Tue, 28 Jul 2009 12:12:40 -0700
6862919: Update copyright year
Summary: Update copyright for files that have been modified in 2009, up to 07/09
Reviewed-by: tbell, ohair
1 /*
2 * Copyright 1997-2009 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 */
25 // A constantPool is an array containing class constants as described in the
26 // class file.
27 //
28 // Most of the constant pool entries are written during class parsing, which
29 // is safe. For klass and string types, the constant pool entry is
30 // modified when the entry is resolved. If a klass or string constant pool
31 // entry is read without a lock, only the resolved state guarantees that
32 // the entry in the constant pool is a klass or String object and
33 // not a symbolOop.
35 class SymbolHashMap;
37 class constantPoolOopDesc : public oopDesc {
38 friend class VMStructs;
39 friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast
40 private:
41 typeArrayOop _tags; // the tag array describing the constant pool's contents
42 constantPoolCacheOop _cache; // the cache holding interpreter runtime information
43 klassOop _pool_holder; // the corresponding class
44 int _flags; // a few header bits to describe contents for GC
45 int _length; // number of elements in the array
46 volatile bool _is_conc_safe; // if true, safe for concurrent
47 // GC processing
48 // only set to non-zero if constant pool is merged by RedefineClasses
49 int _orig_length;
51 void set_tags(typeArrayOop tags) { oop_store_without_check((oop*)&_tags, tags); }
52 void tag_at_put(int which, jbyte t) { tags()->byte_at_put(which, t); }
53 void release_tag_at_put(int which, jbyte t) { tags()->release_byte_at_put(which, t); }
55 enum FlagBit {
56 FB_has_invokedynamic = 1,
57 FB_has_pseudo_string = 2
58 };
60 int flags() const { return _flags; }
61 void set_flags(int f) { _flags = f; }
62 bool flag_at(FlagBit fb) const { return (_flags & (1 << (int)fb)) != 0; }
63 void set_flag_at(FlagBit fb);
64 // no clear_flag_at function; they only increase
66 private:
67 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(constantPoolOopDesc)); }
68 oop* tags_addr() { return (oop*)&_tags; }
69 oop* cache_addr() { return (oop*)&_cache; }
71 oop* obj_at_addr(int which) const {
72 assert(is_within_bounds(which), "index out of bounds");
73 return (oop*) &base()[which];
74 }
76 jint* int_at_addr(int which) const {
77 assert(is_within_bounds(which), "index out of bounds");
78 return (jint*) &base()[which];
79 }
81 jlong* long_at_addr(int which) const {
82 assert(is_within_bounds(which), "index out of bounds");
83 return (jlong*) &base()[which];
84 }
86 jfloat* float_at_addr(int which) const {
87 assert(is_within_bounds(which), "index out of bounds");
88 return (jfloat*) &base()[which];
89 }
91 jdouble* double_at_addr(int which) const {
92 assert(is_within_bounds(which), "index out of bounds");
93 return (jdouble*) &base()[which];
94 }
96 public:
97 typeArrayOop tags() const { return _tags; }
99 bool has_pseudo_string() const { return flag_at(FB_has_pseudo_string); }
100 bool has_invokedynamic() const { return flag_at(FB_has_invokedynamic); }
101 void set_pseudo_string() { set_flag_at(FB_has_pseudo_string); }
102 void set_invokedynamic() { set_flag_at(FB_has_invokedynamic); }
104 // Klass holding pool
105 klassOop pool_holder() const { return _pool_holder; }
106 void set_pool_holder(klassOop k) { oop_store_without_check((oop*)&_pool_holder, (oop) k); }
107 oop* pool_holder_addr() { return (oop*)&_pool_holder; }
109 // Interpreter runtime support
110 constantPoolCacheOop cache() const { return _cache; }
111 void set_cache(constantPoolCacheOop cache){ oop_store((oop*)&_cache, cache); }
113 // Assembly code support
114 static int tags_offset_in_bytes() { return offset_of(constantPoolOopDesc, _tags); }
115 static int cache_offset_in_bytes() { return offset_of(constantPoolOopDesc, _cache); }
116 static int pool_holder_offset_in_bytes() { return offset_of(constantPoolOopDesc, _pool_holder); }
118 // Storing constants
120 void klass_at_put(int which, klassOop k) {
121 oop_store_without_check((volatile oop *)obj_at_addr(which), oop(k));
122 // The interpreter assumes when the tag is stored, the klass is resolved
123 // and the klassOop is a klass rather than a symbolOop, so we need
124 // hardware store ordering here.
