1/* 2 * Copyright (c) 1997, 2016, 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 */ 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/bytes.hpp" 35#include "utilities/constantTag.hpp" 36 37// A ConstantPool is an array containing class constants as described in the 38// class file. 39// 40// Most of the constant pool entries are written during class parsing, which 41// is safe. For klass types, the constant pool entry is 42// modified when the entry is resolved. If a klass constant pool 43// entry is read without a lock, only the resolved state guarantees that 44// the entry in the constant pool is a klass object and not a Symbol*. 45 46class SymbolHashMap; 47 48class CPSlot VALUE_OBJ_CLASS_SPEC { 49 intptr_t _ptr; 50 public: 51 enum TagBits { _resolved_value = 0, _symbol_bit = 1, _pseudo_bit = 2, _symbol_mask = 3 }; 52 53 CPSlot(intptr_t ptr): _ptr(ptr) {} 54 CPSlot(Klass* ptr): _ptr((intptr_t)ptr) {} 55 CPSlot(Symbol* ptr): _ptr((intptr_t)ptr | _symbol_bit) {} 56 CPSlot(Symbol* ptr, int tag_bits): _ptr((intptr_t)ptr | tag_bits) {} 57 58 intptr_t value() { return _ptr; } 59 bool is_resolved() { return (_ptr & _symbol_bit ) == _resolved_value; } 60 bool is_unresolved() { return (_ptr & _symbol_bit ) != _resolved_value; } 61 bool is_pseudo_string() { return (_ptr & _symbol_mask) == _symbol_bit + _pseudo_bit; } 62 63 Symbol* get_symbol() { 64 assert(is_unresolved(), "bad call"); 65 return (Symbol*)(_ptr & ~_symbol_mask); 66 } 67 Klass* get_klass() { 68 assert(is_resolved(), "bad call"); 69 return (Klass*)_ptr; 70 } 71}; 72 73class KlassSizeStats; 74 75class ConstantPool : public Metadata { 76 friend class VMStructs; 77 friend class JVMCIVMStructs; 78 friend class BytecodeInterpreter; // Directly extracts a klass in the pool for fast instanceof/checkcast 79 friend class Universe; // For null constructor 80 private: 81 Array<u1>* _tags; // the tag array describing the constant pool's contents 82 ConstantPoolCache* _cache; // the cache holding interpreter runtime information 83 InstanceKlass* _pool_holder; // the corresponding class 84 Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty 85 86 // Array of resolved objects from the constant pool and map from resolved 87 // object index to original constant pool index 88 jobject _resolved_references; 89 Array<u2>* _reference_map; 90 91 enum { 92 _has_preresolution = 1, // Flags 93 _on_stack = 2 94 }; 95 96 int _flags; // old fashioned bit twiddling 97 int _length; // number of elements in the array 98 99 union { 100 // set for CDS to restore resolved references 101 int _resolved_reference_length; 102 // keeps version number for redefined classes (used in backtrace) 103 int _version; 104 } _saved; 105 106 void set_tags(Array<u1>* tags) { _tags = tags; } 107 void tag_at_put(int which, jbyte t) { tags()->at_put(which, t); } 108 void release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); } 109 110 u1* tag_addr_at(int which) const { return tags()->adr_at(which); } 111 112 void set_operands(Array<u2>* operands) { _operands = operands; } 113 114 int flags() const { return _flags; } 115 void set_flags(int f) { _flags = f; } 116 117 private: 118 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); } 119 120 CPSlot slot_at(int which) const { 121 assert(is_within_bounds(which), "index out of bounds"); 122 // Uses volatile because the klass slot changes without a lock. 123 volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which)); 124 assert(adr != 0 || which == 0, "cp entry for klass should not be zero"); 125 return CPSlot(adr); 126 } 127 128 void slot_at_put(int which, CPSlot s) const { 129 assert(is_within_bounds(which), "index out of bounds"); 130 assert(s.value() != 0, "Caught something"); 131 *(intptr_t*)&base()[which] = s.value(); 132 } 133 intptr_t* obj_at_addr_raw(int which) const { 134 assert(is_within_bounds(which), "index out of bounds"); 135 return (intptr_t*) &base()[which]; 136 } 137 138 jint* int_at_addr(int which) const { 139 assert(is_within_bounds(which), "index out of bounds"); 140 return (jint*) &base()[which]; 141 } 142 143 jlong* long_at_addr(int which) const { 144 assert(is_within_bounds(which), "index out of bounds"); 145 return (jlong*) &base()[which]; 146 } 147 148 jfloat* float_at_addr(int which) const { 149 assert(is_within_bounds(which), "index out of bounds"); 150 return (jfloat*) &base()[which]; 151 } 152 153 jdouble* double_at_addr(int which) const { 154 assert(is_within_bounds(which), "index out of bounds"); 155 return (jdouble*) &base()[which]; 156 } 157 158 ConstantPool(Array<u1>* tags); 159 