* src/state.h (SHIFT_IS_ERROR, SHIFT_IS_GOTO, SHIFT_IS_SHIFT): New.

[bison.git] / src / lalr.c

diff --git a/src/lalr.c b/src/lalr.c
index 46ec2eef4a848d02d43f1c5002bf53bd79f9adb8..e6738bdac55172a97d92f58c83ebde44d4ae5a18 100644 (file)
--- a/src/lalr.c
+++ b/src/lalr.c
@@ -1,5 +1,5 @@
 /* Compute look-ahead criteria for bison,
 /* Compute look-ahead criteria for bison,

-   Copyright 1984, 1986, 1989, 2000 Free Software Foundation, Inc.
+   Copyright 1984, 1986, 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.
 


@@ -31,6 +31,7 @@
 #include "lalr.h"
 #include "nullable.h"
 #include "derives.h"
 #include "lalr.h"
 #include "nullable.h"
 #include "derives.h"

+#include "getargs.h"

 
 /* All the decorated states, indexed by the state number.  Warning:
    there is a state_TABLE in LR0.c, but it is different and static.
 
 /* All the decorated states, indexed by the state number.  Warning:
    there is a state_TABLE in LR0.c, but it is different and static.


@@ -41,78 +42,69 @@ int tokensetsize;
 short *LAruleno;
 unsigned *LA;
 
 short *LAruleno;
 unsigned *LA;
 

+static int ngotos;

 short *goto_map;
 short *from_state;
 short *to_state;
 
 short *goto_map;
 short *from_state;
 short *to_state;
 

-extern void berror PARAMS ((const char *));
+/* And for the famous F variable, which name is so descriptive that a
+   comment is hardly needed.  <grin>.  */
+static unsigned *F = NULL;
+#define F(Rule)  (F + (Rule) * tokensetsize)

 
 

-static int infinity;
-static int maxrhs;
-static int ngotos;
-static unsigned *F;

 static short **includes;
 static shorts **lookback;
 static short **includes;
 static shorts **lookback;

+
+
+/*---------------------------------------------------------------.
+| digraph & traverse.                                            |
+|                                                                |
+| The following variables are used as common storage between the |
+| two.                                                           |
+`---------------------------------------------------------------*/
+

 static short **R;
 static short *INDEX;
 static short *VERTICES;
 static int top;
 static short **R;
 static short *INDEX;
 static short *VERTICES;
 static int top;

-
+static int infinity;

 
 static void
 traverse (int i)
 {
 
 static void
 traverse (int i)
 {

-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;

   int j;
   int j;

-  short *rp;
-
+  size_t k;

   int height;
   int height;

-  unsigned *base;
+  size_t size = F (i + 1) - F(i);

 
   VERTICES[++top] = i;
   INDEX[i] = height = top;
 
 
   VERTICES[++top] = i;
   INDEX[i] = height = top;
 

-  base = F + i * tokensetsize;
-  fp3 = base + tokensetsize;
-
-  rp = R[i];
-  if (rp)
-    {
-      while ((j = *rp++) >= 0)
-       {
-         if (INDEX[j] == 0)
-           traverse (j);
-
-         if (INDEX[i] > INDEX[j])
-           INDEX[i] = INDEX[j];
+  if (R[i])
+    for (j = 0; R[i][j] >= 0; ++j)
+      {
+       if (INDEX[R[i][j]] == 0)
+         traverse (R[i][j]);

 
 

-         fp1 = base;
-         fp2 = F + j * tokensetsize;
+       if (INDEX[i] > INDEX[R[i][j]])
+         INDEX[i] = INDEX[R[i][j]];

 
 

-         while (fp1 < fp3)
-           *fp1++ |= *fp2++;
-       }
-    }
+       for (k = 0; k < size; ++k)
+         F (i)[k] |= F (R[i][j])[k];
+      }

 
   if (INDEX[i] == height)
 
   if (INDEX[i] == height)

-    {
-      for (;;)
-       {
-         j = VERTICES[top--];
-         INDEX[j] = infinity;
-
-         if (i == j)
-           break;
+    for (;;)
+      {
+       j = VERTICES[top--];
+       INDEX[j] = infinity;

 
 

