Thu, 25 Apr 2013 03:58:53 -0700
8007037: JSR 292: the VM_RedefineClasses::append_entry() should do cross-checks with indy operands
Summary: References from operands to CP entries and back must be correct after CP merge
Reviewed-by: coleenp, twisti
Contributed-by: serguei.spitsyn@oracle.com
1 /*
2 * Copyright (c) 1997, 2013, 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.
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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).
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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,
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23 */
25 #ifndef SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
26 #define SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
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
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*.
60 class SymbolHashMap;
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) {}
69 intptr_t value() { return _ptr; }
70 bool is_resolved() { return (_ptr & 1) == 0; }
71 bool is_unresolved() { return (_ptr & 1) == 1; }
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 };
83 class KlassSizeStats;
84 class ConstantPool : public Metadata {
85 friend class VMStructs;
86 friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast
87 friend class Universe; // For null constructor
88 private:
89 Array<u1>* _tags; // the tag array describing the constant pool's contents
90 ConstantPoolCache* _cache; // the cache holding interpreter runtime information
91 InstanceKlass* _pool_holder; // the corresponding class
92 Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty
94 // Array of resolved objects from the constant pool and map from resolved
95 // object index to original constant pool index
96 jobject _resolved_references;
97 Array<u2>* _reference_map;
99 enum {
100 _has_preresolution = 1, // Flags
101 _on_stack = 2
102 };
104 int _flags; // old fashioned bit twiddling
105 int _length; // number of elements in the array
107 union {
108 // set for CDS to restore resolved references
109 int _resolved_reference_length;
110 // keeps version number for redefined classes (used in backtrace)
111 int _version;
112 } _saved;
114 Monitor* _lock;
116 void set_tags(Array<u1>* tags) { _tags = tags; }
117 void tag_at_put(int which, jbyte t) { tags()->at_put(which, t); }
118 void release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); }
120 void set_operands(Array<u2>* operands) { _operands = operands; }
122 int flags() const { return _flags; }
123 void set_flags(int f) { _flags = f; }
125 private:
126 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); }
128 CPSlot slot_at(int which) {
129 assert(is_within_bounds(which), "index out of bounds");
130 // Uses volatile because the klass slot changes without a lock.
131 volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which));
132 assert(adr != 0 || which == 0, "cp entry for klass should not be zero");
133 return CPSlot(adr);
134 }
136 void slot_at_put(int which, CPSlot s) const {
137 assert(is_within_bounds(which), "index out of bounds");
138 assert(s.value() != 0, "Caught something");
139 *(intptr_t*)&base()[which] = s.value();
140 }
141 intptr_t* obj_at_addr_raw(int which) const {
142 assert(is_within_bounds(which), "index out of bounds");
143 return (intptr_t*) &base()[which];
144 }
146 jint* int_at_addr(int which) const {
147 assert(is_within_bounds(which), "index out of bounds");
148 return (jint*) &base()[which];
149 }
151 jlong* long_at_addr(int which) const {
152 assert(is_within_bounds(which), "index out of bounds");
153 return (jlong*) &base()[which];
154 }
156 jfloat* float_at_addr(int which) const {
157 assert(is_within_bounds(which), "index out of bounds");
158 return (jfloat*) &base()[which];
159 }
161 jdouble* double_at_addr(int which) const {
162 assert(is_within_bounds(which), "index out of bounds");
163 return (jdouble*) &base()[which];
164 }
166 ConstantPool(Array<u1>* tags);
167 ConstantPool() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
168 public:
169 static ConstantPool* allocate(ClassLoaderData* loader_data, int length, TRAPS);
171 bool is_constantPool() const volatile { return true; }
173 Array<u1>* tags() const { return _tags; }
174 Array<u2>* operands() const { return _operands; }
176 bool has_preresolution() const { return (_flags & _has_preresolution) != 0; }
177 void set_has_preresolution() { _flags |= _has_preresolution; }
179 // Redefine classes support. If a method refering to this constant pool
180 // is on the executing stack, or as a handle in vm code, this constant pool
181 // can't be removed from the set of previous versions saved in the instance
182 // class.