ConstantPool() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); } 160 public: 161 static ConstantPool* allocate(ClassLoaderData* loader_data, int length, TRAPS); 162 163 bool is_constantPool() const volatile { return true; } 164 165 Array<u1>* tags() const { return _tags; } 166 Array<u2>* operands() const { return _operands; } 167 168 bool has_preresolution() const { return (_flags & _has_preresolution) != 0; } 169 void set_has_preresolution() { _flags |= _has_preresolution; } 170 171 // Redefine classes support. If a method refering to this constant pool 172 // is on the executing stack, or as a handle in vm code, this constant pool 173 // can't be removed from the set of previous versions saved in the instance 174 // class. 175 bool on_stack() const { return (_flags &_on_stack) != 0; } 176 void set_on_stack(const bool value); 177 178 // Klass holding pool 179 InstanceKlass* pool_holder() const { return _pool_holder; } 180 void set_pool_holder(InstanceKlass* k) { _pool_holder = k; } 181 InstanceKlass** pool_holder_addr() { return &_pool_holder; } 182 183 // Interpreter runtime support 184 ConstantPoolCache* cache() const { return _cache; } 185 void set_cache(ConstantPoolCache* cache){ _cache = cache; } 186 187 // Create object cache in the constant pool 188 void initialize_resolved_references(ClassLoaderData* loader_data, 189 const intStack& reference_map, 190 int constant_pool_map_length, 191 TRAPS); 192 193 // resolved strings, methodHandles and callsite objects from the constant pool 194 objArrayOop resolved_references() const; 195 // mapping resolved object array indexes to cp indexes and back. 196 int object_to_cp_index(int index) { return _reference_map->at(index); } 197 int cp_to_object_index(int index); 198 199 // Invokedynamic indexes. 200 // They must look completely different from normal indexes. 201 // The main reason is that byte swapping is sometimes done on normal indexes. 202 // Finally, it is helpful for debugging to tell the two apart. 203 static bool is_invokedynamic_index(int i) { return (i < 0); } 204 static int decode_invokedynamic_index(int i) { assert(is_invokedynamic_index(i), ""); return ~i; } 205 static int encode_invokedynamic_index(int i) { assert(!is_invokedynamic_index(i), ""); return ~i; } 206 207 208 // The invokedynamic points at a CP cache entry. This entry points back 209 // at the original CP entry (CONSTANT_InvokeDynamic) and also (via f2) at an entry 210 // in the resolved_references array (which provides the appendix argument). 211 int invokedynamic_cp_cache_index(int index) const { 212 assert (is_invokedynamic_index(index), "should be a invokedynamic index"); 213 int cache_index = decode_invokedynamic_index(index); 214 return cache_index; 215 } 216 ConstantPoolCacheEntry* invokedynamic_cp_cache_entry_at(int index) const { 217 // decode index that invokedynamic points to. 218 int cp_cache_index = invokedynamic_cp_cache_index(index); 219 return cache()->entry_at(cp_cache_index); 220 } 221 222 // Assembly code support 223 static int tags_offset_in_bytes() { return offset_of(ConstantPool, _tags); } 224 static int cache_offset_in_bytes() { return offset_of(ConstantPool, _cache); } 225 static int pool_holder_offset_in_bytes() { return offset_of(ConstantPool, _pool_holder); } 226 static int resolved_references_offset_in_bytes() { return offset_of(ConstantPool, _resolved_references); } 227 228 // Storing constants 229 230 void klass_at_put(int which, Klass* k) { 231 assert(k != NULL, "resolved class shouldn't be null"); 232 assert(is_within_bounds(which), "index out of bounds"); 233 OrderAccess::release_store_ptr((Klass* volatile *)obj_at_addr_raw(which), k); 234 // The interpreter assumes when the tag is stored, the klass is resolved 235 // and the Klass* is a klass rather than a Symbol*, so we need 236 // hardware store ordering here. 237 release_tag_at_put(which, JVM_CONSTANT_Class); 238 } 239 240 // For temporary use while constructing constant pool 241 void klass_index_at_put(int which, int name_index) { 242 tag_at_put(which, JVM_CONSTANT_ClassIndex); 243 *int_at_addr(which) = name_index; 244 } 245 246 // Temporary until actual use 247 void unresolved_klass_at_put(int which, Symbol* s) { 248 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass); 249 slot_at_put(which, s); 250 } 251 252 void method_handle_index_at_put(int which, int ref_kind, int ref_index) { 253 tag_at_put(which, JVM_CONSTANT_MethodHandle); 254 *int_at_addr(which) = ((jint) ref_index<<16) | ref_kind; 255 } 256 257 void method_type_index_at_put(int which, int ref_index) { 258 