Fri, 23 Mar 2012 11:16:05 -0400
7150058: Allocate symbols from null boot loader to an arena for NMT
Summary: Move symbol allocation to an arena so NMT doesn't have to track them at startup.
Reviewed-by: never, kamg, zgu
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
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 */
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/symbolTable.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "gc_interface/collectedHeap.inline.hpp"
30 #include "memory/allocation.inline.hpp"
31 #include "memory/filemap.hpp"
32 #include "memory/gcLocker.inline.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "oops/oop.inline2.hpp"
35 #include "runtime/mutexLocker.hpp"
36 #include "utilities/hashtable.inline.hpp"
38 // --------------------------------------------------------------------------
40 SymbolTable* SymbolTable::_the_table = NULL;
41 // Static arena for symbols that are not deallocated
42 Arena* SymbolTable::_arena = NULL;
44 Symbol* SymbolTable::allocate_symbol(const u1* name, int len, bool c_heap, TRAPS) {
45 // Don't allow symbols to be created which cannot fit in a Symbol*.
46 if (len > Symbol::max_length()) {
47 THROW_MSG_0(vmSymbols::java_lang_InternalError(),
48 "name is too long to represent");
49 }
50 Symbol* sym;
51 // Allocate symbols in the C heap when dumping shared spaces in case there
52 // are temporary symbols we can remove.
53 if (c_heap || DumpSharedSpaces) {
54 // refcount starts as 1
55 sym = new (len, THREAD) Symbol(name, len, 1);
56 } else {
57 sym = new (len, arena(), THREAD) Symbol(name, len, -1);
58 }
59 assert(sym != NULL, "new should call vm_exit_out_of_memory if C_HEAP is exhausted");
60 return sym;
61 }
63 void SymbolTable::initialize_symbols(int arena_alloc_size) {
64 // Initialize the arena for global symbols, size passed in depends on CDS.
65 if (arena_alloc_size == 0) {
66 _arena = new Arena();
67 } else {
68 _arena = new Arena(arena_alloc_size);
69 }
70 }
72 // Call function for all symbols in the symbol table.
73 void SymbolTable::symbols_do(SymbolClosure *cl) {
74 const int n = the_table()->table_size();
75 for (int i = 0; i < n; i++) {
76 for (HashtableEntry<Symbol*>* p = the_table()->bucket(i);
77 p != NULL;
78 p = p->next()) {
79 cl->do_symbol(p->literal_addr());
80 }
81 }
82 }
84 int SymbolTable::symbols_removed = 0;
85 int SymbolTable::symbols_counted = 0;
87 // Remove unreferenced symbols from the symbol table
88 // This is done late during GC.
89 void SymbolTable::unlink() {
90 int removed = 0;
91 int total = 0;
92 size_t memory_total = 0;
93 for (int i = 0; i < the_table()->table_size(); ++i) {
94 for (HashtableEntry<Symbol*>** p = the_table()->bucket_addr(i); *p != NULL; ) {
95 HashtableEntry<Symbol*>* entry = *p;
96 if (entry->is_shared()) {
97 break;
98 }
99 Symbol* s = entry->literal();
100 memory_total += s->object_size();
101 total++;
102 assert(s != NULL, "just checking");
103 // If reference count is zero, remove.
104 if (s->refcount() == 0) {
105 delete s;
106 removed++;
107 *p = entry->next();
108 the_table()->free_entry(entry);
109 } else {
110 p = entry->next_addr();
111 }
112 }
113 }
114 symbols_removed += removed;
115 symbols_counted += total;
116 // Exclude printing for normal PrintGCDetails because people parse
117 // this output.
118 if (PrintGCDetails && Verbose && WizardMode) {
119 gclog_or_tty->print(" [Symbols=%d size=" SIZE_FORMAT "K] ", total,
120 (memory_total*HeapWordSize)/1024);
121 }
122 }
125 // Lookup a symbol in a bucket.
127 Symbol* SymbolTable::lookup(int index, const char* name,
128 int len, unsigned int hash) {
129 for (HashtableEntry<Symbol*>* e = bucket(index); e != NULL; e = e->next()) {
130 if (e->hash() == hash) {
131 Symbol* sym = e->literal();
132 if (sym->equals(name, len)) {
133 // something is referencing this symbol now.