183 bool on_stack() const { return (_flags &_on_stack) != 0; }
184 void set_on_stack(const bool value);
186 // Klass holding pool
187 InstanceKlass* pool_holder() const { return _pool_holder; }
188 void set_pool_holder(InstanceKlass* k) { _pool_holder = k; }
189 InstanceKlass** pool_holder_addr() { return &_pool_holder; }
191 // Interpreter runtime support
192 ConstantPoolCache* cache() const { return _cache; }
193 void set_cache(ConstantPoolCache* cache){ _cache = cache; }
195 // Create object cache in the constant pool
196 void initialize_resolved_references(ClassLoaderData* loader_data,
197 intStack reference_map,
198 int constant_pool_map_length,
199 TRAPS);
201 // resolved strings, methodHandles and callsite objects from the constant pool
202 objArrayOop resolved_references() const;
203 // mapping resolved object array indexes to cp indexes and back.
204 int object_to_cp_index(int index) { return _reference_map->at(index); }
205 int cp_to_object_index(int index);
207 // Invokedynamic indexes.
208 // They must look completely different from normal indexes.
209 // The main reason is that byte swapping is sometimes done on normal indexes.
210 // Finally, it is helpful for debugging to tell the two apart.
211 static bool is_invokedynamic_index(int i) { return (i < 0); }
212 static int decode_invokedynamic_index(int i) { assert(is_invokedynamic_index(i), ""); return ~i; }
213 static int encode_invokedynamic_index(int i) { assert(!is_invokedynamic_index(i), ""); return ~i; }
216 // The invokedynamic points at a CP cache entry. This entry points back
217 // at the original CP entry (CONSTANT_InvokeDynamic) and also (via f2) at an entry
218 // in the resolved_references array (which provides the appendix argument).
219 int invokedynamic_cp_cache_index(int index) const {
220 assert (is_invokedynamic_index(index), "should be a invokedynamic index");
221 int cache_index = decode_invokedynamic_index(index);
222 return cache_index;
223 }
224 ConstantPoolCacheEntry* invokedynamic_cp_cache_entry_at(int index) const {
225 // decode index that invokedynamic points to.
226 int cp_cache_index = invokedynamic_cp_cache_index(index);
227 return cache()->entry_at(cp_cache_index);
228 }
230 // Assembly code support
231 static int tags_offset_in_bytes() { return offset_of(ConstantPool, _tags); }
232 static int cache_offset_in_bytes() { return offset_of(ConstantPool, _cache); }
233 static int pool_holder_offset_in_bytes() { return offset_of(ConstantPool, _pool_holder); }
234 static int resolved_references_offset_in_bytes() { return offset_of(ConstantPool, _resolved_references); }
235 static int reference_map_offset_in_bytes() { return offset_of(ConstantPool, _reference_map); }
237 // Storing constants
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 }
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 }
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 }
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 }
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 }
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 }
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 }
281 void int_at_put(int which, jint i) {
282 tag_at_put(which, JVM_CONSTANT_Integer);
283 *int_at_addr(which) = i;
284 }
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 }
292 void float_at_put(int which, jfloat f) {
293 tag_at_put(which, JVM_CONSTANT_Float);
294 *float_at_addr(which) = f;
295 }
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 }
304 Symbol** symbol_at_addr(int which) const {
305 assert(is_within_bounds(which), "index out of bounds");
306 return (Symbol**) &base()[which];
307 }
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 }
315 void string_at_put(int which, int obj_index, oop str) {
316 resolved_references()->obj_at_put(obj_index, str);
317 }
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 }
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 }
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 }
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 }
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 }
345 // Tag query
347 constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); }
349 // Fetching constants
351 Klass* klass_at(int which, TRAPS) {
352 constantPoolHandle h_this(THREAD, this);
353 return klass_at_impl(h_this, which, CHECK_NULL);
354 }
356 Symbol* klass_name_at(int which); // Returns the name, w/o resolving.
358 Klass* resolved_klass_at(int which) { // 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 }
365 // This method should only be used with a cpool lock or during parsing or gc
366 Symbol* unresolved_klass_at(int which) { // Temporary until actual use
367 Symbol* s = CPSlot((Symbol*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_symbol();
368 // check that the klass is still unresolved.
