void
flowrpo(Graph *g)
{
Flow *r1;
int32 i, d, me, nr, *idom;
Flow **rpo2r;
free(g->rpo);
g->rpo = calloc(g->num*sizeof g->rpo[0], 1);
idom = calloc(g->num*sizeof idom[0], 1);
if(g->rpo == nil || idom == nil)
fatal("out of memory");
for(r1 = g->start; r1 != nil; r1 = r1->link)
r1->active = 0;
rpo2r = g->rpo;
d = postorder(g->start, rpo2r, 0);
nr = g->num;
if(d > nr)
fatal("too many reg nodes %d %d", d, nr);
nr = d;
for(i = 0; i < nr / 2; i++) {
r1 = rpo2r[i];
rpo2r[i] = rpo2r[nr - 1 - i];
rpo2r[nr - 1 - i] = r1;
}
for(i = 0; i < nr; i++)
rpo2r[i]->rpo = i;
idom[0] = 0;
for(i = 0; i < nr; i++) {
r1 = rpo2r[i];
me = r1->rpo;
d = -1;
// rpo2r[r->rpo] == r protects against considering dead code,
// which has r->rpo == 0.
if(r1->p1 != nil && rpo2r[r1->p1->rpo] == r1->p1 && r1->p1->rpo < me)
d = r1->p1->rpo;
for(r1 = r1->p2; r1 != nil; r1 = r1->p2link)
if(rpo2r[r1->rpo] == r1 && r1->rpo < me)
d = rpolca(idom, d, r1->rpo);
idom[i] = d;
}
for(i = 0; i < nr; i++) {
r1 = rpo2r[i];
r1->loop++;
if(r1->p2 != nil && loophead(idom, r1))
loopmark(rpo2r, i, r1);
}
free(idom);
for(r1 = g->start; r1 != nil; r1 = r1->link)
r1->active = 0;
}
void
loopit(Reg *r, int32 nr)
{
Reg *r1;
int32 i, d, me;
if(nr > maxnr) {
rpo2r = mal(nr * sizeof(Reg*));
idom = mal(nr * sizeof(int32));
maxnr = nr;
}
d = postorder(r, rpo2r, 0);
if(d > nr)
fatal("too many reg nodes %d %d", d, nr);
nr = d;
for(i = 0; i < nr / 2; i++) {
r1 = rpo2r[i];
rpo2r[i] = rpo2r[nr - 1 - i];
rpo2r[nr - 1 - i] = r1;
}
for(i = 0; i < nr; i++)
rpo2r[i]->rpo = i;
idom[0] = 0;
for(i = 0; i < nr; i++) {
r1 = rpo2r[i];
me = r1->rpo;
d = -1;
// rpo2r[r->rpo] == r protects against considering dead code,
// which has r->rpo == 0.
if(r1->p1 != R && rpo2r[r1->p1->rpo] == r1->p1 && r1->p1->rpo < me)
d = r1->p1->rpo;
for(r1 = r1->p2; r1 != nil; r1 = r1->p2link)
if(rpo2r[r1->rpo] == r1 && r1->rpo < me)
d = rpolca(idom, d, r1->rpo);
idom[i] = d;
}
for(i = 0; i < nr; i++) {
r1 = rpo2r[i];
r1->loop++;
if(r1->p2 != R && loophead(idom, r1))
loopmark(rpo2r, i, r1);
}
}
void
loopit(Reg *r, int32_t nr)
{
Reg *r1;
int32_t i, d, me;
if(nr > maxnr) {
rpo2r = alloc(nr * sizeof(Reg*));
idom = alloc(nr * sizeof(int32_t));
maxnr = nr;
}
d = postorder(r, rpo2r, 0);
if(d > nr)
fatal(Z, "too many reg nodes");
nr = d;
for(i = 0; i < nr / 2; i++){
r1 = rpo2r[i];
rpo2r[i] = rpo2r[nr - 1 - i];
rpo2r[nr - 1 - i] = r1;
}
for(i = 0; i < nr; i++)
rpo2r[i]->rpo = i;
idom[0] = 0;
for(i = 0; i < nr; i++){
r1 = rpo2r[i];
me = r1->rpo;
d = -1;
if(r1->p1 != R && r1->p1->rpo < me)
d = r1->p1->rpo;
for(r1 = r1->p2; r1 != nil; r1 = r1->p2link)
if(r1->rpo < me)
d = rpolca(idom, d, r1->rpo);
idom[i] = d;
}
for(i = 0; i < nr; i++){
r1 = rpo2r[i];
r1->loop++;
if(r1->p2 != R && loophead(idom, r1))
loopmark(rpo2r, i, r1);
}
}
