void InterpretedIC::update_inline_cache(InterpretedIC* ic, frame* f, Bytecodes::Code send_code, klassOop klass, LookupResult result) {
// update inline cache
if (ic->is_empty() && ic->send_type() != Bytecodes::megamorphic_send) {
// fill ic for the first time
Bytecodes::Code new_send_code = Bytecodes::halt;
if (result.is_entry()) {
methodOop method = result.method();
if (UseAccessMethods && Bytecodes::has_access_send_code(send_code) && method->is_accessMethod()) {
// access method found ==> switch to access send
new_send_code = Bytecodes::access_send_code_for(send_code);
ic->set(new_send_code, method, klass);
} else if (UsePredictedMethods && Bytecodes::has_predicted_send_code(send_code) && method->is_special_primitiveMethod()) {
// predictable method found ==> switch to predicted send
// NB: ic of predicted send should be empty so that the compiler knows whether another type occurred or not
// i.e., {predicted + empty} --> 1 class, {predicted + nonempty} --> 2 klasses (polymorphic)
// but: this actually doesn't work (yet?) since the interpreter fills the ic on any failure (e.g. overflow)
new_send_code = method->special_primitive_code();
method = methodOop(ic->selector()); // ic must stay empty
klass = NULL; // ic must stay empty
ic->set(new_send_code, method, klass);
} else {
// jump table entry found ==> switch to compiled send
new_send_code = Bytecodes::compiled_send_code_for(send_code);
ic->set(new_send_code, oop(result.entry()->entry_point()), klass);
}
} else {
// methodOop found
methodOop method = result.method();
if (UseAccessMethods && Bytecodes::has_access_send_code(send_code) && method->is_accessMethod()) {
// access method found ==> switch to access send
new_send_code = Bytecodes::access_send_code_for(send_code);
} else if (UsePredictedMethods && Bytecodes::has_predicted_send_code(send_code) && method->is_special_primitiveMethod()) {
// predictable method found ==> switch to predicted send
// NB: ic of predicted send should be empty so that the compiler knows whether another type occurred or not
// i.e., {predicted + empty} --> 1 class, {predicted + nonempty} --> 2 klasses (polymorphic)
// but: this actually doesn't work (yet?) since the interpreter fills the ic on any failure (e.g. overflow)
new_send_code = method->special_primitive_code();
method = methodOop(ic->selector()); // ic must stay empty
klass = NULL; // ic must stay empty
} else if (UsePrimitiveMethods && method->is_primitiveMethod()) {
// primitive method found ==> switch to primitive send
new_send_code = Bytecodes::primitive_send_code_for(send_code);
Unimplemented(); // take this out when all primitive send bytecodes implemented
} else {
// normal interpreted send ==> do not change
new_send_code = send_code;
assert(new_send_code == Bytecodes::original_send_code_for(send_code), "bytecode should not change");
}
assert(new_send_code != Bytecodes::halt, "new_send_code not set");
ic->set(new_send_code, method, klass);
}
} else {
// ic not empty
switch (ic->send_type()) {
// monomorphic send
case Bytecodes::accessor_send : // fall through
case Bytecodes::predicted_send : // fall through
case Bytecodes::compiled_send : // fall through
case Bytecodes::interpreted_send: {
// switch to polymorphic send with 2 entries
objArrayOop pic = Interpreter_PICs::allocate(2);
Interpreter_PICs::set_first(pic, ic->first_word(), ic->second_word());
Interpreter_PICs::set_second(pic, result.value(), klass);
ic->set(Bytecodes::polymorphic_send_code_for(send_code), ic->selector(), pic);
break;
}
// polymorphic send
case Bytecodes::polymorphic_send: {
objArrayOop old_pic = ic->pic_array();
objArrayOop new_pic = Interpreter_PICs::extend(old_pic); // add an entry to the PIC if appropriate
if (new_pic == NULL) {
// switch to megamorphic send
if (Bytecodes::is_super_send(send_code)) {
ic->set(Bytecodes::megamorphic_send_code_for(send_code), result.value(), klass);
} else {