134 sym->increment_refcount();
135 return sym;
136 }
137 }
138 }
139 return NULL;
140 }
143 // We take care not to be blocking while holding the
144 // SymbolTable_lock. Otherwise, the system might deadlock, since the
145 // symboltable is used during compilation (VM_thread) The lock free
146 // synchronization is simplified by the fact that we do not delete
147 // entries in the symbol table during normal execution (only during
148 // safepoints).
150 Symbol* SymbolTable::lookup(const char* name, int len, TRAPS) {
151 unsigned int hashValue = hash_symbol(name, len);
152 int index = the_table()->hash_to_index(hashValue);
154 Symbol* s = the_table()->lookup(index, name, len, hashValue);
156 // Found
157 if (s != NULL) return s;
159 // Otherwise, add to symbol to table
160 return the_table()->basic_add(index, (u1*)name, len, hashValue, true, CHECK_NULL);
161 }
163 Symbol* SymbolTable::lookup(const Symbol* sym, int begin, int end, TRAPS) {
164 char* buffer;
165 int index, len;
166 unsigned int hashValue;
167 char* name;
168 {
169 debug_only(No_Safepoint_Verifier nsv;)
171 name = (char*)sym->base() + begin;
172 len = end - begin;
173 hashValue = hash_symbol(name, len);
174 index = the_table()->hash_to_index(hashValue);
175 Symbol* s = the_table()->lookup(index, name, len, hashValue);
177 // Found
178 if (s != NULL) return s;
179 }
181 // Otherwise, add to symbol to table. Copy to a C string first.
182 char stack_buf[128];
183 ResourceMark rm(THREAD);
184 if (len <= 128) {
185 buffer = stack_buf;
186 } else {
187 buffer = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
188 }
189 for (int i=0; i<len; i++) {
190 buffer[i] = name[i];
191 }
192 // Make sure there is no safepoint in the code above since name can't move.
193 // We can't include the code in No_Safepoint_Verifier because of the
194 // ResourceMark.
196 return the_table()->basic_add(index, (u1*)buffer, len, hashValue, true, CHECK_NULL);
197 }
199 Symbol* SymbolTable::lookup_only(const char* name, int len,
200 unsigned int& hash) {
201 hash = hash_symbol(name, len);
202 int index = the_table()->hash_to_index(hash);
204 Symbol* s = the_table()->lookup(index, name, len, hash);
205 return s;
206 }
208 // Look up the address of the literal in the SymbolTable for this Symbol*
209 // Do not create any new symbols
210 // Do not increment the reference count to keep this alive
211 Symbol** SymbolTable::lookup_symbol_addr(Symbol* sym){
212 unsigned int hash = hash_symbol((char*)sym->bytes(), sym->utf8_length());
213 int index = the_table()->hash_to_index(hash);
215 for (HashtableEntry<Symbol*>* e = the_table()->bucket(index); e != NULL; e = e->next()) {
216 if (e->hash() == hash) {
217 Symbol* literal_sym = e->literal();
218 if (sym == literal_sym) {
219 return e->literal_addr();
220 }
221 }
222 }
223 return NULL;
224 }
226 // Suggestion: Push unicode-based lookup all the way into the hashing
227 // and probing logic, so there is no need for convert_to_utf8 until
228 // an actual new Symbol* is created.
