X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/fb9087861fd4b7de68fb8e86d08d4f07fd77238d..a68b1f237e63c96ee905916424013f79d01908ba:/src/closure.c
diff --git a/src/closure.c b/src/closure.c
index ac37b2c0..d9bc5ffa 100644
--- a/src/closure.c
+++ b/src/closure.c
@@ -1,49 +1,50 @@
-/* Subroutines for bison
- Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
+/* Closures for Bison
+
+ Copyright (C) 1984, 1989, 2000-2002, 2004-2005, 2007, 2009-2012 Free
+ Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
- Bison 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 2, or (at your option)
- any later version.
+ 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.
- Bison 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.
+ 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 Bison; see the file COPYING. If not, write to the Free
- Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
- 02111-1307, USA. */
+ along with this program. If not, see . */
+#include
#include "system.h"
+
+#include
+#include
+#include
+
+#include "closure.h"
+#include "derives.h"
#include "getargs.h"
#include "gram.h"
#include "reader.h"
-#include "closure.h"
-#include "derives.h"
-#include "warshall.h"
+#include "symtab.h"
-/* ITEMSETSIZE is the size of the array ITEMSET. */
-short *itemset;
-size_t itemsetsize;
+/* NITEMSET is the size of the array ITEMSET. */
+item_number *itemset;
+size_t nitemset;
-static unsigned *ruleset;
+static bitset ruleset;
/* internal data. See comments before set_fderives and set_firsts. */
-static unsigned *fderives;
-static unsigned *firsts;
-
-#define FDERIVES(Symbol) (fderives + (Symbol) * rulesetsize)
-#define FIRSTS(Symbol) (firsts + (Symbol) * varsetsize)
+static bitsetv fderives = NULL;
+static bitsetv firsts = NULL;
-/* number of words required to hold a bit for each rule */
-static int rulesetsize;
-
-/* number of words required to hold a bit for each variable */
-static int varsetsize;
+/* Retrieve the FDERIVES/FIRSTS sets of the nonterminals numbered Var. */
+#define FDERIVES(Var) fderives[(Var) - ntokens]
+#define FIRSTS(Var) firsts[(Var) - ntokens]
/*-----------------.
@@ -51,34 +52,37 @@ static int varsetsize;
`-----------------*/
static void
-print_closure (int n)
+print_closure (char const *title, item_number *array, size_t size)
{
- int i;
- fprintf (stderr, "n = %d\n", n);
- for (i = 0; i < itemsetsize; ++i)
- fprintf (stderr, " %d\n", itemset[i]);
- fprintf (stderr, "\n\n");
+ 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)
{
- int i;
- int j;
- unsigned *rowp;
+ symbol_number i, j;
fprintf (stderr, "FIRSTS\n");
-
for (i = ntokens; i < nsyms; i++)
{
- fprintf (stderr, "\t%s firsts\n", tags[i]);
-
- rowp = FIRSTS (i - ntokens);
-
- for (j = 0; j < nvars; j++)
- if (BITISSET (rowp, j))
- fprintf (stderr, "\t\t%d (%s)\n", j + ntokens, tags[j + ntokens]);
+ 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");
}
@@ -88,67 +92,55 @@ static void
print_fderives (void)
{
int i;
- int j;
- unsigned *rp;
+ rule_number r;
fprintf (stderr, "FDERIVES\n");
-
for (i = ntokens; i < nsyms; i++)
{
- fprintf (stderr, "\t%s derives\n", tags[i]);
- rp = FDERIVES (i);
-
- for (j = 0; j <= nrules; j++)
- if (BITISSET (rp, j))
- fprintf (stderr, "\t\t%d (%s)\n", j, tags[j]);
+ 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 by NVARS bit matrix 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, 5 - ntokens] in firsts is set. |
-`-------------------------------------------------------------------*/
+/*------------------------------------------------------------------.