tag_at_put(which, JVM_CONSTANT_MethodType); 259 *int_at_addr(which) = ref_index; 260 } 261 262 void invoke_dynamic_at_put(int which, int bootstrap_specifier_index, int name_and_type_index) { 263 tag_at_put(which, JVM_CONSTANT_InvokeDynamic); 264 *int_at_addr(which) = ((jint) name_and_type_index<<16) | bootstrap_specifier_index; 265 } 266 267 void unresolved_string_at_put(int which, Symbol* s) { 268 release_tag_at_put(which, JVM_CONSTANT_String); 269 slot_at_put(which, CPSlot(s, CPSlot::_symbol_bit)); 270 } 271 272 void int_at_put(int which, jint i) { 273 tag_at_put(which, JVM_CONSTANT_Integer); 274 *int_at_addr(which) = i; 275 } 276 277 void long_at_put(int which, jlong l) { 278 tag_at_put(which, JVM_CONSTANT_Long); 279 // *long_at_addr(which) = l; 280 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l)); 281 } 282 283 void float_at_put(int which, jfloat f) { 284 tag_at_put(which, JVM_CONSTANT_Float); 285 *float_at_addr(which) = f; 286 } 287 288 void double_at_put(int which, jdouble d) { 289 tag_at_put(which, JVM_CONSTANT_Double); 290 // *double_at_addr(which) = d; 291 // u8 temp = *(u8*) &d; 292 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d)); 293 } 294 295 Symbol** symbol_at_addr(int which) const { 296 assert(is_within_bounds(which), "index out of bounds"); 297 return (Symbol**) &base()[which]; 298 } 299 300 void symbol_at_put(int which, Symbol* s) { 301 assert(s->refcount() != 0, "should have nonzero refcount"); 302 tag_at_put(which, JVM_CONSTANT_Utf8); 303 *symbol_at_addr(which) = s; 304 } 305 306 void string_at_put(int which, int obj_index, oop str); 307 308 // For temporary use while constructing constant pool 309 void string_index_at_put(int which, int string_index) { 310 tag_at_put(which, JVM_CONSTANT_StringIndex); 311 *int_at_addr(which) = string_index; 312 } 313 314 void field_at_put(int which, int class_index, int name_and_type_index) { 315 tag_at_put(which, JVM_CONSTANT_Fieldref); 316 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 317 } 318 319 void method_at_put(int which, int class_index, int name_and_type_index) { 320 tag_at_put(which, JVM_CONSTANT_Methodref); 321 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 322 } 323 324 void interface_method_at_put(int which, int class_index, int name_and_type_index) { 325 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref); 326 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice 327 } 328 329 void name_and_type_at_put(int which, int name_index, int signature_index) { 330 tag_at_put(which, JVM_CONSTANT_NameAndType); 331 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice 332 } 333 334 // Tag query 335 336 constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); } 337 338 // Fetching constants 339 340 Klass* klass_at(int which, TRAPS) { 341 constantPoolHandle h_this(THREAD, this); 342 return klass_at_impl(h_this, which, true, THREAD); 343 } 344 345 // Version of klass_at that doesn't save the resolution error, called during deopt 346 Klass* klass_at_ignore_error(int which, TRAPS) { 347 constantPoolHandle h_this(THREAD, this); 348 return klass_at_impl(h_this, which, false, THREAD); 349 } 350 351 Symbol* klass_name_at(int which) const; // Returns the name, w/o resolving. 352 353 Klass* resolved_klass_at(int which) const { // Used by Compiler 354 guarantee(tag_at(which).is_klass(), "Corrupted constant pool"); 355 // Must do an acquire here in case another thread resolved the klass 356 // behind our back, lest we later load stale values thru the oop. 357 return CPSlot((Klass*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_klass(); 358 } 359 360 // RedefineClasses() API support: 361 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); } 362 363 jint int_at(int which) { 364 assert(tag_at(which).is_int(), "Corrupted constant pool"); 365 return *int_at_addr(which); 366 } 367 368 jlong long_at(int which) { 369 assert(tag_at(which).is_long(), "Corrupted constant pool"); 370 // return *long_at_addr(which); 371 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 372 return *((jlong*)&tmp); 373 } 374 375 jfloat float_at(int which) { 376 assert(tag_at(which).is_float(), "Corrupted constant pool"); 377 return *float_at_addr(which); 378 } 379 380 jdouble double_at(int which) { 381 assert(tag_at(which).is_double(), "Corrupted constant pool"); 382 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 383 return *((jdouble*)&tmp); 384 } 385 386 Symbol* symbol_at(int which) const { 387 assert(tag_at(which).is_utf8(), "Corrupted constant pool"); 388 return *symbol_at_addr(which); 389 } 390 391 oop string_at(int which, int obj_index, TRAPS) { 392 constantPoolHandle h_this(THREAD, this); 393 return string_at_impl(h_this, which, obj_index, THREAD); 394 } 395 oop string_at(int which, TRAPS) { 396 int obj_index = cp_to_object_index(which); 397 return string_at(which, obj_index, THREAD); 398 } 399 400 // Version that can be used before string oop array is created. 