X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/aa7815f5c6e8e07a85e47df9cd7b579468969efb..125ecb5684787648d54a799be962cc5c48098279:/src/LR0.c

diff --git a/src/LR0.c b/src/LR0.c
index b37594e6..cecc0eae 100644
--- a/src/LR0.c
+++ b/src/LR0.c
@@ -1,5 +1,5 @@
 /* Generate the nondeterministic finite state machine 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.
 
@@ -23,7 +23,8 @@
    The entry point is generate_states.  */
 
 #include "system.h"
-#include "xalloc.h"
+#include "getargs.h"
+#include "reader.h"
 #include "gram.h"
 #include "state.h"
 #include "complain.h"
@@ -33,54 +34,47 @@
 
 int nstates;
 int final_state;
-core *first_state;
-shifts *first_shift;
-reductions *first_reduction;
+core *first_state = NULL;
+shifts *first_shift = NULL;
+reductions *first_reduction = NULL;
 
-static core *this_state;
-static core *last_state;
-static shifts *last_shift;
-static reductions *last_reduction;
+static core *this_state = NULL;
+static core *last_state = NULL;
+static shifts *last_shift = NULL;
+static reductions *last_reduction = NULL;
 
 static int nshifts;
-static short *shift_symbol;
+static short *shift_symbol = NULL;
 
-static short *redset;
-static short *shiftset;
+static short *redset = NULL;
+static short *shiftset = NULL;
 
-static short **kernel_base;
-static short **kernel_end;
-static short *kernel_items;
+static short **kernel_base = NULL;
+static size_t *kernel_size = NULL;
+static short *kernel_items = NULL;
 
 /* hash table for states, to recognize equivalent ones.  */
 
 #define	STATE_TABLE_SIZE	1009
-static core **state_table;
+static core **state_table = NULL;
 
 
 static void
 allocate_itemsets (void)
 {
-  short *itemp;
-  int symbol;
   int i;
   int count;
-  short *symbol_count;
+  short *symbol_count = NULL;
 
   count = 0;
   symbol_count = XCALLOC (short, nsyms);
 
-  itemp = ritem;
-  symbol = *itemp++;
-  while (symbol)
-    {
-      if (symbol > 0)
-	{
-	  count++;
-	  symbol_count[symbol]++;
-	}
-      symbol = *itemp++;
-    }
+  for (i = 0; ritem[i]; ++i)
+    if (ritem[i] > 0)
+      {
+	count++;
+	symbol_count[ritem[i]]++;
+      }
 
   /* See comments before new_itemsets.  All the vectors of items
      live inside KERNEL_ITEMS.  The number of active items after
@@ -89,7 +83,8 @@ allocate_itemsets (void)
      We allocate that much space for each symbol.  */
 
   kernel_base = XCALLOC (short *, nsyms);
-  kernel_items = XCALLOC (short, count);
+  if (count)
+    kernel_items = XCALLOC (short, count);
 
   count = 0;
   for (i = 0; i < nsyms; i++)
@@ -99,7 +94,7 @@ allocate_itemsets (void)
     }
 
   shift_symbol = symbol_count;
-  kernel_end = XCALLOC (short *, nsyms);
+  kernel_size = XCALLOC (size_t, nsyms);
 }
 
 
@@ -121,7 +116,7 @@ free_storage (void)
   XFREE (redset);
   XFREE (shiftset);
   XFREE (kernel_base);
-  XFREE (kernel_end);
+  XFREE (kernel_size);
   XFREE (kernel_items);
   XFREE (state_table);
 }
@@ -137,8 +132,7 @@ free_storage (void)
 | shift_symbol is set to a vector of the symbols that can be      |
 | shifted.  For each symbol in the grammar, kernel_base[symbol]   |
 | points to a vector of item numbers activated if that symbol is  |
-| shifted, and kernel_end[symbol] points after the end of that    |
-| vector.                                                         |
+| shifted, and kernel_size[symbol] is their numbers.              |
 `----------------------------------------------------------------*/
 
 static void
@@ -146,37 +140,29 @@ new_itemsets (void)
 {
   int i;
   int shiftcount;
-  short *isp;
-  short *ksp;
-  int symbol;
 
