* src/closure.c (set_firsts): De-obfuscate.

[bison.git] / src / closure.c

diff --git a/src/closure.c b/src/closure.c
index 31073257970bd2b0575fd252b322f90e0bb97054..849b0b6288a5d13c3e167fb2be45f38064053d9f 100644 (file)
--- a/src/closure.c
+++ b/src/closure.c
@@ -1,5 +1,5 @@
 /* Subroutines for bison
 /* Subroutines for bison

-   Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc.
+   Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 


@@ -18,32 +18,33 @@
    Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
    02111-1307, USA.  */
 
    Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
    02111-1307, USA.  */
 

-

 #include "system.h"
 #include "system.h"

-#include "alloc.h"
+#include "getargs.h"

 #include "gram.h"
 #include "gram.h"

+#include "reader.h"

 #include "closure.h"
 #include "closure.h"

+#include "derives.h"
+#include "warshall.h"

 
 

-extern short **derives;
-extern char **tags;
-
-extern void RTC PARAMS ((unsigned *, int));
-
+/* ITEMSETSIZE is the size of the array ITEMSET.  */

 short *itemset;
 short *itemset;

-short *itemsetend;
+int itemsetsize;
+

 static unsigned *ruleset;
 
 /* internal data.  See comments before set_fderives and set_firsts.  */
 static unsigned *fderives;
 static unsigned *firsts;
 
 static unsigned *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)
+

 /* 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;
 \f
 /* 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;
 \f

-#if DEBUG

 
 /*-----------------.
 | Debugging code.  |
 
 /*-----------------.
 | Debugging code.  |


@@ -52,11 +53,11 @@ static int varsetsize;
 static void
 print_closure (int n)
 {
 static void
 print_closure (int n)
 {

-  short *isp;
-
-  printf ("\n\nn = %d\n\n", n);
-  for (isp = itemset; isp < itemsetend; isp++)
-    printf ("   %d\n", *isp);
+  int i;
+  fprintf (stderr, "n = %d\n", n);
+  for (i = 0; i < itemsetsize; ++i)
+    fprintf (stderr, "   %d\n", itemset[i]);
+  fprintf (stderr, "\n\n");

 }
 
 
 }
 
 


@@ -67,18 +68,19 @@ print_firsts (void)
   int j;
   unsigned *rowp;
 
   int j;
   unsigned *rowp;
 

-  printf ("\n\n\nFIRSTS\n\n");
+  fprintf (stderr, "FIRSTS\n");

 
   for (i = ntokens; i < nsyms; i++)
     {
 
   for (i = ntokens; i < nsyms; i++)
     {

-      printf ("\n\n%s firsts\n\n", tags[i]);
+      fprintf (stderr, "\t%s firsts\n", tags[i]);

 
 

-      rowp = firsts + ((i - ntokens) * varsetsize);
+      rowp = FIRSTS (i - ntokens);

 
       for (j = 0; j < nvars; j++)
        if (BITISSET (rowp, j))
 
       for (j = 0; j < nvars; j++)
        if (BITISSET (rowp, j))

-         printf ("   %s\n", tags[j + ntokens]);
+         fprintf (stderr, "\t\t%d (%s)\n", j + ntokens, tags[j + ntokens]);

     }
     }

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

 }
 
 
 }
 
 


@@ -89,21 +91,25 @@ print_fderives (void)
   int j;
   unsigned *rp;
 
   int j;
   unsigned *rp;
 

-  printf ("\n\n\nFDERIVES\n");
+  fprintf (stderr, "FDERIVES\n");

 
   for (i = ntokens; i < nsyms; i++)
     {
 
   for (i = ntokens; i < nsyms; i++)
     {

-      printf ("\n\n%s derives\n\n", tags[i]);
-      rp = fderives + i * rulesetsize;
+      fprintf (stderr, "\t%s derives\n", tags[i]);
+      rp = FDERIVES (i);

 
       for (j = 0; j <= nrules; j++)
        if (BITISSET (rp, j))
 
       for (j = 0; j <= nrules; j++)
        if (BITISSET (rp, j))

