = NULL;
99 SV* val;
100 HE* tail_entry;
101 AV* seq;
102 SV** avptr = AvARRAY(seqs);
103 items = AvFILLp(seqs)+1;
104 while(items--) {
105 SV** svp;
106 seq = (AV*)*avptr++;
107 if(AvFILLp(seq) < 0) continue;
108 svp = av_fetch(seq, 0, 0);
109 seqhead = *svp;
110 if(!winner) {
111 cand = seqhead;
112 if((tail_entry = hv_fetch_ent(tails, cand, 0, 0))
113 && (val = HeVAL(tail_entry))
114 && (SvIVx(val) > 0))
115 continue;
116 winner = newSVsv(cand);
117 av_push(retval, winner);
118 }
119 if(!sv_cmp(seqhead, winner)) {
120
121 /* this is basically shift(@seq) in void context */
122 SvREFCNT_dec(*AvARRAY(seq));
123 *AvARRAY(seq) = &PL_sv_undef;
124 AvARRAY(seq) = AvARRAY(seq) + 1;
125 AvMAX(seq)--;
126 AvFILLp(seq)--;
127
128 if(AvFILLp(seq) < 0) continue;
129 svp = av_fetch(seq, 0, 0);
130 seqhead = *svp;
131 tail_entry = hv_fetch_ent(tails, seqhead, 0, 0);
132 val = HeVAL(tail_entry);
133 sv_dec(val);
134 }
135 }
136 if(!cand) break;
137 if(!winner)
138 Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': "
139 "merging failed on parent '%s'", stashname, SvPV_nolen(cand));
140 }
141 }
142
143 SvREADONLY_on(retval);
144 SvREFCNT_inc(retval); /* for cache storage */
6bf46d18 145 SvREFCNT_inc(retval); /* for return */
f0294f1b 146 hv_store(cache, stashname, stashname_len, (SV*)retval, 0);
b23e9cb9 147 return retval;
148}
149
150STATIC I32
151__dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) {
152 I32 i;
153 for (i = startingblock; i >= 0; i--) {
154 if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i;
155 }
156 return i;
157}
158
159STATIC SV*
160__nextcan(pTHX_ SV* self, I32 throw_nomethod)
161{
162 register I32 cxix;
163 register const PERL_CONTEXT *ccstack = cxstack;
164 const PERL_SI *top_si = PL_curstackinfo;
165 HV* selfstash;
166 GV* cvgv;
167 SV *stashname;
168 const char *fq_subname;
169 const char *subname;
170 STRLEN fq_subname_len;
171 STRLEN stashname_len;
172 STRLEN subname_len;
173 SV* sv;
174 GV** gvp;
175 AV* linear_av;
176 SV** linear_svp;
177 SV* linear_sv;
178 HV* cstash;
179 GV* candidate = NULL;
180 CV* cand_cv = NULL;
181 const char *hvname;
182 I32 items;
183 struct mro_meta* selfmeta;
184 HV* nmcache;
185 HE* cache_entry;
186
187 if(sv_isobject(self))
188 selfstash = SvSTASH(SvRV(self));
189 else
190 selfstash = gv_stashsv(self, 0);
191
192 assert(selfstash);
193
194 hvname = HvNAME(selfstash);
195 if (!hvname)
196 croak("Can't use anonymous symbol table for method lookup");
197
198 cxix = __dopoptosub_at(cxstack, cxstack_ix);
199
200 /* This block finds the contextually-enclosing fully-qualified subname,
201 much like looking at (caller($i))[3] until you find a real sub that
202 isn't ANON, etc */
203 for (;;) {
204 /* we may be in a higher stacklevel, so dig down deeper */
205 while (cxix < 0) {
206 if(top_si->si_type == PERLSI_MAIN)
207 croak("next::method/next::can/maybe::next::method must be used in method context");
208 top_si = top_si->si_prev;
209 ccstack = top_si->si_cxstack;
