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reduced by a state, attach the lookaheads to the reductions. * src/state.h (state_t): Remove the `lookaheads', `lookaheads_rule' member. (reductions_t): Add a `lookaheads' member. Use a regular array for the `rules'. * src/state.c (reductions_new): Initialize the lookaheads member to 0. (state_rule_lookaheads_print): Adjust. * src/state.h, src/state.c (state_reductions_find): New. * src/conflicts.c (resolve_sr_conflict, set_conflicts) (count_rr_conflicts): Adjust. * src/lalr.c (LArule): Remove. (add_lookback_edge): Adjust. (state_lookaheads_count): New. (states_lookaheads_initialize): Merge into... (initialize_LA): this. (lalr_free): Adjust. * src/main.c (main): Don't free nullable and derives too early: it is used by --verbose. * src/print.c, src/print_graph.c, src/tables.c: Adjust.
915 lines
25 KiB
C
915 lines
25 KiB
C
/* Output the generated parsing program for bison,
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Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002
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Free Software Foundation, Inc.
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This file is part of Bison, the GNU Compiler Compiler.
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Bison is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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Bison is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Bison; see the file COPYING. If not, write to the Free
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Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
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02111-1307, USA. */
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/* The parser tables consist of these tables.
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YYTRANSLATE = vector mapping yylex's token numbers into bison's
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token numbers.
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YYTNAME = vector of string-names indexed by bison token number.
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YYTOKNUM = vector of yylex token numbers corresponding to entries
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in YYTNAME.
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YYRLINE = vector of line-numbers of all rules. For yydebug
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printouts.
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YYRHS = vector of items of all rules. This is exactly what RITEMS
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contains. For yydebug and for semantic parser.
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YYPRHS[R] = index in YYRHS of first item for rule R.
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YYR1[R] = symbol number of symbol that rule R derives.
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YYR2[R] = number of symbols composing right hand side of rule R.
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YYSTOS[S] = the symbol number of the symbol that leads to state S.
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YYDEFACT[S] = default rule to reduce with in state s, when YYTABLE
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doesn't specify something else to do. Zero means the default is an
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error.
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YYDEFGOTO[I] = default state to go to after a reduction of a rule
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that generates variable NTOKENS + I, except when YYTABLE specifies
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something else to do.
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YYPACT[S] = index in YYTABLE of the portion describing state S.
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The lookahead token's type is used to index that portion to find
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out what to do.
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If the value in YYTABLE is positive, we shift the token and go to
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that state.
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If the value is negative, it is minus a rule number to reduce by.
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If the value is zero, the default action from YYDEFACT[S] is used.
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YYPGOTO[I] = the index in YYTABLE of the portion describing what to
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do after reducing a rule that derives variable I + NTOKENS. This
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portion is indexed by the parser state number, S, as of before the
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text for this nonterminal was read. The value from YYTABLE is the
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state to go to if the corresponding value in YYCHECK is S.
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YYTABLE = a vector filled with portions for different uses, found
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via YYPACT and YYPGOTO.
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YYCHECK = a vector indexed in parallel with YYTABLE. It indicates,
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in a roundabout way, the bounds of the portion you are trying to
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examine.
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Suppose that the portion of YYTABLE starts at index P and the index
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to be examined within the portion is I. Then if YYCHECK[P+I] != I,
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I is outside the bounds of what is actually allocated, and the
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default (from YYDEFACT or YYDEFGOTO) should be used. Otherwise,
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YYTABLE[P+I] should be used.
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YYFINAL = the state number of the termination state. YYFLAG = most
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negative short int. Used to flag ?? */
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#include "system.h"
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#include "bitsetv.h"
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#include "quotearg.h"
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#include "getargs.h"
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#include "files.h"
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#include "gram.h"
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#include "complain.h"
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#include "lalr.h"
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#include "reader.h"
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#include "symtab.h"
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#include "conflicts.h"
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#include "tables.h"
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/* Several tables will be indexed both by state and nonterminal
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numbers. We call `vector' such a thing (= either a state or a
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symbol number.
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Of course vector_number_t ought to be wide enough to contain
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state_number_t and symbol_number_t. */
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typedef short vector_number_t;
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#define VECTOR_NUMBER_MAX ((vector_number_t) SHRT_MAX)
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#define VECTOR_NUMBER_MIN ((vector_number_t) SHRT_MIN)
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#define state_number_to_vector_number(State) \
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((vector_number_t) State)
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#define symbol_number_to_vector_number(Symbol) \
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((vector_number_t) (state_number_as_int (nstates) + Symbol - ntokens))
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int nvectors;
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/* FROMS and TOS are indexed by vector_number_t.
