1 /*
2 * Copyright (c) 2017, 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_VALUEKLASS_HPP
26 #define SHARE_VM_OOPS_VALUEKLASS_HPP
27
28 #include "classfile/javaClasses.hpp"
29 #include "oops/instanceKlass.hpp"
30 #include "oops/method.hpp"
31 #include "oops/oop.inline.hpp"
32
33 // A ValueKlass is a specialized InstanceKlass for value types.
34
35
36 class ValueKlass: public InstanceKlass {
37 friend class VMStructs;
38 friend class InstanceKlass;
39
40 private:
41
42 // Constructor
43 ValueKlass(const ClassFileParser& parser)
44 : InstanceKlass(parser, InstanceKlass::_misc_kind_value_type, InstanceKlass::ID) {
45 _adr_valueklass_fixed_block = valueklass_static_block();
46 // Addresses used for value type calling convention
47 *((Array<SigEntry>**)adr_extended_sig()) = NULL;
48 *((Array<VMRegPair>**)adr_return_regs()) = NULL;
49 *((address*)adr_pack_handler()) = NULL;
50 *((address*)adr_unpack_handler()) = NULL;
51 assert(pack_handler() == NULL, "pack handler not null");
52 *((int*)adr_default_value_offset()) = 0;
53 set_prototype_header(markOopDesc::always_locked_prototype());
54 }
55
56 ValueKlassFixedBlock* valueklass_static_block() const {
57 address adr_jf = adr_value_fields_klasses();
58 if (adr_jf != NULL) {
59 return (ValueKlassFixedBlock*)(adr_jf + this->java_fields_count() * sizeof(Klass*));
60 }
61
62 address adr_fing = adr_fingerprint();
63 if (adr_fing != NULL) {
64 return (ValueKlassFixedBlock*)(adr_fingerprint() + sizeof(u8));
65 }
66
67 InstanceKlass** adr_host = adr_unsafe_anonymous_host();
68 if (adr_host != NULL) {
69 return (ValueKlassFixedBlock*)(adr_host + 1);
70 }
71
72 Klass* volatile* adr_impl = adr_implementor();
73 if (adr_impl != NULL) {
74 return (ValueKlassFixedBlock*)(adr_impl + 1);
75 }
76
77 return (ValueKlassFixedBlock*)end_of_nonstatic_oop_maps();
78 }
79
80 address adr_extended_sig() const {
81 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
82 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _extended_sig));
83 }
84
85 address adr_return_regs() const {
86 ValueKlassFixedBlock* vkst = valueklass_static_block();
87 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _return_regs));
88 }
89
90 // pack and unpack handlers for value types return
91 address adr_pack_handler() const {
92 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
93 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _pack_handler));
94 }
95
96 address adr_unpack_handler() const {
97 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
98 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _unpack_handler));
99 }
100
101 address pack_handler() const {
102 return *(address*)adr_pack_handler();
103 }
104
105 address unpack_handler() const {
106 return *(address*)adr_unpack_handler();
107 }
108
109 address adr_default_value_offset() const {
110 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
111 return ((address)_adr_valueklass_fixed_block) + in_bytes(default_value_offset_offset());
112 }
113
114 int collect_fields(GrowableArray<SigEntry>* sig, int base_off = 0) const;
115
116 void cleanup_blobs();
117
118 protected:
119 // Returns the array class for the n'th dimension
120 Klass* array_klass_impl(bool or_null, int n, TRAPS);
121
122 // Returns the array class with this class as element type
123 Klass* array_klass_impl(bool or_null, TRAPS);
124
125 public:
126 // Type testing
127 bool is_value_slow() const { return true; }
128
129 oop value_mirror() const {
130 return java_lang_Class::value_mirror(java_mirror());
131 }
132
133 // Casting from Klass*
134 static ValueKlass* cast(Klass* k) {
135 assert(k->is_value(), "cast to ValueKlass");
136 return (ValueKlass*) k;
137 }
138
139 // Use this to return the size of an instance in heap words
140 // Implementation is currently simple because all value types are allocated
141 // in Java heap like Java objects.