-         printf ("   %d\n", 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);
+         }

     }
     }

-
-  fflush (stdout);
+  fprintf (stderr, "\n\n");

 }
 }

-#endif

 \f
 /*-------------------------------------------------------------------.
 | Set FIRSTS to be an NVARS by NVARS bit matrix indicating which     |
 \f
 /*-------------------------------------------------------------------.
 | Set FIRSTS to be an NVARS by NVARS bit matrix indicating which     |


@@ -118,39 +124,29 @@ print_fderives (void)
 static void
 set_firsts (void)
 {
 static void
 set_firsts (void)
 {

-  unsigned *row;
-  int symbol;
-  short *sp;

   int rowsize;
 
   int rowsize;
 

-  int i;
+  int i, j;

 
   varsetsize = rowsize = WORDSIZE (nvars);
 
 
   varsetsize = rowsize = WORDSIZE (nvars);
 

-  firsts = NEW2 (nvars * rowsize, unsigned);
+  firsts = XCALLOC (unsigned, nvars * rowsize);

 
 

-  row = firsts;

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

-    {
-      sp = derives[i];
-      while (*sp >= 0)
-       {
-         symbol = ritem[rrhs[*sp++]];
-         if (ISVAR (symbol))
-           {
-             symbol -= ntokens;
-             SETBIT (row, symbol);
-           }
-       }
-
-      row += rowsize;
-    }
+    for (j = 0; derives[i][j] >= 0; ++j)
+      {
+       int symbol = ritem[rule_table[derives[i][j]].rhs];
+       if (ISVAR (symbol))
+         {
+           symbol -= ntokens;
+           SETBIT (FIRSTS (i - ntokens), symbol);
+         }
+      }

 
   RTC (firsts, nvars);
 
 
   RTC (firsts, nvars);
 

-#ifdef DEBUG
-  print_firsts ();
-#endif
+  if (trace_flag)
+    print_firsts ();

 }
 
 /*-------------------------------------------------------------------.
 }
 
 /*-------------------------------------------------------------------.


@@ -176,15 +172,15 @@ set_fderives (void)
   int ruleno;
   int i;
 
   int ruleno;
   int i;
 

-  fderives = NEW2 (nvars * rulesetsize, unsigned) - ntokens * rulesetsize;
+  fderives = XCALLOC (unsigned, nvars * rulesetsize) - ntokens * rulesetsize;

 
   set_firsts ();
 
 
   set_firsts ();
 

-  rrow = fderives + ntokens * rulesetsize;
+  rrow = FDERIVES (ntokens);

 
   for (i = ntokens; i < nsyms; i++)
     {
 
   for (i = ntokens; i < nsyms; i++)
     {

-      vrow = firsts + ((i - ntokens) * varsetsize);
+      vrow = FIRSTS (i - ntokens);

       cword = *vrow++;
       b = 0;
       for (j = ntokens; j < nsyms; j++)
       cword = *vrow++;
       b = 0;
       for (j = ntokens; j < nsyms; j++)


@@ -193,9 +189,7 @@ set_fderives (void)
            {
              rp = derives[j];
              while ((ruleno = *rp++) > 0)
            {
              rp = derives[j];
              while ((ruleno = *rp++) > 0)

-               {
-                 SETBIT (rrow, ruleno);
-               }
+               SETBIT (rrow, ruleno);

            }
 
          b++;
            }
 
          b++;


@@ -209,21 +203,20 @@ set_fderives (void)
       rrow += rulesetsize;
     }
 
       rrow += rulesetsize;
     }
 

-#ifdef DEBUG
-  print_fderives ();
-#endif
+  if (trace_flag)
+    print_fderives ();

 
 

-  FREE (firsts);
+  XFREE (firsts);

 }
 \f
 
 void
 new_closure (int n)
 {
 }
 \f
 
 void
 new_closure (int n)
 {

-  itemset = NEW2 (n, short);
+  itemset = XCALLOC (short, n);

 
   rulesetsize = WORDSIZE (nrules + 1);
 
   rulesetsize = WORDSIZE (nrules + 1);

