1 /* 2 * Copyright (c) 2017, 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 "gc/shared/barrierSet.hpp" 27 #include "gc/shared/collectedHeap.inline.hpp" 28 #include "gc/shared/gcLocker.inline.hpp" 29 #include "interpreter/interpreter.hpp" 30 #include "logging/log.hpp" 31 #include "memory/metadataFactory.hpp" 32 #include "oops/access.hpp" 33 #include "oops/compressedOops.inline.hpp" 34 #include "oops/fieldStreams.hpp" 35 #include "oops/instanceKlass.inline.hpp" 36 #include "oops/method.hpp" 37 #include "oops/oop.inline.hpp" 38 #include "oops/objArrayKlass.hpp" 39 #include "oops/valueKlass.hpp" 40 #include "oops/valueArrayKlass.hpp" 41 #include "runtime/fieldDescriptor.inline.hpp" 42 #include "runtime/handles.inline.hpp" 43 #include "runtime/safepointVerifiers.hpp" 44 #include "runtime/sharedRuntime.hpp" 45 #include "runtime/signature.hpp" 46 #include "runtime/thread.inline.hpp" 47 #include "utilities/copy.hpp" 48 49 int ValueKlass::first_field_offset() const { 50 #ifdef ASSERT 51 int first_offset = INT_MAX; 52 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 53 if (fs.offset() < first_offset) first_offset= fs.offset(); 54 } 55 #endif 56 int base_offset = instanceOopDesc::base_offset_in_bytes(); 57 // The first field of value types is aligned on a long boundary 58 base_offset = align_up(base_offset, BytesPerLong); 59 assert(base_offset == first_offset, "inconsistent offsets"); 60 return base_offset; 61 } 62 63 int ValueKlass::raw_value_byte_size() const { 64 int heapOopAlignedSize = nonstatic_field_size() << LogBytesPerHeapOop; 65 // If bigger than 64 bits or needs oop alignment, then use jlong aligned 66 // which for values should be jlong aligned, asserts in raw_field_copy otherwise 67 if (heapOopAlignedSize >= longSize || contains_oops()) { 68 return heapOopAlignedSize; 69 } 70 // Small primitives... 71 // If a few small basic type fields, return the actual size, i.e. 72 // 1 byte = 1 73 // 2 byte = 2 74 // 3 byte = 4, because pow2 needed for element stores 75 int first_offset = first_field_offset(); 76 int last_offset = 0; // find the last offset, add basic type size 77 int last_tsz = 0; 78 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 79 if (fs.access_flags().is_static()) { 80 continue; 81 } else if (fs.offset() > last_offset) { 82 BasicType type = fs.field_descriptor().field_type(); 83 if (is_java_primitive(type)) { 84 last_tsz = type2aelembytes(type); 85 } else if (type == T_VALUETYPE) { 86 // Not just primitives. Layout aligns embedded value, so use jlong aligned it is 87 return heapOopAlignedSize; 88 } else { 89 guarantee(0, "Unknown type %d", type); 90 } 91 assert(last_tsz != 0, "Invariant"); 92 last_offset = fs.offset(); 93 } 94 } 95 // Assumes VT with no fields are meaningless and illegal 96 last_offset += last_tsz; 97 assert(last_offset > first_offset && last_tsz, "Invariant"); 98 return 1 << upper_log2(last_offset - first_offset); 99 } 100 101 instanceOop ValueKlass::allocate_instance(TRAPS) { 102 int size = size_helper(); // Query before forming handle. 103 104 instanceOop oop = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 105 assert(oop->mark()->is_always_locked(), "Unlocked value type"); 106 return oop; 107 } 108 109 bool ValueKlass::is_atomic() { 110 return (nonstatic_field_size() * heapOopSize) <= longSize; 111 } 112 113 int ValueKlass::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 // Arrays of... 126 127 bool ValueKlass::flatten_array() { 128 if (!ValueArrayFlatten) { 129 return false; 130 } 131 132 int elem_bytes = raw_value_byte_size(); 133 // Too big 134 if ((ValueArrayElemMaxFlatSize >= 0) && (elem_bytes > ValueArrayElemMaxFlatSize)) { 135 return false; 136 } 137 // Too many embedded oops 138 if ((ValueArrayElemMaxFlatOops >= 0) && (nonstatic_oop_count() > ValueArrayElemMaxFlatOops)) { 