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/* Print information on generated parser, for bison,
Copyright (C) 1984, 1986, 1989, 2000-2005, 2007, 2009-2015, 2018-2021
Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
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 3 of the License, or
(at your option) any later version.
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 this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
#include "print.h"
#include "system.h"
#include <bitset.h>
#include <mbswidth.h>
#include "closure.h"
#include "complain.h"
#include "conflicts.h"
#include "counterexample.h"
#include "files.h"
#include "getargs.h"
#include "gram.h"
#include "lalr.h"
#include "lr0.h"
#include "muscle-tab.h"
#include "reader.h"
#include "reduce.h"
#include "state.h"
#include "symtab.h"
#include "tables.h"
/* For a given state, the symbol numbers of the lookahead tokens for
shifts and errors (i.e. not reduce). */
static bitset no_reduce_set;
/*---------------------------------------.
| *WIDTH := max (*WIDTH, strlen (STR)). |
`---------------------------------------*/
static void
max_length (size_t *width, const char *str)
{
size_t len = mbswidth (str, 0);
if (len > *width)
*width = len;
}
/*--------------------------------.
| Report information on a state. |
`--------------------------------*/
static void
print_core (FILE *out, const state *s)
{
const item_index *sitems = s->items;
size_t snritems = s->nitems;
/* Output all the items of a state, not only its kernel. */
if (report_flag & report_itemsets)
{
closure (sitems, snritems);
sitems = itemset;
snritems = nitemset;
}
if (!snritems)
return;
fputc ('\n', out);
rule const *previous_rule = NULL;
for (size_t i = 0; i < snritems; i++)
{
item_number *sp1 = ritem + sitems[i];
rule const *r = item_rule (sp1);
item_print (sp1, previous_rule, out);
previous_rule = r;
/* Display the lookahead tokens? */
if (report_flag & report_lookaheads
&& item_number_is_rule_number (*sp1))
state_rule_lookaheads_print (s, r, out);
fputc ('\n', out);
}
}
/*------------------------------------------------------------.
| Report the shifts iff DISPLAY_SHIFTS_P or the gotos of S on |
| OUT. |
`------------------------------------------------------------*/
static void
print_transitions (const state *s, FILE *out, bool display_transitions_p)
{
transitions *trans = s->transitions;
size_t width = 0;
/* Compute the width of the lookahead token column. */
for (int i = 0; i < trans->num; i++)
if (!TRANSITION_IS_DISABLED (trans, i)
&& TRANSITION_IS_SHIFT (trans, i) == display_transitions_p)
{
symbol *sym = symbols[TRANSITION_SYMBOL (trans, i)];
max_length (&width, sym->tag);
}
/* Nothing to report. */
if (!width)
return;
fputc ('\n', out);
width += 2;
/* Report lookahead tokens and shifts. */
for (int i = 0; i < trans->num; i++)
if (!TRANSITION_IS_DISABLED (trans, i)
&& TRANSITION_IS_SHIFT (trans, i) == display_transitions_p)
{
symbol *sym = symbols[TRANSITION_SYMBOL (trans, i)];
const char *tag = sym->tag;
const state *s1 = trans->states[i];
fprintf (out, " %s", tag);
for (int j = width - mbswidth (tag, 0); j > 0; --j)
fputc (' ', out);
if (display_transitions_p)
fprintf (out, _("shift, and go to state %d\n"), s1->number);
else
fprintf (out, _("go to state %d\n"), s1->number);
}
}
/*--------------------------------------------------------.
| Report the explicit errors of S raised from %nonassoc. |
`--------------------------------------------------------*/
static void
print_errs (FILE *out, const state *s)
{
errs *errp = s->errs;
size_t width = 0;
/* Compute the width of the lookahead token column. */
for (int i = 0; i < errp->num; ++i)
if (errp->symbols[i])
max_length (&width, errp->symbols[i]->tag);
/* Nothing to report. */
if (!width)
return;
fputc ('\n', out);
width += 2;
/* Report lookahead tokens and errors. */
for (int i = 0; i < errp->num; ++i)
if (errp->symbols[i])
{
const char *tag = errp->symbols[i]->tag;
fprintf (out, " %s", tag);
for (int j = width - mbswidth (tag, 0); j > 0; --j)
fputc (' ', out);
fputs (_("error (nonassociative)\n"), out);
}
}
/*-------------------------------------------------------------------.
