Mercurial > hg > truffle

comparison src/share/vm/oops/cpCacheOop.hpp @ 0:a61af66fc99e jdk7-b24

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Initial load
author duke
date Sat, 01 Dec 2007 00:00:00 +0000
parents
children ba764ed4b6f2
comparison
equal deleted inserted replaced
-1:000000000000 0:a61af66fc99e
1 /*
2 * Copyright 1998-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 // A ConstantPoolCacheEntry describes an individual entry of the constant
26 // pool cache. There's 2 principal kinds of entries: field entries for in-
27 // stance & static field access, and method entries for invokes. Some of
28 // the entry layout is shared and looks as follows:
29 //
30 // bit number |31 0|
31 // bit length |-8--|-8--|---16----|
32 // --------------------------------
33 // _indices [ b2 | b1 | index ]
34 // _f1 [ entry specific ]
35 // _f2 [ entry specific ]
36 // _flags [t|f|vf|v|m|h|unused|field_index] (for field entries)
37 // bit length |4|1|1 |1|1|0|---7--|----16-----]
38 // _flags [t|f|vf|v|m|h|unused|eidx|psze] (for method entries)
39 // bit length |4|1|1 |1|1|1|---7--|-8--|-8--]
40
41 // --------------------------------
42 //
43 // with:
44 // index = original constant pool index
45 // b1 = bytecode 1
46 // b2 = bytecode 2
47 // psze = parameters size (method entries only)
48 // eidx = interpreter entry index (method entries only)
49 // field_index = index into field information in holder instanceKlass
50 // The index max is 0xffff (max number of fields in constant pool)
51 // and is multiplied by (instanceKlass::next_offset) when accessing.
52 // t = TosState (see below)
53 // f = field is marked final (see below)
54 // vf = virtual, final (method entries only : is_vfinal())
55 // v = field is volatile (see below)
56 // m = invokeinterface used for method in class Object (see below)
57 // h = RedefineClasses/Hotswap bit (see below)
58 //
59 // The flags after TosState have the following interpretation:
60 // bit 27: f flag true if field is marked final
61 // bit 26: vf flag true if virtual final method
62 // bit 25: v flag true if field is volatile (only for fields)
63 // bit 24: m flag true if invokeinterface used for method in class Object
64 // bit 23: 0 for fields, 1 for methods
65 //
66 // The flags 31, 30, 29, 28 together build a 4 bit number 0 to 8 with the
67 // following mapping to the TosState states:
68 //
69 // btos: 0
70 // ctos: 1
71 // stos: 2
72 // itos: 3
73 // ltos: 4
74 // ftos: 5
75 // dtos: 6
76 // atos: 7
77 // vtos: 8
78 //
79 // Entry specific: field entries:
80 // _indices = get (b1 section) and put (b2 section) bytecodes, original constant pool index
81 // _f1 = field holder
82 // _f2 = field offset in words
83 // _flags = field type information, original field index in field holder
84 // (field_index section)
85 //
86 // Entry specific: method entries:
87 // _indices = invoke code for f1 (b1 section), invoke code for f2 (b2 section),
88 // original constant pool index
89 // _f1 = method for all but virtual calls, unused by virtual calls
90 // (note: for interface calls, which are essentially virtual,
91 // contains klassOop for the corresponding interface.
92 // _f2 = method/vtable index for virtual calls only, unused by all other
93 // calls. The vf flag indicates this is a method pointer not an
94 // index.
95 // _flags = field type info (f section),
96 // virtual final entry (vf),
97 // interpreter entry index (eidx section),
98 // parameter size (psze section)
99 //
100 // Note: invokevirtual & invokespecial bytecodes can share the same constant
101 // pool entry and thus the same constant pool cache entry. All invoke
102 // bytecodes but invokevirtual use only _f1 and the corresponding b1
103 // bytecode, while invokevirtual uses only _f2 and the corresponding
104 // b2 bytecode. The value of _flags is shared for both types of entries.
105 //
106 // The fields are volatile so that they are stored in the order written in the
107 // source code. The _indices field with the bytecode must be written last.
108
109 class ConstantPoolCacheEntry VALUE_OBJ_CLASS_SPEC {
110 friend class VMStructs;
111 private:
112 volatile intx _indices; // constant pool index & rewrite bytecodes
113 volatile oop _f1; // entry specific oop field
114 volatile intx _f2; // entry specific int/oop field
115 volatile intx _flags; // flags
116
117
118 #ifdef ASSERT
119 bool same_methodOop(oop cur_f1, oop f1);
120 #endif
121
122 void set_bytecode_1(Bytecodes::Code code);
123 void set_bytecode_2(Bytecodes::Code code);
124 void set_f1(oop f1) {
125 oop existing_f1 = _f1; // read once
126 assert(existing_f1 == NULL || existing_f1 == f1, "illegal field change");
127 oop_store(&_f1, f1);
128 }
129 void set_f2(intx f2) { assert(_f2 == 0 || _f2 == f2, "illegal field change"); _f2 = f2; }
130 int as_flags(TosState state, bool is_final, bool is_vfinal, bool is_volatile,
131 bool is_method_interface, bool is_method);
132 void set_flags(intx flags) { _flags = flags; }
133
134 public:
135 // specific bit values in flag field
136 // Note: the interpreter knows this layout!