142 virtual int size_helper() const {
143 return layout_helper_to_size_helper(layout_helper());
144 }
145
146 // allocate_instance() allocates a stand alone value in the Java heap
147 instanceOop allocate_instance(TRAPS);
148
149 // minimum number of bytes occupied by nonstatic fields, HeapWord aligned or pow2
150 int raw_value_byte_size() const;
151
152 int first_field_offset() const;
153
154 address data_for_oop(oop o) const {
155 return ((address) (void*) o) + first_field_offset();
156 }
157
158 oop oop_for_data(address data) const {
159 oop o = (oop) (data - first_field_offset());
160 assert(oopDesc::is_oop(o, false), "Not an oop");
161 return o;
162 }
163
164 // Query if h/w provides atomic load/store
165 bool is_atomic();
166
167 bool flatten_array();
168
169 bool contains_oops() const { return nonstatic_oop_map_count() > 0; }
170 int nonstatic_oop_count();
171
172 // Prototype general store methods...
173
174 // copy the fields, with no concern for GC barriers
175 void raw_field_copy(void* src, void* dst, size_t raw_byte_size);
176
177 void value_store(void* src, void* dst, bool dst_is_heap, bool dst_uninitialized) {
178 value_store(src, dst, nonstatic_field_size() << LogBytesPerHeapOop, dst_is_heap, dst_uninitialized);
179 }
180
181 // store the value of this klass contained with src into dst, raw data ptr
182 void value_store(void* src, void* dst, size_t raw_byte_size, bool dst_is_heap, bool dst_uninitialized);
183
184 // GC support...
185
186 void iterate_over_inside_oops(OopClosure* f, oop value);
187
188 // oop iterate raw value type data pointer (where oop_addr may not be an oop, but backing/array-element)
189 template <typename T, class OopClosureType>
190 inline void oop_iterate_specialized(const address oop_addr, OopClosureType* closure);
191
192 template <typename T, class OopClosureType>
193 inline void oop_iterate_specialized_bounded(const address oop_addr, OopClosureType* closure, void* lo, void* hi);
194
195 // calling convention support
196 void initialize_calling_convention(TRAPS);
197 Array<SigEntry>* extended_sig() const {
198 return *((Array<SigEntry>**)adr_extended_sig());
199 }
200 Array<VMRegPair>* return_regs() const {
201 return *((Array<VMRegPair>**)adr_return_regs());
202 }
203 bool can_be_returned_as_fields() const;
204 void save_oop_fields(const RegisterMap& map, GrowableArray<Handle>& handles) const;
205 void restore_oop_results(RegisterMap& map, GrowableArray<Handle>& handles) const;
206 oop realloc_result(const RegisterMap& reg_map, const GrowableArray<Handle>& handles, TRAPS);
207 static ValueKlass* returned_value_klass(const RegisterMap& reg_map);
208
209 // pack and unpack handlers. Need to be loadable from generated code
210 // so at a fixed offset from the base of the klass pointer.
211 static ByteSize pack_handler_offset() {
212 return byte_offset_of(ValueKlassFixedBlock, _pack_handler);
213 }
214
215 static ByteSize unpack_handler_offset() {
216 return byte_offset_of(ValueKlassFixedBlock, _unpack_handler);
217 }
218
219 static ByteSize default_value_offset_offset() {
220 return byte_offset_of(ValueKlassFixedBlock, _default_value_offset);
221 }
222
223 void set_default_value_offset(int offset) {
224 *((int*)adr_default_value_offset()) = offset;
225 }
226
227 int default_value_offset() {
228 int offset = *((int*)adr_default_value_offset());
229 assert(offset != 0, "must not be called if not initialized");
230 return offset;
231 }
232
233 void set_default_value(oop val) {
234 java_mirror()->obj_field_put(default_value_offset(), val);
235 }
236
237 oop default_value() {
238 oop val = java_mirror()->obj_field_acquire(default_value_offset());
239 assert(oopDesc::is_oop(val), "Sanity check");
240 assert(val->is_value(), "Sanity check");
241 assert(val->klass() == this, "sanity check");
242 return val;
243 }
244
245 void deallocate_contents(ClassLoaderData* loader_data);
246 static void cleanup(ValueKlass* ik) ;
247
248 // Verification
249 void verify_on(outputStream* st);
250 void oop_verify_on(oop obj, outputStream* st);
251
252 };
253
254 #endif /* SHARE_VM_OOPS_VALUEKLASS_HPP */