1 /*
2 * Copyright (c) 1998, 2019, 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/compressedOops.hpp"
37 #include "runtime/frame.inline.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/signature.hpp"
40 #include "utilities/align.hpp"
41 #include "utilities/lockFreeStack.hpp"
42 #ifdef COMPILER1
43 #include "c1/c1_Defs.hpp"
44 #endif
45 #ifdef COMPILER2
46 #include "opto/optoreg.hpp"
47 #endif
48
49 // OopMapStream
50
51 OopMapStream::OopMapStream(OopMap* oop_map) {
52 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
53 _size = oop_map->omv_count();
54 _position = 0;
55 _valid_omv = false;
56 }
57
58 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map) {
59 _stream = new CompressedReadStream(oop_map->data_addr());
60 _size = oop_map->count();
61 _position = 0;
62 _valid_omv = false;
63 }
64
65 void OopMapStream::find_next() {
66 if (_position++ < _size) {
67 _omv.read_from(_stream);
68 _valid_omv = true;
69 return;
70 }
71 _valid_omv = false;
72 }
73
74
75 // OopMap
76
77 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
78 // slots to hold 4-byte values like ints and floats in the LP64 build.
79 OopMap::OopMap(int frame_size, int arg_count) {
80 // OopMaps are usually quite so small, so pick a small initial size
81 set_write_stream(new CompressedWriteStream(32));
82 set_omv_count(0);
83
84 #ifdef ASSERT
85 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
86 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
87 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
88 #endif
89 }
90
91
92 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
93 // This constructor does a deep copy
94 // of the source OopMap.
95 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
96 set_omv_count(0);
97 set_offset(source->offset());
98
99 #ifdef ASSERT
100 _locs_length = source->_locs_length;
101 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
102 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
103 #endif
104
105 // We need to copy the entries too.
106 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
107 OopMapValue omv = oms.current();
108 omv.write_on(write_stream());
109 increment_count();
110 }
111 }
112
113
114 OopMap* OopMap::deep_copy() {
115 return new OopMap(_deep_copy_token, this);
116 }
117
118 void OopMap::copy_data_to(address addr) const {
119 memcpy(addr, write_stream()->buffer(), write_stream()->position());
120 }
121
122 int OopMap::heap_size() const {
123 int size = sizeof(OopMap);
124 int align = sizeof(void *) - 1;
125 size += write_stream()->position();
126 // Align to a reasonable ending point
127 size = ((size+align) & ~align);
128 return size;
129 }
130
131 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
132 // slots to hold 4-byte values like ints and floats in the LP64 build.
133 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
134
135 assert(reg->value() < _locs_length, "too big reg value for stack size");
136 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
137 debug_only( _locs_used[reg->value()] = x; )
138
139 OopMapValue o(reg, x, optional);
140 o.write_on(write_stream());
141 increment_count();
142 }
143
144
145 void OopMap::set_oop(VMReg reg) {
146 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
147 }
148
149
150 void OopMap::set_narrowoop(VMReg reg) {
151 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
152 }
153
154
155 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
156 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
157 }
158
159
160 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
161 if( reg == derived_from_local_register ) {
162 // Actually an oop, derived shares storage with base,
163 set_oop(reg);
164 } else {
165 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
166 }
167 }
168
169 // OopMapSet
170
171 OopMapSet::OopMapSet() {
172 set_om_size(MinOopMapAllocation);
173 set_om_count(0);
174 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
175 set_om_data(temp);
176 }
177
178
179 void OopMapSet::grow_om_data() {
180 int new_size = om_size() * 2;
181 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
182 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
183 set_om_size(new_size);
184 set_om_data(new_data);
185 }
186
187 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
188 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
189
190 if(om_count() >= om_size()) {
191 grow_om_data();
192 }
193 map->set_offset(pc_offset);
194
195 #ifdef ASSERT
196 if(om_count() > 0) {
197 OopMap* last = at(om_count()-1);
198 if (last->offset() == map->offset() ) {
199 fatal("OopMap inserted twice");
200 }
201 if(last->offset() > map->offset()) {
202 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
203 om_count(),last->offset(),om_count()+1,map->offset());
204 }
205 }
206 #endif // ASSERT
207
208 set(om_count(),map);
209 increment_count();
210 }
211
212
213 int OopMapSet::heap_size() const {
214 // The space we use
215 int size = sizeof(OopMap);
216 int align = sizeof(void *) - 1;
217 size = ((size+align) & ~align);
218 size += om_count() * sizeof(OopMap*);
219
220 // Now add in the space needed for the indivdiual OopMaps
221 for(int i=0; i < om_count(); i++) {
222 size += at(i)->heap_size();
223 }
224 // We don't need to align this, it will be naturally pointer aligned
225 return size;
226 }
227
228
229 OopMap* OopMapSet::singular_oop_map() {
230 guarantee(om_count() == 1, "Make sure we only have a single gc point");
231 return at(0);
232 }
233
234
235 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
236 int i, len = om_count();
237 assert( len > 0, "must have pointer maps" );
238
239 // Scan through oopmaps. Stop when current offset is either equal or greater
240 // than the one we are looking for.
