1 /*
2 * Copyright (c) 1998, 2024, 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/codeBlob.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/nmethod.hpp"
29 #include "code/scopeDesc.hpp"
30 #include "compiler/oopMap.inline.hpp"
31 #include "gc/shared/collectedHeap.hpp"
32 #include "logging/log.hpp"
33 #include "logging/logStream.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/iterator.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "oops/inlineKlass.hpp"
38 #include "oops/compressedOops.hpp"
39 #include "runtime/atomic.hpp"
40 #include "runtime/frame.inline.hpp"
41 #include "runtime/handles.inline.hpp"
42 #include "runtime/signature.hpp"
43 #include "runtime/stackWatermarkSet.inline.hpp"
44 #include "utilities/align.hpp"
45 #include "utilities/lockFreeStack.hpp"
46 #ifdef COMPILER1
47 #include "c1/c1_Defs.hpp"
48 #endif
49 #ifdef COMPILER2
50 #include "opto/optoreg.hpp"
51 #endif
52 #if INCLUDE_JVMCI
53 #include "jvmci/jvmci_globals.hpp"
54 #endif
55
56 static_assert(sizeof(oop) == sizeof(intptr_t), "Derived pointer sanity check");
57
58 static inline intptr_t derived_pointer_value(derived_pointer p) {
59 return static_cast<intptr_t>(p);
60 }
61
62 static inline derived_pointer to_derived_pointer(intptr_t obj) {
63 return static_cast<derived_pointer>(obj);
64 }
65
66 static inline intptr_t operator-(derived_pointer p, derived_pointer p1) {
67 return derived_pointer_value(p) - derived_pointer_value(p1);
68 }
69
70 static inline derived_pointer operator+(derived_pointer p, intptr_t offset) {
71 return static_cast<derived_pointer>(derived_pointer_value(p) + offset);
72 }
73
74 // OopMapStream
75
76 OopMapStream::OopMapStream(const OopMap* oop_map)
77 : _stream(oop_map->write_stream()->buffer()) {
78 _size = oop_map->omv_count();
79 _position = 0;
80 _valid_omv = false;
81 }
82
83 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map)
84 : _stream(oop_map->data_addr()) {
85 _size = oop_map->count();
86 _position = 0;
87 _valid_omv = false;
88 }
89
90 void OopMapStream::find_next() {
91 if (_position++ < _size) {
92 _omv.read_from(&_stream);
93 _valid_omv = true;
94 return;
95 }
96 _valid_omv = false;
97 }
98
99
100 // OopMap
101
102 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
103 // slots to hold 4-byte values like ints and floats in the LP64 build.
104 OopMap::OopMap(int frame_size, int arg_count) {
105 // OopMaps are usually quite so small, so pick a small initial size
106 set_write_stream(new CompressedWriteStream(32));
107 set_omv_count(0);
108 _num_oops = 0;
109 _has_derived_oops = false;
110 _index = -1;
111
112 #ifdef ASSERT
113 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
114 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
115 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
116 #endif
117 }
118
119
120 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
121 // This constructor does a deep copy
122 // of the source OopMap.
123 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
124 set_omv_count(0);
125 set_offset(source->offset());
126 _num_oops = source->num_oops();
127 _has_derived_oops = source->has_derived_oops();
128 _index = -1;
129
130 #ifdef ASSERT
131 _locs_length = source->_locs_length;
132 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
133 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
134 #endif
135
136 // We need to copy the entries too.
