projects / bison.git / blame
| Commit | Line | Data |
|---|---|---|
| c29240e7 | 1 | /* Subroutines for bison |
| fb908786 | 2 | Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc. |
| c29240e7 AD |
3 | |
| 4 | This file is part of Bison, the GNU Compiler Compiler. | |
| 5 | ||
| 6 | Bison is free software; you can redistribute it and/or modify it | |
| 7 | under the terms of the GNU General Public License as published by | |
| 8 | the Free Software Foundation; either version 2, or (at your option) | |
| 9 | any later version. | |
| 10 | ||
| 11 | Bison is distributed in the hope that it will be useful, but | |
| 12 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 14 | General Public License for more details. | |
| 15 | ||
| 16 | You should have received a copy of the GNU General Public License | |
| 17 | along with Bison; see the file COPYING. If not, write to the Free | |
| 18 | Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA | |
| 19 | 02111-1307, USA. */ | |
| 20 | ||
| 340ef489 AD |
21 | #ifndef CLOSURE_H_ |
| 22 | # define CLOSURE_H_ | |
| c29240e7 AD |
23 | |
| 24 | /* Subroutines of file LR0.c. */ | |
| 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 new_closure PARAMS ((int n)); | |
| 31 | ||
| 32 | ||
| b2872512 AD |
33 | /* Given the kernel (aka core) of a state (a 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. | |
| c29240e7 AD |
37 | |
| 38 | ruleset contains a bit for each rule. closure sets the bits for | |
| 39 | all rules which could potentially describe the next input to be | |
| 40 | read. | |
| 41 | ||
| b2872512 AD |
42 | ITEMSET is a vector of item numbers; NITEMSET is its size |
| 43 | 9actually, points to just beyond the end of the part of it that is | |
| 44 | significant). closure places there the indices of all items which | |
| 45 | represent units of input that could arrive next. */ | |
| c29240e7 AD |
46 | |
| 47 | void closure PARAMS ((short *items, int n)); | |
| 48 | ||
| 49 | ||
| 50 | /* Frees itemset, ruleset and internal data. */ | |
| 51 | ||
| 52 | void free_closure PARAMS ((void)); | |
| 340ef489 AD |
53 | |
| 54 | extern short *itemset; | |
| b2872512 | 55 | extern int nitemset; |
| 340ef489 AD |
56 | |
| 57 | #endif /* !CLOSURE_H_ */ |