-         fp1 = base;
-         fp2 = F + j * tokensetsize;
+       if (i == j)
+         break;

 
 

-         while (fp1 < fp3)
-           *fp2++ = *fp1++;
-       }
-    }
+       for (k = 0; k < size; ++k)
+         F (i)[k] = F (j)[k];
+      }

 }
 
 
 }
 
 


@@ -132,10 +124,8 @@ digraph (short **relation)
     INDEX[i] = 0;
 
   for (i = 0; i < ngotos; i++)
     INDEX[i] = 0;
 
   for (i = 0; i < ngotos; i++)

-    {
-      if (INDEX[i] == 0 && R[i])
-       traverse (i);
-    }
+    if (INDEX[i] == 0 && R[i])
+      traverse (i);

 
   XFREE (INDEX);
   XFREE (VERTICES);
 
   XFREE (INDEX);
   XFREE (VERTICES);


@@ -190,16 +180,14 @@ set_state_table (void)
        state_table[i].lookaheads = count;
 
        if (rp
        state_table[i].lookaheads = count;
 
        if (rp

-           && (rp->nreds > 1
-               || (sp && !ISVAR (state_table[sp->shifts[0]].accessing_symbol))))
+           && (rp->nreds > 1 || (sp && SHIFT_IS_SHIFT (sp, 0))))

          count += rp->nreds;
        else
          state_table[i].consistent = 1;
 
        if (sp)
          for (k = 0; k < sp->nshifts; k++)
          count += rp->nreds;
        else
          state_table[i].consistent = 1;
 
        if (sp)
          for (k = 0; k < sp->nshifts; k++)

-           if (state_table[sp->shifts[k]].accessing_symbol
-               == error_token_number)
+           if (SHIFT_IS_ERROR (sp, k))

              {
                state_table[i].consistent = 0;
                break;
              {
                state_table[i].consistent = 0;
                break;


@@ -210,33 +198,6 @@ set_state_table (void)
 }
 
 
 }
 
 

-static void
-set_maxrhs (void)
-{
-  short *itemp;
-  int length;
-  int max;
-
-  length = 0;
-  max = 0;
-  for (itemp = ritem; *itemp; itemp++)
-    {
-      if (*itemp > 0)
-       {
-         length++;
-       }
-      else
-       {
-         if (length > max)
-           max = length;
-         length = 0;
-       }
-    }
-
-  maxrhs = max;
-}
-
-

 static void
 initialize_LA (void)
 {
 static void
 initialize_LA (void)
 {


@@ -279,13 +240,10 @@ set_goto_map (void)
   ngotos = 0;
   for (sp = first_shift; sp; sp = sp->next)
     {
   ngotos = 0;
   for (sp = first_shift; sp; sp = sp->next)
     {

-      for (i = sp->nshifts - 1; i >= 0; i--)
+      for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)

        {
          symbol = state_table[sp->shifts[i]].accessing_symbol;
 
        {
          symbol = state_table[sp->shifts[i]].accessing_symbol;
 

-         if (ISTOKEN (symbol))
-           break;
-

          if (ngotos == MAXSHORT)
            fatal (_("too many gotos (max %d)"), MAXSHORT);
 
          if (ngotos == MAXSHORT)
            fatal (_("too many gotos (max %d)"), MAXSHORT);
 


@@ -313,14 +271,11 @@ set_goto_map (void)
   for (sp = first_shift; sp; sp = sp->next)
     {
       state1 = sp->number;
   for (sp = first_shift; sp; sp = sp->next)
     {
       state1 = sp->number;

-      for (i = sp->nshifts - 1; i >= 0; i--)
+      for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)

        {
          state2 = sp->shifts[i];
          symbol = state_table[state2].accessing_symbol;
 
        {
          state2 = sp->shifts[i];
          symbol = state_table[state2].accessing_symbol;
 

-         if (ISTOKEN (symbol))
-           break;
-

          k = temp_map[symbol]++;
          from_state[k] = state1;
          to_state[k] = state2;
          k = temp_map[symbol]++;
          from_state[k] = state1;
          to_state[k] = state2;


@@ -368,73 +323,49 @@ map_goto (int state, int symbol)
 static void
 initialize_F (void)
 {
 static void
 initialize_F (void)
 {