369 assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool");
370 return s;
371 }
373 // RedefineClasses() API support:
374 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); }
376 jint int_at(int which) {
377 assert(tag_at(which).is_int(), "Corrupted constant pool");
378 return *int_at_addr(which);
379 }
381 jlong long_at(int which) {
382 assert(tag_at(which).is_long(), "Corrupted constant pool");
383 // return *long_at_addr(which);
384 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
385 return *((jlong*)&tmp);
386 }
388 jfloat float_at(int which) {
389 assert(tag_at(which).is_float(), "Corrupted constant pool");
390 return *float_at_addr(which);
391 }
393 jdouble double_at(int which) {
394 assert(tag_at(which).is_double(), "Corrupted constant pool");
395 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
396 return *((jdouble*)&tmp);
397 }
399 Symbol* symbol_at(int which) {
400 assert(tag_at(which).is_utf8(), "Corrupted constant pool");
401 return *symbol_at_addr(which);
402 }
404 oop string_at(int which, int obj_index, TRAPS) {
405 constantPoolHandle h_this(THREAD, this);
406 return string_at_impl(h_this, which, obj_index, THREAD);
407 }
408 oop string_at(int which, TRAPS) {
409 int obj_index = cp_to_object_index(which);
410 return string_at(which, obj_index, THREAD);
411 }
413 // Version that can be used before string oop array is created.
414 oop uncached_string_at(int which, TRAPS);
416 // A "pseudo-string" is an non-string oop that has found is way into
417 // a String entry.
418 // Under EnableInvokeDynamic this can happen if the user patches a live
419 // object into a CONSTANT_String entry of an anonymous class.
420 // Method oops internally created for method handles may also
421 // use pseudo-strings to link themselves to related metaobjects.
423 bool is_pseudo_string_at(int which) {
424 // A pseudo string is a string that doesn't have a symbol in the cpSlot
425 return unresolved_string_at(which) == NULL;
426 }
428 oop pseudo_string_at(int which, int obj_index) {
429 assert(tag_at(which).is_string(), "Corrupted constant pool");
430 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol");
431 oop s = resolved_references()->obj_at(obj_index);
432 return s;
433 }
435 oop pseudo_string_at(int which) {
436 assert(tag_at(which).is_string(), "Corrupted constant pool");
437 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol");
438 int obj_index = cp_to_object_index(which);
439 oop s = resolved_references()->obj_at(obj_index);
440 return s;
441 }
443 void pseudo_string_at_put(int which, int obj_index, oop x) {
444 assert(EnableInvokeDynamic, "");
445 assert(tag_at(which).is_string(), "Corrupted constant pool");
446 unresolved_string_at_put(which, NULL); // indicates patched string
447 string_at_put(which, obj_index, x); // this works just fine
448 }
450 // only called when we are sure a string entry is already resolved (via an
451 // earlier string_at call.
452 oop resolved_string_at(int which) {
453 assert(tag_at(which).is_string(), "Corrupted constant pool");
454 // Must do an acquire here in case another thread resolved the klass
455 // behind our back, lest we later load stale values thru the oop.
456 // we might want a volatile_obj_at in ObjArrayKlass.
457 int obj_index = cp_to_object_index(which);
458 return resolved_references()->obj_at(obj_index);
459 }
461 Symbol* unresolved_string_at(int which) {
462 assert(tag_at(which).is_string(), "Corrupted constant pool");
463 Symbol* s = *symbol_at_addr(which);
464 return s;
465 }
467 // Returns an UTF8 for a CONSTANT_String entry at a given index.
468 // UTF8 char* representation was chosen to avoid conversion of
469 // java_lang_Strings at resolved entries into Symbol*s
470 // or vice versa.
471 // Caller is responsible for checking for pseudo-strings.