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If VECTOR is a nonterminal, (FROMS[VECTOR], TOS[VECTOR]) form an
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array of state numbers of the non defaulted GOTO on VECTOR.
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If VECTOR is a state, TOS[VECTOR] is the array of actions to do on
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the (array of) symbols FROMS[VECTOR].
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In both cases, TALLY[VECTOR] is the size of the arrays
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FROMS[VECTOR], TOS[VECTOR]; and WIDTH[VECTOR] =
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(FROMS[VECTOR][SIZE] - FROMS[VECTOR][0] + 1) where SIZE =
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TALLY[VECTOR].
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FROMS therefore contains symbol_number_t and action_number_t,
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TOS state_number_t and action_number_t,
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TALLY sizes,
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WIDTH differences of FROMS.
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Let base_t be the type of FROMS, TOS, and WIDTH. */
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#define BASE_MAX ((base_t) INT_MAX)
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#define BASE_MIN ((base_t) INT_MIN)
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static base_t **froms = NULL;
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static base_t **tos = NULL;
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static unsigned int **conflict_tos = NULL;
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static short *tally = NULL;
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static base_t *width = NULL;
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/* For a given state, N = ACTROW[SYMBOL]:
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If N = 0, stands for `run the default action'.
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If N = MIN, stands for `raise a parse error'.
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If N > 0, stands for `shift SYMBOL and go to n'.
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If N < 0, stands for `reduce -N'. */
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typedef short action_t;
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#define ACTION_MAX ((action_t) SHRT_MAX)
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#define ACTION_MIN ((action_t) SHRT_MIN)
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static action_t *actrow = NULL;
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/* FROMS and TOS are reordered to be compressed. ORDER[VECTOR] is the
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new vector number of VECTOR. We skip `empty' vectors (i.e.,
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TALLY[VECTOR] = 0), and call these `entries'. */
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static vector_number_t *order = NULL;
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static int nentries;
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base_t *base = NULL;
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/* A distinguished value of BASE, negative infinite. During the
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computation equals to BASE_MIN, later mapped to BASE_NINF to
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keep parser tables small. */
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base_t base_ninf = 0;
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static base_t *pos = NULL;
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static unsigned int *conflrow = NULL;
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unsigned int *conflict_table = NULL;
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unsigned int *conflict_list = NULL;
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int conflict_list_cnt;
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static int conflict_list_free;
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/* TABLE_SIZE is the allocated size of both TABLE and CHECK. We start
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with more or less the original hard-coded value (which was
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SHRT_MAX). */
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static size_t table_size = 32768;
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base_t *table = NULL;
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base_t *check = NULL;
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/* The value used in TABLE to denote explicit parse errors
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(%nonassoc), a negative infinite. First defaults to ACTION_MIN,
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but in order to keep small tables, renumbered as TABLE_ERROR, which
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is the smallest (non error) value minus 1. */
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base_t table_ninf = 0;
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static int lowzero;
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int high;
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state_number_t *yydefgoto;
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rule_number_t *yydefact;
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/*----------------------------------------------------------------.
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| If TABLE (and CHECK) appear to be small to be addressed at |
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| DESIRED, grow them. Note that TABLE[DESIRED] is to be used, so |
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| the desired size is at least DESIRED + 1. |
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`----------------------------------------------------------------*/
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static void
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table_grow (size_t desired)
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{
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size_t old_size = table_size;
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while (table_size <= desired)
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table_size *= 2;
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if (trace_flag & trace_resource)
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fprintf (stderr, "growing table and check from: %d to %d\n",
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old_size, table_size);
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table = XREALLOC (table, base_t, table_size);
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check = XREALLOC (check, base_t, table_size);
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if (glr_parser)
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conflict_table = XREALLOC (conflict_table, unsigned int, table_size);
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for (/* Nothing. */; old_size < table_size; ++old_size)
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{
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table[old_size] = 0;
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check[old_size] = -1;
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}
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}
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/*-------------------------------------------------------------------.