-  int i;
-  int j;
-  int k;
-  shifts *sp;
-  short *edge;
-  unsigned *rowp;
-  short *rp;
-  short **reads;
-  int nedges;
-  int stateno;
-  int symbol;
-  int nwords;
+  short **reads = XCALLOC (short *, ngotos);
+  short *edge = XCALLOC (short, ngotos + 1);
+  int nedges = 0;

 
 

-  nwords = ngotos * tokensetsize;
-  F = XCALLOC (unsigned, nwords);
+  int i;

 
 

-  reads = XCALLOC (short *, ngotos);
-  edge = XCALLOC (short, ngotos + 1);
-  nedges = 0;
+  F = XCALLOC (unsigned, ngotos * tokensetsize);

 
 

-  rowp = F;

   for (i = 0; i < ngotos; i++)
     {
   for (i = 0; i < ngotos; i++)
     {

-      stateno = to_state[i];
-      sp = state_table[stateno].shift_table;
+      int stateno = to_state[i];
+      shifts *sp = state_table[stateno].shift_table;

 
       if (sp)
        {
 
       if (sp)
        {

-         k = sp->nshifts;
-
-         for (j = 0; j < k; j++)
+         int j;
+         for (j = 0; j < sp->nshifts && SHIFT_IS_SHIFT (sp, j); j++)

            {
            {

-             symbol = state_table[sp->shifts[j]].accessing_symbol;
-             if (ISVAR (symbol))
-               break;
-             SETBIT (rowp, symbol);
+             int symbol = state_table[sp->shifts[j]].accessing_symbol;
+             SETBIT (F + i * tokensetsize, symbol);

            }
 
            }
 

-         for (; j < k; j++)
+         for (; j < sp->nshifts; j++)

            {
            {

-             symbol = state_table[sp->shifts[j]].accessing_symbol;
+             int symbol = state_table[sp->shifts[j]].accessing_symbol;

              if (nullable[symbol])
                edge[nedges++] = map_goto (stateno, symbol);
            }
 
          if (nedges)
            {
              if (nullable[symbol])
                edge[nedges++] = map_goto (stateno, symbol);
            }
 
          if (nedges)
            {

-             reads[i] = rp = XCALLOC (short, nedges + 1);
-
-             for (j = 0; j < nedges; j++)
-               rp[j] = edge[j];
-
-             rp[nedges] = -1;
+             reads[i] = XCALLOC (short, nedges + 1);
+             shortcpy (reads[i], edge, nedges);
+             reads[i][nedges] = -1;

              nedges = 0;
            }
        }
              nedges = 0;
            }
        }

-
-      rowp += tokensetsize;

     }
 
   digraph (reads);
 
   for (i = 0; i < ngotos; i++)
     }
 
   digraph (reads);
 
   for (i = 0; i < ngotos; i++)

-    {
-      if (reads[i])
-       XFREE (reads[i]);
-    }
+    XFREE (reads[i]);

 
   XFREE (reads);
   XFREE (edge);
 
   XFREE (reads);
   XFREE (edge);


@@ -469,57 +400,88 @@ add_lookback_edge (int stateno, int ruleno, int gotono)
 }
 
 
 }
 
 

-static short **
-transpose (short **R_arg, int n)
+static void
+matrix_print (FILE *out, short **matrix, int n)

 {
 {

-  short **new_R;
-  short **temp_R;
-  short *nedges;
-  short *sp;
-  int i;
-  int k;
+  int i, j;
+
+  for (i = 0; i < n; ++i)
+    {
+      fprintf (out, "%3d: ", i);
+      if (matrix[i])
+       for (j = 0; matrix[i][j] != -1; ++j)
+         fprintf (out, "%3d ", matrix[i][j]);
+      fputc ('\n', out);
+    }
+  fputc ('\n', out);
+}

 
 

-  nedges = XCALLOC (short, n);
+/*-------------------------------------------------------------------.
+| Return the transpose of R_ARG, of size N.  Destroy R_ARG, as it is |
+| replaced with the result.                                          |
+|                                                                    |
+| R_ARG[I] is NULL or a -1 terminated list of numbers.               |
+|                                                                    |
+| RESULT[NUM] is NULL or the -1 terminated list of the I such as NUM |
+| is in R_ARG[I].                                                    |
+`-------------------------------------------------------------------*/

