| Index: bison/src/bison/2.4.1/bison-2.4.1-src/src/closure.c
|
| ===================================================================
|
| --- bison/src/bison/2.4.1/bison-2.4.1-src/src/closure.c (revision 0)
|
| +++ bison/src/bison/2.4.1/bison-2.4.1-src/src/closure.c (revision 0)
|
| @@ -0,0 +1,249 @@
|
| +/* Closures for Bison
|
| +
|
| + Copyright (C) 1984, 1989, 2000, 2001, 2002, 2004, 2005, 2007 Free
|
| + Software Foundation, Inc.
|
| +
|
| + This file is part of Bison, the GNU Compiler Compiler.
|
| +
|
| + 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.
|
| +
|
| + 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 this program. If not, see <http://www.gnu.org/licenses/>. */
|
| +
|
| +#include <config.h>
|
| +#include "system.h"
|
| +
|
| +#include <bitset.h>
|
| +#include <bitsetv-print.h>
|
| +#include <bitsetv.h>
|
| +#include <quotearg.h>
|
| +
|
| +#include "closure.h"
|
| +#include "derives.h"
|
| +#include "getargs.h"
|
| +#include "gram.h"
|
| +#include "reader.h"
|
| +#include "symtab.h"
|
| +
|
| +/* NITEMSET is the size of the array ITEMSET. */
|
| +item_number *itemset;
|
| +size_t nitemset;
|
| +
|
| +static bitset ruleset;
|
| +
|
| +/* internal data. See comments before set_fderives and set_firsts. */
|
| +static bitsetv fderives = NULL;
|
| +static bitsetv firsts = NULL;
|
| +
|
| +/* Retrieve the FDERIVES/FIRSTS sets of the nonterminals numbered Var. */
|
| +#define FDERIVES(Var) fderives[(Var) - ntokens]
|
| +#define FIRSTS(Var) firsts[(Var) - ntokens]
|
| +
|
| +
|
| +/*-----------------.
|
| +| Debugging code. |
|
| +`-----------------*/
|
| +
|
| +static void
|
| +print_closure (char const *title, item_number *array, size_t size)
|
| +{
|
| + size_t i;
|
| + fprintf (stderr, "Closure: %s\n", title);
|
| + for (i = 0; i < size; ++i)
|
| + {
|
| + item_number *rp;
|
| + fprintf (stderr, " %2d: .", array[i]);
|
| + for (rp = &ritem[array[i]]; *rp >= 0; ++rp)
|
| + fprintf (stderr, " %s", symbols[*rp]->tag);
|
| + fprintf (stderr, " (rule %d)\n", -*rp - 1);
|
| + }
|
| + fputs ("\n\n", stderr);
|
| +}
|
| +
|
| +
|
| +static void
|
| +print_firsts (void)
|
| +{
|
| + symbol_number i, j;
|
| +
|
| + fprintf (stderr, "FIRSTS\n");
|
| + for (i = ntokens; i < nsyms; i++)
|
| + {
|
| + bitset_iterator iter;
|
| + fprintf (stderr, "\t%s firsts\n", symbols[i]->tag);
|
| + BITSET_FOR_EACH (iter, FIRSTS (i), j, 0)
|
| + {
|
| + fprintf (stderr, "\t\t%s\n",
|
| + symbols[j + ntokens]->tag);
|
| + }
|
| + }
|
| + fprintf (stderr, "\n\n");
|
| +}
|
| +
|
| +
|
| +static void
|
| +print_fderives (void)
|
| +{
|
| + int i;
|
| + rule_number r;
|
| +
|
| + fprintf (stderr, "FDERIVES\n");
|
| + for (i = ntokens; i < nsyms; i++)
|
| + {
|
| + bitset_iterator iter;
|
| + fprintf (stderr, "\t%s derives\n", symbols[i]->tag);
|
| + BITSET_FOR_EACH (iter, FDERIVES (i), r, 0)
|
| + {
|
| + fprintf (stderr, "\t\t%3d ", r);
|
| + rule_rhs_print (&rules[r], stderr);
|
| + }
|
| + }
|
| + fprintf (stderr, "\n\n");
|
| +}
|
| +
|
| +/*------------------------------------------------------------------.