139 return false; 140 } 141 142 return true; 143 } 144 145 146 Klass* ValueKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, int n, TRAPS) { 147 if (storage_props.is_null_free()) { 148 return value_array_klass(storage_props, or_null, n, THREAD); 149 } else { 150 return InstanceKlass::array_klass_impl(storage_props, or_null, n, THREAD); 151 } 152 } 153 154 Klass* ValueKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, TRAPS) { 155 return array_klass_impl(storage_props, or_null, 1, THREAD); 156 } 157 158 Klass* ValueKlass::value_array_klass(ArrayStorageProperties storage_props, bool or_null, int rank, TRAPS) { 159 Klass* vak = acquire_value_array_klass(); 160 if (vak == NULL) { 161 if (or_null) return NULL; 162 ResourceMark rm; 163 { 164 // Atomic creation of array_klasses 165 MutexLocker ma(MultiArray_lock, THREAD); 166 if (get_value_array_klass() == NULL) { 167 vak = allocate_value_array_klass(CHECK_NULL); 168 OrderAccess::release_store((Klass**)adr_value_array_klass(), vak); 169 } 170 } 171 } 172 if (!vak->is_valueArray_klass()) { 173 storage_props.clear_flattened(); 174 } 175 if (or_null) { 176 return vak->array_klass_or_null(storage_props, rank); 177 } 178 return vak->array_klass(storage_props, rank, THREAD); 179 } 180 181 Klass* ValueKlass::allocate_value_array_klass(TRAPS) { 182 if (flatten_array() && (is_atomic() || (!ValueArrayAtomicAccess))) { 183 return ValueArrayKlass::allocate_klass(ArrayStorageProperties::flattened_and_null_free, this, THREAD); 184 } 185 return ObjArrayKlass::allocate_objArray_klass(ArrayStorageProperties::null_free, 1, this, THREAD); 186 } 187 188 void ValueKlass::array_klasses_do(void f(Klass* k)) { 189 InstanceKlass::array_klasses_do(f); 190 if (get_value_array_klass() != NULL) 191 ArrayKlass::cast(get_value_array_klass())->array_klasses_do(f); 192 } 193 194 void ValueKlass::raw_field_copy(void* src, void* dst, size_t raw_byte_size) { 195 /* 196 * Try not to shear fields even if not an atomic store... 197 * 198 * First 3 cases handle value array store, otherwise works on the same basis 199 * as JVM_Clone, at this size data is aligned. The order of primitive types 200 * is largest to smallest, and it not possible for fields to stradle long 201 * copy boundaries. 202 * 203 * If MT without exclusive access, possible to observe partial value store, 204 * but not partial primitive and reference field values 205 */ 206 switch (raw_byte_size) { 207 case 1: 208 *((jbyte*) dst) = *(jbyte*)src; 209 break; 210 case 2: 211 *((jshort*) dst) = *(jshort*)src; 212 break; 213 case 4: 214 *((jint*) dst) = *(jint*) src; 215 break; 216 default: 217 assert(raw_byte_size % sizeof(jlong) == 0, "Unaligned raw_byte_size"); 218 Copy::conjoint_jlongs_atomic((jlong*)src, (jlong*)dst, raw_byte_size >> LogBytesPerLong); 219 } 220 } 221 222 /* 223 * Store the value of this klass contained with src into dst. 224 * 225 * This operation is appropriate for use from vastore, vaload and putfield (for values) 226 * 227 * GC barriers currently can lock with no safepoint check and allocate c-heap, 228 * so raw point is "safe" for now. 229 * 230 * Going forward, look to use machine generated (stub gen or bc) version for most used klass layouts 231 * 232 */ 233 void ValueKlass::value_store(void* src, void* dst, size_t raw_byte_size, bool dst_heap, bool dst_uninitialized) { 234 if (contains_oops()) { 235 if (dst_heap) { 236 // src/dst aren't oops, need offset to adjust oop map offset 237 const address dst_oop_addr = ((address) dst) - first_field_offset(); 238 239 ModRefBarrierSet* bs = barrier_set_cast<ModRefBarrierSet>(BarrierSet::barrier_set()); 240 241 // Pre-barriers... 