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