1 /* 2 * Copyright (c) 2017, 2020, 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 #include "precompiled.hpp" 26 #include "classfile/vmSymbols.hpp" 27 #include "code/codeCache.hpp" 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/collectedHeap.inline.hpp" 30 #include "gc/shared/gcLocker.inline.hpp" 31 #include "interpreter/interpreter.hpp" 32 #include "logging/log.hpp" 33 #include "memory/metaspaceClosure.hpp" 34 #include "memory/metadataFactory.hpp" 35 #include "oops/access.hpp" 36 #include "oops/compressedOops.inline.hpp" 37 #include "oops/fieldStreams.inline.hpp" 38 #include "oops/flatArrayKlass.hpp" 39 #include "oops/inlineKlass.inline.hpp" 40 #include "oops/instanceKlass.inline.hpp" 41 #include "oops/method.hpp" 42 #include "oops/oop.inline.hpp" 43 #include "oops/objArrayKlass.hpp" 44 #include "runtime/fieldDescriptor.inline.hpp" 45 #include "runtime/handles.inline.hpp" 46 #include "runtime/safepointVerifiers.hpp" 47 #include "runtime/sharedRuntime.hpp" 48 #include "runtime/signature.hpp" 49 #include "runtime/thread.inline.hpp" 50 #include "utilities/copy.hpp" 51 52 // Constructor 53 InlineKlass::InlineKlass(const ClassFileParser& parser) 54 : InstanceKlass(parser, InlineKlass::Kind) { 55 set_prototype_header(markWord::inline_type_prototype()); 56 assert(is_inline_klass(), "sanity"); 57 assert(prototype_header().is_inline_type(), "sanity"); 58 } 59 60 void InlineKlass::init_fixed_block() { 61 _adr_inlineklass_fixed_block = inlineklass_static_block(); 62 // Addresses used for inline type calling convention 63 *((Array<SigEntry>**)adr_extended_sig()) = nullptr; 64 *((Array<VMRegPair>**)adr_return_regs()) = nullptr; 65 *((address*)adr_pack_handler()) = nullptr; 66 *((address*)adr_pack_handler_jobject()) = nullptr; 67 *((address*)adr_unpack_handler()) = nullptr; 68 assert(pack_handler() == nullptr, "pack handler not null"); 69 *((int*)adr_default_value_offset()) = 0; 70 *((address*)adr_value_array_klasses()) = nullptr; 71 } 72 73 oop InlineKlass::default_value() { 74 assert(is_initialized() || is_being_initialized() || is_in_error_state(), "default value is set at the beginning of initialization"); 75 oop val = java_mirror()->obj_field_acquire(default_value_offset()); 76 assert(val != nullptr, "Sanity check"); 77 assert(oopDesc::is_oop(val), "Sanity check"); 78 assert(val->is_inline_type(), "Sanity check"); 79 assert(val->klass() == this, "sanity check"); 80 return val; 81 } 82 83 int InlineKlass::first_field_offset_old() { 84 #ifdef ASSERT 85 int first_offset = INT_MAX; 86 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 87 if (fs.offset() < first_offset) first_offset= fs.offset(); 88 } 89 #endif 90 int base_offset = instanceOopDesc::base_offset_in_bytes(); 91 // The first field of line types is aligned on a long boundary 92 base_offset = align_up(base_offset, BytesPerLong); 93 assert(base_offset == first_offset, "inconsistent offsets"); 94 return base_offset; 95 } 96 97 instanceOop InlineKlass::allocate_instance(TRAPS) { 98 int size = size_helper(); // Query before forming handle. 99 100 instanceOop oop = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 101 assert(oop->mark().is_inline_type(), "Expected inline type"); 102 return oop; 103 } 104 105 instanceOop InlineKlass::allocate_instance_buffer(TRAPS) { 106 int size = size_helper(); // Query before forming handle. 