242 OopMapBlock* map = start_of_nonstatic_oop_maps(); 243 OopMapBlock* const end = map + nonstatic_oop_map_count(); 244 while (map != end) { 245 // Shame we can't just use the existing oop iterator...src/dst aren't oop 246 address doop_address = dst_oop_addr + map->offset(); 247 // TEMP HACK: barrier code need to migrate to => access API (need own versions of value type ops) 248 if (UseCompressedOops) { 249 bs->write_ref_array_pre((narrowOop*) doop_address, map->count(), dst_uninitialized); 250 } else { 251 bs->write_ref_array_pre((oop*) doop_address, map->count(), dst_uninitialized); 252 } 253 map++; 254 } 255 256 raw_field_copy(src, dst, raw_byte_size); 257 258 // Post-barriers... 259 map = start_of_nonstatic_oop_maps(); 260 while (map != end) { 261 address doop_address = dst_oop_addr + map->offset(); 262 bs->write_ref_array((HeapWord*) doop_address, map->count()); 263 map++; 264 } 265 } else { // Buffered value case 266 raw_field_copy(src, dst, raw_byte_size); 267 } 268 } else { // Primitive-only case... 269 raw_field_copy(src, dst, raw_byte_size); 270 } 271 } 272 273 // Value type arguments are not passed by reference, instead each 274 // field of the value type is passed as an argument. This helper 275 // function collects the fields of the value types (including embedded 276 // value type's fields) in a list. Included with the field's type is 277 // the offset of each field in the value type: i2c and c2i adapters 278 // need that to load or store fields. Finally, the list of fields is 279 // sorted in order of increasing offsets: the adapters and the 280 // compiled code need to agree upon the order of fields. 281 // 282 // The list of basic types that is returned starts with a T_VALUETYPE 283 // and ends with an extra T_VOID. T_VALUETYPE/T_VOID pairs are used as 284 // delimiters. Every entry between the two is a field of the value 285 // type. If there's an embedded value type in the list, it also starts 286 // with a T_VALUETYPE and ends with a T_VOID. This is so we can 287 // generate a unique fingerprint for the method's adapters and we can 288 // generate the list of basic types from the interpreter point of view 289 // (value types passed as reference: iterate on the list until a 290 // T_VALUETYPE, drop everything until and including the closing 291 // T_VOID) or the compiler point of view (each field of the value 292 // types is an argument: drop all T_VALUETYPE/T_VOID from the list). 293 int ValueKlass::collect_fields(GrowableArray<SigEntry>* sig, int base_off) const { 294 int count = 0; 295 SigEntry::add_entry(sig, T_VALUETYPE, base_off); 296 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 297 if (fs.access_flags().is_static()) continue; 298 int offset = base_off + fs.offset() - (base_off > 0 ? first_field_offset() : 0); 299 if (fs.is_flattened()) { 300 // Resolve klass of flattened value type field and recursively collect fields 301 Klass* vk = get_value_field_klass(fs.index()); 302 count += ValueKlass::cast(vk)->collect_fields(sig, offset); 303 } else { 304 BasicType bt = FieldType::basic_type(fs.signature()); 305 if (bt == T_VALUETYPE) { 306 bt = T_OBJECT; 307 } 308 SigEntry::add_entry(sig, bt, offset); 309 count += type2size[bt]; 310 } 311 } 312 int offset = base_off + size_helper()*HeapWordSize - (base_off > 0 ? first_field_offset() : 0); 313 SigEntry::add_entry(sig, T_VOID, offset); 314 if (base_off == 0) { 315 sig->sort(SigEntry::compare); 316 } 317 assert(sig->at(0)._bt == T_VALUETYPE && sig->at(sig->length()-1)._bt == T_VOID, "broken structure"); 318 return count; 319 } 320 321 void ValueKlass::initialize_calling_convention(TRAPS) { 322 // Because the pack and unpack handler addresses need to be loadable from generated code, 323 // they are stored at a fixed offset in the klass metadata. Since value type klasses do 324 // not have a vtable, the vtable offset is used to store these addresses. 