|
| +| Set FIRSTS to be an NVARS array of NVARS bitsets indicating which |
|
| +| items can represent the beginning of the input corresponding to |
|
| +| which other items. |
|
| +| |
|
| +| For example, if some rule expands symbol 5 into the sequence of |
|
| +| symbols 8 3 20, the symbol 8 can be the beginning of the data for |
|
| +| symbol 5, so the bit [8 - ntokens] in first[5 - ntokens] (= FIRST |
|
| +| (5)) is set. |
|
| +`------------------------------------------------------------------*/
|
| +
|
| +static void
|
| +set_firsts (void)
|
| +{
|
| + symbol_number i, j;
|
| +
|
| + firsts = bitsetv_create (nvars, nvars, BITSET_FIXED);
|
| +
|
| + for (i = ntokens; i < nsyms; i++)
|
| + for (j = 0; derives[i - ntokens][j]; ++j)
|
| + {
|
| + item_number sym = derives[i - ntokens][j]->rhs[0];
|
| + if (ISVAR (sym))
|
| + bitset_set (FIRSTS (i), sym - ntokens);
|
| + }
|
| +
|
| + if (trace_flag & trace_sets)
|
| + bitsetv_matrix_dump (stderr, "RTC: Firsts Input", firsts);
|
| + bitsetv_reflexive_transitive_closure (firsts);
|
| + if (trace_flag & trace_sets)
|
| + bitsetv_matrix_dump (stderr, "RTC: Firsts Output", firsts);
|
| +
|
| + if (trace_flag & trace_sets)
|
| + print_firsts ();
|
| +}
|
| +
|
| +/*-------------------------------------------------------------------.
|
| +| Set FDERIVES to an NVARS by NRULES matrix of bits indicating which |
|
| +| rules can help derive the beginning of the data for each |
|
| +| nonterminal. |
|
| +| |
|
| +| For example, if symbol 5 can be derived as the sequence of symbols |
|
| +| 8 3 20, and one of the rules for deriving symbol 8 is rule 4, then |
|
| +| the [5 - NTOKENS, 4] bit in FDERIVES is set. |
|
| +`-------------------------------------------------------------------*/
|
| +
|
| +static void
|
| +set_fderives (void)
|
| +{
|
| + symbol_number i, j;
|
| + rule_number k;
|
| +
|
| + fderives = bitsetv_create (nvars, nrules, BITSET_FIXED);
|
| +
|
| + set_firsts ();
|
| +
|
| + for (i = ntokens; i < nsyms; ++i)
|
| + for (j = ntokens; j < nsyms; ++j)
|
| + if (bitset_test (FIRSTS (i), j - ntokens))
|
| + for (k = 0; derives[j - ntokens][k]; ++k)
|
| + bitset_set (FDERIVES (i), derives[j - ntokens][k]->number);
|
| +
|
| + if (trace_flag & trace_sets)
|
| + print_fderives ();
|
| +
|
| + bitsetv_free (firsts);
|
| +}
|
| +
|
| +
|
| +
|
| +void
|
| +new_closure (unsigned int n)
|
| +{
|
| + itemset = xnmalloc (n, sizeof *itemset);
|
| +
|
| + ruleset = bitset_create (nrules, BITSET_FIXED);
|
| +
|
| + set_fderives ();
|
| +}
|
| +
|
| +
|
| +
|
| +void
|
| +closure (item_number *core, size_t n)
|
| +{
|
| + /* Index over CORE. */
|
| + size_t c;
|
| +
|
| + /* A bit index over RULESET. */
|
| + rule_number ruleno;
|
| +
|
| + bitset_iterator iter;
|
| +
|
| + if (trace_flag & trace_sets)
|
| + print_closure ("input", core, n);
|
| +
|
| + bitset_zero (ruleset);
|
| +
|
| + for (c = 0; c < n; ++c)
|
| + if (ISVAR (ritem[core[c]]))
|
| + bitset_or (ruleset, ruleset, FDERIVES (ritem[core[c]]));
|
| +
|
| + /* core is sorted on item index in ritem, which is sorted on rule number.
|
| + Compute itemset with the same sort. */
|
| + nitemset = 0;
|
| + c = 0;
|
| + BITSET_FOR_EACH (iter, ruleset, ruleno, 0)
|
| + {
|
| + item_number itemno = rules[ruleno].rhs - ritem;
|
| + while (c < n && core[c] < itemno)
|
| + {
|
| + itemset[nitemset] = core[c];
|
| + nitemset++;
|
| + c++;
|
| + }
|
| + itemset[nitemset] = itemno;
|
| + nitemset++;
|
| + };
|
| +
|
| + while (c < n)
|
| + {
|
| + itemset[nitemset] = core[c];
|
| + nitemset++;
|
| + c++;
|
| + }
|
| +
|
| + if (trace_flag & trace_sets)
|
| + print_closure ("output", itemset, nitemset);
|
| +}
|
| +
|
| +
|
| +void
|
| +free_closure (void)
|
| +{
|
| + free (itemset);
|
| + bitset_free (ruleset);
|
| + bitsetv_free (fderives);
|
| +}
|
|
|
| Property changes on: bison\src\bison\2.4.1\bison-2.4.1-src\src\closure.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
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|
|