/* Find and resolve or report look-ahead conflicts for bison,
- Copyright (C) 1984, 1989 Free Software Foundation, Inc.
+ Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002
+ Free Software Foundation, Inc.
-This file is part of Bison, the GNU Compiler Compiler.
+ This file is part of Bison, the GNU Compiler Compiler.
-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.
+ 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.
-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 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ 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. */
-#ifdef _AIX
- #pragma alloca
-#endif
-#include <stdio.h>
#include "system.h"
-#include "machine.h"
-#include "new.h"
+#include "bitset.h"
+#include "complain.h"
+#include "getargs.h"
+#include "symtab.h"
#include "files.h"
#include "gram.h"
#include "state.h"
+#include "lalr.h"
+#include "conflicts.h"
+#include "reader.h"
+#include "LR0.h"
+
+/* -1 stands for not specified. */
+int expected_conflicts = -1;
+static char *conflicts = NULL;
+struct obstack solved_conflicts_obstack;
+
+static bitset shiftset;
+static bitset lookaheadset;
+
+\f
+
+enum conflict_resolution_e
+ {
+ shift_resolution,
+ reduce_resolution,
+ left_resolution,
+ right_resolution,
+ nonassoc_resolution
+ };
+
+
+/*----------------------------------------------------------------.
+| Explain how an SR conflict between TOKEN and RULE was resolved: |
+| RESOLUTION. |
+`----------------------------------------------------------------*/
+
+static inline void
+log_resolution (rule_t *rule, symbol_number_t token,
+ enum conflict_resolution_e resolution)
+{
+ if (report_flag & report_solved_conflicts)
+ {
+ /* The description of the resolution. */
+ switch (resolution)
+ {
+ case shift_resolution:
+ case right_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ _("\
+ Conflict between rule %d and token %s resolved as shift"),
+ rule->number,
+ symbols[token]->tag);
+ break;
+ case reduce_resolution:
+ case left_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ _("\
+ Conflict between rule %d and token %s resolved as reduce"),
+ rule->number,
+ symbols[token]->tag);
+ break;
+ case nonassoc_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ _("\
+ Conflict between rule %d and token %s resolved as an error"),
+ rule->number,
+ symbols[token]->tag);
+ break;
+ }
+ /* The reason. */
+ switch (resolution)
+ {
+ case shift_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ " (%s < %s)",
+ rule->prec->tag,
+ symbols[token]->tag);
+ break;
+
+ case reduce_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ " (%s < %s)",
+ symbols[token]->tag,
+ rule->prec->tag);
+ break;
+
+ case left_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%left %s)",
+ symbols[token]->tag);
+ break;
+
+ case right_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%right %s)",
+ symbols[token]->tag);
+ break;
+ case nonassoc_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%nonassoc %s)",
+ symbols[token]->tag);
+ break;
+ }
+ obstack_sgrow (&solved_conflicts_obstack, ".\n");
+ }
+}
-#ifndef __GNUC__
-#undef alloca
-#define alloca __builtin_alloca
-#else
-#ifdef HAVE_ALLOCA_H
-#include <alloca.h>
-#else
-#ifndef _AIX
-extern char *alloca ();
-#endif
-#endif
-#endif
-
-extern char **tags;
-extern int tokensetsize;
-extern char *consistent;
-extern short *accessing_symbol;
-extern shifts **shift_table;
-extern unsigned *LA;
-extern short *LAruleno;
-extern short *lookaheads;
-extern int verboseflag;
-
-void set_conflicts();
-void resolve_sr_conflict();
-void flush_shift();
-void log_resolution();
-void total_conflicts();
-void count_sr_conflicts();
-void count_rr_conflicts();
-
-char any_conflicts;
-char *conflicts;
-errs **err_table;
-int expected_conflicts;
-
-
-static unsigned *shiftset;
-static unsigned *lookaheadset;
-static int src_total;
-static int rrc_total;
-static int src_count;
-static int rrc_count;
+/*------------------------------------------------------------------.
