79 
 80 void C2FastUnlockLightweightStub::emit(C2_MacroAssembler& masm) {
 81   assert(_t == rax, "must be");
 82 
 83   Label restore_held_monitor_count_and_slow_path;
 84 
 85   { // Restore lock-stack and handle the unlock in runtime.
 86 
 87     __ bind(_push_and_slow_path);
 88 #ifdef ASSERT
 89     // The obj was only cleared in debug.
 90     __ movl(_t, Address(_thread, JavaThread::lock_stack_top_offset()));
 91     __ movptr(Address(_thread, _t), _obj);
 92 #endif
 93     __ addl(Address(_thread, JavaThread::lock_stack_top_offset()), oopSize);
 94   }
 95 
 96   { // Restore held monitor count and slow path.
 97 
 98     __ bind(restore_held_monitor_count_and_slow_path);

 99     // Restore held monitor count.
100     __ increment(Address(_thread, JavaThread::held_monitor_count_offset()));
101     // increment will always result in ZF = 0 (no overflows).
102     __ jmp(slow_path_continuation());
103   }
104 
105   { // Handle monitor medium path.
106 
107     __ bind(_check_successor);
108 
109     Label fix_zf_and_unlocked;
110     const Register monitor = _mark;
111 
112 #ifndef _LP64
113     __ jmpb(restore_held_monitor_count_and_slow_path);
114 #else // _LP64
115     // successor null check.
116     __ cmpptr(Address(monitor, OM_OFFSET_NO_MONITOR_VALUE_TAG(succ)), NULL_WORD);
117     __ jccb(Assembler::equal, restore_held_monitor_count_and_slow_path);
118 

 79 
 80 void C2FastUnlockLightweightStub::emit(C2_MacroAssembler& masm) {
 81   assert(_t == rax, "must be");
 82 
 83   Label restore_held_monitor_count_and_slow_path;
 84 
 85   { // Restore lock-stack and handle the unlock in runtime.
 86 
 87     __ bind(_push_and_slow_path);
 88 #ifdef ASSERT
 89     // The obj was only cleared in debug.
 90     __ movl(_t, Address(_thread, JavaThread::lock_stack_top_offset()));
 91     __ movptr(Address(_thread, _t), _obj);
 92 #endif
 93     __ addl(Address(_thread, JavaThread::lock_stack_top_offset()), oopSize);
 94   }
 95 
 96   { // Restore held monitor count and slow path.
 97 
 98     __ bind(restore_held_monitor_count_and_slow_path);
 99     __ bind(_slow_path);
100     // Restore held monitor count.
101     __ increment(Address(_thread, JavaThread::held_monitor_count_offset()));
102     // increment will always result in ZF = 0 (no overflows).
103     __ jmp(slow_path_continuation());
104   }
105 
106   { // Handle monitor medium path.
107 
108     __ bind(_check_successor);
109 
110     Label fix_zf_and_unlocked;
111     const Register monitor = _mark;
112 
113 #ifndef _LP64
114     __ jmpb(restore_held_monitor_count_and_slow_path);
115 #else // _LP64
116     // successor null check.
117     __ cmpptr(Address(monitor, OM_OFFSET_NO_MONITOR_VALUE_TAG(succ)), NULL_WORD);
118     __ jccb(Assembler::equal, restore_held_monitor_count_and_slow_path);
119