1 /*
2 * Copyright (c) 1997, 2014, 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.
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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
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23 */
24
25 #ifndef SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
26 #define SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
27
28 #include "oops/arrayOop.hpp"
29 #include "oops/cpCache.hpp"
30 #include "oops/objArrayOop.hpp"
31 #include "oops/symbol.hpp"
32 #include "oops/typeArrayOop.hpp"
33 #include "runtime/handles.hpp"
34 #include "utilities/constantTag.hpp"
35 #ifdef TARGET_ARCH_x86
36 # include "bytes_x86.hpp"
37 #endif
38 #ifdef TARGET_ARCH_sparc
39 # include "bytes_sparc.hpp"
40 #endif
41 #ifdef TARGET_ARCH_zero
42 # include "bytes_zero.hpp"
43 #endif
44 #ifdef TARGET_ARCH_arm
45 # include "bytes_arm.hpp"
46 #endif
47 #ifdef TARGET_ARCH_ppc
48 # include "bytes_ppc.hpp"
49 #endif
50
51 // A ConstantPool is an array containing class constants as described in the
52 // class file.
53 //
54 // Most of the constant pool entries are written during class parsing, which
55 // is safe. For klass types, the constant pool entry is
56 // modified when the entry is resolved. If a klass constant pool
57 // entry is read without a lock, only the resolved state guarantees that
58 // the entry in the constant pool is a klass object and not a Symbol*.
59
60 class SymbolHashMap;
61
62 class CPSlot VALUE_OBJ_CLASS_SPEC {
63 intptr_t _ptr;
64 public:
65 CPSlot(intptr_t ptr): _ptr(ptr) {}
66 CPSlot(Klass* ptr): _ptr((intptr_t)ptr) {}
67 CPSlot(Symbol* ptr): _ptr((intptr_t)ptr | 1) {}
68
69 intptr_t value() { return _ptr; }
70 bool is_resolved() { return (_ptr & 1) == 0; }
71 bool is_unresolved() { return (_ptr & 1) == 1; }
72
73 Symbol* get_symbol() {
74 assert(is_unresolved(), "bad call");
75 return (Symbol*)(_ptr & ~1);
76 }
77 Klass* get_klass() {
78 assert(is_resolved(), "bad call");
79 return (Klass*)_ptr;
80 }
81 };
82
83 class KlassSizeStats;
84
85 class ConstantPool : public Metadata {
86 friend class VMStructs;
87 friend class BytecodeInterpreter; // Directly extracts a klass in the pool for fast instanceof/checkcast
88 friend class Universe; // For null constructor
89 private:
90 Array<u1>* _tags; // the tag array describing the constant pool's contents
91 ConstantPoolCache* _cache; // the cache holding interpreter runtime information
92 InstanceKlass* _pool_holder; // the corresponding class
93 Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty
94
95 // Array of resolved objects from the constant pool and map from resolved
96 // object index to original constant pool index
97 jobject _resolved_references;
98 Array<u2>* _reference_map;
99
100 enum {
101 _has_preresolution = 1, // Flags
102 _on_stack = 2
103 };
104
105 int _flags; // old fashioned bit twiddling
106 int _length; // number of elements in the array
107
108 union {
109 // set for CDS to restore resolved references
110 int _resolved_reference_length;
111 // keeps version number for redefined classes (used in backtrace)
112 int _version;
113 } _saved;
114
115 void set_tags(Array<u1>* tags) { _tags = tags; }
116 void tag_at_put(int which, jbyte t) { tags()->at_put(which, t); }
117 void release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); }
118
119 u1* tag_addr_at(int which) const { return tags()->adr_at(which); }
120
121 void set_operands(Array<u2>* operands) { _operands = operands; }
122
123 int flags() const { return _flags; }
124 void set_flags(int f) { _flags = f; }
125
126 private:
127 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); }
128
129 CPSlot slot_at(int which) {
130 assert(is_within_bounds(which), "index out of bounds");
131 // Uses volatile because the klass slot changes without a lock.
