X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/4d4f699ca481fbb1d255ade0561ad6c7a89949ae..5449dd0f25f584ec596f165cb6004e1b4d092f10:/src/lalr.c

diff --git a/src/lalr.c b/src/lalr.c
index c2554dcf..0b269255 100644
--- a/src/lalr.c
+++ b/src/lalr.c
@@ -31,25 +31,22 @@
 #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.
    */
-state_t *state_table = NULL;
+state_t **state_table = NULL;
 
 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)
@@ -136,27 +142,33 @@ set_state_table (void)
   /* NSTATES + 1 because lookahead for the pseudo state number NSTATES
      might be used (see conflicts.c).  It is too opaque for me to
      provide a probably less hacky implementation. --akim */
-  state_table = XCALLOC (state_t, nstates + 1);
+  state_table = XCALLOC (state_t *, nstates + 1);
 
   {
-    core *sp;
+    state_t *sp;
     for (sp = first_state; sp; sp = sp->next)
-      {
-	state_table[sp->number].state = sp;
-	state_table[sp->number].accessing_symbol = sp->accessing_symbol;
-      }
+      state_table[sp->number] = sp;
   }
 
   {
     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 sure 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
@@ -168,60 +180,29 @@ 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;
+	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;
-	      }
-      }
-     state_table[nstates].lookaheads = count;
-  }
-}
-
+	  state_table[i]->consistent = 1;
 
-/*------------------------------------------.
-| 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;
-	}
-    }
+	for (k = 0; k < sp->nshifts; k++)
+	  if (SHIFT_IS_ERROR (sp, k))
+	    {
+	      state_table[i]->consistent = 0;
+	      break;
+	    }
+      }
 
-  return max;
+    /* Seems to be needed by conflicts.c. */
+    state_table[nstates] = STATE_ALLOC (0);
+    state_table[nstates]->lookaheads = count;
+  }
 }
 
 
@@ -233,7 +214,7 @@ initialize_LA (void)
   short *np;
   reductions *rp;
 
-  size_t nLA = state_table[nstates].lookaheads;
+  size_t nLA = state_table[nstates]->lookaheads;
   if (!nLA)
     nLA = 1;
 
@@ -243,8 +224,8 @@ initialize_LA (void)
 
   np = LAruleno;
   for (i = 0; i < nstates; i++)
-    if (!state_table[i].consistent)
-      if ((rp = state_table[i].reduction_table))
+    if (!state_table[i]->consistent)
+      if ((rp = state_table[i]->reductions))
 	for (j = 0; j < rp->nreds; j++)
 	  *np++ = rp->rules[j];
 }
@@ -266,21 +247,16 @@ set_goto_map (void)
 
   ngotos = 0;
   for (sp = first_shift; sp; sp = sp->next)
-    {
-      for (i = sp->nshifts - 1; i >= 0; i--)
-	{
-	  symbol = state_table[sp->shifts[i]].accessing_symbol;
-
-	  if (ISTOKEN (symbol))
-	    break;
+    for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)
+      {
+	symbol = state_table[sp->shifts[i]]->accessing_symbol;
 
-	  if (ngotos == MAXSHORT)
-	    fatal (_("too many gotos (max %d)"), MAXSHORT);
+	if (ngotos == MAXSHORT)
+	  fatal (_("too many gotos (max %d)"), MAXSHORT);
 
-	  ngotos++;
-	  goto_map[symbol]++;
-	}
-    }
+	ngotos++;
+	goto_map[symbol]++;
+      }
 
   k = 0;
   for (i = ntokens; i < nsyms; i++)
@@ -301,13 +277,10 @@ set_goto_map (void)
   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;
-
-	  if (ISTOKEN (symbol))
-	    break;
+	  symbol = state_table[state2]->accessing_symbol;
 
 	  k = temp_map[symbol]++;
 	  from_state[k] = state1;
@@ -367,33 +340,28 @@ 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;
 	}
     }
 
