1 /* 2 * Copyright (c) 1997, 2018, 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/constantTag.hpp" 35 #ifdef TARGET_ARCH_x86 36 # include "bytes_x86.hpp" 37 #endif 38 #ifdef TARGET_ARCH_aarch64 39 # include "bytes_aarch64.hpp" 40 #endif 41 #ifdef TARGET_ARCH_sparc 42 # include "bytes_sparc.hpp" 43 #endif 44 #ifdef TARGET_ARCH_zero 45 # include "bytes_zero.hpp" 46 #endif 47 #ifdef TARGET_ARCH_arm 48 # include "bytes_arm.hpp" 49 #endif 50 #ifdef TARGET_ARCH_ppc 51 # include "bytes_ppc.hpp" 52 #endif 53 54 // A constantPool is an array containing class constants as described in the 55 // class file. 56 // 57 // Most of the constant pool entries are written during class parsing, which 58 // is safe. For klass types, the constant pool entry is 59 // modified when the entry is resolved. If a klass constant pool 60 // entry is read without a lock, only the resolved state guarantees that 61 // the entry in the constant pool is a klass object and not a Symbol*. 62 63 class SymbolHashMap; 64 65 class CPSlot VALUE_OBJ_CLASS_SPEC { 66 intptr_t _ptr; 67 public: 68 CPSlot(intptr_t ptr): _ptr(ptr) {} 69 CPSlot(Klass* ptr): _ptr((intptr_t)ptr) {} 70 CPSlot(Symbol* ptr): _ptr((intptr_t)ptr | 1) {} 71 72 intptr_t value() { return _ptr; } 73 bool is_resolved() { return (_ptr & 1) == 0; } 74 bool is_unresolved() { return (_ptr & 1) == 1; } 75 76 Symbol* get_symbol() { 77 assert(is_unresolved(), "bad call"); 78 return (Symbol*)(_ptr & ~1); 79 } 80 Klass* get_klass() { 81 assert(is_resolved(), "bad call"); 82 return (Klass*)_ptr; 83 } 84 }; 85 86 class KlassSizeStats; 87 class ConstantPool : public Metadata { 88 friend class VMStructs; 89 friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast 90 friend class Universe; // For null constructor 91 private: 92 Array<u1>* _tags; // the tag array describing the constant pool's contents 93 ConstantPoolCache* _cache; // the cache holding interpreter runtime information 94 InstanceKlass* _pool_holder; // the corresponding class 95 Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty 96 97 // Array of resolved objects from the constant pool and map from resolved 98 // object index to original constant pool index 99 jobject _resolved_references; 100 Array<u2>* _reference_map; 101 102 enum { 103 _has_preresolution = 1, // Flags 104 _on_stack = 2 105 }; 106 107 int _flags; // old fashioned bit twiddling 108 int _length; // number of elements in the array 109 110 union { 111 // set for CDS to restore resolved references 112 int _resolved_reference_length; 113 // keeps version number for redefined classes (used in backtrace) 114 int _version; 115 } _saved; 116 117 Monitor* _lock; 118 119 void set_tags(Array<u1>* tags) { _tags = tags; } 120 void tag_at_put(int which, jbyte t) { tags()->at_put(which, t); } 121 void release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); } 122 123 void set_operands(Array<u2>* operands) { _operands = operands; } 124 125 int flags() const { return _flags; } 126 void set_flags(int f) { _flags = f; } 127 128 private: 129 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); } 130 131 CPSlot slot_at(int which) const { 132 assert(is_within_bounds(which), "index out of bounds"); 133 // Uses volatile because the klass slot changes without a lock. 134 volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which)); 135 assert(adr != 0 || which == 0, "cp entry for klass should not be zero"); 136 return CPSlot(adr); 137 } 138 139 void slot_at_put(int which, CPSlot s) const { 140 assert(is_within_bounds(which), "index out of bounds"); 141 assert(s.value() != 0, "Caught something"); 142 *(intptr_t*)&base()[which] = s.value(); 143 } 144 intptr_t* obj_at_addr_raw(int which) const { 145 assert(is_within_bounds(which), "index out of bounds"); 146 return (intptr_t*) &base()[which]; 147 } 148 149 jint* int_at_addr(int which) const { 150 assert(is_within_bounds(which), "index out of bounds"); 151 return (jint*) &base()[which]; 152 } 153 154 jlong* long_at_addr(int which) const { 155 assert(is_within_bounds(which), "index out of bounds"); 156 return (jlong*) &base()[which]; 157 } 158 159 jfloat* float_at_addr(int which) const { 160 assert(is_within_bounds(which), "index out of bounds"); 161 return (jfloat*) &base()[which]; 162 } 163 164 jdouble* double_at_addr(int which) const { 165 assert(is_within_bounds(which), "index out of bounds"); 166 return (jdouble*) &base()[which]; 167 } 168 169 ConstantPool(Array<u1>* tags); 170 ConstantPool() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); } 171 public: 172 static ConstantPool* allocate(ClassLoaderData* loader_data, int length, TRAPS); 173 174 bool is_constantPool() const volatile { return true; } 175 176 Array<u1>* tags() const { return _tags; } 177 Array<u2>* operands() const { return _operands; } 178 179 bool has_preresolution() const { return (_flags & _has_preresolution) != 0; } 180 void set_has_preresolution() { _flags |= _has_preresolution; } 181 182 // Redefine classes support. If a method refering to this constant pool 183 // is on the executing stack, or as a handle in vm code, this constant pool 184 // can't be removed from the set of previous versions saved in the instance 185 // class. 