+| 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)
{
- unsigned *row;
- int symbol;
- short *sp;
- int rowsize;
+ symbol_number i, j;
- int i;
+ firsts = bitsetv_create (nvars, nvars, BITSET_FIXED);
- varsetsize = rowsize = WORDSIZE (nvars);
-
- firsts = XCALLOC (unsigned, nvars * rowsize);
-
- row = firsts;
for (i = ntokens; i < nsyms; i++)
- {
- sp = derives[i];
- while (*sp >= 0)
- {
- symbol = ritem[rule_table[*sp++].rhs];
- if (ISVAR (symbol))
- {
- symbol -= ntokens;
- SETBIT (row, symbol);
- }
- }
-
- row += rowsize;
- }
-
- RTC (firsts, nvars);
-
- if (trace_flag)
+ 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 ();
}
@@ -165,61 +157,33 @@ set_firsts (void)
static void
set_fderives (void)
{
- unsigned *rrow;
- unsigned *vrow;
- int j;
- unsigned cword;
- short *rp;
- int b;
-
- int ruleno;
- int i;
+ symbol_number i, j;
+ rule_number k;
- fderives = XCALLOC (unsigned, nvars * rulesetsize) - ntokens * rulesetsize;
+ fderives = bitsetv_create (nvars, nrules, BITSET_FIXED);
set_firsts ();
- rrow = FDERIVES (ntokens);
+ 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);
- for (i = ntokens; i < nsyms; i++)
- {
- vrow = FIRSTS (i - ntokens);
- cword = *vrow++;
- b = 0;
- for (j = ntokens; j < nsyms; j++)
- {
- if (cword & (1 << b))
- {
- rp = derives[j];
- while ((ruleno = *rp++) > 0)
- SETBIT (rrow, ruleno);
- }
-
- b++;
- if (b >= BITS_PER_WORD && j + 1 < nsyms)
- {
- cword = *vrow++;
- b = 0;
- }
- }
-
- rrow += rulesetsize;
- }
-
- if (trace_flag)
+ if (trace_flag & trace_sets)
print_fderives ();
- XFREE (firsts);
+ bitsetv_free (firsts);
}
+
void
-new_closure (int n)
+new_closure (unsigned int n)
{
- itemset = XCALLOC (short, n);
+ itemset = xnmalloc (n, sizeof *itemset);
- rulesetsize = WORDSIZE (nrules + 1);
- ruleset = XCALLOC (unsigned, rulesetsize);
+ ruleset = bitset_create (nrules, BITSET_FIXED);
set_fderives ();
}
@@ -227,85 +191,58 @@ new_closure (int n)
void
-closure (short *core, int n)
+closure (item_number *core, size_t n)
{
- int ruleno;
- short *csp;
+ /* Index over CORE. */
+ size_t c;
- int itemno;
- int i;
+ /* A bit index over RULESET. */
+ rule_number ruleno;
- if (trace_flag)
- {
- fprintf (stderr, "Entering closure (items = {");
- for (i = 0; i < n; ++i)
- fprintf (stderr, " %d ", core[i]);
- fprintf (stderr, "}, nitems = %d)\n", n);
- }
+ bitset_iterator iter;
- if (n == 0)
- {
- for (i = 0; i < rulesetsize; ++i)
- ruleset[i] = FDERIVES (start_symbol)[i];
- }
- else
- {
- for (i = 0; i < rulesetsize; ++i)
- ruleset[i] = 0;
+ if (trace_flag & trace_sets)
+ print_closure ("input", core, n);
- for (i = 0; i < n; ++i)
- {
- int symbol = ritem[core[i]];
- if (ISVAR (symbol))
- {
- int j;
- for (j = 0; j < rulesetsize; ++j)
- ruleset[j] |= FDERIVES (symbol)[j];
- }
- }
- }
+ bitset_zero (ruleset);
+
+ for (c = 0; c < n; ++c)
+ if (ISVAR (ritem[core[c]]))
+ bitset_or (ruleset, ruleset, FDERIVES (ritem[core[c]]));
- ruleno = 0;
- itemsetsize = 0;
- csp = core;
- for (i = 0; i < rulesetsize; ++i)
+ /* 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)
{
- int word = ruleset[i];
- if (word == 0)
- {
- ruleno += BITS_PER_WORD;
- }
- else
+ item_number itemno = rules[ruleno].rhs - ritem;
+ while (c < n && core[c] < itemno)
{
- int b;
-
- for (b = 0; b < BITS_PER_WORD; b++)
- {
- if (word & (1 << b))
- {
- itemno = rule_table[ruleno].rhs;
- while (csp < (core + n) && *csp < itemno)
- itemset[itemsetsize++] = *csp++;
- itemset[itemsetsize++] = itemno;
- }
-
- ruleno++;
- }
+ itemset[nitemset] = core[c];
+ nitemset++;
+ c++;
}
- }
+ itemset[nitemset] = itemno;
+ nitemset++;
+ };
- while (csp < (core + n))
- itemset[itemsetsize++] = *csp++;
+ while (c < n)
+ {
+ itemset[nitemset] = core[c];
+ nitemset++;
+ c++;
+ }
- if (trace_flag)
- print_closure (n);
+ if (trace_flag & trace_sets)
+ print_closure ("output", itemset, nitemset);
}
void
free_closure (void)
{
- XFREE (itemset);
- XFREE (ruleset);
- XFREE (fderives + ntokens * rulesetsize);
+ free (itemset);
+ bitset_free (ruleset);
+ bitsetv_free (fderives);
}