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 "oops/instanceKlass.hpp"
29 #include "oops/method.hpp"
30 #include "oops/oop.inline.hpp"
31
32 // A ValueKlass is a specialized InstanceKlass for value types.
33
34
35 class ValueKlass: public InstanceKlass {
36 friend class VMStructs;
37 friend class InstanceKlass;
38
39 private:
40
41 // Constructor
42 ValueKlass(const ClassFileParser& parser)
43 : InstanceKlass(parser, InstanceKlass::_misc_kind_value_type) {
44 _adr_valueklass_fixed_block = valueklass_static_bloc();
45 // Addresses used for value type calling convention
46 *((Array<SigEntry>**)adr_extended_sig()) = NULL;
47 *((Array<VMRegPair>**)adr_return_regs()) = NULL;
48 *((address*)adr_pack_handler()) = NULL;
49 *((address*)adr_unpack_handler()) = NULL;
50 assert(pack_handler() == NULL, "pack handler not null");
51 *((int*)adr_default_value_offset()) = 0;
52
53 }
54
55 ValueKlassFixedBlock* valueklass_static_bloc() const {
56 address adr_jf = adr_value_fields_klasses();
57 if (adr_jf != NULL) {
58 return (ValueKlassFixedBlock*)(adr_jf + this->java_fields_count() * sizeof(Klass*));
59 }
60
61 address adr_fing = adr_fingerprint();
62 if (adr_fing != NULL) {
63 return (ValueKlassFixedBlock*)(adr_fingerprint() + sizeof(u8));
64 }
65
66 InstanceKlass** adr_host = adr_host_klass();
67 if (adr_host != NULL) {
68 return (ValueKlassFixedBlock*)(adr_host + 1);
69 }
70
71 Klass** adr_impl = adr_implementor();
72 if (adr_impl != NULL) {
73 return (ValueKlassFixedBlock*)(adr_impl + 1);
74 }
75
76 return (ValueKlassFixedBlock*)end_of_nonstatic_oop_maps();
77 }
78
79 address adr_extended_sig() const {
80 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
81 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _extended_sig));
82 }
83
84 address adr_return_regs() const {
85 ValueKlassFixedBlock* vkst = valueklass_static_bloc();
86 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _return_regs));
87 }
88
89 // pack and unpack handlers for value types return
90 address adr_pack_handler() const {
91 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
92 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _pack_handler));
93 }
94
95 address adr_unpack_handler() const {
96 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
97 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _unpack_handler));
98 }
99
100 address pack_handler() const {
101 return *(address*)adr_pack_handler();
102 }
103
104 address unpack_handler() const {
105 return *(address*)adr_unpack_handler();
106 }
107
108 address adr_default_value_offset() const {
109 assert(_adr_valueklass_fixed_block != NULL, "Should have been initialized");
110 return ((address)_adr_valueklass_fixed_block) + in_bytes(byte_offset_of(ValueKlassFixedBlock, _default_value_offset));
111 }
112
113 // static Klass* array_klass_impl(InstanceKlass* this_k, bool or_null, int n, TRAPS);
114
115 GrowableArray<SigEntry> collect_fields(int base_off = 0) const;
116
117 void cleanup_blobs();
118
119 protected:
120 // Returns the array class for the n'th dimension
121 Klass* array_klass_impl(bool or_null, int n, TRAPS);
122
123 // Returns the array class with this class as element type
124 Klass* array_klass_impl(bool or_null, TRAPS);
125
126 public:
127 // Type testing
128 bool is_value_slow() const { return true; }
129
130 // Casting from Klass*
131 static ValueKlass* cast(Klass* k) {
132 assert(k->is_value(), "cast to ValueKlass");
133 return (ValueKlass*) k;
134 }
135
136 // Use this to return the size of an instance in heap words
137 // Implementation is currently simple because all value types are allocated
138 // in Java heap like Java objects.
