int32 memOopClass::compute_derived_offset() {
int32 i = 1;
oop* p = ((oop*) addr()) - i;
while (!is_object_start(*p)) {
i ++, p --;
}
return i;
}
void space::compact(mapOop unmarked_map_map,
space*& copySpace,
oop*& d,
oop*& bd) {
// compact oops and bytes (outwards in), place copies in copySpace
// (and successors, if necessary)
// Leave sentinel at end of oops part
// (utilises extra word between objs and bytes part).
// This causes the is_object_start() loop below to exit.
set_objs_top_sentinel(badOop);
if (copySpace == this) {
d= objs_bottom;
bd= bytes_top;
}
for (oop* p= objs_bottom; p < objs_top; ) {
oopsOop obj = as_oopsOop(p);
if (obj->is_gc_marked()) {
// object survives GC
// figure out size
Map* nm = mapOop(obj->map()->enclosing_mapOop()->gc_unmark())->map_addr();
fint size = nm->object_size(obj);
byteVectorOop bv= NULL;
int32 bsize= 0;
if (nm->is_byteVector()) {
bv= byteVectorOop(obj);
bsize= bv->lengthWords();
}
if (copySpace != this && !copySpace->would_fit(size, bsize)) {
copySpace= ((oldSpace*)copySpace)->next_space;
d= copySpace->objs_bottom;
bd= copySpace->bytes_top;
}
// check for special map processing
if (obj->map() == Memory->map_map) {
// adjust dependencies first
as_mapOop(p)->map_addr()->shift_map(as_mapOop(d)->map_addr());
}
// do compaction
if (bv) {
// compact bytes part up
oop* bp = (oop*) bv->bytes();
assert(copySpace != this || bp + bsize <= bd,
"bytes parts aren't in order");
copy_words_down((int32*)bp + bsize, (int32*)bd, bsize);
bd -= bsize;
bv->set_bytes((char*) bd);
}
// compact oops part down
copy_oops_up(p, d, size);
as_oopsOop(d)->gc_moved();
d += size;
p += size;
if (copySpace != this) {
copySpace->objs_top= d;
copySpace->bytes_bottom= bd;
}
} else {
// object is dying
// check for special map processing
if (((memOopClass*)p)->_map == unmarked_map_map) {
// delete the dying map
as_mapOop(p)->map_addr()->delete_map();
}
// skip to next object
// (can't use object's map to compute object size,
// since it might be destroyed by now)
for (p += 2; // skip mark and map
!is_object_start(*p);
p++) ;
assert(p <= objs_top, "compacter ran off end");
}
}
assert(d < bd, "didn't compact anything");
if (copySpace == this) {
objs_top= d;
bytes_bottom= bd;
}
}