132 volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which));
133 assert(adr != 0 || which == 0, "cp entry for klass should not be zero");
134 return CPSlot(adr);
135 }
136
137 void slot_at_put(int which, CPSlot s) const {
138 assert(is_within_bounds(which), "index out of bounds");
139 assert(s.value() != 0, "Caught something");
140 *(intptr_t*)&base()[which] = s.value();
141 }
142 intptr_t* obj_at_addr_raw(int which) const {
143 assert(is_within_bounds(which), "index out of bounds");
144 return (intptr_t*) &base()[which];
145 }
146
147 jint* int_at_addr(int which) const {
148 assert(is_within_bounds(which), "index out of bounds");
149 return (jint*) &base()[which];
150 }
151
152 jlong* long_at_addr(int which) const {
153 assert(is_within_bounds(which), "index out of bounds");
154 return (jlong*) &base()[which];
155 }
156
157 jfloat* float_at_addr(int which) const {
158 assert(is_within_bounds(which), "index out of bounds");
159 return (jfloat*) &base()[which];
160 }
161
162 jdouble* double_at_addr(int which) const {
163 assert(is_within_bounds(which), "index out of bounds");
164 return (jdouble*) &base()[which];
165 }
166
167 ConstantPool(Array<u1>* tags);
168 ConstantPool() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
169 public:
170 static ConstantPool* allocate(ClassLoaderData* loader_data, int length, TRAPS);
171
172 bool is_constantPool() const volatile { return true; }
173
174 Array<u1>* tags() const { return _tags; }
175 Array<u2>* operands() const { return _operands; }
176
177 bool has_preresolution() const { return (_flags & _has_preresolution) != 0; }
178 void set_has_preresolution() { _flags |= _has_preresolution; }
179
180 // Redefine classes support. If a method refering to this constant pool
181 // is on the executing stack, or as a handle in vm code, this constant pool
182 // can't be removed from the set of previous versions saved in the instance
183 // class.
184 bool on_stack() const { return (_flags &_on_stack) != 0; }
185 void set_on_stack(const bool value);
186
187 // Klass holding pool
188 InstanceKlass* pool_holder() const { return _pool_holder; }
189 void set_pool_holder(InstanceKlass* k) { _pool_holder = k; }
190 InstanceKlass** pool_holder_addr() { return &_pool_holder; }
191
192 // Interpreter runtime support
193 ConstantPoolCache* cache() const { return _cache; }
194 void set_cache(ConstantPoolCache* cache){ _cache = cache; }
195
196 // Create object cache in the constant pool
197 void initialize_resolved_references(ClassLoaderData* loader_data,
198 intStack reference_map,
199 int constant_pool_map_length,
200 TRAPS);
201
202 // resolved strings, methodHandles and callsite objects from the constant pool
203 objArrayOop resolved_references() const;
204 // mapping resolved object array indexes to cp indexes and back.
205 int object_to_cp_index(int index) { return _reference_map->at(index); }
206 int cp_to_object_index(int index);
207
208 // Invokedynamic indexes.
209 // They must look completely different from normal indexes.
210 // The main reason is that byte swapping is sometimes done on normal indexes.
211 // Finally, it is helpful for debugging to tell the two apart.
212 static bool is_invokedynamic_index(int i) { return (i < 0); }
213 static int decode_invokedynamic_index(int i) { assert(is_invokedynamic_index(i), ""); return ~i; }
214 static int encode_invokedynamic_index(int i) { assert(!is_invokedynamic_index(i), ""); return ~i; }
215
216
217 // The invokedynamic points at a CP cache entry. This entry points back
218 // at the original CP entry (CONSTANT_InvokeDynamic) and also (via f2) at an entry
219 // in the resolved_references array (which provides the appendix argument).
220 int invokedynamic_cp_cache_index(int index) const {
221 assert (is_invokedynamic_index(index), "should be a invokedynamic index");
222 int cache_index = decode_invokedynamic_index(index);
223 return cache_index;
224 }
225 ConstantPoolCacheEntry* invokedynamic_cp_cache_entry_at(int index) const {
226 // decode index that invokedynamic points to.
227 int cp_cache_index = invokedynamic_cp_cache_index(index);
228 return cache()->entry_at(cp_cache_index);
229 }
230
231 // Assembly code support
232 static int tags_offset_in_bytes() { return offset_of(ConstantPool, _tags); }
233 static int cache_offset_in_bytes() { return offset_of(ConstantPool, _cache); }
234 static int pool_holder_offset_in_bytes() { return offset_of(ConstantPool, _pool_holder); }
235 static int resolved_references_offset_in_bytes() { return offset_of(ConstantPool, _resolved_references); }
236
237 // Storing constants
238
239 void klass_at_put(int which, Klass* k) {
240 assert(k != NULL, "resolved class shouldn't be null");
241 assert(is_within_bounds(which), "index out of bounds");
242 OrderAccess::release_store_ptr((Klass* volatile *)obj_at_addr_raw(which), k);
243 // The interpreter assumes when the tag is stored, the klass is resolved
244 // and the Klass* is a klass rather than a Symbol*, so we need
245 // hardware store ordering here.