210 cxix = __dopoptosub_at(ccstack, top_si->si_cxix);
211 }
212
213 if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB
214 || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) {
215 cxix = __dopoptosub_at(ccstack, cxix - 1);
216 continue;
217 }
218
219 {
220 const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1);
221 if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) {
222 if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) {
223 cxix = dbcxix;
224 continue;
225 }
226 }
227 }
228
229 cvgv = CvGV(ccstack[cxix].blk_sub.cv);
230
231 if(!isGV(cvgv)) {
232 cxix = __dopoptosub_at(ccstack, cxix - 1);
233 continue;
234 }
235
236 /* we found a real sub here */
237 sv = sv_2mortal(newSV(0));
238
239 gv_efullname3(sv, cvgv, NULL);
240
241 fq_subname = SvPVX(sv);
242 fq_subname_len = SvCUR(sv);
243
244 subname = strrchr(fq_subname, ':');
245 if(!subname)
246 croak("next::method/next::can/maybe::next::method cannot find enclosing method");
247
248 subname++;
249 subname_len = fq_subname_len - (subname - fq_subname);
250 if(subname_len == 8 && strEQ(subname, "__ANON__")) {
251 cxix = __dopoptosub_at(ccstack, cxix - 1);
252 continue;
253 }
254 break;
255 }
256
257 /* If we made it to here, we found our context */
258
259 /*
260 XXX check %next::METHOD_CACHE
261
262 selfmeta = HvMROMETA(selfstash);
263 if(!(nmcache = selfmeta->mro_nextmethod)) {
264 nmcache = selfmeta->mro_nextmethod = newHV();
265 }
266
267 if((cache_entry = hv_fetch_ent(nmcache, sv, 0, 0))) {
268 SV* val = HeVAL(cache_entry);
269 if(val == &PL_sv_undef) {
270 if(throw_nomethod)
271 croak("No next::method '%s' found for %s", subname, hvname);
272 return &PL_sv_undef;
273 }
274 return SvREFCNT_inc(val);
275 }
276 */
277
278 /* beyond here is just for cache misses, so perf isn't as critical */
279
280 stashname_len = subname - fq_subname - 2;
281 stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len));
282
6bf46d18 283 linear_av = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(selfstash, NULL, 0));
b23e9cb9 284
285 linear_svp = AvARRAY(linear_av);
286 items = AvFILLp(linear_av) + 1;
287
288 while (items--) {
289 linear_sv = *linear_svp++;
290 assert(linear_sv);
291 if(sv_eq(linear_sv, stashname))
292 break;
293 }
294
295 if(items > 0) {
29e61e10 296 SV* sub_sv = sv_2mortal(newSVpv(subname, subname_len));
297 HV* cc3_mro = get_hv("Class::C3::MRO", 0);
29e61e10 298
b23e9cb9 299 while (items--) {
300 linear_sv = *linear_svp++;
301 assert(linear_sv);
29e61e10 302
303 if(cc3_mro) {
304 HE* he_cc3_mro_class = hv_fetch_ent(cc3_mro, linear_sv, 0, 0);
305 if(he_cc3_mro_class) {
efafd620 306 HV* cc3_mro_class = (HV*)SvRV(HeVAL(he_cc3_mro_class));
307 SV** svp_cc3_mro_class_methods = hv_fetch(cc3_mro_class, "methods", 7, 0);
308 if(svp_cc3_mro_class_methods) {
309 HV* cc3_mro_class_methods = (HV*)SvRV(*svp_cc3_mro_class_methods);
29e61e10 310 if(hv_exists_ent(cc3_mro_class_methods, sub_sv, 0))
311 continue;
312 }
313 }
314 }
315
b23e9cb9 316 cstash = gv_stashsv(linear_sv, FALSE);