229 Symbol* SymbolTable::lookup_unicode(const jchar* name, int utf16_length, TRAPS) {
230 int utf8_length = UNICODE::utf8_length((jchar*) name, utf16_length);
231 char stack_buf[128];
232 if (utf8_length < (int) sizeof(stack_buf)) {
233 char* chars = stack_buf;
234 UNICODE::convert_to_utf8(name, utf16_length, chars);
235 return lookup(chars, utf8_length, THREAD);
236 } else {
237 ResourceMark rm(THREAD);
238 char* chars = NEW_RESOURCE_ARRAY(char, utf8_length + 1);;
239 UNICODE::convert_to_utf8(name, utf16_length, chars);
240 return lookup(chars, utf8_length, THREAD);
241 }
242 }
244 Symbol* SymbolTable::lookup_only_unicode(const jchar* name, int utf16_length,
245 unsigned int& hash) {
246 int utf8_length = UNICODE::utf8_length((jchar*) name, utf16_length);
247 char stack_buf[128];
248 if (utf8_length < (int) sizeof(stack_buf)) {
249 char* chars = stack_buf;
250 UNICODE::convert_to_utf8(name, utf16_length, chars);
251 return lookup_only(chars, utf8_length, hash);
252 } else {
253 ResourceMark rm;
254 char* chars = NEW_RESOURCE_ARRAY(char, utf8_length + 1);;
255 UNICODE::convert_to_utf8(name, utf16_length, chars);
256 return lookup_only(chars, utf8_length, hash);
257 }
258 }
260 void SymbolTable::add(Handle class_loader, constantPoolHandle cp,
261 int names_count,
262 const char** names, int* lengths, int* cp_indices,
263 unsigned int* hashValues, TRAPS) {
264 SymbolTable* table = the_table();
265 bool added = table->basic_add(class_loader, cp, names_count, names, lengths,
266 cp_indices, hashValues, CHECK);
267 if (!added) {
268 // do it the hard way
269 for (int i=0; i<names_count; i++) {
270 int index = table->hash_to_index(hashValues[i]);
271 bool c_heap = class_loader() != NULL;
272 Symbol* sym = table->basic_add(index, (u1*)names[i], lengths[i], hashValues[i], c_heap, CHECK);
273 cp->symbol_at_put(cp_indices[i], sym);
274 }
275 }
276 }
278 Symbol* SymbolTable::new_permanent_symbol(const char* name, TRAPS) {
279 unsigned int hash;
280 Symbol* result = SymbolTable::lookup_only((char*)name, (int)strlen(name), hash);
281 if (result != NULL) {
282 return result;
283 }
284 SymbolTable* table = the_table();
285 int index = table->hash_to_index(hash);
286 return table->basic_add(index, (u1*)name, (int)strlen(name), hash, false, THREAD);
287 }
289 Symbol* SymbolTable::basic_add(int index, u1 *name, int len,
290 unsigned int hashValue, bool c_heap, TRAPS) {
291 assert(!Universe::heap()->is_in_reserved(name) || GC_locker::is_active(),
292 "proposed name of symbol must be stable");
294 // Grab SymbolTable_lock first.
295 MutexLocker ml(SymbolTable_lock, THREAD);
297 // Since look-up was done lock-free, we need to check if another
298 // thread beat us in the race to insert the symbol.
299 Symbol* test = lookup(index, (char*)name, len, hashValue);
300 if (test != NULL) {
301 // A race occurred and another thread introduced the symbol.
302 assert(test->refcount() != 0, "lookup should have incremented the count");
303 return test;
304 }
306 // Create a new symbol.
307 Symbol* sym = allocate_symbol(name, len, c_heap, CHECK_NULL);
308 assert(sym->equals((char*)name, len), "symbol must be properly initialized");
310 HashtableEntry<Symbol*>* entry = new_entry(hashValue, sym);
311 add_entry(index, entry);
312 return sym;
313 }
315 // This version of basic_add adds symbols in batch from the constant pool
316 // parsing.
317 bool SymbolTable::basic_add(Handle class_loader, constantPoolHandle cp,
318 int names_count,
319 const char** names, int* lengths,
320 int* cp_indices, unsigned int* hashValues,
321 TRAPS) {
323 // Check symbol names are not too long. If any are too long, don't add any.
324 for (int i = 0; i< names_count; i++) {
325 if (lengths[i] > Symbol::max_length()) {
326 THROW_MSG_0(vmSymbols::java_lang_InternalError(),
327 "name is too long to represent");
328 }
329 }
331 // Hold SymbolTable_lock through the symbol creation
332 MutexLocker ml(SymbolTable_lock, THREAD);
334 for (int i=0; i<names_count; i++) {
335 // Since look-up was done lock-free, we need to check if another
336 // thread beat us in the race to insert the symbol.