246 release_tag_at_put(which, JVM_CONSTANT_Class);
247 }
248
249 // For temporary use while constructing constant pool
250 void klass_index_at_put(int which, int name_index) {
251 tag_at_put(which, JVM_CONSTANT_ClassIndex);
252 *int_at_addr(which) = name_index;
253 }
254
255 // Temporary until actual use
256 void unresolved_klass_at_put(int which, Symbol* s) {
257 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass);
258 slot_at_put(which, s);
259 }
260
261 void method_handle_index_at_put(int which, int ref_kind, int ref_index) {
262 tag_at_put(which, JVM_CONSTANT_MethodHandle);
263 *int_at_addr(which) = ((jint) ref_index<<16) | ref_kind;
264 }
265
266 void method_type_index_at_put(int which, int ref_index) {
267 tag_at_put(which, JVM_CONSTANT_MethodType);
268 *int_at_addr(which) = ref_index;
269 }
270
271 void invoke_dynamic_at_put(int which, int bootstrap_specifier_index, int name_and_type_index) {
272 tag_at_put(which, JVM_CONSTANT_InvokeDynamic);
273 *int_at_addr(which) = ((jint) name_and_type_index<<16) | bootstrap_specifier_index;
274 }
275
276 void unresolved_string_at_put(int which, Symbol* s) {
277 release_tag_at_put(which, JVM_CONSTANT_String);
278 *symbol_at_addr(which) = s;
279 }
280
281 void int_at_put(int which, jint i) {
282 tag_at_put(which, JVM_CONSTANT_Integer);
283 *int_at_addr(which) = i;
284 }
285
286 void long_at_put(int which, jlong l) {
287 tag_at_put(which, JVM_CONSTANT_Long);
288 // *long_at_addr(which) = l;
289 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l));
290 }
291
292 void float_at_put(int which, jfloat f) {
293 tag_at_put(which, JVM_CONSTANT_Float);
294 *float_at_addr(which) = f;
295 }
296
297 void double_at_put(int which, jdouble d) {
298 tag_at_put(which, JVM_CONSTANT_Double);
299 // *double_at_addr(which) = d;
300 // u8 temp = *(u8*) &d;
301 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d));
302 }
303
304 Symbol** symbol_at_addr(int which) const {
305 assert(is_within_bounds(which), "index out of bounds");
306 return (Symbol**) &base()[which];
307 }
308
309 void symbol_at_put(int which, Symbol* s) {
310 assert(s->refcount() != 0, "should have nonzero refcount");
311 tag_at_put(which, JVM_CONSTANT_Utf8);
312 *symbol_at_addr(which) = s;
313 }
314
315 void string_at_put(int which, int obj_index, oop str) {
316 resolved_references()->obj_at_put(obj_index, str);
317 }
318
319 // For temporary use while constructing constant pool
320 void string_index_at_put(int which, int string_index) {
321 tag_at_put(which, JVM_CONSTANT_StringIndex);
322 *int_at_addr(which) = string_index;
323 }
324
325 void field_at_put(int which, int class_index, int name_and_type_index) {
326 tag_at_put(which, JVM_CONSTANT_Fieldref);
327 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
328 }
329
330 void method_at_put(int which, int class_index, int name_and_type_index) {
331 tag_at_put(which, JVM_CONSTANT_Methodref);
332 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
333 }
334
335 void interface_method_at_put(int which, int class_index, int name_and_type_index) {
336 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref);
337 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice
338 }
339
340 void name_and_type_at_put(int which, int name_index, int signature_index) {
341 tag_at_put(which, JVM_CONSTANT_NameAndType);
342 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice
343 }
344
345 // Tag query
346
347 constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); }
348
349 // Fetching constants
350
351 Klass* klass_at(int which, TRAPS) {
352 constantPoolHandle h_this(THREAD, this);
353 return klass_at_impl(h_this, which, CHECK_NULL);
354 }
355
356 Symbol* klass_name_at(int which); // Returns the name, w/o resolving.
357
358 Klass* resolved_klass_at(int which) const { // Used by Compiler
359 guarantee(tag_at(which).is_klass(), "Corrupted constant pool");
360 // Must do an acquire here in case another thread resolved the klass
361 // behind our back, lest we later load stale values thru the oop.
