X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/17ee7397a87c4c4ccd45f956e0b88b824a3689f9..fcd32abd3a4b68ef525d7766dbed1c98465e23b9:/src/reduce.c?ds=inline diff --git a/src/reduce.c b/src/reduce.c index fa09b497..67e72a36 100644 --- a/src/reduce.c +++ b/src/reduce.c @@ -1,22 +1,22 @@ /* Grammar reduction for Bison. - Copyright (C) 1988, 1989, 2000, 2001, 2002 Free Software Foundation, Inc. + + Copyright (C) 1988, 1989, 2000, 2001, 2002, 2003, 2005, 2006, 2007, + 2008-2009 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. - Bison is free software; you can redistribute it and/or modify + This program 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. + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. - Bison is distributed in the hope that it will be useful, + This program 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., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. */ + along with this program. If not, see . */ /* Reduce the grammar: Find and eliminate unreachable terminals, @@ -25,6 +25,7 @@ /* Don't eliminate unreachable terminals: They may be used by the user's parser. */ +#include #include "system.h" #include @@ -34,6 +35,7 @@ #include "files.h" #include "getargs.h" #include "gram.h" +#include "print-xml.h" #include "reader.h" #include "reduce.h" #include "symtab.h" @@ -237,7 +239,7 @@ reduce_grammar_tables (void) rule_number r; for (r = 0; r < nrules; r++) rules[r].useful = bitset_test (P, r); - grammar_rules_never_reduced_report (_("useless rule")); + grammar_rules_useless_report (_("rule useless in grammar")); } /* Map the nonterminals to their new index: useful first, useless @@ -245,7 +247,7 @@ reduce_grammar_tables (void) { int useful = 0; int useless = nrules - nuseless_productions; - rule *rules_sorted = XMALLOC (rule, nrules); + rule *rules_sorted = xnmalloc (nrules, sizeof *rules_sorted); rule_number r; for (r = 0; r < nrules; ++r) rules_sorted[rules[r].useful ? useful++ : useless++] = rules[r]; @@ -266,7 +268,7 @@ reduce_grammar_tables (void) /* Adjust NRITEMS. */ { - int r; + rule_number r; int length; for (r = nrules; r < nrules + nuseless_productions; ++r) { @@ -289,31 +291,31 @@ nonterminals_reduce (void) /* Map the nonterminals to their new index: useful first, useless afterwards. Kept for later report. */ - symbol_number *nontermmap = XCALLOC (symbol_number, nvars) - ntokens; + symbol_number *nontermmap = xnmalloc (nvars, sizeof *nontermmap); n = ntokens; for (i = ntokens; i < nsyms; i++) if (bitset_test (V, i)) - nontermmap[i] = n++; + nontermmap[i - ntokens] = n++; for (i = ntokens; i < nsyms; i++) if (!bitset_test (V, i)) { - nontermmap[i] = n++; - warn_at (symbols[i]->location, _("useless nonterminal: %s"), + nontermmap[i - ntokens] = n++; + warn_at (symbols[i]->location, _("nonterminal useless in grammar: %s"), symbols[i]->tag); } /* Shuffle elements of tables indexed by symbol number. */ { - symbol **symbols_sorted = XMALLOC (symbol *, nvars) - ntokens; + symbol **symbols_sorted = xnmalloc (nvars, sizeof *symbols_sorted); for (i = ntokens; i < nsyms; i++) - symbols[i]->number = nontermmap[i]; + symbols[i]->number = nontermmap[i - ntokens]; for (i = ntokens; i < nsyms; i++) - symbols_sorted[nontermmap[i]] = symbols[i]; + symbols_sorted[nontermmap[i - ntokens] - ntokens] = symbols[i]; for (i = ntokens; i < nsyms; i++) - symbols[i] = symbols_sorted[i]; - free (symbols_sorted + ntokens); + symbols[i] = symbols_sorted[i - ntokens]; + free (symbols_sorted); } { @@ -323,15 +325,16 @@ nonterminals_reduce (void) item_number *rhsp; for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp) if (ISVAR (*rhsp)) - *rhsp = symbol_number_as_item_number (nontermmap[*rhsp]); + *rhsp = symbol_number_as_item_number (nontermmap[*rhsp + - ntokens]); } - accept->number = nontermmap[accept->number]; + accept->number = nontermmap[accept->number - ntokens]; } nsyms -= nuseless_nonterminals; nvars -= nuseless_nonterminals; - free (nontermmap + ntokens); + free (nontermmap); } @@ -345,7 +348,7 @@ reduce_output (FILE *out) if (nuseless_nonterminals > 0) { int i; - fprintf (out, "%s\n\n", _("Useless nonterminals")); + fprintf (out, "%s\n\n", _("Nonterminals useless in grammar")); for (i = 0; i < nuseless_nonterminals; ++i) fprintf (out, " %s\n", symbols[nsyms + i]->tag); fputs ("\n\n", out); @@ -355,10 +358,10 @@ reduce_output (FILE *out) bool b = false; int i; for (i = 0; i < ntokens; i++) - if (!bitset_test (V, i) && !bitset_test (V1, i)) + if (reduce_token_unused_in_grammar (i)) { if (!b) - fprintf (out, "%s\n\n", _("Terminals which are not used")); + fprintf (out, "%s\n\n", _("Terminals unused in grammar")); b = true; fprintf (out, " %s\n", symbols[i]->tag); } @@ -367,14 +370,11 @@ reduce_output (FILE *out) } if (nuseless_productions > 0) - grammar_rules_partial_print (out, _("Useless rules"), - rule_useless_p); + grammar_rules_partial_print (out, _("Rules useless in grammar"), + rule_useless_in_grammar_p); } - - - /*-------------------------------. | Report the results to STDERR. | `-------------------------------*/ @@ -382,30 +382,24 @@ reduce_output (FILE *out) static void reduce_print (void) { - if (yacc_flag && nuseless_productions) - fprintf (stderr, ngettext ("%d rule never reduced\n", - "%d rules never reduced\n", - nuseless_productions), - nuseless_productions); - - fprintf (stderr, "%s: %s: ", grammar_file, _("warning")); - if (nuseless_nonterminals > 0) - fprintf (stderr, ngettext ("%d useless nonterminal", - "%d useless nonterminals", - nuseless_nonterminals), - nuseless_nonterminals); - - if (nuseless_nonterminals > 0 && nuseless_productions > 0) - fprintf (stderr, _(" and ")); - + { + fprintf (stderr, "%s: %s: ", grammar_file, _("warning")); + fprintf (stderr, ngettext ("%d nonterminal useless in grammar", + "%d nonterminals useless in grammar", + nuseless_nonterminals), + nuseless_nonterminals); + fprintf (stderr, "\n"); + } if (nuseless_productions > 0) - fprintf (stderr, ngettext ("%d useless rule", - "%d useless rules", - nuseless_productions), - nuseless_productions); - fprintf (stderr, "\n"); - fflush (stderr); + { + fprintf (stderr, "%s: %s: ", grammar_file, _("warning")); + fprintf (stderr, ngettext ("%d rule useless in grammar", + "%d rules useless in grammar", + nuseless_productions), + nuseless_productions); + fprintf (stderr, "\n"); + } } void @@ -423,7 +417,7 @@ reduce_grammar (void) useless_nonterminals (); inaccessable_symbols (); - reduced = (bool) (nuseless_nonterminals + nuseless_productions > 0); + reduced = (nuseless_nonterminals + nuseless_productions > 0); if (!reduced) return; @@ -452,6 +446,19 @@ reduce_grammar (void) } } +bool +reduce_token_unused_in_grammar (symbol_number i) +{ + aver (i < ntokens); + return !bitset_test (V, i) && !bitset_test (V1, i); +} + +bool +reduce_nonterminal_useless_in_grammar (symbol_number i) +{ + aver (ntokens <= i && i < nsyms + nuseless_nonterminals); + return nsyms <= i; +} /*-----------------------------------------------------------. | Free the global sets used to compute the reduced grammar. |