Sat, 29 Sep 2012 06:40:00 -0400
8000213: NPG: Should have renamed arrayKlass and typeArrayKlass
Summary: Capitalize these metadata types (and objArrayKlass)
Reviewed-by: stefank, twisti, kvn
1 /*
2 * Copyright (c) 1997, 2012, 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
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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 */
25 #ifndef SHARE_VM_OOPS_KLASSVTABLE_HPP
26 #define SHARE_VM_OOPS_KLASSVTABLE_HPP
28 #include "memory/allocation.hpp"
29 #include "oops/oopsHierarchy.hpp"
30 #include "runtime/handles.hpp"
31 #include "utilities/growableArray.hpp"
33 // A klassVtable abstracts the variable-length vtable that is embedded in InstanceKlass
34 // and ArrayKlass. klassVtable objects are used just as convenient transient accessors to the vtable,
35 // not to actually hold the vtable data.
36 // Note: the klassVtable should not be accessed before the class has been verified
37 // (until that point, the vtable is uninitialized).
39 // Currently a klassVtable contains a direct reference to the vtable data, and is therefore
40 // not preserved across GCs.
42 class vtableEntry;
44 class klassVtable : public ResourceObj {
45 KlassHandle _klass; // my klass
46 int _tableOffset; // offset of start of vtable data within klass
47 int _length; // length of vtable (number of entries)
48 #ifndef PRODUCT
49 int _verify_count; // to make verify faster
50 #endif
52 // Ordering important, so greater_than (>) can be used as an merge operator.
53 enum AccessType {
54 acc_private = 0,
55 acc_package_private = 1,
56 acc_publicprotected = 2
57 };
59 public:
60 klassVtable(KlassHandle h_klass, void* base, int length) : _klass(h_klass) {
61 _tableOffset = (address)base - (address)h_klass(); _length = length;
62 }
64 // accessors
65 vtableEntry* table() const { return (vtableEntry*)(address(_klass()) + _tableOffset); }
66 KlassHandle klass() const { return _klass; }
67 int length() const { return _length; }
68 inline Method* method_at(int i) const;
69 inline Method* unchecked_method_at(int i) const;
70 inline Method** adr_method_at(int i) const;
72 // searching; all methods return -1 if not found
73 int index_of(Method* m) const { return index_of(m, _length); }
74 int index_of_miranda(Symbol* name, Symbol* signature);
76 void initialize_vtable(bool checkconstraints, TRAPS); // initialize vtable of a new klass
78 // CDS/RedefineClasses support - clear vtables so they can be reinitialized
79 // at dump time. Clearing gives us an easy way to tell if the vtable has
80 // already been reinitialized at dump time (see dump.cpp). Vtables can
81 // be initialized at run time by RedefineClasses so dumping the right order
82 // is necessary.
83 void clear_vtable();
84 bool is_initialized();
86 // computes vtable length (in words) and the number of miranda methods
87 static void compute_vtable_size_and_num_mirandas(int &vtable_length, int &num_miranda_methods,
88 Klass* super, Array<Method*>* methods,
89 AccessFlags class_flags, Handle classloader,
90 Symbol* classname, Array<Klass*>* local_interfaces,
91 TRAPS);
93 // RedefineClasses() API support:
94 // If any entry of this vtable points to any of old_methods,
95 // replace it with the corresponding new_method.
96 // trace_name_printed is set to true if the current call has
97 // printed the klass name so that other routines in the adjust_*
98 // group don't print the klass name.
