1 /*
2 * Copyright (c) 1998, 2025, 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 "code/codeBlob.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/nmethod.hpp"
28 #include "code/scopeDesc.hpp"
29 #include "compiler/oopMap.inline.hpp"
30 #include "gc/shared/collectedHeap.hpp"
31 #include "logging/log.hpp"
32 #include "logging/logStream.hpp"
33 #include "memory/allocation.inline.hpp"
34 #include "memory/iterator.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "oops/compressedOops.hpp"
37 #include "runtime/atomic.hpp"
38 #include "runtime/frame.inline.hpp"
39 #include "runtime/handles.inline.hpp"
40 #include "runtime/signature.hpp"
41 #include "runtime/stackWatermarkSet.inline.hpp"
42 #include "utilities/align.hpp"
43 #include "utilities/lockFreeStack.hpp"
44 #ifdef COMPILER1
45 #include "c1/c1_Defs.hpp"
46 #endif
47 #ifdef COMPILER2
48 #include "opto/optoreg.hpp"
49 #endif
50 #if INCLUDE_JVMCI
51 #include "jvmci/jvmci_globals.hpp"
52 #endif
53
54 static_assert(sizeof(oop) == sizeof(intptr_t), "Derived pointer sanity check");
55
56 static inline intptr_t derived_pointer_value(derived_pointer p) {
57 return static_cast<intptr_t>(p);
58 }
59
60 static inline derived_pointer to_derived_pointer(intptr_t obj) {
61 return static_cast<derived_pointer>(obj);
62 }
63
64 static inline intptr_t operator-(derived_pointer p, derived_pointer p1) {
65 return derived_pointer_value(p) - derived_pointer_value(p1);
66 }
67
68 static inline derived_pointer operator+(derived_pointer p, intptr_t offset) {
69 return static_cast<derived_pointer>(derived_pointer_value(p) + offset);
70 }
71
72 // OopMapStream
73
74 OopMapStream::OopMapStream(const OopMap* oop_map)
75 : _stream(oop_map->write_stream()->buffer()) {
76 _size = oop_map->omv_count();
77 _position = 0;
78 _valid_omv = false;
79 }
80
81 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map)
82 : _stream(oop_map->data_addr()) {
83 _size = oop_map->count();
84 _position = 0;
85 _valid_omv = false;
86 }
87
88 void OopMapStream::find_next() {
89 if (_position++ < _size) {
90 _omv.read_from(&_stream);
91 _valid_omv = true;
92 return;
93 }
94 _valid_omv = false;
95 }
96
97
98 // OopMap
99
100 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
101 // slots to hold 4-byte values like ints and floats in the LP64 build.
102 OopMap::OopMap(int frame_size, int arg_count) {
103 // OopMaps are usually quite so small, so pick a small initial size
104 set_write_stream(new CompressedWriteStream(32));
105 set_omv_count(0);
106 _num_oops = 0;
107 _has_derived_oops = false;
108 _index = -1;
109
110 #ifdef ASSERT
111 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
112 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
113 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
114 #endif
115 }
116
117
118 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
119 // This constructor does a deep copy
120 // of the source OopMap.
121 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
122 set_omv_count(0);
123 set_offset(source->offset());
124 _num_oops = source->num_oops();
125 _has_derived_oops = source->has_derived_oops();
126 _index = -1;
127
128 #ifdef ASSERT
129 _locs_length = source->_locs_length;
130 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
131 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
132 #endif
133
134 // We need to copy the entries too.