107 108 instanceOop oop = (instanceOop)Universe::heap()->obj_buffer_allocate(this, size, CHECK_NULL); 109 assert(oop->mark().is_inline_type(), "Expected inline type"); 110 return oop; 111 } 112 113 int InlineKlass::nonstatic_oop_count() { 114 int oops = 0; 115 int map_count = nonstatic_oop_map_count(); 116 OopMapBlock* block = start_of_nonstatic_oop_maps(); 117 OopMapBlock* end = block + map_count; 118 while (block != end) { 119 oops += block->count(); 120 block++; 121 } 122 return oops; 123 } 124 125 oop InlineKlass::read_flat_field(oop obj, int offset, TRAPS) { 126 oop res = nullptr; 127 assert(is_initialized() || is_being_initialized()|| is_in_error_state(), 128 "Must be initialized, initializing or in a corner case of an escaped instance of a class that failed its initialization"); 129 if (is_empty_inline_type()) { 130 res = (instanceOop)default_value(); 131 } else { 132 Handle obj_h(THREAD, obj); 133 res = allocate_instance_buffer(CHECK_NULL); 134 inline_copy_payload_to_new_oop(((char*)(oopDesc*)obj_h()) + offset, res); 135 } 136 assert(res != nullptr, "Must be set in one of two paths above"); 137 return res; 138 } 139 140 void InlineKlass::write_flat_field(oop obj, int offset, oop value, TRAPS) { 141 if (value == nullptr) { 142 THROW(vmSymbols::java_lang_NullPointerException()); 143 } 144 if (!is_empty_inline_type()) { 145 inline_copy_oop_to_payload(value, ((char*)(oopDesc*)obj) + offset); 146 } 147 } 148 149 // Arrays of... 150 151 bool InlineKlass::flat_array() { 152 if (!UseFlatArray) { 153 return false; 154 } 155 // Too big 156 int elem_bytes = get_exact_size_in_bytes(); 157 if ((FlatArrayElementMaxSize >= 0) && (elem_bytes > FlatArrayElementMaxSize)) { 158 return false; 159 } 160 // Too many embedded oops 161 if ((FlatArrayElementMaxOops >= 0) && (nonstatic_oop_count() > FlatArrayElementMaxOops)) { 162 return false; 163 } 164 // Declared atomic but not naturally atomic. 165 if (is_declared_atomic() && !is_naturally_atomic()) { 166 return false; 167 } 168 // VM enforcing InlineArrayAtomicAccess only... 169 if (InlineArrayAtomicAccess && (!is_naturally_atomic())) { 170 return false; 171 } 172 return true; 173 } 174 175 Klass* InlineKlass::value_array_klass(int n, TRAPS) { 176 if (Atomic::load_acquire(adr_value_array_klasses()) == nullptr) { 177 ResourceMark rm(THREAD); 178 JavaThread *jt = JavaThread::cast(THREAD); 179 { 180 // Atomic creation of array_klasses 181 MutexLocker ma(THREAD, MultiArray_lock); 182 183 // Check if update has already taken place 184 if (value_array_klasses() == nullptr) { 185 ArrayKlass* k; 186 if (flat_array()) { 187 k = FlatArrayKlass::allocate_klass(this, CHECK_NULL); 188 } else { 189 k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, true, true, CHECK_NULL); 190 191 } 192 // use 'release' to pair with lock-free load 193 Atomic::release_store(adr_value_array_klasses(), k); 194 } 195 } 196 } 197 ArrayKlass* ak = value_array_klasses(); 198 return ak->array_klass(n, THREAD); 199 } 200 201 Klass* InlineKlass::value_array_klass_or_null(int n) { 202 // Need load-acquire for lock-free read 203 ArrayKlass* ak = Atomic::load_acquire(adr_value_array_klasses()); 204 if (ak == nullptr) { 205 return nullptr; 206 } else { 207 return ak->array_klass_or_null(n); 208 } 209 } 210 211 Klass* InlineKlass::value_array_klass(TRAPS) { 212 return value_array_klass(1, THREAD); 213 } 214 215 Klass* InlineKlass::value_array_klass_or_null() { 216 return value_array_klass_or_null(1); 217 } 218 219 // Inline type arguments are not passed by reference, instead each 220 // field of the inline type is passed as an argument. This helper 221 // function collects the flat field (recursively) 222 // in a list. Included with the field's type is 223 // the offset of each field in the inline type: i2c and c2i adapters 224 // need that to load or store fields. Finally, the list of fields is 225 // sorted in order of increasing offsets: the adapters and the 226 // compiled code need to agree upon the order of fields. 227 // 228 // The list of basic types that is returned starts with a T_METADATA 229 // and ends with an extra T_VOID. T_METADATA/T_VOID pairs are used as 230 // delimiters. Every entry between the two is a field of the inline 231 // type. If there's an embedded inline type in the list, it also starts 232 // with a T_METADATA and ends with a T_VOID. This is so we can 233 // generate a unique fingerprint for the method's adapters and we can 234 // generate the list of basic types from the interpreter point of view 235 // (inline types passed as reference: iterate on the list until a 236 // T_METADATA, drop everything until and including the closing 237 // T_VOID) or the compiler point of view (each field of the inline 238 // types is an argument: drop all T_METADATA/T_VOID from the list). 