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, int oop_types_mask) {
52 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
53 _mask = oop_types_mask;
54 _size = oop_map->omv_count();
55 _position = 0;
56 _valid_omv = false;
57 }
58
59 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map, int oop_types_mask) {
60 _stream = new CompressedReadStream(oop_map->data_addr());
61 _mask = oop_types_mask;
62 _size = oop_map->count();
63 _position = 0;
64 _valid_omv = false;
65 }
66
67 void OopMapStream::find_next() {
68 while(_position++ < _size) {
69 _omv.read_from(_stream);
70 if(((int)_omv.type() & _mask) > 0) {
71 _valid_omv = true;
72 return;
73 }
74 }
75 _valid_omv = false;
76 }
77
78
79 // OopMap
80
81 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
82 // slots to hold 4-byte values like ints and floats in the LP64 build.
83 OopMap::OopMap(int frame_size, int arg_count) {
84 // OopMaps are usually quite so small, so pick a small initial size
85 set_write_stream(new CompressedWriteStream(32));
86 set_omv_count(0);
87
88 #ifdef ASSERT
89 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
90 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
91 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
92 #endif
93 }
94
95
96 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
97 // This constructor does a deep copy
98 // of the source OopMap.
99 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
100 set_omv_count(0);
101 set_offset(source->offset());
102
103 #ifdef ASSERT
104 _locs_length = source->_locs_length;
105 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
106 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
107 #endif
108
109 // We need to copy the entries too.
110 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
111 OopMapValue omv = oms.current();
112 omv.write_on(write_stream());
113 increment_count();
114 }
115 }
116
117
118 OopMap* OopMap::deep_copy() {
119 return new OopMap(_deep_copy_token, this);
120 }
121
122 void OopMap::copy_data_to(address addr) const {
123 memcpy(addr, write_stream()->buffer(), write_stream()->position());
124 }
125
126 int OopMap::heap_size() const {
127 int size = sizeof(OopMap);
128 int align = sizeof(void *) - 1;
129 size += write_stream()->position();
130 // Align to a reasonable ending point
131 size = ((size+align) & ~align);
132 return size;
133 }
134
135 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
136 // slots to hold 4-byte values like ints and floats in the LP64 build.
137 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
138
139 assert(reg->value() < _locs_length, "too big reg value for stack size");
140 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
141 debug_only( _locs_used[reg->value()] = x; )
142
143 OopMapValue o(reg, x);
144
145 if(x == OopMapValue::callee_saved_value) {
146 // This can never be a stack location, so we don't need to transform it.
147 assert(optional->is_reg(), "Trying to callee save a stack location");
148 o.set_content_reg(optional);
149 } else if(x == OopMapValue::derived_oop_value) {
150 o.set_content_reg(optional);
151 }
152
153 o.write_on(write_stream());
154 increment_count();
155 }
156
157
158 void OopMap::set_oop(VMReg reg) {
159 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
160 }
161
162
163 void OopMap::set_value(VMReg reg) {
164 // At this time, we don't need value entries in our OopMap.
165 }
166
167
168 void OopMap::set_narrowoop(VMReg reg) {
169 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
170 }
171
172
173 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
174 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
175 }
176
177
178 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
179 if( reg == derived_from_local_register ) {
180 // Actually an oop, derived shares storage with base,
181 set_oop(reg);
182 } else {
183 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
184 }
185 }
186
187 // OopMapSet
188
189 OopMapSet::OopMapSet() {
190 set_om_size(MinOopMapAllocation);
191 set_om_count(0);
192 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
193 set_om_data(temp);
194 }
195
196
197 void OopMapSet::grow_om_data() {
198 int new_size = om_size() * 2;
199 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
200 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
201 set_om_size(new_size);
202 set_om_data(new_data);
203 }
204
205 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
206 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
207
208 if(om_count() >= om_size()) {
209 grow_om_data();
210 }
211 map->set_offset(pc_offset);
212
213 #ifdef ASSERT
214 if(om_count() > 0) {
215 OopMap* last = at(om_count()-1);
216 if (last->offset() == map->offset() ) {
217 fatal("OopMap inserted twice");
218 }
219 if(last->offset() > map->offset()) {
220 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
221 om_count(),last->offset(),om_count()+1,map->offset());
222 }
223 }
224 #endif // ASSERT
225
226 set(om_count(),map);
227 increment_count();
228 }
229
230
231 int OopMapSet::heap_size() const {
232 // The space we use
233 int size = sizeof(OopMap);
234 int align = sizeof(void *) - 1;
235 size = ((size+align) & ~align);
236 size += om_count() * sizeof(OopMap*);
237
238 // Now add in the space needed for the indivdiual OopMaps
239 for(int i=0; i < om_count(); i++) {
240 size += at(i)->heap_size();
241 }
242 // We don't need to align this, it will be naturally pointer aligned
243 return size;
244 }
245
246
247 OopMap* OopMapSet::singular_oop_map() {
248 guarantee(om_count() == 1, "Make sure we only have a single gc point");
249 return at(0);
250 }
251
252
253 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
254 int i, len = om_count();
255 assert( len > 0, "must have pointer maps" );
256
257 // Scan through oopmaps. Stop when current offset is either equal or greater
258 // than the one we are looking for.