401 oop uncached_string_at(int which, TRAPS); 402 403 // A "pseudo-string" is an non-string oop that has found its way into 404 // a String entry. 405 // This can happen if the user patches a live 406 // object into a CONSTANT_String entry of an anonymous class. 407 // Method oops internally created for method handles may also 408 // use pseudo-strings to link themselves to related metaobjects. 409 410 bool is_pseudo_string_at(int which) { 411 assert(tag_at(which).is_string(), "Corrupted constant pool"); 412 return slot_at(which).is_pseudo_string(); 413 } 414 415 oop pseudo_string_at(int which, int obj_index) { 416 assert(is_pseudo_string_at(which), "must be a pseudo-string"); 417 oop s = resolved_references()->obj_at(obj_index); 418 return s; 419 } 420 421 oop pseudo_string_at(int which) { 422 assert(is_pseudo_string_at(which), "must be a pseudo-string"); 423 int obj_index = cp_to_object_index(which); 424 oop s = resolved_references()->obj_at(obj_index); 425 return s; 426 } 427 428 void pseudo_string_at_put(int which, int obj_index, oop x) { 429 assert(tag_at(which).is_string(), "Corrupted constant pool"); 430 Symbol* sym = unresolved_string_at(which); 431 slot_at_put(which, CPSlot(sym, (CPSlot::_symbol_bit | CPSlot::_pseudo_bit))); 432 string_at_put(which, obj_index, x); // this works just fine 433 } 434 435 // only called when we are sure a string entry is already resolved (via an 436 // earlier string_at call. 437 oop resolved_string_at(int which) { 438 assert(tag_at(which).is_string(), "Corrupted constant pool"); 439 // Must do an acquire here in case another thread resolved the klass 440 // behind our back, lest we later load stale values thru the oop. 441 // we might want a volatile_obj_at in ObjArrayKlass. 442 int obj_index = cp_to_object_index(which); 443 return resolved_references()->obj_at(obj_index); 444 } 445 446 Symbol* unresolved_string_at(int which) { 447 assert(tag_at(which).is_string(), "Corrupted constant pool"); 448 Symbol* sym = slot_at(which).get_symbol(); 449 return sym; 450 } 451 452 // Returns an UTF8 for a CONSTANT_String entry at a given index. 453 // UTF8 char* representation was chosen to avoid conversion of 454 // java_lang_Strings at resolved entries into Symbol*s 455 // or vice versa. 456 char* string_at_noresolve(int which); 457 458 jint name_and_type_at(int which) { 459 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool"); 460 return *int_at_addr(which); 461 } 462 463 int method_handle_ref_kind_at(int which) { 464 assert(tag_at(which).is_method_handle() || 465 tag_at(which).is_method_handle_in_error(), "Corrupted constant pool"); 466 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits 467 } 468 int method_handle_index_at(int which) { 469 assert(tag_at(which).is_method_handle() || 470 tag_at(which).is_method_handle_in_error(), "Corrupted constant pool"); 471 return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits 472 } 473 int method_type_index_at(int which) { 474 assert(tag_at(which).is_method_type() || 475 tag_at(which).is_method_type_in_error(), "Corrupted constant pool"); 476 return *int_at_addr(which); 477 } 478 479 // Derived queries: 480 Symbol* method_handle_name_ref_at(int which) { 481 int member = method_handle_index_at(which); 482 return impl_name_ref_at(member, true); 483 } 484 Symbol* method_handle_signature_ref_at(int which) { 485 int member = method_handle_index_at(which); 486 return impl_signature_ref_at(member, true); 487 } 488 int method_handle_klass_index_at(int which) { 489 int member = method_handle_index_at(which); 490 return impl_klass_ref_index_at(member, true); 491 } 492 Symbol* method_type_signature_at(int which) { 493 int sym = method_type_index_at(which); 494 return symbol_at(sym); 495 } 496 497 int invoke_dynamic_name_and_type_ref_index_at(int which) { 498 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 499 return extract_high_short_from_int(*int_at_addr(which)); 500 } 501 int invoke_dynamic_bootstrap_specifier_index(int which) { 502 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool"); 503 return extract_low_short_from_int(*int_at_addr(which)); 504 } 505 int invoke_dynamic_operand_base(int which) { 506 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 