static void checkreach(Cfg *cfg)
{
Bitset *reach, *kill;
size_t i, j, k;
Reaching *r;
Node *n, *m;
Bb *bb;
r = reaching(cfg);
// dumpcfg(cfg, stdout);
for (i = 0; i < cfg->nbb; i++) {
bb = cfg->bb[i];
if (!bb)
continue;
reach = bsdup(r->in[i]);
kill = mkbs();
for (j = 0; j < bb->nnl; j++) {
n = bb->nl[j];
if (exprop(n) == Oundef) {
bsput(reach, n->nid);
} else {
m = assignee(n);
if (m)
for (k = 0; k < r->ndefs[m->expr.did]; k++)
bsput(kill, r->defs[m->expr.did][k]);
checkundef(n, r, reach, kill);
}
}
bsfree(reach);
bsfree(kill);
}
}
static void genkill(Bb *bb, size_t **defs, size_t *ndefs, Bitset *gen, Bitset *kill)
{
size_t i, j, did;
Node *n;
for (i = 0; i < bb->nnl; i++) {
n = assignee(bb->nl[i]);
if (!n)
continue;
did = n->expr.did;
for (j = 0; j < ndefs[did]; j++) {
bsput(kill, defs[did][j]);
bsdel(gen, defs[did][j]);
}
bsput(gen, bb->nl[i]->nid);
bsdel(kill, bb->nl[i]->nid);
}
}
static void collectdefs(Cfg *cfg, size_t **defs, size_t *ndefs)
{
size_t i, j, did;
Node *n;
Bb *bb;
for (i = 0; i < cfg->nbb; i++) {
bb = cfg->bb[i];
if (!bb)
continue;
for (j = 0; j < bb->nnl; j++) {
n = assignee(bb->nl[j]);
if (n && exprop(n) == Ovar) {
did = n->expr.did;
ndefs[did]++;
defs[did] = xrealloc(defs[did], ndefs[did] * sizeof(size_t));
defs[did][ndefs[did] - 1] = bb->nl[j]->nid;
}
}
}
}