1 | /* Subroutines for bison |
2 | |
3 | Copyright (C) 1984, 1989, 2000-2002, 2007, 2009-2015, 2018-2019 Free |
4 | Software Foundation, Inc. |
5 | |
6 | This file is part of Bison, the GNU Compiler Compiler. |
7 | |
8 | This program is free software: you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by |
10 | the Free Software Foundation, either version 3 of the License, or |
11 | (at your option) any later version. |
12 | |
13 | This program is distributed in the hope that it will be useful, |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
16 | GNU General Public License for more details. |
17 | |
18 | You should have received a copy of the GNU General Public License |
19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
20 | |
21 | #ifndef CLOSURE_H_ |
22 | # define CLOSURE_H_ |
23 | |
24 | # include "gram.h" |
25 | |
26 | /* Allocates the itemset and ruleset vectors, and precomputes useful |
27 | data so that closure can be called. n is the number of elements to |
28 | allocate for itemset. */ |
29 | |
30 | void closure_new (unsigned n); |
31 | |
32 | |
33 | /* Given the kernel (aka core) of a state (a sorted vector of item numbers |
34 | ITEMS, of length N), set up RULESET and ITEMSET to indicate what |
35 | rules could be run and which items could be accepted when those |
36 | items are the active ones. */ |
37 | |
38 | void closure (item_number const *items, size_t n); |
39 | |
40 | |
41 | /* Free ITEMSET, RULESET and internal data. */ |
42 | |
43 | void closure_free (void); |
44 | |
45 | |
46 | /* ITEMSET is a sorted vector of item numbers; NITEMSET is its size |
47 | (actually, points to just beyond the end of the part of it that is |
48 | significant). CLOSURE places there the indices of all items which |
49 | represent units of input that could arrive next. */ |
50 | |
51 | extern item_number *itemset; |
52 | extern size_t nitemset; |
53 | |
54 | #endif /* !CLOSURE_H_ */ |
55 | |