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| For GLR parsers, for each conflicted token in STATE, as indicated |
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| by non-zero entries in CONFLROW, create a list of possible |
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| reductions that are alternatives to the shift or reduction |
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| currently recorded for that token in STATE. Store the alternative |
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| reductions followed by a 0 in CONFLICT_LIST, updating |
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| CONFLICT_LIST_CNT, and storing an index to the start of the list |
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| back into CONFLROW. |
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`-------------------------------------------------------------------*/
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static void
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conflict_row (state_t *state)
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{
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int i, j;
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reductions_t *reds = state->reductions;
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if (! glr_parser)
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return;
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for (j = 0; j < ntokens; j += 1)
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if (conflrow[j])
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{
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conflrow[j] = conflict_list_cnt;
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/* Find all reductions for token J, and record all that do not
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match ACTROW[J]. */
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for (i = 0; i < reds->num; i += 1)
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if (bitset_test (reds->lookaheads[i], j)
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&& (actrow[j]
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!= rule_number_as_item_number (reds->rules[i]->number)))
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{
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assert (conflict_list_free > 0);
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conflict_list[conflict_list_cnt] = reds->rules[i]->number + 1;
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conflict_list_cnt += 1;
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conflict_list_free -= 1;
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}
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/* Leave a 0 at the end. */
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assert (conflict_list_free > 0);
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conflict_list_cnt += 1;
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conflict_list_free -= 1;
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}
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}
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/*------------------------------------------------------------------.
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| Decide what to do for each type of token if seen as the lookahead |
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| token in specified state. The value returned is used as the |
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| default action (yydefact) for the state. In addition, ACTROW is |
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| filled with what to do for each kind of token, index by symbol |
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| number, with zero meaning do the default action. The value |
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| ACTION_MIN, a very negative number, means this situation is an |
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| error. The parser recognizes this value specially. |
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| |
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| This is where conflicts are resolved. The loop over lookahead |
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| rules considered lower-numbered rules last, and the last rule |
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| considered that likes a token gets to handle it. |
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| |
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| For GLR parsers, also sets CONFLROW[SYM] to an index into |
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| CONFLICT_LIST iff there is an unresolved conflict (s/r or r/r) |
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| with symbol SYM. The default reduction is not used for a symbol |
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| that has any such conflicts. |
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`------------------------------------------------------------------*/
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static rule_t *
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action_row (state_t *state)
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{
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int i;
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rule_t *default_rule = NULL;
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reductions_t *redp = state->reductions;
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transitions_t *transitions = state->transitions;
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errs_t *errp = state->errs;
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/* Set to nonzero to inhibit having any default reduction. */
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int nodefault = 0;
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int conflicted = 0;
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for (i = 0; i < ntokens; i++)
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actrow[i] = conflrow[i] = 0;
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if (redp->lookaheads)
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{
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int j;
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bitset_iterator biter;
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/* loop over all the rules available here which require
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lookahead (in reverse order to give precedence to the first
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rule) */
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for (i = redp->num - 1; i >= 0; --i)
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/* and find each token which the rule finds acceptable
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to come next */
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BITSET_FOR_EACH (biter, redp->lookaheads[i], j, 0)
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{
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/* and record this rule as the rule to use if that
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token follows. */
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if (actrow[j] != 0)
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conflicted = conflrow[j] = 1;
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actrow[j] = rule_number_as_item_number (redp->rules[i]->number);
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}
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}
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/* Now see which tokens are allowed for shifts in this state. For
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them, record the shift as the thing to do. So shift is preferred
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to reduce. */
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FOR_EACH_SHIFT (transitions, i)
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{
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symbol_number_t symbol = TRANSITION_SYMBOL (transitions, i);
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state_t *shift_state = transitions->states[i];
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if (actrow[symbol] != 0)
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conflicted = conflrow[symbol] = 1;
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actrow[symbol] = state_number_as_int (shift_state->number);
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/* Do not use any default reduction if there is a shift for
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error */
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if (symbol == errtoken->number)
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nodefault = 1;
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}
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/* See which tokens are an explicit error in this state (due to
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%nonassoc). For them, record ACTION_MIN as the action. */
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for (i = 0; i < errp->num; i++)
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{
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symbol_t *symbol = errp->symbols[i];
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actrow[symbol->number] = ACTION_MIN;
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}
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/* Now find the most common reduction and make it the default action
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for this state. */
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if (redp->num >= 1 && !nodefault)
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{
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if (state->consistent)
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default_rule = redp->rules[0];
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else
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{
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int max = 0;
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for (i = 0; i < redp->num; i++)
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{
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int count = 0;
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rule_t *rule = redp->rules[i];
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symbol_number_t j;
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for (j = 0; j < ntokens; j++)
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if (actrow[j] == rule_number_as_item_number (rule->number))
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count++;
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if (count > max)
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{
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max = count;
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default_rule = rule;
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}
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}
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/* GLR parsers need space for conflict lists, so we can't
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default conflicted entries. For non-conflicted entries
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or as long as we are not building a GLR parser,
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actions that match the default are replaced with zero,
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which means "use the default". */
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if (max > 0)
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{
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int j;
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for (j = 0; j < ntokens; j++)
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if (actrow[j] == rule_number_as_item_number (default_rule->number)
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&& ! (glr_parser && conflrow[j]))
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actrow[j] = 0;
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}
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}
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}
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/* Find the rules which are reduced. */
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if (!glr_parser)
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{
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for (i = 0; i < ntokens; i++)
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if (actrow[i] < 0 && actrow[i] != ACTION_MIN)
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rules[item_number_as_rule_number (actrow[i])].useful = TRUE;
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if (default_rule)
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default_rule->useful = TRUE;
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}
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/* If have no default rule, the default is an error.