 
 

-  for (i = 0; i < n; i++)
+static short **
+transpose (short **R_arg, int n)
+{
+  /* The result. */
+  short **new_R = XCALLOC (short *, n);
+  /* END_R[I] -- next entry of NEW_R[I]. */
+  short **end_R = XCALLOC (short *, n);
+  /* NEDGES[I] -- total size of NEW_R[I]. */
+  short *nedges = XCALLOC (short, n);
+  int i, j;
+
+  if (trace_flag)

     {
     {

-      sp = R_arg[i];
-      if (sp)
-       {
-         while (*sp >= 0)
-           nedges[*sp++]++;
-       }
+      fputs ("transpose: input\n", stderr);
+      matrix_print (stderr, R_arg, n);

     }
 
     }
 

-  new_R = XCALLOC (short *, n);
-  temp_R = XCALLOC (short *, n);
+  /* Count. */
+  for (i = 0; i < n; i++)
+    if (R_arg[i])
+      for (j = 0; R_arg[i][j] >= 0; ++j)
+       ++nedges[R_arg[i][j]];

 
 

+  /* Allocate. */

   for (i = 0; i < n; i++)
   for (i = 0; i < n; i++)

-    {
-      k = nedges[i];
-      if (k > 0)
+    if (nedges[i] > 0)
+      {
+       short *sp = XCALLOC (short, nedges[i] + 1);
+       sp[nedges[i]] = -1;
+       new_R[i] = sp;
+       end_R[i] = sp;
+      }
+
+  /* Store. */
+  for (i = 0; i < n; i++)
+    if (R_arg[i])
+      for (j = 0; R_arg[i][j] >= 0; ++j)

        {
        {

-         sp = XCALLOC (short, k + 1);
-         new_R[i] = sp;
-         temp_R[i] = sp;
-         sp[k] = -1;
+         *end_R[R_arg[i][j]] = i;
+         ++end_R[R_arg[i][j]];

        }
        }

-    }

 
 

-  XFREE (nedges);
+  free (nedges);
+  free (end_R);

 
 

+  /* Free the input: it is replaced with the result. */

   for (i = 0; i < n; i++)
   for (i = 0; i < n; i++)

+    XFREE (R_arg[i]);
+  free (R_arg);
+
+  if (trace_flag)

     {
     {

-      sp = R_arg[i];
-      if (sp)
-       {
-         while (*sp >= 0)
-           *temp_R[*sp++]++ = i;
-       }
+      fputs ("transpose: output\n", stderr);
+      matrix_print (stderr, new_R, n);

     }
 
     }
 

-  XFREE (temp_R);
-

   return new_R;
 }
 
   return new_R;
 }
 


@@ -527,50 +489,35 @@ transpose (short **R_arg, int n)
 static void
 build_relations (void)
 {
 static void
 build_relations (void)
 {

+  short *edge = XCALLOC (short, ngotos + 1);
+  short *states = XCALLOC (short, ritem_longest_rhs () + 1);

   int i;
   int i;

-  int j;
-  int k;
-  short *rulep;
-  short *rp;
-  shifts *sp;
-  int length;
-  int nedges;
-  int done;
-  int state1;
-  int stateno;
-  int symbol1;
-  int symbol2;
-  short *shortp;
-  short *edge;
-  short *states;
-  short **new_includes;

 
   includes = XCALLOC (short *, ngotos);
 
   includes = XCALLOC (short *, ngotos);

-  edge = XCALLOC (short, ngotos + 1);
-  states = XCALLOC (short, maxrhs + 1);

 
   for (i = 0; i < ngotos; i++)
     {
 
   for (i = 0; i < ngotos; i++)
     {

-      nedges = 0;
-      state1 = from_state[i];
-      symbol1 = state_table[to_state[i]].accessing_symbol;
+      int nedges = 0;
+      int state1 = from_state[i];
+      int symbol1 = state_table[to_state[i]].accessing_symbol;
+      short *rulep;

 
       for (rulep = derives[symbol1]; *rulep > 0; rulep++)
        {
 
       for (rulep = derives[symbol1]; *rulep > 0; rulep++)
        {

-         length = 1;
+         int done;
+         int length = 1;
+         int stateno = state1;
+         short *rp;

          states[0] = state1;
          states[0] = state1;