507 return operand_offset_at(operands(), bootstrap_specifier_index); 508 } 509 // The first part of the operands array consists of an index into the second part. 510 // Extract a 32-bit index value from the first part. 511 static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) { 512 int n = (bootstrap_specifier_index * 2); 513 assert(n >= 0 && n+2 <= operands->length(), "oob"); 514 // The first 32-bit index points to the beginning of the second part 515 // of the operands array. Make sure this index is in the first part. 516 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0), 517 operands->at(1))); 518 assert(second_part == 0 || n+2 <= second_part, "oob (2)"); 519 int offset = build_int_from_shorts(operands->at(n+0), 520 operands->at(n+1)); 521 // The offset itself must point into the second part of the array. 522 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)"); 523 return offset; 524 } 525 static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) { 526 int n = bootstrap_specifier_index * 2; 527 assert(n >= 0 && n+2 <= operands->length(), "oob"); 528 operands->at_put(n+0, extract_low_short_from_int(offset)); 529 operands->at_put(n+1, extract_high_short_from_int(offset)); 530 } 531 static int operand_array_length(Array<u2>* operands) { 532 if (operands == NULL || operands->length() == 0) return 0; 533 int second_part = operand_offset_at(operands, 0); 534 return (second_part / 2); 535 } 536 537#ifdef ASSERT 538 // operand tuples fit together exactly, end to end 539 static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) { 540 int nextidx = bootstrap_specifier_index + 1; 541 if (nextidx == operand_array_length(operands)) 542 return operands->length(); 543 else 544 return operand_offset_at(operands, nextidx); 545 } 546 int invoke_dynamic_operand_limit(int which) { 547 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 548 return operand_limit_at(operands(), bootstrap_specifier_index); 549 } 550#endif //ASSERT 551 552 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array): 553 enum { 554 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm 555 _indy_argc_offset = 1, // u2 argc 556 _indy_argv_offset = 2 // u2 argv[argc] 557 }; 558 559 // These functions are used in RedefineClasses for CP merge 560 561 int operand_offset_at(int bootstrap_specifier_index) { 562 assert(0 <= bootstrap_specifier_index && 563 bootstrap_specifier_index < operand_array_length(operands()), 564 "Corrupted CP operands"); 565 return operand_offset_at(operands(), bootstrap_specifier_index); 566 } 567 int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) { 568 int offset = operand_offset_at(bootstrap_specifier_index); 569 return operands()->at(offset + _indy_bsm_offset); 570 } 571 int operand_argument_count_at(int bootstrap_specifier_index) { 572 int offset = operand_offset_at(bootstrap_specifier_index); 573 int argc = operands()->at(offset + _indy_argc_offset); 574 return argc; 575 } 576 int operand_argument_index_at(int bootstrap_specifier_index, int j) { 577 int offset = operand_offset_at(bootstrap_specifier_index); 578 return operands()->at(offset + _indy_argv_offset + j); 579 } 580 int operand_next_offset_at(int bootstrap_specifier_index) { 581 int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset 582 + operand_argument_count_at(bootstrap_specifier_index); 583 return offset; 584 } 585 // Compare a bootsrap specifier in the operands arrays 586 bool compare_operand_to(int bootstrap_specifier_index1, const constantPoolHandle& cp2, 587 int bootstrap_specifier_index2, TRAPS); 588 // Find a bootsrap specifier in the operands array 589 int find_matching_operand(int bootstrap_specifier_index, const constantPoolHandle& search_cp, 590 int operands_cur_len, TRAPS); 591 // Resize the operands array with delta_len and delta_size 592 void resize_operands(int delta_len, int delta_size, TRAPS); 593 // Extend the operands array with the length and size of the ext_cp operands 594 void extend_operands(const constantPoolHandle& ext_cp, TRAPS); 595 // Shrink the operands array to a smaller array with new_len length 596 void shrink_operands(int new_len, TRAPS); 597 598 599 int invoke_dynamic_bootstrap_method_ref_index_at(int which) { 600 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 601 int op_base = invoke_dynamic_operand_base(which); 602 return operands()->at(op_base + _indy_bsm_offset); 603 } 604 int invoke_dynamic_argument_count_at(int which) { 605 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 606 int op_base = invoke_dynamic_operand_base(which); 607 int argc = operands()->at(op_base + _indy_argc_offset); 608 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc; 609 int next_offset = invoke_dynamic_operand_limit(which)); 610 assert(end_offset == next_offset, "matched ending"); 611 return argc; 612 } 613 int invoke_dynamic_argument_index_at(int which, int j) { 614 int op_base = invoke_dynamic_operand_base(which); 615 DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset)); 616 assert((uint)j < (uint)argc, "oob"); 617 return operands()->at(op_base + _indy_argv_offset + j); 618 } 619 620 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve, 621 // name_and_type_ref_index_at) all expect to be passed indices obtained 622 // directly from the bytecode. 623 // If the indices are meant to refer to fields or methods, they are 624 // actually rewritten constant pool cache indices. 625 // The routine remap_instruction_operand_from_cache manages the adjustment 626 // of these values back to constant pool indices. 627 628 // There are also "uncached" versions which do not adjust the operand index; see below. 629 630 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear. 631 // In a few cases (the verifier) there are uses before a cpcache has been built, 632 // which are handled by a dynamic check in remap_instruction_operand_from_cache. 633 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode. 634 635 // Lookup for entries consisting of (klass_index, name_and_type index) 636 Klass* klass_ref_at(int which, TRAPS); 637 Symbol* klass_ref_at_noresolve(int which); 638 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); } 639 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); } 640 641 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); } 642 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); } 643 644 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG 645 646 constantTag tag_ref_at(int cp_cache_index) { return impl_tag_ref_at(cp_cache_index, false); } 647 648 // Lookup for entries consisting of (name_index, signature_index) 649 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt) 650 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt) 651 652 BasicType basic_type_for_signature_at(int which) const; 653 654 // Resolve string constants (to prevent allocation during compilation) 655 void resolve_string_constants(TRAPS) { 656 constantPoolHandle h_this(THREAD, this); 657 resolve_string_constants_impl(h_this, CHECK); 658 } 659 660 // CDS support 661 void remove_unshareable_info(); 662 void restore_unshareable_info(TRAPS); 663 bool resolve_class_constants(TRAPS); 664 // The ConstantPool vtable is restored by this call when the ConstantPool is 665 // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for 666 // all the gory details. SA, dtrace and pstack helpers distinguish metadata 667 // by their vtable. 668 void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); } 669 670 private: 671 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 }; 672 public: 673 674 // Resolve late bound constants. 675 oop resolve_constant_at(int index, TRAPS) { 676 constantPoolHandle h_this(THREAD, this); 677 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD); 678 } 679 680 oop resolve_cached_constant_at(int cache_index, TRAPS) { 681 constantPoolHandle h_this(THREAD, this); 682 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD); 683 } 684 685 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) { 686 constantPoolHandle h_this(THREAD, this); 687 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD); 688 } 689 690 oop resolve_bootstrap_specifier_at(int index, TRAPS) { 691 constantPoolHandle h_this(THREAD, this); 692 return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD); 693 } 694 695 // Klass name matches name at offset 696 bool klass_name_at_matches(instanceKlassHandle k, int which); 697 698 // Sizing 699 int length() const { return _length; } 700 void set_length(int length) { _length = length; } 701 702 // Tells whether index is within bounds. 703 bool is_within_bounds(int index) const { 704 return 0 <= index && index < length(); 705 } 706 707 // Sizing (in words) 708 static int header_size() { 709 return align_size_up(sizeof(ConstantPool), wordSize) / wordSize; 710 } 711 static int size(int length) { return align_metadata_size(header_size() + length); } 712 int size() const { return size(length()); } 713#if INCLUDE_SERVICES 714 void collect_statistics(KlassSizeStats *sz) const; 715#endif 716 717 friend class ClassFileParser; 718 friend class SystemDictionary; 719 720 // Used by compiler to prevent classloading. 