1 /*
2 * Copyright (c) 2005, 2014, 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_VM_OOPS_KLASS_INLINE_HPP
26 #define SHARE_VM_OOPS_KLASS_INLINE_HPP
27
28 #include "memory/universe.hpp"
29 #include "oops/instanceClassLoaderKlass.inline.hpp"
30 #include "oops/instanceKlass.inline.hpp"
31 #include "oops/instanceMirrorKlass.inline.hpp"
32 #include "oops/instanceRefKlass.inline.hpp"
33 #include "oops/klass.hpp"
34 #include "oops/markOop.hpp"
35 #include "oops/objArrayKlass.inline.hpp"
36 #include "oops/typeArrayKlass.inline.hpp"
37
38 inline void Klass::set_prototype_header(markOop header) {
39 assert(!header->has_bias_pattern() || oop_is_instance(), "biased locking currently only supported for Java instances");
40 _prototype_header = header;
41 }
42
43 inline bool Klass::is_null(Klass* obj) { return obj == NULL; }
44 inline bool Klass::is_null(narrowKlass obj) { return obj == 0; }
45
46 // Encoding and decoding for klass field.
47
48 inline bool check_klass_alignment(Klass* obj) {
49 return (intptr_t)obj % KlassAlignmentInBytes == 0;
50 }
51
52 inline narrowKlass Klass::encode_klass_not_null(Klass* v) {
53 assert(!is_null(v), "klass value can never be zero");
54 assert(check_klass_alignment(v), "Address not aligned");
55 int shift = Universe::narrow_klass_shift();
56 uint64_t pd = (uint64_t)(pointer_delta((void*)v, Universe::narrow_klass_base(), 1));
57 assert(KlassEncodingMetaspaceMax > pd, "change encoding max if new encoding");
58 uint64_t result = pd >> shift;
59 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow klass pointer overflow");
60 assert(decode_klass(result) == v, "reversibility");
61 return (narrowKlass)result;
62 }
63
64 inline narrowKlass Klass::encode_klass(Klass* v) {
65 return is_null(v) ? (narrowKlass)0 : encode_klass_not_null(v);
66 }
67
68 inline Klass* Klass::decode_klass_not_null(narrowKlass v) {
69 assert(!is_null(v), "narrow klass value can never be zero");
70 int shift = Universe::narrow_klass_shift();
71 Klass* result = (Klass*)(void*)((uintptr_t)Universe::narrow_klass_base() + ((uintptr_t)v << shift));
72 assert(check_klass_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
73 return result;
74 }
75
76 inline Klass* Klass::decode_klass(narrowKlass v) {
77 return is_null(v) ? (Klass*)NULL : decode_klass_not_null(v);
78 }
79
80 #define CONCRETE_KLASS_DO_AND_RETURN(the_klass, todo) \
81 do { \
82 switch ((the_klass)->dispatch_tag()) { \
83 case Klass::_instance: return InstanceKlass::cast(the_klass)->todo; \
84 case Klass::_instance_ref: return InstanceRefKlass::cast(the_klass)->todo; \
85 case Klass::_instance_mirror: return InstanceMirrorKlass::cast(the_klass)->todo; \
86 case Klass::_instance_class_loader: return InstanceClassLoaderKlass::cast(the_klass)->todo; \
87 case Klass::_obj_array: return ObjArrayKlass::cast(the_klass)->todo; \
88 case Klass::_type_array: return TypeArrayKlass::cast(the_klass)->todo; \
89 default: fatal("Incorrect dispatch index"); return 0; \
90 } \
91 } while (false)
92
93 #endif // SHARE_VM_OOPS_KLASS_INLINE_HPP