137 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
138 OopMapValue omv = oms.current();
139 omv.write_on(write_stream());
140 increment_count();
141 }
142 }
143
144
145 OopMap* OopMap::deep_copy() {
146 return new OopMap(_deep_copy_token, this);
147 }
148
149 void OopMap::copy_data_to(address addr) const {
150 memcpy(addr, write_stream()->buffer(), write_stream()->position());
151 }
152
153 class OopMapSort {
154 private:
155 const OopMap* _map;
156 OopMapValue* _values;
157 int _count;
158
159 public:
160 OopMapSort(const OopMap* map) : _map(map), _count(0) {
161 _values = NEW_RESOURCE_ARRAY(OopMapValue, _map->omv_count());
162 }
163
164 void sort();
165
166 void print();
167
168 void write(CompressedWriteStream* stream) {
169 for (int i = 0; i < _count; ++i) {
170 _values[i].write_on(stream);
171 }
172 }
173
174 private:
175 int find_derived_position(OopMapValue omv, int start) {
176 assert(omv.type() == OopMapValue::derived_oop_value, "");
177
178 VMReg base = omv.content_reg();
179 int i = start;
180
181 for (; i < _count; ++i) {
182 if (base == _values[i].reg()) {
183
184 for (int n = i + 1; n < _count; ++n) {
185 if (_values[i].type() != OopMapValue::derived_oop_value || _values[i].content_reg() != base) {
186 return n;
187 }
188
189 if (derived_cost(_values[i]) > derived_cost(omv)) {
190 return n;
191 }
192 }
193 return _count;
194 }
195 }
196
197 assert(false, "failed to find base");
198 return -1;
199 }
200
201 int find_position(OopMapValue omv, int start) {
202 assert(omv.type() != OopMapValue::derived_oop_value, "");
203
204 int i = start;
205 for (; i < _count; ++i) {
206 if (omv_cost(_values[i]) > omv_cost(omv)) {
207 return i;
208 }
209 }
210 assert(i < _map->omv_count(), "bounds check");
211 return i;
212 }
213
214 void insert(OopMapValue value, int pos) {
215 assert(pos >= 0 && pos < _map->omv_count(), "bounds check");
216 assert(pos <= _count, "sanity");
217
218 if (pos < _count) {
219 OopMapValue prev = _values[pos];
220
221 for (int i = pos; i < _count; ++i) {
222 OopMapValue tmp = _values[i+1];
223 _values[i+1] = prev;
224 prev = tmp;
225 }
226 }
227 _values[pos] = value;
228
229 ++_count;
230 }
231
232 int omv_cost(OopMapValue omv) {
233 assert(omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value, "");
234 return reg_cost(omv.reg());
235 }
236
237 int reg_cost(VMReg reg) {
238 if (reg->is_reg()) {
239 return 0;
240 }
241 return reg->reg2stack() * VMRegImpl::stack_slot_size;
242 }
243
244 int derived_cost(OopMapValue omv) {
245 return reg_cost(omv.reg());
246 }
247 };
248
249 void OopMapSort::sort() {
250 #ifdef ASSERT
251 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
252 OopMapValue omv = oms.current();
253 assert(omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value ||
254 omv.type() == OopMapValue::derived_oop_value || omv.type() == OopMapValue::callee_saved_value, "");
255 }
256 #endif
257
258 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
259 if (oms.current().type() == OopMapValue::callee_saved_value) {
260 insert(oms.current(), _count);
261 }
262 }
263
264 int start = _count;
265 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
266 OopMapValue omv = oms.current();
267 if (omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value) {
268 int pos = find_position(omv, start);
269 insert(omv, pos);
270 }
271 }
272
273 for (OopMapStream oms(_map); !oms.is_done(); oms.next()) {
274 OopMapValue omv = oms.current();
275 if (omv.type() == OopMapValue::derived_oop_value) {
276 int pos = find_derived_position(omv, start);
277 assert(pos > 0, "");
278 insert(omv, pos);
279 }
280 }
281 }
282
283 void OopMapSort::print() {
284 for (int i = 0; i < _count; ++i) {
285 OopMapValue omv = _values[i];
286 if (omv.type() == OopMapValue::oop_value || omv.type() == OopMapValue::narrowoop_value) {
287 if (omv.reg()->is_reg()) {
288 tty->print_cr("[%c][%d] -> reg (%d)", omv.type() == OopMapValue::narrowoop_value ? 'n' : 'o', i, omv.reg()->value());
289 } else {
290 tty->print_cr("[%c][%d] -> stack (%d)", omv.type() == OopMapValue::narrowoop_value ? 'n' : 'o', i, omv.reg()->reg2stack() * VMRegImpl::stack_slot_size);
291 }
292 } else {
293 if (omv.content_reg()->is_reg()) {
294 tty->print_cr("[d][%d] -> reg (%d) stack (%d)", i, omv.content_reg()->value(), omv.reg()->reg2stack() * VMRegImpl::stack_slot_size);
295 } else if (omv.reg()->is_reg()) {
296 tty->print_cr("[d][%d] -> stack (%d) reg (%d)", i, omv.content_reg()->reg2stack() * VMRegImpl::stack_slot_size, omv.reg()->value());
297 } else {
298 int derived_offset = omv.reg()->reg2stack() * VMRegImpl::stack_slot_size;
299 int base_offset = omv.content_reg()->reg2stack() * VMRegImpl::stack_slot_size;
300 tty->print_cr("[d][%d] -> stack (%x) stack (%x)", i, base_offset, derived_offset);
301 }
302 }
303 }
304 }
305
306 void OopMap::copy_and_sort_data_to(address addr) const {
307 OopMapSort sort(this);
308 sort.sort();
309 CompressedWriteStream* stream = new CompressedWriteStream(_write_stream->position());
310 sort.write(stream);
311
312 assert(stream->position() == write_stream()->position(), "");
313 memcpy(addr, stream->buffer(), stream->position());
314 }
315
316 int OopMap::heap_size() const {
317 int size = sizeof(OopMap);
318 int align = sizeof(void *) - 1;
319 size += write_stream()->position();
320 // Align to a reasonable ending point
321 size = ((size+align) & ~align);
322 return size;
323 }
324
325 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
326 // slots to hold 4-byte values like ints and floats in the LP64 build.
