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/moduleEntry.hpp"
27 #include "classfile/packageEntry.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "memory/iterator.inline.hpp"
33 #include "memory/metadataFactory.hpp"
34 #include "memory/metaspaceClosure.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "memory/universe.hpp"
38 #include "oops/arrayKlass.inline.hpp"
39 #include "oops/arrayOop.hpp"
40 #include "oops/flatArrayOop.hpp"
41 #include "oops/flatArrayOop.inline.hpp"
42 #include "oops/inlineKlass.hpp"
43 #include "oops/instanceKlass.hpp"
44 #include "oops/klass.inline.hpp"
45 #include "oops/objArrayKlass.hpp"
46 #include "oops/objArrayOop.inline.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/verifyOopClosure.hpp"
49 #include "runtime/handles.inline.hpp"
50 #include "runtime/mutexLocker.hpp"
51 #include "utilities/copy.hpp"
52 #include "utilities/macros.hpp"
53
54 #include "oops/flatArrayKlass.hpp"
55
56 // Allocation...
57
58 FlatArrayKlass::FlatArrayKlass(Klass* element_klass, Symbol* name) : ArrayKlass(name, Kind) {
59 assert(element_klass->is_inline_klass(), "Expected Inline");
60
61 set_element_klass(InlineKlass::cast(element_klass));
62 set_class_loader_data(element_klass->class_loader_data());
63
64 set_layout_helper(array_layout_helper(InlineKlass::cast(element_klass)));
65 assert(is_array_klass(), "sanity");
66 assert(is_flatArray_klass(), "sanity");
67 assert(is_null_free_array_klass(), "sanity");
68
69 #ifdef _LP64
70 set_prototype_header(markWord::flat_array_prototype());
71 assert(prototype_header().is_flat_array(), "sanity");
72 #else
73 set_prototype_header(markWord::inline_type_prototype());
74 #endif
75
76 #ifndef PRODUCT
77 if (PrintFlatArrayLayout) {
78 print();
79 }
80 #endif
81 }
82
83 InlineKlass* FlatArrayKlass::element_klass() const {
84 return InlineKlass::cast(_element_klass);
85 }
86
87 void FlatArrayKlass::set_element_klass(Klass* k) {
88 _element_klass = k;
89 }
90
91 FlatArrayKlass* FlatArrayKlass::allocate_klass(Klass* eklass, TRAPS) {
92 guarantee((!Universe::is_bootstrapping() || vmClasses::Object_klass_loaded()), "Really ?!");
93 assert(UseFlatArray, "Flatten array required");
94
95 InlineKlass* element_klass = InlineKlass::cast(eklass);
96 assert(element_klass->is_naturally_atomic() || (!InlineArrayAtomicAccess), "Atomic by-default");
97
98 /*
99 * MVT->LWorld, now need to allocate secondaries array types, just like objArrayKlass...
100 * ...so now we are trying out covariant array types, just copy objArrayKlass
101 * TODO refactor any remaining commonality
102 *
103 */
104 // Eagerly allocate the direct array supertype.
105 Klass* super_klass = NULL;
106 Klass* element_super = element_klass->super();
107 if (element_super != NULL) {
108 // The element type has a direct super. E.g., String[] has direct super of Object[].
109 super_klass = element_klass->array_klass_or_null();
110 bool supers_exist = super_klass != NULL;
111 // Also, see if the element has secondary supertypes.
112 // We need an array type for each.
113 const Array<Klass*>* element_supers = element_klass->secondary_supers();
114 for( int i = element_supers->length()-1; i >= 0; i-- ) {
115 Klass* elem_super = element_supers->at(i);
116 if (elem_super->array_klass_or_null() == NULL) {
117 supers_exist = false;
118 break;
119 }
120 }
121 if (!supers_exist) {
122 // Oops. Not allocated yet. Back out, allocate it, and retry.