135 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
136 OopMapValue omv = oms.current();
137 omv.write_on(write_stream());
138 increment_count();
139 }
140 }
141
142
143 OopMap* OopMap::deep_copy() {
144 return new OopMap(_deep_copy_token, this);
145 }
146
147 void OopMap::copy_data_to(address addr) const {
148 memcpy(addr, write_stream()->buffer(), write_stream()->position());
149 }
150
151 class OopMapSort {
152 private:
153 const OopMap* _map;
154 OopMapValue* _values;
155 int _count;
156
157 public:
158 OopMapSort(const OopMap* map) : _map(map), _count(0) {
159 _values = NEW_RESOURCE_ARRAY(OopMapValue, _map->omv_count());
160 }
161
162 void sort();
163
164 void print();
165
166 void write(CompressedWriteStream* stream) {
167 for (int i = 0; i < _count; ++i) {
168 _values[i].write_on(stream);
169 }
170 }
171
172 private:
173 int find_derived_position(OopMapValue omv, int start) {
174 assert(omv.type() == OopMapValue::derived_oop_value, "");
175
176 VMReg base = omv.content_reg();
177 int i = start;
178
179 for (; i < _count; ++i) {
180 if (base == _values[i].reg()) {
181
182 for (int n = i + 1; n < _count; ++n) {
183 if (_values[i].type() != OopMapValue::derived_oop_value || _values[i].content_reg() != base) {
184 return n;
185 }
186
187 if (derived_cost(_values[i]) > derived_cost(omv)) {
188 return n;
189 }
190 }
191 return _count;
192 }
193 }
194
195 assert(false, "failed to find base");
196 return -1;
197 }
198
199 int find_position(OopMapValue omv, int start) {
200 assert(omv.type() != OopMapValue::derived_oop_value, "");
201
202 int i = start;
203 for (; i < _count; ++i) {
204 if (omv_cost(_values[i]) > omv_cost(omv)) {
205 return i;
206 }
207 }
208 assert(i < _map->omv_count(), "bounds check");
209 return i;
210 }
211
212 void insert(OopMapValue value, int pos) {
213 assert(pos >= 0 && pos < _map->omv_count(), "bounds check");
214 assert(pos <= _count, "sanity");
215
216 if (pos < _count) {
217 OopMapValue prev = _values[pos];
218
219 for (int i = pos; i < _count; ++i) {
220 OopMapValue tmp = _values[i+1];
221 _values[i+1] = prev;
222 prev = tmp;
223 }
224 }
225 _values[pos] = value;
226
227 ++_count;
228 }
229
230 int omv_cost(OopMapValue omv) {
231 assert(omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value, "");
232 return reg_cost(omv.reg());
233 }
234
235 int reg_cost(VMReg reg) {
236 if (reg->is_reg()) {
237 return 0;
238 }
239 return reg->reg2stack() * VMRegImpl::stack_slot_size;
240 }
241
242 int derived_cost(OopMapValue omv) {
243 return reg_cost(omv.reg());
244 }
245 };
246
247 void OopMapSort::sort() {
248 #ifdef ASSERT
249 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
250 OopMapValue omv = oms.current();
251 assert(omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value ||
252 omv.type() == OopMapValue::derived_oop_value || omv.type() == OopMapValue::callee_saved_value, "");
253 }
254 #endif
255
256 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
257 if (oms.current().type() == OopMapValue::callee_saved_value) {
258 insert(oms.current(), _count);
259 }
260 }
261
262 int start = _count;
263 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
264 OopMapValue omv = oms.current();
265 if (omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value) {
266 int pos = find_position(omv, start);
267 insert(omv, pos);
268 }
269 }
270
271 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
272 OopMapValue omv = oms.current();
273 if (omv.type() == OopMapValue::derived_oop_value) {
274 int pos = find_derived_position(omv, start);
275 assert(pos > 0, "");
276 insert(omv, pos);
277 }
278 }
279 }
280
281 void OopMapSort::print() {
282 for (int i = 0; i < _count; ++i) {
283 OopMapValue omv = _values[i];
284 if (omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value) {
285 if (omv.reg()->is_reg()) {
286 tty->print_cr("[%c][%d] -> reg (%d)", omv.type() == OopMapValue::narrowoop_value ? 'n' : 'o', i, omv.reg()->value());
287 } else {
288 tty->print_cr("[%c][%d] -> stack (%d)", omv.type() == OopMapValue::narrowoop_value ? 'n' : 'o', i, omv.reg()->reg2stack() * VMRegImpl::stack_slot_size);
289 }
290 } else {
291 if (omv.content_reg()->is_reg()) {
292 tty->print_cr("[d][%d] -> reg (%d) stack (%d)", i, omv.content_reg()->value(), omv.reg()->reg2stack() * VMRegImpl::stack_slot_size);
293 } else if (omv.reg()->is_reg()) {
294 tty->print_cr("[d][%d] -> stack (%d) reg (%d)", i, omv.content_reg()->reg2stack() * VMRegImpl::stack_slot_size, omv.reg()->value());
295 } else {
296 int derived_offset = omv.reg()->reg2stack() * VMRegImpl::stack_slot_size;
297 int base_offset = omv.content_reg()->reg2stack() * VMRegImpl::stack_slot_size;
298 tty->print_cr("[d][%d] -> stack (%x) stack (%x)", i, base_offset, derived_offset);
299 }
300 }
301 }
302 }
303
304 void OopMap::copy_and_sort_data_to(address addr) const {
305 OopMapSort sort(this);
306 sort.sort();
307 CompressedWriteStream* stream = new CompressedWriteStream(_write_stream->position());
308 sort.write(stream);
309
310 assert(stream->position() == write_stream()->position(), "");
311 memcpy(addr, stream->buffer(), stream->position());
312 }
313
314 int OopMap::heap_size() const {
315 int size = sizeof(OopMap);
316 int align = sizeof(void *) - 1;
317 size += write_stream()->position();
318 // Align to a reasonable ending point
319 size = ((size+align) & ~align);
320 return size;
321 }
322
323 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
324 // slots to hold 4-byte values like ints and floats in the LP64 build.