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So replace any action which says "error" with "use default". */
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if (!default_rule)
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for (i = 0; i < ntokens; i++)
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if (actrow[i] == ACTION_MIN)
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actrow[i] = 0;
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if (conflicted)
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conflict_row (state);
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return default_rule;
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}
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/*--------------------------------------------.
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| Set FROMS, TOS, TALLY and WIDTH for STATE. |
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`--------------------------------------------*/
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static void
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save_row (state_number_t state)
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{
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symbol_number_t i;
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int count;
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base_t *sp = NULL;
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base_t *sp1 = NULL;
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base_t *sp2 = NULL;
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unsigned int *sp3 = NULL;
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/* Number of non default actions in STATE. */
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count = 0;
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for (i = 0; i < ntokens; i++)
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if (actrow[i] != 0)
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count++;
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if (count == 0)
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return;
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/* Allocate non defaulted actions. */
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froms[state] = sp1 = sp = XCALLOC (base_t, count);
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tos[state] = sp2 = XCALLOC (base_t, count);
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if (glr_parser)
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conflict_tos[state] = sp3 = XCALLOC (unsigned int, count);
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else
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conflict_tos[state] = NULL;
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/* Store non defaulted actions. */
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for (i = 0; i < ntokens; i++)
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if (actrow[i] != 0)
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{
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*sp1++ = i;
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*sp2++ = actrow[i];
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if (glr_parser)
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*sp3++ = conflrow[i];
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}
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tally[state] = count;
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width[state] = sp1[-1] - sp[0] + 1;
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}
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/*------------------------------------------------------------------.
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| Figure out the actions for the specified state, indexed by |
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| lookahead token type. |
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| |
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| The YYDEFACT table is output now. The detailed info is saved for |
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| putting into YYTABLE later. |
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`------------------------------------------------------------------*/
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static void
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token_actions (void)
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{
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state_number_t i;
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rule_number_t r;
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int nconflict = conflicts_total_count ();
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yydefact = XCALLOC (rule_number_t, nstates);
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actrow = XCALLOC (action_t, ntokens);
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conflrow = XCALLOC (unsigned int, ntokens);
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/* Now that the parser was computed, we can find which rules are
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really reduced, and which are not because of SR or RR conflicts.
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*/
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if (!glr_parser)
|
||
for (r = 0; r < nrules; ++r)
|
||
rules[r].useful = FALSE;
|
||
|
||
if (glr_parser)
|
||
{
|
||
conflict_list = XCALLOC (unsigned int, 1 + 2 * nconflict);
|
||
conflict_list_free = 2 * nconflict;
|
||
conflict_list_cnt = 1;
|
||
}
|
||
else
|
||
conflict_list_free = conflict_list_cnt = 0;
|
||
|
||
for (i = 0; i < nstates; ++i)
|
||
{
|
||
rule_t *default_rule = action_row (states[i]);
|
||
yydefact[i] = default_rule ? default_rule->number + 1 : 0;
|
||
save_row (i);
|
||
}
|
||
|
||
if (!glr_parser)
|
||
for (r = 0; r < nrules ; ++r)
|
||
if (!rules[r].useful)
|
||
{
|
||
LOCATION_PRINT (stderr, rules[r].location);
|
||
fprintf (stderr, ": %s: %s: ",
|
||
_("warning"), _("rule never reduced because of conflicts"));
|
||
rule_print (&rules[r], stderr);
|
||
}
|
||
|
||
free (actrow);
|
||
free (conflrow);
|
||
}
|
||
|
||
|
||
/*------------------------------------------------------------------.