123 Klass* ek = NULL;
124 {
125 MutexUnlocker mu(MultiArray_lock);
126 super_klass = element_klass->array_klass(CHECK_NULL);
127 for( int i = element_supers->length()-1; i >= 0; i-- ) {
128 Klass* elem_super = element_supers->at(i);
129 elem_super->array_klass(CHECK_NULL);
130 }
131 // Now retry from the beginning
132 ek = element_klass->value_array_klass(CHECK_NULL);
133 } // re-lock
134 return FlatArrayKlass::cast(ek);
135 }
136 }
137
138 Symbol* name = ArrayKlass::create_element_klass_array_name(element_klass, true, CHECK_NULL);
139 ClassLoaderData* loader_data = element_klass->class_loader_data();
140 int size = ArrayKlass::static_size(FlatArrayKlass::header_size());
141 FlatArrayKlass* vak = new (loader_data, size, THREAD) FlatArrayKlass(element_klass, name);
142
143 ModuleEntry* module = vak->module();
144 assert(module != NULL, "No module entry for array");
145 complete_create_array_klass(vak, super_klass, module, CHECK_NULL);
146
147 loader_data->add_class(vak);
148
149 return vak;
150 }
151
152 void FlatArrayKlass::initialize(TRAPS) {
153 element_klass()->initialize(THREAD);
154 }
155
156 void FlatArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) {
157 ArrayKlass::metaspace_pointers_do(it);
158 it->push(&_element_klass);
159 }
160
161 // Oops allocation...
162 flatArrayOop FlatArrayKlass::allocate(int length, TRAPS) {
163 check_array_allocation_length(length, max_elements(), CHECK_NULL);
164 int size = flatArrayOopDesc::object_size(layout_helper(), length);
165 return (flatArrayOop) Universe::heap()->array_allocate(this, size, length, true, THREAD);
166 }
167
168
169 oop FlatArrayKlass::multi_allocate(int rank, jint* last_size, TRAPS) {
170 // For flatArrays this is only called for the last dimension
171 assert(rank == 1, "just checking");
172 int length = *last_size;
173 return allocate(length, THREAD);
174 }
175
176 jint FlatArrayKlass::array_layout_helper(InlineKlass* vk) {
177 BasicType etype = T_PRIMITIVE_OBJECT;
178 int esize = log2i_exact(round_up_power_of_2(vk->get_exact_size_in_bytes()));
179 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
180
181 int lh = Klass::array_layout_helper(_lh_array_tag_vt_value, true, hsize, etype, esize);
182
183 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
184 assert(layout_helper_is_array(lh), "correct kind");
185 assert(layout_helper_is_flatArray(lh), "correct kind");
186 assert(!layout_helper_is_typeArray(lh), "correct kind");
187 assert(!layout_helper_is_objArray(lh), "correct kind");
188 assert(layout_helper_is_null_free(lh), "correct kind");
189 assert(layout_helper_header_size(lh) == hsize, "correct decode");
190 assert(layout_helper_element_type(lh) == etype, "correct decode");
191 assert(layout_helper_log2_element_size(lh) == esize, "correct decode");
192 assert((1 << esize) < BytesPerLong || is_aligned(hsize, HeapWordsPerLong), "unaligned base");
193
194 return lh;
195 }
196
197 size_t FlatArrayKlass::oop_size(oop obj) const {
198 assert(obj->klass()->is_flatArray_klass(),"must be an flat array");
199 flatArrayOop array = flatArrayOop(obj);
200 return array->object_size();
201 }
202
203 // For now return the maximum number of array elements that will not exceed:
204 // nof bytes = "max_jint * HeapWord" since the "oopDesc::oop_iterate_size"
205 // returns "int" HeapWords, need fix for JDK-4718400 and JDK-8233189
206 jint FlatArrayKlass::max_elements() const {
207 // Check the max number of heap words limit first (because of int32_t in oopDesc_oop_size() etc)
208 size_t max_size = max_jint;
209 max_size -= arrayOopDesc::header_size(T_PRIMITIVE_OBJECT);