325 if (ValueTypeReturnedAsFields || ValueTypePassFieldsAsArgs) { 326 ResourceMark rm; 327 GrowableArray<SigEntry> sig_vk; 328 int nb_fields = collect_fields(&sig_vk); 329 Array<SigEntry>* extended_sig = MetadataFactory::new_array<SigEntry>(class_loader_data(), sig_vk.length(), CHECK); 330 *((Array<SigEntry>**)adr_extended_sig()) = extended_sig; 331 for (int i = 0; i < sig_vk.length(); i++) { 332 extended_sig->at_put(i, sig_vk.at(i)); 333 } 334 335 if (ValueTypeReturnedAsFields) { 336 nb_fields++; 337 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, nb_fields); 338 sig_bt[0] = T_METADATA; 339 SigEntry::fill_sig_bt(&sig_vk, sig_bt+1); 340 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, nb_fields); 341 int total = SharedRuntime::java_return_convention(sig_bt, regs, nb_fields); 342 343 if (total > 0) { 344 Array<VMRegPair>* return_regs = MetadataFactory::new_array<VMRegPair>(class_loader_data(), nb_fields, CHECK); 345 *((Array<VMRegPair>**)adr_return_regs()) = return_regs; 346 for (int i = 0; i < nb_fields; i++) { 347 return_regs->at_put(i, regs[i]); 348 } 349 350 BufferedValueTypeBlob* buffered_blob = SharedRuntime::generate_buffered_value_type_adapter(this); 351 *((address*)adr_pack_handler()) = buffered_blob->pack_fields(); 352 *((address*)adr_unpack_handler()) = buffered_blob->unpack_fields(); 353 assert(CodeCache::find_blob(pack_handler()) == buffered_blob, "lost track of blob"); 354 } 355 } 356 } 357 } 358 359 void ValueKlass::deallocate_contents(ClassLoaderData* loader_data) { 360 if (extended_sig() != NULL) { 361 MetadataFactory::free_array<SigEntry>(loader_data, extended_sig()); 362 } 363 if (return_regs() != NULL) { 364 MetadataFactory::free_array<VMRegPair>(loader_data, return_regs()); 365 } 366 cleanup_blobs(); 367 InstanceKlass::deallocate_contents(loader_data); 368 } 369 370 void ValueKlass::cleanup(ValueKlass* ik) { 371 ik->cleanup_blobs(); 372 } 373 374 void ValueKlass::cleanup_blobs() { 375 if (pack_handler() != NULL) { 376 CodeBlob* buffered_blob = CodeCache::find_blob(pack_handler()); 377 assert(buffered_blob->is_buffered_value_type_blob(), "bad blob type"); 378 BufferBlob::free((BufferBlob*)buffered_blob); 379 *((address*)adr_pack_handler()) = NULL; 380 *((address*)adr_unpack_handler()) = NULL; 381 } 382 } 383 384 // Can this value type be returned as multiple values? 385 bool ValueKlass::can_be_returned_as_fields() const { 386 return return_regs() != NULL; 387 } 388 389 // Create handles for all oop fields returned in registers that are going to be live across a safepoint 390 void ValueKlass::save_oop_fields(const RegisterMap& reg_map, GrowableArray<Handle>& handles) const { 391 Thread* thread = Thread::current(); 392 const Array<SigEntry>* sig_vk = extended_sig(); 393 const Array<VMRegPair>* regs = return_regs(); 394 int j = 1; 395 396 for (int i = 0; i < sig_vk->length(); i++) { 397 BasicType bt = sig_vk->at(i)._bt; 398 if (bt == T_OBJECT || bt == T_ARRAY) { 399 VMRegPair pair = regs->at(j); 400 address loc = reg_map.location(pair.first()); 401 oop v = *(oop*)loc; 402 assert(v == NULL || oopDesc::is_oop(v), "not an oop?"); 403 assert(Universe::heap()->is_in_or_null(v), "must be heap pointer"); 404 handles.push(Handle(thread, v)); 405 } 406 if (bt == T_VALUETYPE) { 407 continue; 408 } 409 if (bt == T_VOID && 410 sig_vk->at(i-1)._bt != T_LONG && 411 sig_vk->at(i-1)._bt != T_DOUBLE) { 412 continue; 413 } 414 j++; 415 } 416 assert(j == regs->length(), "missed a field?"); 417 } 418 419 // Update oop fields in registers from handles after a safepoint 420 void ValueKlass::restore_oop_results(RegisterMap& reg_map, GrowableArray<Handle>& handles) const { 421 assert(ValueTypeReturnedAsFields, "inconsistent"); 422 const Array<SigEntry>* sig_vk = extended_sig(); 423 const Array<VMRegPair>* regs = return_regs(); 424 