constantPool.hpp revision 9801:80f8be586fae
1/* 2 * Copyright (c) 1997, 2015, 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 resolved_references()->obj_at_put(obj_index, str); 308 } 309 310 // For temporary use while constructing constant pool 311 void string_index_at_put(int which, int string_index) { 312 tag_at_put(which, JVM_CONSTANT_StringIndex); 313 *int_at_addr(which) = string_index; 314 } 315 316 void field_at_put(int which, int class_index, int name_and_type_index) { 317 tag_at_put(which, JVM_CONSTANT_Fieldref); 318 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 319 } 320 321 void method_at_put(int which, int class_index, int name_and_type_index) { 322 tag_at_put(which, JVM_CONSTANT_Methodref); 323 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 324 } 325 326 void interface_method_at_put(int which, int class_index, int name_and_type_index) { 327 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref); 328 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice 329 } 330 331 void name_and_type_at_put(int which, int name_index, int signature_index) { 332 tag_at_put(which, JVM_CONSTANT_NameAndType); 333 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice 334 } 335 336 // Tag query 337 338 constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); } 339 340 // Fetching constants 341 342 Klass* klass_at(int which, TRAPS) { 343 constantPoolHandle h_this(THREAD, this); 344 return klass_at_impl(h_this, which, true, THREAD); 345 } 346 347 // Version of klass_at that doesn't save the resolution error, called during deopt 348 Klass* klass_at_ignore_error(int which, TRAPS) { 349 constantPoolHandle h_this(THREAD, this); 350 return klass_at_impl(h_this, which, false, THREAD); 351 } 352 353 Symbol* klass_name_at(int which) const; // Returns the name, w/o resolving. 354 355 Klass* resolved_klass_at(int which) const { // Used by Compiler 356 guarantee(tag_at(which).is_klass(), "Corrupted constant pool"); 357 // Must do an acquire here in case another thread resolved the klass 358 // behind our back, lest we later load stale values thru the oop. 359 return CPSlot((Klass*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_klass(); 360 } 361 362 // RedefineClasses() API support: 363 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); } 364 365 jint int_at(int which) { 366 assert(tag_at(which).is_int(), "Corrupted constant pool"); 367 return *int_at_addr(which); 368 } 369 370 jlong long_at(int which) { 371 assert(tag_at(which).is_long(), "Corrupted constant pool"); 372 // return *long_at_addr(which); 373 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 374 return *((jlong*)&tmp); 375 } 376 377 jfloat float_at(int which) { 378 assert(tag_at(which).is_float(), "Corrupted constant pool"); 379 return *float_at_addr(which); 380 } 381 382 jdouble double_at(int which) { 383 assert(tag_at(which).is_double(), "Corrupted constant pool"); 384 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 385 return *((jdouble*)&tmp); 386 } 387 388 Symbol* symbol_at(int which) const { 389 assert(tag_at(which).is_utf8(), "Corrupted constant pool"); 390 return *symbol_at_addr(which); 391 } 392 393 oop string_at(int which, int obj_index, TRAPS) { 394 constantPoolHandle h_this(THREAD, this); 395 return string_at_impl(h_this, which, obj_index, THREAD); 396 } 397 oop string_at(int which, TRAPS) { 398 int obj_index = cp_to_object_index(which); 399 return string_at(which, obj_index, THREAD); 400 } 401 402 // Version that can be used before string oop array is created. 403 oop uncached_string_at(int which, TRAPS); 404 405 // A "pseudo-string" is an non-string oop that has found its way into 406 // a String entry. 407 // This can happen if the user patches a live 408 // object into a CONSTANT_String entry of an anonymous class. 409 // Method oops internally created for method handles may also 410 // use pseudo-strings to link themselves to related metaobjects. 