362 return CPSlot((Klass*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_klass();
363 }
364
365 // RedefineClasses() API support:
366 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); }
367
368 jint int_at(int which) {
369 assert(tag_at(which).is_int(), "Corrupted constant pool");
370 return *int_at_addr(which);
371 }
372
373 jlong long_at(int which) {
374 assert(tag_at(which).is_long(), "Corrupted constant pool");
375 // return *long_at_addr(which);
376 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
377 return *((jlong*)&tmp);
378 }
379
380 jfloat float_at(int which) {
381 assert(tag_at(which).is_float(), "Corrupted constant pool");
382 return *float_at_addr(which);
383 }
384
385 jdouble double_at(int which) {
386 assert(tag_at(which).is_double(), "Corrupted constant pool");
387 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
388 return *((jdouble*)&tmp);
389 }
390
391 Symbol* symbol_at(int which) {
392 assert(tag_at(which).is_utf8(), "Corrupted constant pool");
393 return *symbol_at_addr(which);
394 }
395
396 oop string_at(int which, int obj_index, TRAPS) {
397 constantPoolHandle h_this(THREAD, this);
398 return string_at_impl(h_this, which, obj_index, THREAD);
399 }
400 oop string_at(int which, TRAPS) {
401 int obj_index = cp_to_object_index(which);
402 return string_at(which, obj_index, THREAD);
403 }
404
405 // Version that can be used before string oop array is created.
406 oop uncached_string_at(int which, TRAPS);
407
408 // A "pseudo-string" is an non-string oop that has found its way into
409 // a String entry.
410 // This can happen if the user patches a live
411 // object into a CONSTANT_String entry of an anonymous class.
412 // Method oops internally created for method handles may also
413 // use pseudo-strings to link themselves to related metaobjects.
414
415 bool is_pseudo_string_at(int which) {
416 // A pseudo string is a string that doesn't have a symbol in the cpSlot
417 return unresolved_string_at(which) == NULL;
418 }
419
420 oop pseudo_string_at(int which, int obj_index) {
421 assert(tag_at(which).is_string(), "Corrupted constant pool");
422 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol");
423 oop s = resolved_references()->obj_at(obj_index);
424 return s;
425 }
426
427 oop pseudo_string_at(int which) {
428 assert(tag_at(which).is_string(), "Corrupted constant pool");
429 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol");
430 int obj_index = cp_to_object_index(which);
431 oop s = resolved_references()->obj_at(obj_index);
432 return s;
433 }
434
435 void pseudo_string_at_put(int which, int obj_index, oop x) {
436 assert(tag_at(which).is_string(), "Corrupted constant pool");
437 unresolved_string_at_put(which, NULL); // indicates patched string
438 string_at_put(which, obj_index, x); // this works just fine
439 }
440
441 // only called when we are sure a string entry is already resolved (via an
442 // earlier string_at call.
443 oop resolved_string_at(int which) {
444 assert(tag_at(which).is_string(), "Corrupted constant pool");
445 // Must do an acquire here in case another thread resolved the klass
446 // behind our back, lest we later load stale values thru the oop.
447 // we might want a volatile_obj_at in ObjArrayKlass.
448 int obj_index = cp_to_object_index(which);
449 return resolved_references()->obj_at(obj_index);
450 }
451
452 Symbol* unresolved_string_at(int which) {
453 assert(tag_at(which).is_string(), "Corrupted constant pool");
454 Symbol* s = *symbol_at_addr(which);
455 return s;
456 }
457
458 // Returns an UTF8 for a CONSTANT_String entry at a given index.
459 // UTF8 char* representation was chosen to avoid conversion of
460 // java_lang_Strings at resolved entries into Symbol*s
461 // or vice versa.
462 // Caller is responsible for checking for pseudo-strings.