327 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
328
329 assert(reg->value() < _locs_length, "too big reg value for stack size");
330 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
331 debug_only( _locs_used[reg->value()] = x; )
332
333 OopMapValue o(reg, x, optional);
334 o.write_on(write_stream());
335 increment_count();
336 if (x == OopMapValue::oop_value || x == OopMapValue::narrowoop_value) {
337 increment_num_oops();
338 } else if (x == OopMapValue::derived_oop_value) {
339 set_has_derived_oops(true);
340 }
341 }
342
343
344 void OopMap::set_oop(VMReg reg) {
345 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
346 }
347
348
349 void OopMap::set_narrowoop(VMReg reg) {
350 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
351 }
352
353
354 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
355 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
356 }
357
358
359 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
360 if( reg == derived_from_local_register ) {
361 // Actually an oop, derived shares storage with base,
362 set_oop(reg);
363 } else {
364 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
365 }
366 }
367
368 // OopMapSet
369
370 OopMapSet::OopMapSet() : _list(MinOopMapAllocation) {}
371
372 int OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
373 map->set_offset(pc_offset);
374
375 #ifdef ASSERT
376 if(_list.length() > 0) {
377 OopMap* last = _list.last();
378 if (last->offset() == map->offset() ) {
379 fatal("OopMap inserted twice");
380 }
381 if (last->offset() > map->offset()) {
382 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
383 _list.length(),last->offset(),_list.length()+1,map->offset());
384 }
385 }
386 #endif // ASSERT
387
388 int index = add(map);
389 map->_index = index;
390 return index;
391 }
392
393 class AddDerivedOop : public DerivedOopClosure {
394 public:
395 enum {
396 SkipNull = true, NeedsLock = true
397 };
398
399 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {
400 #if COMPILER2_OR_JVMCI
401 DerivedPointerTable::add(derived, base);
402 #endif // COMPILER2_OR_JVMCI
403 }
404 };
405
406 class ProcessDerivedOop : public DerivedOopClosure {
407 OopClosure* _oop_cl;
408
409 public:
410 ProcessDerivedOop(OopClosure* oop_cl) :
411 _oop_cl(oop_cl) {}
412
413 enum {
414 SkipNull = true, NeedsLock = true
415 };
416
417 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {
418 // All derived pointers must be processed before the base pointer of any derived pointer is processed.
419 // Otherwise, if two derived pointers use the same base, the second derived pointer will get an obscured
420 // offset, if the base pointer is processed in the first derived pointer.