411 412 bool is_pseudo_string_at(int which) { 413 assert(tag_at(which).is_string(), "Corrupted constant pool"); 414 return slot_at(which).is_pseudo_string(); 415 } 416 417 oop pseudo_string_at(int which, int obj_index) { 418 assert(is_pseudo_string_at(which), "must be a pseudo-string"); 419 oop s = resolved_references()->obj_at(obj_index); 420 return s; 421 } 422 423 oop pseudo_string_at(int which) { 424 assert(is_pseudo_string_at(which), "must be a pseudo-string"); 425 int obj_index = cp_to_object_index(which); 426 oop s = resolved_references()->obj_at(obj_index); 427 return s; 428 } 429 430 void pseudo_string_at_put(int which, int obj_index, oop x) { 431 assert(tag_at(which).is_string(), "Corrupted constant pool"); 432 Symbol* sym = unresolved_string_at(which); 433 slot_at_put(which, CPSlot(sym, (CPSlot::_symbol_bit | CPSlot::_pseudo_bit))); 434 string_at_put(which, obj_index, x); // this works just fine 435 } 436 437 // only called when we are sure a string entry is already resolved (via an 438 // earlier string_at call. 439 oop resolved_string_at(int which) { 440 assert(tag_at(which).is_string(), "Corrupted constant pool"); 441 // Must do an acquire here in case another thread resolved the klass 442 // behind our back, lest we later load stale values thru the oop. 443 // we might want a volatile_obj_at in ObjArrayKlass. 444 int obj_index = cp_to_object_index(which); 445 return resolved_references()->obj_at(obj_index); 446 } 447 448 Symbol* unresolved_string_at(int which) { 449 assert(tag_at(which).is_string(), "Corrupted constant pool"); 450 Symbol* sym = slot_at(which).get_symbol(); 451 return sym; 452 } 453 454 // Returns an UTF8 for a CONSTANT_String entry at a given index. 455 // UTF8 char* representation was chosen to avoid conversion of 456 // java_lang_Strings at resolved entries into Symbol*s 457 // or vice versa. 458 char* string_at_noresolve(int which); 459 460 jint name_and_type_at(int which) { 461 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool"); 462 return *int_at_addr(which); 463 } 464 465 private: 466 int method_handle_ref_kind_at(int which, bool error_ok) { 467 assert(tag_at(which).is_method_handle() || 468 (error_ok && tag_at(which).is_method_handle_in_error()), "Corrupted constant pool"); 469 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits 470 } 471 int method_handle_index_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_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits 475 } 476 int method_type_index_at(int which, bool error_ok) { 477 assert(tag_at(which).is_method_type() || 478 (error_ok && tag_at(which).is_method_type_in_error()), "Corrupted constant pool"); 479 return *int_at_addr(which); 480 } 481 public: 482 int method_handle_ref_kind_at(int which) { 483 return method_handle_ref_kind_at(which, false); 484 } 485 int method_handle_ref_kind_at_error_ok(int which) { 486 return method_handle_ref_kind_at(which, true); 487 } 488 int method_handle_index_at(int which) { 489 return method_handle_index_at(which, false); 490 } 491 int method_handle_index_at_error_ok(int which) { 492 return method_handle_index_at(which, true); 493 } 494 int method_type_index_at(int which) { 495 return method_type_index_at(which, false); 496 } 497 int method_type_index_at_error_ok(int which) { 498 return method_type_index_at(which, true); 499 } 500 501 // Derived queries: 502 Symbol* method_handle_name_ref_at(int which) { 503 int member = method_handle_index_at(which); 504 return impl_name_ref_at(member, true); 505 } 506 Symbol* method_handle_signature_ref_at(int which) { 507 int member = method_handle_index_at(which); 508 return impl_signature_ref_at(member, true); 509 } 510 int method_handle_klass_index_at(int which) { 511 int member = method_handle_index_at(which); 512 return impl_klass_ref_index_at(member, true); 513 } 514 Symbol* method_type_signature_at(int which) { 515 int sym = method_type_index_at(which); 516 return symbol_at(sym); 517 } 518 519 int invoke_dynamic_name_and_type_ref_index_at(int which) { 520 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 521 return extract_high_short_from_int(*int_at_addr(which)); 522 } 523 int invoke_dynamic_bootstrap_specifier_index(int which) { 524 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool"); 525 return extract_low_short_from_int(*int_at_addr(which)); 526 } 527 int invoke_dynamic_operand_base(int which) { 528 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 529 return operand_offset_at(operands(), bootstrap_specifier_index); 530 } 531 // The first part of the operands array consists of an index into the second part. 532 // Extract a 32-bit index value from the first part. 533 static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) { 534 int n = (bootstrap_specifier_index * 2); 535 assert(n >= 0 && n+2 <= operands->length(), "oob"); 536 // The first 32-bit index points to the beginning of the second part 537 // of the operands array. Make sure this index is in the first part. 538 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0), 539 operands->at(1))); 540 assert(second_part == 0 || n+2 <= second_part, "oob (2)"); 541 int offset = build_int_from_shorts(operands->at(n+0), 542 operands->at(n+1)); 543 // The offset itself must point into the second part of the array. 