139 virtual int size_helper() const {
140 return layout_helper_to_size_helper(layout_helper());
141 }
142
143 // allocate_instance() allocates a stand alone value in the Java heap
144 instanceOop allocate_instance(TRAPS);
145 // allocate_buffered_or_heap_instance() tries to allocate a value in the
146 // thread local value buffer, if allocation fails, it allocates it in the
147 // Java heap
148 instanceOop allocate_buffered_or_heap_instance(bool* in_heap, TRAPS);
149
150 // minimum number of bytes occupied by nonstatic fields, HeapWord aligned or pow2
151 int raw_value_byte_size() const;
152
153 int first_field_offset() const;
154
155 address data_for_oop(oop o) const {
156 return ((address) (void*) o) + first_field_offset();
157 }
158
159 oop oop_for_data(address data) const {
160 oop o = (oop) (data - first_field_offset());
161 assert(oopDesc::is_oop(o, false), "Not an oop");
162 return o;
163 }
164
165 void set_if_bufferable() {
166 bool bufferable;
167
168 int size_in_heap_words = size_helper();
169 int base_offset = instanceOopDesc::base_offset_in_bytes();
170 size_t size_in_bytes = size_in_heap_words * HeapWordSize - base_offset;
171 bufferable = size_in_bytes <= BigValueTypeThreshold;
172 if (size_in_bytes > VTBufferChunk::max_alloc_size()) bufferable = false;
173 if (ValueTypesBufferMaxMemory == 0) bufferable = false;
174
175 if (bufferable) {
176 _extra_flags |= _extra_is_bufferable;
177 } else {
178 _extra_flags &= ~_extra_is_bufferable;
179 }
180 }
181
182 bool is_bufferable() const {
183 return (_extra_flags & _extra_is_bufferable) != 0;
184 }
185
186 // Query if h/w provides atomic load/store
187 bool is_atomic();
188
189 bool flatten_array();
190
191 bool contains_oops() const { return nonstatic_oop_map_count() > 0; }
192 int nonstatic_oop_count();
193
194 // Prototype general store methods...
195
196 // copy the fields, with no concern for GC barriers
197 void raw_field_copy(void* src, void* dst, size_t raw_byte_size);
198
199 void value_store(void* src, void* dst, bool dst_is_heap, bool dst_uninitialized) {
200 value_store(src, dst, nonstatic_field_size() << LogBytesPerHeapOop, dst_is_heap, dst_uninitialized);
201 }
202
203 // store the value of this klass contained with src into dst, raw data ptr
204 void value_store(void* src, void* dst, size_t raw_byte_size, bool dst_is_heap, bool dst_uninitialized);
205
206 // GC support...
207
208 void iterate_over_inside_oops(OopClosure* f, oop value);
209
210 // oop iterate raw value type data pointer (where oop_addr may not be an oop, but backing/array-element)
211 template <bool nv, typename T, class OopClosureType>
212 inline void oop_iterate_specialized(const address oop_addr, OopClosureType* closure);
213
214 template <bool nv, typename T, class OopClosureType>
215 inline void oop_iterate_specialized_bounded(const address oop_addr, OopClosureType* closure, void* lo, void* hi);
216
217 // calling convention support
218 void initialize_calling_convention();
219 Array<SigEntry>* extended_sig() const {
220 return *((Array<SigEntry>**)adr_extended_sig());
221 }
222 Array<VMRegPair>* return_regs() const {
223 return *((Array<VMRegPair>**)adr_return_regs());
224 }
225 bool can_be_returned_as_fields() const;
226 void save_oop_fields(const RegisterMap& map, GrowableArray<Handle>& handles) const;
227 void restore_oop_results(RegisterMap& map, GrowableArray<Handle>& handles) const;
228 oop realloc_result(const RegisterMap& reg_map, const GrowableArray<Handle>& handles, bool buffered, TRAPS);
229 static ValueKlass* returned_value_klass(const RegisterMap& reg_map);
230
231 // pack and unpack handlers. Need to be loadable from generated code
232 // so at a fixed offset from the base of the klass pointer.
233 static ByteSize pack_handler_offset() {
234 fatal("Should be re-implemented using the ValueKlassStaticBlock indirection");
235 return in_ByteSize(InstanceKlass::header_size() * wordSize);
236 }
237
238 static ByteSize unpack_handler_offset() {
239 fatal("Should be re-implemented using the ValueKlassStaticBlock indirection");
240 return in_ByteSize((InstanceKlass::header_size()+1) * wordSize);
241 }
242
243 static ByteSize default_value_offset_offset() {
244 fatal("Should be re-implemented using the ValueKlassStaticBlock indirection");
245 return in_ByteSize((InstanceKlass::header_size()+2) * wordSize);
246 }
247
248 void set_default_value_offset(int offset) {
249 *((int*)adr_default_value_offset()) = offset;
250 }
251
252 int default_value_offset() {
253 int offset = *((int*)adr_default_value_offset());
254 assert(offset != 0, "must not be called if not initialized");
255 return offset;
256 }
257
258 void set_default_value(oop val) {
259 java_mirror()->obj_field_put(default_value_offset(), val);
260 }
261
262 oop default_value() {
263 oop val = java_mirror()->obj_field_acquire(default_value_offset());
264 assert(oopDesc::is_oop(val), "Sanity check");
265 assert(val->is_value(), "Sanity check");
266 assert(val->klass() == this, "sanity check");
267 return val;
268 }
269
270 void deallocate_contents(ClassLoaderData* loader_data);
271 static void cleanup(ValueKlass* ik) ;
272 };
273
274 #endif /* SHARE_VM_OOPS_VALUEKLASS_HPP */