421 derived_pointer derived_base = to_derived_pointer(*reinterpret_cast<intptr_t*>(base));
422 intptr_t offset = *derived - derived_base;
423 *derived = derived_base;
424 _oop_cl->do_oop((oop*)derived);
425 *derived = *derived + offset;
426 }
427 };
428
429 class IgnoreDerivedOop : public DerivedOopClosure {
430 OopClosure* _oop_cl;
431
432 public:
433 enum {
434 SkipNull = true, NeedsLock = true
435 };
436
437 virtual void do_derived_oop(derived_base* base, derived_pointer* derived) {}
438 };
439
440 void OopMapSet::oops_do(const frame* fr, const RegisterMap* reg_map, OopClosure* f, DerivedPointerIterationMode mode) {
441 find_map(fr)->oops_do(fr, reg_map, f, mode);
442 }
443
444 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f, DerivedOopClosure* df) {
445 find_map(fr)->oops_do(fr, reg_map, f, df);
446 }
447
448 void ImmutableOopMap::oops_do(const frame *fr, const RegisterMap *reg_map,
449 OopClosure* oop_fn, DerivedOopClosure* derived_oop_fn) const {
450 assert(derived_oop_fn != nullptr, "sanity");
451 OopMapDo<OopClosure, DerivedOopClosure, SkipNullValue> visitor(oop_fn, derived_oop_fn);
452 visitor.oops_do(fr, reg_map, this);
453 }
454
455 void ImmutableOopMap::oops_do(const frame *fr, const RegisterMap *reg_map,
456 OopClosure* oop_fn, DerivedPointerIterationMode derived_mode) const {
457 ProcessDerivedOop process_cl(oop_fn);
458 AddDerivedOop add_cl;
459 IgnoreDerivedOop ignore_cl;
460 DerivedOopClosure* derived_cl;
461 switch (derived_mode) {
462 case DerivedPointerIterationMode::_directly:
463 derived_cl = &process_cl;
464 break;
465 case DerivedPointerIterationMode::_with_table:
466 derived_cl = &add_cl;
467 break;
468 case DerivedPointerIterationMode::_ignore:
469 derived_cl = &ignore_cl;
470 break;
471 default:
472 guarantee (false, "unreachable");
473 }
474 OopMapDo<OopClosure, DerivedOopClosure, SkipNullValue> visitor(oop_fn, derived_cl);
475 visitor.oops_do(fr, reg_map, this);
476 }
477
478 void ImmutableOopMap::all_type_do(const frame *fr, OopMapClosure* fn) const {
479 OopMapValue omv;
480 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
481 omv = oms.current();
482 if (fn->handle_type(omv.type())) {
483 fn->do_value(omv.reg(), omv.type());
484 }
485 }
486 }
487
488 void ImmutableOopMap::all_type_do(const frame *fr, OopMapValue::oop_types type, OopMapClosure* fn) const {
489 OopMapValue omv;
490 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
491 omv = oms.current();
492 if (omv.type() == type) {
493 fn->do_value(omv.reg(), omv.type());
494 }
495 }
496 }
497
498 static void update_register_map1(const ImmutableOopMap* oopmap, const frame* fr, RegisterMap* reg_map) {
499 for (OopMapStream oms(oopmap); !oms.is_done(); oms.next()) {
500 OopMapValue omv = oms.current();
501 if (omv.type() == OopMapValue::callee_saved_value) {
502 VMReg reg = omv.content_reg();
503 address loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
504 reg_map->set_location(reg, loc);
505 }
506 }
507 }
508
509 // Update callee-saved register info for the following frame
510 void ImmutableOopMap::update_register_map(const frame *fr, RegisterMap *reg_map) const {
511 CodeBlob* cb = fr->cb();
512 assert(cb != nullptr, "no codeblob");
513 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
514 assert( reg_map->_update_for_id == nullptr || fr->is_older(reg_map->_update_for_id),
515 "already updated this map; do not 'update' it twice!" );
516 debug_only(reg_map->_update_for_id = fr->id());
517
518 // Check if caller must update oop argument
519 assert((reg_map->include_argument_oops() ||
520 !cb->caller_must_gc_arguments(reg_map->thread())),
521 "include_argument_oops should already be set");
522
523 // Scan through oopmap and find location of all callee-saved registers
524 // (we do not do update in place, since info could be overwritten)
525
526 update_register_map1(this, fr, reg_map);
527 }
528
529 const ImmutableOopMap* OopMapSet::find_map(const frame *fr) {
530 return find_map(fr->cb(), fr->pc());
531 }
532
533 const ImmutableOopMap* OopMapSet::find_map(const CodeBlob* cb, address pc) {
534 assert(cb != nullptr, "no codeblob");
535 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
536 assert(map != nullptr, "no ptr map found");
537 return map;
538 }
539
540 // Update callee-saved register info for the following frame
541 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
542 find_map(fr)->update_register_map(fr, reg_map);
543 }
544
545 //=============================================================================
546 // Non-Product code
547
548 #ifndef PRODUCT
549 void OopMapSet::trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
550 // Print oopmap and regmap
551 tty->print_cr("------ ");
552 CodeBlob* cb = fr->cb();
553 const ImmutableOopMapSet* maps = cb->oop_maps();
554 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
555 map->print();
556 if( cb->is_nmethod() ) {
557 nmethod* nm = (nmethod*)cb;
558 // native wrappers have no scope data, it is implied
559 if (nm->is_native_method()) {
560 tty->print("bci: 0 (native)");
561 } else {
562 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
563 tty->print("bci: %d ",scope->bci());
564 }
565 }
566 tty->cr();
567 fr->print_on(tty);
568 tty->print(" ");
569 cb->print_value_on(tty); tty->cr();
570 if (reg_map != nullptr) {
571 reg_map->print();
572 }
573 tty->print_cr("------ ");
574
575 }
576 #endif // PRODUCT
577
578 // Printing code is present in product build for -XX:+PrintAssembly.