186 bool on_stack() const { return (_flags &_on_stack) != 0; } 187 void set_on_stack(const bool value); 188 189 // Klass holding pool 190 InstanceKlass* pool_holder() const { return _pool_holder; } 191 void set_pool_holder(InstanceKlass* k) { _pool_holder = k; } 192 InstanceKlass** pool_holder_addr() { return &_pool_holder; } 193 194 // Interpreter runtime support 195 ConstantPoolCache* cache() const { return _cache; } 196 void set_cache(ConstantPoolCache* cache){ _cache = cache; } 197 198 // Create object cache in the constant pool 199 void initialize_resolved_references(ClassLoaderData* loader_data, 200 intStack reference_map, 201 int constant_pool_map_length, 202 TRAPS); 203 204 // resolved strings, methodHandles and callsite objects from the constant pool 205 objArrayOop resolved_references() const; 206 objArrayOop resolved_references_or_null() const; 207 // mapping resolved object array indexes to cp indexes and back. 208 int object_to_cp_index(int index) { return _reference_map->at(index); } 209 int cp_to_object_index(int index); 210 211 // Invokedynamic indexes. 212 // They must look completely different from normal indexes. 213 // The main reason is that byte swapping is sometimes done on normal indexes. 214 // Finally, it is helpful for debugging to tell the two apart. 215 static bool is_invokedynamic_index(int i) { return (i < 0); } 216 static int decode_invokedynamic_index(int i) { assert(is_invokedynamic_index(i), ""); return ~i; } 217 static int encode_invokedynamic_index(int i) { assert(!is_invokedynamic_index(i), ""); return ~i; } 218 219 220 // The invokedynamic points at a CP cache entry. This entry points back 221 // at the original CP entry (CONSTANT_InvokeDynamic) and also (via f2) at an entry 222 // in the resolved_references array (which provides the appendix argument). 223 int invokedynamic_cp_cache_index(int index) const { 224 assert (is_invokedynamic_index(index), "should be a invokedynamic index"); 225 int cache_index = decode_invokedynamic_index(index); 226 return cache_index; 227 } 228 ConstantPoolCacheEntry* invokedynamic_cp_cache_entry_at(int index) const { 229 // decode index that invokedynamic points to. 230 int cp_cache_index = invokedynamic_cp_cache_index(index); 231 return cache()->entry_at(cp_cache_index); 232 } 233 234 // Assembly code support 235 static int tags_offset_in_bytes() { return offset_of(ConstantPool, _tags); } 236 static int cache_offset_in_bytes() { return offset_of(ConstantPool, _cache); } 237 static int pool_holder_offset_in_bytes() { return offset_of(ConstantPool, _pool_holder); } 238 static int resolved_references_offset_in_bytes() { return offset_of(ConstantPool, _resolved_references); } 239 240 // Storing constants 241 242 void klass_at_put(int which, Klass* k) { 243 assert(k != NULL, "resolved class shouldn't be null"); 244 assert(is_within_bounds(which), "index out of bounds"); 245 OrderAccess::release_store_ptr((Klass* volatile *)obj_at_addr_raw(which), k); 246 // The interpreter assumes when the tag is stored, the klass is resolved 247 // and the Klass* is a klass rather than a Symbol*, so we need 248 // hardware store ordering here. 249 release_tag_at_put(which, JVM_CONSTANT_Class); 250 } 251 252 // For temporary use while constructing constant pool 253 void klass_index_at_put(int which, int name_index) { 254 tag_at_put(which, JVM_CONSTANT_ClassIndex); 255 *int_at_addr(which) = name_index; 256 } 257 258 // Temporary until actual use 259 void unresolved_klass_at_put(int which, Symbol* s) { 260 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass); 261 slot_at_put(which, s); 262 } 263 264 void method_handle_index_at_put(int which, int ref_kind, int ref_index) { 265 tag_at_put(which, JVM_CONSTANT_MethodHandle); 266 *int_at_addr(which) = ((jint) ref_index<<16) | ref_kind; 267 } 268 269 void method_type_index_at_put(int which, int ref_index) { 270 tag_at_put(which, JVM_CONSTANT_MethodType); 271 *int_at_addr(which) = ref_index; 272 } 273 274 void invoke_dynamic_at_put(int which, int bootstrap_specifier_index, int name_and_type_index) { 275 tag_at_put(which, JVM_CONSTANT_InvokeDynamic); 276 *int_at_addr(which) = ((jint) name_and_type_index<<16) | bootstrap_specifier_index; 277 } 278 279 void unresolved_string_at_put(int which, Symbol* s) { 280 release_tag_at_put(which, JVM_CONSTANT_String); 281 *symbol_at_addr(which) = s; 282 } 283 284 void int_at_put(int which, jint i) { 285 tag_at_put(which, JVM_CONSTANT_Integer); 286 *int_at_addr(which) = i; 287 } 288 289 void long_at_put(int which, jlong l) { 290 tag_at_put(which, JVM_CONSTANT_Long); 291 // *long_at_addr(which) = l; 292 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l)); 293 } 294 295 void float_at_put(int which, jfloat f) { 296 tag_at_put(which, JVM_CONSTANT_Float); 297 *float_at_addr(which) = f; 298 } 299 300 void double_at_put(int which, jdouble d) { 301 tag_at_put(which, JVM_CONSTANT_Double); 302 // *double_at_addr(which) = d; 303 // u8 temp = *(u8*) &d; 304 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d)); 305 } 306 307 Symbol** symbol_at_addr(int which) const { 308 assert(is_within_bounds(which), "index out of bounds"); 309 return (Symbol**) &base()[which]; 310 } 311 312 void symbol_at_put(int which, Symbol* s) { 313 assert(s->refcount() != 0, "should have nonzero refcount"); 314 tag_at_put(which, JVM_CONSTANT_Utf8); 315 *symbol_at_addr(which) = s; 316 } 317 318 void string_at_put(int which, int obj_index, oop str) { 319 resolved_references()->obj_at_put(obj_index, str); 320 } 321 322 // For temporary use while constructing constant pool 323 void string_index_at_put(int which, int string_index) { 324 tag_at_put(which, JVM_CONSTANT_StringIndex); 325 *int_at_addr(which) = string_index; 326 } 327 328 void field_at_put(int which, int class_index, int name_and_type_index) { 329 tag_at_put(which, JVM_CONSTANT_Fieldref); 330 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 331 } 332 333 void method_at_put(int which, int class_index, int name_and_type_index) { 334 tag_at_put(which, JVM_CONSTANT_Methodref); 335 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; 336 } 337 338 void interface_method_at_put(int which, int class_index, int name_and_type_index) { 339 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref); 340 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice 341 } 342 343 void name_and_type_at_put(int which, int name_index, int signature_index) { 344 tag_at_put(which, JVM_CONSTANT_NameAndType); 345 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice 346 } 347 348 // Tag query 349 350 constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); } 351 352 // Fetching constants 353 354 Klass* klass_at(int which, TRAPS) { 355 constantPoolHandle h_this(THREAD, this); 356 return klass_at_impl(h_this, which, THREAD); 357 } 358 359 Symbol* klass_name_at(int which) const; // Returns the name, w/o resolving. 360 361 Klass* resolved_klass_at(int which) const { // Used by Compiler 362 guarantee(tag_at(which).is_klass(), "Corrupted constant pool"); 363 // Must do an acquire here in case another thread resolved the klass 364 // behind our back, lest we later load stale values thru the oop. 365 return CPSlot((Klass*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_klass(); 366 } 367 368 // This method should only be used with a cpool lock or during parsing or gc 369 Symbol* unresolved_klass_at(int which) { // Temporary until actual use 370 Symbol* s = CPSlot((Symbol*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_symbol(); 371 // check that the klass is still unresolved. 372 assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool"); 373 return s; 374 } 375 376 // RedefineClasses() API support: 377 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); } 378 379 jint int_at(int which) { 380 assert(tag_at(which).is_int(), "Corrupted constant pool"); 381 return *int_at_addr(which); 382 } 383 384 jlong long_at(int which) { 385 assert(tag_at(which).is_long(), "Corrupted constant pool"); 386 // return *long_at_addr(which); 387 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 388 return *((jlong*)&tmp); 389 } 390 391 jfloat float_at(int which) { 392 assert(tag_at(which).is_float(), "Corrupted constant pool"); 393 return *float_at_addr(which); 394 } 395 396 jdouble double_at(int which) { 397 assert(tag_at(which).is_double(), "Corrupted constant pool"); 398 u8 tmp = Bytes::get_native_u8((address)&base()[which]); 399 return *((jdouble*)&tmp); 400 } 401 402 Symbol* symbol_at(int which) { 403 assert(tag_at(which).is_utf8(), "Corrupted constant pool"); 404 return *symbol_at_addr(which); 405 } 406 407 oop string_at(int which, int obj_index, TRAPS) { 408 constantPoolHandle h_this(THREAD, this); 409 return string_at_impl(h_this, which, obj_index, THREAD); 410 } 411 oop string_at(int which, TRAPS) { 412 int obj_index = cp_to_object_index(which); 413 return string_at(which, obj_index, THREAD); 414 } 415 416 // Version that can be used before string oop array is created. 