-  ruleset = NEW2 (rulesetsize, unsigned);
+  ruleset = XCALLOC (unsigned, rulesetsize);

 
   set_fderives ();
 }
 
   set_fderives ();
 }


@@ -233,89 +226,71 @@ new_closure (int n)
 void
 closure (short *core, int n)
 {
 void
 closure (short *core, int n)
 {

-  int ruleno;
-  unsigned word;
-  short *csp;
-  unsigned *dsp;
-  unsigned *rsp;
+  /* Index over CORE. */
+  int c;

 
 

-  short *csend;
-  unsigned *rsend;
-  int symbol;
-  int itemno;
+  /* Index over RULESET. */
+  int r;

 
 

-  rsp = ruleset;
-  rsend = ruleset + rulesetsize;
-  csend = core + n;
+  /* A bit index over RULESET. */
+  int ruleno;
+
+  if (trace_flag)
+    {
+      fprintf (stderr, "Entering closure (items = {");
+      for (c = 0; c < n; ++c)
+       fprintf (stderr, " %d ", core[c]);
+      fprintf (stderr, "})\n");
+    }

 
   if (n == 0)
     {
 
   if (n == 0)
     {

-      dsp = fderives + start_symbol * rulesetsize;
-      while (rsp < rsend)
-       *rsp++ = *dsp++;
+      for (r = 0; r < rulesetsize; ++r)
+       ruleset[r] = FDERIVES (start_symbol)[r];

     }
   else
     {
     }
   else
     {

-      while (rsp < rsend)
-       *rsp++ = 0;
+      for (r = 0; r < rulesetsize; ++r)
+       ruleset[r] = 0;

 
 

-      csp = core;
-      while (csp < csend)
-       {
-         symbol = ritem[*csp++];
-         if (ISVAR (symbol))
-           {
-             dsp = fderives + symbol * rulesetsize;
-             rsp = ruleset;
-             while (rsp < rsend)
-               *rsp++ |= *dsp++;
-           }
-       }
+      for (c = 0; c < n; ++c)
+       if (ISVAR (ritem[core[c]]))
+         for (r = 0; r < rulesetsize; ++r)
+           ruleset[r] |= FDERIVES (ritem[core[c]])[r];

     }
 
     }
 

-  ruleno = 0;
-  itemsetend = itemset;
-  csp = core;
-  rsp = ruleset;
-  while (rsp < rsend)
+  itemsetsize = 0;
+  c = 0;
+  for (ruleno = 0; ruleno < rulesetsize * BITS_PER_WORD; ++ruleno)
+    if (BITISSET (ruleset, ruleno))
+      {
+       int itemno = rule_table[ruleno].rhs;
+       while (c < n && core[c] < itemno)
+         {
+           itemset[itemsetsize] = core[c];
+           itemsetsize++;
+           c++;
+         }
+       itemset[itemsetsize] = itemno;
+       itemsetsize++;
+      }
+
+  while (c < n)

     {
     {

-      word = *rsp++;
-      if (word == 0)
-       {
-         ruleno += BITS_PER_WORD;
-       }
-      else
-       {
-         int b;
-
-         for (b = 0; b < BITS_PER_WORD; b++)
-           {
-             if (word & (1 << b))
-               {
-                 itemno = rrhs[ruleno];
-                 while (csp < csend && *csp < itemno)
-                   *itemsetend++ = *csp++;
-                 *itemsetend++ = itemno;
-               }
-
-             ruleno++;
-           }
-       }
+      itemset[itemsetsize] = core[c];
+      itemsetsize++;
+      c++;

     }
 
     }
 

-  while (csp < csend)
-    *itemsetend++ = *csp++;
-
-#if DEBUG
-  print_closure (n);
-#endif
+  if (trace_flag)
+    print_closure (n);

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

-  FREE (itemset);
-  FREE (ruleset);
-  FREE (fderives + ntokens * rulesetsize);
+  XFREE (itemset);
+  XFREE (ruleset);
+  XFREE (fderives + ntokens * rulesetsize);

 }
 }