1 /*
 2  * Copyright Amazon.com Inc. 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.
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23  */
24 
25 #ifndef SHARE_OOPS_MARKWORD_INLINE_HPP
26 #define SHARE_OOPS_MARKWORD_INLINE_HPP
27 
28 #include "oops/markWord.hpp"
29 #include "oops/compressedOops.inline.hpp"
30 
31 narrowKlass markWord::narrow_klass() const {
32 #ifdef _LP64
33   assert(UseCompactObjectHeaders, "only used with compact object headers");
34   return narrowKlass(value() >> klass_shift);
35 #else
36   ShouldNotReachHere();
37   return 0;
38 #endif
39 }
40 
41 markWord markWord::set_narrow_klass(narrowKlass nklass) const {
42 #ifdef _LP64
43   assert(UseCompactObjectHeaders, "only used with compact object headers");
44   return markWord((value() & ~klass_mask_in_place) | ((uintptr_t) nklass << klass_shift));
45 #else
46   ShouldNotReachHere();
47   return markWord(0);
48 #endif
49 }
50 
51 Klass* markWord::klass() const {
52 #ifdef _LP64
53   assert(UseCompactObjectHeaders, "only used with compact object headers");
54   return CompressedKlassPointers::decode_not_null(narrow_klass());
55 #else
56   ShouldNotReachHere();
57   return nullptr;
58 #endif
59 }
60 
61 Klass* markWord::klass_or_null() const {
62 #ifdef _LP64
63   assert(UseCompactObjectHeaders, "only used with compact object headers");
64   return CompressedKlassPointers::decode(narrow_klass());
65 #else
66   ShouldNotReachHere();
67   return nullptr;
68 #endif
69 }
70 
71 Klass* markWord::klass_without_asserts() const {
72 #ifdef _LP64
73   assert(UseCompactObjectHeaders, "only used with compact object headers");
74   return CompressedKlassPointers::decode_without_asserts(narrow_klass());
75 #else
76   ShouldNotReachHere();
77   return nullptr;
78 #endif
79 }
80 
81 markWord markWord::set_klass(Klass* klass) const {
82 #ifdef _LP64
83   assert(UseCompactObjectHeaders, "only used with compact object headers");
84   assert(UseCompressedClassPointers, "expect compressed klass pointers");
85   narrowKlass nklass = CompressedKlassPointers::encode(const_cast<Klass*>(klass));
86   return set_narrow_klass(nklass);
87 #else
88   ShouldNotReachHere();
89   return markWord();
90 #endif
91 }
92 
93 #endif // SHARE_OOPS_MARKWORD_INLINE_HPP