1 /*
2 * Copyright (c) 1998, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_RUNTIME_HANDLES_INLINE_HPP
26 #define SHARE_RUNTIME_HANDLES_INLINE_HPP
27
28 #include "runtime/handles.hpp"
29
30 #include "runtime/javaThread.hpp"
31 #include "oops/metadata.hpp"
32 #include "oops/oop.hpp"
33
34 // these inline functions are in a separate file to break an include cycle
35 // between Thread and Handle
36
37 inline Handle::Handle(Thread* thread, oop obj) {
38 assert(thread == Thread::current(), "sanity check");
39 if (obj == nullptr) {
40 _handle = nullptr;
41 } else {
42 _handle = thread->handle_area()->allocate_handle(obj);
43 }
44 }
45
46 inline void Handle::replace(oop obj) {
47 // Unlike in OopHandle::replace, we shouldn't use a barrier here.
48 // OopHandle has its storage in OopStorage, which is walked concurrently and uses barriers.
49 // Handle is thread private, and iterated by Thread::oops_do, which is why it shouldn't have any barriers at all.
50 assert(_handle != nullptr, "should not use replace");
51 *_handle = obj;
52 }
53
54 // Inline constructors for Specific Handles for different oop types
55 #define DEF_HANDLE_CONSTR(type, is_a) \
56 inline type##Handle::type##Handle (Thread* thread, type##Oop obj) : Handle(thread, (oop)obj) { \
57 assert(is_null() || ((oop)obj)->is_a(), "illegal type"); \
58 }
59
60 DEF_HANDLE_CONSTR(instance , is_instance_noinline )
61 DEF_HANDLE_CONSTR(array , is_array_noinline )
62 DEF_HANDLE_CONSTR(objArray , is_objArray_noinline )
63 DEF_HANDLE_CONSTR(typeArray, is_typeArray_noinline)
64 DEF_HANDLE_CONSTR(flatArray, is_flatArray_noinline)
65 DEF_HANDLE_CONSTR(refArray , is_refArray_noinline )
66
67 // Constructor for metadata handles
68 #define DEF_METADATA_HANDLE_FN(name, type) \
69 inline name##Handle::name##Handle(Thread* thread, type* obj) : _value(obj), _thread(thread) { \
70 if (obj != nullptr) { \
71 assert(((Metadata*)obj)->is_valid(), "obj is valid"); \
72 assert(_thread == Thread::current(), "thread must be current"); \
73 assert(_thread->is_in_live_stack((address)this), "not on stack?"); \
74 _thread->metadata_handles()->push((Metadata*)obj); \
75 } \
76 } \
77
78 DEF_METADATA_HANDLE_FN(method, Method)
79 DEF_METADATA_HANDLE_FN(constantPool, ConstantPool)
80
81 inline void HandleMark::push() {
82 // This is intentionally a NOP. pop_and_restore will reset
83 // values to the HandleMark further down the stack, typically
84 // in JavaCalls::call_helper.
85 DEBUG_ONLY(_area->_handle_mark_nesting++);
86 }
87
88 inline void HandleMark::pop_and_restore() {
89 // Delete later chunks
90 if(_chunk->next() != nullptr) {
91 assert(_area->size_in_bytes() > size_in_bytes(), "Sanity check");
92 chop_later_chunks();
93 } else {
94 assert(_area->size_in_bytes() == size_in_bytes(), "Sanity check");
95 }
96 // Roll back arena to saved top markers
97 _area->_chunk = _chunk;
98 _area->_hwm = _hwm;
99 _area->_max = _max;
100 DEBUG_ONLY(_area->_handle_mark_nesting--);
101 }
102
103 inline HandleMarkCleaner::HandleMarkCleaner(Thread* thread) {
104 _thread = thread;
105 _thread->last_handle_mark()->push();
106 }
107
108 inline HandleMarkCleaner::~HandleMarkCleaner() {
109 _thread->last_handle_mark()->pop_and_restore();
110 }
111
112 #endif // SHARE_RUNTIME_HANDLES_INLINE_HPP