+
+/* print the names of the n lexical vars starting at pad offset off */
+
+STATIC void
+S_deb_padvar(pTHX_ PADOFFSET off, int n, bool paren)
+{
+ PADNAME *sv;
+ CV * const cv = deb_curcv(cxstack_ix);
+ PADNAMELIST *comppad = NULL;
+ int i;
+
+ if (cv) {
+ PADLIST * const padlist = CvPADLIST(cv);
+ comppad = PadlistNAMES(padlist);
+ }
+ if (paren)
+ PerlIO_printf(Perl_debug_log, "(");
+ for (i = 0; i < n; i++) {
+ if (comppad && (sv = padnamelist_fetch(comppad, off + i)))
+ PerlIO_printf(Perl_debug_log, "%"PNf, PNfARG(sv));
+ else
+ PerlIO_printf(Perl_debug_log, "[%"UVuf"]",
+ (UV)(off+i));
+ if (i < n - 1)
+ PerlIO_printf(Perl_debug_log, ",");
+ }
+ if (paren)
+ PerlIO_printf(Perl_debug_log, ")");
+}
+
+
+/* append to the out SV, the name of the lexical at offset off in the CV
+ * cv */
+
+static void
+S_append_padvar(pTHX_ PADOFFSET off, CV *cv, SV *out, int n,
+ bool paren, bool is_scalar)
+{
+ PADNAME *sv;
+ PADNAMELIST *namepad = NULL;
+ int i;
+
+ if (cv) {
+ PADLIST * const padlist = CvPADLIST(cv);
+ namepad = PadlistNAMES(padlist);
+ }
+
+ if (paren)
+ sv_catpvs_nomg(out, "(");
+ for (i = 0; i < n; i++) {
+ if (namepad && (sv = padnamelist_fetch(namepad, off + i)))
+ {
+ STRLEN cur = SvCUR(out);
+ Perl_sv_catpvf(aTHX_ out, "[%"UTF8f,
+ UTF8fARG(1, PadnameLEN(sv) - 1,
+ PadnamePV(sv) + 1));
+ if (is_scalar)
+ SvPVX(out)[cur] = '$';
+ }
+ else
+ Perl_sv_catpvf(aTHX_ out, "[%"UVuf"]", (UV)(off+i));
+ if (i < n - 1)
+ sv_catpvs_nomg(out, ",");
+ }
+ if (paren)
+ sv_catpvs_nomg(out, "(");
+}
+
+
+static void
+S_append_gv_name(pTHX_ GV *gv, SV *out)
+{
+ SV *sv;
+ if (!gv) {
+ sv_catpvs_nomg(out, "<NULLGV>");
+ return;
+ }
+ sv = newSV(0);
+ gv_fullname4(sv, gv, NULL, FALSE);
+ Perl_sv_catpvf(aTHX_ out, "$%"SVf, SVfARG(sv));
+ SvREFCNT_dec_NN(sv);
+}
+
+#ifdef USE_ITHREADS
+# define ITEM_SV(item) (comppad ? \
+ *av_fetch(comppad, (item)->pad_offset, FALSE) : NULL);
+#else
+# define ITEM_SV(item) UNOP_AUX_item_sv(item)
+#endif
+
+
+/* return a temporary SV containing a stringified representation of
+ * the op_aux field of a MULTIDEREF op, associated with CV cv
+ */
+
+SV*
+Perl_multideref_stringify(pTHX_ const OP *o, CV *cv)
+{
+ UNOP_AUX_item *items = cUNOP_AUXo->op_aux;
+ UV actions = items->uv;
+ SV *sv;
+ bool last = 0;
+ bool is_hash = FALSE;
+ int derefs = 0;
+ SV *out = newSVpvn_flags("",0,SVs_TEMP);
+#ifdef USE_ITHREADS
+ PAD *comppad;
+
+ if (cv) {
+ PADLIST *padlist = CvPADLIST(cv);
+ comppad = PadlistARRAY(padlist)[1];
+ }
+ else
+ comppad = NULL;
+#endif
+
+ PERL_ARGS_ASSERT_MULTIDEREF_STRINGIFY;