239 int InlineKlass::collect_fields(GrowableArray<SigEntry>* sig, int base_off) { 240 int count = 0; 241 SigEntry::add_entry(sig, T_METADATA, name(), base_off); 242 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 243 if (fs.access_flags().is_static()) continue; 244 int offset = base_off + fs.offset() - (base_off > 0 ? first_field_offset() : 0); 245 if (fs.is_flat()) { 246 // Resolve klass of flat field and recursively collect fields 247 Klass* vk = get_inline_type_field_klass(fs.index()); 248 count += InlineKlass::cast(vk)->collect_fields(sig, offset); 249 } else { 250 BasicType bt = Signature::basic_type(fs.signature()); 251 if (bt == T_PRIMITIVE_OBJECT) { 252 bt = T_OBJECT; 253 } 254 SigEntry::add_entry(sig, bt, fs.signature(), offset); 255 count += type2size[bt]; 256 } 257 } 258 int offset = base_off + size_helper()*HeapWordSize - (base_off > 0 ? first_field_offset() : 0); 259 SigEntry::add_entry(sig, T_VOID, name(), offset); 260 if (base_off == 0) { 261 sig->sort(SigEntry::compare); 262 } 263 assert(sig->at(0)._bt == T_METADATA && sig->at(sig->length()-1)._bt == T_VOID, "broken structure"); 264 return count; 265 } 266 267 void InlineKlass::initialize_calling_convention(TRAPS) { 268 // Because the pack and unpack handler addresses need to be loadable from generated code, 269 // they are stored at a fixed offset in the klass metadata. Since inline type klasses do 270 // not have a vtable, the vtable offset is used to store these addresses. 271 if (InlineTypeReturnedAsFields || InlineTypePassFieldsAsArgs) { 272 ResourceMark rm; 273 GrowableArray<SigEntry> sig_vk; 274 int nb_fields = collect_fields(&sig_vk); 275 Array<SigEntry>* extended_sig = MetadataFactory::new_array<SigEntry>(class_loader_data(), sig_vk.length(), CHECK); 276 *((Array<SigEntry>**)adr_extended_sig()) = extended_sig; 277 for (int i = 0; i < sig_vk.length(); i++) { 278 extended_sig->at_put(i, sig_vk.at(i)); 279 } 280 if (can_be_returned_as_fields(/* init= */ true)) { 281 nb_fields++; 282 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, nb_fields); 283 sig_bt[0] = T_METADATA; 284 SigEntry::fill_sig_bt(&sig_vk, sig_bt+1); 285 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, nb_fields); 286 int total = SharedRuntime::java_return_convention(sig_bt, regs, nb_fields); 287 288 if (total > 0) { 289 Array<VMRegPair>* return_regs = MetadataFactory::new_array<VMRegPair>(class_loader_data(), nb_fields, CHECK); 290 *((Array<VMRegPair>**)adr_return_regs()) = return_regs; 291 for (int i = 0; i < nb_fields; i++) { 292 return_regs->at_put(i, regs[i]); 293 } 294 295 BufferedInlineTypeBlob* buffered_blob = SharedRuntime::generate_buffered_inline_type_adapter(this); 296 *((address*)adr_pack_handler()) = buffered_blob->pack_fields(); 297 *((address*)adr_pack_handler_jobject()) = buffered_blob->pack_fields_jobject(); 298 *((address*)adr_unpack_handler()) = buffered_blob->unpack_fields(); 299 assert(CodeCache::find_blob(pack_handler()) == buffered_blob, "lost track of blob"); 300 assert(can_be_returned_as_fields(), "sanity"); 301 } 302 } 303 if (!can_be_returned_as_fields() && !can_be_passed_as_fields()) { 304 MetadataFactory::free_array<SigEntry>(class_loader_data(), extended_sig); 305 assert(return_regs() == nullptr, "sanity"); 306 } 307 } 308 } 309 310 void InlineKlass::deallocate_contents(ClassLoaderData* loader_data) { 311 if (extended_sig() != nullptr) { 312 MetadataFactory::free_array<SigEntry>(loader_data, extended_sig()); 313 } 314 if (return_regs() != nullptr) { 315 MetadataFactory::free_array<VMRegPair>(loader_data, return_regs()); 316 } 317 cleanup_blobs(); 