< prev index next > src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp
Print this page
/*
! * Copyright (c) 2003, 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
/*
! * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
__ lea(lock_reg, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
// Load the oop from the handle
__ movptr(obj_reg, Address(oop_handle_reg, 0));
! if (UseBiasedLocking) {
! __ biased_locking_enter(lock_reg, obj_reg, swap_reg, rscratch1, rscratch2, false, lock_done, &slow_path_lock);
! }
! // Load immediate 1 into swap_reg %rax
! __ movl(swap_reg, 1);
! // Load (object->mark() | 1) into swap_reg %rax
! __ orptr(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
! // Save (object->mark() | 1) into BasicLock's displaced header
! __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
! // src -> dest iff dest == rax else rax <- dest
! __ lock();
! __ cmpxchgptr(lock_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
! __ jcc(Assembler::equal, lock_done);
! // 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) rsp <= mark < mark + os::pagesize()
! // These 3 tests can be done by evaluating the following
! // expression: ((mark - rsp) & (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 %rax as the result of cmpxchg
! __ subptr(swap_reg, rsp);
! __ andptr(swap_reg, 3 - os::vm_page_size());
! // Save the test result, for recursive case, the result is zero
! __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
! __ jcc(Assembler::notEqual, slow_path_lock);
// Slow path will re-enter here
__ bind(lock_done);
}
__ lea(lock_reg, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
// Load the oop from the handle
__ movptr(obj_reg, Address(oop_handle_reg, 0));
! if (LockingMode == LM_MONITOR) {
! __ jmp(slow_path_lock);
! } else if (LockingMode == LM_LEGACY) {
+ if (UseBiasedLocking) {
+ __ biased_locking_enter(lock_reg, obj_reg, swap_reg, rscratch1, rscratch2, false, lock_done, &slow_path_lock);
+ }
! // Load immediate 1 into swap_reg %rax
! __ movl(swap_reg, 1);
! // Load (object->mark() | 1) into swap_reg %rax
! __ orptr(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
! // Save (object->mark() | 1) into BasicLock's displaced header
! __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
! // src -> dest iff dest == rax else rax <- dest
! __ lock();
! __ cmpxchgptr(lock_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
! __ jcc(Assembler::equal, lock_done);
! // 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) rsp <= mark < mark + os::pagesize()
! // These 3 tests can be done by evaluating the following
! // expression: ((mark - rsp) & (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 %rax as the result of cmpxchg
! __ subptr(swap_reg, rsp);
! __ andptr(swap_reg, 3 - os::vm_page_size());
! // Save the test result, for recursive case, the result is zero
! __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
! __ jcc(Assembler::notEqual, slow_path_lock);
+ } else {
+ assert(LockingMode == LM_LIGHTWEIGHT, "must be");
+ __ lightweight_lock(obj_reg, swap_reg, r15_thread, rscratch1, slow_path_lock);
+ }
// Slow path will re-enter here
__ bind(lock_done);
}
if (UseBiasedLocking) {
__ biased_locking_exit(obj_reg, old_hdr, done);
}
! // Simple recursive lock?
! __ cmpptr(Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size), (int32_t)NULL_WORD);
! __ jcc(Assembler::equal, done);
// Must save rax if if it is live now because cmpxchg must use it
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
save_native_result(masm, ret_type, stack_slots);
}
!
! // get address of the stack lock
! __ lea(rax, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
! // get old displaced header
! __ movptr(old_hdr, Address(rax, 0));
!
! // Atomic swap old header if oop still contains the stack lock
! __ lock();
! __ cmpxchgptr(old_hdr, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
! __ jcc(Assembler::notEqual, slow_path_unlock);
// slow path re-enters here
__ bind(unlock_done);
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
restore_native_result(masm, ret_type, stack_slots);
if (UseBiasedLocking) {
__ biased_locking_exit(obj_reg, old_hdr, done);
}
! if (LockingMode == LM_LEGACY) {
+ // Simple recursive lock?
! __ cmpptr(Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size), (int32_t)NULL_WORD);
! __ jcc(Assembler::equal, done);
+ }
// Must save rax if if it is live now because cmpxchg must use it
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
save_native_result(masm, ret_type, stack_slots);
}
! if (LockingMode == LM_MONITOR) {
! __ jmp(slow_path_unlock);
! } else if (LockingMode == LM_LEGACY) {
! // get address of the stack lock
! __ lea(rax, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
! // get old displaced header
! __ movptr(old_hdr, Address(rax, 0));
!
! // Atomic swap old header if oop still contains the stack lock
! __ lock();
+ __ cmpxchgptr(old_hdr, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
+ __ jcc(Assembler::notEqual, slow_path_unlock);
+ } else {
+ assert(LockingMode == LM_LIGHTWEIGHT, "must be");
+ __ lightweight_unlock(obj_reg, swap_reg, r15_thread, lock_reg, slow_path_unlock);
+ }
// slow path re-enters here
__ bind(unlock_done);
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
restore_native_result(masm, ret_type, stack_slots);
< prev index next >