337 int index = hash_to_index(hashValues[i]);
338 Symbol* test = lookup(index, names[i], lengths[i], hashValues[i]);
339 if (test != NULL) {
340 // A race occurred and another thread introduced the symbol, this one
341 // will be dropped and collected. Use test instead.
342 cp->symbol_at_put(cp_indices[i], test);
343 assert(test->refcount() != 0, "lookup should have incremented the count");
344 } else {
345 // Create a new symbol. The null class loader is never unloaded so these
346 // are allocated specially in a permanent arena.
347 bool c_heap = class_loader() != NULL;
348 Symbol* sym = allocate_symbol((const u1*)names[i], lengths[i], c_heap, CHECK_(false));
349 assert(sym->equals(names[i], lengths[i]), "symbol must be properly initialized"); // why wouldn't it be???
350 HashtableEntry<Symbol*>* entry = new_entry(hashValues[i], sym);
351 add_entry(index, entry);
352 cp->symbol_at_put(cp_indices[i], sym);
353 }
354 }
355 return true;
356 }
359 void SymbolTable::verify() {
360 for (int i = 0; i < the_table()->table_size(); ++i) {
361 HashtableEntry<Symbol*>* p = the_table()->bucket(i);
362 for ( ; p != NULL; p = p->next()) {
363 Symbol* s = (Symbol*)(p->literal());
364 guarantee(s != NULL, "symbol is NULL");
365 unsigned int h = hash_symbol((char*)s->bytes(), s->utf8_length());
366 guarantee(p->hash() == h, "broken hash in symbol table entry");
367 guarantee(the_table()->hash_to_index(h) == i,
368 "wrong index in symbol table");
369 }
370 }
371 }
374 //---------------------------------------------------------------------------
375 // Non-product code
377 #ifndef PRODUCT
379 void SymbolTable::print_histogram() {
380 MutexLocker ml(SymbolTable_lock);
381 const int results_length = 100;
382 int results[results_length];
383 int i,j;
385 // initialize results to zero
386 for (j = 0; j < results_length; j++) {
387 results[j] = 0;
388 }
390 int total = 0;
391 int max_symbols = 0;
392 int out_of_range = 0;
393 int memory_total = 0;
394 int count = 0;
395 for (i = 0; i < the_table()->table_size(); i++) {
396 HashtableEntry<Symbol*>* p = the_table()->bucket(i);
397 for ( ; p != NULL; p = p->next()) {
398 memory_total += p->literal()->object_size();
399 count++;
400 int counter = p->literal()->utf8_length();
401 total += counter;
402 if (counter < results_length) {
403 results[counter]++;
404 } else {
405 out_of_range++;
406 }
407 max_symbols = MAX2(max_symbols, counter);
408 }
409 }
410 tty->print_cr("Symbol Table:");
411 tty->print_cr("Total number of symbols %5d", count);
412 tty->print_cr("Total size in memory %5dK",
413 (memory_total*HeapWordSize)/1024);
414 tty->print_cr("Total counted %5d", symbols_counted);
415 tty->print_cr("Total removed %5d", symbols_removed);
416 if (symbols_counted > 0) {
417 tty->print_cr("Percent removed %3.2f",
418 ((float)symbols_removed/(float)symbols_counted)* 100);
419 }
420 tty->print_cr("Reference counts %5d", Symbol::_total_count);
421 tty->print_cr("Symbol arena size %5d used %5d",
422 arena()->size_in_bytes(), arena()->used());
423 tty->print_cr("Histogram of symbol length:");
424 tty->print_cr("%8s %5d", "Total ", total);
425 tty->print_cr("%8s %5d", "Maximum", max_symbols);
426 tty->print_cr("%8s %3.2f", "Average",
427 ((float) total / (float) the_table()->table_size()));
428 tty->print_cr("%s", "Histogram:");
429 tty->print_cr(" %s %29s", "Length", "Number chains that length");
430 for (i = 0; i < results_length; i++) {
431 if (results[i] > 0) {
432 tty->print_cr("%6d %10d", i, results[i]);