544 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)"); 545 return offset; 546 } 547 static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) { 548 int n = bootstrap_specifier_index * 2; 549 assert(n >= 0 && n+2 <= operands->length(), "oob"); 550 operands->at_put(n+0, extract_low_short_from_int(offset)); 551 operands->at_put(n+1, extract_high_short_from_int(offset)); 552 } 553 static int operand_array_length(Array<u2>* operands) { 554 if (operands == NULL || operands->length() == 0) return 0; 555 int second_part = operand_offset_at(operands, 0); 556 return (second_part / 2); 557 } 558 559#ifdef ASSERT 560 // operand tuples fit together exactly, end to end 561 static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) { 562 int nextidx = bootstrap_specifier_index + 1; 563 if (nextidx == operand_array_length(operands)) 564 return operands->length(); 565 else 566 return operand_offset_at(operands, nextidx); 567 } 568 int invoke_dynamic_operand_limit(int which) { 569 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 570 return operand_limit_at(operands(), bootstrap_specifier_index); 571 } 572#endif //ASSERT 573 574 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array): 575 enum { 576 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm 577 _indy_argc_offset = 1, // u2 argc 578 _indy_argv_offset = 2 // u2 argv[argc] 579 }; 580 581 // These functions are used in RedefineClasses for CP merge 582 583 int operand_offset_at(int bootstrap_specifier_index) { 584 assert(0 <= bootstrap_specifier_index && 585 bootstrap_specifier_index < operand_array_length(operands()), 586 "Corrupted CP operands"); 587 return operand_offset_at(operands(), bootstrap_specifier_index); 588 } 589 int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) { 590 int offset = operand_offset_at(bootstrap_specifier_index); 591 return operands()->at(offset + _indy_bsm_offset); 592 } 593 int operand_argument_count_at(int bootstrap_specifier_index) { 594 int offset = operand_offset_at(bootstrap_specifier_index); 595 int argc = operands()->at(offset + _indy_argc_offset); 596 return argc; 597 } 598 int operand_argument_index_at(int bootstrap_specifier_index, int j) { 599 int offset = operand_offset_at(bootstrap_specifier_index); 600 return operands()->at(offset + _indy_argv_offset + j); 601 } 602 int operand_next_offset_at(int bootstrap_specifier_index) { 603 int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset 604 + operand_argument_count_at(bootstrap_specifier_index); 605 return offset; 606 } 607 // Compare a bootsrap specifier in the operands arrays 608 bool compare_operand_to(int bootstrap_specifier_index1, const constantPoolHandle& cp2, 609 int bootstrap_specifier_index2, TRAPS); 610 // Find a bootsrap specifier in the operands array 611 int find_matching_operand(int bootstrap_specifier_index, const constantPoolHandle& search_cp, 612 int operands_cur_len, TRAPS); 613 // Resize the operands array with delta_len and delta_size 614 void resize_operands(int delta_len, int delta_size, TRAPS); 615 // Extend the operands array with the length and size of the ext_cp operands 616 void extend_operands(const constantPoolHandle& ext_cp, TRAPS); 617 // Shrink the operands array to a smaller array with new_len length 618 void shrink_operands(int new_len, TRAPS); 619 620 621 int invoke_dynamic_bootstrap_method_ref_index_at(int which) { 622 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 623 int op_base = invoke_dynamic_operand_base(which); 624 return operands()->at(op_base + _indy_bsm_offset); 625 } 626 int invoke_dynamic_argument_count_at(int which) { 627 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 628 int op_base = invoke_dynamic_operand_base(which); 629 int argc = operands()->at(op_base + _indy_argc_offset); 630 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc; 631 int next_offset = invoke_dynamic_operand_limit(which)); 632 assert(end_offset == next_offset, "matched ending"); 633 return argc; 634 } 635 int invoke_dynamic_argument_index_at(int which, int j) { 636 int op_base = invoke_dynamic_operand_base(which); 637 DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset)); 638 assert((uint)j < (uint)argc, "oob"); 639 return operands()->at(op_base + _indy_argv_offset + j); 640 } 641 642 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve, 643 // name_and_type_ref_index_at) all expect to be passed indices obtained 644 // directly from the bytecode. 