1 /*
2 * Copyright (c) 1998, 2021, 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.hpp"
31 #include "gc/shared/collectedHeap.hpp"
32 #include "memory/allocation.inline.hpp"
33 #include "memory/iterator.hpp"
34 #include "memory/resourceArea.hpp"
35 #include "memory/universe.hpp"
36 #include "oops/inlineKlass.hpp"
37 #include "oops/compressedOops.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(oop obj) {
61 return static_cast<derived_pointer>(cast_from_oop<intptr_t>(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(OopMap* oop_map) {
75 _stream = new CompressedReadStream(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 = new CompressedReadStream(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
107 #ifdef ASSERT
108 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
109 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
110 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
111 #endif
112 }
113
114
115 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
116 // This constructor does a deep copy
117 // of the source OopMap.
118 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
119 set_omv_count(0);
120 set_offset(source->offset());
121
122 #ifdef ASSERT
123 _locs_length = source->_locs_length;
124 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
125 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
126 #endif
127
128 // We need to copy the entries too.
129 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
130 OopMapValue omv = oms.current();
131 omv.write_on(write_stream());
132 increment_count();
133 }
134 }
135
136
137 OopMap* OopMap::deep_copy() {
138 return new OopMap(_deep_copy_token, this);
139 }
140
141 void OopMap::copy_data_to(address addr) const {
142 memcpy(addr, write_stream()->buffer(), write_stream()->position());
143 }
144
145 int OopMap::heap_size() const {
146 int size = sizeof(OopMap);
147 int align = sizeof(void *) - 1;
148 size += write_stream()->position();
149 // Align to a reasonable ending point
150 size = ((size+align) & ~align);
151 return size;
152 }
153
154 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
155 // slots to hold 4-byte values like ints and floats in the LP64 build.
156 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
157
158 assert(reg->value() < _locs_length, "too big reg value for stack size");
159 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
160 debug_only( _locs_used[reg->value()] = x; )
161
162 OopMapValue o(reg, x, optional);
163 o.write_on(write_stream());
164 increment_count();
165 }
166
167
168 void OopMap::set_oop(VMReg reg) {
169 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
170 }
171
172
173 void OopMap::set_narrowoop(VMReg reg) {
174 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
175 }
176
177
178 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
179 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
180 }
181
182
183 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
184 if( reg == derived_from_local_register ) {
185 // Actually an oop, derived shares storage with base,
186 set_oop(reg);
187 } else {
188 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
189 }
190 }
191
192 // OopMapSet
193
194 OopMapSet::OopMapSet() : _list(MinOopMapAllocation) {}
195
196 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
197 map->set_offset(pc_offset);
198
199 #ifdef ASSERT
200 if(_list.length() > 0) {
201 OopMap* last = _list.last();
202 if (last->offset() == map->offset() ) {
203 fatal("OopMap inserted twice");
204 }
205 if (last->offset() > map->offset()) {
206 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
207 _list.length(),last->offset(),_list.length()+1,map->offset());
208 }
209 }
210 #endif // ASSERT
211
212 add(map);
213 }
214
215 static void add_derived_oop(oop* base, derived_pointer* derived, OopClosure* oop_fn) {
216 #if COMPILER2_OR_JVMCI
217 DerivedPointerTable::add(derived, base);
218 #endif // COMPILER2_OR_JVMCI
219 }
220
221 static void ignore_derived_oop(oop* base, derived_pointer* derived, OopClosure* oop_fn) {
222 }
223
224 static void process_derived_oop(oop* base, derived_pointer* derived, OopClosure* oop_fn) {
225 // All derived pointers must be processed before the base pointer of any derived pointer is processed.
226 // Otherwise, if two derived pointers use the same base, the second derived pointer will get an obscured
227 // offset, if the base pointer is processed in the first derived pointer.