463 char* string_at_noresolve(int which);
464
465 jint name_and_type_at(int which) {
466 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
467 return *int_at_addr(which);
468 }
469
470 private:
471 int method_handle_ref_kind_at(int which, bool error_ok) {
472 assert(tag_at(which).is_method_handle() ||
473 (error_ok && tag_at(which).is_method_handle_in_error()), "Corrupted constant pool");
474 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits
475 }
476 int method_handle_index_at(int which, bool error_ok) {
477 assert(tag_at(which).is_method_handle() ||
478 (error_ok && tag_at(which).is_method_handle_in_error()), "Corrupted constant pool");
479 return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits
480 }
481 int method_type_index_at(int which, bool error_ok) {
482 assert(tag_at(which).is_method_type() ||
483 (error_ok && tag_at(which).is_method_type_in_error()), "Corrupted constant pool");
484 return *int_at_addr(which);
485 }
486 public:
487 int method_handle_ref_kind_at(int which) {
488 return method_handle_ref_kind_at(which, false);
489 }
490 int method_handle_ref_kind_at_error_ok(int which) {
491 return method_handle_ref_kind_at(which, true);
492 }
493 int method_handle_index_at(int which) {
494 return method_handle_index_at(which, false);
495 }
496 int method_handle_index_at_error_ok(int which) {
497 return method_handle_index_at(which, true);
498 }
499 int method_type_index_at(int which) {
500 return method_type_index_at(which, false);
501 }
502 int method_type_index_at_error_ok(int which) {
503 return method_type_index_at(which, true);
504 }
505
506 // Derived queries:
507 Symbol* method_handle_name_ref_at(int which) {
508 int member = method_handle_index_at(which);
509 return impl_name_ref_at(member, true);
510 }
511 Symbol* method_handle_signature_ref_at(int which) {
512 int member = method_handle_index_at(which);
513 return impl_signature_ref_at(member, true);
514 }
515 int method_handle_klass_index_at(int which) {
516 int member = method_handle_index_at(which);
517 return impl_klass_ref_index_at(member, true);
518 }
519 Symbol* method_type_signature_at(int which) {
520 int sym = method_type_index_at(which);
521 return symbol_at(sym);
522 }
523
524 int invoke_dynamic_name_and_type_ref_index_at(int which) {
525 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
526 return extract_high_short_from_int(*int_at_addr(which));
527 }
528 int invoke_dynamic_bootstrap_specifier_index(int which) {
529 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool");
530 return extract_low_short_from_int(*int_at_addr(which));
531 }
532 int invoke_dynamic_operand_base(int which) {
533 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
534 return operand_offset_at(operands(), bootstrap_specifier_index);
535 }
536 // The first part of the operands array consists of an index into the second part.
537 // Extract a 32-bit index value from the first part.
538 static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) {
539 int n = (bootstrap_specifier_index * 2);
540 assert(n >= 0 && n+2 <= operands->length(), "oob");
541 // The first 32-bit index points to the beginning of the second part
542 // of the operands array. Make sure this index is in the first part.
543 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0),
544 operands->at(1)));
545 assert(second_part == 0 || n+2 <= second_part, "oob (2)");
546 int offset = build_int_from_shorts(operands->at(n+0),
547 operands->at(n+1));
548 // The offset itself must point into the second part of the array.
549 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)");
550 return offset;
551 }
552 static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) {
553 int n = bootstrap_specifier_index * 2;
554 assert(n >= 0 && n+2 <= operands->length(), "oob");
555 operands->at_put(n+0, extract_low_short_from_int(offset));
556 operands->at_put(n+1, extract_high_short_from_int(offset));
557 }
558 static int operand_array_length(Array<u2>* operands) {
559 if (operands == NULL || operands->length() == 0) return 0;
560 int second_part = operand_offset_at(operands, 0);
561 return (second_part / 2);
562 }
563
564 #ifdef ASSERT
565 // operand tuples fit together exactly, end to end
566 static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) {
567 int nextidx = bootstrap_specifier_index + 1;
568 if (nextidx == operand_array_length(operands))
569 return operands->length();
570 else
571 return operand_offset_at(operands, nextidx);
572 }
573 int invoke_dynamic_operand_limit(int which) {
574 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
575 return operand_limit_at(operands(), bootstrap_specifier_index);
576 }
577 #endif //ASSERT
578
579 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array):
580 enum {
581 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm
582 _indy_argc_offset = 1, // u2 argc
583 _indy_argv_offset = 2 // u2 argv[argc]
584 };
585
586 // These functions are used in RedefineClasses for CP merge
587
588 int operand_offset_at(int bootstrap_specifier_index) {
589 assert(0 <= bootstrap_specifier_index &&
590 bootstrap_specifier_index < operand_array_length(operands()),
591 "Corrupted CP operands");
592 return operand_offset_at(operands(), bootstrap_specifier_index);
593 }
594 int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) {
595 int offset = operand_offset_at(bootstrap_specifier_index);
596 return operands()->at(offset + _indy_bsm_offset);
597 }
598 int operand_argument_count_at(int bootstrap_specifier_index) {