210 max_size = align_down(max_size, MinObjAlignment);
211 max_size <<= LogHeapWordSize; // convert to max payload size in bytes
212 max_size >>= layout_helper_log2_element_size(_layout_helper); // divide by element size (in bytes) = max elements
213 // Within int32_t heap words, still can't exceed Java array element limit
214 if (max_size > max_jint) {
215 max_size = max_jint;
216 }
217 assert((max_size >> LogHeapWordSize) <= max_jint, "Overflow");
218 return (jint) max_size;
219 }
220
221 oop FlatArrayKlass::protection_domain() const {
222 return element_klass()->protection_domain();
223 }
224
225 // Temp hack having this here: need to move towards Access API
226 static bool needs_backwards_copy(arrayOop s, int src_pos,
227 arrayOop d, int dst_pos, int length) {
228 return (s == d) && (dst_pos > src_pos) && (dst_pos - src_pos) < length;
229 }
230
231 void FlatArrayKlass::copy_array(arrayOop s, int src_pos,
232 arrayOop d, int dst_pos, int length, TRAPS) {
233
234 assert(s->is_objArray() || s->is_flatArray(), "must be obj or flat array");
235
236 // Check destination
237 if ((!d->is_flatArray()) && (!d->is_objArray())) {
238 THROW(vmSymbols::java_lang_ArrayStoreException());
239 }
240
241 // Check if all offsets and lengths are non negative
242 if (src_pos < 0 || dst_pos < 0 || length < 0) {
243 THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException());
244 }
245 // Check if the ranges are valid
246 if ( (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length())
247 || (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length()) ) {
248 THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException());
249 }
250 // Check zero copy
251 if (length == 0)
252 return;
253
254 ArrayKlass* sk = ArrayKlass::cast(s->klass());
255 ArrayKlass* dk = ArrayKlass::cast(d->klass());
256 Klass* d_elem_klass = dk->element_klass();
257 Klass* s_elem_klass = sk->element_klass();
258 /**** CMH: compare and contrast impl, re-factor once we find edge cases... ****/
259
260 if (sk->is_flatArray_klass()) {
261 assert(sk == this, "Unexpected call to copy_array");
262 // Check subtype, all src homogeneous, so just once
263 if (!s_elem_klass->is_subtype_of(d_elem_klass)) {
264 THROW(vmSymbols::java_lang_ArrayStoreException());
265 }
266
267 flatArrayOop sa = flatArrayOop(s);
268 InlineKlass* s_elem_vklass = element_klass();
269
270 // flatArray-to-flatArray
271 if (dk->is_flatArray_klass()) {
272 // element types MUST be exact, subtype check would be dangerous
273 if (dk != this) {
274 THROW(vmSymbols::java_lang_ArrayStoreException());
275 }
276
277 flatArrayOop da = flatArrayOop(d);
278 address dst = (address) da->value_at_addr(dst_pos, layout_helper());
279 address src = (address) sa->value_at_addr(src_pos, layout_helper());
280 if (contains_oops()) {
281 int elem_incr = 1 << log2_element_size();
282 address src_end = src + (length << log2_element_size());
283 if (needs_backwards_copy(s, src_pos, d, dst_pos, length)) {
284 swap(src, src_end);
285 dst = dst + (length << log2_element_size());
286 do {
287 src -= elem_incr;
288 dst -= elem_incr;
289 HeapAccess<>::value_copy(src, dst, s_elem_vklass);
290 } while (src > src_end);
291 } else {
292 address src_end = src + (length << log2_element_size());
293 while (src < src_end) {
294 HeapAccess<>::value_copy(src, dst, s_elem_vklass);
295 src += elem_incr;
296 dst += elem_incr;
297 }
298 }
299 } else {
300 // we are basically a type array...don't bother limiting element copy
301 // it would have to be a lot wasted space to be worth value_store() calls, need a setting here ?