+
+ while (!last) {
+ switch (actions & MDEREF_ACTION_MASK) {
+
+ case MDEREF_reload:
+ actions = (++items)->uv;
+ continue;
+ NOT_REACHED; /* NOTREACHED */
+
+ case MDEREF_HV_padhv_helem:
+ is_hash = TRUE;
+ /* FALLTHROUGH */
+ case MDEREF_AV_padav_aelem:
+ derefs = 1;
+ S_append_padvar(aTHX_ (++items)->pad_offset, cv, out, 1, 0, 1);
+ goto do_elem;
+ NOT_REACHED; /* NOTREACHED */
+
+ case MDEREF_HV_gvhv_helem:
+ is_hash = TRUE;
+ /* FALLTHROUGH */
+ case MDEREF_AV_gvav_aelem:
+ derefs = 1;
+ items++;
+ sv = ITEM_SV(items);
+ S_append_gv_name(aTHX_ (GV*)sv, out);
+ goto do_elem;
+ NOT_REACHED; /* NOTREACHED */
+
+ case MDEREF_HV_gvsv_vivify_rv2hv_helem:
+ is_hash = TRUE;
+ /* FALLTHROUGH */
+ case MDEREF_AV_gvsv_vivify_rv2av_aelem:
+ items++;
+ sv = ITEM_SV(items);
+ S_append_gv_name(aTHX_ (GV*)sv, out);
+ goto do_vivify_rv2xv_elem;
+ NOT_REACHED; /* NOTREACHED */
+
+ case MDEREF_HV_padsv_vivify_rv2hv_helem:
+ is_hash = TRUE;
+ /* FALLTHROUGH */
+ case MDEREF_AV_padsv_vivify_rv2av_aelem:
+ S_append_padvar(aTHX_ (++items)->pad_offset, cv, out, 1, 0, 1);
+ goto do_vivify_rv2xv_elem;
+ NOT_REACHED; /* NOTREACHED */
+
+ case MDEREF_HV_pop_rv2hv_helem:
+ case MDEREF_HV_vivify_rv2hv_helem:
+ is_hash = TRUE;
+ /* FALLTHROUGH */
+ do_vivify_rv2xv_elem:
+ case MDEREF_AV_pop_rv2av_aelem:
+ case MDEREF_AV_vivify_rv2av_aelem:
+ if (!derefs++)
+ sv_catpvs_nomg(out, "->");
+ do_elem:
+ if ((actions & MDEREF_INDEX_MASK)== MDEREF_INDEX_none) {
+ sv_catpvs_nomg(out, "->");
+ last = 1;
+ break;
+ }
+
+ sv_catpvn_nomg(out, (is_hash ? "{" : "["), 1);
+ switch (actions & MDEREF_INDEX_MASK) {
+ case MDEREF_INDEX_const:
+ if (is_hash) {
+ items++;
+ sv = ITEM_SV(items);
+ if (!sv)
+ sv_catpvs_nomg(out, "???");
+ else {
+ STRLEN cur;
+ char *s;
+ s = SvPV(sv, cur);
+ pv_pretty(out, s, cur, 30,
+ NULL, NULL,
+ (PERL_PV_PRETTY_NOCLEAR
+ |PERL_PV_PRETTY_QUOTE
+ |PERL_PV_PRETTY_ELLIPSES));
+ }
+ }
+ else
+ Perl_sv_catpvf(aTHX_ out, "%"IVdf, (++items)->iv);
+ break;
+ case MDEREF_INDEX_padsv:
+ S_append_padvar(aTHX_ (++items)->pad_offset, cv, out, 1, 0, 1);
+ break;
+ case MDEREF_INDEX_gvsv:
+ items++;
+ sv = ITEM_SV(items);
+ S_append_gv_name(aTHX_ (GV*)sv, out);
+ break;
+ }
+ sv_catpvn_nomg(out, (is_hash ? "}" : "]"), 1);
+
+ if (actions & MDEREF_FLAG_last)
+ last = 1;
+ is_hash = FALSE;
+
+ break;
+
+ default:
+ PerlIO_printf(Perl_debug_log, "UNKNOWN(%d)",
+ (int)(actions & MDEREF_ACTION_MASK));
+ last = 1;
+ break;
+
+ } /* switch */
+
+ actions >>= MDEREF_SHIFT;
+ } /* while */
+ return out;
+}
+
+