125 release_tag_at_put(which, JVM_CONSTANT_Class);
126 if (UseConcMarkSweepGC) {
127 // In case the earlier card-mark was consumed by a concurrent
128 // marking thread before the tag was updated, redirty the card.
129 oop_store_without_check((volatile oop *)obj_at_addr(which), oop(k));
130 }
131 }
133 // For temporary use while constructing constant pool
134 void klass_index_at_put(int which, int name_index) {
135 tag_at_put(which, JVM_CONSTANT_ClassIndex);
136 *int_at_addr(which) = name_index;
137 }
139 // Temporary until actual use
140 void unresolved_klass_at_put(int which, symbolOop s) {
141 // Overwrite the old index with a GC friendly value so
142 // that if GC looks during the transition it won't try
143 // to treat a small integer as oop.
144 *obj_at_addr(which) = NULL;
145 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass);
146 oop_store_without_check(obj_at_addr(which), oop(s));
147 }
149 // Temporary until actual use
150 void unresolved_string_at_put(int which, symbolOop s) {
151 *obj_at_addr(which) = NULL;
152 release_tag_at_put(which, JVM_CONSTANT_UnresolvedString);
153 oop_store_without_check(obj_at_addr(which), oop(s));
154 }
156 void int_at_put(int which, jint i) {
157 tag_at_put(which, JVM_CONSTANT_Integer);
158 *int_at_addr(which) = i;
159 }
161 void long_at_put(int which, jlong l) {
162 tag_at_put(which, JVM_CONSTANT_Long);
163 // *long_at_addr(which) = l;
164 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l));
165 }
167 void float_at_put(int which, jfloat f) {
168 tag_at_put(which, JVM_CONSTANT_Float);
169 *float_at_addr(which) = f;
170 }
172 void double_at_put(int which, jdouble d) {
173 tag_at_put(which, JVM_CONSTANT_Double);
174 // *double_at_addr(which) = d;
175 // u8 temp = *(u8*) &d;
176 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d));
177 }
179 void symbol_at_put(int which, symbolOop s) {
180 tag_at_put(which, JVM_CONSTANT_Utf8);
181 oop_store_without_check(obj_at_addr(which), oop(s));
182 }
184 void string_at_put(int which, oop str) {
185 oop_store((volatile oop*)obj_at_addr(which), str);
186 release_tag_at_put(which, JVM_CONSTANT_String);
187 if (UseConcMarkSweepGC) {
188 // In case the earlier card-mark was consumed by a concurrent
189 // marking thread before the tag was updated, redirty the card.
190 oop_store_without_check((volatile oop *)obj_at_addr(which), str);
191 }
192 }
194 // For temporary use while constructing constant pool
195 void string_index_at_put(int which, int string_index) {
196 tag_at_put(which, JVM_CONSTANT_StringIndex);
197 *int_at_addr(which) = string_index;
198 }
200 void field_at_put(int which, int class_index, int name_and_type_index) {
201 tag_at_put(which, JVM_CONSTANT_Fieldref);
202 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
203 }
205 void method_at_put(int which, int class_index, int name_and_type_index) {
206 tag_at_put(which, JVM_CONSTANT_Methodref);
207 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
208 }
210 void interface_method_at_put(int which, int class_index, int name_and_type_index) {
211 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref);
212 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice
213 }
215 void name_and_type_at_put(int which, int name_index, int signature_index) {
216 tag_at_put(which, JVM_CONSTANT_NameAndType);
217 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice
218 }
220 // Tag query
222 constantTag tag_at(int which) const { return (constantTag)tags()->byte_at_acquire(which); }
224 // Whether the entry is a pointer that must be GC'd.