|
||
| Compute FROMS[VECTOR], TOS[VECTOR], TALLY[VECTOR], WIDTH[VECTOR], |
|
||
| i.e., the information related to non defaulted GOTO on the nterm |
|
||
| SYMBOL. |
|
||
| |
|
||
| DEFAULT_STATE is the principal destination on SYMBOL, i.e., the |
|
||
| default GOTO destination on SYMBOL. |
|
||
`------------------------------------------------------------------*/
|
||
|
||
static void
|
||
save_column (symbol_number_t symbol, state_number_t default_state)
|
||
{
|
||
int i;
|
||
base_t *sp;
|
||
base_t *sp1;
|
||
base_t *sp2;
|
||
int count;
|
||
vector_number_t symno = symbol_number_to_vector_number (symbol);
|
||
|
||
goto_number_t begin = goto_map[symbol];
|
||
goto_number_t end = goto_map[symbol + 1];
|
||
|
||
/* Number of non default GOTO. */
|
||
count = 0;
|
||
for (i = begin; i < end; i++)
|
||
if (to_state[i] != default_state)
|
||
count++;
|
||
|
||
if (count == 0)
|
||
return;
|
||
|
||
/* Allocate room for non defaulted gotos. */
|
||
froms[symno] = sp1 = sp = XCALLOC (base_t, count);
|
||
tos[symno] = sp2 = XCALLOC (base_t, count);
|
||
|
||
/* Store the state numbers of the non defaulted gotos. */
|
||
for (i = begin; i < end; i++)
|
||
if (to_state[i] != default_state)
|
||
{
|
||
*sp1++ = from_state[i];
|
||
*sp2++ = to_state[i];
|
||
}
|
||
|
||
tally[symno] = count;
|
||
width[symno] = sp1[-1] - sp[0] + 1;
|
||
}
|
||
|
||
|
||
/*----------------------------------------------------------------.
|
||
| Return `the' most common destination GOTO on SYMBOL (a nterm). |
|
||
`----------------------------------------------------------------*/
|
||
|
||
static state_number_t
|
||
default_goto (symbol_number_t symbol, short state_count[])
|
||
{
|
||
state_number_t s;
|
||
int i;
|
||
goto_number_t m = goto_map[symbol];
|
||
goto_number_t n = goto_map[symbol + 1];
|
||
state_number_t default_state = (state_number_t) -1;
|
||
int max = 0;
|
||
|
||
if (m == n)
|
||
return (state_number_t) -1;
|
||
|
||
for (s = 0; s < nstates; s++)
|
||
state_count[s] = 0;
|
||
|
||
for (i = m; i < n; i++)
|
||
state_count[to_state[i]]++;
|
||
|
||
for (s = 0; s < nstates; s++)
|
||
if (state_count[s] > max)
|
||
{
|
||
max = state_count[s];
|
||
default_state = s;
|
||
}
|
||
|
||
return default_state;
|
||
}
|
||
|
||
|
||
/*-------------------------------------------------------------------.
|
||
| Figure out what to do after reducing with each rule, depending on |
|
||
| the saved state from before the beginning of parsing the data that |
|
||
| matched this rule. |
|
||
| |
|
||
| The YYDEFGOTO table is output now. The detailed info is saved for |
|
||
| putting into YYTABLE later. |
|
||
`-------------------------------------------------------------------*/
|
||
|
||
static void
|
||
goto_actions (void)
|
||
{
|
||
symbol_number_t i;
|
||
short *state_count = XCALLOC (short, nstates);
|
||
yydefgoto = XMALLOC (state_number_t, nvars);
|
||
|
||
/* For a given nterm I, STATE_COUNT[S] is the number of times there
|
||
is a GOTO to S on I. */
|
||
for (i = ntokens; i < nsyms; ++i)
|
||
{
|
||
state_number_t default_state = default_goto (i, state_count);
|
||
save_column (i, default_state);
|
||
yydefgoto[i - ntokens] = default_state;
|
||
}
|
||
free (state_count);
|
||
}
|
||
|
||
|
||
/*------------------------------------------------------------------.