721 static Method* method_at_if_loaded (const constantPoolHandle& this_cp, int which); 722 static bool has_appendix_at_if_loaded (const constantPoolHandle& this_cp, int which); 723 static oop appendix_at_if_loaded (const constantPoolHandle& this_cp, int which); 724 static bool has_method_type_at_if_loaded (const constantPoolHandle& this_cp, int which); 725 static oop method_type_at_if_loaded (const constantPoolHandle& this_cp, int which); 726 static Klass* klass_at_if_loaded (const constantPoolHandle& this_cp, int which); 727 static Klass* klass_ref_at_if_loaded (const constantPoolHandle& this_cp, int which); 728 729 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the 730 // future by other Java code. These take constant pool indices rather than 731 // constant pool cache indices as do the peer methods above. 732 Symbol* uncached_klass_ref_at_noresolve(int which); 733 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); } 734 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); } 735 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); } 736 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); } 737 738 // Sharing 739 int pre_resolve_shared_klasses(TRAPS); 740 741 // Debugging 742 const char* printable_name_at(int which) PRODUCT_RETURN0; 743 744#ifdef ASSERT 745 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices 746#else 747 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op 748#endif //ASSERT 749 750 static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) { 751 if (invokedynamic_ok && is_invokedynamic_index(raw_index)) 752 return decode_invokedynamic_index(raw_index); 753 else 754 return raw_index - CPCACHE_INDEX_TAG; 755 } 756 757 private: 758 759 void set_resolved_references(jobject s) { _resolved_references = s; } 760 Array<u2>* reference_map() const { return _reference_map; } 761 void set_reference_map(Array<u2>* o) { _reference_map = o; } 762 763 // patch JSR 292 resolved references after the class is linked. 764 void patch_resolved_references(GrowableArray<Handle>* cp_patches); 765 766 Symbol* impl_name_ref_at(int which, bool uncached); 767 Symbol* impl_signature_ref_at(int which, bool uncached); 768 int impl_klass_ref_index_at(int which, bool uncached); 769 int impl_name_and_type_ref_index_at(int which, bool uncached); 770 constantTag impl_tag_ref_at(int which, bool uncached); 771 772 // Used while constructing constant pool (only by ClassFileParser) 773 jint klass_index_at(int which) { 774 assert(tag_at(which).is_klass_index(), "Corrupted constant pool"); 775 return *int_at_addr(which); 776 } 777 778 jint string_index_at(int which) { 779 assert(tag_at(which).is_string_index(), "Corrupted constant pool"); 780 return *int_at_addr(which); 781 } 782 783 // Performs the LinkResolver checks 784 static void verify_constant_pool_resolve(const constantPoolHandle& this_cp, KlassHandle klass, TRAPS); 785 786 // Implementation of methods that needs an exposed 'this' pointer, in order to 787 // handle GC while executing the method 788 static Klass* klass_at_impl(const constantPoolHandle& this_cp, int which, 789 bool save_resolution_error, TRAPS); 790 static oop string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS); 791 792 static void trace_class_resolution(const constantPoolHandle& this_cp, KlassHandle k); 793 794 // Resolve string constants (to prevent allocation during compilation) 795 static void resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS); 796 797 static oop resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS); 798 static oop resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS); 799 800 // Exception handling 801 static void throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS); 802 static Symbol* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception); 803 static void save_and_throw_exception(const constantPoolHandle& this_cp, int which, constantTag tag, TRAPS); 804 805 public: 806 // Merging ConstantPool* support: 807 bool compare_entry_to(int index1, const constantPoolHandle& cp2, int index2, TRAPS); 808 void copy_cp_to(int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS) { 809 constantPoolHandle h_this(THREAD, this); 810 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD); 811 } 812 static void copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS); 813 static void copy_entry_to(const constantPoolHandle& from_cp, int from_i, const constantPoolHandle& to_cp, int to_i, TRAPS); 814 static void copy_operands(const constantPoolHandle& from_cp, const constantPoolHandle& to_cp, TRAPS); 815 int