#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. */
state_t **state_table = NULL;
int tokensetsize;
short *LAruleno;
unsigned *LA;
+size_t nLA;
static int ngotos;
short *goto_map;
break;
for (k = 0; k < size; ++k)
- F (i)[k] = F (j)[k];
+ F (j)[k] = F (i)[k];
}
}
}
-/*--------------------.
-| Build STATE_TABLE. |
-`--------------------*/
-
-static void
-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_t *sp;
- for (sp = first_state; sp; sp = sp->next)
- state_table[sp->number] = sp;
- }
-
- {
- shifts *sp;
- for (sp = first_shift; sp; sp = sp->next)
- state_table[sp->number]->shifts = sp;
- }
-
- {
- reductions *rp;
- for (rp = first_reduction; rp; rp = rp->next)
- 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
- performed after having set some of the other members which are
- used below. Change with extreme caution. */
- {
- int i;
- int count = 0;
- for (i = 0; i < nstates; i++)
- {
- int k;
- reductions *rp = state_table[i]->reductions;
- shifts *sp = state_table[i]->shifts;
-
- state_table[i]->lookaheads = count;
-
- if (rp
- && (rp->nreds > 1 || (sp->nshifts && SHIFT_IS_SHIFT (sp, 0))))
- count += rp->nreds;
- else
- state_table[i]->consistent = 1;
-
- for (k = 0; k < sp->nshifts; k++)
- if (SHIFT_IS_ERROR (sp, k))
- {
- state_table[i]->consistent = 0;
- break;
- }
- }
-
- /* Seems to be needed by conflicts.c. */
- state_table[nstates] = STATE_ALLOC (0);
- state_table[nstates]->lookaheads = count;
- }
-}
-
-
static void
initialize_LA (void)
{
short *np;
reductions *rp;
- size_t nLA = state_table[nstates]->lookaheads;
+ /* Avoid having to special case 0. */
if (!nLA)
nLA = 1;
static void
set_goto_map (void)
{
- shifts *sp;
- int i;
- int symbol;
- int k;
+ int state, i;
short *temp_map;
- int state2;
- int state1;
goto_map = XCALLOC (short, nvars + 1) - ntokens;
temp_map = XCALLOC (short, nvars + 1) - ntokens;
ngotos = 0;
- for (sp = first_shift; sp; sp = sp->next)
- 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);
+ for (state = 0; state < nstates; ++state)
+ {
+ shifts *sp = state_table[state]->shifts;
+ for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)
+ {
+ int symbol = state_table[sp->shifts[i]]->accessing_symbol;
- ngotos++;
- goto_map[symbol]++;
- }
+ if (ngotos == MAXSHORT)
+ fatal (_("too many gotos (max %d)"), MAXSHORT);
- k = 0;
- for (i = ntokens; i < nsyms; i++)
- {
- temp_map[i] = k;
- k += goto_map[i];
+ ngotos++;
+ goto_map[symbol]++;
+ }
}
- for (i = ntokens; i < nsyms; i++)
- goto_map[i] = temp_map[i];
+ {
+ int k = 0;
+ for (i = ntokens; i < nsyms; i++)
+ {
+ temp_map[i] = k;
+ k += goto_map[i];
+ }
+
+ for (i = ntokens; i < nsyms; i++)
+ goto_map[i] = temp_map[i];
- goto_map[nsyms] = ngotos;
- temp_map[nsyms] = ngotos;
+ goto_map[nsyms] = ngotos;
+ temp_map[nsyms] = ngotos;
+ }
from_state = XCALLOC (short, ngotos);
to_state = XCALLOC (short, ngotos);
- for (sp = first_shift; sp; sp = sp->next)
+ for (state = 0; state < nstates; ++state)
{
- state1 = sp->number;
+ shifts *sp = state_table[state]->shifts;
for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)
{
- state2 = sp->shifts[i];
- symbol = state_table[state2]->accessing_symbol;
+ int state2 = sp->shifts[i];
+ int symbol = state_table[state2]->accessing_symbol;
- k = temp_map[symbol]++;
- from_state[k] = state1;
+ int k = temp_map[symbol]++;
+ from_state[k] = state;
to_state[k] = state2;
}
}
add_lookback_edge (int stateno, int ruleno, int gotono)
{
int i;
- int k;
- int found;
shorts *sp;
- i = state_table[stateno]->lookaheads;
- k = state_table[stateno + 1]->lookaheads;
- found = 0;
- while (!found && i < k)
- {
- if (LAruleno[i] == ruleno)
- found = 1;
- else
- i++;
- }
+ for (i = 0; i < state_table[stateno]->nlookaheads; ++i)
+ if (LAruleno[state_table[stateno]->lookaheadsp + i] == ruleno)
+ break;
- assert (found);
+ assert (LAruleno[state_table[stateno]->lookaheadsp + i] == ruleno);
sp = XCALLOC (shorts, 1);
- sp->next = lookback[i];
+ sp->next = lookback[state_table[stateno]->lookaheadsp + i];
sp->value = gotono;
- lookback[i] = sp;
+ lookback[state_table[stateno]->lookaheadsp + i] = sp;
}
static void
compute_lookaheads (void)
{
- int i;
+ size_t i;
shorts *sp;
- for (i = 0; i < state_table[nstates]->lookaheads; i++)
+ for (i = 0; i < nLA; i++)
for (sp = lookback[i]; sp; sp = sp->next)
{
int size = LA (i + 1) - LA (i);
}
/* Free LOOKBACK. */
- for (i = 0; i < state_table[nstates]->lookaheads; i++)
+ for (i = 0; i < nLA; i++)
LIST_FREE (shorts, lookback[i]);
XFREE (lookback);
}
+/*--------------------------------------.
+| Initializing the lookaheads members. |
+`--------------------------------------*/
+
+static void
+initialize_lookaheads (void)
+{
+ int i;
+ nLA = 0;
+ for (i = 0; i < nstates; i++)
+ {
+ int k;
+ int nlookaheads = 0;
+ reductions *rp = state_table[i]->reductions;
+ shifts *sp = state_table[i]->shifts;
+
+ if (rp
+ && (rp->nreds > 1 || (sp->nshifts && SHIFT_IS_SHIFT (sp, 0))))
+ nlookaheads += rp->nreds;
+ else
+ state_table[i]->consistent = 1;
+
+ for (k = 0; k < sp->nshifts; k++)
+ if (SHIFT_IS_ERROR (sp, k))
+ {
+ state_table[i]->consistent = 0;
+ break;
+ }
+
+ state_table[i]->nlookaheads = nlookaheads;
+ state_table[i]->lookaheadsp = nLA;
+ nLA += nlookaheads;
+ }
+}
+
void
lalr (void)
{
tokensetsize = WORDSIZE (ntokens);
- set_state_table ();
+ initialize_lookaheads ();
initialize_LA ();
set_goto_map ();
initialize_F ();
projects / bison.git / blobdiff