433 }
434 }
435 if (Verbose) {
436 int line_length = 70;
437 tty->print_cr("%s %30s", " Length", "Number chains that length");
438 for (i = 0; i < results_length; i++) {
439 if (results[i] > 0) {
440 tty->print("%4d", i);
441 for (j = 0; (j < results[i]) && (j < line_length); j++) {
442 tty->print("%1s", "*");
443 }
444 if (j == line_length) {
445 tty->print("%1s", "+");
446 }
447 tty->cr();
448 }
449 }
450 }
451 tty->print_cr(" %s %d: %d\n", "Number chains longer than",
452 results_length, out_of_range);
453 }
455 void SymbolTable::print() {
456 for (int i = 0; i < the_table()->table_size(); ++i) {
457 HashtableEntry<Symbol*>** p = the_table()->bucket_addr(i);
458 HashtableEntry<Symbol*>* entry = the_table()->bucket(i);
459 if (entry != NULL) {
460 while (entry != NULL) {
461 tty->print(PTR_FORMAT " ", entry->literal());
462 entry->literal()->print();
463 tty->print(" %d", entry->literal()->refcount());
464 p = entry->next_addr();
465 entry = (HashtableEntry<Symbol*>*)HashtableEntry<Symbol*>::make_ptr(*p);
466 }
467 tty->cr();
468 }
469 }
470 }
472 #endif // PRODUCT
474 // --------------------------------------------------------------------------
476 #ifdef ASSERT
477 class StableMemoryChecker : public StackObj {
478 enum { _bufsize = wordSize*4 };
480 address _region;
481 jint _size;
482 u1 _save_buf[_bufsize];
484 int sample(u1* save_buf) {
485 if (_size <= _bufsize) {
486 memcpy(save_buf, _region, _size);
487 return _size;
488 } else {
489 // copy head and tail
490 memcpy(&save_buf[0], _region, _bufsize/2);
491 memcpy(&save_buf[_bufsize/2], _region + _size - _bufsize/2, _bufsize/2);
492 return (_bufsize/2)*2;
493 }
494 }
496 public:
497 StableMemoryChecker(const void* region, jint size) {
498 _region = (address) region;
499 _size = size;
500 sample(_save_buf);
501 }
503 bool verify() {
504 u1 check_buf[sizeof(_save_buf)];
505 int check_size = sample(check_buf);
506 return (0 == memcmp(_save_buf, check_buf, check_size));
507 }
509 void set_region(const void* region) { _region = (address) region; }
510 };
511 #endif
514 // --------------------------------------------------------------------------
515 StringTable* StringTable::_the_table = NULL;
517 oop StringTable::lookup(int index, jchar* name,
518 int len, unsigned int hash) {
519 for (HashtableEntry<oop>* l = bucket(index); l != NULL; l = l->next()) {
520 if (l->hash() == hash) {
521 if (java_lang_String::equals(l->literal(), name, len)) {
522 return l->literal();
523 }
524 }
525 }
526 return NULL;
527 }
530 oop StringTable::basic_add(int index, Handle string_or_null, jchar* name,
531 int len, unsigned int hashValue, TRAPS) {
532 debug_only(StableMemoryChecker smc(name, len * sizeof(name[0])));
533 assert(!Universe::heap()->is_in_reserved(name) || GC_locker::is_active(),
534 "proposed name of symbol must be stable");
536 Handle string;
537 // try to reuse the string if possible
538 if (!string_or_null.is_null() && (!JavaObjectsInPerm || string_or_null()->is_perm())) {
539 string = string_or_null;
540 } else {
541 string = java_lang_String::create_tenured_from_unicode(name, len, CHECK_NULL);
542 }
544 // Allocation must be done before grapping the SymbolTable_lock lock
545 MutexLocker ml(StringTable_lock, THREAD);
547 assert(java_lang_String::equals(string(), name, len),
548 "string must be properly initialized");
550 // Since look-up was done lock-free, we need to check if another
551 // thread beat us in the race to insert the symbol.