325 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
326
327 assert(reg->value() < _locs_length, "too big reg value for stack size");
328 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
329 debug_only( _locs_used[reg->value()] = x; )
330
331 OopMapValue o(reg, x, optional);
332 o.write_on(write_stream());
333 increment_count();
334 if (x == OopMapValue::oop_value || x == OopMapValue::narrowoop_value) {
335 increment_num_oops();
336 } else if (x == OopMapValue::derived_oop_value) {
337 set_has_derived_oops(true);
338 }
339 }
340
341
342 void OopMap::set_oop(VMReg reg) {
343 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
344 }
345
346
347 void OopMap::set_narrowoop(VMReg reg) {
348 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
349 }
350
351
352 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
353 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
354 }
355
356
357 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
358 if( reg == derived_from_local_register ) {
359 // Actually an oop, derived shares storage with base,
360 set_oop(reg);
361 } else {
362 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
363 }
364 }
365
366 // OopMapSet
367
368 OopMapSet::OopMapSet() : _list(MinOopMapAllocation) {}
369
370 int OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
371 map->set_offset(pc_offset);
372
373 #ifdef ASSERT
374 if(_list.length() > 0) {
375 OopMap* last = _list.last();
376 if (last->offset() == map->offset() ) {
377 fatal("OopMap inserted twice");
378 }
379 if (last->offset() > map->offset()) {
380 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
381 _list.length(),last->offset(),_list.length()+1,map->offset());
382 }
383 }
384 #endif // ASSERT
385
386 int index = add(map);
387 map->_index = index;
388 return index;
389 }
390
391 class AddDerivedOop : public DerivedOopClosure {
392 public:
393 enum {
394 SkipNull = true, NeedsLock = true
395 };
396
397 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {
398 #if COMPILER2_OR_JVMCI
399 DerivedPointerTable::add(derived, base);
400 #endif // COMPILER2_OR_JVMCI
401 }
402 };
403
404 class ProcessDerivedOop : public DerivedOopClosure {
405 OopClosure* _oop_cl;
406
407 public:
408 ProcessDerivedOop(OopClosure* oop_cl) :
409 _oop_cl(oop_cl) {}
410
411 enum {
412 SkipNull = true, NeedsLock = true
413 };
414
415 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {
416 // All derived pointers must be processed before the base pointer of any derived pointer is processed.
417 // Otherwise, if two derived pointers use the same base, the second derived pointer will get an obscured
418 // offset, if the base pointer is processed in the first derived pointer.