|
||
| Compute ORDER, a reordering of vectors, in order to decide how to |
|
||
| pack the actions and gotos information into yytable. |
|
||
`------------------------------------------------------------------*/
|
||
|
||
static void
|
||
sort_actions (void)
|
||
{
|
||
int i;
|
||
|
||
nentries = 0;
|
||
|
||
for (i = 0; i < nvectors; i++)
|
||
if (tally[i] > 0)
|
||
{
|
||
int k;
|
||
int t = tally[i];
|
||
int w = width[i];
|
||
int j = nentries - 1;
|
||
|
||
while (j >= 0 && (width[order[j]] < w))
|
||
j--;
|
||
|
||
while (j >= 0 && (width[order[j]] == w) && (tally[order[j]] < t))
|
||
j--;
|
||
|
||
for (k = nentries - 1; k > j; k--)
|
||
order[k + 1] = order[k];
|
||
|
||
order[j + 1] = i;
|
||
nentries++;
|
||
}
|
||
}
|
||
|
||
|
||
/* If VECTOR is a state which actions (reflected by FROMS, TOS, TALLY
|
||
and WIDTH of VECTOR) are common to a previous state, return this
|
||
state number.
|
||
|
||
In any other case, return -1. */
|
||
|
||
static state_number_t
|
||
matching_state (vector_number_t vector)
|
||
{
|
||
vector_number_t i = order[vector];
|
||
int t;
|
||
int w;
|
||
int prev;
|
||
|
||
/* If VECTOR is a nterm, return -1. */
|
||
if (i >= (int) nstates)
|
||
return -1;
|
||
|
||
t = tally[i];
|
||
w = width[i];
|
||
|
||
for (prev = vector - 1; prev >= 0; prev--)
|
||
{
|
||
vector_number_t j = order[prev];
|
||
int k;
|
||
int match = 1;
|
||
|
||
/* Given how ORDER was computed, if the WIDTH or TALLY is
|
||
different, there cannot be a matching state. */
|
||
if (width[j] != w || tally[j] != t)
|
||
return -1;
|
||
|
||
for (k = 0; match && k < t; k++)
|
||
if (tos[j][k] != tos[i][k] || froms[j][k] != froms[i][k])
|
||
match = 0;
|
||
|
||
if (match)
|
||
return j;
|
||
}
|
||
|
||
return -1;
|
||
}
|
||
|
||
|
||
static base_t
|
||
pack_vector (vector_number_t vector)
|
||
{
|
||
vector_number_t i = order[vector];
|
||
int j;
|
||
int t = tally[i];
|
||
int loc = 0;
|
||
base_t *from = froms[i];
|
||
base_t *to = tos[i];
|
||
unsigned int *conflict_to = conflict_tos[i];
|
||
|
||
assert (t);
|
||
|
||
for (j = lowzero - from[0]; j < (int) table_size; j++)
|
||
{
|
||
int k;
|
||
int ok = 1;
|
||
|
||
for (k = 0; ok && k < t; k++)
|
||
{
|
||
loc = j + state_number_as_int (from[k]);
|
||
if (loc >= (int) table_size)
|
||
table_grow (loc);
|
||
|
||
if (table[loc] != 0)
|
||
ok = 0;
|
||
}
|
||
|
||
for (k = 0; ok && k < vector; k++)
|
||
if (pos[k] == j)
|
||
ok = 0;
|
||
|
||
if (ok)
|
||
{
|
||
for (k = 0; k < t; k++)
|
||
{
|
||
loc = j + from[k];
|
||
table[loc] = to[k];
|
||
if (glr_parser && conflict_to != NULL)
|
||
conflict_table[loc] = conflict_to[k];
|
||
check[loc] = from[k];
|
||
}
|
||
|
||
while (table[lowzero] != 0)
|
||
lowzero++;
|
||
|
||
if (loc > high)
|
||
high = loc;
|
||
|
||
if (j < BASE_MIN || BASE_MAX < j)
|
||
fatal ("base_t too small to hold %d\n", j);
|
||
return j;
|
||
}
|
||
}
|
||
#define pack_vector_succeeded 0
|
||
assert (pack_vector_succeeded);
|
||
return 0;
|
||
}
|
||
|
||
|
||
/*-------------------------------------------------------------.