645 // If the indices are meant to refer to fields or methods, they are 646 // actually rewritten constant pool cache indices. 647 // The routine remap_instruction_operand_from_cache manages the adjustment 648 // of these values back to constant pool indices. 649 650 // There are also "uncached" versions which do not adjust the operand index; see below. 651 652 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear. 653 // In a few cases (the verifier) there are uses before a cpcache has been built, 654 // which are handled by a dynamic check in remap_instruction_operand_from_cache. 655 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode. 656 657 // Lookup for entries consisting of (klass_index, name_and_type index) 658 Klass* klass_ref_at(int which, TRAPS); 659 Symbol* klass_ref_at_noresolve(int which); 660 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); } 661 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); } 662 663 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); } 664 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); } 665 666 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG 667 668 // Lookup for entries consisting of (name_index, signature_index) 669 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt) 670 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt) 671 672 BasicType basic_type_for_signature_at(int which) const; 673 674 // Resolve string constants (to prevent allocation during compilation) 675 void resolve_string_constants(TRAPS) { 676 constantPoolHandle h_this(THREAD, this); 677 resolve_string_constants_impl(h_this, CHECK); 678 } 679 680 // CDS support 681 void remove_unshareable_info(); 682 void restore_unshareable_info(TRAPS); 683 bool resolve_class_constants(TRAPS); 684 // The ConstantPool vtable is restored by this call when the ConstantPool is 685 // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for 686 // all the gory details. SA, dtrace and pstack helpers distinguish metadata 687 // by their vtable. 688 void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); } 689 690 private: 691 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 }; 692 public: 693 694 // Resolve late bound constants. 695 oop resolve_constant_at(int index, TRAPS) { 696 constantPoolHandle h_this(THREAD, this); 697 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD); 698 } 699 700 oop resolve_cached_constant_at(int cache_index, TRAPS) { 701 constantPoolHandle h_this(THREAD, this); 702 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD); 703 } 704 705 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) { 706 constantPoolHandle h_this(THREAD, this); 707 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD); 708 } 709 710 oop resolve_bootstrap_specifier_at(int index, TRAPS) { 711 constantPoolHandle h_this(THREAD, this); 712 return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD); 713 } 714 715 // Klass name matches name at offset 716 bool klass_name_at_matches(instanceKlassHandle k, int which); 717 718 // Sizing 719 int length() const { return _length; } 720 void set_length(int length) { _length = length; } 721 722 // Tells whether index is within bounds. 723 bool is_within_bounds(int index) const { 724 return 0 <= index && index < length(); 725 } 726 727 // Sizing (in words) 728 static int header_size() { return sizeof(ConstantPool)/HeapWordSize; } 729 static int size(int length) { return align_object_size(header_size() + length); } 730 int size() const { return size(length()); } 731#if INCLUDE_SERVICES 732 void collect_statistics(KlassSizeStats *sz) const; 733#endif 734 735 friend class ClassFileParser; 736 friend class SystemDictionary; 737 738 // Used by compiler to prevent classloading. 