225 bool is_pointer_entry(int which) {
226 constantTag tag = tag_at(which);
227 return tag.is_klass() ||
228 tag.is_unresolved_klass() ||
229 tag.is_symbol() ||
230 tag.is_unresolved_string() ||
231 tag.is_string();
232 }
234 // Fetching constants
236 klassOop klass_at(int which, TRAPS) {
237 constantPoolHandle h_this(THREAD, this);
238 return klass_at_impl(h_this, which, CHECK_NULL);
239 }
241 symbolOop klass_name_at(int which); // Returns the name, w/o resolving.
243 klassOop resolved_klass_at(int which) { // Used by Compiler
244 guarantee(tag_at(which).is_klass(), "Corrupted constant pool");
245 // Must do an acquire here in case another thread resolved the klass
246 // behind our back, lest we later load stale values thru the oop.
247 return klassOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
248 }
250 // This method should only be used with a cpool lock or during parsing or gc
251 symbolOop unresolved_klass_at(int which) { // Temporary until actual use
252 symbolOop s = symbolOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
253 // check that the klass is still unresolved.
254 assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool");
255 return s;
256 }
258 // RedefineClasses() API support:
259 symbolOop klass_at_noresolve(int which) { return klass_name_at(which); }
261 jint int_at(int which) {
262 assert(tag_at(which).is_int(), "Corrupted constant pool");
263 return *int_at_addr(which);
264 }
266 jlong long_at(int which) {
267 assert(tag_at(which).is_long(), "Corrupted constant pool");
268 // return *long_at_addr(which);
269 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
270 return *((jlong*)&tmp);
271 }
273 jfloat float_at(int which) {
274 assert(tag_at(which).is_float(), "Corrupted constant pool");
275 return *float_at_addr(which);
276 }
278 jdouble double_at(int which) {
279 assert(tag_at(which).is_double(), "Corrupted constant pool");
280 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
281 return *((jdouble*)&tmp);
282 }
284 symbolOop symbol_at(int which) {
285 assert(tag_at(which).is_utf8(), "Corrupted constant pool");
286 return symbolOop(*obj_at_addr(which));
287 }
289 oop string_at(int which, TRAPS) {
290 constantPoolHandle h_this(THREAD, this);
291 return string_at_impl(h_this, which, CHECK_NULL);
292 }
294 // A "pseudo-string" is an non-string oop that has found is way into
295 // a String entry.
296 // Under AnonymousClasses this can happen if the user patches a live
297 // object into a CONSTANT_String entry of an anonymous class.
298 // Method oops internally created for method handles may also
299 // use pseudo-strings to link themselves to related metaobjects.
301 bool is_pseudo_string_at(int which);
303 oop pseudo_string_at(int which) {
304 assert(tag_at(which).is_string(), "Corrupted constant pool");
305 return *obj_at_addr(which);
306 }
308 void pseudo_string_at_put(int which, oop x) {
309 assert(AnonymousClasses, "");
310 set_pseudo_string(); // mark header
311 assert(tag_at(which).is_string() || tag_at(which).is_unresolved_string(), "Corrupted constant pool");
312 string_at_put(which, x); // this works just fine
313 }
315 // only called when we are sure a string entry is already resolved (via an
316 // earlier string_at call.
317 oop resolved_string_at(int which) {
318 assert(tag_at(which).is_string(), "Corrupted constant pool");
319 // Must do an acquire here in case another thread resolved the klass
320 // behind our back, lest we later load stale values thru the oop.
321 return (oop)OrderAccess::load_ptr_acquire(obj_at_addr(which));
322 }
324 // This method should only be used with a cpool lock or during parsing or gc
325 symbolOop unresolved_string_at(int which) { // Temporary until actual use
326 symbolOop s = symbolOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
327 // check that the string is still unresolved.
328 assert(tag_at(which).is_unresolved_string(), "Corrupted constant pool");
329 return s;
330 }
332 // Returns an UTF8 for a CONSTANT_String entry at a given index.
333 // UTF8 char* representation was chosen to avoid conversion of
334 // java_lang_Strings at resolved entries into symbolOops
335 // or vice versa.
336 // Caller is responsible for checking for pseudo-strings.
