void
pic_wind(pic_state *pic, pic_checkpoint *here, pic_checkpoint *there)
{
if (here == there)
return;
if (here->depth < there->depth) {
pic_wind(pic, here, there->prev);
pic_apply0(pic, there->in);
}
else {
pic_apply0(pic, there->out);
pic_wind(pic, here->prev, there);
}
}
void
pic_load_point(pic_state *pic, struct pic_cont *cont)
{
pic_jmpbuf *jmp;
for (jmp = pic->jmp; jmp != NULL; jmp = jmp->prev) {
if (jmp == &cont->jmp) {
break;
}
}
if (jmp == NULL) {
pic_errorf(pic, "calling dead escape continuation");
}
pic_wind(pic, pic->cp, cont->cp);
/* load runtime context */
pic->cp = cont->cp;
pic->sp = pic->stbase + cont->sp_offset;
pic->ci = pic->cibase + cont->ci_offset;
pic->xp = pic->xpbase + cont->xp_offset;
pic->arena_idx = cont->arena_idx;
pic->ip = cont->ip;
pic->ptable = cont->ptable;
}
void
pic_load_point(pic_state *pic, struct pic_cont *cont)
{
pic_wind(pic, pic->cp, cont->cp);
/* load runtime context */
pic->cp = cont->cp;
pic->sp = pic->stbase + cont->sp_offset;
pic->ci = pic->cibase + cont->ci_offset;
pic->xp = pic->xpbase + cont->xp_offset;
pic->arena_idx = cont->arena_idx;
pic->ip = cont->ip;
pic->ptable = cont->ptable;
pic->cc = cont->prev;
}
PIC_NORETURN static pic_value
cont_call(pic_state *pic)
{
int argc, i;
pic_value *argv, *retv;
struct fullcont *cont;
pic_get_args(pic, "*", &argc, &argv);
retv = pic_alloca(pic, sizeof(pic_value) * argc);
for (i = 0; i < argc; ++i) {
retv[i] = argv[i];
}
cont = pic_data(pic, pic_closure_ref(pic, 0));
cont->retc = argc;
cont->retv = retv;
/* execute guard handlers */
pic_wind(pic, pic->cp, cont->cp);
restore_cont(pic, cont);
}