228 derived_pointer derived_base = to_derived_pointer(*base);
229 intptr_t offset = *derived - derived_base;
230 *derived = derived_base;
231 oop_fn->do_oop((oop*)derived);
232 *derived = *derived + offset;
233 }
234
235
236 #ifndef PRODUCT
237 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
238 // Print oopmap and regmap
239 tty->print_cr("------ ");
240 CodeBlob* cb = fr->cb();
241 const ImmutableOopMapSet* maps = cb->oop_maps();
242 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
243 map->print();
244 if( cb->is_nmethod() ) {
245 nmethod* nm = (nmethod*)cb;
246 // native wrappers have no scope data, it is implied
247 if (nm->is_native_method()) {
248 tty->print("bci: 0 (native)");
249 } else {
250 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
251 tty->print("bci: %d ",scope->bci());
252 }
253 }
254 tty->cr();
255 fr->print_on(tty);
256 tty->print(" ");
257 cb->print_value_on(tty); tty->cr();
258 reg_map->print();
259 tty->print_cr("------ ");
260
261 }
262 #endif // PRODUCT
263
264 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f, DerivedPointerIterationMode mode) {
265 switch (mode) {
266 case DerivedPointerIterationMode::_directly:
267 all_do(fr, reg_map, f, process_derived_oop);
268 break;
269 case DerivedPointerIterationMode::_with_table:
270 all_do(fr, reg_map, f, add_derived_oop);
271 break;
272 case DerivedPointerIterationMode::_ignore:
273 all_do(fr, reg_map, f, ignore_derived_oop);
274 break;
275 }
276 }
277
278
279 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
280 OopClosure* oop_fn, void derived_oop_fn(oop*, derived_pointer*, OopClosure*)) {
281 CodeBlob* cb = fr->cb();
282 assert(cb != NULL, "no codeblob");
283
284 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
285
286 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
287 assert(map != NULL, "no ptr map found");
288
289 // handle derived pointers first (otherwise base pointer may be
290 // changed before derived pointer offset has been collected)
291 {
292 for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
293 OopMapValue omv = oms.current();
294 if (omv.type() != OopMapValue::derived_oop_value) {
295 continue;
296 }
297
298 #ifndef COMPILER2
299 COMPILER1_PRESENT(ShouldNotReachHere();)
300 #if INCLUDE_JVMCI
301 if (UseJVMCICompiler) {
302 ShouldNotReachHere();
303 }
304 #endif
305 #endif // !COMPILER2
306 derived_pointer* derived_loc = (derived_pointer*)fr->oopmapreg_to_location(omv.reg(),reg_map);
307 guarantee(derived_loc != NULL, "missing saved register");
308 oop* base_loc = fr->oopmapreg_to_oop_location(omv.content_reg(), reg_map);
309 // Ignore NULL oops and decoded NULL narrow oops which
310 // equal to CompressedOops::base() when a narrow oop
311 // implicit null check is used in compiled code.
312 // The narrow_oop_base could be NULL or be the address
313 // of the page below heap depending on compressed oops mode.
314 if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
315 derived_oop_fn(base_loc, derived_loc, oop_fn);
316 }
317 }
318 }
319
320 {
321 // We want coop and oop oop_types
322 for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
323 OopMapValue omv = oms.current();
324 oop* loc = fr->oopmapreg_to_oop_location(omv.reg(),reg_map);
325 // It should be an error if no location can be found for a
326 // register mentioned as contained an oop of some kind. Maybe
327 // this was allowed previously because value_value items might
328 // be missing?
329 guarantee(loc != NULL, "missing saved register");
330 if ( omv.type() == OopMapValue::oop_value ) {
331 oop val = *loc;
332 if (val == NULL || CompressedOops::is_base(val)) {
333 // Ignore NULL oops and decoded NULL narrow oops which
334 // equal to CompressedOops::base() when a narrow oop
335 // implicit null check is used in compiled code.
336 // The narrow_oop_base could be NULL or be the address
337 // of the page below heap depending on compressed oops mode.
338 continue;
339 }
340 oop_fn->do_oop(loc);
341 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
342 narrowOop *nl = (narrowOop*)loc;
343 #ifndef VM_LITTLE_ENDIAN
344 VMReg vmReg = omv.reg();
345 if (!vmReg->is_stack()) {
346 // compressed oops in registers only take up 4 bytes of an
347 // 8 byte register but they are in the wrong part of the
348 // word so adjust loc to point at the right place.