337 char* string_at_noresolve(int which);
339 jint name_and_type_at(int which) {
340 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
341 return *int_at_addr(which);
342 }
344 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve,
345 // name_and_type_ref_index_at) all expect constant pool indices
346 // from the bytecodes to be passed in, which are actually potentially byte-swapped
347 // or rewritten constant pool cache indices. They all call map_instruction_operand_to_index.
348 int map_instruction_operand_to_index(int operand);
350 // There are also "uncached" versions which do not map the operand index; see below.
352 // Lookup for entries consisting of (klass_index, name_and_type index)
353 klassOop klass_ref_at(int which, TRAPS);
354 symbolOop klass_ref_at_noresolve(int which);
355 symbolOop name_ref_at(int which) { return impl_name_ref_at(which, false); }
356 symbolOop signature_ref_at(int which) { return impl_signature_ref_at(which, false); }
358 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); }
359 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); }
361 // Lookup for entries consisting of (name_index, signature_index)
362 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt)
363 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt)
364 symbolOop nt_name_ref_at(int which_nt) { return symbol_at(name_ref_index_at(which_nt)); }
365 symbolOop nt_signature_ref_at(int which_nt) { return symbol_at(signature_ref_index_at(which_nt)); }
367 BasicType basic_type_for_signature_at(int which);
369 // Resolve string constants (to prevent allocation during compilation)
370 void resolve_string_constants(TRAPS) {
371 constantPoolHandle h_this(THREAD, this);
372 resolve_string_constants_impl(h_this, CHECK);
373 }
375 // Klass name matches name at offset
376 bool klass_name_at_matches(instanceKlassHandle k, int which);
378 // Sizing
379 int length() const { return _length; }
380 void set_length(int length) { _length = length; }
382 // Tells whether index is within bounds.
383 bool is_within_bounds(int index) const {
384 return 0 <= index && index < length();
385 }
387 static int header_size() { return sizeof(constantPoolOopDesc)/HeapWordSize; }
388 static int object_size(int length) { return align_object_size(header_size() + length); }
389 int object_size() { return object_size(length()); }
391 bool is_conc_safe() { return _is_conc_safe; }
392 void set_is_conc_safe(bool v) { _is_conc_safe = v; }
394 friend class constantPoolKlass;
395 friend class ClassFileParser;
396 friend class SystemDictionary;
398 // Used by compiler to prevent classloading.
399 static klassOop klass_at_if_loaded (constantPoolHandle this_oop, int which);
400 static klassOop klass_ref_at_if_loaded (constantPoolHandle this_oop, int which);
401 // Same as above - but does LinkResolving.
402 static klassOop klass_ref_at_if_loaded_check(constantPoolHandle this_oop, int which, TRAPS);
404 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
405 // future by other Java code. These take constant pool indices rather than possibly-byte-swapped
406 // constant pool cache indices as do the peer methods above.
407 symbolOop uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); }
408 symbolOop uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); }
409 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); }
410 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); }
412 // Sharing
413 int pre_resolve_shared_klasses(TRAPS);
414 void shared_symbols_iterate(OopClosure* closure0);
415 void shared_tags_iterate(OopClosure* closure0);
416 void shared_strings_iterate(OopClosure* closure0);
418 // Debugging
419 const char* printable_name_at(int which) PRODUCT_RETURN0;
421 private:
423 symbolOop impl_name_ref_at(int which, bool uncached);
424 symbolOop impl_signature_ref_at(int which, bool uncached);
425 int impl_klass_ref_index_at(int which, bool uncached);
426 int impl_name_and_type_ref_index_at(int which, bool uncached);
428 // Takes either a constant pool cache index in possibly byte-swapped
429 // byte order (which comes from the bytecodes after rewriting) or,
430 // if "uncached" is true, a vanilla constant pool index
431 jint field_or_method_at(int which, bool uncached) {
432 int i = which;
433 if (!uncached && cache() != NULL) {
434 // change byte-ordering and go via cache
435 i = map_instruction_operand_to_index(which);
436 }
437 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
438 return *int_at_addr(i);
439 }
441 // Used while constructing constant pool (only by ClassFileParser)
442 jint klass_index_at(int which) {
443 assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
444 return *int_at_addr(which);
445 }
447 jint string_index_at(int which) {
448 assert(tag_at(which).is_string_index(), "Corrupted constant pool");
449 return *int_at_addr(which);
450 }
452 // Performs the LinkResolver checks
453 static void verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle klass, TRAPS);
455 // Implementation of methods that needs an exposed 'this' pointer, in order to
456 // handle GC while executing the method
457 static klassOop klass_at_impl(constantPoolHandle this_oop, int which, TRAPS);
458 static oop string_at_impl(constantPoolHandle this_oop, int which, TRAPS);
460 // Resolve string constants (to prevent allocation during compilation)
461 static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS);
463 public:
464 // Merging constantPoolOop support:
465 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS);
466 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i,
467 TRAPS);
468 void copy_entry_to(int from_i, constantPoolHandle to_cp, int to_i, TRAPS);
469 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS);
470 int orig_length() const { return _orig_length; }
471 void set_orig_length(int orig_length) { _orig_length = orig_length; }
474 // JVMTI accesss - GetConstantPool, RetransformClasses, ...