579
580 static
581 void print_register_type(OopMapValue::oop_types x, VMReg optional,
582 outputStream* st) {
583 switch( x ) {
584 case OopMapValue::oop_value:
585 st->print("Oop");
586 break;
587 case OopMapValue::narrowoop_value:
588 st->print("NarrowOop");
589 break;
590 case OopMapValue::callee_saved_value:
591 st->print("Callers_");
592 optional->print_on(st);
593 break;
594 case OopMapValue::derived_oop_value:
595 st->print("Derived_oop_");
596 optional->print_on(st);
597 break;
598 default:
599 ShouldNotReachHere();
600 }
601 }
602
603 void OopMapValue::print_on(outputStream* st) const {
604 reg()->print_on(st);
605 st->print("=");
606 print_register_type(type(),content_reg(),st);
607 st->print(" ");
608 }
609
610 void OopMapValue::print() const { print_on(tty); }
611
612 void ImmutableOopMap::print_on(outputStream* st) const {
613 OopMapValue omv;
614 st->print("ImmutableOopMap {");
615 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
616 omv = oms.current();
617 omv.print_on(st);
618 }
619 st->print("}");
620 }
621
622 void ImmutableOopMap::print() const { print_on(tty); }
623
624 void OopMap::print_on(outputStream* st) const {
625 OopMapValue omv;
626 st->print("OopMap {");
627 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
628 omv = oms.current();
629 omv.print_on(st);
630 }
631 // Print hex offset in addition.
632 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
633 }
634
635 void OopMap::print() const { print_on(tty); }
636
637 void ImmutableOopMapSet::print_on(outputStream* st) const {
638 const ImmutableOopMap* last = nullptr;
639 const int len = count();
640
641 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
642
643 for (int i = 0; i < len; i++) {
644 const ImmutableOopMapPair* pair = pair_at(i);
645 const ImmutableOopMap* map = pair->get_from(this);
646 if (map != last) {
647 st->cr();
648 map->print_on(st);
649 st->print(" pc offsets: ");
650 }
651 last = map;
652 st->print("%d ", pair->pc_offset());
653 }
654 st->cr();
655 }
656
657 void ImmutableOopMapSet::print() const { print_on(tty); }
658
659 void OopMapSet::print_on(outputStream* st) const {
660 const int len = _list.length();
661
662 st->print_cr("OopMapSet contains %d OopMaps", len);
663
664 for( int i = 0; i < len; i++) {
665 OopMap* m = at(i);
666 st->print_cr("#%d ",i);
667 m->print_on(st);
668 st->cr();
669 }
670 st->cr();
671 }
672
673 void OopMapSet::print() const { print_on(tty); }
674
675 bool OopMap::equals(const OopMap* other) const {
676 if (other->_omv_count != _omv_count) {
677 return false;
678 }
679 if (other->write_stream()->position() != write_stream()->position()) {
680 return false;
681 }
682 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
683 return false;
684 }
685 return true;
686 }
687
688 int ImmutableOopMapSet::find_slot_for_offset(int pc_offset) const {
689 // we might not have an oopmap at asynchronous (non-safepoint) stackwalks
690 ImmutableOopMapPair* pairs = get_pairs();
691 for (int i = 0; i < _count; ++i) {
692 if (pairs[i].pc_offset() >= pc_offset) {
693 ImmutableOopMapPair* last = &pairs[i];
694 return last->pc_offset() == pc_offset ? i : -1;
695 }
696 }
697 return -1;
698 }
699
700 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
701 ImmutableOopMapPair* pairs = get_pairs();
702 ImmutableOopMapPair* last = nullptr;
703
704 for (int i = 0; i < _count; ++i) {
705 if (pairs[i].pc_offset() >= pc_offset) {
706 last = &pairs[i];
707 break;
708 }
709 }
710
711 // Heal Coverity issue: potential index out of bounds access.
712 guarantee(last != nullptr, "last may not be null");
713 assert(last->pc_offset() == pc_offset, "oopmap not found");
714 return last->get_from(this);
715 }
716
717 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap)
718 : _count(oopmap->count()), _num_oops(oopmap->num_oops()) {
719 _num_oops = oopmap->num_oops();
720 _has_derived_oops = oopmap->has_derived_oops();
721 address addr = data_addr();
722 oopmap->copy_and_sort_data_to(addr);
723 }
724
725 bool ImmutableOopMap::has_any(OopMapValue::oop_types type) const {
726 for (OopMapStream oms(this); !oms.is_done(); oms.next()) {
727 if (oms.current().type() == type) {
728 return true;
729 }
730 }
731 return false;
732 }
733
734 #ifdef ASSERT
735 int ImmutableOopMap::nr_of_bytes() const {
736 OopMapStream oms(this);
737
738 while (!oms.is_done()) {
739 oms.next();
740 }
741 return sizeof(ImmutableOopMap) + oms.stream_position();
742 }
743 #endif
744
745 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(nullptr), _last(nullptr), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(nullptr) {
746 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
747 }
748
749 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
750 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
751 }
752
753 int ImmutableOopMapBuilder::heap_size() {
754 int base = sizeof(ImmutableOopMapSet);
755 base = align_up(base, 8);
756
757 // all of ours pc / offset pairs
758 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
759 pairs = align_up(pairs, 8);
760
761 for (int i = 0; i < _set->size(); ++i) {
762 int size = 0;
763 OopMap* map = _set->at(i);
764
765 if (is_empty(map)) {
766 /* only keep a single empty map in the set */
767 if (has_empty()) {
768 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
769 } else {
770 _empty_offset = _offset;
771 _empty = map;
772 size = size_for(map);
773 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
774 }
775 } else if (is_last_duplicate(map)) {
776 /* if this entry is identical to the previous one, just point it there */
777 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
778 } else {
779 /* not empty, not an identical copy of the previous entry */
780 size = size_for(map);
781 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
782 _last_offset = _offset;
783 _last = map;
784 }
785
786 assert(_mapping[i]._map == map, "check");
787 _offset += size;
788 }
789
790 int total = base + pairs + _offset;
791 DEBUG_ONLY(total += 8);
792 _required = total;
793 return total;
794 }
795
796 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
797 assert(offset < set->nr_of_bytes(), "check");
798 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
799 }
800
801 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
802 fill_pair(pair, map, offset, set);
803 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
804
805 new (addr) ImmutableOopMap(map);
806 return size_for(map);
807 }
808
809 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
810 ImmutableOopMapPair* pairs = set->get_pairs();
811
812 for (int i = 0; i < set->count(); ++i) {
813 const OopMap* map = _mapping[i]._map;
814 ImmutableOopMapPair* pair = nullptr;
815 int size = 0;
816
817 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
818 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
819 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
820 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
821 }
822
823 //const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
824 //assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
825 }
826 }
827
828 #ifdef ASSERT
829 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
830 for (int i = 0; i < 8; ++i) {
831 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
832 }
833
834 for (int i = 0; i < set->count(); ++i) {
835 const ImmutableOopMapPair* pair = set->pair_at(i);
836 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
837 const ImmutableOopMap* map = pair->get_from(set);
838 int nr_of_bytes = map->nr_of_bytes();
839 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
840 }
841 }
842 #endif
843
844 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
845 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
846
847 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
848 fill(_new_set, _required);
849
850 DEBUG_ONLY(verify(buffer, _required, _new_set));
851
852 return _new_set;
853 }
854
855 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
856 _required = heap_size();
857
858 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
859 address buffer = NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
860 return generate_into(buffer);
861 }
862
863 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
864 ResourceMark mark;
865 ImmutableOopMapBuilder builder(oopmap_set);
866 return builder.build();
867 }
868
869 void ImmutableOopMapSet::operator delete(void* p) {
870 FREE_C_HEAP_ARRAY(unsigned char, p);
871 }
872
873 //------------------------------DerivedPointerTable---------------------------
874
875 #if COMPILER2_OR_JVMCI
876
877 class DerivedPointerTable::Entry : public CHeapObj<mtCompiler> {
878 derived_pointer* _location; // Location of derived pointer, also pointing to base
879 intptr_t _offset; // Offset from base pointer
880 Entry* volatile _next;
881
882 static Entry* volatile* next_ptr(Entry& entry) { return &entry._next; }
883
884 public:
885 Entry(derived_pointer* location, intptr_t offset) :
886 _location(location), _offset(offset), _next(nullptr) {}
887
888 derived_pointer* location() const { return _location; }
889 intptr_t offset() const { return _offset; }
890 Entry* next() const { return _next; }
891
892 typedef LockFreeStack<Entry, &next_ptr> List;
893 static List* _list;
894 };
895
896 DerivedPointerTable::Entry::List* DerivedPointerTable::Entry::_list = nullptr;
897 bool DerivedPointerTable::_active = false;
898
899 bool DerivedPointerTable::is_empty() {
900 return Entry::_list == nullptr || Entry::_list->empty();
901 }
902
903 void DerivedPointerTable::clear() {
904 // The first time, we create the list. Otherwise it should be
905 // empty. If not, then we have probably forgotton to call
906 // update_pointers after last GC/Scavenge.
907 assert (!_active, "should not be active");
908 assert(is_empty(), "table not empty");
909 if (Entry::_list == nullptr) {
910 void* mem = NEW_C_HEAP_OBJ(Entry::List, mtCompiler);
911 Entry::_list = ::new (mem) Entry::List();
912 }
913 _active = true;
914 }
915
916 void DerivedPointerTable::add(derived_pointer* derived_loc, derived_base* base_loc) {
917 assert(Universe::heap()->is_in_or_null((void*)*base_loc), "not an oop");
918 assert(derived_loc != (void*)base_loc, "Base and derived in same location");
919 derived_pointer base_loc_as_derived_pointer =
920 static_cast<derived_pointer>(reinterpret_cast<intptr_t>(base_loc));
921 assert(*derived_loc != base_loc_as_derived_pointer, "location already added");
922 assert(Entry::_list != nullptr, "list must exist");
923 assert(is_active(), "table must be active here");
924 intptr_t offset = *derived_loc - to_derived_pointer(*reinterpret_cast<intptr_t*>(base_loc));
925 // This assert is invalid because derived pointers can be
926 // arbitrarily far away from their base.
927 // assert(offset >= -1000000, "wrong derived pointer info");
928
929 if (TraceDerivedPointers) {
930 tty->print_cr(
931 "Add derived pointer@" INTPTR_FORMAT
932 " - Derived: " INTPTR_FORMAT
933 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
934 p2i(derived_loc), derived_pointer_value(*derived_loc), intptr_t(*base_loc), p2i(base_loc), offset
935 );
936 }
937 // Set derived oop location to point to base.
938 *derived_loc = base_loc_as_derived_pointer;
939 Entry* entry = new Entry(derived_loc, offset);
940 Entry::_list->push(*entry);
941 }
942
943 void DerivedPointerTable::update_pointers() {
944 assert(Entry::_list != nullptr, "list must exist");
945 Entry* entries = Entry::_list->pop_all();
946 while (entries != nullptr) {
947 Entry* entry = entries;
948 entries = entry->next();
949 derived_pointer* derived_loc = entry->location();
950 intptr_t offset = entry->offset();
951 // The derived oop was setup to point to location of base
952 oop base = **reinterpret_cast<oop**>(derived_loc);
953 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
954
955 derived_pointer derived_base = to_derived_pointer(cast_from_oop<intptr_t>(base));
956 *derived_loc = derived_base + offset;
957 assert(*derived_loc - derived_base == offset, "sanity check");
958
959 // 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);
960
961 if (TraceDerivedPointers) {
962 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
963 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
964 p2i(derived_loc), derived_pointer_value(*derived_loc), p2i(base), offset);
965 }
966
967 // Delete entry
968 delete entry;
969 }
970 assert(Entry::_list->empty(), "invariant");
971 _active = false;
972 }
973
974 #endif // COMPILER2_OR_JVMCI