241 for( i = 0; i < len; i++) {
242 if( at(i)->offset() >= pc_offset )
243 break;
244 }
245
246 assert( i < len, "oopmap not found" );
247
248 OopMap* m = at(i);
249 assert( m->offset() == pc_offset, "oopmap not found" );
250 return m;
251 }
252
253 static void add_derived_oop(oop* base, oop* derived) {
254 #if !defined(TIERED) && !INCLUDE_JVMCI
255 COMPILER1_PRESENT(ShouldNotReachHere();)
256 #endif // !defined(TIERED) && !INCLUDE_JVMCI
257 #if COMPILER2_OR_JVMCI
258 DerivedPointerTable::add(derived, base);
259 #endif // COMPILER2_OR_JVMCI
260 }
261
262
263 #ifndef PRODUCT
264 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
265 // Print oopmap and regmap
266 tty->print_cr("------ ");
267 CodeBlob* cb = fr->cb();
268 const ImmutableOopMapSet* maps = cb->oop_maps();
269 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
270 map->print();
271 if( cb->is_nmethod() ) {
272 nmethod* nm = (nmethod*)cb;
273 // native wrappers have no scope data, it is implied
274 if (nm->is_native_method()) {
275 tty->print("bci: 0 (native)");
276 } else {
277 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
278 tty->print("bci: %d ",scope->bci());
279 }
280 }
281 tty->cr();
282 fr->print_on(tty);
283 tty->print(" ");
284 cb->print_value_on(tty); tty->cr();
285 reg_map->print();
286 tty->print_cr("------ ");
287
288 }
289 #endif // PRODUCT
290
291 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
292 // add derived oops to a table
293 all_do(fr, reg_map, f, add_derived_oop, &do_nothing_cl);
294 }
295
296
297 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
298 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
299 OopClosure* value_fn) {
300 CodeBlob* cb = fr->cb();
301 assert(cb != NULL, "no codeblob");
302
303 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
304
305 const ImmutableOopMapSet* maps = cb->oop_maps();
306 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
307 assert(map != NULL, "no ptr map found");
308
309 // handle derived pointers first (otherwise base pointer may be
310 // changed before derived pointer offset has been collected)
311 OopMapValue omv;
312 {
313 OopMapStream oms(map);
314 if (!oms.is_done()) {
315 #ifndef TIERED
316 omv = oms.current();
317 bool is_derived_oop = omv.type() == OopMapValue::derived_oop_value;
318 COMPILER1_PRESENT(if (is_derived_oop) ShouldNotReachHere();)
319 #if INCLUDE_JVMCI
320 if (UseJVMCICompiler) {
321 if (is_derived_oop) ShouldNotReachHere();
322 }
323 #endif
324 #endif // !TIERED
325 do {
326 omv = oms.current();
327 if (omv.type() == OopMapValue::derived_oop_value) {
328 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
329 guarantee(loc != NULL, "missing saved register");
330 oop *derived_loc = loc;
331 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
332 // Ignore NULL oops and decoded NULL narrow oops which
333 // equal to CompressedOops::base() when a narrow oop
334 // implicit null check is used in compiled code.
335 // The narrow_oop_base could be NULL or be the address
336 // of the page below heap depending on compressed oops mode.
337 if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
338 derived_oop_fn(base_loc, derived_loc);
339 }
340 }
341 oms.next();
342 } while (!oms.is_done());
343 }
344 }
345
346 {
347 // We want coop and oop oop_types
348 for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
349 omv = oms.current();
350 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
351 // It should be an error if no location can be found for a
352 // register mentioned as contained an oop of some kind. Maybe
353 // this was allowed previously because value_value items might
354 // be missing?