417 oop uncached_string_at(int which, TRAPS); 418 419 // A "pseudo-string" is an non-string oop that has found is way into 420 // a String entry. 421 // Under EnableInvokeDynamic this can happen if the user patches a live 422 // object into a CONSTANT_String entry of an anonymous class. 423 // Method oops internally created for method handles may also 424 // use pseudo-strings to link themselves to related metaobjects. 425 426 bool is_pseudo_string_at(int which) { 427 // A pseudo string is a string that doesn't have a symbol in the cpSlot 428 return unresolved_string_at(which) == NULL; 429 } 430 431 oop pseudo_string_at(int which, int obj_index) { 432 assert(tag_at(which).is_string(), "Corrupted constant pool"); 433 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol"); 434 oop s = resolved_references()->obj_at(obj_index); 435 return s; 436 } 437 438 oop pseudo_string_at(int which) { 439 assert(tag_at(which).is_string(), "Corrupted constant pool"); 440 assert(unresolved_string_at(which) == NULL, "shouldn't have symbol"); 441 int obj_index = cp_to_object_index(which); 442 oop s = resolved_references()->obj_at(obj_index); 443 return s; 444 } 445 446 void pseudo_string_at_put(int which, int obj_index, oop x) { 447 assert(EnableInvokeDynamic, ""); 448 assert(tag_at(which).is_string(), "Corrupted constant pool"); 449 unresolved_string_at_put(which, NULL); // indicates patched string 450 string_at_put(which, obj_index, x); // this works just fine 451 } 452 453 // only called when we are sure a string entry is already resolved (via an 454 // earlier string_at call. 455 oop resolved_string_at(int which) { 456 assert(tag_at(which).is_string(), "Corrupted constant pool"); 457 // Must do an acquire here in case another thread resolved the klass 458 // behind our back, lest we later load stale values thru the oop. 459 // we might want a volatile_obj_at in ObjArrayKlass. 460 int obj_index = cp_to_object_index(which); 461 return resolved_references()->obj_at(obj_index); 462 } 463 464 Symbol* unresolved_string_at(int which) { 465 assert(tag_at(which).is_string(), "Corrupted constant pool"); 466 Symbol* s = *symbol_at_addr(which); 467 return s; 468 } 469 470 // Returns an UTF8 for a CONSTANT_String entry at a given index. 471 // UTF8 char* representation was chosen to avoid conversion of 472 // java_lang_Strings at resolved entries into Symbol*s 473 // or vice versa. 474 // Caller is responsible for checking for pseudo-strings. 475 char* string_at_noresolve(int which); 476 477 jint name_and_type_at(int which) { 478 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool"); 479 return *int_at_addr(which); 480 } 481 482 private: 483 int method_handle_ref_kind_at(int which, bool error_ok) { 484 assert(tag_at(which).is_method_handle() || 485 (error_ok && tag_at(which).is_method_handle_in_error()), "Corrupted constant pool"); 486 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits 487 } 488 int method_handle_index_at(int which, bool error_ok) { 489 assert(tag_at(which).is_method_handle() || 490 (error_ok && tag_at(which).is_method_handle_in_error()), "Corrupted constant pool"); 491 return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits 492 } 493 int method_type_index_at(int which, bool error_ok) { 494 assert(tag_at(which).is_method_type() || 495 (error_ok && tag_at(which).is_method_type_in_error()), "Corrupted constant pool"); 496 return *int_at_addr(which); 497 } 498 public: 499 int method_handle_ref_kind_at(int which) { 500 return method_handle_ref_kind_at(which, false); 501 } 502 int method_handle_ref_kind_at_error_ok(int which) { 503 return method_handle_ref_kind_at(which, true); 504 } 505 int method_handle_index_at(int which) { 506 return method_handle_index_at(which, false); 507 } 508 int method_handle_index_at_error_ok(int which) { 509 return method_handle_index_at(which, true); 510 } 511 int method_type_index_at(int which) { 512 return method_type_index_at(which, false); 513 } 514 int method_type_index_at_error_ok(int which) { 515 return method_type_index_at(which, true); 516 } 517 518 // Derived queries: 519 Symbol* method_handle_name_ref_at(int which) { 520 int member = method_handle_index_at(which); 521 return impl_name_ref_at(member, true); 522 } 523 Symbol* method_handle_signature_ref_at(int which) { 524 int member = method_handle_index_at(which); 525 return impl_signature_ref_at(member, true); 526 } 527 int method_handle_klass_index_at(int which) { 528 int member = method_handle_index_at(which); 529 return impl_klass_ref_index_at(member, true); 530 } 531 Symbol* method_type_signature_at(int which) { 532 int sym = method_type_index_at(which); 533 return symbol_at(sym); 534 } 535 536 int invoke_dynamic_name_and_type_ref_index_at(int which) { 537 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 538 return extract_high_short_from_int(*int_at_addr(which)); 539 } 540 int invoke_dynamic_bootstrap_specifier_index(int which) { 541 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool"); 542 return extract_low_short_from_int(*int_at_addr(which)); 543 } 544 int invoke_dynamic_operand_base(int which) { 545 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 546 return operand_offset_at(operands(), bootstrap_specifier_index); 547 } 548 // The first part of the operands array consists of an index into the second part. 549 // Extract a 32-bit index value from the first part. 550 static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) { 551 int n = (bootstrap_specifier_index * 2); 552 assert(n >= 0 && n+2 <= operands->length(), "oob"); 553 // The first 32-bit index points to the beginning of the second part 554 // of the operands array. Make sure this index is in the first part. 555 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0), 556 operands->at(1))); 557 assert(second_part == 0 || n+2 <= second_part, "oob (2)"); 558 int offset = build_int_from_shorts(operands->at(n+0), 559 operands->at(n+1)); 560 // The offset itself must point into the second part of the array. 561 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)"); 562 return offset; 563 } 564 static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) { 565 int n = bootstrap_specifier_index * 2; 566 assert(n >= 0 && n+2 <= operands->length(), "oob"); 567 operands->at_put(n+0, extract_low_short_from_int(offset)); 568 operands->at_put(n+1, extract_high_short_from_int(offset)); 569 } 570 static int operand_array_length(Array<u2>* operands) { 571 if (operands == NULL || operands->length() == 0) return 0; 572 int second_part = operand_offset_at(operands, 0); 573 return (second_part / 2); 574 } 575 576 #ifdef ASSERT 577 // operand tuples fit together exactly, end to end 578 static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) { 579 int nextidx = bootstrap_specifier_index + 1; 580 if (nextidx == operand_array_length(operands)) 581 return operands->length(); 582 else 583 return operand_offset_at(operands, nextidx); 584 } 585 int invoke_dynamic_operand_limit(int which) { 586 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which); 587 return operand_limit_at(operands(), bootstrap_specifier_index); 588 } 589 #endif //ASSERT 590 591 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array): 592 enum { 593 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm 594 _indy_argc_offset = 1, // u2 argc 595 _indy_argv_offset = 2 // u2 argv[argc] 596 }; 597 598 // These functions are used in RedefineClasses for CP merge 599 600 int operand_offset_at(int bootstrap_specifier_index) { 601 assert(0 <= bootstrap_specifier_index && 602 bootstrap_specifier_index < operand_array_length(operands()), 603 "Corrupted CP operands"); 604 return operand_offset_at(operands(), bootstrap_specifier_index); 605 } 606 int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) { 607 int offset = operand_offset_at(bootstrap_specifier_index); 608 return operands()->at(offset + _indy_bsm_offset); 609 } 610 int operand_argument_count_at(int bootstrap_specifier_index) { 611 int offset = operand_offset_at(bootstrap_specifier_index); 612 int argc = operands()->at(offset + _indy_argc_offset); 613 return argc; 614 } 615 int operand_argument_index_at(int bootstrap_specifier_index, int j) { 616 int offset = operand_offset_at(bootstrap_specifier_index); 617 return operands()->at(offset + _indy_argv_offset + j); 618 } 619 int operand_next_offset_at(int bootstrap_specifier_index) { 620 int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset 621 + operand_argument_count_at(bootstrap_specifier_index); 622 return offset; 623 } 624 // Compare a bootsrap specifier in the operands arrays 625 bool compare_operand_to(int bootstrap_specifier_index1, constantPoolHandle cp2, 626 int bootstrap_specifier_index2, TRAPS); 627 // Find a bootsrap specifier in the operands array 628 int find_matching_operand(int bootstrap_specifier_index, constantPoolHandle search_cp, 629 int operands_cur_len, TRAPS); 630 // Resize the operands array with delta_len and delta_size 631 void resize_operands(int delta_len, int delta_size, TRAPS); 632 // Extend the operands array with the length and size of the ext_cp operands 633 void extend_operands(constantPoolHandle