@@ -415,8 +383,8 @@ add_lookback_edge (int stateno, int ruleno, int gotono)
   int found;
   shorts *sp;
 
-  i = state_table[stateno].lookaheads;
-  k = state_table[stateno + 1].lookaheads;
+  i = state_table[stateno]->lookaheads;
+  k = state_table[stateno + 1]->lookaheads;
   found = 0;
   while (!found && i < k)
     {
@@ -435,50 +403,88 @@ 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;
-  int i;
+  int i, j;
 
-  nedges = XCALLOC (short, n);
+  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);
+}
 
-  for (i = 0; i < n; i++)
+/*-------------------------------------------------------------------.
+| 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)
+{
+  /* 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++)
+    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]];
+	}
+
+  free (nedges);
+  free (end_R);
 
+  /* Free the input: it is replaced with the result. */
   for (i = 0; i < n; i++)
+    XFREE (R_arg[i]);
+  free (R_arg);
+
+  if (trace_flag)
     {
-      short *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;
 }
 
@@ -486,51 +492,42 @@ transpose (short **R_arg, int n)
 static void
 build_relations (void)
 {
+  short *edge = XCALLOC (short, ngotos + 1);
+  short *states = XCALLOC (short, ritem_longest_rhs () + 1);
   int i;
-  int j;
-  short *rulep;
-  short *rp;
-  int nedges;
-  int done;
-  int state1;
-  int stateno;
-  int symbol1;
-  short *edge;
-  short *states;
-  short **new_includes;
 
   includes = XCALLOC (short *, ngotos);
-  edge = XCALLOC (short, ngotos + 1);
-  states = XCALLOC (short, maxrhs () + 1);
 
   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++)
 	{
+	  int done;
 	  int length = 1;
+	  int stateno = state1;
+	  short *rp;
 	  states[0] = state1;
-	  stateno = state1;
 
 	  for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++)
 	    {
-	      int symbol2 = *rp;
-	      shifts *sp = state_table[stateno].shift_table;
-
+	      shifts *sp = state_table[stateno]->shifts;
+	      int j;
 	      for (j = 0; j < sp->nshifts; j++)
 		{
 		  stateno = sp->shifts[j];
-		  if (state_table[stateno].accessing_symbol == symbol2)
+		  if (state_table[stateno]->accessing_symbol == *rp)
 		    break;
 		}
 
 	      states[length++] = stateno;
 	    }
 
-	  if (!state_table[stateno].consistent)
+	  if (!state_table[stateno]->consistent)
 	    add_lookback_edge (stateno, *rulep, i);
 
 	  length--;
@@ -552,6 +549,7 @@ build_relations (void)
 
       if (nedges)
 	{
+	  int j;
 	  includes[i] = XCALLOC (short, nedges + 1);
 	  for (j = 0; j < nedges; j++)
 	    includes[i][j] = edge[j];
@@ -559,16 +557,10 @@ build_relations (void)
 	}
     }
 
-  new_includes = transpose (includes, ngotos);
-
-  for (i = 0; i < ngotos; i++)
-    XFREE (includes[i]);
-  XFREE (includes);
-
-  includes = new_includes;
-
   XFREE (edge);
   XFREE (states);
+
+  includes = transpose (includes, ngotos);
 }
 
 
@@ -593,17 +585,17 @@ compute_lookaheads (void)
   int i;
   shorts *sp;
 
-  for (i = 0; i < state_table[nstates].lookaheads; i++)
+  for (i = 0; i < state_table[nstates]->lookaheads; i++)
     for (sp = lookback[i]; sp; sp = sp->next)
       {
-	unsigned *fp1 = LA (i);
-	unsigned *fp2 = F (sp->value);
-	while (fp1 < LA (i + 1))
-	  *fp1++ |= *fp2++;
+	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++)
     LIST_FREE (shorts, lookback[i]);
 
   XFREE (lookback);