355 guarantee(loc != NULL, "missing saved register");
356 if ( omv.type() == OopMapValue::oop_value ) {
357 oop val = *loc;
358 if (val == NULL || CompressedOops::is_base(val)) {
359 // Ignore NULL oops and decoded NULL narrow oops which
360 // equal to CompressedOops::base() when a narrow oop
361 // implicit null check is used in compiled code.
362 // The narrow_oop_base could be NULL or be the address
363 // of the page below heap depending on compressed oops mode.
364 continue;
365 }
366 #ifdef ASSERT
367 if ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) ||
368 !Universe::heap()->is_in_or_null(*loc)) {
369 tty->print_cr("# Found non oop pointer. Dumping state at failure");
370 // try to dump out some helpful debugging information
371 trace_codeblob_maps(fr, reg_map);
372 omv.print();
373 tty->print_cr("register r");
374 omv.reg()->print();
375 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
376 // do the real assert.
377 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
378 }
379 #endif // ASSERT
380 oop_fn->do_oop(loc);
381 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
382 narrowOop *nl = (narrowOop*)loc;
383 #ifndef VM_LITTLE_ENDIAN
384 VMReg vmReg = omv.reg();
385 // Don't do this on SPARC float registers as they can be individually addressed
386 if (!vmReg->is_stack() SPARC_ONLY(&& !vmReg->is_FloatRegister())) {
387 // compressed oops in registers only take up 4 bytes of an
388 // 8 byte register but they are in the wrong part of the
389 // word so adjust loc to point at the right place.
390 nl = (narrowOop*)((address)nl + 4);
391 }
392 #endif
393 oop_fn->do_oop(nl);
394 }
395 }
396 }
397 }
398
399
400 // Update callee-saved register info for the following frame
401 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
402 ResourceMark rm;
403 CodeBlob* cb = fr->cb();
404 assert(cb != NULL, "no codeblob");
405
406 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
407 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
408 "already updated this map; do not 'update' it twice!" );
409 debug_only(reg_map->_update_for_id = fr->id());
410
411 // Check if caller must update oop argument
412 assert((reg_map->include_argument_oops() ||
413 !cb->caller_must_gc_arguments(reg_map->thread())),
414 "include_argument_oops should already be set");
415
416 // Scan through oopmap and find location of all callee-saved registers
417 // (we do not do update in place, since info could be overwritten)
418
419 address pc = fr->pc();
420 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
421 assert(map != NULL, "no ptr map found");
422 DEBUG_ONLY(int nof_callee = 0;)
423
424 for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
425 OopMapValue omv = oms.current();
426 if (omv.type() == OopMapValue::callee_saved_value) {
427 VMReg reg = omv.content_reg();
428 oop* loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
429 reg_map->set_location(reg, (address) loc);
430 DEBUG_ONLY(nof_callee++;)
431 }
432 }
433
434 // Check that runtime stubs save all callee-saved registers
435 #ifdef COMPILER2
436 assert(cb->is_compiled_by_c1() || cb->is_compiled_by_jvmci() || !cb->is_runtime_stub() ||
437 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
438 "must save all");
439 #endif // COMPILER2
440 }
441
442 // Printing code is present in product build for -XX:+PrintAssembly.
443
444 static
445 void print_register_type(OopMapValue::oop_types x, VMReg optional,
446 outputStream* st) {
447 switch( x ) {
448 case OopMapValue::oop_value:
449 st->print("Oop");
450 break;
451 case OopMapValue::narrowoop_value:
452 st->print("NarrowOop");
453 break;
454 case OopMapValue::callee_saved_value:
455 st->print("Callers_");
456 optional->print_on(st);
457 break;
458 case OopMapValue::derived_oop_value:
459 st->print("Derived_oop_");
460 optional->print_on(st);
461 break;
462 default:
463 ShouldNotReachHere();
464 }
465 }
466
467 void OopMapValue::print_on(outputStream* st) const {
468 reg()->print_on(st);
469 st->print("=");
470 print_register_type(type(),content_reg(),st);
471 st->print(" ");
472 }
473
474 void OopMapValue::print() const { print_on(tty); }
475
476 void ImmutableOopMap::print_on(outputStream* st) const {
477 OopMapValue omv;
478 st->print("ImmutableOopMap {");
479 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
480 omv = oms.current();
481 omv.print_on(st);
482 }
483 st->print("}");
484 }
485
486 void ImmutableOopMap::print() const { print_on(tty); }
487
488 void OopMap::print_on(outputStream* st) const {
489 OopMapValue omv;
490 st->print("OopMap {");
491 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
492 omv = oms.current();
493 omv.print_on(st);
494 }
495 // Print hex offset in addition.
496 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
497 }
498
499 void OopMap::print() const { print_on(tty); }
500
501 void ImmutableOopMapSet::print_on(outputStream* st) const {
502 const ImmutableOopMap* last = NULL;
503 const int len = count();
504
505 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
506
507 for (int i = 0; i < len; i++) {
508 const ImmutableOopMapPair* pair = pair_at(i);
509 const ImmutableOopMap* map = pair->get_from(this);
510 if (map != last) {
511 st->cr();
512 map->print_on(st);
513 st->print(" pc offsets: ");
514 }
515 last = map;
516 st->print("%d ", pair->pc_offset());
517 }
518 st->cr();
519 }
520
521 void ImmutableOopMapSet::print() const { print_on(tty); }
522
523 void OopMapSet::print_on(outputStream* st) const {
524 const int len = om_count();
525
526 st->print_cr("OopMapSet contains %d OopMaps", len);
527
528 for( int i = 0; i < len; i++) {
529 OopMap* m = at(i);
530 st->print_cr("#%d ",i);
531 m->print_on(st);
532 st->cr();
533 }
534 st->cr();
535 }
536
537 void OopMapSet::print() const { print_on(tty); }
538
539 bool OopMap::equals(const OopMap* other) const {
540 if (other->_omv_count != _omv_count) {
541 return false;
542 }
543 if (other->write_stream()->position() != write_stream()->position()) {
544 return false;
545 }
546 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
547 return false;
548 }
549 return true;
550 }
551
552 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
553 ImmutableOopMapPair* pairs = get_pairs();
554 ImmutableOopMapPair* last = NULL;
555
556 for (int i = 0; i < _count; ++i) {
557 if (pairs[i].pc_offset() >= pc_offset) {
558 last = &pairs[i];
559 break;
560 }
561 }
562
563 // Heal Coverity issue: potential index out of bounds access.
564 guarantee(last != NULL, "last may not be null");
565 assert(last->pc_offset() == pc_offset, "oopmap not found");
566 return last->get_from(this);
567 }
568
569 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
570 return set->oopmap_at_offset(_oopmap_offset);
571 }
572
573 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
574 address addr = data_addr();
575 oopmap->copy_data_to(addr);
576 }
577
578 #ifdef ASSERT
579 int ImmutableOopMap::nr_of_bytes() const {
580 OopMapStream oms(this);
581
582 while (!oms.is_done()) {
583 oms.next();
584 }
585 return sizeof(ImmutableOopMap) + oms.stream_position();
586 }
587 #endif
588
589 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(NULL) {
590 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
591 }
592
593 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
594 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
595 }
596
597 int ImmutableOopMapBuilder::heap_size() {
598 int base = sizeof(ImmutableOopMapSet);
599 base = align_up(base, 8);
600
601 // all of ours pc / offset pairs
602 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
603 pairs = align_up(pairs, 8);
604
605 for (int i = 0; i < _set->size(); ++i) {
606 int size = 0;
607 OopMap* map = _set->at(i);
608
609 if (is_empty(map)) {
610 /* only keep a single empty map in the set */
611 if (has_empty()) {
612 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
613 } else {
614 _empty_offset = _offset;
615 _empty = map;
616 size = size_for(map);
617 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
618 }
619 } else if (is_last_duplicate(map)) {
620 /* if this entry is identical to the previous one, just point it there */
621 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
622 } else {
623 /* not empty, not an identical copy of the previous entry */
624 size = size_for(map);
625 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
626 _last_offset = _offset;
627 _last = map;
628 }
629
630 assert(_mapping[i]._map == map, "check");
631 _offset += size;
632 }
633
634 int total = base + pairs + _offset;
635 DEBUG_ONLY(total += 8);
636 _required = total;
637 return total;
638 }
639
640 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
641 assert(offset < set->nr_of_bytes(), "check");
642 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
643 }
644
645 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
646 fill_pair(pair, map, offset, set);
647 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
648
649 new (addr) ImmutableOopMap(map);
650 return size_for(map);
651 }
652
653 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
654 ImmutableOopMapPair* pairs = set->get_pairs();
655
656 for (int i = 0; i < set->count(); ++i) {
657 const OopMap* map = _mapping[i]._map;
658 ImmutableOopMapPair* pair = NULL;
659 int size = 0;
660
661 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
662 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
663 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
664 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
665 }
666
667 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
668 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
669 }
670 }
671
672 #ifdef ASSERT
673 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
674 for (int i = 0; i < 8; ++i) {
675 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
676 }
677
678 for (int i = 0; i < set->count(); ++i) {
679 const ImmutableOopMapPair* pair = set->pair_at(i);
680 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
681 const ImmutableOopMap* map = pair->get_from(set);
682 int nr_of_bytes = map->nr_of_bytes();
683 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
684 }
685 }
686 #endif
687
688 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
689 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
690
691 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
692 fill(_new_set, _required);
693
694 DEBUG_ONLY(verify(buffer, _required, _new_set));
695
696 return _new_set;
697 }
698
699 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
700 _required = heap_size();
701
702 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
703 address buffer = NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
704 return generate_into(buffer);
705 }
706
707 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
708 ResourceMark mark;
709 ImmutableOopMapBuilder builder(oopmap_set);
710 return builder.build();
711 }
712
713
714 //------------------------------DerivedPointerTable---------------------------
715
716 #if COMPILER2_OR_JVMCI
717
718 class DerivedPointerTable::Entry : public CHeapObj<mtCompiler> {
719 oop* _location; // Location of derived pointer, also pointing to base
720 intptr_t _offset; // Offset from base pointer
721 Entry* volatile _next;
722
723 static Entry* volatile* next_ptr(Entry& entry) { return &entry._next; }
724
725 public:
726 Entry(oop* location, intptr_t offset) :
727 _location(location), _offset(offset), _next(NULL) {}
728
729 oop* location() const { return _location; }
730 intptr_t offset() const { return _offset; }
731 Entry* next() const { return _next; }
732
733 typedef LockFreeStack<Entry, &next_ptr> List;
734 static List* _list;
735 };
736
737 DerivedPointerTable::Entry::List* DerivedPointerTable::Entry::_list = NULL;
738 bool DerivedPointerTable::_active = false;
739
740 bool DerivedPointerTable::is_empty() {
741 return Entry::_list == NULL || Entry::_list->empty();
742 }
743
744 void DerivedPointerTable::clear() {
745 // The first time, we create the list. Otherwise it should be
746 // empty. If not, then we have probably forgotton to call
747 // update_pointers after last GC/Scavenge.
748 assert (!_active, "should not be active");
749 assert(is_empty(), "table not empty");
750 if (Entry::_list == NULL) {
751 void* mem = NEW_C_HEAP_OBJ(Entry::List, mtCompiler);
752 Entry::_list = ::new (mem) Entry::List();
753 }
754 _active = true;
755 }
756
757 // Returns value of location as an int
758 inline intptr_t value_of_loc(oop *pointer) {
759 return cast_from_oop<intptr_t>((*pointer));
760 }
761
762 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
763 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
764 assert(derived_loc != base_loc, "Base and derived in same location");
765 if (_active) {
766 assert(*derived_loc != (void*)base_loc, "location already added");
767 assert(Entry::_list != NULL, "list must exist");
768 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
769 // This assert is invalid because derived pointers can be
770 // arbitrarily far away from their base.
771 // assert(offset >= -1000000, "wrong derived pointer info");
772
773 if (TraceDerivedPointers) {
774 tty->print_cr(
775 "Add derived pointer@" INTPTR_FORMAT
776 " - Derived: " INTPTR_FORMAT
777 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
778 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
779 );
780 }
781 // Set derived oop location to point to base.
782 *derived_loc = (oop)base_loc;
783 Entry* entry = new Entry(derived_loc, offset);
784 Entry::_list->push(*entry);
785 }
786 }
787
788 void DerivedPointerTable::update_pointers() {
789 assert(Entry::_list != NULL, "list must exist");
790 Entry* entries = Entry::_list->pop_all();
791 while (entries != NULL) {
792 Entry* entry = entries;
793 entries = entry->next();
794 oop* derived_loc = entry->location();
795 intptr_t offset = entry->offset();
796 // The derived oop was setup to point to location of base
797 oop base = **(oop**)derived_loc;
798 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
799
800 *derived_loc = (oop)(((address)base) + offset);
801 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
802
803 if (TraceDerivedPointers) {
804 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
805 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
806 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
807 }
808
809 // Delete entry
810 delete entry;
811 }
812 assert(Entry::_list->empty(), "invariant");
813 _active = false;
814 }
815
816 #endif // COMPILER2_OR_JVMCI