assert(regs != NULL, "inconsistent"); 425 426 int j = 1; 427 for (int i = 0, k = 0; i < sig_vk->length(); i++) { 428 BasicType bt = sig_vk->at(i)._bt; 429 if (bt == T_OBJECT || bt == T_ARRAY) { 430 VMRegPair pair = regs->at(j); 431 address loc = reg_map.location(pair.first()); 432 *(oop*)loc = handles.at(k++)(); 433 } 434 if (bt == T_VALUETYPE) { 435 continue; 436 } 437 if (bt == T_VOID && 438 sig_vk->at(i-1)._bt != T_LONG && 439 sig_vk->at(i-1)._bt != T_DOUBLE) { 440 continue; 441 } 442 j++; 443 } 444 assert(j == regs->length(), "missed a field?"); 445 } 446 447 // Fields are in registers. Create an instance of the value type and 448 // initialize it with the values of the fields. 449 oop ValueKlass::realloc_result(const RegisterMap& reg_map, const GrowableArray<Handle>& handles, TRAPS) { 450 oop new_vt = allocate_instance(CHECK_NULL); 451 const Array<SigEntry>* sig_vk = extended_sig(); 452 const Array<VMRegPair>* regs = return_regs(); 453 454 int j = 1; 455 int k = 0; 456 for (int i = 0; i < sig_vk->length(); i++) { 457 BasicType bt = sig_vk->at(i)._bt; 458 if (bt == T_VALUETYPE) { 459 continue; 460 } 461 if (bt == T_VOID) { 462 if (sig_vk->at(i-1)._bt == T_LONG || 463 sig_vk->at(i-1)._bt == T_DOUBLE) { 464 j++; 465 } 466 continue; 467 } 468 int off = sig_vk->at(i)._offset; 469 assert(off > 0, "offset in object should be positive"); 470 VMRegPair pair = regs->at(j); 471 address loc = reg_map.location(pair.first()); 472 switch(bt) { 473 case T_BOOLEAN: { 474 new_vt->bool_field_put(off, *(jboolean*)loc); 475 break; 476 } 477 case T_CHAR: { 478 new_vt->char_field_put(off, *(jchar*)loc); 479 break; 480 } 481 case T_BYTE: { 482 new_vt->byte_field_put(off, *(jbyte*)loc); 483 break; 484 } 485 case T_SHORT: { 486 new_vt->short_field_put(off, *(jshort*)loc); 487 break; 488 } 489 case T_INT: { 490 new_vt->int_field_put(off, *(jint*)loc); 491 break; 492 } 493 case T_LONG: { 494 #ifdef _LP64 495 new_vt->double_field_put(off, *(jdouble*)loc); 496 #else 497 Unimplemented(); 498 #endif 499 break; 500 } 501 case T_OBJECT: 502 case T_ARRAY: { 503 Handle handle = handles.at(k++); 504 new_vt->obj_field_put(off, handle()); 505 break; 506 } 507 case T_FLOAT: { 508 new_vt->float_field_put(off, *(jfloat*)loc); 509 break; 510 } 511 case T_DOUBLE: { 512 new_vt->double_field_put(off, *(jdouble*)loc); 513 break; 514 } 515 default: 516 ShouldNotReachHere(); 517 } 518 *(intptr_t*)loc = 0xDEAD; 519 j++; 520 } 521 assert(j == regs->length(), "missed a field?"); 522 assert(k == handles.length(), "missed an oop?"); 523 return new_vt; 524 } 525 526 // Check the return register for a ValueKlass oop 527 ValueKlass* ValueKlass::returned_value_klass(const RegisterMap& map) { 528 BasicType bt = T_METADATA; 529 VMRegPair pair; 530 int nb = SharedRuntime::java_return_convention(&bt, &pair, 1); 531 assert(nb == 1, "broken"); 532 533 address loc = map.location(pair.first()); 534 intptr_t ptr = *(intptr_t*)loc; 535 if (is_set_nth_bit(ptr, 0)) { 536 // Oop is tagged, must be a ValueKlass oop 537 clear_nth_bit(ptr, 0); 538 assert(Metaspace::contains((void*)ptr), "should be klass"); 539 ValueKlass* vk = (ValueKlass*)ptr; 540 assert(vk->can_be_returned_as_fields(), "must be able to return as fields"); 541 return vk; 542 } 543 #ifdef ASSERT 544 // Oop is not tagged, must be a valid oop 545 if (VerifyOops) { 546 oopDesc::verify(oop((HeapWord*)ptr)); 547 } 548 #endif 549 return NULL; 550 } 551 552 void ValueKlass::verify_on(outputStream* st) { 553 InstanceKlass::verify_on(st); 554 guarantee(prototype_header()->is_always_locked(), "Prototype header is not always locked"); 555 } 556 557 void ValueKlass::oop_verify_on(oop obj, outputStream* st) { 558 InstanceKlass::oop_verify_on(obj, st); 559 guarantee(obj->mark()->is_always_locked(), "Header is not always locked"); 560 }