419 derived_pointer derived_base = to_derived_pointer(*reinterpret_cast<intptr_t*>(base));
420 intptr_t offset = *derived - derived_base;
421 *derived = derived_base;
422 _oop_cl->do_oop((oop*)derived);
423 *derived = *derived + offset;
424 }
425 };
426
427 class IgnoreDerivedOop : public DerivedOopClosure {
428 OopClosure* _oop_cl;
429
430 public:
431 enum {
432 SkipNull = true, NeedsLock = true
433 };
434
435 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {}
436 };
437
438 void OopMapSet::oops_do(const frame* fr, const RegisterMap* reg_map, OopClosure* f, DerivedPointerIterationMode mode) {
439 find_map(fr)->oops_do(fr, reg_map, f, mode);
440 }
441
442 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f, DerivedOopClosure* df) {
443 find_map(fr)->oops_do(fr, reg_map, f, df);
444 }
445
446 void ImmutableOopMap::oops_do(const frame *fr, const RegisterMap *reg_map,
447 OopClosure* oop_fn, DerivedOopClosure* derived_oop_fn) const {
448 assert(derived_oop_fn != nullptr, "sanity");
449 OopMapDo<OopClosure, DerivedOopClosure, SkipNullValue> visitor(oop_fn, derived_oop_fn);
450 visitor.oops_do(fr, reg_map, this);
451 }
452
453 void ImmutableOopMap::oops_do(const frame *fr, const RegisterMap *reg_map,
454 OopClosure* oop_fn, DerivedPointerIterationMode derived_mode) const {
455 ProcessDerivedOop process_cl(oop_fn);
456 AddDerivedOop add_cl;
457 IgnoreDerivedOop ignore_cl;
458 DerivedOopClosure* derived_cl;
459 switch (derived_mode) {
460 case DerivedPointerIterationMode::_directly:
461 derived_cl = &process_cl;
462 break;
463 case DerivedPointerIterationMode::_with_table:
464 derived_cl = &add_cl;
465 break;
466 case DerivedPointerIterationMode::_ignore:
467 derived_cl = &ignore_cl;
468 break;
469 default:
470 guarantee (false, "unreachable");
471 }
472 OopMapDo<OopClosure, DerivedOopClosure, SkipNullValue> visitor(oop_fn, derived_cl);
473 visitor.oops_do(fr, reg_map, this);
474 }
475
476 void ImmutableOopMap::all_type_do(const frame *fr, OopMapClosure* fn) const {
477 OopMapValue omv;
478 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
479 omv = oms.current();
480 if (fn->handle_type(omv.type())) {
481 fn->do_value(omv.reg(), omv.type());
482 }
483 }
484 }
485
486 void ImmutableOopMap::all_type_do(const frame *fr, OopMapValue::oop_types type, OopMapClosure* fn) const {
487 OopMapValue omv;
488 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
489 omv = oms.current();
490 if (omv.type() == type) {
491 fn->do_value(omv.reg(), omv.type());
492 }
493 }
494 }
495
496 static void update_register_map1(const ImmutableOopMap* oopmap, const frame* fr, RegisterMap* reg_map) {
497 for (OopMapStream oms(oopmap); !oms.is_done(); oms.next()) {
498 OopMapValue omv = oms.current();
499 if (omv.type() == OopMapValue::callee_saved_value) {
500 VMReg reg = omv.content_reg();
501 address loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
502 reg_map->set_location(reg, loc);
503 }
504 }
505 }
506
507 // Update callee-saved register info for the following frame
508 void ImmutableOopMap::update_register_map(const frame *fr, RegisterMap *reg_map) const {
509 CodeBlob* cb = fr->cb();
510 assert(cb != nullptr, "no codeblob");
511 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
512 assert( reg_map->_update_for_id == nullptr || fr->is_older(reg_map->_update_for_id),
513 "already updated this map; do not 'update' it twice!" );
514 debug_only(reg_map->_update_for_id = fr->id());
515
516 // Check if caller must update oop argument
517 assert((reg_map->include_argument_oops() ||
518 !cb->caller_must_gc_arguments(reg_map->thread())),
519 "include_argument_oops should already be set");
520
521 // Scan through oopmap and find location of all callee-saved registers
522 // (we do not do update in place, since info could be overwritten)
523
524 update_register_map1(this, fr, reg_map);
525 }
526
527 const ImmutableOopMap* OopMapSet::find_map(const frame *fr) {
528 return find_map(fr->cb(), fr->pc());
529 }
530
531 const ImmutableOopMap* OopMapSet::find_map(const CodeBlob* cb, address pc) {
532 assert(cb != nullptr, "no codeblob");
533 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
534 assert(map != nullptr, "no ptr map found");
535 return map;
536 }
537
538 // Update callee-saved register info for the following frame
539 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
540 find_map(fr)->update_register_map(fr, reg_map);
541 }
542
543 //=============================================================================
544 // Non-Product code
545
546 #ifndef PRODUCT
547 void OopMapSet::trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
548 // Print oopmap and regmap
549 tty->print_cr("------ ");
550 CodeBlob* cb = fr->cb();
551 const ImmutableOopMapSet* maps = cb->oop_maps();
552 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
553 map->print();
554 if( cb->is_nmethod() ) {
555 nmethod* nm = (nmethod*)cb;
556 // native wrappers have no scope data, it is implied
557 if (nm->is_native_method()) {
558 tty->print("bci: 0 (native)");
559 } else {
560 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
561 tty->print("bci: %d ",scope->bci());
562 }
563 }
564 tty->cr();
565 fr->print_on(tty);
566 tty->print(" ");
567 cb->print_value_on(tty); tty->cr();
568 if (reg_map != nullptr) {
569 reg_map->print();
570 }
571 tty->print_cr("------ ");
572
573 }
574 #endif // PRODUCT
575
576 // Printing code is present in product build for -XX:+PrintAssembly.