137 enum FlagBitValues {
138 hotSwapBit = 23,
139 methodInterface = 24,
140 volatileField = 25,
141 vfinalMethod = 26,
142 finalField = 27
143 };
144
145 enum { field_index_mask = 0xFFFF };
146
147 // start of type bits in flags
148 // Note: the interpreter knows this layout!
149 enum FlagValues {
150 tosBits = 28
151 };
152
153 // Initialization
154 void set_initial_state(int index); // sets entry to initial state
155
156 void set_field( // sets entry to resolved field state
157 Bytecodes::Code get_code, // the bytecode used for reading the field
158 Bytecodes::Code put_code, // the bytecode used for writing the field
159 KlassHandle field_holder, // the object/klass holding the field
160 int orig_field_index, // the original field index in the field holder
161 int field_offset, // the field offset in words in the field holder
162 TosState field_type, // the (machine) field type
163 bool is_final, // the field is final
164 bool is_volatile // the field is volatile
165 );
166
167 void set_method( // sets entry to resolved method entry
168 Bytecodes::Code invoke_code, // the bytecode used for invoking the method
169 methodHandle method, // the method/prototype if any (NULL, otherwise)
170 int vtable_index // the vtable index if any, else negative
171 );
172
173 void set_interface_call(
174 methodHandle method, // Resolved method
175 int index // Method index into interface
176 );
177
178 void set_parameter_size(int value) {
179 assert(parameter_size() == 0 || parameter_size() == value,
180 "size must not change");
181 // Setting the parameter size by itself is only safe if the
182 // current value of _flags is 0, otherwise another thread may have
183 // updated it and we don't want to overwrite that value. Don't
184 // bother trying to update it once it's nonzero but always make
185 // sure that the final parameter size agrees with what was passed.
186 if (_flags == 0) {
187 Atomic::cmpxchg_ptr((value & 0xFF), &_flags, 0);
188 }
189 guarantee(parameter_size() == value, "size must not change");
190 }
191
192 // Which bytecode number (1 or 2) in the index field is valid for this bytecode?
193 // Returns -1 if neither is valid.
194 static int bytecode_number(Bytecodes::Code code) {
195 switch (code) {
196 case Bytecodes::_getstatic : // fall through
197 case Bytecodes::_getfield : // fall through
198 case Bytecodes::_invokespecial : // fall through
199 case Bytecodes::_invokestatic : // fall through
200 case Bytecodes::_invokeinterface : return 1;
201 case Bytecodes::_putstatic : // fall through
202 case Bytecodes::_putfield : // fall through
203 case Bytecodes::_invokevirtual : return 2;
204 default : break;
205 }
206 return -1;
207 }
208
209 // Has this bytecode been resolved? Only valid for invokes and get/put field/static.