259 for( i = 0; i < len; i++) {
260 if( at(i)->offset() >= pc_offset )
261 break;
262 }
263
264 assert( i < len, "oopmap not found" );
265
266 OopMap* m = at(i);
267 assert( m->offset() == pc_offset, "oopmap not found" );
268 return m;
269 }
270
271 static void add_derived_oop(oop* base, oop* derived) {
272 #if !defined(TIERED) && !INCLUDE_JVMCI
273 COMPILER1_PRESENT(ShouldNotReachHere();)
274 #endif // !defined(TIERED) && !INCLUDE_JVMCI
275 #if COMPILER2_OR_JVMCI
276 DerivedPointerTable::add(derived, base);
277 #endif // COMPILER2_OR_JVMCI
278 }
279
280
281 #ifndef PRODUCT
282 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
283 // Print oopmap and regmap
284 tty->print_cr("------ ");
285 CodeBlob* cb = fr->cb();
286 const ImmutableOopMapSet* maps = cb->oop_maps();
287 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
288 map->print();
289 if( cb->is_nmethod() ) {
290 nmethod* nm = (nmethod*)cb;
291 // native wrappers have no scope data, it is implied
292 if (nm->is_native_method()) {
293 tty->print("bci: 0 (native)");
294 } else {
295 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
296 tty->print("bci: %d ",scope->bci());
297 }
298 }
299 tty->cr();
300 fr->print_on(tty);
301 tty->print(" ");
302 cb->print_value_on(tty); tty->cr();
303 reg_map->print();
304 tty->print_cr("------ ");
305
306 }
307 #endif // PRODUCT
308
309 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
310 // add derived oops to a table
311 all_do(fr, reg_map, f, add_derived_oop, &do_nothing_cl);
312 }
313
314
315 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
316 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
317 OopClosure* value_fn) {
318 CodeBlob* cb = fr->cb();
319 assert(cb != NULL, "no codeblob");
320
321 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
322
323 const ImmutableOopMapSet* maps = cb->oop_maps();
324 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
325 assert(map != NULL, "no ptr map found");
326
327 // handle derived pointers first (otherwise base pointer may be
328 // changed before derived pointer offset has been collected)
329 OopMapValue omv;
330 {
331 OopMapStream oms(map,OopMapValue::derived_oop_value);
332 if (!oms.is_done()) {
333 #ifndef TIERED
334 COMPILER1_PRESENT(ShouldNotReachHere();)
335 #if INCLUDE_JVMCI
336 if (UseJVMCICompiler) {
337 ShouldNotReachHere();
338 }
339 #endif
340 #endif // !TIERED
341 do {
342 omv = oms.current();
343 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
344 guarantee(loc != NULL, "missing saved register");
345 oop *derived_loc = loc;
346 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
347 // Ignore NULL oops and decoded NULL narrow oops which
348 // equal to CompressedOops::base() when a narrow oop
349 // implicit null check is used in compiled code.
350 // The narrow_oop_base could be NULL or be the address
351 // of the page below heap depending on compressed oops mode.
352 if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
353 derived_oop_fn(base_loc, derived_loc);
354 }
355 oms.next();
356 } while (!oms.is_done());
357 }
358 }
359
360 // We want coop and oop oop_types
361 int mask = OopMapValue::oop_value | OopMapValue::narrowoop_value;
362 {
363 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
364 omv = oms.current();
365 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
366 // It should be an error if no location can be found for a
367 // register mentioned as contained an oop of some kind. Maybe
368 // this was allowed previously because value_value items might
369 // be missing?
370 guarantee(loc != NULL, "missing saved register");
371 if ( omv.type() == OopMapValue::oop_value ) {
372 oop val = *loc;
373 if (val == NULL || CompressedOops::is_base(val)) {
374 // Ignore NULL oops and decoded NULL narrow oops which
375 // equal to CompressedOops::base() when a narrow oop
376 // implicit null check is used in compiled code.