| Report a reduction of RULE on LOOKAHEAD (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 *lookahead,
rule *r, bool enabled)
{
fprintf (out, " %s", lookahead);
for (int j = width - mbswidth (lookahead, 0); j > 0; --j)
fputc (' ', out);
if (!enabled)
fputc ('[', out);
if (rule_is_initial (r))
fprintf (out, _("accept"));
else
fprintf (out, _("reduce using rule %d (%s)"), r->number,
r->lhs->symbol->tag);
if (!enabled)
fputc (']', out);
fputc ('\n', out);
}
/*-------------------------------------------.
| Report on OUT the reduction actions of S. |
`-------------------------------------------*/
static void
print_reductions (FILE *out, const state *s)
{
reductions *reds = s->reductions;
if (reds->num == 0)
return;
rule *default_reduction = NULL;
if (yydefact[s->number] != 0)
default_reduction = &rules[yydefact[s->number] - 1];
transitions *trans = s->transitions;
bitset_zero (no_reduce_set);
{
int i;
FOR_EACH_SHIFT (trans, i)
bitset_set (no_reduce_set, TRANSITION_SYMBOL (trans, i));
}
for (int i = 0; i < s->errs->num; ++i)
if (s->errs->symbols[i])
bitset_set (no_reduce_set, s->errs->symbols[i]->content->number);
/* Compute the width of the lookahead token column. */
size_t width = 0;
if (default_reduction)
width = mbswidth (_("$default"), 0);
if (reds->lookaheads)
for (int i = 0; i < ntokens; i++)
{
bool count = bitset_test (no_reduce_set, i);
for (int j = 0; j < reds->num; ++j)
if (bitset_test (reds->lookaheads[j], i))
{
if (! count)
{
if (reds->rules[j] != default_reduction)
max_length (&width, symbols[i]->tag);
count = true;
}
else
max_length (&width, symbols[i]->tag);
}
}
/* Nothing to report. */
if (!width)
return;
fputc ('\n', out);
width += 2;
bool default_reduction_only = true;
/* Report lookahead tokens (or $default) and reductions. */
if (reds->lookaheads)
for (int i = 0; i < ntokens; i++)
{
bool defaulted = false;
bool count = bitset_test (no_reduce_set, i);
if (count)
default_reduction_only = false;
for (int j = 0; j < reds->num; ++j)
if (bitset_test (reds->lookaheads[j], i))
{
if (! count)
{
if (reds->rules[j] != default_reduction)
{
default_reduction_only = false;
print_reduction (out, width,
symbols[i]->tag,
reds->rules[j], true);
}
else
defaulted = true;
count = true;
}
else
{
default_reduction_only = false;
if (defaulted)
print_reduction (out, width,
symbols[i]->tag,
default_reduction, true);
defaulted = false;
print_reduction (out, width,
symbols[i]->tag,
reds->rules[j], false);
}
}
}
if (default_reduction)
{
char *default_reductions =
muscle_percent_define_get ("lr.default-reduction");
print_reduction (out, width, _("$default"), default_reduction, true);
aver (STREQ (default_reductions, "most")
|| (STREQ (default_reductions, "consistent")
&& default_reduction_only)
|| (reds->num == 1 && rule_is_initial (reds->rules[0])));
(void) default_reduction_only;
free (default_reductions);
}
}
/*--------------------------------------------------------------.
| Report on OUT all the actions (shifts, gotos, reductions, and |
| explicit errors from %nonassoc) of S. |
`--------------------------------------------------------------*/
static void
print_actions (FILE *out, const state *s)
{
/* Print shifts. */
print_transitions (s, out, true);
print_errs (out, s);
print_reductions (out, s);
/* Print gotos. */
print_transitions (s, out, false);
}
/*----------------------------------.