|
||
| Remap the negative infinite in TAB from NINF to the greatest |
|
||
| possible smallest value. Return it. |
|
||
| |
|
||
| In most case this allows us to use shorts instead of ints in |
|
||
| parsers. |
|
||
`-------------------------------------------------------------*/
|
||
|
||
static base_t
|
||
table_ninf_remap (base_t tab[], size_t size, base_t ninf)
|
||
{
|
||
base_t res = 0;
|
||
size_t i;
|
||
|
||
for (i = 0; i < size; i++)
|
||
if (tab[i] < res && tab[i] != ninf)
|
||
res = base[i];
|
||
|
||
--res;
|
||
|
||
for (i = 0; i < size; i++)
|
||
if (tab[i] == ninf)
|
||
tab[i] = res;
|
||
|
||
return res;
|
||
}
|
||
|
||
static void
|
||
pack_table (void)
|
||
{
|
||
int i;
|
||
|
||
base = XCALLOC (base_t, nvectors);
|
||
pos = XCALLOC (base_t, nentries);
|
||
table = XCALLOC (base_t, table_size);
|
||
if (glr_parser)
|
||
conflict_table = XCALLOC (unsigned int, table_size);
|
||
check = XCALLOC (base_t, table_size);
|
||
|
||
lowzero = 0;
|
||
high = 0;
|
||
|
||
for (i = 0; i < nvectors; i++)
|
||
base[i] = BASE_MIN;
|
||
|
||
for (i = 0; i < (int) table_size; i++)
|
||
check[i] = -1;
|
||
|
||
for (i = 0; i < nentries; i++)
|
||
{
|
||
state_number_t state = matching_state (i);
|
||
base_t place;
|
||
|
||
if (state < 0)
|
||
/* A new set of state actions, or a nonterminal. */
|
||
place = pack_vector (i);
|
||
else
|
||
/* Action of I were already coded for STATE. */
|
||
place = base[state];
|
||
|
||
pos[i] = place;
|
||
base[order[i]] = place;
|
||
}
|
||
|
||
/* Use the greatest possible negative infinites. */
|
||
base_ninf = table_ninf_remap (base, nvectors, BASE_MIN);
|
||
table_ninf = table_ninf_remap (table, high + 1, ACTION_MIN);
|
||
|
||
free (pos);
|
||
}
|
||
|
||
|
||
|
||
/*-----------------------------------------------------------------.
|
||
| Compute and output yydefact, yydefgoto, yypact, yypgoto, yytable |
|
||
| and yycheck. |
|
||
`-----------------------------------------------------------------*/
|
||
|
||
void
|
||
tables_generate (void)
|
||
{
|
||
int i;
|
||
|
||
/* That's a poor way to make sure the sizes are properly corelated,
|
||
in particular the signedness is not taking into account, but it's
|
||
not useless. */
|
||
assert (sizeof (nvectors) >= sizeof (nstates));
|
||
assert (sizeof (nvectors) >= sizeof (nvars));
|
||
|
||
nvectors = state_number_as_int (nstates) + nvars;
|
||
|
||
froms = XCALLOC (base_t *, nvectors);
|
||
tos = XCALLOC (base_t *, nvectors);
|
||
conflict_tos = XCALLOC (unsigned int *, nvectors);
|
||
tally = XCALLOC (short, nvectors);
|
||
width = XCALLOC (base_t, nvectors);
|
||
|
||
token_actions ();
|
||
|
||
goto_actions ();
|
||
XFREE (goto_map + ntokens);
|
||
XFREE (from_state);
|
||
XFREE (to_state);
|
||
|
||
order = XCALLOC (vector_number_t, nvectors);
|
||
sort_actions ();
|
||
pack_table ();
|
||
free (order);
|
||
|
||
free (tally);
|
||
free (width);
|
||
|
||
for (i = 0; i < nvectors; i++)
|
||
{
|
||
XFREE (froms[i]);
|
||
XFREE (tos[i]);
|
||
XFREE (conflict_tos[i]);
|
||
}
|
||
|
||
free (froms);
|
||
free (tos);
|
||
free (conflict_tos);
|
||
}
|
||
|
||
|
||
/*-------------------------.
|
||
| Free the parser tables. |
|
||
`-------------------------*/
|
||
|
||
void
|
||
tables_free (void)
|
||
{
|
||
free (base);
|
||
free (conflict_table);
|
||
free (conflict_list);
|
||
free (table);
|
||
free (check);
|
||
free (yydefgoto);
|
||
free (yydefact);
|
||
}
|