472 char* string_at_noresolve(int which);
474 jint name_and_type_at(int which) {
475 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
476 return *int_at_addr(which);
477 }
479 int method_handle_ref_kind_at(int which) {
480 assert(tag_at(which).is_method_handle(), "Corrupted constant pool");
481 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits
482 }
483 int method_handle_index_at(int which) {
484 assert(tag_at(which).is_method_handle(), "Corrupted constant pool");
485 return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits
486 }
487 int method_type_index_at(int which) {
488 assert(tag_at(which).is_method_type(), "Corrupted constant pool");
489 return *int_at_addr(which);
490 }
491 // Derived queries:
492 Symbol* method_handle_name_ref_at(int which) {
493 int member = method_handle_index_at(which);
494 return impl_name_ref_at(member, true);
495 }
496 Symbol* method_handle_signature_ref_at(int which) {
497 int member = method_handle_index_at(which);
498 return impl_signature_ref_at(member, true);
499 }
500 int method_handle_klass_index_at(int which) {
501 int member = method_handle_index_at(which);
502 return impl_klass_ref_index_at(member, true);
503 }
504 Symbol* method_type_signature_at(int which) {
505 int sym = method_type_index_at(which);
506 return symbol_at(sym);
507 }
509 int invoke_dynamic_name_and_type_ref_index_at(int which) {
510 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
511 return extract_high_short_from_int(*int_at_addr(which));
512 }
513 int invoke_dynamic_bootstrap_specifier_index(int which) {
514 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool");
515 return extract_low_short_from_int(*int_at_addr(which));
516 }
517 int invoke_dynamic_operand_base(int which) {
518 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
519 return operand_offset_at(operands(), bootstrap_specifier_index);
520 }
521 // The first part of the operands array consists of an index into the second part.
522 // Extract a 32-bit index value from the first part.
523 static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) {
524 int n = (bootstrap_specifier_index * 2);
525 assert(n >= 0 && n+2 <= operands->length(), "oob");
526 // The first 32-bit index points to the beginning of the second part
527 // of the operands array. Make sure this index is in the first part.
528 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0),
529 operands->at(1)));
530 assert(second_part == 0 || n+2 <= second_part, "oob (2)");
531 int offset = build_int_from_shorts(operands->at(n+0),
532 operands->at(n+1));
533 // The offset itself must point into the second part of the array.
534 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)");
535 return offset;
536 }
537 static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) {
538 int n = bootstrap_specifier_index * 2;
539 assert(n >= 0 && n+2 <= operands->length(), "oob");
540 operands->at_put(n+0, extract_low_short_from_int(offset));
541 operands->at_put(n+1, extract_high_short_from_int(offset));
542 }
543 static int operand_array_length(Array<u2>* operands) {
544 if (operands == NULL || operands->length() == 0) return 0;
545 int second_part = operand_offset_at(operands, 0);
546 return (second_part / 2);
547 }
549 #ifdef ASSERT
550 // operand tuples fit together exactly, end to end
551 static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) {
552 int nextidx = bootstrap_specifier_index + 1;
553 if (nextidx == operand_array_length(operands))
554 return operands->length();
555 else
556 return operand_offset_at(operands, nextidx);
557 }
558 int invoke_dynamic_operand_limit(int which) {
559 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
560 return operand_limit_at(operands(), bootstrap_specifier_index);
561 }
562 #endif //ASSERT
564 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array):
565 enum {
566 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm
567 _indy_argc_offset = 1, // u2 argc
568 _indy_argv_offset = 2 // u2 argv[argc]
569 };
571 // These functions are used in RedefineClasses for CP merge
573 int operand_offset_at(int bootstrap_specifier_index) {
574 assert(0 <= bootstrap_specifier_index &&
575 bootstrap_specifier_index < operand_array_length(operands()),
576 "Corrupted CP operands");
577 return operand_offset_at(operands(), bootstrap_specifier_index);
578 }
579 int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) {
580 int offset = operand_offset_at(bootstrap_specifier_index);
581 return operands()->at(offset + _indy_bsm_offset);
582 }
583 int operand_argument_count_at(int bootstrap_specifier_index) {
584 int offset = operand_offset_at(bootstrap_specifier_index);
585 int argc = operands()->at(offset + _indy_argc_offset);
586 return argc;
587 }
588 int operand_argument_index_at(int bootstrap_specifier_index, int j) {
589 int offset = operand_offset_at(bootstrap_specifier_index);
590 return operands()->at(offset + _indy_argv_offset + j);
591 }
592 int operand_next_offset_at(int bootstrap_specifier_index) {
593 int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset
594 + operand_argument_count_at(bootstrap_specifier_index);
595 return offset;
596 }
597 // Compare a bootsrap specifier in the operands arrays
598 bool compare_operand_to(int bootstrap_specifier_index1, constantPoolHandle cp2,
599 int bootstrap_specifier_index2, TRAPS);
600 // Find a bootsrap specifier in the operands array
601 int find_matching_operand(int bootstrap_specifier_index, constantPoolHandle search_cp,
602 int operands_cur_len, TRAPS);
603 // Resize the operands array with delta_len and delta_size
604 void resize_operands(int delta_len, int delta_size, TRAPS);
605 // Extend the operands array with the length and size of the ext_cp operands
606 void extend_operands(constantPoolHandle ext_cp, TRAPS);
607 // Shrink the operands array to a smaller array with new_len length
608 void shrink_operands(int new_len, TRAPS);
611 int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
612 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
613 int op_base = invoke_dynamic_operand_base(which);
614 return operands()->at(op_base + _indy_bsm_offset);
615 }
616 int invoke_dynamic_argument_count_at(int which) {
617 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
618 int op_base = invoke_dynamic_operand_base(which);
619 int argc = operands()->at(op_base + _indy_argc_offset);
620 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc;
621 int next_offset = invoke_dynamic_operand_limit(which));
622 assert(end_offset == next_offset, "matched ending");
623 return argc;
624 }
625 int invoke_dynamic_argument_index_at(int which, int j) {
626 int op_base = invoke_dynamic_operand_base(which);
627 DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset));
628 assert((uint)j < (uint)argc, "oob");
629 return operands()->at(op_base + _indy_argv_offset + j);
630 }
632 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve,
633 // name_and_type_ref_index_at) all expect to be passed indices obtained
634 // directly from the bytecode.
635 // If the indices are meant to refer to fields or methods, they are
636 // actually rewritten constant pool cache indices.
637 // The routine remap_instruction_operand_from_cache manages the adjustment
638 // of these values back to constant pool indices.
640 // There are also "uncached" versions which do not adjust the operand index; see below.
642 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear.
643 // In a few cases (the verifier) there are uses before a cpcache has been built,
644 // which are handled by a dynamic check in remap_instruction_operand_from_cache.
645 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode.
647 // Lookup for entries consisting of (klass_index, name_and_type index)
648 Klass* klass_ref_at(int which, TRAPS);
649 Symbol* klass_ref_at_noresolve(int which);
650 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); }
651 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); }
653 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); }
654 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); }
656 // Lookup for entries consisting of (name_index, signature_index)
657 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt)
658 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt)
660 BasicType basic_type_for_signature_at(int which);
662 // Resolve string constants (to prevent allocation during compilation)
663 void resolve_string_constants(TRAPS) {
664 constantPoolHandle h_this(THREAD, this);
665 resolve_string_constants_impl(h_this, CHECK);
666 }
668 // CDS support
669 void remove_unshareable_info();
670 void restore_unshareable_info(TRAPS);
671 bool resolve_class_constants(TRAPS);
672 // The ConstantPool vtable is restored by this call when the ConstantPool is
673 // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for
674 // all the gory details. SA, dtrace and pstack helpers distinguish metadata
675 // by their vtable.
676 void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); }
678 private:
679 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 };
680 public:
682 // Resolve late bound constants.
683 oop resolve_constant_at(int index, TRAPS) {
684 constantPoolHandle h_this(THREAD, this);
685 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD);
686 }
688 oop resolve_cached_constant_at(int cache_index, TRAPS) {
689 constantPoolHandle h_this(THREAD, this);
690 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD);
691 }
693 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) {
694 constantPoolHandle h_this(THREAD, this);
695 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD);
696 }
698 oop resolve_bootstrap_specifier_at(int index, TRAPS) {
699 constantPoolHandle h_this(THREAD, this);
700 return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD);
701 }
703 // Klass name matches name at offset
704 bool klass_name_at_matches(instanceKlassHandle k, int which);
706 // Sizing
707 int length() const { return _length; }
708 void set_length(int length) { _length = length; }
710 // Tells whether index is within bounds.