+| Turn off the shift recorded for the specified token in the |
+| specified state. Used when we resolve a shift-reduce conflict in |
+| favor of the reduction. |
+`------------------------------------------------------------------*/
-void
-initialize_conflicts()
+static void
+flush_shift (state_t *state, int token)
{
- register int i;
-/* register errs *sp; JF unused */
-
- conflicts = NEW2(nstates, char);
- shiftset = NEW2(tokensetsize, unsigned);
- lookaheadset = NEW2(tokensetsize, unsigned);
+ transitions_t *transitions = state->transitions;
+ int i;
+
+ bitset_reset (lookaheadset, token);
+ for (i = 0; i < transitions->num; i++)
+ if (!TRANSITION_IS_DISABLED (transitions, i)
+ && TRANSITION_SYMBOL (transitions, i) == token)
+ TRANSITION_DISABLE (transitions, i);
+}
- err_table = NEW2(nstates, errs *);
- any_conflicts = 0;
+/*-------------------------------------------------------------------.
+| Turn off the reduce recorded for the specified token for the |
+| specified lookahead. Used when we resolve a shift-reduce conflict |
+| in favor of the shift. |
+`-------------------------------------------------------------------*/
- for (i = 0; i < nstates; i++)
- set_conflicts(i);
+static void
+flush_reduce (bitset lookaheads, int token)
+{
+ bitset_reset (lookaheads, token);
}
-void
-set_conflicts(state)
-int state;
+/*------------------------------------------------------------------.
+| Attempt to resolve shift-reduce conflict for one rule by means of |
+| precedence declarations. It has already been checked that the |
+| rule has a precedence. A conflict is resolved by modifying the |
+| shift or reduce tables so that there is no longer a conflict. |
+| |
+| LOOKAHEAD is the number of the lookahead bitset to consider. |
+| |
+| ERRS can be used to store discovered explicit errors. |
+`------------------------------------------------------------------*/
+
+static void
+resolve_sr_conflict (state_t *state, int ruleno,
+ symbol_t **errs)
{
- register int i;
- register int k;
- register shifts *shiftp;
- register unsigned *fp2;
- register unsigned *fp3;
- register unsigned *fp4;
- register unsigned *fp1;
- register int symbol;
-
- if (consistent[state]) return;
-
- for (i = 0; i < tokensetsize; i++)
- lookaheadset[i] = 0;
-
- shiftp = shift_table[state];
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(lookaheadset, symbol);
- }
- }
-
- k = lookaheads[state + 1];
- fp4 = lookaheadset + tokensetsize;
+ symbol_number_t i;
+ reductions_t *reds = state->reductions;
+ /* Find the rule to reduce by to get precedence of reduction. */
+ rule_t *redrule = reds->rules[ruleno];
+ int redprec = redrule->prec->prec;
+ bitset lookaheads = reds->lookaheads[ruleno];
+ int nerrs = 0;
- /* loop over all rules which require lookahead in this state */
- /* first check for shift-reduce conflict, and try to resolve using precedence */
-
- for (i = lookaheads[state]; i < k; i++)
- if (rprec[LAruleno[i]])
+ for (i = 0; i < ntokens; i++)
+ if (bitset_test (lookaheads, i)
+ && bitset_test (lookaheadset, i)
+ && symbols[i]->prec)
{
- fp1 = LA + i * tokensetsize;
- fp2 = fp1;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
+ /* Shift-reduce conflict occurs for token number i
+ and it has a precedence.