553 oop test = lookup(index, name, len, hashValue); // calls lookup(u1*, int)
554 if (test != NULL) {
555 // Entry already added
556 return test;
557 }
559 HashtableEntry<oop>* entry = new_entry(hashValue, string());
560 add_entry(index, entry);
561 return string();
562 }
565 oop StringTable::lookup(Symbol* symbol) {
566 ResourceMark rm;
567 int length;
568 jchar* chars = symbol->as_unicode(length);
569 unsigned int hashValue = java_lang_String::hash_string(chars, length);
570 int index = the_table()->hash_to_index(hashValue);
571 return the_table()->lookup(index, chars, length, hashValue);
572 }
575 oop StringTable::intern(Handle string_or_null, jchar* name,
576 int len, TRAPS) {
577 unsigned int hashValue = java_lang_String::hash_string(name, len);
578 int index = the_table()->hash_to_index(hashValue);
579 oop string = the_table()->lookup(index, name, len, hashValue);
581 // Found
582 if (string != NULL) return string;
584 // Otherwise, add to symbol to table
585 return the_table()->basic_add(index, string_or_null, name, len,
586 hashValue, CHECK_NULL);
587 }
589 oop StringTable::intern(Symbol* symbol, TRAPS) {
590 if (symbol == NULL) return NULL;
591 ResourceMark rm(THREAD);
592 int length;
593 jchar* chars = symbol->as_unicode(length);
594 Handle string;
595 oop result = intern(string, chars, length, CHECK_NULL);
596 return result;
597 }
600 oop StringTable::intern(oop string, TRAPS)
601 {
602 if (string == NULL) return NULL;
603 ResourceMark rm(THREAD);
604 int length;
605 Handle h_string (THREAD, string);
606 jchar* chars = java_lang_String::as_unicode_string(string, length);
607 oop result = intern(h_string, chars, length, CHECK_NULL);
608 return result;
609 }
612 oop StringTable::intern(const char* utf8_string, TRAPS) {
613 if (utf8_string == NULL) return NULL;
614 ResourceMark rm(THREAD);
615 int length = UTF8::unicode_length(utf8_string);
616 jchar* chars = NEW_RESOURCE_ARRAY(jchar, length);
617 UTF8::convert_to_unicode(utf8_string, chars, length);
618 Handle string;
619 oop result = intern(string, chars, length, CHECK_NULL);
620 return result;
621 }
623 void StringTable::unlink(BoolObjectClosure* is_alive) {
624 // Readers of the table are unlocked, so we should only be removing
625 // entries at a safepoint.
626 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
627 for (int i = 0; i < the_table()->table_size(); ++i) {
628 for (HashtableEntry<oop>** p = the_table()->bucket_addr(i); *p != NULL; ) {
629 HashtableEntry<oop>* entry = *p;
630 if (entry->is_shared()) {
631 break;
632 }
633 assert(entry->literal() != NULL, "just checking");
634 if (is_alive->do_object_b(entry->literal())) {
635 p = entry->next_addr();
636 } else {
637 *p = entry->next();
638 the_table()->free_entry(entry);
639 }
640 }
641 }
642 }
644 void StringTable::oops_do(OopClosure* f) {
645 for (int i = 0; i < the_table()->table_size(); ++i) {
646 HashtableEntry<oop>** p = the_table()->bucket_addr(i);
647 HashtableEntry<oop>* entry = the_table()->bucket(i);
648 while (entry != NULL) {
649 f->do_oop((oop*)entry->literal_addr());
651 // Did the closure remove the literal from the table?
652 if (entry->literal() == NULL) {
653 assert(!entry->is_shared(), "immutable hashtable entry?");
654 *p = entry->next();
655 the_table()->free_entry(entry);
656 } else {
657 p = entry->next_addr();
658 }
659 entry = (HashtableEntry<oop>*)HashtableEntry<oop>::make_ptr(*p);
660 }
661 }
662 }
664 void StringTable::verify() {
665 for (int i = 0; i < the_table()->table_size(); ++i) {
666 HashtableEntry<oop>* p = the_table()->bucket(i);
667 for ( ; p != NULL; p = p->next()) {
668 oop s = p->literal();
669 guarantee(s != NULL, "interned string is NULL");
670 guarantee(s->is_perm() || !JavaObjectsInPerm, "interned string not in permspace");
671 unsigned int h = java_lang_String::hash_string(s);
672 guarantee(p->hash() == h, "broken hash in string table entry");
673 guarantee(the_table()->hash_to_index(h) == i,
674 "wrong index in string table");
675 }
676 }
677 }