599 int offset = operand_offset_at(bootstrap_specifier_index);
600 int argc = operands()->at(offset + _indy_argc_offset);
601 return argc;
602 }
603 int operand_argument_index_at(int bootstrap_specifier_index, int j) {
604 int offset = operand_offset_at(bootstrap_specifier_index);
605 return operands()->at(offset + _indy_argv_offset + j);
606 }
607 int operand_next_offset_at(int bootstrap_specifier_index) {
608 int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset
609 + operand_argument_count_at(bootstrap_specifier_index);
610 return offset;
611 }
612 // Compare a bootsrap specifier in the operands arrays
613 bool compare_operand_to(int bootstrap_specifier_index1, constantPoolHandle cp2,
614 int bootstrap_specifier_index2, TRAPS);
615 // Find a bootsrap specifier in the operands array
616 int find_matching_operand(int bootstrap_specifier_index, constantPoolHandle search_cp,
617 int operands_cur_len, TRAPS);
618 // Resize the operands array with delta_len and delta_size
619 void resize_operands(int delta_len, int delta_size, TRAPS);
620 // Extend the operands array with the length and size of the ext_cp operands
621 void extend_operands(constantPoolHandle ext_cp, TRAPS);
622 // Shrink the operands array to a smaller array with new_len length
623 void shrink_operands(int new_len, TRAPS);
624
625
626 int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
627 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
628 int op_base = invoke_dynamic_operand_base(which);
629 return operands()->at(op_base + _indy_bsm_offset);
630 }
631 int invoke_dynamic_argument_count_at(int which) {
632 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
633 int op_base = invoke_dynamic_operand_base(which);
634 int argc = operands()->at(op_base + _indy_argc_offset);
635 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc;
636 int next_offset = invoke_dynamic_operand_limit(which));
637 assert(end_offset == next_offset, "matched ending");
638 return argc;
639 }
640 int invoke_dynamic_argument_index_at(int which, int j) {
641 int op_base = invoke_dynamic_operand_base(which);
642 DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset));
643 assert((uint)j < (uint)argc, "oob");
644 return operands()->at(op_base + _indy_argv_offset + j);
645 }
646
647 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve,
648 // name_and_type_ref_index_at) all expect to be passed indices obtained
649 // directly from the bytecode.
650 // If the indices are meant to refer to fields or methods, they are
651 // actually rewritten constant pool cache indices.
652 // The routine remap_instruction_operand_from_cache manages the adjustment
653 // of these values back to constant pool indices.
654
655 // There are also "uncached" versions which do not adjust the operand index; see below.
656
657 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear.
658 // In a few cases (the verifier) there are uses before a cpcache has been built,
659 // which are handled by a dynamic check in remap_instruction_operand_from_cache.
660 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode.
661
662 // Lookup for entries consisting of (klass_index, name_and_type index)
663 Klass* klass_ref_at(int which, TRAPS);
664 Symbol* klass_ref_at_noresolve(int which);
665 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); }
666 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); }
667
668 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); }
669 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); }
670
671 // Lookup for entries consisting of (name_index, signature_index)
672 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt)
673 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt)
674
675 BasicType basic_type_for_signature_at(int which);
676
677 // Resolve string constants (to prevent allocation during compilation)
678 void resolve_string_constants(TRAPS) {
679 constantPoolHandle h_this(THREAD, this);
680 resolve_string_constants_impl(h_this, CHECK);
681 }
682
683 // CDS support
684 void remove_unshareable_info();
685 void restore_unshareable_info(TRAPS);
686 bool resolve_class_constants(TRAPS);
687 // The ConstantPool vtable is restored by this call when the ConstantPool is
688 // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for
689 // all the gory details. SA, dtrace and pstack helpers distinguish metadata
690 // by their vtable.
691 void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); }
692
693 private:
694 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 };
695 public:
696
697 // Resolve late bound constants.
698 oop resolve_constant_at(int index, TRAPS) {
699 constantPoolHandle h_this(THREAD, this);
700 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD);
701 }
702
703 oop resolve_cached_constant_at(int cache_index, TRAPS) {
704 constantPoolHandle h_this(THREAD, this);
705 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD);
706 }
707
708 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) {
709 constantPoolHandle h_this(THREAD, this);
710 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD);
711 }
712
713 oop resolve_bootstrap_specifier_at(int index, TRAPS) {
714 constantPoolHandle h_this(THREAD, this);
715 return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD);
716 }
717
718 // Klass name matches name at offset
719 bool klass_name_at_matches(instanceKlassHandle k, int which);
720
721 // Sizing
722 int length() const { return _length; }
723 void set_length(int length) { _length = length; }
724
725 // Tells whether index is within bounds.