302 Copy::conjoint_memory_atomic(src, dst, (size_t)length << log2_element_size());
303 }
304 }
305 else { // flatArray-to-objArray
306 assert(dk->is_objArray_klass(), "Expected objArray here");
307 // Need to allocate each new src elem payload -> dst oop
308 objArrayHandle dh(THREAD, (objArrayOop)d);
309 flatArrayHandle sh(THREAD, sa);
310 int dst_end = dst_pos + length;
311 while (dst_pos < dst_end) {
312 oop o = flatArrayOopDesc::value_alloc_copy_from_index(sh, src_pos, CHECK);
313 dh->obj_at_put(dst_pos, o);
314 dst_pos++;
315 src_pos++;
316 }
317 }
318 } else {
319 assert(s->is_objArray(), "Expected objArray");
320 objArrayOop sa = objArrayOop(s);
321 assert(d->is_flatArray(), "Excepted flatArray"); // objArray-to-flatArray
322 InlineKlass* d_elem_vklass = InlineKlass::cast(d_elem_klass);
323 flatArrayOop da = flatArrayOop(d);
324
325 int src_end = src_pos + length;
326 int delem_incr = 1 << dk->log2_element_size();
327 address dst = (address) da->value_at_addr(dst_pos, layout_helper());
328 while (src_pos < src_end) {
329 oop se = sa->obj_at(src_pos);
330 if (se == NULL) {
331 THROW(vmSymbols::java_lang_NullPointerException());
332 }
333 // Check exact type per element
334 if (se->klass() != d_elem_klass) {
335 THROW(vmSymbols::java_lang_ArrayStoreException());
336 }
337 d_elem_vklass->inline_copy_oop_to_payload(se, dst);
338 dst += delem_incr;
339 src_pos++;
340 }
341 }
342 }
343
344
345 Klass* FlatArrayKlass::array_klass(int n, TRAPS) {
346 assert(dimension() <= n, "check order of chain");
347 int dim = dimension();
348 if (dim == n) return this;
349
350 // lock-free read needs acquire semantics
351 if (higher_dimension_acquire() == NULL) {
352
353 ResourceMark rm(THREAD);
354 {
355 // Ensure atomic creation of higher dimensions
356 MutexLocker mu(THREAD, MultiArray_lock);
357
358 // Check if another thread beat us
359 if (higher_dimension() == NULL) {
360
361 // Create multi-dim klass object and link them together
362 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, false, true, CHECK_NULL);
363 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
364 ak->set_lower_dimension(this);
365 // use 'release' to pair with lock-free load
366 release_set_higher_dimension(ak);
367 assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass");
368 }
369 }
370 }
371
372 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension());
373 JavaThread::cast(THREAD)->check_possible_safepoint();
374 return ak->array_klass(n, THREAD);
375 }
376
377 Klass* FlatArrayKlass::array_klass_or_null(int n) {
378
379 assert(dimension() <= n, "check order of chain");
380 int dim = dimension();
381 if (dim == n) return this;
382
383 // lock-free read needs acquire semantics
384 if (higher_dimension_acquire() == NULL) {
385 return NULL;
386 }
387
388 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension());
389 return ak->array_klass_or_null(n);
390 }
391
392 Klass* FlatArrayKlass::array_klass(TRAPS) {
393 return array_klass(dimension() + 1, THREAD);
394 }
395
396 Klass* FlatArrayKlass::array_klass_or_null() {
397 return array_klass_or_null(dimension() + 1);
398 }
399
400
401 ModuleEntry* FlatArrayKlass::module() const {
402 assert(element_klass() != NULL, "FlatArrayKlass returned unexpected NULL bottom_klass");
403 // The array is defined in the module of its bottom class
404 return element_klass()->module();
405 }
406
407 PackageEntry* FlatArrayKlass::package() const {
408 assert(element_klass() != NULL, "FlatArrayKlass returned unexpected NULL bottom_klass");
409 return element_klass()->package();
410 }
411
412 bool FlatArrayKlass::can_be_primary_super_slow() const {
413 return true;
414 }
415
416 GrowableArray<Klass*>* FlatArrayKlass::compute_secondary_supers(int num_extra_slots,
417 Array<InstanceKlass*>* transitive_interfaces) {
418 assert(transitive_interfaces == NULL, "sanity");
419 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... };