711 bool is_within_bounds(int index) const {
712 return 0 <= index && index < length();
713 }
715 // Sizing (in words)
716 static int header_size() { return sizeof(ConstantPool)/HeapWordSize; }
717 static int size(int length) { return align_object_size(header_size() + length); }
718 int size() const { return size(length()); }
719 #if INCLUDE_SERVICES
720 void collect_statistics(KlassSizeStats *sz) const;
721 #endif
723 friend class ClassFileParser;
724 friend class SystemDictionary;
726 // Used by compiler to prevent classloading.
727 static Method* method_at_if_loaded (constantPoolHandle this_oop, int which);
728 static bool has_appendix_at_if_loaded (constantPoolHandle this_oop, int which);
729 static oop appendix_at_if_loaded (constantPoolHandle this_oop, int which);
730 static bool has_method_type_at_if_loaded (constantPoolHandle this_oop, int which);
731 static oop method_type_at_if_loaded (constantPoolHandle this_oop, int which);
732 static Klass* klass_at_if_loaded (constantPoolHandle this_oop, int which);
733 static Klass* klass_ref_at_if_loaded (constantPoolHandle this_oop, int which);
734 // Same as above - but does LinkResolving.
735 static Klass* klass_ref_at_if_loaded_check(constantPoolHandle this_oop, int which, TRAPS);
737 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
738 // future by other Java code. These take constant pool indices rather than
739 // constant pool cache indices as do the peer methods above.
740 Symbol* uncached_klass_ref_at_noresolve(int which);
741 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); }
742 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); }
743 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); }
744 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); }
746 // Sharing
747 int pre_resolve_shared_klasses(TRAPS);
749 // Debugging
750 const char* printable_name_at(int which) PRODUCT_RETURN0;
752 #ifdef ASSERT
753 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices
754 #else
755 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op
756 #endif //ASSERT
758 static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) {
759 if (invokedynamic_ok && is_invokedynamic_index(raw_index))
760 return decode_invokedynamic_index(raw_index);
761 else
762 return raw_index - CPCACHE_INDEX_TAG;
763 }
765 private:
767 void set_resolved_references(jobject s) { _resolved_references = s; }
768 Array<u2>* reference_map() const { return _reference_map; }
769 void set_reference_map(Array<u2>* o) { _reference_map = o; }
771 // patch JSR 292 resolved references after the class is linked.
772 void patch_resolved_references(GrowableArray<Handle>* cp_patches);
774 Symbol* impl_name_ref_at(int which, bool uncached);
775 Symbol* impl_signature_ref_at(int which, bool uncached);
776 int impl_klass_ref_index_at(int which, bool uncached);
777 int impl_name_and_type_ref_index_at(int which, bool uncached);
779 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG
781 // Used while constructing constant pool (only by ClassFileParser)
782 jint klass_index_at(int which) {
783 assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
784 return *int_at_addr(which);
785 }
787 jint string_index_at(int which) {
788 assert(tag_at(which).is_string_index(), "Corrupted constant pool");
789 return *int_at_addr(which);
790 }
792 // Performs the LinkResolver checks
793 static void verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle klass, TRAPS);
795 // Implementation of methods that needs an exposed 'this' pointer, in order to
796 // handle GC while executing the method
797 static Klass* klass_at_impl(constantPoolHandle this_oop, int which, TRAPS);
798 static oop string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS);
800 // Resolve string constants (to prevent allocation during compilation)
801 static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS);
803 static oop resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS);
804 static void save_and_throw_exception(constantPoolHandle this_oop, int which, int tag_value, TRAPS);
805 static oop resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS);
807 public:
808 // Merging ConstantPool* support:
809 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS);
810 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS) {
811 constantPoolHandle h_this(THREAD, this);
812 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD);
813 }
814 static void copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS);
815 static void copy_entry_to(constantPoolHandle from_cp, int from_i, constantPoolHandle to_cp, int to_i, TRAPS);
816 static void copy_operands(constantPoolHandle from_cp, constantPoolHandle to_cp, TRAPS);
817 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS);
818 int version() const { return _saved._version; }
819 void set_version(int version) { _saved._version = version; }
820 void increment_and_save_version(int version) {
821 _saved._version = version >= 0 ? (version + 1) : version; // keep overflow
822 }
824 void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; }
825 int resolved_reference_length() const { return _saved._resolved_reference_length; }
826 void set_lock(Monitor* lock) { _lock = lock; }
827 Monitor* lock() { return _lock; }
829 // Decrease ref counts of symbols that are in the constant pool
830 // when the holder class is unloaded
831 void unreference_symbols();
833 // Deallocate constant pool for RedefineClasses
834 void deallocate_contents(ClassLoaderData* loader_data);
835 void release_C_heap_structures();
837 // JVMTI accesss - GetConstantPool, RetransformClasses, ...
