X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/75ad86eebd3f49dff81976eb83036eb7b7793e68..dd31e17d7e415d3be8fc603f752f7e975297bcc2:/src/conflicts.c?ds=sidebyside diff --git a/src/conflicts.c b/src/conflicts.c index cb7f13a6..18c659da 100644 --- a/src/conflicts.c +++ b/src/conflicts.c @@ -1,24 +1,22 @@ /* Find and resolve or report lookahead conflicts for bison, - Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002, 2003, 2004, 2005, 2006, - 2007 Free Software Foundation, Inc. + Copyright (C) 1984, 1989, 1992, 2000-2012 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 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 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. - 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. + 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 <http://www.gnu.org/licenses/>. */ #include <config.h> #include "system.h" @@ -32,6 +30,7 @@ #include "getargs.h" #include "gram.h" #include "lalr.h" +#include "print-xml.h" #include "reader.h" #include "state.h" #include "symtab.h" @@ -41,6 +40,7 @@ int expected_sr_conflicts = -1; int expected_rr_conflicts = -1; static char *conflicts; static struct obstack solved_conflicts_obstack; +static struct obstack solved_conflicts_xml_obstack; static bitset shift_set; static bitset lookahead_set; @@ -64,81 +64,157 @@ enum conflict_resolution static inline void log_resolution (rule *r, symbol_number token, - enum conflict_resolution resolution) + enum conflict_resolution 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"), - r->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"), - r->number, - symbols[token]->tag); - break; - case nonassoc_resolution: - obstack_fgrow2 (&solved_conflicts_obstack, - _("\ - Conflict between rule %d and token %s resolved as an error"), - r->number, - symbols[token]->tag); - break; - } + { + case shift_resolution: + case right_resolution: + obstack_fgrow2 (&solved_conflicts_obstack, + _(" Conflict between rule %d and token %s" + " resolved as shift"), + r->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"), + r->number, + symbols[token]->tag); + break; + + case nonassoc_resolution: + obstack_fgrow2 (&solved_conflicts_obstack, + _(" Conflict between rule %d and token %s" + " resolved as an error"), + r->number, + symbols[token]->tag); + break; + } /* The reason. */ switch (resolution) - { - case shift_resolution: - obstack_fgrow2 (&solved_conflicts_obstack, - " (%s < %s)", - r->prec->tag, - symbols[token]->tag); - break; - - case reduce_resolution: - obstack_fgrow2 (&solved_conflicts_obstack, - " (%s < %s)", - symbols[token]->tag, - r->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; - } + { + case shift_resolution: + obstack_fgrow2 (&solved_conflicts_obstack, + " (%s < %s)", + r->prec->tag, + symbols[token]->tag); + break; + + case reduce_resolution: + obstack_fgrow2 (&solved_conflicts_obstack, + " (%s < %s)", + symbols[token]->tag, + r->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"); } + + /* XML report */ + if (xml_flag) + { + /* The description of the resolution. */ + switch (resolution) + { + case shift_resolution: + case right_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " <resolution rule=\"%d\" symbol=\"%s\"" + " type=\"shift\">", + r->number, + xml_escape (symbols[token]->tag)); + break; + + case reduce_resolution: + case left_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " <resolution rule=\"%d\" symbol=\"%s\"" + " type=\"reduce\">", + r->number, + xml_escape (symbols[token]->tag)); + break; + + case nonassoc_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " <resolution rule=\"%d\" symbol=\"%s\"" + " type=\"error\">", + r->number, + xml_escape (symbols[token]->tag)); + break; + } + + /* The reason. */ + switch (resolution) + { + case shift_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + "%s < %s", + xml_escape_n (0, r->prec->tag), + xml_escape_n (1, symbols[token]->tag)); + break; + + case reduce_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + "%s < %s", + xml_escape_n (0, symbols[token]->tag), + xml_escape_n (1, r->prec->tag)); + break; + + case left_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%left %s", + xml_escape (symbols[token]->tag)); + break; + + case right_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%right %s", + xml_escape (symbols[token]->tag)); + break; + + case nonassoc_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%nonassoc %s", + xml_escape (symbols[token]->tag)); + break; + } + + obstack_sgrow (&solved_conflicts_xml_obstack, "</resolution>\n"); + } } /*------------------------------------------------------------------. | 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. | +| favor of the reduction or as an error (%nonassoc). | `------------------------------------------------------------------*/ static void @@ -150,15 +226,15 @@ flush_shift (state *s, int token) bitset_reset (lookahead_set, token); for (i = 0; i < trans->num; i++) if (!TRANSITION_IS_DISABLED (trans, i) - && TRANSITION_SYMBOL (trans, i) == token) + && TRANSITION_SYMBOL (trans, i) == token) TRANSITION_DISABLE (trans, i); } /*--------------------------------------------------------------------. -| 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. | +| Turn off the reduce recorded for the specified token in the | +| specified lookahead set. Used when we resolve a shift-reduce | +| conflict in favor of the shift or as an error (%nonassoc). | `--------------------------------------------------------------------*/ static void @@ -176,11 +252,12 @@ flush_reduce (bitset lookahead_tokens, int token) | | | RULENO is the number of the lookahead bitset to consider. | | | -| ERRORS can be used to store discovered explicit errors. | +| ERRORS and NERRS can be used to store discovered explicit | +| errors. | `------------------------------------------------------------------*/ static void -resolve_sr_conflict (state *s, int ruleno, symbol **errors) +resolve_sr_conflict (state *s, int ruleno, symbol **errors, int *nerrs) { symbol_number i; reductions *reds = s->reductions; @@ -188,69 +265,60 @@ resolve_sr_conflict (state *s, int ruleno, symbol **errors) rule *redrule = reds->rules[ruleno]; int redprec = redrule->prec->prec; bitset lookahead_tokens = reds->lookahead_tokens[ruleno]; - int nerrs = 0; for (i = 0; i < ntokens; i++) if (bitset_test (lookahead_tokens, i) - && bitset_test (lookahead_set, i) - && symbols[i]->prec) + && bitset_test (lookahead_set, i) + && symbols[i]->prec) { - /* 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) - { - log_resolution (redrule, i, reduce_resolution); - flush_shift (s, i); - } - else if (symbols[i]->prec > redprec) - { - log_resolution (redrule, i, shift_resolution); - flush_reduce (lookahead_tokens, i); - } - else - /* Matching precedence levels. - For left association, keep only the reduction. - For right association, keep only the shift. - For nonassociation, keep neither. */ - - switch (symbols[i]->assoc) - { - default: - abort (); - - case right_assoc: - log_resolution (redrule, i, right_resolution); - flush_reduce (lookahead_tokens, i); - break; - - case left_assoc: - log_resolution (redrule, i, left_resolution); - flush_shift (s, i); - break; - - case non_assoc: - log_resolution (redrule, i, nonassoc_resolution); - flush_shift (s, i); - flush_reduce (lookahead_tokens, i); - /* Record an explicit error for this token. */ - errors[nerrs++] = symbols[i]; - break; - } + /* 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) + { + log_resolution (redrule, i, reduce_resolution); + flush_shift (s, i); + } + else if (symbols[i]->prec > redprec) + { + log_resolution (redrule, i, shift_resolution); + flush_reduce (lookahead_tokens, i); + } + else + /* Matching precedence levels. + For non-defined associativity, keep both: unexpected + associativity conflict. + For left associativity, keep only the reduction. + For right associativity, keep only the shift. + For nonassociativity, keep neither. */ + + switch (symbols[i]->assoc) + { + case undef_assoc: + abort (); + + case precedence_assoc: + break; + + case right_assoc: + log_resolution (redrule, i, right_resolution); + flush_reduce (lookahead_tokens, i); + break; + + case left_assoc: + log_resolution (redrule, i, left_resolution); + flush_shift (s, i); + break; + + case non_assoc: + log_resolution (redrule, i, nonassoc_resolution); + flush_shift (s, i); + flush_reduce (lookahead_tokens, i); + /* Record an explicit error for this token. */ + errors[(*nerrs)++] = symbols[i]; + break; + } } - - if (nerrs) - { - /* Some tokens have been explicitly made errors. Allocate a - permanent errs structure for this state, to record them. */ - state_errs_set (s, nerrs, errors); - } - - if (obstack_object_size (&solved_conflicts_obstack)) - { - obstack_1grow (&solved_conflicts_obstack, '\0'); - s->solved_conflicts = obstack_finish (&solved_conflicts_obstack); - } } @@ -267,6 +335,7 @@ set_conflicts (state *s, symbol **errors) int i; transitions *trans = s->transitions; reductions *reds = s->reductions; + int nerrs = 0; if (s->consistent) return; @@ -281,16 +350,32 @@ set_conflicts (state *s, symbol **errors) precedence. */ for (i = 0; i < reds->num; ++i) if (reds->rules[i]->prec && reds->rules[i]->prec->prec - && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set)) - resolve_sr_conflict (s, i, errors); + && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set)) + resolve_sr_conflict (s, i, errors, &nerrs); + + if (nerrs) + { + /* Some tokens have been explicitly made errors. Allocate a + permanent errs structure for this state, to record them. */ + state_errs_set (s, nerrs, errors); + } + if (obstack_object_size (&solved_conflicts_obstack)) + { + obstack_1grow (&solved_conflicts_obstack, '\0'); + s->solved_conflicts = obstack_finish (&solved_conflicts_obstack); + } + if (obstack_object_size (&solved_conflicts_xml_obstack)) + { + obstack_1grow (&solved_conflicts_xml_obstack, '\0'); + s->solved_conflicts_xml = obstack_finish (&solved_conflicts_xml_obstack); + } /* Loop over all rules which require lookahead in this state. Check for conflicts not resolved above. */ for (i = 0; i < reds->num; ++i) { if (!bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set)) - conflicts[s->number] = 1; - + conflicts[s->number] = 1; bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]); } } @@ -312,15 +397,16 @@ conflicts_solve (void) shift_set = bitset_create (ntokens, BITSET_FIXED); lookahead_set = bitset_create (ntokens, BITSET_FIXED); obstack_init (&solved_conflicts_obstack); + obstack_init (&solved_conflicts_xml_obstack); for (i = 0; i < nstates; i++) { set_conflicts (states[i], errors); /* For uniformity of the code, make sure all the states have a valid - `errs' member. */ + `errs' member. */ if (!states[i]->errs) - states[i]->errs = errs_new (0, 0); + states[i]->errs = errs_new (0, 0); } free (errors); @@ -331,7 +417,8 @@ void conflicts_update_state_numbers (state_number old_to_new[], state_number nstates_old) { - for (state_number i = 0; i < nstates_old; ++i) + state_number i; + for (i = 0; i < nstates_old; ++i) if (old_to_new[i] != nstates_old) conflicts[old_to_new[i]] = conflicts[i]; } @@ -388,11 +475,11 @@ count_rr_conflicts (state *s, bool one_per_token) int count = 0; int j; for (j = 0; j < reds->num; ++j) - if (bitset_test (reds->lookahead_tokens[j], i)) - count++; + if (bitset_test (reds->lookahead_tokens[j], i)) + count++; if (count >= 2) - rrc_count += one_per_token ? 1 : count-1; + rrc_count += one_per_token ? 1 : count-1; } return rrc_count; @@ -408,7 +495,7 @@ conflict_report (FILE *out, int src_num, int rrc_num) { if (src_num && rrc_num) fprintf (out, _("conflicts: %d shift/reduce, %d reduce/reduce\n"), - src_num, rrc_num); + src_num, rrc_num); else if (src_num) fprintf (out, _("conflicts: %d shift/reduce\n"), src_num); else if (rrc_num) @@ -429,12 +516,12 @@ conflicts_output (FILE *out) { state *s = states[i]; if (conflicts[i]) - { - fprintf (out, _("State %d "), i); - conflict_report (out, count_sr_conflicts (s), - count_rr_conflicts (s, true)); - printed_sth = true; - } + { + fprintf (out, _("State %d "), i); + conflict_report (out, count_sr_conflicts (s), + count_rr_conflicts (s, true)); + printed_sth = true; + } } if (printed_sth) fputs ("\n\n", out); @@ -444,7 +531,7 @@ conflicts_output (FILE *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. | +| conflict. | `--------------------------------------------------------*/ int @@ -458,8 +545,8 @@ conflicts_total_count (void) for (i = 0; i < nstates; i++) if (conflicts[i]) { - count += count_sr_conflicts (states[i]); - count += count_rr_conflicts (states[i], false); + count += count_sr_conflicts (states[i]); + count += count_rr_conflicts (states[i], false); } return count; } @@ -489,10 +576,10 @@ conflicts_print (void) for (i = 0; i < nstates; i++) if (conflicts[i]) - { - src_total += count_sr_conflicts (states[i]); - rrc_total += count_rr_conflicts (states[i], true); - } + { + src_total += count_sr_conflicts (states[i]); + rrc_total += count_rr_conflicts (states[i], true); + } } if (! glr_parser && rrc_total > 0 && expected_rr_conflicts != -1) @@ -512,25 +599,34 @@ conflicts_print (void) return; /* Report the total number of conflicts on STDERR. */ + if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1) + { + if (!(warnings_flag & warnings_conflicts_sr)) + src_total = 0; + if (!(warnings_flag & warnings_conflicts_rr)) + rrc_total = 0; + } if (src_total | rrc_total) { + if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1) + set_warning_issued (); if (! yacc_flag) - fprintf (stderr, "%s: ", current_file); + fprintf (stderr, "%s: ", current_file); conflict_report (stderr, src_total, rrc_total); } if (expected_sr_conflicts != -1 || expected_rr_conflicts != -1) { if (! src_ok) - complain (ngettext ("expected %d shift/reduce conflict", - "expected %d shift/reduce conflicts", - src_expected), - src_expected); + complain (ngettext ("expected %d shift/reduce conflict", + "expected %d shift/reduce conflicts", + src_expected), + src_expected); if (! rrc_ok) - complain (ngettext ("expected %d reduce/reduce conflict", - "expected %d reduce/reduce conflicts", - rrc_expected), - rrc_expected); + complain (ngettext ("expected %d reduce/reduce conflict", + "expected %d reduce/reduce conflicts", + rrc_expected), + rrc_expected); } } @@ -542,4 +638,5 @@ conflicts_free (void) bitset_free (shift_set); bitset_free (lookahead_set); obstack_free (&solved_conflicts_obstack, NULL); + obstack_free (&solved_conflicts_xml_obstack, NULL); }