ext_cp, TRAPS); 634 // Shrink the operands array to a smaller array with new_len length 635 void shrink_operands(int new_len, TRAPS); 636 637 638 int invoke_dynamic_bootstrap_method_ref_index_at(int which) { 639 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 640 int op_base = invoke_dynamic_operand_base(which); 641 return operands()->at(op_base + _indy_bsm_offset); 642 } 643 int invoke_dynamic_argument_count_at(int which) { 644 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool"); 645 int op_base = invoke_dynamic_operand_base(which); 646 int argc = operands()->at(op_base + _indy_argc_offset); 647 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc; 648 int next_offset = invoke_dynamic_operand_limit(which)); 649 assert(end_offset == next_offset, "matched ending"); 650 return argc; 651 } 652 int invoke_dynamic_argument_index_at(int which, int j) { 653 int op_base = invoke_dynamic_operand_base(which); 654 DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset)); 655 assert((uint)j < (uint)argc, "oob"); 656 return operands()->at(op_base + _indy_argv_offset + j); 657 } 658 659 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve, 660 // name_and_type_ref_index_at) all expect to be passed indices obtained 661 // directly from the bytecode. 662 // If the indices are meant to refer to fields or methods, they are 663 // actually rewritten constant pool cache indices. 664 // The routine remap_instruction_operand_from_cache manages the adjustment 665 // of these values back to constant pool indices. 666 667 // There are also "uncached" versions which do not adjust the operand index; see below. 668 669 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear. 670 // In a few cases (the verifier) there are uses before a cpcache has been built, 671 // which are handled by a dynamic check in remap_instruction_operand_from_cache. 672 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode. 673 674 // Lookup for entries consisting of (klass_index, name_and_type index) 675 Klass* klass_ref_at(int which, TRAPS); 676 Symbol* klass_ref_at_noresolve(int which); 677 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); } 678 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); } 679 680 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); } 681 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); } 682 683 // Lookup for entries consisting of (name_index, signature_index) 684 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt) 685 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt) 686 687 BasicType basic_type_for_signature_at(int which); 688 689 // Resolve string constants (to prevent allocation during compilation) 690 void resolve_string_constants(TRAPS) { 691 constantPoolHandle h_this(THREAD, this); 692 resolve_string_constants_impl(h_this, CHECK); 693 } 694 695 // CDS support 696 void remove_unshareable_info(); 697 void restore_unshareable_info(TRAPS); 698 bool resolve_class_constants(TRAPS); 699 // The ConstantPool vtable is restored by this call when the ConstantPool is 700 // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for 701 // all the gory details. SA, dtrace and pstack helpers distinguish metadata 702 // by their vtable. 703 void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); } 704 705 private: 706 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 }; 707 public: 708 709 // Resolve late bound constants. 710 oop resolve_constant_at(int index, TRAPS) { 711 constantPoolHandle h_this(THREAD, this); 712 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD); 713 } 714 715 oop resolve_cached_constant_at(int cache_index, TRAPS) { 716 constantPoolHandle h_this(THREAD, this); 717 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD); 718 } 719 720 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) { 721 constantPoolHandle h_this(THREAD, this); 722 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD); 723 } 724 725 oop resolve_bootstrap_specifier_at(int index, TRAPS) { 726 constantPoolHandle h_this(THREAD, this); 727 return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD); 728 } 729 730 // Klass name matches name at offset 731 bool klass_name_at_matches(instanceKlassHandle k, int which); 732 733 // Sizing 734 int length() const { return _length; } 735 void set_length(int length) { _length = length; } 736 737 // Tells whether index is within bounds. 