210 bool is_resolved(Bytecodes::Code code) const {
211 switch (bytecode_number(code)) {
212 case 1: return (bytecode_1() == code);
213 case 2: return (bytecode_2() == code);
214 }
215 return false; // default: not resolved
216 }
217
218 // Accessors
219 int constant_pool_index() const { return _indices & 0xFFFF; }
220 Bytecodes::Code bytecode_1() const { return Bytecodes::cast((_indices >> 16) & 0xFF); }
221 Bytecodes::Code bytecode_2() const { return Bytecodes::cast((_indices >> 24) & 0xFF); }
222 volatile oop f1() const { return _f1; }
223 intx f2() const { return _f2; }
224 int field_index() const;
225 int parameter_size() const { return _flags & 0xFF; }
226 bool is_vfinal() const { return ((_flags & (1 << vfinalMethod)) == (1 << vfinalMethod)); }
227 bool is_volatile() const { return ((_flags & (1 << volatileField)) == (1 << volatileField)); }
228 bool is_methodInterface() const { return ((_flags & (1 << methodInterface)) == (1 << methodInterface)); }
229 bool is_byte() const { return (((uintx) _flags >> tosBits) == btos); }
230 bool is_char() const { return (((uintx) _flags >> tosBits) == ctos); }
231 bool is_short() const { return (((uintx) _flags >> tosBits) == stos); }
232 bool is_int() const { return (((uintx) _flags >> tosBits) == itos); }
233 bool is_long() const { return (((uintx) _flags >> tosBits) == ltos); }
234 bool is_float() const { return (((uintx) _flags >> tosBits) == ftos); }
235 bool is_double() const { return (((uintx) _flags >> tosBits) == dtos); }
236 bool is_object() const { return (((uintx) _flags >> tosBits) == atos); }
237 TosState flag_state() const { assert( ( (_flags >> tosBits) & 0x0F ) < number_of_states, "Invalid state in as_flags");
238 return (TosState)((_flags >> tosBits) & 0x0F); }
239
240 // Code generation support
241 static WordSize size() { return in_WordSize(sizeof(ConstantPoolCacheEntry) / HeapWordSize); }
242 static ByteSize indices_offset() { return byte_offset_of(ConstantPoolCacheEntry, _indices); }
243 static ByteSize f1_offset() { return byte_offset_of(ConstantPoolCacheEntry, _f1); }
244 static ByteSize f2_offset() { return byte_offset_of(ConstantPoolCacheEntry, _f2); }
245 static ByteSize flags_offset() { return byte_offset_of(ConstantPoolCacheEntry, _flags); }
246
247 // GC Support
248 void oops_do(void f(oop*));
249 void oop_iterate(OopClosure* blk);
250 void oop_iterate_m(OopClosure* blk, MemRegion mr);
251 void follow_contents();
252 void adjust_pointers();
253
254 #ifndef SERIALGC
255 // Parallel Old
256 void follow_contents(ParCompactionManager* cm);
257 #endif // SERIALGC
258
259 void update_pointers();
260 void update_pointers(HeapWord* beg_addr, HeapWord* end_addr);
261
262 // RedefineClasses() API support:
263 // If this constantPoolCacheEntry refers to old_method then update it
264 // to refer to new_method.
265 // trace_name_printed is set to true if the current call has
266 // printed the klass name so that other routines in the adjust_*
267 // group don't print the klass name.
268 bool adjust_method_entry(methodOop old_method, methodOop new_method,
269 bool * trace_name_printed);
270 bool is_interesting_method_entry(klassOop k);
271 bool is_field_entry() const { return (_flags & (1 << hotSwapBit)) == 0; }
272 bool is_method_entry() const { return (_flags & (1 << hotSwapBit)) != 0; }
273
274 // Debugging & Printing
275 void print (outputStream* st, int index) const;
276 void verify(outputStream* st) const;
277
278 static void verify_tosBits() {
279 assert(tosBits == 28, "interpreter now assumes tosBits is 28");
280 }
281 };
282
283
284 // A constant pool cache is a runtime data structure set aside to a constant pool. The cache
285 // holds interpreter runtime information for all field access and invoke bytecodes. The cache
286 // is created and initialized before a class is actively used (i.e., initialized), the indivi-
287 // dual cache entries are filled at resolution (i.e., "link") time (see also: rewriter.*).
288
289 class constantPoolCacheOopDesc: public arrayOopDesc {
290 friend class VMStructs;
291 private:
292 constantPoolOop _constant_pool; // the corresponding constant pool
293
294 // Sizing
295 static int header_size() { return sizeof(constantPoolCacheOopDesc) / HeapWordSize; }
296 static int object_size(int length) { return align_object_size(header_size() + length * in_words(ConstantPoolCacheEntry::size())); }
297 int object_size() { return object_size(length()); }
298
299 // Helpers
300 constantPoolOop* constant_pool_addr() { return &_constant_pool; }
301 ConstantPoolCacheEntry* base() const { return (ConstantPoolCacheEntry*)((address)this + in_bytes(base_offset())); }
302
303 friend class constantPoolCacheKlass;
304
305 public:
306 // Initialization
307 void initialize(intArray& inverse_index_map);
308
309 // Accessors
310 void set_constant_pool(constantPoolOop pool) { oop_store_without_check((oop*)&_constant_pool, (oop)pool); }
311 constantPoolOop constant_pool() const { return _constant_pool; }
312 ConstantPoolCacheEntry* entry_at(int i) const { assert(0 <= i && i < length(), "index out of bounds"); return base() + i; }
313
314 // Code generation
315 static ByteSize base_offset() { return in_ByteSize(sizeof(constantPoolCacheOopDesc)); }
316
317 // RedefineClasses() API support:
318 // If any entry of this constantPoolCache points to any of
319 // old_methods, replace it with the corresponding new_method.
320 // trace_name_printed is set to true if the current call has
321 // printed the klass name so that other routines in the adjust_*
322 // group don't print the klass name.
323 void adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
324 int methods_length, bool * trace_name_printed);
325 };