#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;
+/* 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;
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;
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)
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);
-
- {
- core *sp;
- for (sp = first_state; sp; sp = sp->next)
- {
- state_table[sp->number].state = sp;
- state_table[sp->number].accessing_symbol = sp->accessing_symbol;
- }
- }
-
- {
- shifts *sp;
- for (sp = first_shift; sp; sp = sp->next)
- state_table[sp->number].shift_table = sp;
- }
-
- {
- reductions *rp;
- for (rp = first_reduction; rp; rp = rp->next)
- state_table[rp->number].reduction_table = rp;
- }
-
- /* 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].reduction_table;
- shifts *sp = state_table[i].shift_table;
-
- state_table[i].lookaheads = count;
-
- if (rp
- && (rp->nreds > 1
- || (sp && !ISVAR (state_table[sp->shifts[0]].accessing_symbol))))
- 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;
- }
-}
-
-
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;
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];
}
static void
set_goto_map (void)
{
- shifts *sp;
+ int state;
int i;
int symbol;
int k;
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 (state = 0; state < nstates; ++state)
{
- for (i = sp->nshifts - 1; i >= 0; i--)
+ shifts *sp = state_table[state]->shifts;
+ 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;
+ symbol = state_table[sp->shifts[i]]->accessing_symbol;
if (ngotos == MAXSHORT)
fatal (_("too many gotos (max %d)"), MAXSHORT);
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;
- for (i = sp->nshifts - 1; i >= 0; i--)
+ 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;
-
- if (ISTOKEN (symbol))
- break;
+ 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;
+ k = temp_map[symbol]++;
+ from_state[k] = state;
+ to_state[k] = state2;
+ }
}
}
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;
}
}
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
+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;
}
{
int nedges = 0;
int state1 = from_state[i];
- int symbol1 = state_table[to_state[i]].accessing_symbol;
+ int symbol1 = state_table[to_state[i]]->accessing_symbol;
short *rulep;
for (rulep = derives[symbol1]; *rulep > 0; rulep++)
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++)
{
stateno = sp->shifts[j];
- if (state_table[stateno].accessing_symbol == *rp)
+ 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--;
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 ();
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