738 bool is_within_bounds(int index) const { 739 return 0 <= index && index < length(); 740 } 741 742 // Sizing (in words) 743 static int header_size() { return sizeof(ConstantPool)/HeapWordSize; } 744 static int size(int length) { return align_object_size(header_size() + length); } 745 int size() const { return size(length()); } 746 #if INCLUDE_SERVICES 747 void collect_statistics(KlassSizeStats *sz) const; 748 #endif 749 750 friend class ClassFileParser; 751 friend class SystemDictionary; 752 753 // Used by compiler to prevent classloading. 754 static Method* method_at_if_loaded (constantPoolHandle this_oop, int which); 755 static bool has_appendix_at_if_loaded (constantPoolHandle this_oop, int which); 756 static oop appendix_at_if_loaded (constantPoolHandle this_oop, int which); 757 static bool has_method_type_at_if_loaded (constantPoolHandle this_oop, int which); 758 static oop method_type_at_if_loaded (constantPoolHandle this_oop, int which); 759 static Klass* klass_at_if_loaded (constantPoolHandle this_oop, int which); 760 static Klass* klass_ref_at_if_loaded (constantPoolHandle this_oop, int which); 761 762 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the 763 // future by other Java code. These take constant pool indices rather than 764 // constant pool cache indices as do the peer methods above. 765 Symbol* uncached_klass_ref_at_noresolve(int which); 766 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); } 767 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); } 768 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); } 769 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); } 770 771 // Sharing 772 int pre_resolve_shared_klasses(TRAPS); 773 774 // Debugging 775 const char* printable_name_at(int which) PRODUCT_RETURN0; 776 777 #ifdef ASSERT 778 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices 779 #else 780 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op 781 #endif //ASSERT 782 783 static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) { 784 if (invokedynamic_ok && is_invokedynamic_index(raw_index)) 785 return decode_invokedynamic_index(raw_index); 786 else 787 return raw_index - CPCACHE_INDEX_TAG; 788 } 789 790 private: 791 792 void set_resolved_references(jobject s) { _resolved_references = s; } 793 Array<u2>* reference_map() const { return _reference_map; } 794 void set_reference_map(Array<u2>* o) { _reference_map = o; } 795 796 // patch JSR 292 resolved references after the class is linked. 797 void patch_resolved_references(GrowableArray<Handle>* cp_patches); 798 799 Symbol* impl_name_ref_at(int which, bool uncached); 800 Symbol* impl_signature_ref_at(int which, bool uncached); 801 int impl_klass_ref_index_at(int which, bool uncached); 802 int impl_name_and_type_ref_index_at(int which, bool uncached); 803 804 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG 805 806 // Used while constructing constant pool (only by ClassFileParser) 807 jint klass_index_at(int which) { 808 assert(tag_at(which).is_klass_index(), "Corrupted constant pool"); 809 return *int_at_addr(which); 810 } 811 812 jint string_index_at(int which) { 813 assert(tag_at(which).is_string_index(), "Corrupted constant pool"); 814 return *int_at_addr(which); 815 } 816 817 // Performs the LinkResolver checks 818 static void verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle klass, TRAPS); 819 820 // Implementation of methods that needs an exposed 'this' pointer, in order to 821 // handle GC while executing the method 822 static Klass* klass_at_impl(constantPoolHandle this_oop, int which, TRAPS); 823 static oop string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS); 824 825 // Resolve string constants (to prevent allocation during compilation) 826 static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS); 827 828 static oop resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS); 829 static oop resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS); 830 831 // Exception handling 832 static void throw_resolution_error(constantPoolHandle this_oop, int which, TRAPS); 833 static Symbol* exception_message(constantPoolHandle this_oop, int which, constantTag tag, oop pending_exception); 834 static void save_and_throw_exception(constantPoolHandle this_oop, int which, constantTag tag, TRAPS); 835 836 public: 837 // Merging ConstantPool* support: 838 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS); 839 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS) { 840 constantPoolHandle h_this(THREAD, this); 841 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD); 842 } 843 static void copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS); 844 static void copy_entry_to(constantPoolHandle from_cp, int from_i, constantPoolHandle to_cp, int to_i, TRAPS); 845 static void copy_operands(constantPoolHandle from_cp, constantPoolHandle to_cp, TRAPS); 846 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS); 