1 /*
2 * Copyright (c) 2000, 2015, 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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_VM_GC_SHARED_BARRIERSET_HPP
26 #define SHARE_VM_GC_SHARED_BARRIERSET_HPP
27
28 #include "gc/shared/barrierSetConfig.hpp"
29 #include "runtime/access.hpp"
30 #include "runtime/accessBackend.hpp"
31 #include "utilities/fakeRttiSupport.hpp"
32
33 class JavaThread;
34 class BarrierSetCodeGen;
35 class C1BarrierSetCodeGen;
36 class C2BarrierSetCodeGen;
37
38 // This class provides the interface between a barrier implementation and
39 // the rest of the system.
40
41 class BarrierSet: public CHeapObj<mtGC> {
42 friend class VMStructs;
43 public:
44 enum Name {
45 #define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
46 FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
47 #undef BARRIER_SET_DECLARE_BS_ENUM
48 UnknownBS
49 };
50 protected:
51 // Fake RTTI support. For a derived class T to participate
52 // - T must have a corresponding Name entry.
53 // - GetName<T> must be specialized to return the corresponding Name
54 // entry.
55 // - If T is a base class, the constructor must have a FakeRtti
56 // parameter and pass it up to its base class, with the tag set
57 // augmented with the corresponding Name entry.
58 // - If T is a concrete class, the constructor must create a
59 // FakeRtti object whose tag set includes the corresponding Name
60 // entry, and pass it up to its base class.
61 typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
62
63 private:
64 FakeRtti _fake_rtti;
65
66 // Downcast argument to a derived barrier set type.
67 // The cast is checked in a debug build.
68 // T must have a specialization for BarrierSet::GetName<T>.
69 template<typename T> friend T* barrier_set_cast(BarrierSet* bs);
70
71 public:
72 // Note: This is not presently the Name corresponding to the
73 // concrete class of this object.
74 BarrierSet::Name kind() const { return _fake_rtti.concrete_tag(); }
75
76 // Test whether this object is of the type corresponding to bsn.
77 bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
78
79 // End of fake RTTI support.
80
81 protected:
82 BarrierSet(const FakeRtti& fake_rtti) : _fake_rtti(fake_rtti), _code_gen(NULL), _c1_code_gen(NULL), _c2_code_gen(NULL) { }
83 ~BarrierSet() { }
84
85 static BarrierSet* _bs;
86
87 BarrierSetCodeGen* _code_gen;
88 C1BarrierSetCodeGen* _c1_code_gen;
89 C2BarrierSetCodeGen* _c2_code_gen;
90
91 virtual BarrierSetCodeGen* make_code_gen() = 0;
92 virtual C1BarrierSetCodeGen* make_c1_code_gen() = 0;
93 virtual C2BarrierSetCodeGen* make_c2_code_gen() = 0;
94
95 public:
96 static BarrierSet* barrier_set() { return _bs; }
97
98 // Print a description of the memory for the barrier set
99 virtual void print_on(outputStream* st) const = 0;
100
101 virtual void initialize();
102
103 BarrierSetCodeGen* code_gen() {
104 assert(_code_gen != NULL, "should be set");
105 return _code_gen;
106 }
107
108 C1BarrierSetCodeGen* c1_code_gen() {
109 assert(_c1_code_gen != NULL, "should be set");
110 return _c1_code_gen;
111 }
112
113 C2BarrierSetCodeGen* c2_code_gen() {
114 assert(_c2_code_gen != NULL, "should be set");
115 return _c2_code_gen;
116 }
117
118 // The AccessBarrier of a BarrierSet subclass is called by the Access API
119 // to perform decorated accesses.
120 template <DecoratorSet decorators>
121 class AccessBarrier: public BasicAccessBarrier<decorators> {
122 typedef BasicAccessBarrier<decorators> Basic;
123 public:
124 static void oop_store(void* addr, oop value);
125 static void oop_store_at(oop base, ptrdiff_t offset, oop value);
126 static void oop_store_at(nmethod* base, ptrdiff_t offset, oop value);
127 static void oop_store_at(Klass* base, ptrdiff_t offset, oop value);
128
129 static oop oop_load(void* addr);
130 static oop oop_load_at(oop base, ptrdiff_t offset);
131
132 static oop oop_cas(oop new_value, void* addr, oop compare_value);
133 static oop oop_cas_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value);
134
135 static oop oop_swap(oop new_value, void* addr);
136 static oop oop_swap_at(oop new_value, oop base, ptrdiff_t offset);
137 };
138
139 // Support for optimizing compilers to call the barrier set on slow path allocations
140 // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks
141 virtual void on_slowpath_allocation(JavaThread* thread, oop new_obj) {}
142 virtual void on_add_thread(JavaThread* thread) {}
143 virtual void on_destroy_thread(JavaThread* thread) {}
144 virtual void make_parsable(JavaThread* thread) {}
145
146 // Resolve runtime paths for GC barriers accessible through the Access interface
147 // in runtime/access.hpp
148 template <DecoratorSet decorators, typename T, BarrierType barrier_type>
149 void* resolve_barrier();
150
151 template <DecoratorSet decorators>
152 void* resolve_clone_barrier();
153 };
154
155 // Metafunction mapping a class derived from BarrierSet to the
156 // corresponding Name enum tag.
157 template<typename T> struct BSTypeToName;
158 template<BarrierSet::Name T> struct BSNameToType;
159
160 template<typename T>
161 inline T* barrier_set_cast(BarrierSet* bs) {
162 assert(bs->is_a(BSTypeToName<T>::value), "wrong type of barrier set");
163 return static_cast<T*>(bs);
164 }
165
166 #endif // SHARE_VM_GC_SHARED_BARRIERSET_HPP