From: Brandon L Black Date: Mon, 14 May 2007 16:11:28 +0000 (+0000) Subject: some backporting of 5.9.5 mro.c changes, + memory management fixups X-Git-Tag: 0.05~2 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=gitmo%2FClass-C3-XS.git;a=commitdiff_plain;h=bb82f0c1222ed18914a366bf6de5a25564dff0b1 some backporting of 5.9.5 mro.c changes, + memory management fixups --- diff --git a/XS.xs b/XS.xs index cf6880a..20c1ea6 100644 --- a/XS.xs +++ b/XS.xs @@ -17,8 +17,10 @@ __mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level) AV* isa; const char* stashname; STRLEN stashname_len; + I32 made_mortal_cache = 0; assert(stash); + assert(HvAUX(stash)); stashname = HvNAME(stash); stashname_len = strlen(stashname); @@ -32,6 +34,7 @@ __mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level) if(!cache) { cache = (HV*)sv_2mortal((SV*)newHV()); + made_mortal_cache = 1; } else { SV** cache_entry = hv_fetch(cache, stashname, stashname_len, 0); @@ -41,71 +44,85 @@ __mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level) /* not in cache, make a new one */ - retval = newAV(); - av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */ - gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE); isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL; if(isa && AvFILLp(isa) >= 0) { SV** seqs_ptr; I32 seqs_items; - HV* tails = (HV*)sv_2mortal((SV*)newHV()); - AV* seqs = (AV*)sv_2mortal((SV*)newAV()); + HV* const tails = (HV*)sv_2mortal((SV*)newHV()); + AV* const seqs = (AV*)sv_2mortal((SV*)newAV()); + I32* heads; + I32 items = AvFILLp(isa) + 1; SV** isa_ptr = AvARRAY(isa); while(items--) { - AV* isa_lin; - SV* isa_item = *isa_ptr++; - HV* isa_item_stash = gv_stashsv(isa_item, 0); + SV* const isa_item = *isa_ptr++; + HV* const isa_item_stash = gv_stashsv(isa_item, 0); if(!isa_item_stash) { - isa_lin = newAV(); + AV* const isa_lin = newAV(); av_push(isa_lin, newSVsv(isa_item)); + av_push(seqs, (SV*)isa_lin); } else { - isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ isa_item_stash, cache, level + 1)); /* recursion */ + AV* const isa_lin = __mro_linear_isa_c3(aTHX_ isa_item_stash, cache, level + 1); /* recursion */ + av_push(seqs, (SV*)isa_lin); } - av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin))); } - av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa))); + av_push(seqs, SvREFCNT_inc((SV*)isa)); + + /* This builds "heads", which as an array of integer array + indices, one per seq, which point at the virtual "head" + of the seq (initially zero) */ + + Newz(0xdead, heads, AvFILLp(seqs)+1, I32); + /* This builds %tails, which has one key for every class + mentioned in the tail of any sequence in @seqs (tail meaning + everything after the first class, the "head"). The value + is how many times this key appears in the tails of @seqs. + */ seqs_ptr = AvARRAY(seqs); seqs_items = AvFILLp(seqs) + 1; while(seqs_items--) { - AV* seq = (AV*)*seqs_ptr++; + AV* const seq = (AV*)*seqs_ptr++; I32 seq_items = AvFILLp(seq); if(seq_items > 0) { SV** seq_ptr = AvARRAY(seq) + 1; while(seq_items--) { - SV* seqitem = *seq_ptr++; - HE* he = hv_fetch_ent(tails, seqitem, 0, 0); + SV* const seqitem = *seq_ptr++; + HE* const he = hv_fetch_ent(tails, seqitem, 0, 0); if(!he) { hv_store_ent(tails, seqitem, newSViv(1), 0); } else { - SV* val = HeVAL(he); + SV* const val = HeVAL(he); sv_inc(val); } } } } + /* Initialize retval to build the return value in */ + retval = newAV(); + av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */ + while(1) { - SV* seqhead = NULL; SV* cand = NULL; SV* winner = NULL; - SV* val; - HE* tail_entry; - AV* seq; - SV** avptr = AvARRAY(seqs); - items = AvFILLp(seqs)+1; - while(items--) { + int s; + + SV** const avptr = AvARRAY(seqs); + for(s = 0; s <= AvFILLp(seqs); s++) { SV** svp; - seq = (AV*)*avptr++; - if(AvFILLp(seq) < 0) continue; - svp = av_fetch(seq, 0, 0); + AV * const seq = (AV*)(avptr[s]); + SV* seqhead; + if(!seq) continue; + svp = av_fetch(seq, heads[s], 0); seqhead = *svp; if(!winner) { + HE* tail_entry; + SV* val; cand = seqhead; if((tail_entry = hv_fetch_ent(tails, cand, 0, 0)) && (val = HeVAL(tail_entry)) @@ -115,27 +132,50 @@ __mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level) av_push(retval, winner); } if(!sv_cmp(seqhead, winner)) { - sv_2mortal(av_shift(seq)); - if(AvFILLp(seq) < 0) continue; - svp = av_fetch(seq, 0, 0); - seqhead = *svp; - tail_entry = hv_fetch_ent(tails, seqhead, 0, 0); - val = HeVAL(tail_entry); - sv_dec(val); + const int new_head = ++heads[s]; + if(new_head > AvFILLp(seq)) { + SvREFCNT_dec(avptr[s]); + avptr[s] = NULL; + } + else { + HE* tail_entry; + SV* val; + /* Because we know this new seqhead used to be + a tail, we can assume it is in tails and has + a positive value, which we need to dec */ + svp = av_fetch(seq, new_head, 0); + seqhead = *svp; + tail_entry = hv_fetch_ent(tails, seqhead, 0, 0); + val = HeVAL(tail_entry); + sv_dec(val); + } } } - if(!cand) break; + if(!cand) { + Safefree(heads); + break; + } if(!winner) { SvREFCNT_dec(retval); + Safefree(heads); Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': " "merging failed on parent '%s'", stashname, SvPV_nolen(cand)); } } } + else { /* @ISA does not exist, or was empty */ + retval = newAV(); + av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */ + } SvREADONLY_on(retval); - hv_store(cache, stashname, stashname_len, (SV*)retval, 0); - return (AV*)SvREFCNT_inc(retval); + + if(!made_mortal_cache) { + SvREFCNT_inc(retval); + hv_store(cache, stashname, stashname_len, (SV*)retval, 0); + } + + return retval; } STATIC I32 @@ -438,10 +478,9 @@ XS(XS_Class_C3_XS_calc_mdt) class_mro = __mro_linear_isa_c3(aTHX_ class_stash, cache, 0); our_c3mro = newHV(); - hv_store(our_c3mro, "MRO", 3, (SV*)newRV_inc((SV*)class_mro), 0); + hv_store(our_c3mro, "MRO", 3, (SV*)newRV_noinc((SV*)class_mro), 0); hv = get_hv("Class::C3::MRO", 1); - hv_delete_ent(hv, classname, G_DISCARD, 0); hv_store_ent(hv, classname, (SV*)newRV_noinc((SV*)our_c3mro), 0); methods = newHV();