577
578 static
579 void print_register_type(OopMapValue::oop_types x, VMReg optional,
580 outputStream* st) {
581 switch( x ) {
582 case OopMapValue::oop_value:
583 st->print("Oop");
584 break;
585 case OopMapValue::narrowoop_value:
586 st->print("NarrowOop");
587 break;
588 case OopMapValue::callee_saved_value:
589 st->print("Callers_");
590 optional->print_on(st);
591 break;
592 case OopMapValue::derived_oop_value:
593 st->print("Derived_oop_");
594 optional->print_on(st);
595 break;
596 default:
597 ShouldNotReachHere();
598 }
599 }
600
601 void OopMapValue::print_on(outputStream* st) const {
602 reg()->print_on(st);
603 st->print("=");
604 print_register_type(type(),content_reg(),st);
605 st->print(" ");
606 }
607
608 void OopMapValue::print() const { print_on(tty); }
609
610 void ImmutableOopMap::print_on(outputStream* st) const {
611 OopMapValue omv;
612 st->print("ImmutableOopMap {");
613 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
614 omv = oms.current();
615 omv.print_on(st);
616 }
617 st->print("}");
618 }
619
620 void ImmutableOopMap::print() const { print_on(tty); }
621
622 void OopMap::print_on(outputStream* st) const {
623 OopMapValue omv;
624 st->print("OopMap {");
625 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
626 omv = oms.current();
627 omv.print_on(st);
628 }
629 // Print hex offset in addition.
630 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
631 }
632
633 void OopMap::print() const { print_on(tty); }
634
635 void ImmutableOopMapSet::print_on(outputStream* st) const {
636 const ImmutableOopMap* last = nullptr;
637 const int len = count();
638
639 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
640
641 for (int i = 0; i < len; i++) {
642 const ImmutableOopMapPair* pair = pair_at(i);
643 const ImmutableOopMap* map = pair->get_from(this);
644 if (map != last) {
645 st->cr();
646 map->print_on(st);
647 st->print(" pc offsets: ");
648 }
649 last = map;
650 st->print("%d ", pair->pc_offset());
651 }
652 st->cr();
653 }
654
655 void ImmutableOopMapSet::print() const { print_on(tty); }
656
657 void OopMapSet::print_on(outputStream* st) const {
658 const int len = _list.length();
659
660 st->print_cr("OopMapSet contains %d OopMaps", len);
661
662 for( int i = 0; i < len; i++) {
663 OopMap* m = at(i);
664 st->print_cr("#%d ",i);
665 m->print_on(st);
666 st->cr();
667 }
668 st->cr();
669 }
670
671 void OopMapSet::print() const { print_on(tty); }
672
673 bool OopMap::equals(const OopMap* other) const {
674 if (other->_omv_count != _omv_count) {
675 return false;
676 }
677 if (other->write_stream()->position() != write_stream()->position()) {
678 return false;
679 }
680 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
681 return false;
682 }
683 return true;
684 }
685
686 int ImmutableOopMapSet::find_slot_for_offset(int pc_offset) const {
687 // we might not have an oopmap at asynchronous (non-safepoint) stackwalks
688 ImmutableOopMapPair* pairs = get_pairs();
689 for (int i = 0; i < _count; ++i) {
690 if (pairs[i].pc_offset() >= pc_offset) {
691 ImmutableOopMapPair* last = &pairs[i];
692 return last->pc_offset() == pc_offset ? i : -1;
693 }
694 }
695 return -1;
696 }
697
698 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
699 ImmutableOopMapPair* pairs = get_pairs();
700 ImmutableOopMapPair* last = nullptr;
701
702 for (int i = 0; i < _count; ++i) {
703 if (pairs[i].pc_offset() >= pc_offset) {
704 last = &pairs[i];
705 break;
706 }
707 }
708
709 // Heal Coverity issue: potential index out of bounds access.
