maint: run "make update-copyright"

[bison.git] / src / closure.c

diff --git a/src/closure.c b/src/closure.c
index ad3a5be7af70a3870d6cbed9905646518285cd22..180e1dfc15ed259251a228caf8d263c9360270d2 100644 (file)
--- a/src/closure.c
+++ b/src/closure.c
@@ -1,49 +1,51 @@
-/* Subroutines for bison
-   Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
+/* Closures for Bison
+
+   Copyright (C) 1984, 1989, 2000, 2001, 2002, 2004, 2005, 2007, 2009
+   Free Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    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
 
    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 <http://www.gnu.org/licenses/>.  */

 
 

+#include <config.h>

 #include "system.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 "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;
-int 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.  */
 
 /* internal data.  See comments before set_fderives and set_firsts.  */

-static unsigned *fderives;
-static unsigned *firsts;
+static bitsetv fderives = NULL;
+static bitsetv firsts = NULL;

 
 

-#define FDERIVES(Symbol)   (fderives + (Symbol) * rulesetsize)
-#define   FIRSTS(Symbol)   (firsts   + (Symbol) * varsetsize)
-
-/* 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]

 \f
 
 /*-----------------.
 \f
 
 /*-----------------.


@@ -51,34 +53,37 @@ static int varsetsize;
 `-----------------*/
 
 static void
 `-----------------*/
 
 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)
 {
 }
 
 
 static void
 print_firsts (void)
 {

-  int i;
-  int j;
-  unsigned *rowp;
+  symbol_number i, j;

 
   fprintf (stderr, "FIRSTS\n");
 
   fprintf (stderr, "FIRSTS\n");

-

   for (i = ntokens; i < nsyms; i++)
     {
   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");
 }
     }
   fprintf (stderr, "\n\n");
 }


@@ -88,73 +93,55 @@ static void
 print_fderives (void)
 {
   int i;
 print_fderives (void)
 {
   int i;

-  int j;
-  unsigned *rp;
+  rule_number r;

 
   fprintf (stderr, "FDERIVES\n");
 
   fprintf (stderr, "FDERIVES\n");

-

   for (i = ntokens; i < nsyms; i++)
     {
   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))
-         {
-           short *rhsp;
-           fprintf (stderr, "\t\t%d:", j);
-           for (rhsp = ritem + rule_table[j].rhs; *rhsp > 0; ++rhsp)
-             fprintf (stderr, " %s", tags[*rhsp]);
-           fputc ('\n', stderr);
-         }
+      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");
 }
 \f
     }
   fprintf (stderr, "\n\n");
 }
 \f

-/*-------------------------------------------------------------------.
-| 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)
 {
 
 static void
 set_firsts (void)
 {

-  unsigned *row;
-  int symbol;
-  short *sp;
-  int rowsize;
-
-  int i;
-
-  varsetsize = rowsize = WORDSIZE (nvars);
+  symbol_number i, j;

 
 

-  firsts = XCALLOC (unsigned, nvars * rowsize);
+  firsts = bitsetv_create (nvars, nvars, BITSET_FIXED);

 
 

-  row = firsts;

   for (i = ntokens; i < nsyms; i++)
   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 ();
 }
 
     print_firsts ();
 }
 


@@ -171,61 +158,33 @@ set_firsts (void)
 static void
 set_fderives (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 ();
 
 
   set_firsts ();
 

-  rrow = FDERIVES (ntokens);
-
-  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;
-    }
+  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)
+  if (trace_flag & trace_sets)

     print_fderives ();
 
     print_fderives ();
 

-  XFREE (firsts);
+  bitsetv_free (firsts);

 }
 }

+

 \f
 
 void
 \f
 
 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 ();
 }
 
   set_fderives ();
 }


@@ -233,83 +192,58 @@ new_closure (int n)
 
 
 void
 
 
 void

-closure (short *core, int n)
+closure (item_number *core, size_t n)

 {
 {

-  int ruleno;

   /* Index over CORE. */
   /* Index over CORE. */

-  int c;
+  size_t c;

 
 

-  /* Index over RULESET. */
-  int r;
+  /* A bit index over RULESET. */
+  rule_number ruleno;

 
 

-  int itemno;
+  bitset_iterator iter;

 
 

-  if (trace_flag)
-    {
-      fprintf (stderr, "Entering closure (items = {");
-      for (c = 0; c < n; ++c)
-       fprintf (stderr, " %d ", core[c]);
-      fprintf (stderr, "})\n");
-    }
+  if (trace_flag & trace_sets)
+    print_closure ("input", core, n);

 
 

-  if (n == 0)
-    {
-      for (r = 0; r < rulesetsize; ++r)
-       ruleset[r] = FDERIVES (start_symbol)[r];
-    }
-  else
-    {
-      for (r = 0; r < rulesetsize; ++r)
-       ruleset[r] = 0;
+  bitset_zero (ruleset);

 
 

-      for (c = 0; c < n; ++c)
-       if (ISVAR (ritem[core[c]]))
-         for (r = 0; r < rulesetsize; ++r)
-           ruleset[r] |= FDERIVES (ritem[core[c]])[r];
-    }
+  for (c = 0; c < n; ++c)
+    if (ISVAR (ritem[core[c]]))
+      bitset_or (ruleset, ruleset, FDERIVES (ritem[core[c]]));

 
 

-  ruleno = 0;
-  itemsetsize = 0;
+  /* core is sorted on item index in ritem, which is sorted on rule number.
+     Compute itemset with the same sort.  */
+  nitemset = 0;

   c = 0;
   c = 0;

-  for (r = 0; r < rulesetsize; ++r)
+  BITSET_FOR_EACH (iter, ruleset, ruleno, 0)

     {
     {

-      int b;
-
-      for (b = 0; b < BITS_PER_WORD; b++)
+      item_number itemno = rules[ruleno].rhs - ritem;
+      while (c < n && core[c] < itemno)

        {
        {

-         if (ruleset[r] & (1 << b))
-           {
-             itemno = rule_table[ruleno].rhs;
-             while (c < n && core[c] < itemno)
-               {
-                 itemset[itemsetsize] = core[c];
-                 itemsetsize++;
-                 c++;
-               }
-             itemset[itemsetsize] = itemno;
-             itemsetsize++;
-           }
-
-         ruleno++;
+         itemset[nitemset] = core[c];
+         nitemset++;
+         c++;

        }
        }

-    }
+      itemset[nitemset] = itemno;
+      nitemset++;
+    };

 
   while (c < n)
     {
 
   while (c < n)
     {

-      itemset[itemsetsize] = core[c];
-      itemsetsize++;
+      itemset[nitemset] = core[c];
+      nitemset++;

       c++;
     }
 
       c++;
     }
 

-  if (trace_flag)
-    print_closure (n);
+  if (trace_flag & trace_sets)
+    print_closure ("output", itemset, nitemset);

 }
 
 
 void
 free_closure (void)
 {
 }
 
 
 void
 free_closure (void)
 {

-  XFREE (itemset);
-  XFREE (ruleset);
-  XFREE (fderives + ntokens * rulesetsize);
+  free (itemset);
+  bitset_free (ruleset);
+  bitsetv_free (fderives);

 }
 }