317
318 if (!cstash) {
319 if (ckWARN(WARN_MISC))
320 Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
321 (void*)linear_sv, hvname);
322 continue;
323 }
324
325 assert(cstash);
326
b23e9cb9 327 gvp = (GV**)hv_fetch(cstash, subname, subname_len, 0);
328 if (!gvp) continue;
329
330 candidate = *gvp;
331 assert(candidate);
332
333 if (SvTYPE(candidate) != SVt_PVGV)
334 gv_init(candidate, cstash, subname, subname_len, TRUE);
335 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
336 SvREFCNT_inc((SV*)cand_cv);
337 /* XXX store result in cache */
338 /* hv_store_ent(nmcache, newSVsv(sv), (SV*)cand_cv, 0); */
339 return (SV*)cand_cv;
340 }
341 }
342 }
343
344 /* XXX store undef in cache */
345 /* hv_store_ent(nmcache, newSVsv(sv), &PL_sv_undef, 0); */
346 if(throw_nomethod)
347 croak("No next::method '%s' found for %s", subname, hvname);
348 return &PL_sv_undef;
349}
350
351XS(XS_Class_C3_XS_calculateMRO);
352XS(XS_Class_C3_XS_calculateMRO)
353{
354#ifdef dVAR
355 dVAR; dXSARGS;
356#else
357 dXSARGS;
358#endif
359
360 SV* classname;
361 HV* class_stash;
362 HV* cache = NULL;
363 AV* res;
364 I32 res_items;
365 I32 ret_items;
366 SV** res_ptr;
367
368 if(items < 1 || items > 2)
369 croak("Usage: calculateMRO(classname[, cache])");
370
371 classname = ST(0);
f0294f1b 372 if(items == 2) cache = (HV*)SvRV(ST(1));
b23e9cb9 373
374 class_stash = gv_stashsv(classname, 0);
375 if(!class_stash) croak("No such class: '%s'!", SvPV_nolen(classname));
376
377 res = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(class_stash, cache, 0));
378
b23e9cb9 379 res_items = ret_items = AvFILLp(res) + 1;
380 res_ptr = AvARRAY(res);
381
382 SP -= items;
383
384 while(res_items--) {
385 SV* res_item = *res_ptr++;
386 XPUSHs(res_item);
387 }
388
389 PUTBACK;
390
391 return;
392}
393
394XS(XS_next_can);
395XS(XS_next_can)
396{
397#ifdef dVAR
398 dVAR; dXSARGS;
399#else
400 dXSARGS;
401#endif
402
403 SV* self = ST(0);
404 SV* methcv = __nextcan(self, 0);
405
406 PERL_UNUSED_VAR(items);
407
408 if(methcv == &PL_sv_undef) {
409 ST(0) = &PL_sv_undef;
410 }
411 else {
412 ST(0) = sv_2mortal(newRV_inc(methcv));
413 }
414
415 XSRETURN(1);
416}
417
418XS(XS_next_method);
419XS(XS_next_method)
420{
421 dMARK;
422 dAX;
423 SV* self = ST(0);
424 SV* methcv = __nextcan(self, 1);
425
426 PL_markstack_ptr++;
427 call_sv(methcv, GIMME_V);
428}
429
430XS(XS_maybe_next_method);
431XS(XS_maybe_next_method)
432{
433 dMARK;
434 dAX;
435 SV* self = ST(0);
436 SV* methcv = __nextcan(self, 0);
437
438 if(methcv == &PL_sv_undef) {
439 ST(0) = &PL_sv_undef;
440 XSRETURN(1);
441 }
442
443 PL_markstack_ptr++;
444 call_sv(methcv, GIMME_V);
445}
446
447MODULE = Class::C3::XS PACKAGE = Class::C3::XS
448
449BOOT:
450 newXS("Class::C3::XS::calculateMRO", XS_Class_C3_XS_calculateMRO, __FILE__);
451 newXS("next::can", XS_next_can, __FILE__);
452 newXS("next::method", XS_next_method, __FILE__);
453 newXS("maybe::next::method", XS_maybe_next_method, __FILE__);