420 Array<Klass*>* elem_supers = element_klass()->secondary_supers();
421 int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length();
422 int num_secondaries = num_extra_slots + 2 + num_elem_supers;
423 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2);
424
425 secondaries->push(vmClasses::Cloneable_klass());
426 secondaries->push(vmClasses::Serializable_klass());
427 for (int i = 0; i < num_elem_supers; i++) {
428 Klass* elem_super = (Klass*) elem_supers->at(i);
429 Klass* array_super = elem_super->array_klass_or_null();
430 assert(array_super != NULL, "must already have been created");
431 secondaries->push(array_super);
432 }
433 return secondaries;
434 }
435
436 jint FlatArrayKlass::compute_modifier_flags() const {
437 // The modifier for an flatArray is the same as its element
438 jint element_flags = element_klass()->compute_modifier_flags();
439
440 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED))
441 | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL);
442 }
443
444 void FlatArrayKlass::print_on(outputStream* st) const {
445 #ifndef PRODUCT
446 assert(!is_objArray_klass(), "Unimplemented");
447
448 st->print("Flat Type Array: ");
449 Klass::print_on(st);
450
451 st->print(" - element klass: ");
452 element_klass()->print_value_on(st);
453 st->cr();
454
455 int elem_size = element_byte_size();
456 st->print(" - element size %i ", elem_size);
457 st->print("aligned layout size %i", 1 << layout_helper_log2_element_size(layout_helper()));
458 st->cr();
459 #endif //PRODUCT
460 }
461
462 void FlatArrayKlass::print_value_on(outputStream* st) const {
463 assert(is_klass(), "must be klass");
464
465 element_klass()->print_value_on(st);
466 st->print("[]");
467 }
468
469
470 #ifndef PRODUCT
471 void FlatArrayKlass::oop_print_on(oop obj, outputStream* st) {
472 ArrayKlass::oop_print_on(obj, st);
473 flatArrayOop va = flatArrayOop(obj);
474 InlineKlass* vk = element_klass();
475 int print_len = MIN2((intx) va->length(), MaxElementPrintSize);
476 for(int index = 0; index < print_len; index++) {
477 int off = (address) va->value_at_addr(index, layout_helper()) - cast_from_oop<address>(obj);
478 st->print_cr(" - Index %3d offset %3d: ", index, off);
479 oop obj = cast_to_oop((address)va->value_at_addr(index, layout_helper()) - vk->first_field_offset());
480 FieldPrinter print_field(st, obj);
481 vk->do_nonstatic_fields(&print_field);
482 st->cr();
483 }
484 int remaining = va->length() - print_len;
485 if (remaining > 0) {
486 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining);
487 }
488 }
489 #endif //PRODUCT
490
491 void FlatArrayKlass::oop_print_value_on(oop obj, outputStream* st) {
492 assert(obj->is_flatArray(), "must be flatArray");
493 st->print("a ");
494 element_klass()->print_value_on(st);
495 int len = flatArrayOop(obj)->length();
496 st->print("[%d] ", len);
497 obj->print_address_on(st);
498 if (PrintMiscellaneous && (WizardMode || Verbose)) {
499 int lh = layout_helper();
500 st->print("{");
501 for (int i = 0; i < len; i++) {
502 if (i > 4) {
503 st->print("..."); break;
504 }
505 st->print(" " INTPTR_FORMAT, (intptr_t)(void*)flatArrayOop(obj)->value_at_addr(i , lh));
506 }
507 st->print(" }");
508 }
509 }
510
511 // Verification
512 class VerifyElementClosure: public BasicOopIterateClosure {
513 public:
514 virtual void do_oop(oop* p) { VerifyOopClosure::verify_oop.do_oop(p); }
515 virtual void do_oop(narrowOop* p) { VerifyOopClosure::verify_oop.do_oop(p); }
516 };
517
518 void FlatArrayKlass::oop_verify_on(oop obj, outputStream* st) {
519 ArrayKlass::oop_verify_on(obj, st);
520 guarantee(obj->is_flatArray(), "must be flatArray");
521
522 if (contains_oops()) {
523 flatArrayOop va = flatArrayOop(obj);
524 VerifyElementClosure ec;
525 va->oop_iterate(&ec);
526 }
527 }
528
529 void FlatArrayKlass::verify_on(outputStream* st) {
530 ArrayKlass::verify_on(st);
531 guarantee(element_klass()->is_inline_klass(), "should be inline type klass");
532 }