-         stateno = state1;

 
 

-         for (rp = ritem + rrhs[*rulep]; *rp > 0; rp++)
+         for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++)

            {
            {

-             symbol2 = *rp;
-             sp = state_table[stateno].shift_table;
-             k = sp->nshifts;
-
-             for (j = 0; j < k; j++)
+             shifts *sp = state_table[stateno].shift_table;
+             int j;
+             for (j = 0; j < sp->nshifts; j++)

                {
                  stateno = sp->shifts[j];
                {
                  stateno = sp->shifts[j];

-                 if (state_table[stateno].accessing_symbol == symbol2)
+                 if (state_table[stateno].accessing_symbol == *rp)

                    break;
                }
 
                    break;
                }
 


@@ -599,25 +546,18 @@ build_relations (void)
 
       if (nedges)
        {
 
       if (nedges)
        {

-         includes[i] = shortp = XCALLOC (short, nedges + 1);
+         int j;
+         includes[i] = XCALLOC (short, nedges + 1);

          for (j = 0; j < nedges; j++)
          for (j = 0; j < nedges; j++)

-           shortp[j] = edge[j];
-         shortp[nedges] = -1;
+           includes[i][j] = edge[j];
+         includes[i][nedges] = -1;

        }
     }
 
        }
     }
 

-  new_includes = transpose (includes, ngotos);
-
-  for (i = 0; i < ngotos; i++)
-    if (includes[i])
-      XFREE (includes[i]);
-
-  XFREE (includes);
-
-  includes = new_includes;
-

   XFREE (edge);
   XFREE (states);
   XFREE (edge);
   XFREE (states);

+
+  includes = transpose (includes, ngotos);

 }
 
 
 }
 
 


@@ -630,10 +570,7 @@ compute_FOLLOWS (void)
   digraph (includes);
 
   for (i = 0; i < ngotos; i++)
   digraph (includes);
 
   for (i = 0; i < ngotos; i++)

-    {
-      if (includes[i])
-       XFREE (includes[i]);
-    }
+    XFREE (includes[i]);

 
   XFREE (includes);
 }
 
   XFREE (includes);
 }


@@ -643,34 +580,20 @@ static void
 compute_lookaheads (void)
 {
   int i;
 compute_lookaheads (void)
 {
   int i;

-  int n;
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;

   shorts *sp;
   shorts *sp;

-  shorts *sptmp;               /* JF */

 
   for (i = 0; i < state_table[nstates].lookaheads; i++)
 
   for (i = 0; i < state_table[nstates].lookaheads; i++)

-    {
-      fp3 = LA (i + 1);
-      for (sp = lookback[i]; sp; sp = sp->next)
-       {
-         fp1 = LA (i);
-         fp2 = F + tokensetsize * sp->value;
-         while (fp1 < fp3)
-           *fp1++ |= *fp2++;
-       }
-    }
+    for (sp = lookback[i]; sp; sp = sp->next)
+      {
+       int size = LA (i + 1) - LA (i);
+       int j;
+       for (j = 0; j < size; ++j)
+         LA (i)[j] |= F (sp->value)[j];
+      }

 
 

+  /* Free LOOKBACK. */

   for (i = 0; i < state_table[nstates].lookaheads; i++)
   for (i = 0; i < state_table[nstates].lookaheads; i++)

-    {
-      /* JF removed ref to freed storage */
-      for (sp = lookback[i]; sp; sp = sptmp)
-       {
-         sptmp = sp->next;
-         XFREE (sp);
-       }
-    }
+    LIST_FREE (shorts, lookback[i]);

 
   XFREE (lookback);
   XFREE (F);
 
   XFREE (lookback);
   XFREE (F);


@@ -683,7 +606,6 @@ lalr (void)
   tokensetsize = WORDSIZE (ntokens);
 
   set_state_table ();
   tokensetsize = WORDSIZE (ntokens);
 
   set_state_table ();

-  set_maxrhs ();

   initialize_LA ();
   set_goto_map ();
   initialize_F ();
   initialize_LA ();
   set_goto_map ();
   initialize_F ();