318 InstanceKlass::deallocate_contents(loader_data); 319 } 320 321 void InlineKlass::cleanup(InlineKlass* ik) { 322 ik->cleanup_blobs(); 323 } 324 325 void InlineKlass::cleanup_blobs() { 326 if (pack_handler() != nullptr) { 327 CodeBlob* buffered_blob = CodeCache::find_blob(pack_handler()); 328 assert(buffered_blob->is_buffered_inline_type_blob(), "bad blob type"); 329 BufferBlob::free((BufferBlob*)buffered_blob); 330 *((address*)adr_pack_handler()) = nullptr; 331 *((address*)adr_pack_handler_jobject()) = nullptr; 332 *((address*)adr_unpack_handler()) = nullptr; 333 } 334 } 335 336 // Can this inline type be passed as multiple values? 337 bool InlineKlass::can_be_passed_as_fields() const { 338 return InlineTypePassFieldsAsArgs; 339 } 340 341 // Can this inline type be returned as multiple values? 342 bool InlineKlass::can_be_returned_as_fields(bool init) const { 343 return InlineTypeReturnedAsFields && (init || return_regs() != nullptr); 344 } 345 346 // Create handles for all oop fields returned in registers that are going to be live across a safepoint 347 void InlineKlass::save_oop_fields(const RegisterMap& reg_map, GrowableArray<Handle>& handles) const { 348 Thread* thread = Thread::current(); 349 const Array<SigEntry>* sig_vk = extended_sig(); 350 const Array<VMRegPair>* regs = return_regs(); 351 int j = 1; 352 353 for (int i = 0; i < sig_vk->length(); i++) { 354 BasicType bt = sig_vk->at(i)._bt; 355 if (bt == T_OBJECT || bt == T_ARRAY) { 356 VMRegPair pair = regs->at(j); 357 address loc = reg_map.location(pair.first(), nullptr); 358 oop v = *(oop*)loc; 359 assert(v == nullptr || oopDesc::is_oop(v), "not an oop?"); 360 assert(Universe::heap()->is_in_or_null(v), "must be heap pointer"); 361 handles.push(Handle(thread, v)); 362 } 363 if (bt == T_METADATA) { 364 continue; 365 } 366 if (bt == T_VOID && 367 sig_vk->at(i-1)._bt != T_LONG && 368 sig_vk->at(i-1)._bt != T_DOUBLE) { 369 continue; 370 } 371 j++; 372 } 373 assert(j == regs->length(), "missed a field?"); 374 } 375 376 // Update oop fields in registers from handles after a safepoint 377 void InlineKlass::restore_oop_results(RegisterMap& reg_map, GrowableArray<Handle>& handles) const { 378 assert(InlineTypeReturnedAsFields, "Inline types should never be returned as fields"); 379 const Array<SigEntry>* sig_vk = extended_sig(); 380 const Array<VMRegPair>* regs = return_regs(); 381 assert(regs != nullptr, "inconsistent"); 382 383 int j = 1; 384 for (int i = 0, k = 0; i < sig_vk->length(); i++) { 385 BasicType bt = sig_vk->at(i)._bt; 386 if (bt == T_OBJECT || bt == T_ARRAY) { 387 VMRegPair pair = regs->at(j); 388 address loc = reg_map.location(pair.first(), nullptr); 389 *(oop*)loc = handles.at(k++)(); 390 } 391 if (bt == T_METADATA) { 392 continue; 393 } 394 if (bt == T_VOID && 395 sig_vk->at(i-1)._bt != T_LONG && 396 sig_vk->at(i-1)._bt != T_DOUBLE) { 397 continue; 398 } 399 j++; 400 } 401 assert(j == regs->length(), "missed a field?"); 402 } 403 404 // Fields are in registers. Create an instance of the inline type and 405 // initialize it with the values of the fields. 406 oop InlineKlass::realloc_result(const RegisterMap& reg_map, const GrowableArray<Handle>& handles, TRAPS) { 407 oop new_vt = allocate_instance(CHECK_NULL); 408 const Array<SigEntry>* sig_vk = extended_sig(); 409 const Array<VMRegPair>* regs = return_regs(); 410 411 int j = 1; 412 int k = 0; 413 for (int i = 0; i < sig_vk->length(); i++) { 414 BasicType bt = sig_vk->at(i)._bt; 415 if (bt == T_METADATA) { 416 continue; 417 } 418 if (bt == T_VOID) { 419 if (sig_vk->at(i-1)._bt == T_LONG || 420 sig_vk->at(i-1)._bt == T_DOUBLE) { 421 j++; 422 } 423 continue; 424 } 425 int off = sig_vk->at(i)._offset; 426 assert(off > 0, "offset in object should be positive"); 427 VMRegPair pair = regs->at(j); 428 address loc = reg_map.location(pair.first(), nullptr); 429 switch(bt) { 430 case T_BOOLEAN: { 431 new_vt->bool_field_put(off, *(jboolean*)loc); 