377 // The narrow_oop_base could be NULL or be the address
378 // of the page below heap depending on compressed oops mode.
379 continue;
380 }
381 #ifdef ASSERT
382 if ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) ||
383 !Universe::heap()->is_in_or_null(*loc)) {
384 tty->print_cr("# Found non oop pointer. Dumping state at failure");
385 // try to dump out some helpful debugging information
386 trace_codeblob_maps(fr, reg_map);
387 omv.print();
388 tty->print_cr("register r");
389 omv.reg()->print();
390 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
391 // do the real assert.
392 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
393 }
394 #endif // ASSERT
395 oop_fn->do_oop(loc);
396 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
397 narrowOop *nl = (narrowOop*)loc;
398 #ifndef VM_LITTLE_ENDIAN
399 VMReg vmReg = omv.reg();
400 // Don't do this on SPARC float registers as they can be individually addressed
401 if (!vmReg->is_stack() SPARC_ONLY(&& !vmReg->is_FloatRegister())) {
402 // compressed oops in registers only take up 4 bytes of an
403 // 8 byte register but they are in the wrong part of the
404 // word so adjust loc to point at the right place.
405 nl = (narrowOop*)((address)nl + 4);
406 }
407 #endif
408 oop_fn->do_oop(nl);
409 }
410 }
411 }
412 }
413
414
415 // Update callee-saved register info for the following frame
416 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
417 ResourceMark rm;
418 CodeBlob* cb = fr->cb();
419 assert(cb != NULL, "no codeblob");
420
421 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
422 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
423 "already updated this map; do not 'update' it twice!" );
424 debug_only(reg_map->_update_for_id = fr->id());
425
426 // Check if caller must update oop argument
427 assert((reg_map->include_argument_oops() ||
428 !cb->caller_must_gc_arguments(reg_map->thread())),
429 "include_argument_oops should already be set");
430
431 // Scan through oopmap and find location of all callee-saved registers
432 // (we do not do update in place, since info could be overwritten)
433
434 address pc = fr->pc();
435 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
436 assert(map != NULL, "no ptr map found");
437 DEBUG_ONLY(int nof_callee = 0;)
438
439 for (OopMapStream oms(map, OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
440 OopMapValue omv = oms.current();
441 VMReg reg = omv.content_reg();
442 oop* loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
443 reg_map->set_location(reg, (address) loc);
444 DEBUG_ONLY(nof_callee++;)
445 }
446
447 // Check that runtime stubs save all callee-saved registers
448 #ifdef COMPILER2
449 assert(cb->is_compiled_by_c1() || cb->is_compiled_by_jvmci() || !cb->is_runtime_stub() ||
450 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
451 "must save all");
452 #endif // COMPILER2
453 }
454
455 //=============================================================================
456 // Non-Product code
457
458 #ifndef PRODUCT
459
460 bool ImmutableOopMap::has_derived_pointer() const {
461 #if !defined(TIERED) && !INCLUDE_JVMCI
462 COMPILER1_PRESENT(return false);
463 #endif // !TIERED
464 #if COMPILER2_OR_JVMCI
465 OopMapStream oms(this,OopMapValue::derived_oop_value);
466 return oms.is_done();
467 #else
468 return false;
469 #endif // COMPILER2_OR_JVMCI
470 }
471
472 #endif //PRODUCT
473
474 // Printing code is present in product build for -XX:+PrintAssembly.
475
476 static
477 void print_register_type(OopMapValue::oop_types x, VMReg optional,
478 outputStream* st) {
479 switch( x ) {
480 case OopMapValue::oop_value:
481 st->print("Oop");
482 break;
483 case OopMapValue::narrowoop_value:
484 st->print("NarrowOop");
485 break;
486 case OopMapValue::callee_saved_value:
487 st->print("Callers_");
488 optional->print_on(st);
489 break;
490 case OopMapValue::derived_oop_value:
491 st->print("Derived_oop_");
492 optional->print_on(st);
493 break;
494 default:
495 ShouldNotReachHere();
496 }
497 }
498
499 void OopMapValue::print_on(outputStream* st) const {
500 reg()->print_on(st);
501 st->print("=");
502 print_register_type(type(),content_reg(),st);
503 st->print(" ");
504 }
505
506 void OopMapValue::print() const { print_on(tty); }
507
508 void ImmutableOopMap::print_on(outputStream* st) const {
509 OopMapValue omv;
510 st->print("ImmutableOopMap {");
511 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
512 omv = oms.current();
513 omv.print_on(st);
514 }
515 st->print("}");
516 }
517
518 void ImmutableOopMap::print() const { print_on(tty); }
519
520 void OopMap::print_on(outputStream* st) const {
521 OopMapValue omv;
522 st->print("OopMap {");
523 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
524 omv = oms.current();
525 omv.print_on(st);
526 }
527 // Print hex offset in addition.
528 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
529 }
530
531 void OopMap::print() const { print_on(tty); }
532
533 void ImmutableOopMapSet::print_on(outputStream* st) const {
534 const ImmutableOopMap* last = NULL;
535 const int len = count();
536
537 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
538
539 for (int i = 0; i < len; i++) {
540 const ImmutableOopMapPair* pair = pair_at(i);
541 const ImmutableOopMap* map = pair->get_from(this);
542 if (map != last) {
543 st->cr();
544 map->print_on(st);
545 st->print(" pc offsets: ");
546 }
547 last = map;
548 st->print("%d ", pair->pc_offset());
549 }
550 st->cr();
551 }
552
553 void ImmutableOopMapSet::print() const { print_on(tty); }
554
555 void OopMapSet::print_on(outputStream* st) const {
556 const int len = om_count();
557
558 st->print_cr("OopMapSet contains %d OopMaps", len);
559
560 for( int i = 0; i < len; i++) {
561 OopMap* m = at(i);
562 st->print_cr("#%d ",i);
563 m->print_on(st);
564 st->cr();
565 }
566 st->cr();
567 }
568
569 void OopMapSet::print() const { print_on(tty); }
570
571 bool OopMap::equals(const OopMap* other) const {
572 if (other->_omv_count != _omv_count) {
573 return false;
574 }
575 if (other->write_stream()->position() != write_stream()->position()) {
576 return false;
577 }
578 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
579 return false;
580 }
581 return true;
582 }
583
584 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
585 ImmutableOopMapPair* pairs = get_pairs();
586 ImmutableOopMapPair* last = NULL;
587
588 for (int i = 0; i < _count; ++i) {
589 if (pairs[i].pc_offset() >= pc_offset) {
590 last = &pairs[i];
591 break;
592 }
593 }
594
595 // Heal Coverity issue: potential index out of bounds access.
596 guarantee(last != NULL, "last may not be null");
597 assert(last->pc_offset() == pc_offset, "oopmap not found");
598 return last->get_from(this);
599 }
600
601 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
602 return set->oopmap_at_offset(_oopmap_offset);
603 }
604
605 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
606 address addr = data_addr();
607 oopmap->copy_data_to(addr);
608 }
609
610 #ifdef ASSERT
611 int ImmutableOopMap::nr_of_bytes() const {
612 OopMapStream oms(this);
613
614 while (!oms.is_done()) {
615 oms.next();
616 }
617 return sizeof(ImmutableOopMap) + oms.stream_position();
618 }
619 #endif
620
621 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(NULL) {
622 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
623 }
624
625 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
626 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
627 }
628
629 int ImmutableOopMapBuilder::heap_size() {
630 int base = sizeof(ImmutableOopMapSet);
631 base = align_up(base, 8);
632
633 // all of ours pc / offset pairs
634 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
635 pairs = align_up(pairs, 8);
636
637 for (int i = 0; i < _set->size(); ++i) {
638 int size = 0;
639 OopMap* map = _set->at(i);
640
641 if (is_empty(map)) {
642 /* only keep a single empty map in the set */
643 if (has_empty()) {
644 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
645 } else {
646 _empty_offset = _offset;
647 _empty = map;
648 size = size_for(map);
649 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
650 }
651 } else if (is_last_duplicate(map)) {
652 /* if this entry is identical to the previous one, just point it there */
653 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
654 } else {
655 /* not empty, not an identical copy of the previous entry */
656 size = size_for(map);
657 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
658 _last_offset = _offset;
659 _last = map;
660 }
661
662 assert(_mapping[i]._map == map, "check");
663 _offset += size;
664 }
665
666 int total = base + pairs + _offset;
667 DEBUG_ONLY(total += 8);
668 _required = total;
669 return total;
670 }
671
672 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
673 assert(offset < set->nr_of_bytes(), "check");
674 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
675 }
676
677 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
678 fill_pair(pair, map, offset, set);
679 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
680
681 new (addr) ImmutableOopMap(map);
682 return size_for(map);
683 }
684
685 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
686 ImmutableOopMapPair* pairs = set->get_pairs();
687
688 for (int i = 0; i < set->count(); ++i) {
689 const OopMap* map = _mapping[i]._map;
690 ImmutableOopMapPair* pair = NULL;
691 int size = 0;
692
693 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
694 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
695 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
696 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
697 }
698
699 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
700 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
701 }
702 }
703
704 #ifdef ASSERT
705 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
706 for (int i = 0; i < 8; ++i) {
707 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
708 }
709
710 for (int i = 0; i < set->count(); ++i) {
711 const ImmutableOopMapPair* pair = set->pair_at(i);
712 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
713 const ImmutableOopMap* map = pair->get_from(set);
714 int nr_of_bytes = map->nr_of_bytes();
715 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
716 }
717 }
718 #endif
719
720 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
721 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
722
723 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
724 fill(_new_set, _required);
725
726 DEBUG_ONLY(verify(buffer, _required, _new_set));
727
728 return _new_set;
729 }
730
731 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
732 _required = heap_size();
733
734 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
735 address buffer = (address) NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
736 return generate_into(buffer);
737 }
738
739 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
740 ResourceMark mark;
741 ImmutableOopMapBuilder builder(oopmap_set);
742 return builder.build();
743 }
744
745
746 //------------------------------DerivedPointerTable---------------------------
747
748 #if COMPILER2_OR_JVMCI
749
750 class DerivedPointerTable::Entry : public CHeapObj<mtCompiler> {
751 oop* _location; // Location of derived pointer, also pointing to base
752 intptr_t _offset; // Offset from base pointer
753 Entry* volatile _next;
754
755 static Entry* volatile* next_ptr(Entry& entry) { return &entry._next; }
756
757 public:
758 Entry(oop* location, intptr_t offset) :
759 _location(location), _offset(offset), _next(NULL) {}
760
761 oop* location() const { return _location; }
762 intptr_t offset() const { return _offset; }
763 Entry* next() const { return _next; }
764
765 typedef LockFreeStack<Entry, &next_ptr> List;
766 static List* _list;
767 };
768
769 DerivedPointerTable::Entry::List* DerivedPointerTable::Entry::_list = NULL;
770 bool DerivedPointerTable::_active = false;
771
772 bool DerivedPointerTable::is_empty() {
773 return Entry::_list == NULL || Entry::_list->empty();
774 }
775
776 void DerivedPointerTable::clear() {
777 // The first time, we create the list. Otherwise it should be
778 // empty. If not, then we have probably forgotton to call
779 // update_pointers after last GC/Scavenge.
780 assert (!_active, "should not be active");
781 assert(is_empty(), "table not empty");
782 if (Entry::_list == NULL) {
783 void* mem = NEW_C_HEAP_OBJ(Entry::List, mtCompiler);
784 Entry::_list = ::new (mem) Entry::List();
785 }
786 _active = true;
787 }
788
789 // Returns value of location as an int
790 inline intptr_t value_of_loc(oop *pointer) {
791 return cast_from_oop<intptr_t>((*pointer));
792 }
793
794 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
795 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
796 assert(derived_loc != base_loc, "Base and derived in same location");
797 if (_active) {
798 assert(*derived_loc != (void*)base_loc, "location already added");
799 assert(Entry::_list != NULL, "list must exist");
800 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
801 // This assert is invalid because derived pointers can be
802 // arbitrarily far away from their base.
803 // assert(offset >= -1000000, "wrong derived pointer info");
804
805 if (TraceDerivedPointers) {
806 tty->print_cr(
807 "Add derived pointer@" INTPTR_FORMAT
808 " - Derived: " INTPTR_FORMAT
809 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
810 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
811 );
812 }
813 // Set derived oop location to point to base.
814 *derived_loc = (oop)base_loc;
815 Entry* entry = new Entry(derived_loc, offset);
816 Entry::_list->push(*entry);
817 }
818 }
819
820 void DerivedPointerTable::update_pointers() {
821 assert(Entry::_list != NULL, "list must exist");
822 Entry* entries = Entry::_list->pop_all();
823 while (entries != NULL) {
824 Entry* entry = entries;
825 entries = entry->next();
826 oop* derived_loc = entry->location();
827 intptr_t offset = entry->offset();
828 // The derived oop was setup to point to location of base
829 oop base = **(oop**)derived_loc;
830 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
831
832 *derived_loc = (oop)(((address)base) + offset);
833 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
834
835 if (TraceDerivedPointers) {
836 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
837 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
838 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
839 }
840
841 // Delete entry
842 delete entry;
843 }
844 assert(Entry::_list->empty(), "invariant");
845 _active = false;
846 }
847
848 #endif // COMPILER2_OR_JVMCI