X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/2cec9080f685192e231333686b411fb524239a1b..0e16927b48c881317a38132923b6f3150802a7d3:/src/print.c diff --git a/src/print.c b/src/print.c index cb1600c9..cb227aa5 100644 --- a/src/print.c +++ b/src/print.c @@ -1,30 +1,27 @@ /* Print information on generated parser, for bison, - Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002, 2003, 2004, 2005 - Free Software Foundation, Inc. + Copyright (C) 1984, 1986, 1989, 2000-2005, 2007, 2009-2012 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., 51 Franklin Street, Fifth Floor, - Boston, MA 02110-1301, USA. */ + along with this program. If not, see . */ #include #include "system.h" #include -#include #include "LR0.h" #include "closure.h" @@ -33,14 +30,15 @@ #include "getargs.h" #include "gram.h" #include "lalr.h" +#include "muscle-tab.h" #include "print.h" #include "reader.h" #include "reduce.h" #include "state.h" #include "symtab.h" +#include "tables.h" -static bitset shift_set; -static bitset look_ahead_set; +static bitset no_reduce_set; #if 0 static void @@ -81,7 +79,7 @@ print_core (FILE *out, state *s) { closure (sitems, snritems); sitems = itemset; - snritems = nritemset; + snritems = nitemset; } if (!snritems) @@ -111,9 +109,10 @@ print_core (FILE *out, state *s) for (/* Nothing */; *sp >= 0; ++sp) fprintf (out, " %s", symbols[*sp]->tag); - /* Display the look-ahead tokens? */ - if (report_flag & report_look_ahead_tokens) - state_rule_look_ahead_tokens_print (s, &rules[r], out); + /* Display the lookahead tokens? */ + if (report_flag & report_lookahead_tokens + && item_number_is_rule_number (*sp1)) + state_rule_lookahead_tokens_print (s, &rules[r], out); fputc ('\n', out); } @@ -132,7 +131,7 @@ print_transitions (state *s, FILE *out, bool display_transitions_p) size_t width = 0; int i; - /* Compute the width of the look-ahead token column. */ + /* Compute the width of the lookahead token column. */ for (i = 0; i < trans->num; i++) if (!TRANSITION_IS_DISABLED (trans, i) && TRANSITION_IS_SHIFT (trans, i) == display_transitions_p) @@ -148,7 +147,7 @@ print_transitions (state *s, FILE *out, bool display_transitions_p) fputc ('\n', out); width += 2; - /* Report look-ahead tokens and shifts. */ + /* Report lookahead tokens and shifts. */ for (i = 0; i < trans->num; i++) if (!TRANSITION_IS_DISABLED (trans, i) && TRANSITION_IS_SHIFT (trans, i) == display_transitions_p) @@ -180,7 +179,7 @@ print_errs (FILE *out, state *s) size_t width = 0; int i; - /* Compute the width of the look-ahead token column. */ + /* Compute the width of the lookahead token column. */ for (i = 0; i < errp->num; ++i) if (errp->symbols[i]) max_length (&width, errp->symbols[i]->tag); @@ -192,7 +191,7 @@ print_errs (FILE *out, state *s) fputc ('\n', out); width += 2; - /* Report look-ahead tokens and errors. */ + /* Report lookahead tokens and errors. */ for (i = 0; i < errp->num; ++i) if (errp->symbols[i]) { @@ -206,85 +205,20 @@ print_errs (FILE *out, state *s) } -/*-------------------------------------------------------------. -| Return the default rule of S if it has one, NULL otherwise. | -`-------------------------------------------------------------*/ - -static rule * -state_default_rule (state *s) -{ - reductions *reds = s->reductions; - rule *default_rule = NULL; - int cmax = 0; - int i; - - /* No need for a look-ahead. */ - if (s->consistent) - return reds->rules[0]; - - /* 1. Each reduction is possibly masked by the look-ahead tokens on which - we shift (S/R conflicts)... */ - bitset_zero (shift_set); - { - transitions *trans = s->transitions; - FOR_EACH_SHIFT (trans, i) - { - /* If this state has a shift for the error token, don't use a - default rule. */ - if (TRANSITION_IS_ERROR (trans, i)) - return NULL; - bitset_set (shift_set, TRANSITION_SYMBOL (trans, i)); - } - } - - /* 2. Each reduction is possibly masked by the look-ahead tokens on which - we raise an error (due to %nonassoc). */ - { - errs *errp = s->errs; - for (i = 0; i < errp->num; i++) - if (errp->symbols[i]) - bitset_set (shift_set, errp->symbols[i]->number); - } - - for (i = 0; i < reds->num; ++i) - { - int count = 0; - - /* How many non-masked look-ahead tokens are there for this - reduction? */ - bitset_andn (look_ahead_set, reds->look_ahead_tokens[i], shift_set); - count = bitset_count (look_ahead_set); - - if (count > cmax) - { - cmax = count; - default_rule = reds->rules[i]; - } - - /* 3. And finally, each reduction is possibly masked by previous - reductions (in R/R conflicts, we keep the first reductions). - */ - bitset_or (shift_set, shift_set, reds->look_ahead_tokens[i]); - } - - return default_rule; -} - - -/*--------------------------------------------------------------------------. -| Report a reduction of RULE on LOOK_AHEAD_TOKEN (which can be `default'). | -| If not ENABLED, the rule is masked by a shift or a reduce (S/R and | -| R/R conflicts). | -`--------------------------------------------------------------------------*/ +/*-------------------------------------------------------------------------. +| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be `default'). | +| If not ENABLED, the rule is masked by a shift or a reduce (S/R and | +| R/R conflicts). | +`-------------------------------------------------------------------------*/ static void print_reduction (FILE *out, size_t width, - const char *look_ahead_token, + const char *lookahead_token, rule *r, bool enabled) { int j; - fprintf (out, " %s", look_ahead_token); - for (j = width - strlen (look_ahead_token); j > 0; --j) + fprintf (out, " %s", lookahead_token); + for (j = width - strlen (lookahead_token); j > 0; --j) fputc (' ', out); if (!enabled) fputc ('[', out); @@ -307,34 +241,39 @@ print_reductions (FILE *out, state *s) { transitions *trans = s->transitions; reductions *reds = s->reductions; - rule *default_rule = NULL; + rule *default_reduction = NULL; size_t width = 0; int i, j; + bool default_reduction_only = true; if (reds->num == 0) return; - default_rule = state_default_rule (s); + if (yydefact[s->number] != 0) + default_reduction = &rules[yydefact[s->number] - 1]; - bitset_zero (shift_set); + bitset_zero (no_reduce_set); FOR_EACH_SHIFT (trans, i) - bitset_set (shift_set, TRANSITION_SYMBOL (trans, i)); + bitset_set (no_reduce_set, TRANSITION_SYMBOL (trans, i)); + for (i = 0; i < s->errs->num; ++i) + if (s->errs->symbols[i]) + bitset_set (no_reduce_set, s->errs->symbols[i]->number); - /* Compute the width of the look-ahead token column. */ - if (default_rule) + /* Compute the width of the lookahead token column. */ + if (default_reduction) width = strlen (_("$default")); - if (reds->look_ahead_tokens) + if (reds->lookahead_tokens) for (i = 0; i < ntokens; i++) { - bool count = bitset_test (shift_set, i); + bool count = bitset_test (no_reduce_set, i); for (j = 0; j < reds->num; ++j) - if (bitset_test (reds->look_ahead_tokens[j], i)) + if (bitset_test (reds->lookahead_tokens[j], i)) { if (! count) { - if (reds->rules[j] != default_rule) + if (reds->rules[j] != default_reduction) max_length (&width, symbols[i]->tag); count = true; } @@ -352,32 +291,38 @@ print_reductions (FILE *out, state *s) fputc ('\n', out); width += 2; - /* Report look-ahead tokens (or $default) and reductions. */ - if (reds->look_ahead_tokens) + /* Report lookahead tokens (or $default) and reductions. */ + if (reds->lookahead_tokens) for (i = 0; i < ntokens; i++) { bool defaulted = false; - bool count = bitset_test (shift_set, i); + bool count = bitset_test (no_reduce_set, i); + if (count) + default_reduction_only = false; for (j = 0; j < reds->num; ++j) - if (bitset_test (reds->look_ahead_tokens[j], i)) + if (bitset_test (reds->lookahead_tokens[j], i)) { if (! count) { - if (reds->rules[j] != default_rule) - print_reduction (out, width, - symbols[i]->tag, - reds->rules[j], true); + if (reds->rules[j] != default_reduction) + { + default_reduction_only = false; + print_reduction (out, width, + symbols[i]->tag, + reds->rules[j], true); + } else defaulted = true; count = true; } else { + default_reduction_only = false; if (defaulted) print_reduction (out, width, symbols[i]->tag, - default_rule, true); + default_reduction, true); defaulted = false; print_reduction (out, width, symbols[i]->tag, @@ -386,9 +331,17 @@ print_reductions (FILE *out, state *s) } } - if (default_rule) - print_reduction (out, width, - _("$default"), default_rule, true); + if (default_reduction) + { + char *default_reductions = + muscle_percent_define_get ("lr.default-reductions"); + print_reduction (out, width, _("$default"), default_reduction, true); + aver (0 == strcmp (default_reductions, "most") + || (0 == strcmp (default_reductions, "consistent") + && default_reduction_only) + || (reds->num == 1 && reds->rules[0]->number == 0)); + free (default_reductions); + } } @@ -464,7 +417,7 @@ print_grammar (FILE *out) buffer[0] = 0; column = strlen (tag); fputs (tag, out); - END_TEST (50); + END_TEST (65); sprintf (buffer, " (%d)", i); for (r = 0; r < nrules; r++) @@ -508,14 +461,16 @@ print_grammar (FILE *out) if (left_count > 0) { - END_TEST (50); + END_TEST (65); sprintf (buffer + strlen (buffer), _(" on left:")); for (r = 0; r < nrules; r++) { - END_TEST (65); if (rules[r].lhs->number == i) - sprintf (buffer + strlen (buffer), " %d", r); + { + END_TEST (65); + sprintf (buffer + strlen (buffer), " %d", r); + } } } @@ -523,7 +478,7 @@ print_grammar (FILE *out) { if (left_count > 0) sprintf (buffer + strlen (buffer), ","); - END_TEST (50); + END_TEST (65); sprintf (buffer + strlen (buffer), _(" on right:")); for (r = 0; r < nrules; r++) { @@ -552,7 +507,8 @@ print_results (void) reduce_output (out); grammar_rules_partial_print (out, - _("Rules never reduced"), rule_never_reduced_p); + _("Rules useless in parser due to conflicts"), + rule_useless_in_parser_p); conflicts_output (out); print_grammar (out); @@ -562,12 +518,10 @@ print_results (void) if (report_flag & report_itemsets) new_closure (nritems); /* Storage for print_reductions. */ - shift_set = bitset_create (ntokens, BITSET_FIXED); - look_ahead_set = bitset_create (ntokens, BITSET_FIXED); + no_reduce_set = bitset_create (ntokens, BITSET_FIXED); for (i = 0; i < nstates; i++) print_state (out, states[i]); - bitset_free (shift_set); - bitset_free (look_ahead_set); + bitset_free (no_reduce_set); if (report_flag & report_itemsets) free_closure ();