847 int version() const { return _saved._version; } 848 void set_version(int version) { _saved._version = version; } 849 void increment_and_save_version(int version) { 850 _saved._version = version >= 0 ? (version + 1) : version; // keep overflow 851 } 852 853 void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; } 854 int resolved_reference_length() const { return _saved._resolved_reference_length; } 855 void set_lock(Monitor* lock) { _lock = lock; } 856 Monitor* lock() { return _lock; } 857 858 // Decrease ref counts of symbols that are in the constant pool 859 // when the holder class is unloaded 860 void unreference_symbols(); 861 862 // Deallocate constant pool for RedefineClasses 863 void deallocate_contents(ClassLoaderData* loader_data); 864 void release_C_heap_structures(); 865 866 // JVMTI accesss - GetConstantPool, RetransformClasses, ... 867 friend class JvmtiConstantPoolReconstituter; 868 869 private: 870 jint cpool_entry_size(jint idx); 871 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap); 872 873 // Copy cpool bytes into byte array. 874 // Returns: 875 // int > 0, count of the raw cpool bytes that have been copied 876 // 0, OutOfMemory error 877 // -1, Internal error 878 int copy_cpool_bytes(int cpool_size, 879 SymbolHashMap* tbl, 880 unsigned char *bytes); 881 882 public: 883 // Verify 884 void verify_on(outputStream* st); 885 886 // Printing 887 void print_on(outputStream* st) const; 888 void print_value_on(outputStream* st) const; 889 void print_entry_on(int index, outputStream* st); 890 891 const char* internal_name() const { return "{constant pool}"; } 892 893 #ifndef PRODUCT 894 // Compile the world support 895 static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS); 896 #endif 897 }; 898 899 class SymbolHashMapEntry : public CHeapObj<mtSymbol> { 900 private: 901 unsigned int _hash; // 32-bit hash for item 902 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket 903 Symbol* _symbol; // 1-st part of the mapping: symbol => value 904 u2 _value; // 2-nd part of the mapping: symbol => value 905 906 public: 907 unsigned int hash() const { return _hash; } 908 void set_hash(unsigned int hash) { _hash = hash; } 909 910 SymbolHashMapEntry* next() const { return _next; } 911 void set_next(SymbolHashMapEntry* next) { _next = next; } 912 913 Symbol* symbol() const { return _symbol; } 914 void set_symbol(Symbol* sym) { _symbol = sym; } 915 916 u2 value() const { return _value; } 917 void set_value(u2 value) { _value = value; } 918 919 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value) 920 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {} 921 922 }; // End SymbolHashMapEntry class 923 924 925 class SymbolHashMapBucket : public CHeapObj<mtSymbol> { 926 927 private: 928 SymbolHashMapEntry* _entry; 929 930 public: 931 SymbolHashMapEntry* entry() const { return _entry; } 932 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; } 933 void clear() { _entry = NULL; } 934 935 }; // End SymbolHashMapBucket class 936 937 938 class SymbolHashMap: public CHeapObj<mtSymbol> { 939 940 private: 941 // Default number of entries in the table 942 enum SymbolHashMap_Constants { 943 _Def_HashMap_Size = 256 944 }; 945 946 int _table_size; 947 SymbolHashMapBucket* _buckets; 948 949 void initialize_table(int table_size) { 950 _table_size = table_size; 951 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol); 952 for (int index = 0; index < table_size; index++) { 953 _buckets[index].clear(); 954 } 955 } 956 957 public: 958 959 int table_size() const { return _table_size; } 960 961 SymbolHashMap() { initialize_table(_Def_HashMap_Size); } 962 SymbolHashMap(int table_size) { initialize_table(table_size); } 963 964 // hash P(31) from Kernighan & Ritchie 965 static unsigned int compute_hash(const char* str, int len) { 966 unsigned int hash = 0; 967 while (len-- > 0) { 968 hash = 31*hash + (unsigned) *str; 969 str++; 970 } 971 return hash; 972 } 973 974 SymbolHashMapEntry* bucket(int i) { 975 return _buckets[i].entry(); 976 } 977 978 void add_entry(Symbol* sym, u2 value); 979 SymbolHashMapEntry* find_entry(Symbol* sym); 980 981 u2 symbol_to_value(Symbol* sym) { 982 SymbolHashMapEntry *entry = find_entry(sym); 983 return (entry == NULL) ? 0 : entry->value(); 984 } 985 986 ~SymbolHashMap() { 987 SymbolHashMapEntry* next; 988 for (int i = 0; i < _table_size; i++) { 989 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) { 990 next = cur->next(); 991 delete(cur); 992 } 993 } 994 FREE_C_HEAP_ARRAY(SymbolHashMapBucket, _buckets, mtSymbol); 995 } 996 }; // End SymbolHashMap class 997 998 #endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP