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// Load the oop from the handle
__ ldr(obj_reg, Address(oop_handle_reg, 0));
if (!UseHeavyMonitors) {
- // Load (object->mark() | 1) into swap_reg %r0
- __ ldr(rscratch1, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
- __ orr(swap_reg, rscratch1, 1);
-
- // Save (object->mark() | 1) into BasicLock's displaced header
- __ str(swap_reg, Address(lock_reg, mark_word_offset));
-
- // src -> dest iff dest == r0 else r0 <- dest
- __ cmpxchg_obj_header(r0, lock_reg, obj_reg, rscratch1, count, /*fallthrough*/NULL);
-
- // Hmm should this move to the slow path code area???
-
- // Test if the oopMark is an obvious stack pointer, i.e.,
- // 1) (mark & 3) == 0, and
- // 2) sp <= mark < mark + os::pagesize()
- // These 3 tests can be done by evaluating the following
- // expression: ((mark - sp) & (3 - os::vm_page_size())),
- // assuming both stack pointer and pagesize have their
- // least significant 2 bits clear.
- // NOTE: the oopMark is in swap_reg %r0 as the result of cmpxchg
-
- __ sub(swap_reg, sp, swap_reg);
- __ neg(swap_reg, swap_reg);
- __ ands(swap_reg, swap_reg, 3 - (int)os::vm_page_size());
-
- // Save the test result, for recursive case, the result is zero
- __ str(swap_reg, Address(lock_reg, mark_word_offset));
- __ br(Assembler::NE, slow_path_lock);
+ if (UseFastLocking) {
+ __ ldr(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
+ __ fast_lock(obj_reg, swap_reg, tmp, rscratch1, slow_path_lock);
+ } else {
+ // Load (object->mark() | 1) into swap_reg %r0
+ __ ldr(rscratch1, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
+ __ orr(swap_reg, rscratch1, 1);
+
+ // Save (object->mark() | 1) into BasicLock's displaced header
+ __ str(swap_reg, Address(lock_reg, mark_word_offset));
+
+ // src -> dest iff dest == r0 else r0 <- dest
+ __ cmpxchg_obj_header(r0, lock_reg, obj_reg, rscratch1, count, /*fallthrough*/NULL);
+
+ // Hmm should this move to the slow path code area???
+
+ // Test if the oopMark is an obvious stack pointer, i.e.,
+ // 1) (mark & 3) == 0, and
+ // 2) sp <= mark < mark + os::pagesize()
+ // These 3 tests can be done by evaluating the following
+ // expression: ((mark - sp) & (3 - os::vm_page_size())),
+ // assuming both stack pointer and pagesize have their
+ // least significant 2 bits clear.
+ // NOTE: the oopMark is in swap_reg %r0 as the result of cmpxchg
+
+ __ sub(swap_reg, sp, swap_reg);
+ __ neg(swap_reg, swap_reg);
+ __ ands(swap_reg, swap_reg, 3 - (int)os::vm_page_size());
+
+ // Save the test result, for recursive case, the result is zero
+ __ str(swap_reg, Address(lock_reg, mark_word_offset));
+ __ br(Assembler::NE, slow_path_lock);
+ }
} else {
__ b(slow_path_lock);
}
__ bind(count);
__ increment(Address(rthread, JavaThread::held_monitor_count_offset()));
// Get locked oop from the handle we passed to jni
__ ldr(obj_reg, Address(oop_handle_reg, 0));
Label done, not_recursive;
- if (!UseHeavyMonitors) {
+ if (!UseHeavyMonitors && !UseFastLocking) {
// Simple recursive lock?
__ ldr(rscratch1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
__ cbnz(rscratch1, not_recursive);
__ decrement(Address(rthread, JavaThread::held_monitor_count_offset()));
__ b(done);
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
save_native_result(masm, ret_type, stack_slots);
}
if (!UseHeavyMonitors) {
- // get address of the stack lock
- __ lea(r0, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
- // get old displaced header
- __ ldr(old_hdr, Address(r0, 0));
-
- // Atomic swap old header if oop still contains the stack lock
- Label count;
- __ cmpxchg_obj_header(r0, old_hdr, obj_reg, rscratch1, count, &slow_path_unlock);
- __ bind(count);
+ if (UseFastLocking) {
+ __ ldr(old_hdr, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
+ __ fast_unlock(obj_reg, old_hdr, swap_reg, rscratch1, slow_path_unlock);
+ } else {
+ // get address of the stack lock
+ __ lea(r0, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
+ // get old displaced header
+ __ ldr(old_hdr, Address(r0, 0));
+
+ // Atomic swap old header if oop still contains the stack lock
+ Label count;
+ __ cmpxchg_obj_header(r0, old_hdr, obj_reg, rscratch1, count, &slow_path_unlock);
+ __ bind(count);
+ }
__ decrement(Address(rthread, JavaThread::held_monitor_count_offset()));
} else {
__ b(slow_path_unlock);
}
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