99 void adjust_method_entries(Method** old_methods, Method** new_methods,
100 int methods_length, bool * trace_name_printed);
102 // Debugging code
103 void print() PRODUCT_RETURN;
104 void verify(outputStream* st, bool force = false);
105 static void print_statistics() PRODUCT_RETURN;
107 #ifndef PRODUCT
108 bool check_no_old_entries();
109 void dump_vtable();
110 #endif
112 protected:
113 friend class vtableEntry;
114 private:
115 enum { VTABLE_TRANSITIVE_OVERRIDE_VERSION = 51 } ;
116 void copy_vtable_to(vtableEntry* start);
117 int initialize_from_super(KlassHandle super);
118 int index_of(Method* m, int len) const; // same as index_of, but search only up to len
119 void put_method_at(Method* m, int index);
120 static bool needs_new_vtable_entry(methodHandle m, Klass* super, Handle classloader, Symbol* classname, AccessFlags access_flags, TRAPS);
122 bool update_inherited_vtable(InstanceKlass* klass, methodHandle target_method, int super_vtable_len, bool checkconstraints, TRAPS);
123 InstanceKlass* find_transitive_override(InstanceKlass* initialsuper, methodHandle target_method, int vtable_index,
124 Handle target_loader, Symbol* target_classname, Thread* THREAD);
126 // support for miranda methods
127 bool is_miranda_entry_at(int i);
128 void fill_in_mirandas(int& initialized);
129 static bool is_miranda(Method* m, Array<Method*>* class_methods, Klass* super);
130 static void add_new_mirandas_to_list(GrowableArray<Method*>* list_of_current_mirandas, Array<Method*>* current_interface_methods, Array<Method*>* class_methods, Klass* super);
131 static void get_mirandas(GrowableArray<Method*>* mirandas, Klass* super, Array<Method*>* class_methods, Array<Klass*>* local_interfaces);
132 static int get_num_mirandas(Klass* super, Array<Method*>* class_methods, Array<Klass*>* local_interfaces);
135 void verify_against(outputStream* st, klassVtable* vt, int index);
136 inline InstanceKlass* ik() const;
137 };
140 // private helper class for klassVtable
141 // description of entry points:
142 // destination is interpreted:
143 // from_compiled_code_entry_point -> c2iadapter
144 // from_interpreter_entry_point -> interpreter entry point
145 // destination is compiled:
146 // from_compiled_code_entry_point -> nmethod entry point
147 // from_interpreter_entry_point -> i2cadapter
148 class vtableEntry VALUE_OBJ_CLASS_SPEC {
149 public:
150 // size in words
151 static int size() {
152 return sizeof(vtableEntry) / sizeof(HeapWord);
153 }
154 static int method_offset_in_bytes() { return offset_of(vtableEntry, _method); }
155 Method* method() const { return _method; }
157 private:
158 Method* _method;
159 void set(Method* method) { assert(method != NULL, "use clear"); _method = method; }
160 void clear() { _method = NULL; }
161 void print() PRODUCT_RETURN;
162 void verify(klassVtable* vt, outputStream* st);
164 friend class klassVtable;
165 };
168 inline Method* klassVtable::method_at(int i) const {
169 assert(i >= 0 && i < _length, "index out of bounds");
170 assert(table()[i].method() != NULL, "should not be null");
171 assert(((Metadata*)table()[i].method())->is_method(), "should be method");
172 return table()[i].method();
173 }
175 inline Method* klassVtable::unchecked_method_at(int i) const {
176 assert(i >= 0 && i < _length, "index out of bounds");
177 return table()[i].method();
178 }
180 inline Method** klassVtable::adr_method_at(int i) const {
181 // Allow one past the last entry to be referenced; useful for loop bounds.
182 assert(i >= 0 && i <= _length, "index out of bounds");
183 return (Method**)(address(table() + i) + vtableEntry::method_offset_in_bytes());
184 }
186 // --------------------------------------------------------------------------------
187 class klassItable;
188 class itableMethodEntry;
190 class itableOffsetEntry VALUE_OBJ_CLASS_SPEC {
191 private:
192 Klass* _interface;
193 int _offset;
194 public:
195 Klass* interface_klass() const { return _interface; }
196 int offset() const { return _offset; }
198 static itableMethodEntry* method_entry(Klass* k, int offset) { return (itableMethodEntry*)(((address)k) + offset); }
199 itableMethodEntry* first_method_entry(Klass* k) { return method_entry(k, _offset); }
201 void initialize(Klass* interf, int offset) { _interface = interf; _offset = offset; }
203 // Static size and offset accessors
204 static int size() { return sizeof(itableOffsetEntry) / HeapWordSize; } // size in words
205 static int interface_offset_in_bytes() { return offset_of(itableOffsetEntry, _interface); }
206 static int offset_offset_in_bytes() { return offset_of(itableOffsetEntry, _offset); }
208 friend class klassItable;
209 };
212 class itableMethodEntry VALUE_OBJ_CLASS_SPEC {
213 private:
214 Method* _method;
216 public:
217 Method* method() const { return _method; }
219 void clear() { _method = NULL; }
221 void initialize(Method* method);
223 // Static size and offset accessors
224 static int size() { return sizeof(itableMethodEntry) / HeapWordSize; } // size in words
225 static int method_offset_in_bytes() { return offset_of(itableMethodEntry, _method); }
227 friend class klassItable;
228 };
230 //
231 // Format of an itable
232 //
233 // ---- offset table ---
234 // Klass* of interface 1 \
235 // offset to vtable from start of oop / offset table entry
236 // ...
237 // Klass* of interface n \
238 // offset to vtable from start of oop / offset table entry
239 // --- vtable for interface 1 ---
240 // Method* \
241 // compiler entry point / method table entry
242 // ...
243 // Method* \
244 // compiler entry point / method table entry
245 // -- vtable for interface 2 ---
246 // ...
247 //
248 class klassItable : public ResourceObj {
249 private:
250 instanceKlassHandle _klass; // my klass
251 int _table_offset; // offset of start of itable data within klass (in words)
252 int _size_offset_table; // size of offset table (in itableOffset entries)
253 int _size_method_table; // size of methodtable (in itableMethodEntry entries)
255 void initialize_itable_for_interface(int method_table_offset, KlassHandle interf_h, bool checkconstraints, TRAPS);
256 public:
257 klassItable(instanceKlassHandle klass);
259 itableOffsetEntry* offset_entry(int i) { assert(0 <= i && i <= _size_offset_table, "index out of bounds");
260 return &((itableOffsetEntry*)vtable_start())[i]; }
262 itableMethodEntry* method_entry(int i) { assert(0 <= i && i <= _size_method_table, "index out of bounds");
263 return &((itableMethodEntry*)method_start())[i]; }
265 int size_offset_table() { return _size_offset_table; }
267 // Initialization
268 void initialize_itable(bool checkconstraints, TRAPS);
270 // Updates
271 void initialize_with_method(Method* m);
273 // RedefineClasses() API support:
274 // if any entry of this itable points to any of old_methods,
275 // replace it with the corresponding new_method.
276 // trace_name_printed is set to true if the current call has
277 // printed the klass name so that other routines in the adjust_*
278 // group don't print the klass name.
279 void adjust_method_entries(Method** old_methods, Method** new_methods,
280 int methods_length, bool * trace_name_printed);
282 // Setup of itable
283 static int compute_itable_size(Array<Klass*>* transitive_interfaces);
284 static void setup_itable_offset_table(instanceKlassHandle klass);
286 // Resolving of method to index
287 static int compute_itable_index(Method* m);
288 // ...and back again:
289 static Method* method_for_itable_index(Klass* klass, int itable_index);
291 // Debugging/Statistics
292 static void print_statistics() PRODUCT_RETURN;
293 private:
294 intptr_t* vtable_start() const { return ((intptr_t*)_klass()) + _table_offset; }
295 intptr_t* method_start() const { return vtable_start() + _size_offset_table * itableOffsetEntry::size(); }
297 // Helper methods
298 static int calc_itable_size(int num_interfaces, int num_methods) { return (num_interfaces * itableOffsetEntry::size()) + (num_methods * itableMethodEntry::size()); }
300 // Statistics
301 NOT_PRODUCT(static int _total_classes;) // Total no. of classes with itables
302 NOT_PRODUCT(static long _total_size;) // Total no. of bytes used for itables
304 static void update_stats(int size) PRODUCT_RETURN NOT_PRODUCT({ _total_classes++; _total_size += size; })
306 public:
307 #ifndef PRODUCT
308 bool check_no_old_entries();
309 #endif
310 };
312 #endif // SHARE_VM_OOPS_KLASSVTABLE_HPP