void vframeArrayElement::unpack_on_stack(int caller_actual_parameters,
int callee_parameters,
int callee_locals,
frame* caller,
bool is_top_frame,
bool is_bottom_frame,
int exec_mode) {
JavaThread* thread = (JavaThread*) Thread::current();
// Look at bci and decide on bcp and continuation pc
address bcp;
// C++ interpreter doesn't need a pc since it will figure out what to do when it
// begins execution
address pc;
bool use_next_mdp = false; // true if we should use the mdp associated with the next bci
// rather than the one associated with bcp
if (raw_bci() == SynchronizationEntryBCI) {
// We are deoptimizing while hanging in prologue code for synchronized method
bcp = method()->bcp_from(0); // first byte code
pc = Interpreter::deopt_entry(vtos, 0); // step = 0 since we don't skip current bytecode
} else if (should_reexecute()) { //reexecute this bytecode
assert(is_top_frame, "reexecute allowed only for the top frame");
bcp = method()->bcp_from(bci());
pc = Interpreter::deopt_reexecute_entry(method(), bcp);
} else {
bcp = method()->bcp_from(bci());
pc = Interpreter::deopt_continue_after_entry(method(), bcp, callee_parameters, is_top_frame);
use_next_mdp = true;
}
assert(Bytecodes::is_defined(*bcp), "must be a valid bytecode");
// Monitorenter and pending exceptions:
//
// For Compiler2, there should be no pending exception when deoptimizing at monitorenter
// because there is no safepoint at the null pointer check (it is either handled explicitly
// or prior to the monitorenter) and asynchronous exceptions are not made "pending" by the
// runtime interface for the slow case (see JRT_ENTRY_FOR_MONITORENTER). If an asynchronous
// exception was processed, the bytecode pointer would have to be extended one bytecode beyond
// the monitorenter to place it in the proper exception range.
//
// For Compiler1, deoptimization can occur while throwing a NullPointerException at monitorenter,
// in which case bcp should point to the monitorenter since it is within the exception's range.
assert(*bcp != Bytecodes::_monitorenter || is_top_frame, "a _monitorenter must be a top frame");
assert(thread->deopt_nmethod() != NULL, "nmethod should be known");
guarantee(!(thread->deopt_nmethod()->is_compiled_by_c2() &&
*bcp == Bytecodes::_monitorenter &&
exec_mode == Deoptimization::Unpack_exception),
"shouldn't get exception during monitorenter");
int popframe_preserved_args_size_in_bytes = 0;
int popframe_preserved_args_size_in_words = 0;
if (is_top_frame) {
JvmtiThreadState *state = thread->jvmti_thread_state();
if (JvmtiExport::can_pop_frame() &&
(thread->has_pending_popframe() || thread->popframe_forcing_deopt_reexecution())) {
if (thread->has_pending_popframe()) {
// Pop top frame after deoptimization
#ifndef CC_INTERP
pc = Interpreter::remove_activation_preserving_args_entry();
#else
// Do an uncommon trap type entry. c++ interpreter will know
// to pop frame and preserve the args
pc = Interpreter::deopt_entry(vtos, 0);
use_next_mdp = false;
#endif
} else {
// Reexecute invoke in top frame
pc = Interpreter::deopt_entry(vtos, 0);
use_next_mdp = false;
popframe_preserved_args_size_in_bytes = in_bytes(thread->popframe_preserved_args_size());
// Note: the PopFrame-related extension of the expression stack size is done in
// Deoptimization::fetch_unroll_info_helper
popframe_preserved_args_size_in_words = in_words(thread->popframe_preserved_args_size_in_words());
}
} else if (JvmtiExport::can_force_early_return() && state != NULL && state->is_earlyret_pending()) {
// Force early return from top frame after deoptimization
#ifndef CC_INTERP
pc = Interpreter::remove_activation_early_entry(state->earlyret_tos());
#else
// TBD: Need to implement ForceEarlyReturn for CC_INTERP (ia64)
#endif
} else {
// Possibly override the previous pc computation of the top (youngest) frame
switch (exec_mode) {
case Deoptimization::Unpack_deopt:
// use what we've got
break;
case Deoptimization::Unpack_exception:
// exception is pending
pc = SharedRuntime::raw_exception_handler_for_return_address(thread, pc);
// [phh] We're going to end up in some handler or other, so it doesn't
// matter what mdp we point to. See exception_handler_for_exception()
// in interpreterRuntime.cpp.
break;
case Deoptimization::Unpack_uncommon_trap:
case Deoptimization::Unpack_reexecute:
// redo last byte code
pc = Interpreter::deopt_entry(vtos, 0);
use_next_mdp = false;
break;
default:
ShouldNotReachHere();
}
}
}
// Setup the interpreter frame
assert(method() != NULL, "method must exist");
int temps = expressions()->size();
int locks = monitors() == NULL ? 0 : monitors()->number_of_monitors();
Interpreter::layout_activation(method(),
temps + callee_parameters,
popframe_preserved_args_size_in_words,
locks,
caller_actual_parameters,
callee_parameters,
callee_locals,
caller,
iframe(),
is_top_frame,
is_bottom_frame);
// Update the pc in the frame object and overwrite the temporary pc
// we placed in the skeletal frame now that we finally know the
// exact interpreter address we should use.
_frame.patch_pc(thread, pc);
assert (!method()->is_synchronized() || locks > 0, "synchronized methods must have monitors");
BasicObjectLock* top = iframe()->interpreter_frame_monitor_begin();
for (int index = 0; index < locks; index++) {
top = iframe()->previous_monitor_in_interpreter_frame(top);
BasicObjectLock* src = _monitors->at(index);
top->set_obj(src->obj());
src->lock()->move_to(src->obj(), top->lock());
}
if (ProfileInterpreter) {
iframe()->interpreter_frame_set_mdx(0); // clear out the mdp.
}
iframe()->interpreter_frame_set_bcx((intptr_t)bcp); // cannot use bcp because frame is not initialized yet
if (ProfileInterpreter) {
methodDataOop mdo = method()->method_data();
if (mdo != NULL) {
int bci = iframe()->interpreter_frame_bci();
if (use_next_mdp) ++bci;
address mdp = mdo->bci_to_dp(bci);
iframe()->interpreter_frame_set_mdp(mdp);
}
}
// Unpack expression stack
// If this is an intermediate frame (i.e. not top frame) then this
// only unpacks the part of the expression stack not used by callee
// as parameters. The callee parameters are unpacked as part of the
// callee locals.
int i;
for(i = 0; i < expressions()->size(); i++) {
StackValue *value = expressions()->at(i);
intptr_t* addr = iframe()->interpreter_frame_expression_stack_at(i);
switch(value->type()) {
case T_INT:
*addr = value->get_int();
break;
case T_OBJECT:
*addr = value->get_int(T_OBJECT);
break;
case T_CONFLICT:
// A dead stack slot. Initialize to null in case it is an oop.
*addr = NULL_WORD;
break;
default:
ShouldNotReachHere();
}
}
// Unpack the locals
for(i = 0; i < locals()->size(); i++) {
StackValue *value = locals()->at(i);
intptr_t* addr = iframe()->interpreter_frame_local_at(i);
switch(value->type()) {
case T_INT:
*addr = value->get_int();
break;
case T_OBJECT:
*addr = value->get_int(T_OBJECT);
break;
case T_CONFLICT:
// A dead location. If it is an oop then we need a NULL to prevent GC from following it
*addr = NULL_WORD;
break;
default:
ShouldNotReachHere();
}
}
if (is_top_frame && JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
// An interpreted frame was popped but it returns to a deoptimized
// frame. The incoming arguments to the interpreted activation
// were preserved in thread-local storage by the
// remove_activation_preserving_args_entry in the interpreter; now
// we put them back into the just-unpacked interpreter frame.
// Note that this assumes that the locals arena grows toward lower
// addresses.
if (popframe_preserved_args_size_in_words != 0) {
void* saved_args = thread->popframe_preserved_args();
assert(saved_args != NULL, "must have been saved by interpreter");
#ifdef ASSERT
assert(popframe_preserved_args_size_in_words <=
iframe()->interpreter_frame_expression_stack_size()*Interpreter::stackElementWords,
"expression stack size should have been extended");
#endif // ASSERT
int top_element = iframe()->interpreter_frame_expression_stack_size()-1;
intptr_t* base;
if (frame::interpreter_frame_expression_stack_direction() < 0) {
base = iframe()->interpreter_frame_expression_stack_at(top_element);
} else {
base = iframe()->interpreter_frame_expression_stack();
}
Copy::conjoint_jbytes(saved_args,
base,
popframe_preserved_args_size_in_bytes);
thread->popframe_free_preserved_args();
}
}
#ifndef PRODUCT
if (TraceDeoptimization && Verbose) {
ttyLocker ttyl;
tty->print_cr("[%d Interpreted Frame]", ++unpack_counter);
iframe()->print_on(tty);
RegisterMap map(thread);
vframe* f = vframe::new_vframe(iframe(), &map, thread);
f->print();
tty->print_cr("locals size %d", locals()->size());
tty->print_cr("expression size %d", expressions()->size());
method()->print_value();
tty->cr();
// method()->print_codes();
} else if (TraceDeoptimization) {
tty->print(" ");
method()->print_value();
Bytecodes::Code code = Bytecodes::java_code_at(method(), bcp);
int bci = method()->bci_from(bcp);
tty->print(" - %s", Bytecodes::name(code));
tty->print(" @ bci %d ", bci);
tty->print_cr("sp = " PTR_FORMAT, iframe()->sp());
}
#endif // PRODUCT
// The expression stack and locals are in the resource area don't leave
// a dangling pointer in the vframeArray we leave around for debug
// purposes
_locals = _expressions = NULL;
}