ic->set(Bytecodes::megamorphic_send_code_for(send_code), ic->selector(), NULL);
}
} else {
// still a polymorphic send, add entry and set ic to new_pic
Interpreter_PICs::set_last(new_pic, result.value(), klass);
ic->set(send_code, ic->selector(), new_pic);
}
// recycle old pic
Interpreter_PICs::deallocate(old_pic);
break;
}
// megamorphic send
case Bytecodes::megamorphic_send: {
if (Bytecodes::is_super_send(send_code)) {
ic->set(send_code, result.value(), klass);
}
break;
}
default: ShouldNotReachHere();
}
}
// redo send (reset instruction pointer)
f->set_hp(ic->send_code_addr());
}
void InterpretedIC::cleanup() {
if (is_empty()) return; // Nothing to cleanup
switch (send_type()) {
case Bytecodes::accessor_send: // fall through
case Bytecodes::primitive_send: // fall through
case Bytecodes::predicted_send: // fall through
case Bytecodes::interpreted_send:
{ // check if the interpreted send should be replaced by a compiled send
klassOop receiver_klass = klassOop(second_word());
assert(receiver_klass->is_klass(), "receiver klass must be a klass");
methodOop method = methodOop(first_word());
assert(method->is_method(), "first word in interpreter IC must be method");
if (!Bytecodes::is_super_send(send_code())) {
// super sends cannot be handled since the sending method holder is unknown at this point.
LookupKey key(receiver_klass, selector());
LookupResult result = lookupCache::lookup(&key);
if (!result.matches(method)) {
replace(result, receiver_klass);
}
}
}
break;
case Bytecodes::compiled_send:
{ // check if the current compiled send is valid
klassOop receiver_klass = klassOop(second_word());
assert(receiver_klass->is_klass(), "receiver klass must be a klass");
jumpTableEntry* entry = (jumpTableEntry*) first_word();
nmethod* nm = entry->method();
LookupResult result = lookupCache::lookup(&nm->key);
if (!result.matches(nm)) {
replace(result, receiver_klass);
}
}
break;
case Bytecodes::megamorphic_send:
// Note that with the current definition of is_empty()
// this will not be called for normal megamorphic sends
// since they store only the selector.
{ klassOop receiver_klass = klassOop(second_word());
if (first_word()->is_smi()) {
jumpTableEntry* entry = (jumpTableEntry*) first_word();
nmethod* nm = entry->method();
LookupResult result = lookupCache::lookup(&nm->key);
if (!result.matches(nm)) {
replace(result, receiver_klass);
}
} else {
methodOop method = methodOop(first_word());
assert(method->is_method(), "first word in interpreter IC must be method");
if (!Bytecodes::is_super_send(send_code())) {
// super sends cannot be handled since the sending method holder is unknown at this point.
LookupKey key(receiver_klass, selector());
LookupResult result = lookupCache::lookup(&key);
if (!result.matches(method)) {
replace(result, receiver_klass);
}
}
}
}
break;
case Bytecodes::polymorphic_send:
{
// %implementation note:
// when cleaning up we can always preserve the old pic since the
// the only transitions are:
// (compiled -> compiled)
// (compiled -> interpreted)
// (interpreted -> compiled)
// in case of a super send we do not have to cleanup because
// no nmethods are compiled for super sends.
if (!Bytecodes::is_super_send(send_code())) {
objArrayOop pic = pic_array();
for (int index = pic->length(); index > 0; index -= 2) {
klassOop klass = klassOop(pic->obj_at(index));
assert(klass->is_klass(), "receiver klass must be klass");
oop first = pic->obj_at(index-1);
if (first->is_smi()) {
jumpTableEntry* entry = (jumpTableEntry*) first;
nmethod* nm = entry->method();
LookupResult result = lookupCache::lookup(&nm->key);
if (!result.matches(nm)) {
pic->obj_at_put(index-1, result.value());
}
} else {
methodOop method = methodOop(first);
assert(method->is_method(), "first word in interpreter IC must be method");
LookupKey key(klass, selector());
LookupResult result = lookupCache::lookup(&key);
if (!result.matches(method)) {
pic->obj_at_put(index-1, result.value());
}
}
}
}
}
}
}
