X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/a083fbbf221545ea6e68a831da060d8834f36eca..9b33de72cd2469bedac2b5f0a48a8782571ea9db:/src/derives.c diff --git a/src/derives.c b/src/derives.c index 33a8a035..2e4ff31b 100644 --- a/src/derives.c +++ b/src/derives.c @@ -1,118 +1,121 @@ /* Match rules with nonterminals for bison, - Copyright (C) 1984, 1989 Free Software Foundation, Inc. -This file is part of Bison, the GNU Compiler Compiler. + Copyright (C) 1984, 1989, 2000, 2001, 2002, 2003, 2005 Free + Software Foundation, Inc. -Bison is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. + This file is part of Bison, the GNU Compiler Compiler. -Bison is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. + Bison is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. -You should have received a copy of the GNU General Public License -along with Bison; see the file COPYING. If not, write to -the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + Bison is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + You should have received a copy of the GNU General Public License + along with Bison; see the file COPYING. If not, write to + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. */ -/* set_derives finds, for each variable (nonterminal), which rules can derive it. - It sets up the value of derives so that - derives[i - ntokens] points to a vector of rule numbers, - terminated with -1. */ - -#include +#include #include "system.h" -#include "new.h" -#include "types.h" + +#include "getargs.h" + +#include "derives.h" #include "gram.h" +#include "reader.h" +#include "symtab.h" +/* Linked list of rule numbers. */ +typedef struct rule_list +{ + struct rule_list *next; + rule *value; +} rule_list; -short **derives; +rule ***derives; -void -set_derives() +static void +print_derives (void) { - register int i; - register int lhs; - register shorts *p; - register short *q; - register shorts **dset; - register shorts *delts; - - dset = NEW2(nvars, shorts *) - ntokens; - delts = NEW2(nrules + 1, shorts); - - p = delts; - for (i = nrules; i > 0; i--) - { - lhs = rlhs[i]; - if (lhs >= 0) - { - p->next = dset[lhs]; - p->value = i; - dset[lhs] = p; - p++; - } - } + int i; - derives = NEW2(nvars, short *) - ntokens; - q = NEW2(nvars + nrules, short); + fputs ("DERIVES\n", stderr); for (i = ntokens; i < nsyms; i++) { - derives[i] = q; - p = dset[i]; - while (p) + rule **rp; + fprintf (stderr, "\t%s derives\n", symbols[i]->tag); + for (rp = derives[i - ntokens]; *rp; ++rp) { - *q++ = p->value; - p = p->next; + fprintf (stderr, "\t\t%3d ", (*rp)->user_number); + rule_rhs_print (*rp, stderr); } - *q++ = -1; } -#ifdef DEBUG - print_derives(); -#endif - - FREE(dset + ntokens); - FREE(delts); + fputs ("\n\n", stderr); } + void -free_derives() +derives_compute (void) { - FREE(derives[ntokens]); - FREE(derives + ntokens); -} + symbol_number i; + rule_number r; + rule **q; + /* DSET[NTERM - NTOKENS] -- A linked list of the numbers of the rules + whose LHS is NTERM. */ + rule_list **dset = xcalloc (nvars, sizeof *dset); + /* DELTS[RULE] -- There are NRULES rule number to attach to nterms. + Instead of performing NRULES allocations for each, have an array + indexed by rule numbers. */ + rule_list *delts = xnmalloc (nrules, sizeof *delts); -#ifdef DEBUG - -print_derives() -{ - register int i; - register short *sp; + for (r = nrules - 1; r >= 0; --r) + { + symbol_number lhs = rules[r].lhs->number; + rule_list *p = &delts[r]; + /* A new LHS is found. */ + p->next = dset[lhs - ntokens]; + p->value = &rules[r]; + dset[lhs - ntokens] = p; + } - extern char **tags; + /* DSET contains what we need under the form of a linked list. Make + it a single array. */ - printf(_("\n\n\nDERIVES\n\n")); + derives = xnmalloc (nvars, sizeof *derives); + q = xnmalloc (nvars + nrules, sizeof *q); for (i = ntokens; i < nsyms; i++) { - printf(_("%s derives"), tags[i]); - for (sp = derives[i]; *sp > 0; sp++) + rule_list *p = dset[i - ntokens]; + derives[i - ntokens] = q; + while (p) { - printf(" %d", *sp); + *q++ = p->value; + p = p->next; } - putchar('\n'); + *q++ = NULL; } - putchar('\n'); + if (trace_flag & trace_sets) + print_derives (); + + free (dset); + free (delts); } -#endif +void +derives_free (void) +{ + free (derives[0]); + free (derives); +}