432 break; 433 } 434 case T_CHAR: { 435 new_vt->char_field_put(off, *(jchar*)loc); 436 break; 437 } 438 case T_BYTE: { 439 new_vt->byte_field_put(off, *(jbyte*)loc); 440 break; 441 } 442 case T_SHORT: { 443 new_vt->short_field_put(off, *(jshort*)loc); 444 break; 445 } 446 case T_INT: { 447 new_vt->int_field_put(off, *(jint*)loc); 448 break; 449 } 450 case T_LONG: { 451 #ifdef _LP64 452 new_vt->double_field_put(off, *(jdouble*)loc); 453 #else 454 Unimplemented(); 455 #endif 456 break; 457 } 458 case T_OBJECT: 459 case T_ARRAY: { 460 Handle handle = handles.at(k++); 461 new_vt->obj_field_put(off, handle()); 462 break; 463 } 464 case T_FLOAT: { 465 new_vt->float_field_put(off, *(jfloat*)loc); 466 break; 467 } 468 case T_DOUBLE: { 469 new_vt->double_field_put(off, *(jdouble*)loc); 470 break; 471 } 472 default: 473 ShouldNotReachHere(); 474 } 475 *(intptr_t*)loc = 0xDEAD; 476 j++; 477 } 478 assert(j == regs->length(), "missed a field?"); 479 assert(k == handles.length(), "missed an oop?"); 480 return new_vt; 481 } 482 483 // Check the return register for an InlineKlass oop 484 InlineKlass* InlineKlass::returned_inline_klass(const RegisterMap& map) { 485 BasicType bt = T_METADATA; 486 VMRegPair pair; 487 int nb = SharedRuntime::java_return_convention(&bt, &pair, 1); 488 assert(nb == 1, "broken"); 489 490 address loc = map.location(pair.first(), nullptr); 491 intptr_t ptr = *(intptr_t*)loc; 492 if (is_set_nth_bit(ptr, 0)) { 493 // Return value is tagged, must be an InlineKlass pointer 494 clear_nth_bit(ptr, 0); 495 assert(Metaspace::contains((void*)ptr), "should be klass"); 496 InlineKlass* vk = (InlineKlass*)ptr; 497 assert(vk->can_be_returned_as_fields(), "must be able to return as fields"); 498 return vk; 499 } 500 // Return value is not tagged, must be a valid oop 501 assert(oopDesc::is_oop_or_null(cast_to_oop(ptr), true), 502 "Bad oop return: " PTR_FORMAT, ptr); 503 return nullptr; 504 } 505 506 // CDS support 507 508 void InlineKlass::metaspace_pointers_do(MetaspaceClosure* it) { 509 InstanceKlass::metaspace_pointers_do(it); 510 511 InlineKlass* this_ptr = this; 512 it->push((Klass**)adr_value_array_klasses()); 513 } 514 515 void InlineKlass::remove_unshareable_info() { 516 InstanceKlass::remove_unshareable_info(); 517 518 *((Array<SigEntry>**)adr_extended_sig()) = nullptr; 519 *((Array<VMRegPair>**)adr_return_regs()) = nullptr; 520 *((address*)adr_pack_handler()) = nullptr; 521 *((address*)adr_pack_handler_jobject()) = nullptr; 522 *((address*)adr_unpack_handler()) = nullptr; 523 assert(pack_handler() == nullptr, "pack handler not null"); 524 if (value_array_klasses() != nullptr) { 525 value_array_klasses()->remove_unshareable_info(); 526 } 527 } 528 529 void InlineKlass::remove_java_mirror() { 530 InstanceKlass::remove_java_mirror(); 531 if (value_array_klasses() != nullptr) { 532 value_array_klasses()->remove_java_mirror(); 533 } 534 } 535 536 void InlineKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS) { 537 // We are no longer bookkeeping pointer to fixed block during serialization, hence reinitializing 538 // fixed block address since its size was already accounted by InstanceKlass::size() and it will 539 // anyways be part of shared archive. 540 _adr_inlineklass_fixed_block = inlineklass_static_block(); 541 InstanceKlass::restore_unshareable_info(loader_data, protection_domain, pkg_entry, CHECK); 542 if (value_array_klasses() != nullptr) { 543 value_array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 544 } 545 } 546 547 // oop verify 548 549 void InlineKlass::verify_on(outputStream* st) { 550 InstanceKlass::verify_on(st); 551 guarantee(prototype_header().is_inline_type(), "Prototype header is not inline type"); 552 } 553 554 void InlineKlass::oop_verify_on(oop obj, outputStream* st) { 555 InstanceKlass::oop_verify_on(obj, st); 556 guarantee(obj->mark().is_inline_type(), "Header is not inline type"); 557 }