+ The precedence of shifting is that of token i. */
+ if (symbols[i]->prec < redprec)
{
- if (*fp2++ & *fp3++)
- {
- resolve_sr_conflict(state, i);
- break;
- }
+ log_resolution (redrule, i, reduce_resolution);
+ flush_shift (state, i);
}
- }
-
- /* loop over all rules which require lookahead in this state */
- /* Check for conflicts not resolved above. */
-
- for (i = lookaheads[state]; i < k; i++)
- {
- fp1 = LA + i * tokensetsize;
- fp2 = fp1;
- fp3 = lookaheadset;
+ else if (symbols[i]->prec > redprec)
+ {
+ log_resolution (redrule, i, shift_resolution);
+ flush_reduce (lookaheads, i);
+ }
+ else
+ /* Matching precedence levels.
+ For left association, keep only the reduction.
+ For right association, keep only the shift.
+ For nonassociation, keep neither. */
- while (fp3 < fp4)
- {
- if (*fp2++ & *fp3++)
+ switch (symbols[i]->assoc)
{
- conflicts[state] = 1;
- any_conflicts = 1;
+ case right_assoc:
+ log_resolution (redrule, i, right_resolution);
+ flush_reduce (lookaheads, i);
+ break;
+
+ case left_assoc:
+ log_resolution (redrule, i, left_resolution);
+ flush_shift (state, i);
+ break;
+
+ case non_assoc:
+ log_resolution (redrule, i, nonassoc_resolution);
+ flush_shift (state, i);
+ flush_reduce (lookaheads, i);
+ /* Record an explicit error for this token. */
+ errs[nerrs++] = symbols[i];
+ break;
+
+ case undef_assoc:
+ assert (symbols[i]->assoc != undef_assoc);
+ break;
}
- }
+ }
- fp2 = fp1;
- fp3 = lookaheadset;
+ /* Some tokens have been explicitly made errors. Allocate a
+ permanent errs structure for this state, to record them. */
+ state_errs_set (state, nerrs, errs);
- while (fp3 < fp4)
- *fp3++ |= *fp2++;
+ if (obstack_object_size (&solved_conflicts_obstack))
+ {
+ obstack_1grow (&solved_conflicts_obstack, '\0');
+ state->solved_conflicts = obstack_finish (&solved_conflicts_obstack);
}
}
+/*-------------------------------------------------------------------.
+| Solve the S/R conflicts of STATE using the |
+| precedence/associativity, and flag it inconsistent if it still has |
+| conflicts. ERRS can be used as storage to compute the list of |
+| lookaheads on which this STATE raises a parse error (%nonassoc). |
+`-------------------------------------------------------------------*/
-/* Attempt to resolve shift-reduce conflict for one rule
-by means of precedence declarations.
-It has already been checked that the rule has a precedence.
-A conflict is resolved by modifying the shift or reduce tables
-so that there is no longer a conflict. */
-
-void
-resolve_sr_conflict(state, lookaheadnum)
-int state;
-int lookaheadnum;
+static void
+set_conflicts (state_t *state, symbol_t **errs)
{
- register int i;
- register int mask;
- register unsigned *fp1;
- register unsigned *fp2;
- register int redprec;
- /* Extra parens avoid errors on Ultrix 4.3. */
- errs *errp = (errs *) alloca ((sizeof(errs) + ntokens * sizeof(short)));
- short *errtokens = errp->errs;
-
- /* find the rule to reduce by to get precedence of reduction */
- redprec = rprec[LAruleno[lookaheadnum]];
-
- mask = 1;
- fp1 = LA + lookaheadnum * tokensetsize;
- fp2 = lookaheadset;
- for (i = 0; i < ntokens; i++)
- {
- if ((mask & *fp2 & *fp1) && sprec[i])
- /* Shift-reduce conflict occurs for token number i
- and it has a precedence.
- The precedence of shifting is that of token i. */
- {
- if (sprec[i] < redprec)
- {
- if (verboseflag) log_resolution(state, lookaheadnum, i, "reduce");
- *fp2 &= ~mask; /* flush the shift for this token */
- flush_shift(state, i);
- }
- else if (sprec[i] > redprec)
- {
- if (verboseflag) log_resolution(state, lookaheadnum, i, "shift");
- *fp1 &= ~mask; /* flush the reduce for this token */
- }
- else
- {
- /* Matching precedence levels.
- For left association, keep only the reduction.
- For right association, keep only the shift.
- For nonassociation, keep neither. */
-
- switch (sassoc[i])
- {
-
- case RIGHT_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, "shift");
- break;
-
- case LEFT_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, "reduce");
- break;
-
- case NON_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, "an error");
- break;
- }
-
- if (sassoc[i] != RIGHT_ASSOC)
- {
- *fp2 &= ~mask; /* flush the shift for this token */
- flush_shift(state, i);
- }
- if (sassoc[i] != LEFT_ASSOC)
- {
- *fp1 &= ~mask; /* flush the reduce for this token */
- }
- if (sassoc[i] == NON_ASSOC)
- {
- /* Record an explicit error for this token. */
- *errtokens++ = i;
- }
- }
- }
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp2++; fp1++;
- }
- }
- errp->nerrs = errtokens - errp->errs;
- if (errp->nerrs)
- {
- /* Some tokens have been explicitly made errors. Allocate
- a permanent errs structure for this state, to record them. */
- i = (char *) errtokens - (char *) errp;
- err_table[state] = (errs *) xmalloc ((unsigned int)i);
- bcopy (errp, err_table[state], i);
- }
- else
- err_table[state] = 0;
-}
-
+ int i;
+ transitions_t *transitions = state->transitions;
+ reductions_t *reds = state->reductions;
+ if (state->consistent)
+ return;
-/* turn off the shift recorded for the specified token in the specified state.
-Used when we resolve a shift-reduce conflict in favor of the reduction. */
+ bitset_zero (lookaheadset);
-void
-flush_shift(state, token)
-int state;
-int token;
-{
- register shifts *shiftp;
- register int k, i;
-/* register unsigned symbol; JF unused */
+ FOR_EACH_SHIFT (transitions, i)
+ bitset_set (lookaheadset, TRANSITION_SYMBOL (transitions, i));
- shiftp = shift_table[state];
+ /* Loop over all rules which require lookahead in this state. First
+ check for shift-reduce conflict, and try to resolve using
+ precedence. */
+ for (i = 0; i < reds->num; ++i)
+ if (reds->rules[i]->prec && reds->rules[i]->prec->prec
+ && !bitset_disjoint_p (reds->lookaheads[i], lookaheadset))
+ {
+ resolve_sr_conflict (state, i, errs);
+ break;
+ }
- if (shiftp)
+ /* Loop over all rules which require lookahead in this state. Check
+ for conflicts not resolved above. */
+ for (i = 0; i < reds->num; ++i)
{
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (shiftp->shifts[i] && token == accessing_symbol[shiftp->shifts[i]])
- (shiftp->shifts[i]) = 0;
- }
+ if (!bitset_disjoint_p (reds->lookaheads[i], lookaheadset))
+ conflicts[state->number] = 1;
+
+ bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]);
}
}
-void
-log_resolution(state, LAno, token, resolution)
-int state, LAno, token;
-char *resolution;
-{
- fprintf(foutput,
- "Conflict in state %d between rule %d and token %s resolved as %s.\n",
- state, LAruleno[LAno], tags[token], resolution);
-}
-
+/*----------------------------------------------------------------.
+| Solve all the S/R conflicts using the precedence/associativity, |
+| and flag as inconsistent the states that still have conflicts. |
+`----------------------------------------------------------------*/
void
-conflict_log()
+conflicts_solve (void)
{
- register int i;
+ state_number_t i;
+ /* List of lookaheads on which we explicitly raise a parse error. */
+ symbol_t **errs = XMALLOC (symbol_t *, ntokens + 1);
- src_total = 0;
- rrc_total = 0;
+ conflicts = XCALLOC (char, nstates);
+ shiftset = bitset_create (ntokens, BITSET_FIXED);
+ lookaheadset = bitset_create (ntokens, BITSET_FIXED);
+ obstack_init (&solved_conflicts_obstack);
for (i = 0; i < nstates; i++)
{
- if (conflicts[i])
- {
- count_sr_conflicts(i);
- count_rr_conflicts(i);
- src_total += src_count;
- rrc_total += rrc_count;
- }
+ set_conflicts (states[i], errs);
+
+ /* For uniformity of the code, make sure all the states have a valid
+ `errs' member. */
+ if (!states[i]->errs)
+ states[i]->errs = errs_new (0, 0);
}
- total_conflicts();
+ free (errs);
}
-
-void
-verbose_conflict_log()
-{
- register int i;
- src_total = 0;
- rrc_total = 0;
+/*---------------------------------------------.
+| Count the number of shift/reduce conflicts. |
+`---------------------------------------------*/
- for (i = 0; i < nstates; i++)
- {
- if (conflicts[i])
- {
- count_sr_conflicts(i);
- count_rr_conflicts(i);
- src_total += src_count;
- rrc_total += rrc_count;
+static int
+count_sr_conflicts (state_t *state)
+{
+ int i;
+ int src_count = 0;
+ transitions_t *transitions = state->transitions;
+ reductions_t *reds = state->reductions;
- fprintf(foutput, "State %d contains", i);
+ if (!transitions)
+ return 0;
- if (src_count == 1)
- fprintf(foutput, " 1 shift/reduce conflict");
- else if (src_count > 1)
- fprintf(foutput, " %d shift/reduce conflicts", src_count);
+ bitset_zero (lookaheadset);
+ bitset_zero (shiftset);
- if (src_count > 0 && rrc_count > 0)
- fprintf(foutput, " and");
+ FOR_EACH_SHIFT (transitions, i)
+ bitset_set (shiftset, TRANSITION_SYMBOL (transitions, i));
- if (rrc_count == 1)
- fprintf(foutput, " 1 reduce/reduce conflict");
- else if (rrc_count > 1)
- fprintf(foutput, " %d reduce/reduce conflicts", rrc_count);
+ for (i = 0; i < reds->num; ++i)
+ bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]);
- putc('.', foutput);
- putc('\n', foutput);
- }
- }
+ bitset_and (lookaheadset, lookaheadset, shiftset);
- total_conflicts();
+ src_count = bitset_count (lookaheadset);
+
+ return src_count;
}
-void
-total_conflicts()
-{
- extern int fixed_outfiles;
+/*----------------------------------------------------------------.
+| Count the number of reduce/reduce conflicts. If ONE_PER_TOKEN, |
+| count one conflict for each token that has any reduce/reduce |
+| conflicts. Otherwise, count one conflict for each pair of |
+| conflicting reductions. |
++`----------------------------------------------------------------*/
- if (src_total == expected_conflicts && rrc_total == 0)
- return;
+static int
+count_rr_conflicts (state_t *state, int one_per_token)
+{
+ int i;
+ reductions_t *reds = state->reductions;
+ int rrc_count = 0;
- if (fixed_outfiles)
+ for (i = 0; i < ntokens; i++)
{
- /* If invoked under the name `yacc', use the output format
- specified by POSIX. */
- fprintf(stderr, "conflicts: ");
- if (src_total > 0)
- fprintf(stderr, " %d shift/reduce", src_total);
- if (src_total > 0 && rrc_total > 0)
- fprintf(stderr, ",");
- if (rrc_total > 0)
- fprintf(stderr, " %d reduce/reduce", rrc_total);
- putc('\n', stderr);
+ int count = 0;
+ int j;
+ for (j = 0; j < reds->num; ++j)
+ if (bitset_test (reds->lookaheads[j], i))
+ count++;
+
+ if (count >= 2)
+ rrc_count += one_per_token ? 1 : count-1;
}
- else
- {
- fprintf(stderr, "%s contains", infile);
-
- if (src_total == 1)
- fprintf(stderr, " 1 shift/reduce conflict");
- else if (src_total > 1)
- fprintf(stderr, " %d shift/reduce conflicts", src_total);
-
- if (src_total > 0 && rrc_total > 0)
- fprintf(stderr, " and");
-
- if (rrc_total == 1)
- fprintf(stderr, " 1 reduce/reduce conflict");
- else if (rrc_total > 1)
- fprintf(stderr, " %d reduce/reduce conflicts", rrc_total);
- putc('.', stderr);
- putc('\n', stderr);
- }
+ return rrc_count;
}
-void
-count_sr_conflicts(state)
-int state;
-{
- register int i;
- register int k;
- register int mask;
- register shifts *shiftp;
- register unsigned *fp1;
- register unsigned *fp2;
- register unsigned *fp3;
- register int symbol;
+/*--------------------------------------------------------------.
+| Return a human readable string which reports shift/reduce and |
+| reduce/reduce conflict numbers (SRC_NUM, RRC_NUM). |
+`--------------------------------------------------------------*/
- src_count = 0;
-
- shiftp = shift_table[state];
- if (!shiftp) return;
+static const char *
+conflict_report (int src_num, int rrc_num)
+{
+ static char res[4096];
+ char *cp = res;
- for (i = 0; i < tokensetsize; i++)
+ if (src_num >= 1)
{
- shiftset[i] = 0;
- lookaheadset[i] = 0;
+ sprintf (cp, ngettext ("%d shift/reduce conflict",
+ "%d shift/reduce conflicts", src_num), src_num);
+ cp += strlen (cp);
}
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
+ if (src_num > 0 && rrc_num > 0)
{
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(shiftset, symbol);
+ sprintf (cp, " %s ", _("and"));
+ cp += strlen (cp);
}
- k = lookaheads[state + 1];
- fp3 = lookaheadset + tokensetsize;
-
- for (i = lookaheads[state]; i < k; i++)
+ if (rrc_num >= 1)
{
- fp1 = LA + i * tokensetsize;
- fp2 = lookaheadset;
-
- while (fp2 < fp3)
- *fp2++ |= *fp1++;
+ sprintf (cp, ngettext ("%d reduce/reduce conflict",
+ "%d reduce/reduce conflicts", rrc_num), rrc_num);
+ cp += strlen (cp);
}
- fp1 = shiftset;
- fp2 = lookaheadset;
-
- while (fp2 < fp3)
- *fp2++ &= *fp1++;
-
- mask = 1;
- fp2 = lookaheadset;
- for (i = 0; i < ntokens; i++)
- {
- if (mask & *fp2)
- src_count++;
+ *cp++ = '\0';
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp2++;
- }
- }
+ return res;
}
-void
-count_rr_conflicts(state)
-int state;
-{
- register int i;
- register int j;
- register int count;
- register unsigned mask;
- register unsigned *baseword;
- register unsigned *wordp;
- register int m;
- register int n;
+/*----------------------------------------------------------------.
+| Same as above, but report the number of conflicts a` la POSIX. |
+`----------------------------------------------------------------*/
- rrc_count = 0;
+static void
+conflict_report_yacc (int src_num, int rrc_num)
+{
+ /* If invoked with `--yacc', use the output format specified by
+ POSIX. */
+ fprintf (stderr, _("conflicts: "));
+ if (src_num > 0)
+ fprintf (stderr, _(" %d shift/reduce"), src_num);
+ if (src_num > 0 && rrc_num > 0)
+ fprintf (stderr, ",");
+ if (rrc_num > 0)
+ fprintf (stderr, _(" %d reduce/reduce"), rrc_num);
+ putc ('\n', stderr);
+}
- m = lookaheads[state];
- n = lookaheads[state + 1];
- if (n - m < 2) return;
+/*-----------------------------------------------------------.
+| Output the detailed description of states with conflicts. |
+`-----------------------------------------------------------*/
- mask = 1;
- baseword = LA + m * tokensetsize;
- for (i = 0; i < ntokens; i++)
+void
+conflicts_output (FILE *out)
+{
+ bool printed_sth = false;
+ state_number_t i;
+ for (i = 0; i < nstates; i++)
{
- wordp = baseword;
-
- count = 0;
- for (j = m; j < n; j++)
- {
- if (mask & *wordp)
- count++;
-
- wordp += tokensetsize;
- }
-
- if (count >= 2) rrc_count++;
-
- mask <<= 1;
- if (mask == 0)
+ state_t *s = states[i];
+ if (conflicts[i])
{
- mask = 1;
- baseword++;
+ fprintf (out, _("State %d contains "), i);
+ fprintf (out, "%s.\n",
+ conflict_report (count_sr_conflicts (s),
+ count_rr_conflicts (s, true)));
+ printed_sth = true;
}
}
+ if (printed_sth)
+ fputs ("\n\n", out);
}
+/*--------------------------------------------------------.
+| Total the number of S/R and R/R conflicts. Unlike the |
+| code in conflicts_output, however, count EACH pair of |
+| reductions for the same state and lookahead as one |
+| conflict. |
+`--------------------------------------------------------*/
-void
-print_reductions(state)
-int state;
+int
+conflicts_total_count (void)
{
- register int i;
- register int j;
- register int k;
- register unsigned *fp1;
- register unsigned *fp2;
- register unsigned *fp3;
- register unsigned *fp4;
- register int rule;
- register int symbol;
- register unsigned mask;
- register int m;
- register int n;
- register int default_LA;
- register int default_rule;
- register int cmax;
- register int count;
- register shifts *shiftp;
- register errs *errp;
- int nodefault = 0;
-
- for (i = 0; i < tokensetsize; i++)
- shiftset[i] = 0;
-
- shiftp = shift_table[state];
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- /* if this state has a shift for the error token,
- don't use a default rule. */
- if (symbol == error_token_number) nodefault = 1;
- SETBIT(shiftset, symbol);
- }
- }
+ state_number_t i;
+ int count;
- errp = err_table[state];
- if (errp)
- {
- k = errp->nerrs;
- for (i = 0; i < k; i++)
- {
- if (! errp->errs[i]) continue;
- symbol = errp->errs[i];
- SETBIT(shiftset, symbol);
- }
- }
+ /* Conflicts by state. */
+ count = 0;
+ for (i = 0; i < nstates; i++)
+ if (conflicts[i])
+ {
+ count += count_sr_conflicts (states[i]);
+ count += count_rr_conflicts (states[i], false);
+ }
+ return count;
+}
- m = lookaheads[state];
- n = lookaheads[state + 1];
- if (n - m == 1 && ! nodefault)
- {
- default_rule = LAruleno[m];
+/*------------------------------------------.