find_matching_entry(int pattern_i, const constantPoolHandle& search_cp, TRAPS); 816 int version() const { return _saved._version; } 817 void set_version(int version) { _saved._version = version; } 818 void increment_and_save_version(int version) { 819 _saved._version = version >= 0 ? (version + 1) : version; // keep overflow 820 } 821 822 void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; } 823 int resolved_reference_length() const { return _saved._resolved_reference_length; } 824 825 // Decrease ref counts of symbols that are in the constant pool 826 // when the holder class is unloaded 827 void unreference_symbols(); 828 829 // Deallocate constant pool for RedefineClasses 830 void deallocate_contents(ClassLoaderData* loader_data); 831 void release_C_heap_structures(); 832 833 // JVMTI accesss - GetConstantPool, RetransformClasses, ... 834 friend class JvmtiConstantPoolReconstituter; 835 836 private: 837 jint cpool_entry_size(jint idx); 838 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap); 839 840 // Copy cpool bytes into byte array. 841 // Returns: 842 // int > 0, count of the raw cpool bytes that have been copied 843 // 0, OutOfMemory error 844 // -1, Internal error 845 int copy_cpool_bytes(int cpool_size, 846 SymbolHashMap* tbl, 847 unsigned char *bytes); 848 849 public: 850 // Verify 851 void verify_on(outputStream* st); 852 853 // Printing 854 void print_on(outputStream* st) const; 855 void print_value_on(outputStream* st) const; 856 void print_entry_on(int index, outputStream* st); 857 858 const char* internal_name() const { return "{constant pool}"; } 859 860#ifndef PRODUCT 861 // Compile the world support 862 static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS); 863#endif 864}; 865 866class SymbolHashMapEntry : public CHeapObj<mtSymbol> { 867 private: 868 unsigned int _hash; // 32-bit hash for item 869 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket 870 Symbol* _symbol; // 1-st part of the mapping: symbol => value 871 u2 _value; // 2-nd part of the mapping: symbol => value 872 873 public: 874 unsigned int hash() const { return _hash; } 875 void set_hash(unsigned int hash) { _hash = hash; } 876 877 SymbolHashMapEntry* next() const { return _next; } 878 void set_next(SymbolHashMapEntry* next) { _next = next; } 879 880 Symbol* symbol() const { return _symbol; } 881 void set_symbol(Symbol* sym) { _symbol = sym; } 882 883 u2 value() const { return _value; } 884 void set_value(u2 value) { _value = value; } 885 886 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value) 887 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {} 888 889}; // End SymbolHashMapEntry class 890 891 892class SymbolHashMapBucket : public CHeapObj<mtSymbol> { 893 894private: 895 SymbolHashMapEntry* _entry; 896 897public: 898 SymbolHashMapEntry* entry() const { return _entry; } 899 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; } 900 void clear() { _entry = NULL; } 901 902}; // End SymbolHashMapBucket class 903 904 905class SymbolHashMap: public CHeapObj<mtSymbol> { 906 907 private: 908 // Default number of entries in the table 909 enum SymbolHashMap_Constants { 910 _Def_HashMap_Size = 256 911 }; 912 913 int _table_size; 914 SymbolHashMapBucket* _buckets; 915 916 void initialize_table(int table_size) { 917 _table_size = table_size; 918 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol); 919 for (int index = 0; index < table_size; index++) { 920 _buckets[index].clear(); 921 } 922 } 923 924 public: 925 926 int table_size() const { return _table_size; } 927 928 SymbolHashMap() { initialize_table(_Def_HashMap_Size); } 929 SymbolHashMap(int table_size) { initialize_table(table_size); } 930 931 // hash P(31) from Kernighan & Ritchie 932 static unsigned int compute_hash(const char* str, int len) { 933 unsigned int hash = 0; 934 while (len-- > 0) { 935 hash = 31*hash + (unsigned) *str; 936 str++; 937 } 938 return hash; 939 } 940 941 SymbolHashMapEntry* bucket(int i) { 942 return _buckets[i].entry(); 943 } 944 945 void add_entry(Symbol* sym, u2 value); 946 SymbolHashMapEntry* find_entry(Symbol* sym); 947 948 u2 symbol_to_value(Symbol* sym) { 949 SymbolHashMapEntry *entry = find_entry(sym); 950 return (entry == NULL) ? 0 : entry->value(); 951 } 952 953 ~SymbolHashMap() { 954 SymbolHashMapEntry* next; 955 for (int i = 0; i < _table_size; i++) { 956 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) { 957 next = cur->next(); 958 delete(cur); 959 } 960 } 961 delete _buckets; 962 } 963}; // End SymbolHashMap class 964 965#endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP 966