710 guarantee(last != nullptr, "last may not be null");
711 assert(last->pc_offset() == pc_offset, "oopmap not found");
712 return last->get_from(this);
713 }
714
715 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap)
716 : _count(oopmap->count()), _num_oops(oopmap->num_oops()) {
717 _num_oops = oopmap->num_oops();
718 _has_derived_oops = oopmap->has_derived_oops();
719 address addr = data_addr();
720 oopmap->copy_and_sort_data_to(addr);
721 }
722
723 bool ImmutableOopMap::has_any(OopMapValue::oop_types type) const {
724 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
725 if (oms.current().type() == type) {
726 return true;
727 }
728 }
729 return false;
730 }
731
732 #ifdef ASSERT
733 int ImmutableOopMap::nr_of_bytes() const {
734 OopMapStream oms(this);
735
736 while (!oms.is_done()) {
737 oms.next();
738 }
739 return sizeof(ImmutableOopMap) + oms.stream_position();
740 }
741 #endif
742
743 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(nullptr), _last(nullptr), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(nullptr) {
744 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
745 }
746
747 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
748 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
749 }
750
751 int ImmutableOopMapBuilder::heap_size() {
752 int base = sizeof(ImmutableOopMapSet);
753 base = align_up(base, 8);
754
755 // all of ours pc / offset pairs
756 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
757 pairs = align_up(pairs, 8);
758
759 for (int i = 0; i < _set->size(); ++i) {
760 int size = 0;
761 OopMap* map = _set->at(i);
762
763 if (is_empty(map)) {
764 /* only keep a single empty map in the set */
765 if (has_empty()) {
766 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
767 } else {
768 _empty_offset = _offset;
769 _empty = map;
770 size = size_for(map);
771 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
772 }
773 } else if (is_last_duplicate(map)) {
774 /* if this entry is identical to the previous one, just point it there */
775 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
776 } else {
777 /* not empty, not an identical copy of the previous entry */
778 size = size_for(map);
779 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
780 _last_offset = _offset;
781 _last = map;
782 }
783
784 assert(_mapping[i]._map == map, "check");
785 _offset += size;
786 }
787
788 int total = base + pairs + _offset;
789 DEBUG_ONLY(total += 8);
790 _required = total;
791 return total;
792 }
793
794 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
795 assert(offset < set->nr_of_bytes(), "check");
796 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
797 }
798
799 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
800 fill_pair(pair, map, offset, set);
801 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
802
803 new (addr) ImmutableOopMap(map);
804 return size_for(map);
805 }
806
807 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
808 ImmutableOopMapPair* pairs = set->get_pairs();
809
810 for (int i = 0; i < set->count(); ++i) {
811 const OopMap* map = _mapping[i]._map;
812 ImmutableOopMapPair* pair = nullptr;
813 int size = 0;
814
815 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
816 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
817 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
818 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
819 }
820
821 //const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
822 //assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
823 }
824 }
825
826 #ifdef ASSERT
827 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
828 for (int i = 0; i < 8; ++i) {
829 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
830 }
831
832 for (int i = 0; i < set->count(); ++i) {
833 const ImmutableOopMapPair* pair = set->pair_at(i);
834 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
835 const ImmutableOopMap* map = pair->get_from(set);
836 int nr_of_bytes = map->nr_of_bytes();
837 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
838 }
839 }
840 #endif
841
842 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
843 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
844
845 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
846 fill(_new_set, _required);
847
848 DEBUG_ONLY(verify(buffer, _required, _new_set));
849
850 return _new_set;
851 }
852
853 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
854 _required = heap_size();
855
856 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
857 address buffer = NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
858 return generate_into(buffer);
859 }
860
861 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
862 ResourceMark mark;
863 ImmutableOopMapBuilder builder(oopmap_set);
864 return builder.build();
865 }
866
867 void ImmutableOopMapSet::operator delete(void* p) {
868 FREE_C_HEAP_ARRAY(unsigned char, p);
869 }
870
871 //------------------------------DerivedPointerTable---------------------------
872
873 #if COMPILER2_OR_JVMCI
874
875 class DerivedPointerTable::Entry : public CHeapObj<mtCompiler> {
876 derived_pointer* _location; // Location of derived pointer, also pointing to base
877 intptr_t _offset; // Offset from base pointer
878 Entry* volatile _next;
879
880 static Entry* volatile* next_ptr(Entry& entry) { return &entry._next; }
881
882 public:
883 Entry(derived_pointer* location, intptr_t offset) :
884 _location(location), _offset(offset), _next(nullptr) {}
885
886 derived_pointer* location() const { return _location; }
887 intptr_t offset() const { return _offset; }
888 Entry* next() const { return _next; }
889
890 typedef LockFreeStack<Entry, &next_ptr> List;
891 static List* _list;
892 };
893
894 DerivedPointerTable::Entry::List* DerivedPointerTable::Entry::_list = nullptr;
895 bool DerivedPointerTable::_active = false;
896
897 bool DerivedPointerTable::is_empty() {
898 return Entry::_list == nullptr || Entry::_list->empty();
899 }
900
901 void DerivedPointerTable::clear() {
902 // The first time, we create the list. Otherwise it should be
903 // empty. If not, then we have probably forgotton to call
904 // update_pointers after last GC/Scavenge.
