mirror of
https://github.com/python/cpython
synced 2024-10-14 15:42:19 +00:00
102 lines
1.8 KiB
C
102 lines
1.8 KiB
C
/* Parser accelerator module */
|
|
|
|
#include <stdio.h>
|
|
|
|
#include "PROTO.h"
|
|
#include "grammar.h"
|
|
#include "token.h"
|
|
#include "malloc.h"
|
|
|
|
static void
|
|
fixstate(g, d, s)
|
|
grammar *g;
|
|
dfa *d;
|
|
state *s;
|
|
{
|
|
arc *a;
|
|
int k;
|
|
int *accel;
|
|
int nl = g->g_ll.ll_nlabels;
|
|
s->s_accept = 0;
|
|
accel = NEW(int, nl);
|
|
for (k = 0; k < nl; k++)
|
|
accel[k] = -1;
|
|
a = s->s_arc;
|
|
for (k = s->s_narcs; --k >= 0; a++) {
|
|
int lbl = a->a_lbl;
|
|
label *l = &g->g_ll.ll_label[lbl];
|
|
int type = l->lb_type;
|
|
if (a->a_arrow >= (1 << 7)) {
|
|
printf("XXX too many states!\n");
|
|
continue;
|
|
}
|
|
if (ISNONTERMINAL(type)) {
|
|
dfa *d1 = finddfa(g, type);
|
|
int ibit;
|
|
if (type - NT_OFFSET >= (1 << 7)) {
|
|
printf("XXX too high nonterminal number!\n");
|
|
continue;
|
|
}
|
|
for (ibit = 0; ibit < g->g_ll.ll_nlabels; ibit++) {
|
|
if (testbit(d1->d_first, ibit)) {
|
|
if (accel[ibit] != -1)
|
|
printf("XXX ambiguity!\n");
|
|
accel[ibit] = a->a_arrow | (1 << 7) |
|
|
((type - NT_OFFSET) << 8);
|
|
}
|
|
}
|
|
}
|
|
else if (lbl == EMPTY)
|
|
s->s_accept = 1;
|
|
else if (lbl >= 0 && lbl < nl)
|
|
accel[lbl] = a->a_arrow;
|
|
}
|
|
while (nl > 0 && accel[nl-1] == -1)
|
|
nl--;
|
|
for (k = 0; k < nl && accel[k] == -1;)
|
|
k++;
|
|
if (k < nl) {
|
|
int i;
|
|
s->s_accel = NEW(int, nl-k);
|
|
if (s->s_accel == NULL) {
|
|
fprintf(stderr, "no mem to add parser accelerators\n");
|
|
exit(1);
|
|
}
|
|
s->s_lower = k;
|
|
s->s_upper = nl;
|
|
for (i = 0; k < nl; i++, k++)
|
|
s->s_accel[i] = accel[k];
|
|
}
|
|
DEL(accel);
|
|
}
|
|
|
|
static void
|
|
fixdfa(g, d)
|
|
grammar *g;
|
|
dfa *d;
|
|
{
|
|
state *s;
|
|
int j;
|
|
s = d->d_state;
|
|
for (j = 0; j < d->d_nstates; j++, s++)
|
|
fixstate(g, d, s);
|
|
}
|
|
|
|
void
|
|
addaccelerators(g)
|
|
grammar *g;
|
|
{
|
|
dfa *d;
|
|
int i;
|
|
#ifdef DEBUG
|
|
printf("Adding parser accellerators ...\n");
|
|
#endif
|
|
d = g->g_dfa;
|
|
for (i = g->g_ndfas; --i >= 0; d++)
|
|
fixdfa(g, d);
|
|
g->g_accel = 1;
|
|
#ifdef DEBUG
|
|
printf("Done.\n");
|
|
#endif
|
|
}
|