| 1 | /* Prepare the LALR and GLR parser tables. |
| 2 | |
| 3 | Copyright (C) 2002, 2004, 2009-2012 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of Bison, the GNU Compiler Compiler. |
| 6 | |
| 7 | This program is free software: you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation, either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #ifndef TABLES_H_ |
| 21 | # define TABLES_H_ |
| 22 | |
| 23 | # include "state.h" |
| 24 | |
| 25 | /* The parser tables consist of these tables. |
| 26 | |
| 27 | YYTRANSLATE = vector mapping yylex's token numbers into bison's |
| 28 | token numbers. |
| 29 | |
| 30 | YYTNAME = vector of string-names indexed by bison token number. |
| 31 | |
| 32 | YYTOKNUM = vector of yylex token numbers corresponding to entries |
| 33 | in YYTNAME. |
| 34 | |
| 35 | YYRLINE = vector of line-numbers of all rules. For yydebug |
| 36 | printouts. |
| 37 | |
| 38 | YYRHS = vector of items of all rules. This is exactly what RITEMS |
| 39 | contains. For yydebug and for semantic parser. |
| 40 | |
| 41 | YYPRHS[R] = index in YYRHS of first item for rule R. |
| 42 | |
| 43 | YYR1[R] = symbol number of symbol that rule R derives. |
| 44 | |
| 45 | YYR2[R] = number of symbols composing right hand side of rule R. |
| 46 | |
| 47 | YYSTOS[S] = the symbol number of the symbol that leads to state S. |
| 48 | |
| 49 | YYFINAL = the state number of the termination state. |
| 50 | |
| 51 | YYTABLE = a vector filled with portions for different uses, found |
| 52 | via YYPACT and YYPGOTO, described below. |
| 53 | |
| 54 | YYLAST ( = high) the number of the last element of YYTABLE, i.e., |
| 55 | sizeof (YYTABLE) - 1. |
| 56 | |
| 57 | YYCHECK = a vector indexed in parallel with YYTABLE. It indicates, |
| 58 | in a roundabout way, the bounds of the portion you are trying to |
| 59 | examine. |
| 60 | |
| 61 | Suppose that the portion of YYTABLE starts at index P and the index |
| 62 | to be examined within the portion is I. Then if YYCHECK[P+I] != I, |
| 63 | I is outside the bounds of what is actually allocated, and the |
| 64 | default (from YYDEFACT or YYDEFGOTO) should be used. Otherwise, |
| 65 | YYTABLE[P+I] should be used. |
| 66 | |
| 67 | YYDEFACT[S] = default reduction number in state s. Performed when |
| 68 | YYTABLE doesn't specify something else to do. Zero means the default |
| 69 | is an error. |
| 70 | |
| 71 | YYDEFGOTO[I] = default state to go to after a reduction of a rule |
| 72 | that generates variable NTOKENS + I, except when YYTABLE specifies |
| 73 | something else to do. |
| 74 | |
| 75 | YYPACT[S] = index in YYTABLE of the portion describing state S. |
| 76 | The lookahead token's number, I, is used to index that portion of |
| 77 | YYTABLE to find out what action to perform. |
| 78 | |
| 79 | If YYPACT[S] == YYPACT_NINF, if YYPACT[S] + I is outside the bounds |
| 80 | of YYTABLE (from 0 to YYLAST), or I is outside the bounds for portion |
| 81 | S (that is, YYCHECK[YYPACT[S] + I] != I), then the default action |
| 82 | (that is, YYDEFACT[S]) should be used instead of YYTABLE. Otherwise, |
| 83 | the value YYTABLE[YYPACT[S] + I] should be used even if |
| 84 | YYPACT[S] < 0. |
| 85 | |
| 86 | If the value in YYTABLE is positive, we shift the token and go to |
| 87 | that state. |
| 88 | |
| 89 | If the value is negative, it is minus a rule number to reduce by. |
| 90 | |
| 91 | If the value is YYTABLE_NINF, it's a syntax error. |
| 92 | |
| 93 | YYPGOTO[I] = the index in YYTABLE of the portion describing what to |
| 94 | do after reducing a rule that derives variable I + NTOKENS. This |
| 95 | portion is indexed by the parser state number, S, as of before the |
| 96 | text for this nonterminal was read. |
| 97 | |
| 98 | If YYPGOTO[I] + S is outside the bounds of YYTABLE (from 0 to YYLAST) |
| 99 | or if S is outside the bounds of the portion for I (that is, |
| 100 | YYCHECK[YYPGOTO[I] + S] != S), then the default state (that is, |
| 101 | YYDEFGOTO[I]) should be used instead of YYTABLE. Otherwise, |
| 102 | YYTABLE[YYPGOTO[I] + S] is the state to go to even if YYPGOTO[I] < 0. |
| 103 | |
| 104 | When the above YYPACT, YYPGOTO, and YYCHECK tests determine that a |
| 105 | value from YYTABLE should be used, that value is never zero, so it is |
| 106 | useless to check for zero. When those tests indicate that the value |
| 107 | from YYDEFACT or YYDEFGOTO should be used instead, the value from |
| 108 | YYTABLE *might* be zero, which, as a consequence of the way in which |
| 109 | the tables are constructed, also happens to indicate that YYDEFACT or |
| 110 | YYDEFGOTO should be used. However, the YYTABLE value cannot be |
| 111 | trusted when the YYDEFACT or YYDEFGOTO value should be used. In |
| 112 | summary, forget about zero values in YYTABLE. |
| 113 | */ |
| 114 | |
| 115 | extern int nvectors; |
| 116 | |
| 117 | typedef int base_number; |
| 118 | extern base_number *base; |
| 119 | /* A distinguished value of BASE, negative infinite. During the |
| 120 | computation equals to BASE_MINIMUM, later mapped to BASE_NINF to |
| 121 | keep parser tables small. */ |
| 122 | extern base_number base_ninf; |
| 123 | |
| 124 | extern unsigned int *conflict_table; |
| 125 | extern unsigned int *conflict_list; |
| 126 | extern int conflict_list_cnt; |
| 127 | |
| 128 | extern base_number *table; |
| 129 | extern base_number *check; |
| 130 | /* The value used in TABLE to denote explicit syntax errors |
| 131 | (%nonassoc), a negative infinite. */ |
| 132 | extern base_number table_ninf; |
| 133 | |
| 134 | extern state_number *yydefgoto; |
| 135 | extern rule_number *yydefact; |
| 136 | extern int high; |
| 137 | |
| 138 | void tables_generate (void); |
| 139 | void tables_free (void); |
| 140 | |
| 141 | #endif /* !TABLES_H_ */ |