349 nl = (narrowOop*)((address)nl + 4);
350 }
351 #endif
352 oop_fn->do_oop(nl);
353 }
354 }
355 }
356 }
357
358
359 // Update callee-saved register info for the following frame
360 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
361 ResourceMark rm;
362 CodeBlob* cb = fr->cb();
363 assert(cb != NULL, "no codeblob");
364
365 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
366 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
367 "already updated this map; do not 'update' it twice!" );
368 debug_only(reg_map->_update_for_id = fr->id());
369
370 // Check if caller must update oop argument
371 assert((reg_map->include_argument_oops() ||
372 !cb->caller_must_gc_arguments(reg_map->thread())),
373 "include_argument_oops should already be set");
374
375 // Scan through oopmap and find location of all callee-saved registers
376 // (we do not do update in place, since info could be overwritten)
377
378 address pc = fr->pc();
379 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
380 assert(map != NULL, "no ptr map found");
381 DEBUG_ONLY(int nof_callee = 0;)
382
383 for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
384 OopMapValue omv = oms.current();
385 if (omv.type() == OopMapValue::callee_saved_value) {
386 VMReg reg = omv.content_reg();
387 oop* loc = fr->oopmapreg_to_oop_location(omv.reg(), reg_map);
388 reg_map->set_location(reg, (address) loc);
389 DEBUG_ONLY(nof_callee++;)
390 }
391 }
392
393 // Check that runtime stubs save all callee-saved registers
394 #ifdef COMPILER2
395 assert(cb->is_compiled_by_c1() || cb->is_compiled_by_jvmci() || !cb->is_runtime_stub() ||
396 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
397 "must save all");
398 #endif // COMPILER2
399 }
400
401 // Printing code is present in product build for -XX:+PrintAssembly.
402
403 static
404 void print_register_type(OopMapValue::oop_types x, VMReg optional,
405 outputStream* st) {
406 switch( x ) {
407 case OopMapValue::oop_value:
408 st->print("Oop");
409 break;
410 case OopMapValue::narrowoop_value:
411 st->print("NarrowOop");
412 break;
413 case OopMapValue::callee_saved_value:
414 st->print("Callers_");
415 optional->print_on(st);
416 break;
417 case OopMapValue::derived_oop_value:
418 st->print("Derived_oop_");
419 optional->print_on(st);
420 break;
421 default:
422 ShouldNotReachHere();
423 }
424 }
425
426 void OopMapValue::print_on(outputStream* st) const {
427 reg()->print_on(st);
428 st->print("=");
429 print_register_type(type(),content_reg(),st);
430 st->print(" ");
431 }
432
433 void OopMapValue::print() const { print_on(tty); }
434
435 void ImmutableOopMap::print_on(outputStream* st) const {
436 OopMapValue omv;
437 st->print("ImmutableOopMap {");
438 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
439 omv = oms.current();
440 omv.print_on(st);
441 }
442 st->print("}");
443 }
444
445 void ImmutableOopMap::print() const { print_on(tty); }
446
447 void OopMap::print_on(outputStream* st) const {
448 OopMapValue omv;
449 st->print("OopMap {");
450 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
451 omv = oms.current();
452 omv.print_on(st);
453 }
454 // Print hex offset in addition.
455 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
456 }
457
458 void OopMap::print() const { print_on(tty); }
459
460 void ImmutableOopMapSet::print_on(outputStream* st) const {
461 const ImmutableOopMap* last = NULL;
462 const int len = count();
463
464 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
465
466 for (int i = 0; i < len; i++) {
467 const ImmutableOopMapPair* pair = pair_at(i);
468 const ImmutableOopMap* map = pair->get_from(this);
469 if (map != last) {
470 st->cr();
471 map->print_on(st);
472 st->print(" pc offsets: ");
473 }
474 last = map;
475 st->print("%d ", pair->pc_offset());
476 }
477 st->cr();
478 }
479
480 void ImmutableOopMapSet::print() const { print_on(tty); }
481
482 void OopMapSet::print_on(outputStream* st) const {
483 const int len = _list.length();
484
485 st->print_cr("OopMapSet contains %d OopMaps", len);
486
487 for( int i = 0; i < len; i++) {
488 OopMap* m = at(i);
489 st->print_cr("#%d ",i);
490 m->print_on(st);
491 st->cr();
492 }
493 st->cr();
494 }
495
496 void OopMapSet::print() const { print_on(tty); }
497
498 bool OopMap::equals(const OopMap* other) const {
499 if (other->_omv_count != _omv_count) {
500 return false;
501 }
502 if (other->write_stream()->position() != write_stream()->position()) {
503 return false;
504 }
505 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
506 return false;
507 }
508 return true;
509 }
510
511 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
512 ImmutableOopMapPair* pairs = get_pairs();
513 ImmutableOopMapPair* last = NULL;
514
515 for (int i = 0; i < _count; ++i) {
516 if (pairs[i].pc_offset() >= pc_offset) {
517 last = &pairs[i];
518 break;
519 }
520 }
521
522 // Heal Coverity issue: potential index out of bounds access.
523 guarantee(last != NULL, "last may not be null");
524 assert(last->pc_offset() == pc_offset, "oopmap not found");
525 return last->get_from(this);
526 }
527
528 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
529 return set->oopmap_at_offset(_oopmap_offset);
530 }
531
532 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
533 address addr = data_addr();
534 oopmap->copy_data_to(addr);
535 }
536
537 #ifdef ASSERT
538 int ImmutableOopMap::nr_of_bytes() const {
539 OopMapStream oms(this);
540
541 while (!oms.is_done()) {
542 oms.next();
543 }
544 return sizeof(ImmutableOopMap) + oms.stream_position();
545 }
546 #endif
547
548 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(NULL) {
549 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
550 }
551
552 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
553 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
554 }
555
556 int ImmutableOopMapBuilder::heap_size() {
557 int base = sizeof(ImmutableOopMapSet);
558 base = align_up(base, 8);
559
560 // all of ours pc / offset pairs
561 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
562 pairs = align_up(pairs, 8);
563
564 for (int i = 0; i < _set->size(); ++i) {
565 int size = 0;
566 OopMap* map = _set->at(i);
567
568 if (is_empty(map)) {
569 /* only keep a single empty map in the set */
570 if (has_empty()) {
571 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
572 } else {
573 _empty_offset = _offset;
574 _empty = map;
575 size = size_for(map);
576 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
577 }
578 } else if (is_last_duplicate(map)) {
579 /* if this entry is identical to the previous one, just point it there */
580 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
581 } else {
582 /* not empty, not an identical copy of the previous entry */
583 size = size_for(map);
584 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
585 _last_offset = _offset;
586 _last = map;
587 }
588
589 assert(_mapping[i]._map == map, "check");
590 _offset += size;
591 }
592
593 int total = base + pairs + _offset;
594 DEBUG_ONLY(total += 8);
595 _required = total;
596 return total;
597 }
598
599 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
600 assert(offset < set->nr_of_bytes(), "check");
601 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
602 }
603
604 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
605 fill_pair(pair, map, offset, set);
606 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
607
608 new (addr) ImmutableOopMap(map);
609 return size_for(map);
610 }
611
612 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
613 ImmutableOopMapPair* pairs = set->get_pairs();
614
615 for (int i = 0; i < set->count(); ++i) {
616 const OopMap* map = _mapping[i]._map;
617 ImmutableOopMapPair* pair = NULL;
618 int size = 0;
619
620 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
621 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
622 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
623 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
624 }
625
626 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
627 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
628 }
629 }
630
631 #ifdef ASSERT
632 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
633 for (int i = 0; i < 8; ++i) {
634 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
635 }
636
637 for (int i = 0; i < set->count(); ++i) {
638 const ImmutableOopMapPair* pair = set->pair_at(i);
639 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
640 const ImmutableOopMap* map = pair->get_from(set);
641 int nr_of_bytes = map->nr_of_bytes();
642 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
643 }
644 }
645 #endif
646
647 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
648 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
649
650 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
651 fill(_new_set, _required);
652
653 DEBUG_ONLY(verify(buffer, _required, _new_set));
654
655 return _new_set;
656 }
657
658 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
659 _required = heap_size();
660
661 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
662 address buffer = NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
663 return generate_into(buffer);
664 }
665
666 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
667 ResourceMark mark;
668 ImmutableOopMapBuilder builder(oopmap_set);
669 return builder.build();
670 }
671
672
673 //------------------------------DerivedPointerTable---------------------------
674
675 #if COMPILER2_OR_JVMCI
676
677 class DerivedPointerTable::Entry : public CHeapObj<mtCompiler> {
678 derived_pointer* _location; // Location of derived pointer, also pointing to base
679 intptr_t _offset; // Offset from base pointer
680 Entry* volatile _next;
681
682 static Entry* volatile* next_ptr(Entry& entry) { return &entry._next; }
683
684 public:
685 Entry(derived_pointer* location, intptr_t offset) :
686 _location(location), _offset(offset), _next(NULL) {}
687
688 derived_pointer* location() const { return _location; }
689 intptr_t offset() const { return _offset; }
690 Entry* next() const { return _next; }
691
692 typedef LockFreeStack<Entry, &next_ptr> List;
693 static List* _list;
694 };
695
696 DerivedPointerTable::Entry::List* DerivedPointerTable::Entry::_list = NULL;
697 bool DerivedPointerTable::_active = false;
698
699 bool DerivedPointerTable::is_empty() {
700 return Entry::_list == NULL || Entry::_list->empty();
701 }
702
703 void DerivedPointerTable::clear() {
704 // The first time, we create the list. Otherwise it should be
705 // empty. If not, then we have probably forgotton to call
706 // update_pointers after last GC/Scavenge.
707 assert (!_active, "should not be active");
708 assert(is_empty(), "table not empty");
709 if (Entry::_list == NULL) {
710 void* mem = NEW_C_HEAP_OBJ(Entry::List, mtCompiler);
711 Entry::_list = ::new (mem) Entry::List();
712 }
713 _active = true;
714 }
715
716 void DerivedPointerTable::add(derived_pointer* derived_loc, oop *base_loc) {
717 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
718 assert(derived_loc != (void*)base_loc, "Base and derived in same location");
719 derived_pointer base_loc_as_derived_pointer =
720 static_cast<derived_pointer>(reinterpret_cast<intptr_t>(base_loc));
721 assert(*derived_loc != base_loc_as_derived_pointer, "location already added");
722 assert(Entry::_list != NULL, "list must exist");
723 assert(is_active(), "table must be active here");
724 intptr_t offset = *derived_loc - to_derived_pointer(*base_loc);
725 // This assert is invalid because derived pointers can be
726 // arbitrarily far away from their base.
727 // assert(offset >= -1000000, "wrong derived pointer info");
728
729 if (TraceDerivedPointers) {
730 tty->print_cr(
731 "Add derived pointer@" INTPTR_FORMAT
732 " - Derived: " INTPTR_FORMAT
733 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
734 p2i(derived_loc), derived_pointer_value(*derived_loc), p2i(*base_loc), p2i(base_loc), offset
735 );
736 }
737 // Set derived oop location to point to base.
738 *derived_loc = base_loc_as_derived_pointer;
739 Entry* entry = new Entry(derived_loc, offset);
740 Entry::_list->push(*entry);
741 }
742
743 void DerivedPointerTable::update_pointers() {
744 assert(Entry::_list != NULL, "list must exist");
745 Entry* entries = Entry::_list->pop_all();
746 while (entries != NULL) {
747 Entry* entry = entries;
748 entries = entry->next();
749 derived_pointer* derived_loc = entry->location();
750 intptr_t offset = entry->offset();
751 // The derived oop was setup to point to location of base
752 oop base = **reinterpret_cast<oop**>(derived_loc);
753 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
754
755 derived_pointer derived_base = to_derived_pointer(base);
756 *derived_loc = derived_base + offset;
757 assert(*derived_loc - derived_base == offset, "sanity check");
758
759 if (TraceDerivedPointers) {
760 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
761 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
762 p2i(derived_loc), derived_pointer_value(*derived_loc), p2i(base), offset);
763 }
764
765 // Delete entry
766 delete entry;
767 }
768 assert(Entry::_list->empty(), "invariant");
769 _active = false;
770 }
771
772 #endif // COMPILER2_OR_JVMCI