-#if TRACE
-  fprintf (stderr, "Entering new_itemsets\n");
-#endif
+  if (trace_flag)
+    fprintf (stderr, "Entering new_itemsets, state = %d\n",
+	     this_state->number);
 
   for (i = 0; i < nsyms; i++)
-    kernel_end[i] = NULL;
+    kernel_size[i] = 0;
 
   shiftcount = 0;
 
-  isp = itemset;
-
-  while (isp < itemsetend)
+  for (i = 0; i < itemsetend - itemset; ++i)
     {
-      i = *isp++;
-      symbol = ritem[i];
+      int symbol = ritem[itemset[i]];
       if (symbol > 0)
 	{
-	  ksp = kernel_end[symbol];
-
-	  if (!ksp)
+	  if (!kernel_size[symbol])
 	    {
-	      shift_symbol[shiftcount++] = symbol;
-	      ksp = kernel_base[symbol];
+	      shift_symbol[shiftcount] = symbol;
+	      shiftcount++;
 	    }
 
-	  *ksp++ = i + 1;
-	  kernel_end[symbol] = ksp;
+	  kernel_base[symbol][kernel_size[symbol]] = itemset[i] + 1;
+	  kernel_size[symbol]++;
 	}
     }
 
@@ -193,36 +179,24 @@ new_itemsets (void)
 static core *
 new_state (int symbol)
 {
-  int n;
   core *p;
-  short *isp1;
-  short *isp2;
-  short *iend;
 
-#if TRACE
-  fprintf (stderr, "Entering new_state, symbol = %d\n", symbol);
-#endif
+  if (trace_flag)
+    fprintf (stderr, "Entering new_state, state = %d, symbol = %d (%s)\n",
+	     this_state->number, symbol, tags[symbol]);
 
   if (nstates >= MAXSHORT)
     fatal (_("too many states (max %d)"), MAXSHORT);
 
-  isp1 = kernel_base[symbol];
-  iend = kernel_end[symbol];
-  n = iend - isp1;
-
-  p =
-    (core *) xcalloc ((unsigned) (sizeof (core) + (n - 1) * sizeof (short)), 1);
+  p = CORE_ALLOC (kernel_size[symbol]);
   p->accessing_symbol = symbol;
   p->number = nstates;
-  p->nitems = n;
+  p->nitems = kernel_size[symbol];
 
-  isp2 = p->items;
-  while (isp1 < iend)
-    *isp2++ = *isp1++;
+  shortcpy (p->items, kernel_base[symbol], kernel_size[symbol]);
 
   last_state->next = p;
   last_state = p;
-
   nstates++;
 
   return p;
@@ -232,54 +206,41 @@ new_state (int symbol)
 /*--------------------------------------------------------------.
 | Find the state number for the state we would get to (from the |
 | current state) by shifting symbol.  Create a new state if no  |
-| equivalent one exists already.  Used by append_states.         |
+| equivalent one exists already.  Used by append_states.        |
 `--------------------------------------------------------------*/
 
 static int
 get_state (int symbol)
 {
   int key;
-  short *isp1;
   short *isp2;
-  short *iend;
+  int i;
   core *sp;
-  int found;
 
-  int n;
+  if (trace_flag)
+    fprintf (stderr, "Entering get_state, state = %d, symbol = %d (%s)\n",
+	     this_state->number, symbol, tags[symbol]);
 
-#if TRACE
-  fprintf (stderr, "Entering get_state, symbol = %d\n", symbol);
-#endif
-
-  isp1 = kernel_base[symbol];
-  iend = kernel_end[symbol];
-  n = iend - isp1;
-
-  /* add up the target state's active item numbers to get a hash key */
+  /* Add up the target state's active item numbers to get a hash key.
+     */
   key = 0;
-  while (isp1 < iend)
-    key += *isp1++;
-
+  for (i = 0; i < kernel_size[symbol]; ++i)
+    key += kernel_base[symbol][i];
   key = key % STATE_TABLE_SIZE;
-
   sp = state_table[key];
 
   if (sp)
     {
-      found = 0;
+      int found = 0;
       while (!found)
 	{
-	  if (sp->nitems == n)
+	  if (sp->nitems == kernel_size[symbol])
 	    {
+	      int i;
 	      found = 1;
-	      isp1 = kernel_base[symbol];
-	      isp2 = sp->items;
-
-	      while (found && isp1 < iend)
-		{
-		  if (*isp1++ != *isp2++)
-		    found = 0;
-		}
+	      for (i = 0; i < kernel_size[symbol]; ++i)
+		if (kernel_base[symbol][i] != sp->items[i])
+		  found = 0;
 	    }
 
 	  if (!found)
@@ -301,6 +262,9 @@ get_state (int symbol)
       state_table[key] = sp = new_state (symbol);
     }
 
+  if (trace_flag)
+    fprintf (stderr, "Exiting get_state => %d\n", sp->number);
+
   return sp->number;
 }
 
@@ -318,9 +282,9 @@ append_states (void)
   int j;
   int symbol;
 
-#if TRACE
-  fprintf (stderr, "Entering append_states\n");
-#endif
+  if (trace_flag)
+    fprintf (stderr, "Entering append_states, state = %d\n",
+	     this_state->number);
 
   /* first sort shift_symbol into increasing order */
 
@@ -337,20 +301,14 @@ append_states (void)
     }
 
   for (i = 0; i < nshifts; i++)
-    {
-      symbol = shift_symbol[i];
-      shiftset[i] = get_state (symbol);
-    }
+    shiftset[i] = get_state (shift_symbol[i]);
 }
 
 
 static void
 new_states (void)
 {
-  core *p;
-
-  p = (core *) xcalloc ((unsigned) (sizeof (core) - sizeof (short)), 1);
-  first_state = last_state = this_state = p;
+  first_state = last_state = this_state = CORE_ALLOC (0);
   nstates = 1;
 }
 
@@ -358,34 +316,18 @@ new_states (void)
 static void
 save_shifts (void)
 {
-  shifts *p;
-  short *sp1;
-  short *sp2;
-  short *send;
-
-  p = (shifts *) xcalloc ((unsigned) (sizeof (shifts) +
-				      (nshifts - 1) * sizeof (short)), 1);
+  shifts *p = SHIFTS_ALLOC (nshifts);
 
   p->number = this_state->number;
   p->nshifts = nshifts;
 
-  sp1 = shiftset;
-  sp2 = p->shifts;
-  send = shiftset + nshifts;
-
-  while (sp1 < send)
-    *sp2++ = *sp1++;
+  shortcpy (p->shifts, shiftset, nshifts);
 
   if (last_shift)
-    {
-      last_shift->next = p;
-      last_shift = p;
-    }
+    last_shift->next = p;
   else
-    {
-      first_shift = p;
-      last_shift = p;
-    }
+    first_shift = p;
+  last_shift = p;
 }
 
 
@@ -400,7 +342,7 @@ insert_start_shift (void)
   core *statep;
   shifts *sp;
 
-  statep = (core *) xcalloc ((unsigned) (sizeof (core) - sizeof (short)), 1);
+  statep = CORE_ALLOC (0);
   statep->number = nstates;
   statep->accessing_symbol = start_symbol;
 
@@ -408,7 +350,7 @@ insert_start_shift (void)
   last_state = statep;
 
   /* Make a shift from this state to (what will be) the final state.  */
-  sp = XCALLOC (shifts, 1);
+  sp = SHIFTS_ALLOC (1);
   sp->number = nstates++;
   sp->nshifts = 1;
   sp->shifts[0] = nstates;
@@ -465,10 +407,7 @@ augment_automaton (void)
 
 	      if (sp && sp->number == k)
 		{
-		  sp2 = (shifts *) xcalloc ((unsigned) (sizeof (shifts)
-							+
-							sp->nshifts *
-							sizeof (short)), 1);
+		  sp2 = SHIFTS_ALLOC (sp->nshifts + 1);
 		  sp2->number = k;
 		  sp2->nshifts = sp->nshifts + 1;
 		  sp2->shifts[0] = nstates;
@@ -485,7 +424,7 @@ augment_automaton (void)
 		}
 	      else
 		{
-		  sp2 = XCALLOC (shifts, 1);
+		  sp2 = SHIFTS_ALLOC (1);
 		  sp2->number = k;
 		  sp2->nshifts = 1;
 		  sp2->shifts[0] = nstates;
@@ -504,8 +443,7 @@ augment_automaton (void)
 	         going to the next-to-final state (yet to be made).  */
 	      sp = first_shift;
 
-	      sp2 = (shifts *) xcalloc (sizeof (shifts)
-					+ sp->nshifts * sizeof (short), 1);
+	      sp2 = SHIFTS_ALLOC (sp->nshifts + 1);
 	      sp2->nshifts = sp->nshifts + 1;
 
 	      /* Stick this shift into the vector at the proper place.  */
@@ -538,7 +476,7 @@ augment_automaton (void)
 	{
 	  /* The initial state didn't even have any shifts.
 	     Give it one shift, to the next-to-final state.  */
-	  sp = XCALLOC (shifts, 1);
+	  sp = SHIFTS_ALLOC (1);
 	  sp->nshifts = 1;
 	  sp->shifts[0] = nstates;
 
@@ -556,7 +494,7 @@ augment_automaton (void)
       /* There are no shifts for any state.
          Make one shift, from the initial state to the next-to-final state.  */
 
-      sp = XCALLOC (shifts, 1);
+      sp = SHIFTS_ALLOC (1);
       sp->nshifts = 1;
       sp->shifts[0] = nstates;
 
@@ -572,13 +510,13 @@ augment_automaton (void)
   /* Make the final state--the one that follows a shift from the
      next-to-final state.
      The symbol for that shift is 0 (end-of-file).  */
-  statep = (core *) xcalloc ((unsigned) (sizeof (core) - sizeof (short)), 1);
+  statep = CORE_ALLOC (0);
   statep->number = nstates;
   last_state->next = statep;
   last_state = statep;
 
   /* Make the shift from the final state to the termination state.  */
-  sp = XCALLOC (shifts, 1);
+  sp = SHIFTS_ALLOC (1);
   sp->number = nstates++;
   sp->nshifts = 1;
   sp->shifts[0] = nstates;
@@ -590,7 +528,7 @@ augment_automaton (void)
   final_state = nstates;
 
   /* Make the termination state.  */
-  statep = (core *) xcalloc ((unsigned) (sizeof (core) - sizeof (short)), 1);
+  statep = CORE_ALLOC (0);
   statep->number = nstates++;
   last_state->next = statep;
   last_state = statep;
@@ -607,8 +545,6 @@ static void
 save_reductions (void)
 {
   short *isp;
-  short *rp1;
-  short *rp2;
   int item;
   int count;
   reductions *p;
@@ -629,29 +565,18 @@ save_reductions (void)
 
   if (count)
     {
-      p = (reductions *) xcalloc ((unsigned) (sizeof (reductions) +
-					      (count - 1) * sizeof (short)), 1);
+      p = REDUCTIONS_ALLOC (count);
 
       p->number = this_state->number;
       p->nreds = count;
 
-      rp1 = redset;
-      rp2 = p->rules;
-      rend = rp1 + count;
-
-      for (/* nothing */; rp1 < rend; ++rp1, ++rp2)
-	*rp2 = *rp1;
+      shortcpy (p->rules, redset, count);
 
       if (last_reduction)
-	{
-	  last_reduction->next = p;
-	  last_reduction = p;
-	}
+	last_reduction->next = p;
       else
-	{
-	  first_reduction = p;
-	  last_reduction = p;
-	}
+	first_reduction = p;
+      last_reduction = p;
     }
 }