1664 __ mv(oop_handle_reg, c_rarg1);
1665
1666 // Get address of the box
1667
1668 __ la(lock_reg, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1669
1670 // Load the oop from the handle
1671 __ ld(obj_reg, Address(oop_handle_reg, 0));
1672
1673 if (LockingMode == LM_MONITOR) {
1674 __ j(slow_path_lock);
1675 } else if (LockingMode == LM_LEGACY) {
1676 // Load (object->mark() | 1) into swap_reg % x10
1677 __ ld(t0, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
1678 __ ori(swap_reg, t0, 1);
1679
1680 // Save (object->mark() | 1) into BasicLock's displaced header
1681 __ sd(swap_reg, Address(lock_reg, mark_word_offset));
1682
1683 // src -> dest if dest == x10 else x10 <- dest
1684 __ cmpxchg_obj_header(x10, lock_reg, obj_reg, t0, count, /*fallthrough*/nullptr);
1685
1686 // Test if the oopMark is an obvious stack pointer, i.e.,
1687 // 1) (mark & 3) == 0, and
1688 // 2) sp <= mark < mark + os::pagesize()
1689 // These 3 tests can be done by evaluating the following
1690 // expression: ((mark - sp) & (3 - os::vm_page_size())),
1691 // assuming both stack pointer and pagesize have their
1692 // least significant 2 bits clear.
1693 // NOTE: the oopMark is in swap_reg % 10 as the result of cmpxchg
1694
1695 __ sub(swap_reg, swap_reg, sp);
1696 __ andi(swap_reg, swap_reg, 3 - (int)os::vm_page_size());
1697
1698 // Save the test result, for recursive case, the result is zero
1699 __ sd(swap_reg, Address(lock_reg, mark_word_offset));
1700 __ bnez(swap_reg, slow_path_lock);
1701 } else {
1702 assert(LockingMode == LM_LIGHTWEIGHT, "");
1703 __ ld(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
1704 __ fast_lock(obj_reg, swap_reg, tmp, t0, slow_path_lock);
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1664 __ mv(oop_handle_reg, c_rarg1);
1665
1666 // Get address of the box
1667
1668 __ la(lock_reg, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1669
1670 // Load the oop from the handle
1671 __ ld(obj_reg, Address(oop_handle_reg, 0));
1672
1673 if (LockingMode == LM_MONITOR) {
1674 __ j(slow_path_lock);
1675 } else if (LockingMode == LM_LEGACY) {
1676 // Load (object->mark() | 1) into swap_reg % x10
1677 __ ld(t0, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
1678 __ ori(swap_reg, t0, 1);
1679
1680 // Save (object->mark() | 1) into BasicLock's displaced header
1681 __ sd(swap_reg, Address(lock_reg, mark_word_offset));
1682
1683 // src -> dest if dest == x10 else x10 <- dest
1684 __ cmpxchg_obj_header(x10, lock_reg, obj_reg, t0, count, /*fallthrough*/NULL);
1685
1686 // Test if the oopMark is an obvious stack pointer, i.e.,
1687 // 1) (mark & 3) == 0, and
1688 // 2) sp <= mark < mark + os::pagesize()
1689 // These 3 tests can be done by evaluating the following
1690 // expression: ((mark - sp) & (3 - os::vm_page_size())),
1691 // assuming both stack pointer and pagesize have their
1692 // least significant 2 bits clear.
1693 // NOTE: the oopMark is in swap_reg % 10 as the result of cmpxchg
1694
1695 __ sub(swap_reg, swap_reg, sp);
1696 __ andi(swap_reg, swap_reg, 3 - (int)os::vm_page_size());
1697
1698 // Save the test result, for recursive case, the result is zero
1699 __ sd(swap_reg, Address(lock_reg, mark_word_offset));
1700 __ bnez(swap_reg, slow_path_lock);
1701 } else {
1702 assert(LockingMode == LM_LIGHTWEIGHT, "");
1703 __ ld(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
1704 __ fast_lock(obj_reg, swap_reg, tmp, t0, slow_path_lock);
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