726 bool is_within_bounds(int index) const {
727 return 0 <= index && index < length();
728 }
729
730 // Sizing (in words)
731 static int header_size() { return sizeof(ConstantPool)/HeapWordSize; }
732 static int size(int length) { return align_object_size(header_size() + length); }
733 int size() const { return size(length()); }
734 #if INCLUDE_SERVICES
735 void collect_statistics(KlassSizeStats *sz) const;
736 #endif
737
738 friend class ClassFileParser;
739 friend class SystemDictionary;
740
741 // Used by compiler to prevent classloading.
742 static Method* method_at_if_loaded (constantPoolHandle this_cp, int which);
743 static bool has_appendix_at_if_loaded (constantPoolHandle this_cp, int which);
744 static oop appendix_at_if_loaded (constantPoolHandle this_cp, int which);
745 static bool has_method_type_at_if_loaded (constantPoolHandle this_cp, int which);
746 static oop method_type_at_if_loaded (constantPoolHandle this_cp, int which);
747 static Klass* klass_at_if_loaded (constantPoolHandle this_cp, int which);
748 static Klass* klass_ref_at_if_loaded (constantPoolHandle this_cp, int which);
749
750 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
751 // future by other Java code. These take constant pool indices rather than
752 // constant pool cache indices as do the peer methods above.
753 Symbol* uncached_klass_ref_at_noresolve(int which);
754 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); }
755 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); }
756 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); }
757 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); }
758
759 // Sharing
760 int pre_resolve_shared_klasses(TRAPS);
761
762 // Debugging
763 const char* printable_name_at(int which) PRODUCT_RETURN0;
764
765 #ifdef ASSERT
766 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices
767 #else
768 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op
769 #endif //ASSERT
770
771 static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) {
772 if (invokedynamic_ok && is_invokedynamic_index(raw_index))
773 return decode_invokedynamic_index(raw_index);
774 else
775 return raw_index - CPCACHE_INDEX_TAG;
776 }
777
778 private:
779
780 void set_resolved_references(jobject s) { _resolved_references = s; }
781 Array<u2>* reference_map() const { return _reference_map; }
782 void set_reference_map(Array<u2>* o) { _reference_map = o; }
783
784 // patch JSR 292 resolved references after the class is linked.
785 void patch_resolved_references(GrowableArray<Handle>* cp_patches);
786
787 Symbol* impl_name_ref_at(int which, bool uncached);
788 Symbol* impl_signature_ref_at(int which, bool uncached);
789 int impl_klass_ref_index_at(int which, bool uncached);
790 int impl_name_and_type_ref_index_at(int which, bool uncached);
791
792 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG
793
794 // Used while constructing constant pool (only by ClassFileParser)
795 jint klass_index_at(int which) {
796 assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
797 return *int_at_addr(which);
798 }
799
800 jint string_index_at(int which) {
801 assert(tag_at(which).is_string_index(), "Corrupted constant pool");
802 return *int_at_addr(which);
803 }
804
805 // Performs the LinkResolver checks
806 static void verify_constant_pool_resolve(constantPoolHandle this_cp, KlassHandle klass, TRAPS);
807
808 // Implementation of methods that needs an exposed 'this' pointer, in order to
809 // handle GC while executing the method
810 static Klass* klass_at_impl(constantPoolHandle this_cp, int which, TRAPS);
811 static oop string_at_impl(constantPoolHandle this_cp, int which, int obj_index, TRAPS);
812
813 static void trace_class_resolution(constantPoolHandle this_cp, KlassHandle k);
814
815 // Resolve string constants (to prevent allocation during compilation)
816 static void resolve_string_constants_impl(constantPoolHandle this_cp, TRAPS);
817
818 static oop resolve_constant_at_impl(constantPoolHandle this_cp, int index, int cache_index, TRAPS);
819 static oop resolve_bootstrap_specifier_at_impl(constantPoolHandle this_cp, int index, TRAPS);
820
821 // Exception handling
822 static void throw_resolution_error(constantPoolHandle this_cp, int which, TRAPS);
823 static Symbol* exception_message(constantPoolHandle this_cp, int which, constantTag tag, oop pending_exception);
824 static void save_and_throw_exception(constantPoolHandle this_cp, int which, constantTag tag, TRAPS);
825
826 public:
827 // Merging ConstantPool* support:
828 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS);
829 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS) {
830 constantPoolHandle h_this(THREAD, this);
831 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD);
832 }
833 static void copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS);
834 static void copy_entry_to(constantPoolHandle from_cp, int from_i, constantPoolHandle to_cp, int to_i, TRAPS);
835 static void copy_operands(constantPoolHandle from_cp, constantPoolHandle to_cp, TRAPS);
836 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS);
837 int version() const { return _saved._version; }
838 void set_version(int version) { _saved._version = version; }
839 void increment_and_save_version(int version) {
840 _saved._version = version >= 0 ? (version + 1) : version; // keep overflow
841 }
842
843 void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; }
844 int resolved_reference_length() const { return _saved._resolved_reference_length; }
845
846 // Decrease ref counts of symbols that are in the constant pool
847 // when the holder class is unloaded
848 void unreference_symbols();
849
850 // Deallocate constant pool for RedefineClasses
851 void deallocate_contents(ClassLoaderData* loader_data);
852 void release_C_heap_structures();
853
854 // JVMTI accesss - GetConstantPool, RetransformClasses, ...