475 friend class JvmtiConstantPoolReconstituter;
477 private:
478 jint cpool_entry_size(jint idx);
479 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
481 // Copy cpool bytes into byte array.
482 // Returns:
483 // int > 0, count of the raw cpool bytes that have been copied
484 // 0, OutOfMemory error
485 // -1, Internal error
486 int copy_cpool_bytes(int cpool_size,
487 SymbolHashMap* tbl,
488 unsigned char *bytes);
489 };
491 class SymbolHashMapEntry : public CHeapObj {
492 private:
493 unsigned int _hash; // 32-bit hash for item
494 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
495 symbolOop _symbol; // 1-st part of the mapping: symbol => value
496 u2 _value; // 2-nd part of the mapping: symbol => value
498 public:
499 unsigned int hash() const { return _hash; }
500 void set_hash(unsigned int hash) { _hash = hash; }
502 SymbolHashMapEntry* next() const { return _next; }
503 void set_next(SymbolHashMapEntry* next) { _next = next; }
505 symbolOop symbol() const { return _symbol; }
506 void set_symbol(symbolOop sym) { _symbol = sym; }
508 u2 value() const { return _value; }
509 void set_value(u2 value) { _value = value; }
511 SymbolHashMapEntry(unsigned int hash, symbolOop symbol, u2 value)
512 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
514 }; // End SymbolHashMapEntry class
517 class SymbolHashMapBucket : public CHeapObj {
519 private:
520 SymbolHashMapEntry* _entry;
522 public:
523 SymbolHashMapEntry* entry() const { return _entry; }
524 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
525 void clear() { _entry = NULL; }
527 }; // End SymbolHashMapBucket class
530 class SymbolHashMap: public CHeapObj {
532 private:
533 // Default number of entries in the table
534 enum SymbolHashMap_Constants {
535 _Def_HashMap_Size = 256
536 };
538 int _table_size;
539 SymbolHashMapBucket* _buckets;
541 void initialize_table(int table_size) {
542 _table_size = table_size;
543 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size);
544 for (int index = 0; index < table_size; index++) {
545 _buckets[index].clear();
546 }
547 }
549 public:
551 int table_size() const { return _table_size; }
553 SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
554 SymbolHashMap(int table_size) { initialize_table(table_size); }
556 // hash P(31) from Kernighan & Ritchie
557 static unsigned int compute_hash(const char* str, int len) {
558 unsigned int hash = 0;
559 while (len-- > 0) {
560 hash = 31*hash + (unsigned) *str;
561 str++;
562 }
563 return hash;
564 }
566 SymbolHashMapEntry* bucket(int i) {
567 return _buckets[i].entry();
568 }
570 void add_entry(symbolOop sym, u2 value);
571 SymbolHashMapEntry* find_entry(symbolOop sym);
573 u2 symbol_to_value(symbolOop sym) {
574 SymbolHashMapEntry *entry = find_entry(sym);
575 return (entry == NULL) ? 0 : entry->value();
576 }
578 ~SymbolHashMap() {
579 SymbolHashMapEntry* next;
580 for (int i = 0; i < _table_size; i++) {
581 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
582 next = cur->next();
583 delete(cur);
584 }
585 }
586 delete _buckets;
587 }
588 }; // End SymbolHashMap class