X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/4cecb5a2481ba9f3b254928ba705299b1548d09c..e89a22bfab22e4d2ee73be49dcb66b51f8d0e892:/src/lalr.c

diff --git a/src/lalr.c b/src/lalr.c
index ad2623d6..d05d4ff5 100644
--- a/src/lalr.c
+++ b/src/lalr.c
@@ -31,6 +31,7 @@
 #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.
@@ -41,15 +42,11 @@ int tokensetsize;
 short *LAruleno;
 unsigned *LA;
 
+static int ngotos;
 short *goto_map;
 short *from_state;
 short *to_state;
 
-extern void berror PARAMS ((const char *));
-
-static int infinity;
-static int ngotos;
-
 /* And for the famous F variable, which name is so descriptive that a
    comment is hardly needed.  <grin>.  */
 static unsigned *F = NULL;
@@ -57,11 +54,20 @@ static unsigned *F = NULL;
 
 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 int infinity;
 
 static void
 traverse (int i)
@@ -97,7 +103,7 @@ traverse (int i)
 	  break;
 
 	for (k = 0; k < size; ++k)
-	  F (i)[k] = F (j)[k];
+	  F (j)[k] = F (i)[k];
       }
 }
 
@@ -150,13 +156,22 @@ set_state_table (void)
   {
     shifts *sp;
     for (sp = first_shift; sp; sp = sp->next)
-      state_table[sp->number].shift_table = sp;
+      state_table[sp->number].shifts = sp;
   }
 
   {
     reductions *rp;
     for (rp = first_reduction; rp; rp = rp->next)
-      state_table[rp->number].reduction_table = rp;
+      state_table[rp->number].reductions = rp;
+  }
+
+  /* Pessimization, but simplification of the code: make sense all the
+     states have a shifts, even if reduced to 0 shifts.  */
+  {
+    int i;
+    for (i = 0; i < nstates; i++)
+      if (!state_table[i].shifts)
+	state_table[i].shifts = shifts_new (0);
   }
 
   /* Initializing the lookaheads members.  Please note that it must be
@@ -168,63 +183,29 @@ set_state_table (void)
     for (i = 0; i < nstates; i++)
       {
 	int k;
-	reductions *rp = state_table[i].reduction_table;
-	shifts *sp = state_table[i].shift_table;
+	reductions *rp = state_table[i].reductions;
+	shifts *sp = state_table[i].shifts;
 
 	state_table[i].lookaheads = count;
 
 	if (rp
-	    && (rp->nreds > 1
-		|| (sp && !ISVAR (state_table[sp->shifts[0]].accessing_symbol))))
+	    && (rp->nreds > 1 || (sp->nshifts && SHIFT_IS_SHIFT (sp, 0))))
 	  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)
-	      {
-		state_table[i].consistent = 0;
-		break;
-	      }
+	for (k = 0; k < sp->nshifts; k++)
+	  if (SHIFT_IS_ERROR (sp, k))
+	    {
+	      state_table[i].consistent = 0;
+	      break;
+	    }
       }
      state_table[nstates].lookaheads = count;
   }
 }
 
 
-/*------------------------------------------.
-| Return the size of the longest rule RHS.  |
-`------------------------------------------*/
-
-static size_t
-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;
-	}
-    }
-
-  return max;
-}
-
-
 static void
 initialize_LA (void)
 {
@@ -244,7 +225,7 @@ initialize_LA (void)
   np = LAruleno;
   for (i = 0; i < nstates; i++)
     if (!state_table[i].consistent)
-      if ((rp = state_table[i].reduction_table))
+      if ((rp = state_table[i].reductions))
 	for (j = 0; j < rp->nreds; j++)
 	  *np++ = rp->rules[j];
 }
@@ -266,21 +247,17 @@ set_goto_map (void)
 
   ngotos = 0;
   for (sp = first_shift; sp; sp = sp->next)
-    {
-      for (i = sp->nshifts - 1; i >= 0; i--)
+    if (sp->nshifts)
+      for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)
 	{
 	  symbol = state_table[sp->shifts[i]].accessing_symbol;
 
-	  if (ISTOKEN (symbol))
-	    break;
-
 	  if (ngotos == MAXSHORT)
 	    fatal (_("too many gotos (max %d)"), MAXSHORT);
 
 	  ngotos++;
 	  goto_map[symbol]++;
 	}
-    }
 
   k = 0;
   for (i = ntokens; i < nsyms; i++)
@@ -301,18 +278,16 @@ set_goto_map (void)
   for (sp = first_shift; sp; sp = sp->next)
     {
       state1 = sp->number;
-      for (i = sp->nshifts - 1; i >= 0; i--)
-	{
-	  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;
-	}
+      if (sp->nshifts)
+	for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)
+	  {
+	    state2 = sp->shifts[i];
+	    symbol = state_table[state2].accessing_symbol;
+
+	    k = temp_map[symbol]++;
+	    from_state[k] = state1;
+	    to_state[k] = state2;
+	  }
     }
 
   XFREE (temp_map + ntokens);
@@ -367,33 +342,28 @@ initialize_F (void)
   for (i = 0; i < ngotos; i++)
     {
       int stateno = to_state[i];
-      shifts *sp = state_table[stateno].shift_table;
+      shifts *sp = state_table[stateno].shifts;
 
-      if (sp)
+      int j;
+      for (j = 0; j < sp->nshifts && SHIFT_IS_SHIFT (sp, j); j++)
 	{
-	  int j;
-	  for (j = 0; j < sp->nshifts; j++)
-	    {
-	      int symbol = state_table[sp->shifts[j]].accessing_symbol;
-	      if (ISVAR (symbol))
-		break;
-	      SETBIT (F + i * tokensetsize, symbol);
-	    }
+	  int symbol = state_table[sp->shifts[j]].accessing_symbol;
+	  SETBIT (F (i), symbol);
+	}
 
-	  for (; j < sp->nshifts; j++)
-	    {
-	      int symbol = state_table[sp->shifts[j]].accessing_symbol;
-	      if (nullable[symbol])
-		edge[nedges++] = map_goto (stateno, symbol);
-	    }
+      for (; j < sp->nshifts; j++)
+	{
+	  int symbol = state_table[sp->shifts[j]].accessing_symbol;
+	  if (nullable[symbol])
+	    edge[nedges++] = map_goto (stateno, symbol);
+	}
 
-	  if (nedges)
-	    {
-	      reads[i] = XCALLOC (short, nedges + 1);
-	      shortcpy (reads[i], edge, nedges);
-	      reads[i][nedges] = -1;
-	      nedges = 0;
-	    }
+      if (nedges)
+	{
+	  reads[i] = XCALLOC (short, nedges + 1);
+	  shortcpy (reads[i], edge, nedges);
+	  reads[i][nedges] = -1;
+	  nedges = 0;
 	}
     }
 
@@ -435,59 +405,87 @@ add_lookback_edge (int stateno, int ruleno, int gotono)
 }
 
 
+static void
+matrix_print (FILE *out, short **matrix, int n)
+{
+  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);
+}
+
 /*-------------------------------------------------------------------.
 | 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].                                                    |
 `-------------------------------------------------------------------*/
 
 static short **
 transpose (short **R_arg, int n)
 {
-  short **new_R;
-  short **temp_R;
-  short *nedges;
-  int i;
-
-  nedges = XCALLOC (short, n);
-
-  for (i = 0; i < n; i++)
+  /* 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)
     {
-      short *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++)
     if (nedges[i] > 0)
       {
 	short *sp = XCALLOC (short, nedges[i] + 1);
-	new_R[i] = sp;
-	temp_R[i] = sp;
 	sp[nedges[i]] = -1;
+	new_R[i] = sp;
+	end_R[i] = sp;
       }
 
-  XFREE (nedges);
-
+  /* Store. */
   for (i = 0; i < n; i++)
-    {
-      short *sp = R_arg[i];
-      if (sp)
-	while (*sp >= 0)
-	  *temp_R[*sp++]++ = i;
-    }
+    if (R_arg[i])
+      for (j = 0; R_arg[i][j] >= 0; ++j)
+	{
+	  *end_R[R_arg[i][j]] = i;
+	  ++end_R[R_arg[i][j]];
+	}
 
-  XFREE (temp_R);
+  free (nedges);
+  free (end_R);
 
   /* Free the input: it is replaced with the result. */
   for (i = 0; i < n; i++)
     XFREE (R_arg[i]);
-  XFREE (R_arg);
+  free (R_arg);
+
+  if (trace_flag)
+    {
+      fputs ("transpose: output\n", stderr);
+      matrix_print (stderr, new_R, n);
+    }
 
   return new_R;
 }
@@ -497,7 +495,7 @@ static void
 build_relations (void)
 {
   short *edge = XCALLOC (short, ngotos + 1);
-  short *states = XCALLOC (short, maxrhs () + 1);
+  short *states = XCALLOC (short, ritem_longest_rhs () + 1);
   int i;
 
   includes = XCALLOC (short *, ngotos);
@@ -519,7 +517,7 @@ build_relations (void)
 
 	  for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++)
 	    {
-	      shifts *sp = state_table[stateno].shift_table;
+	      shifts *sp = state_table[stateno].shifts;
 	      int j;
 	      for (j = 0; j < sp->nshifts; j++)
 		{