855 friend class JvmtiConstantPoolReconstituter;
856
857 private:
858 jint cpool_entry_size(jint idx);
859 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
860
861 // Copy cpool bytes into byte array.
862 // Returns:
863 // int > 0, count of the raw cpool bytes that have been copied
864 // 0, OutOfMemory error
865 // -1, Internal error
866 int copy_cpool_bytes(int cpool_size,
867 SymbolHashMap* tbl,
868 unsigned char *bytes);
869
870 public:
871 // Verify
872 void verify_on(outputStream* st);
873
874 // Printing
875 void print_on(outputStream* st) const;
876 void print_value_on(outputStream* st) const;
877 void print_entry_on(int index, outputStream* st);
878
879 const char* internal_name() const { return "{constant pool}"; }
880
881 #ifndef PRODUCT
882 // Compile the world support
883 static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS);
884 #endif
885 };
886
887 class SymbolHashMapEntry : public CHeapObj<mtSymbol> {
888 private:
889 unsigned int _hash; // 32-bit hash for item
890 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
891 Symbol* _symbol; // 1-st part of the mapping: symbol => value
892 u2 _value; // 2-nd part of the mapping: symbol => value
893
894 public:
895 unsigned int hash() const { return _hash; }
896 void set_hash(unsigned int hash) { _hash = hash; }
897
898 SymbolHashMapEntry* next() const { return _next; }
899 void set_next(SymbolHashMapEntry* next) { _next = next; }
900
901 Symbol* symbol() const { return _symbol; }
902 void set_symbol(Symbol* sym) { _symbol = sym; }
903
904 u2 value() const { return _value; }
905 void set_value(u2 value) { _value = value; }
906
907 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value)
908 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
909
910 }; // End SymbolHashMapEntry class
911
912
913 class SymbolHashMapBucket : public CHeapObj<mtSymbol> {
914
915 private:
916 SymbolHashMapEntry* _entry;
917
918 public:
919 SymbolHashMapEntry* entry() const { return _entry; }
920 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
921 void clear() { _entry = NULL; }
922
923 }; // End SymbolHashMapBucket class
924
925
926 class SymbolHashMap: public CHeapObj<mtSymbol> {
927
928 private:
929 // Default number of entries in the table
930 enum SymbolHashMap_Constants {
931 _Def_HashMap_Size = 256
932 };
933
934 int _table_size;
935 SymbolHashMapBucket* _buckets;
936
937 void initialize_table(int table_size) {
938 _table_size = table_size;
939 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol);
940 for (int index = 0; index < table_size; index++) {
941 _buckets[index].clear();
942 }
943 }
944
945 public:
946
947 int table_size() const { return _table_size; }
948
949 SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
950 SymbolHashMap(int table_size) { initialize_table(table_size); }
951
952 // hash P(31) from Kernighan & Ritchie
953 static unsigned int compute_hash(const char* str, int len) {
954 unsigned int hash = 0;
955 while (len-- > 0) {
956 hash = 31*hash + (unsigned) *str;
957 str++;
958 }
959 return hash;
960 }
961
962 SymbolHashMapEntry* bucket(int i) {
963 return _buckets[i].entry();
964 }
965
966 void add_entry(Symbol* sym, u2 value);
967 SymbolHashMapEntry* find_entry(Symbol* sym);
968
969 u2 symbol_to_value(Symbol* sym) {
970 SymbolHashMapEntry *entry = find_entry(sym);
971 return (entry == NULL) ? 0 : entry->value();
972 }
973
974 ~SymbolHashMap() {
975 SymbolHashMapEntry* next;
976 for (int i = 0; i < _table_size; i++) {
977 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
978 next = cur->next();
979 delete(cur);
980 }
981 }
982 delete _buckets;
983 }
984 }; // End SymbolHashMap class
985
986 #endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP