/* 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.
The entry point is generate_states. */
#include "system.h"
+#include "getargs.h"
+#include "reader.h"
#include "gram.h"
#include "state.h"
#include "complain.h"
static short *shiftset = NULL;
static short **kernel_base = NULL;
-static short **kernel_end = NULL;
+static int *kernel_size = NULL;
static short *kernel_items = NULL;
/* hash table for states, to recognize equivalent ones. */
static void
allocate_itemsets (void)
{
- short *itemp = NULL;
- int symbol;
int i;
int 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
}
shift_symbol = symbol_count;
- kernel_end = XCALLOC (short *, nsyms);
+ kernel_size = XCALLOC (int, nsyms);
}
XFREE (redset);
XFREE (shiftset);
XFREE (kernel_base);
- XFREE (kernel_end);
+ XFREE (kernel_size);
XFREE (kernel_items);
XFREE (state_table);
}
| 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
{
int i;
int shiftcount;
- short *isp;
- short *ksp;
- int symbol;
-#if TRACE
- fprintf (stderr, "Entering new_itemsets, state = %d\n",
- this_state->number);
-#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 < itemsetsize; ++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]++;
}
}
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, state = %d\n",
- symbol, nstates);
-#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_ALLOC (n);
+ 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;
/*--------------------------------------------------------------.
| 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
- fprintf (stderr, "Entering get_state, symbol = %d\n", symbol);
-#endif
+ if (trace_flag)
+ fprintf (stderr, "Entering get_state, state = %d, symbol = %d (%s)\n",
+ this_state->number, symbol, tags[symbol]);
- 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])
{
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)
state_table[key] = sp = new_state (symbol);
}
+ if (trace_flag)
+ fprintf (stderr, "Exiting get_state => %d\n", sp->number);
+
return sp->number;
}
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 */
}
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_ALLOC (0);
- first_state = last_state = this_state = p;
+ first_state = last_state = this_state = CORE_ALLOC (0);
nstates = 1;
}
static void
save_shifts (void)
{
- shifts *p;
- short *sp1;
- short *sp2;
- short *send;
-
- p = SHIFTS_ALLOC (nshifts);
+ 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;
}
static void
save_reductions (void)
{
- short *isp;
- short *rp1;
- short *rp2;
- int item;
int count;
- reductions *p;
-
- short *rend;
+ int i;
/* Find and count the active items that represent ends of rules. */
count = 0;
- for (isp = itemset; isp < itemsetend; isp++)
+ for (i = 0; i < itemsetsize; ++i)
{
- item = ritem[*isp];
+ int item = ritem[itemset[i]];
if (item < 0)
redset[count++] = -item;
}
if (count)
{
- p = REDUCTIONS_ALLOC (count);
+ reductions *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;
}
}
projects / bison.git / blobdiff