+| Reporting the total number of conflicts. |
+`------------------------------------------*/
- fp1 = LA + m * tokensetsize;
- fp2 = shiftset;
- fp3 = lookaheadset;
- fp4 = lookaheadset + tokensetsize;
+void
+conflicts_print (void)
+{
+ /* Is the number of SR conflicts OK? Either EXPECTED_CONFLICTS is
+ not set, and then we want 0 SR, or else it is specified, in which
+ case we want equality. */
+ int src_ok = 0;
- while (fp3 < fp4)
- *fp3++ = *fp1++ & *fp2++;
+ int src_total = 0;
+ int rrc_total = 0;
- mask = 1;
- fp3 = lookaheadset;
+ /* Conflicts by state. */
+ {
+ state_number_t i;
- for (i = 0; i < ntokens; i++)
+ for (i = 0; i < nstates; i++)
+ if (conflicts[i])
{
- if (mask & *fp3)
- fprintf(foutput, " %-4s\t[reduce using rule %d (%s)]\n",
- tags[i], default_rule, tags[rlhs[default_rule]]);
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp3++;
- }
+ src_total += count_sr_conflicts (states[i]);
+ rrc_total += count_rr_conflicts (states[i], true);
}
+ }
- fprintf(foutput, " $default\treduce using rule %d (%s)\n\n",
- default_rule, tags[rlhs[default_rule]]);
- }
- else if (n - m >= 1)
- {
- cmax = 0;
- default_LA = -1;
- fp4 = lookaheadset + tokensetsize;
+ src_ok = src_total == (expected_conflicts == -1 ? 0 : expected_conflicts);
- if (! nodefault)
- for (i = m; i < n; i++)
- {
- fp1 = LA + i * tokensetsize;
- fp2 = shiftset;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
- *fp3++ = *fp1++ & ( ~ (*fp2++));
-
- count = 0;
- mask = 1;
- fp3 = lookaheadset;
- for (j = 0; j < ntokens; j++)
- {
- if (mask & *fp3)
- count++;
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp3++;
- }
- }
-
- if (count > cmax)
- {
- cmax = count;
- default_LA = i;
- default_rule = LAruleno[i];
- }
-
- fp2 = shiftset;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
- *fp2++ |= *fp3++;
- }
-
- for (i = 0; i < tokensetsize; i++)
- shiftset[i] = 0;
-
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(shiftset, symbol);
- }
- }
-
- mask = 1;
- fp1 = LA + m * tokensetsize;
- fp2 = shiftset;
- for (i = 0; i < ntokens; i++)
- {
- int defaulted = 0;
-
- if (mask & *fp2)
- count = 1;
- else
- count = 0;
-
- fp3 = fp1;
- for (j = m; j < n; j++)
- {
- if (mask & *fp3)
- {
- if (count == 0)
- {
- if (j != default_LA)
- {
- rule = LAruleno[j];
- fprintf(foutput, " %-4s\treduce using rule %d (%s)\n",
- tags[i], rule, tags[rlhs[rule]]);
- }
- else defaulted = 1;
-
- count++;
- }
- else
- {
- if (defaulted)
- {
- rule = LAruleno[default_LA];
- fprintf(foutput, " %-4s\treduce using rule %d (%s)\n",
- tags[i], rule, tags[rlhs[rule]]);
- defaulted = 0;
- }
- rule = LAruleno[j];
- fprintf(foutput, " %-4s\t[reduce using rule %d (%s)]\n",
- tags[i], rule, tags[rlhs[rule]]);
- }
- }
-
- fp3 += tokensetsize;
- }
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- /* This used to be fp1, but I think fp2 is right
- because fp2 is where the words are fetched to test with mask
- in this loop. */
- fp2++;
- }
- }
+ /* If there are no RR conflicts, and as many SR conflicts as
+ expected, then there is nothing to report. */
+ if (!rrc_total && src_ok)
+ return;
- if (default_LA >= 0)
- {
- fprintf(foutput, " $default\treduce using rule %d (%s)\n",
- default_rule, tags[rlhs[default_rule]]);
- }
+ /* Report the total number of conflicts on STDERR. */
+ if (yacc_flag)
+ conflict_report_yacc (src_total, rrc_total);
+ else
+ warn ("%s", conflict_report (src_total, rrc_total));
- putc('\n', foutput);
- }
+ if (expected_conflicts != -1 && !src_ok)
+ complain (ngettext ("expected %d shift/reduce conflict",
+ "expected %d shift/reduce conflicts",
+ expected_conflicts),
+ expected_conflicts);
}
void
-finalize_conflicts()
+conflicts_free (void)
{
- FREE(conflicts);
- FREE(shiftset);
- FREE(lookaheadset);
+ XFREE (conflicts);
+ bitset_free (shiftset);
+ bitset_free (lookaheadset);
+ obstack_free (&solved_conflicts_obstack, NULL);
}
projects / bison.git / blobdiff