739 static Method* method_at_if_loaded (const constantPoolHandle& this_cp, int which); 740 static bool has_appendix_at_if_loaded (const constantPoolHandle& this_cp, int which); 741 static oop appendix_at_if_loaded (const constantPoolHandle& this_cp, int which); 742 static bool has_method_type_at_if_loaded (const constantPoolHandle& this_cp, int which); 743 static oop method_type_at_if_loaded (const constantPoolHandle& this_cp, int which); 744 static Klass* klass_at_if_loaded (const constantPoolHandle& this_cp, int which); 745 static Klass* klass_ref_at_if_loaded (const constantPoolHandle& this_cp, int which); 746 747 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the 748 // future by other Java code. These take constant pool indices rather than 749 // constant pool cache indices as do the peer methods above. 750 Symbol* uncached_klass_ref_at_noresolve(int which); 751 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); } 752 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); } 753 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); } 754 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); } 755 756 // Sharing 757 int pre_resolve_shared_klasses(TRAPS); 758 759 // Debugging 760 const char* printable_name_at(int which) PRODUCT_RETURN0; 761 762#ifdef ASSERT 763 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices 764#else 765 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op 766#endif //ASSERT 767 768 static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) { 769 if (invokedynamic_ok && is_invokedynamic_index(raw_index)) 770 return decode_invokedynamic_index(raw_index); 771 else 772 return raw_index - CPCACHE_INDEX_TAG; 773 } 774 775 private: 776 777 void set_resolved_references(jobject s) { _resolved_references = s; } 778 Array<u2>* reference_map() const { return _reference_map; } 779 void set_reference_map(Array<u2>* o) { _reference_map = o; } 780 781 // patch JSR 292 resolved references after the class is linked. 782 void patch_resolved_references(GrowableArray<Handle>* cp_patches); 783 784 Symbol* impl_name_ref_at(int which, bool uncached); 785 Symbol* impl_signature_ref_at(int which, bool uncached); 786 int impl_klass_ref_index_at(int which, bool uncached); 787 int impl_name_and_type_ref_index_at(int which, bool uncached); 788 789 // Used while constructing constant pool (only by ClassFileParser) 790 jint klass_index_at(int which) { 791 assert(tag_at(which).is_klass_index(), "Corrupted constant pool"); 792 return *int_at_addr(which); 793 } 794 795 jint string_index_at(int which) { 796 assert(tag_at(which).is_string_index(), "Corrupted constant pool"); 797 return *int_at_addr(which); 798 } 799 800 // Performs the LinkResolver checks 801 static void verify_constant_pool_resolve(const constantPoolHandle& this_cp, KlassHandle klass, TRAPS); 802 803 // Implementation of methods that needs an exposed 'this' pointer, in order to 804 // handle GC while executing the method 805 static Klass* klass_at_impl(const constantPoolHandle& this_cp, int which, 806 bool save_resolution_error, TRAPS); 807 static oop string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS); 808 809 static void trace_class_resolution(const constantPoolHandle& this_cp, KlassHandle k); 810 811 // Resolve string constants (to prevent allocation during compilation) 812 static void resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS); 813 814 static oop resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS); 815 static oop resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS); 816 817 // Exception handling 818 static void throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS); 819 static Symbol* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception); 820 static void save_and_throw_exception(const constantPoolHandle& this_cp, int which, constantTag tag, TRAPS); 821 822 public: 823 // Merging ConstantPool* support: 824 bool compare_entry_to(int index1, const constantPoolHandle& cp2, int index2, TRAPS); 825 void copy_cp_to(int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS) { 826 constantPoolHandle h_this(THREAD, this); 827 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD); 828 } 829 static void copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS); 830 static void copy_entry_to(const constantPoolHandle& from_cp, int from_i, const constantPoolHandle& to_cp, int to_i, TRAPS); 831 static void copy_operands(const constantPoolHandle& from_cp, const constantPoolHandle& to_cp, TRAPS); 832 int find_matching_entry(int pattern_i, const constantPoolHandle& search_cp, TRAPS); 833 int version() const { return _saved._version; } 834 void set_version(int version) { _saved._version = version; } 835 void increment_and_save_version(int version) { 836 _saved._version = version >= 0 ? (version + 1) : version; // keep overflow 837 } 838 839 void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; } 840 int resolved_reference_length() const { return _saved._resolved_reference_length; } 841 842 // Decrease ref counts of symbols that are in the constant pool 843 // when the holder class is unloaded 844 void unreference_symbols(); 845 846 // Deallocate constant pool for RedefineClasses 847 void deallocate_contents(ClassLoaderData* loader_data); 848 void release_C_heap_structures(); 849 850 // JVMTI accesss - GetConstantPool, RetransformClasses, ... 851 friend class JvmtiConstantPoolReconstituter; 852 853 private: 854 jint cpool_entry_size(jint idx); 855 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap); 856 857 // Copy cpool bytes into byte array. 858 // Returns: 859 // int > 0, count of the raw cpool bytes that have been copied 860 // 0, OutOfMemory error 861 // -1, Internal error 862 int copy_cpool_bytes(int cpool_size, 863 SymbolHashMap* tbl, 864 unsigned char *bytes); 865 866 public: 867 // Verify 868 void verify_on(outputStream* st); 869 870 // Printing 871 void print_on(outputStream* st) const; 872 void print_value_on(outputStream* st) const; 873 void print_entry_on(int index, outputStream* st); 874 875 const char* internal_name() const { return "{constant pool}"; } 876 877#ifndef PRODUCT 878 // Compile the world support 879 static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS); 880#endif 881}; 882 883class SymbolHashMapEntry : public CHeapObj<mtSymbol> { 884 private: 885 unsigned int _hash; // 32-bit hash for item 886 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket 887 Symbol* _symbol; // 1-st part of the mapping: symbol => value 888 u2 _value; // 2-nd part of the mapping: symbol => value 889 890 public: 891 unsigned int hash() const { return _hash; } 892 void set_hash(unsigned int hash) { _hash = hash; } 893 894 SymbolHashMapEntry* next() const { return _next; } 895 void set_next(SymbolHashMapEntry* next) { _next = next; } 896 897 Symbol* symbol() const { return _symbol; } 898 void set_symbol(Symbol* sym) { _symbol = sym; } 899 900 u2 value() const { return _value; } 901 void set_value(u2 value) { _value = value; } 902 903 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value) 904 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {} 905 906}; // End SymbolHashMapEntry class 907 908 909class SymbolHashMapBucket : public CHeapObj<mtSymbol> { 910 911private: 912 SymbolHashMapEntry* _entry; 913 914public: 915 SymbolHashMapEntry* entry() const { return _entry; } 916 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; } 917 void clear() { _entry = NULL; } 918 919}; // End SymbolHashMapBucket class 920 921 922class SymbolHashMap: public CHeapObj<mtSymbol> { 923 924 private: 925 // Default number of entries in the table 926 enum SymbolHashMap_Constants { 927 _Def_HashMap_Size = 256 928 }; 929 930 int _table_size; 931 SymbolHashMapBucket* _buckets; 932 933 void initialize_table(int table_size) { 934 _table_size = table_size; 935 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol); 936 for (int index = 0; index < table_size; index++) { 937 _buckets[index].clear(); 938 } 939 } 940 941 public: 942 943 int table_size() const { return _table_size; } 944 945 SymbolHashMap() { initialize_table(_Def_HashMap_Size); } 946 SymbolHashMap(int table_size) { initialize_table(table_size); } 947 948 // hash P(31) from Kernighan & Ritchie 949 static unsigned int compute_hash(const char* str, int len) { 950 unsigned int hash = 0; 951 while (len-- > 0) { 952 hash = 31*hash + (unsigned) *str; 953 str++; 954 } 955 return hash; 956 } 957 958 SymbolHashMapEntry* bucket(int i) { 959 return _buckets[i].entry(); 960 } 961 962 void add_entry(Symbol* sym, u2 value); 963 SymbolHashMapEntry* find_entry(Symbol* sym); 964 965 u2 symbol_to_value(Symbol* sym) { 966 SymbolHashMapEntry *entry = find_entry(sym); 967 return (entry == NULL) ? 0 : entry->value(); 968 } 969 970 ~SymbolHashMap() { 971 SymbolHashMapEntry* next; 972 for (int i = 0; i < _table_size; i++) { 973 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) { 974 next = cur->next(); 975 delete(cur); 976 } 977 } 978 delete _buckets; 979 } 980}; // End SymbolHashMap class 981 982#endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP 983