| Report all the data on S on OUT. |
`----------------------------------*/
static void
print_state (FILE *out, const state *s)
{
fputs ("\n\n", out);
fprintf (out, _("State %d"), s->number);
fputc ('\n', out);
print_core (out, s);
print_actions (out, s);
if ((report_flag & report_solved_conflicts) && s->solved_conflicts)
{
fputc ('\n', out);
fputs (s->solved_conflicts, out);
}
if (has_conflicts (s)
&& (report_flag & report_cex
|| warning_is_enabled (Wcounterexamples)))
{
fputc ('\n', out);
counterexample_report_state (s, out, " ");
}
}
/*-----------------------------------------.
| Print information on the whole grammar. |
`-----------------------------------------*/
static void
print_terminal_symbols (FILE *out)
{
/* TERMINAL (type #) : rule #s terminal is on RHS */
fprintf (out, "%s\n\n", _("Terminals, with rules where they appear"));
for (int i = 0; i < max_code + 1; ++i)
if (token_translations[i] != undeftoken->content->number)
{
const symbol *sym = symbols[token_translations[i]];
const char *tag = sym->tag;
fprintf (out, "%4s%s", "", tag);
if (sym->content->type_name)
fprintf (out, " <%s>", sym->content->type_name);
fprintf (out, " (%d)", i);
for (rule_number r = 0; r < nrules; r++)
for (item_number *rhsp = rules[r].rhs; *rhsp >= 0; rhsp++)
if (item_number_as_symbol_number (*rhsp) == token_translations[i])
{
fprintf (out, " %d", r);
break;
}
fputc ('\n', out);
}
fputs ("\n\n", out);
}
static void
print_nonterminal_symbols (FILE *out)
{
fprintf (out, "%s\n\n", _("Nonterminals, with rules where they appear"));
for (symbol_number i = ntokens; i < nsyms; i++)
{
const symbol *sym = symbols[i];
const char *tag = sym->tag;
bool on_left = false;
bool on_right = false;
for (rule_number r = 0; r < nrules; r++)
{
on_left |= rules[r].lhs->number == i;
for (item_number *rhsp = rules[r].rhs; !on_right && 0 <= *rhsp; ++rhsp)
on_right |= item_number_as_symbol_number (*rhsp) == i;
if (on_left && on_right)
break;
}
int column = 4 + mbswidth (tag, 0);
fprintf (out, "%4s%s", "", tag);
if (sym->content->type_name)
column += fprintf (out, " <%s>",
sym->content->type_name);
fprintf (out, " (%d)\n", i);
if (on_left)
{
fprintf (out, "%8s%s", "", _("on left:"));
for (rule_number r = 0; r < nrules; r++)
if (rules[r].lhs->number == i)
fprintf (out, " %d", r);
fputc ('\n', out);
}
if (on_right)
{
fprintf (out, "%8s%s", "", _("on right:"));
for (rule_number r = 0; r < nrules; r++)
for (item_number *rhsp = rules[r].rhs; 0 <= *rhsp; ++rhsp)
if (item_number_as_symbol_number (*rhsp) == i)
{
fprintf (out, " %d", r);
break;
}
fputc ('\n', out);
}
}
}
void
print_results (void)
{
/* We used to use just .out if SPEC_NAME_PREFIX (-p) was used, but
that conflicts with Posix. */
FILE *out = xfopen (spec_verbose_file, "w");
reduce_output (out);
grammar_rules_partial_print (out,
_("Rules useless in parser due to conflicts"),
rule_useless_in_parser_p);
conflicts_output (out);
grammar_rules_print (out);
print_terminal_symbols (out);
print_nonterminal_symbols (out);
/* Storage for print_reductions. */
no_reduce_set = bitset_create (ntokens, BITSET_FIXED);
for (state_number i = 0; i < nstates; i++)
print_state (out, states[i]);
bitset_free (no_reduce_set);
xfclose (out);
}