905 assert (!_active, "should not be active");
906 assert(is_empty(), "table not empty");
907 if (Entry::_list == nullptr) {
908 void* mem = NEW_C_HEAP_OBJ(Entry::List, mtCompiler);
909 Entry::_list = ::new (mem) Entry::List();
910 }
911 _active = true;
912 }
913
914 void DerivedPointerTable::add(derived_pointer* derived_loc, derived_base* base_loc) {
915 assert(Universe::heap()->is_in_or_null((void*)*base_loc), "not an oop");
916 assert(derived_loc != (void*)base_loc, "Base and derived in same location");
917 derived_pointer base_loc_as_derived_pointer =
918 static_cast<derived_pointer>(reinterpret_cast<intptr_t>(base_loc));
919 assert(*derived_loc != base_loc_as_derived_pointer, "location already added");
920 assert(Entry::_list != nullptr, "list must exist");
921 assert(is_active(), "table must be active here");
922 intptr_t offset = *derived_loc - to_derived_pointer(*reinterpret_cast<intptr_t*>(base_loc));
923 // This assert is invalid because derived pointers can be
924 // arbitrarily far away from their base.
925 // assert(offset >= -1000000, "wrong derived pointer info");
926
927 if (TraceDerivedPointers) {
928 tty->print_cr(
929 "Add derived pointer@" INTPTR_FORMAT
930 " - Derived: " INTPTR_FORMAT
931 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: %zd)",
932 p2i(derived_loc), derived_pointer_value(*derived_loc), intptr_t(*base_loc), p2i(base_loc), offset
933 );
934 }
935 // Set derived oop location to point to base.
936 *derived_loc = base_loc_as_derived_pointer;
937 Entry* entry = new Entry(derived_loc, offset);
938 Entry::_list->push(*entry);
939 }
940
941 void DerivedPointerTable::update_pointers() {
942 assert(Entry::_list != nullptr, "list must exist");
943 Entry* entries = Entry::_list->pop_all();
944 while (entries != nullptr) {
945 Entry* entry = entries;
946 entries = entry->next();
947 derived_pointer* derived_loc = entry->location();
948 intptr_t offset = entry->offset();
949 // The derived oop was setup to point to location of base
950 oop base = **reinterpret_cast<oop**>(derived_loc);
951 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
952
953 derived_pointer derived_base = to_derived_pointer(cast_from_oop<intptr_t>(base));
954 *derived_loc = derived_base + offset;
955 assert(*derived_loc - derived_base == offset, "sanity check");
956
957 // assert(offset >= 0 && offset <= (intptr_t)(base->size() << LogHeapWordSize), "offset: %ld base->size: %zu relative: %d", offset, base->size() << LogHeapWordSize, *(intptr_t*)derived_loc <= 0);
958
959 if (TraceDerivedPointers) {
960 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
961 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: %zd)",
962 p2i(derived_loc), derived_pointer_value(*derived_loc), p2i(base), offset);
963 }
964
965 // Delete entry
966 delete entry;
967 }
968 assert(Entry::_list->empty(), "invariant");
969 _active = false;
970 }
971
972 #endif // COMPILER2_OR_JVMCI