838 friend class JvmtiConstantPoolReconstituter;
840 private:
841 jint cpool_entry_size(jint idx);
842 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
844 // Copy cpool bytes into byte array.
845 // Returns:
846 // int > 0, count of the raw cpool bytes that have been copied
847 // 0, OutOfMemory error
848 // -1, Internal error
849 int copy_cpool_bytes(int cpool_size,
850 SymbolHashMap* tbl,
851 unsigned char *bytes);
853 public:
854 // Verify
855 void verify_on(outputStream* st);
857 // Printing
858 void print_on(outputStream* st) const;
859 void print_value_on(outputStream* st) const;
860 void print_entry_on(int index, outputStream* st);
862 const char* internal_name() const { return "{constant pool}"; }
864 #ifndef PRODUCT
865 // Compile the world support
866 static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS);
867 #endif
868 };
870 class SymbolHashMapEntry : public CHeapObj<mtSymbol> {
871 private:
872 unsigned int _hash; // 32-bit hash for item
873 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
874 Symbol* _symbol; // 1-st part of the mapping: symbol => value
875 u2 _value; // 2-nd part of the mapping: symbol => value
877 public:
878 unsigned int hash() const { return _hash; }
879 void set_hash(unsigned int hash) { _hash = hash; }
881 SymbolHashMapEntry* next() const { return _next; }
882 void set_next(SymbolHashMapEntry* next) { _next = next; }
884 Symbol* symbol() const { return _symbol; }
885 void set_symbol(Symbol* sym) { _symbol = sym; }
887 u2 value() const { return _value; }
888 void set_value(u2 value) { _value = value; }
890 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value)
891 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
893 }; // End SymbolHashMapEntry class
896 class SymbolHashMapBucket : public CHeapObj<mtSymbol> {
898 private:
899 SymbolHashMapEntry* _entry;
901 public:
902 SymbolHashMapEntry* entry() const { return _entry; }
903 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
904 void clear() { _entry = NULL; }
906 }; // End SymbolHashMapBucket class
909 class SymbolHashMap: public CHeapObj<mtSymbol> {
911 private:
912 // Default number of entries in the table
913 enum SymbolHashMap_Constants {
914 _Def_HashMap_Size = 256
915 };
917 int _table_size;
918 SymbolHashMapBucket* _buckets;
920 void initialize_table(int table_size) {
921 _table_size = table_size;
922 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol);
923 for (int index = 0; index < table_size; index++) {
924 _buckets[index].clear();
925 }
926 }
928 public:
930 int table_size() const { return _table_size; }
932 SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
933 SymbolHashMap(int table_size) { initialize_table(table_size); }
935 // hash P(31) from Kernighan & Ritchie
936 static unsigned int compute_hash(const char* str, int len) {
937 unsigned int hash = 0;
938 while (len-- > 0) {
939 hash = 31*hash + (unsigned) *str;
940 str++;
941 }
942 return hash;
943 }
945 SymbolHashMapEntry* bucket(int i) {
946 return _buckets[i].entry();
947 }
949 void add_entry(Symbol* sym, u2 value);
950 SymbolHashMapEntry* find_entry(Symbol* sym);
952 u2 symbol_to_value(Symbol* sym) {
953 SymbolHashMapEntry *entry = find_entry(sym);
954 return (entry == NULL) ? 0 : entry->value();
955 }
957 ~SymbolHashMap() {
958 SymbolHashMapEntry* next;
959 for (int i = 0; i < _table_size; i++) {
960 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
961 next = cur->next();
962 delete(cur);
963 }
964 }
965 delete _buckets;
966 }
967 }; // End SymbolHashMap class
969 #endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP