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 "runtime/frame.inline.hpp"
36 #include "runtime/handles.inline.hpp"
37 #include "runtime/signature.hpp"
38 #include "utilities/align.hpp"
39 #ifdef COMPILER1
40 #include "c1/c1_Defs.hpp"
41 #endif
42 #ifdef COMPILER2
43 #include "opto/optoreg.hpp"
44 #endif
45
46 // OopMapStream
47
48 OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) {
49 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
50 _mask = oop_types_mask;
51 _size = oop_map->omv_count();
52 _position = 0;
53 _valid_omv = false;
54 }
55
56 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map, int oop_types_mask) {
57 _stream = new CompressedReadStream(oop_map->data_addr());
58 _mask = oop_types_mask;
59 _size = oop_map->count();
60 _position = 0;
61 _valid_omv = false;
62 }
63
64 void OopMapStream::find_next() {
65 while(_position++ < _size) {
66 _omv.read_from(_stream);
67 if(((int)_omv.type() & _mask) > 0) {
68 _valid_omv = true;
69 return;
70 }
71 }
72 _valid_omv = false;
73 }
74
75
76 // OopMap
77
78 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
79 // slots to hold 4-byte values like ints and floats in the LP64 build.
80 OopMap::OopMap(int frame_size, int arg_count) {
81 // OopMaps are usually quite so small, so pick a small initial size
82 set_write_stream(new CompressedWriteStream(32));
83 set_omv_count(0);
84
85 #ifdef ASSERT
86 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
87 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
88 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
89 #endif
90 }
91
92
93 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
94 // This constructor does a deep copy
95 // of the source OopMap.
96 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
97 set_omv_count(0);
98 set_offset(source->offset());
99
100 #ifdef ASSERT
101 _locs_length = source->_locs_length;
102 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
103 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
104 #endif
105
106 // We need to copy the entries too.
107 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
108 OopMapValue omv = oms.current();
109 omv.write_on(write_stream());
110 increment_count();
111 }
112 }
113
114
115 OopMap* OopMap::deep_copy() {
116 return new OopMap(_deep_copy_token, this);
117 }
118
119 void OopMap::copy_data_to(address addr) const {
120 memcpy(addr, write_stream()->buffer(), write_stream()->position());
121 }
122
123 int OopMap::heap_size() const {
124 int size = sizeof(OopMap);
125 int align = sizeof(void *) - 1;
126 size += write_stream()->position();
127 // Align to a reasonable ending point
128 size = ((size+align) & ~align);
129 return size;
130 }
131
132 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
133 // slots to hold 4-byte values like ints and floats in the LP64 build.
134 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
135
136 assert(reg->value() < _locs_length, "too big reg value for stack size");
137 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
138 debug_only( _locs_used[reg->value()] = x; )
139
140 OopMapValue o(reg, x);
141
142 if(x == OopMapValue::callee_saved_value) {
143 // This can never be a stack location, so we don't need to transform it.
144 assert(optional->is_reg(), "Trying to callee save a stack location");
145 o.set_content_reg(optional);
146 } else if(x == OopMapValue::derived_oop_value) {
147 o.set_content_reg(optional);
148 }
149
150 o.write_on(write_stream());
151 increment_count();
152 }
153
154
155 void OopMap::set_oop(VMReg reg) {
156 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
157 }
158
159
160 void OopMap::set_value(VMReg reg) {
161 // At this time, we don't need value entries in our OopMap.
162 }
163
164
165 void OopMap::set_narrowoop(VMReg reg) {
166 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
167 }
168
169
170 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
171 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
172 }
173
174
175 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
176 if( reg == derived_from_local_register ) {
177 // Actually an oop, derived shares storage with base,
178 set_oop(reg);
179 } else {
180 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
181 }
182 }
183
184 // OopMapSet
185
186 OopMapSet::OopMapSet() {
187 set_om_size(MinOopMapAllocation);
188 set_om_count(0);
189 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
190 set_om_data(temp);
191 }
192
193
194 void OopMapSet::grow_om_data() {
195 int new_size = om_size() * 2;
196 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
197 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
198 set_om_size(new_size);
199 set_om_data(new_data);
200 }
201
202 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
203 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
204
205 if(om_count() >= om_size()) {
206 grow_om_data();
207 }
208 map->set_offset(pc_offset);
209
210 #ifdef ASSERT
211 if(om_count() > 0) {
212 OopMap* last = at(om_count()-1);
213 if (last->offset() == map->offset() ) {
214 fatal("OopMap inserted twice");
215 }
216 if(last->offset() > map->offset()) {
217 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
218 om_count(),last->offset(),om_count()+1,map->offset());
219 }
220 }
221 #endif // ASSERT
222
223 set(om_count(),map);
224 increment_count();
225 }
226
227
228 int OopMapSet::heap_size() const {
229 // The space we use
230 int size = sizeof(OopMap);
231 int align = sizeof(void *) - 1;
232 size = ((size+align) & ~align);
233 size += om_count() * sizeof(OopMap*);
234
235 // Now add in the space needed for the indivdiual OopMaps
236 for(int i=0; i < om_count(); i++) {
237 size += at(i)->heap_size();
238 }
239 // We don't need to align this, it will be naturally pointer aligned
240 return size;
241 }
242
243
244 OopMap* OopMapSet::singular_oop_map() {
245 guarantee(om_count() == 1, "Make sure we only have a single gc point");
246 return at(0);
247 }
248
249
250 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
251 int i, len = om_count();
252 assert( len > 0, "must have pointer maps" );
253
254 // Scan through oopmaps. Stop when current offset is either equal or greater
255 // than the one we are looking for.
256 for( i = 0; i < len; i++) {
257 if( at(i)->offset() >= pc_offset )
258 break;
259 }
260
261 assert( i < len, "oopmap not found" );
262
263 OopMap* m = at(i);
264 assert( m->offset() == pc_offset, "oopmap not found" );
265 return m;
266 }
267
268 static void add_derived_oop(oop* base, oop* derived) {
269 #if !defined(TIERED) && !INCLUDE_JVMCI
270 COMPILER1_PRESENT(ShouldNotReachHere();)
271 #endif // !defined(TIERED) && !INCLUDE_JVMCI
272 #if COMPILER2_OR_JVMCI
273 DerivedPointerTable::add(derived, base);
274 #endif // COMPILER2_OR_JVMCI
275 }
276
277
278 #ifndef PRODUCT
279 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
280 // Print oopmap and regmap
281 tty->print_cr("------ ");
282 CodeBlob* cb = fr->cb();
283 const ImmutableOopMapSet* maps = cb->oop_maps();
284 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
285 map->print();
286 if( cb->is_nmethod() ) {
287 nmethod* nm = (nmethod*)cb;
288 // native wrappers have no scope data, it is implied
289 if (nm->is_native_method()) {
290 tty->print("bci: 0 (native)");
291 } else {
292 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
293 tty->print("bci: %d ",scope->bci());
294 }
295 }
296 tty->cr();
297 fr->print_on(tty);
298 tty->print(" ");
299 cb->print_value_on(tty); tty->cr();
300 reg_map->print();
301 tty->print_cr("------ ");
302
303 }
304 #endif // PRODUCT
305
306 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
307 // add derived oops to a table
308 all_do(fr, reg_map, f, add_derived_oop, &do_nothing_cl);
309 }
310
311
312 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
313 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
314 OopClosure* value_fn) {
315 CodeBlob* cb = fr->cb();
316 assert(cb != NULL, "no codeblob");
317
318 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
319
320 const ImmutableOopMapSet* maps = cb->oop_maps();
321 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
322 assert(map != NULL, "no ptr map found");
323
324 // handle derived pointers first (otherwise base pointer may be
325 // changed before derived pointer offset has been collected)
326 OopMapValue omv;
327 {
328 OopMapStream oms(map,OopMapValue::derived_oop_value);
329 if (!oms.is_done()) {
330 #ifndef TIERED
331 COMPILER1_PRESENT(ShouldNotReachHere();)
332 #if INCLUDE_JVMCI
333 if (UseJVMCICompiler) {
334 ShouldNotReachHere();
335 }
336 #endif
337 #endif // !TIERED
338 // Protect the operation on the derived pointers. This
339 // protects the addition of derived pointers to the shared
340 // derived pointer table in DerivedPointerTable::add().
341 MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
342 do {
343 omv = oms.current();
344 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
345 guarantee(loc != NULL, "missing saved register");
346 oop *derived_loc = loc;
347 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
348 // Ignore NULL oops and decoded NULL narrow oops which
349 // equal to Universe::narrow_oop_base when a narrow oop
350 // implicit null check is used in compiled code.
351 // The narrow_oop_base could be NULL or be the address
352 // of the page below heap depending on compressed oops mode.
353 if (base_loc != NULL && *base_loc != NULL && !Universe::is_narrow_oop_base(*base_loc)) {
354 derived_oop_fn(base_loc, derived_loc);
355 }
356 oms.next();
357 } while (!oms.is_done());
358 }
359 }
360
361 // We want coop and oop oop_types
362 int mask = OopMapValue::oop_value | OopMapValue::narrowoop_value;
363 {
364 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
365 omv = oms.current();
366 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
367 // It should be an error if no location can be found for a
368 // register mentioned as contained an oop of some kind. Maybe
369 // this was allowed previously because value_value items might
370 // be missing?
371 guarantee(loc != NULL, "missing saved register");
372 if ( omv.type() == OopMapValue::oop_value ) {
373 oop val = *loc;
374 if (val == NULL || Universe::is_narrow_oop_base(val)) {
375 // Ignore NULL oops and decoded NULL narrow oops which
376 // equal to Universe::narrow_oop_base when a narrow oop
377 // implicit null check is used in compiled code.
378 // The narrow_oop_base could be NULL or be the address
379 // of the page below heap depending on compressed oops mode.
380 continue;
381 }
382 #ifdef ASSERT
383 // We can not verify the oop here if we are using ZGC, the oop
384 // will be bad in case we had a safepoint between a load and a
385 // load barrier.
386 if (!UseZGC &&
387 ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) ||
388 !Universe::heap()->is_in_or_null(*loc))) {
389 tty->print_cr("# Found non oop pointer. Dumping state at failure");
390 // try to dump out some helpful debugging information
391 trace_codeblob_maps(fr, reg_map);
392 omv.print();
393 tty->print_cr("register r");
394 omv.reg()->print();
395 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
396 // do the real assert.
397 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
398 }
399 #endif // ASSERT
400 oop_fn->do_oop(loc);
401 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
402 narrowOop *nl = (narrowOop*)loc;
403 #ifndef VM_LITTLE_ENDIAN
404 VMReg vmReg = omv.reg();
405 // Don't do this on SPARC float registers as they can be individually addressed
406 if (!vmReg->is_stack() SPARC_ONLY(&& !vmReg->is_FloatRegister())) {
407 // compressed oops in registers only take up 4 bytes of an
408 // 8 byte register but they are in the wrong part of the
409 // word so adjust loc to point at the right place.
410 nl = (narrowOop*)((address)nl + 4);
411 }
412 #endif
413 oop_fn->do_oop(nl);
414 }
415 }
416 }
417 }
418
419
420 // Update callee-saved register info for the following frame
421 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
422 ResourceMark rm;
423 CodeBlob* cb = fr->cb();
424 assert(cb != NULL, "no codeblob");
425
426 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
427 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
428 "already updated this map; do not 'update' it twice!" );
429 debug_only(reg_map->_update_for_id = fr->id());
430
431 // Check if caller must update oop argument
432 assert((reg_map->include_argument_oops() ||
433 !cb->caller_must_gc_arguments(reg_map->thread())),
434 "include_argument_oops should already be set");
435
436 // Scan through oopmap and find location of all callee-saved registers
437 // (we do not do update in place, since info could be overwritten)
438
439 address pc = fr->pc();
440 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
441 assert(map != NULL, "no ptr map found");
442 DEBUG_ONLY(int nof_callee = 0;)
443
444 for (OopMapStream oms(map, OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
445 OopMapValue omv = oms.current();
446 VMReg reg = omv.content_reg();
447 oop* loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
448 reg_map->set_location(reg, (address) loc);
449 DEBUG_ONLY(nof_callee++;)
450 }
451
452 // Check that runtime stubs save all callee-saved registers
453 #ifdef COMPILER2
454 assert(cb->is_compiled_by_c1() || cb->is_compiled_by_jvmci() || !cb->is_runtime_stub() ||
455 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
456 "must save all");
457 #endif // COMPILER2
458 }
459
460 //=============================================================================
461 // Non-Product code
462
463 #ifndef PRODUCT
464
465 bool ImmutableOopMap::has_derived_pointer() const {
466 #if !defined(TIERED) && !INCLUDE_JVMCI
467 COMPILER1_PRESENT(return false);
468 #endif // !TIERED
469 #if COMPILER2_OR_JVMCI
470 OopMapStream oms(this,OopMapValue::derived_oop_value);
471 return oms.is_done();
472 #else
473 return false;
474 #endif // COMPILER2_OR_JVMCI
475 }
476
477 #endif //PRODUCT
478
479 // Printing code is present in product build for -XX:+PrintAssembly.
480
481 static
482 void print_register_type(OopMapValue::oop_types x, VMReg optional,
483 outputStream* st) {
484 switch( x ) {
485 case OopMapValue::oop_value:
486 st->print("Oop");
487 break;
488 case OopMapValue::narrowoop_value:
489 st->print("NarrowOop");
490 break;
491 case OopMapValue::callee_saved_value:
492 st->print("Callers_");
493 optional->print_on(st);
494 break;
495 case OopMapValue::derived_oop_value:
496 st->print("Derived_oop_");
497 optional->print_on(st);
498 break;
499 default:
500 ShouldNotReachHere();
501 }
502 }
503
504 void OopMapValue::print_on(outputStream* st) const {
505 reg()->print_on(st);
506 st->print("=");
507 print_register_type(type(),content_reg(),st);
508 st->print(" ");
509 }
510
511 void ImmutableOopMap::print_on(outputStream* st) const {
512 OopMapValue omv;
513 st->print("ImmutableOopMap {");
514 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
515 omv = oms.current();
516 omv.print_on(st);
517 }
518 st->print("}");
519 }
520
521 void OopMap::print_on(outputStream* st) const {
522 OopMapValue omv;
523 st->print("OopMap {");
524 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
525 omv = oms.current();
526 omv.print_on(st);
527 }
528 // Print hex offset in addition.
529 st->print("off=%d/0x%x}", (int) offset(), (int) offset());
530 }
531
532 void ImmutableOopMapSet::print_on(outputStream* st) const {
533 const ImmutableOopMap* last = NULL;
534 const int len = count();
535
536 st->print_cr("ImmutableOopMapSet contains %d OopMaps", len);
537
538 for (int i = 0; i < len; i++) {
539 const ImmutableOopMapPair* pair = pair_at(i);
540 const ImmutableOopMap* map = pair->get_from(this);
541 if (map != last) {
542 st->cr();
543 map->print_on(st);
544 st->print(" pc offsets: ");
545 }
546 last = map;
547 st->print("%d ", pair->pc_offset());
548 }
549 st->cr();
550 }
551
552 void OopMapSet::print_on(outputStream* st) const {
553 const int len = om_count();
554
555 st->print_cr("OopMapSet contains %d OopMaps", len);
556
557 for(int i = 0; i < len; i++) {
558 OopMap* m = at(i);
559 st->print_cr("#%d ",i);
560 m->print_on(st);
561 st->cr();
562 }
563 st->cr();
564 }
565
566 bool OopMap::equals(const OopMap* other) const {
567 if (other->_omv_count != _omv_count) {
568 return false;
569 }
570 if (other->write_stream()->position() != write_stream()->position()) {
571 return false;
572 }
573 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
574 return false;
575 }
576 return true;
577 }
578
579 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
580 ImmutableOopMapPair* pairs = get_pairs();
581 ImmutableOopMapPair* last = NULL;
582
583 for (int i = 0; i < _count; ++i) {
584 if (pairs[i].pc_offset() >= pc_offset) {
585 last = &pairs[i];
586 break;
587 }
588 }
589
590 // Heal Coverity issue: potential index out of bounds access.
591 guarantee(last != NULL, "last may not be null");
592 assert(last->pc_offset() == pc_offset, "oopmap not found");
593 return last->get_from(this);
594 }
595
596 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
597 return set->oopmap_at_offset(_oopmap_offset);
598 }
599
600 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
601 address addr = data_addr();
602 oopmap->copy_data_to(addr);
603 }
604
605 #ifdef ASSERT
606 int ImmutableOopMap::nr_of_bytes() const {
607 OopMapStream oms(this);
608
609 while (!oms.is_done()) {
610 oms.next();
611 }
612 return sizeof(ImmutableOopMap) + oms.stream_position();
613 }
614 #endif
615
616 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(NULL) {
617 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
618 }
619
620 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
621 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
622 }
623
624 int ImmutableOopMapBuilder::heap_size() {
625 int base = sizeof(ImmutableOopMapSet);
626 base = align_up(base, 8);
627
628 // all of ours pc / offset pairs
629 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
630 pairs = align_up(pairs, 8);
631
632 for (int i = 0; i < _set->size(); ++i) {
633 int size = 0;
634 OopMap* map = _set->at(i);
635
636 if (is_empty(map)) {
637 /* only keep a single empty map in the set */
638 if (has_empty()) {
639 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
640 } else {
641 _empty_offset = _offset;
642 _empty = map;
643 size = size_for(map);
644 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
645 }
646 } else if (is_last_duplicate(map)) {
647 /* if this entry is identical to the previous one, just point it there */
648 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
649 } else {
650 /* not empty, not an identical copy of the previous entry */
651 size = size_for(map);
652 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
653 _last_offset = _offset;
654 _last = map;
655 }
656
657 assert(_mapping[i]._map == map, "check");
658 _offset += size;
659 }
660
661 int total = base + pairs + _offset;
662 DEBUG_ONLY(total += 8);
663 _required = total;
664 return total;
665 }
666
667 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
668 assert(offset < set->nr_of_bytes(), "check");
669 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
670 }
671
672 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
673 fill_pair(pair, map, offset, set);
674 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
675
676 new (addr) ImmutableOopMap(map);
677 return size_for(map);
678 }
679
680 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
681 ImmutableOopMapPair* pairs = set->get_pairs();
682
683 for (int i = 0; i < set->count(); ++i) {
684 const OopMap* map = _mapping[i]._map;
685 ImmutableOopMapPair* pair = NULL;
686 int size = 0;
687
688 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
689 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
690 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
691 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
692 }
693
694 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
695 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
696 }
697 }
698
699 #ifdef ASSERT
700 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
701 for (int i = 0; i < 8; ++i) {
702 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
703 }
704
705 for (int i = 0; i < set->count(); ++i) {
706 const ImmutableOopMapPair* pair = set->pair_at(i);
707 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
708 const ImmutableOopMap* map = pair->get_from(set);
709 int nr_of_bytes = map->nr_of_bytes();
710 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
711 }
712 }
713 #endif
714
715 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
716 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
717
718 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
719 fill(_new_set, _required);
720
721 DEBUG_ONLY(verify(buffer, _required, _new_set));
722
723 return _new_set;
724 }
725
726 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
727 _required = heap_size();
728
729 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
730 address buffer = (address) NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
731 return generate_into(buffer);
732 }
733
734 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
735 ResourceMark mark;
736 ImmutableOopMapBuilder builder(oopmap_set);
737 return builder.build();
738 }
739
740
741 //------------------------------DerivedPointerTable---------------------------
742
743 #if COMPILER2_OR_JVMCI
744
745 class DerivedPointerEntry : public CHeapObj<mtCompiler> {
746 private:
747 oop* _location; // Location of derived pointer (also pointing to the base)
748 intptr_t _offset; // Offset from base pointer
749 public:
750 DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
751 oop* location() { return _location; }
752 intptr_t offset() { return _offset; }
753 };
754
755
756 GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
757 bool DerivedPointerTable::_active = false;
758
759
760 void DerivedPointerTable::clear() {
761 // The first time, we create the list. Otherwise it should be
762 // empty. If not, then we have probably forgotton to call
763 // update_pointers after last GC/Scavenge.
764 assert (!_active, "should not be active");
765 assert(_list == NULL || _list->length() == 0, "table not empty");
766 if (_list == NULL) {
767 _list = new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
768 }
769 _active = true;
770 }
771
772
773 // Returns value of location as an int
774 intptr_t value_of_loc(oop *pointer) { return cast_from_oop<intptr_t>((*pointer)); }
775
776
777 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
778 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
779 assert(derived_loc != base_loc, "Base and derived in same location");
780 if (_active) {
781 assert(*derived_loc != (void*)base_loc, "location already added");
782 assert(_list != NULL, "list must exist");
783 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
784 // This assert is invalid because derived pointers can be
785 // arbitrarily far away from their base.
786 // assert(offset >= -1000000, "wrong derived pointer info");
787
788 if (TraceDerivedPointers) {
789 tty->print_cr(
790 "Add derived pointer@" INTPTR_FORMAT
791 " - Derived: " INTPTR_FORMAT
792 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
793 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
794 );
795 }
796 // Set derived oop location to point to base.
797 *derived_loc = (oop)base_loc;
798 assert_lock_strong(DerivedPointerTableGC_lock);
799 DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
800 _list->append(entry);
801 }
802 }
803
804
805 void DerivedPointerTable::update_pointers() {
806 assert(_list != NULL, "list must exist");
807 for(int i = 0; i < _list->length(); i++) {
808 DerivedPointerEntry* entry = _list->at(i);
809 oop* derived_loc = entry->location();
810 intptr_t offset = entry->offset();
811 // The derived oop was setup to point to location of base
812 oop base = **(oop**)derived_loc;
813 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
814
815 *derived_loc = (oop)(((address)base) + offset);
816 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
817
818 if (TraceDerivedPointers) {
819 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
820 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
821 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
822 }
823
824 // Delete entry
825 delete entry;
826 _list->at_put(i, NULL);
827 }
828 // Clear list, so it is ready for next traversal (this is an invariant)
829 if (TraceDerivedPointers && !_list->is_empty()) {
830 tty->print_cr("--------------------------");
831 }
832 _list->clear();
833 _active = false;
834 }
835
836 #endif // COMPILER2_OR_JVMCI