1 /*
2 * Copyright (c) 1998, 2015, 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/resourceArea.hpp"
34 #include "runtime/frame.inline.hpp"
35 #include "runtime/signature.hpp"
36 #ifdef COMPILER1
37 #include "c1/c1_Defs.hpp"
38 #endif
39 #ifdef COMPILER2
40 #include "opto/optoreg.hpp"
41 #endif
42
43 // OopMapStream
44
45 OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) {
46 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
47 _mask = oop_types_mask;
48 _size = oop_map->omv_count();
49 _position = 0;
50 _valid_omv = false;
51 }
52
53 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map, int oop_types_mask) {
54 _stream = new CompressedReadStream(oop_map->data_addr());
55 _mask = oop_types_mask;
56 _size = oop_map->count();
57 _position = 0;
58 _valid_omv = false;
59 }
60
61
62 void OopMapStream::find_next() {
63 while(_position++ < _size) {
64 _omv.read_from(_stream);
65 if(((int)_omv.type() & _mask) > 0) {
66 _valid_omv = true;
67 return;
68 }
69 }
70 _valid_omv = false;
71 }
72
73
74 // OopMap
75
76 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
77 // slots to hold 4-byte values like ints and floats in the LP64 build.
78 OopMap::OopMap(int frame_size, int arg_count) {
79 // OopMaps are usually quite so small, so pick a small initial size
80 set_write_stream(new CompressedWriteStream(32));
81 set_omv_count(0);
82
83 #ifdef ASSERT
84 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
85 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
86 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
87 #endif
88 }
89
90
91 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
92 // This constructor does a deep copy
93 // of the source OopMap.
94 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
95 set_omv_count(0);
96 set_offset(source->offset());
97
98 #ifdef ASSERT
99 _locs_length = source->_locs_length;
100 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
101 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
102 #endif
103
104 // We need to copy the entries too.
105 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
106 OopMapValue omv = oms.current();
107 omv.write_on(write_stream());
108 increment_count();
109 }
110 }
111
112
113 OopMap* OopMap::deep_copy() {
114 return new OopMap(_deep_copy_token, this);
115 }
116
117 void OopMap::copy_data_to(address addr) const {
118 memcpy(addr, write_stream()->buffer(), write_stream()->position());
119 }
120
121 int OopMap::heap_size() const {
122 int size = sizeof(OopMap);
123 int align = sizeof(void *) - 1;
124 size += write_stream()->position();
125 // Align to a reasonable ending point
126 size = ((size+align) & ~align);
127 return size;
128 }
129
130 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
131 // slots to hold 4-byte values like ints and floats in the LP64 build.
132 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
133
134 assert(reg->value() < _locs_length, "too big reg value for stack size");
135 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
136 debug_only( _locs_used[reg->value()] = x; )
137
138 OopMapValue o(reg, x);
139
140 if(x == OopMapValue::callee_saved_value) {
141 // This can never be a stack location, so we don't need to transform it.
142 assert(optional->is_reg(), "Trying to callee save a stack location");
143 o.set_content_reg(optional);
144 } else if(x == OopMapValue::derived_oop_value) {
145 o.set_content_reg(optional);
146 }
147
148 o.write_on(write_stream());
149 increment_count();
150 }
151
152
153 void OopMap::set_oop(VMReg reg) {
154 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
155 }
156
157
158 void OopMap::set_value(VMReg reg) {
159 // At this time, we only need value entries in our OopMap when ZapDeadCompiledLocals is active.
160 if (ZapDeadCompiledLocals)
161 set_xxx(reg, OopMapValue::value_value, VMRegImpl::Bad());
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
203 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
204 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
205
206 if(om_count() >= om_size()) {
207 grow_om_data();
208 }
209 map->set_offset(pc_offset);
210
211 #ifdef ASSERT
212 if(om_count() > 0) {
213 OopMap* last = at(om_count()-1);
214 if (last->offset() == map->offset() ) {
215 fatal("OopMap inserted twice");
216 }
217 if(last->offset() > map->offset()) {
218 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
219 om_count(),last->offset(),om_count()+1,map->offset());
220 }
221 }
222 #endif // ASSERT
223
224 set(om_count(),map);
225 increment_count();
226 }
227
228
229 int OopMapSet::heap_size() const {
230 // The space we use
231 int size = sizeof(OopMap);
232 int align = sizeof(void *) - 1;
233 size = ((size+align) & ~align);
234 size += om_count() * sizeof(OopMap*);
235
236 // Now add in the space needed for the indivdiual OopMaps
237 for(int i=0; i < om_count(); i++) {
238 size += at(i)->heap_size();
239 }
240 // We don't need to align this, it will be naturally pointer aligned
241 return size;
242 }
243
244
245 OopMap* OopMapSet::singular_oop_map() {
246 guarantee(om_count() == 1, "Make sure we only have a single gc point");
247 return at(0);
248 }
249
250
251 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
252 int i, len = om_count();
253 assert( len > 0, "must have pointer maps" );
254
255 // Scan through oopmaps. Stop when current offset is either equal or greater
256 // than the one we are looking for.
257 for( i = 0; i < len; i++) {
258 if( at(i)->offset() >= pc_offset )
259 break;
260 }
261
262 assert( i < len, "oopmap not found" );
263
264 OopMap* m = at(i);
265 assert( m->offset() == pc_offset, "oopmap not found" );
266 return m;
267 }
268
269 class DoNothingClosure: public OopClosure {
270 public:
271 void do_oop(oop* p) {}
272 void do_oop(narrowOop* p) {}
273 };
274 static DoNothingClosure do_nothing;
275
276 static void add_derived_oop(oop* base, oop* derived) {
277 #ifndef TIERED
278 COMPILER1_PRESENT(ShouldNotReachHere();)
279 #endif // TIERED
280 #ifdef COMPILER2
281 DerivedPointerTable::add(derived, base);
282 #endif // COMPILER2
283 }
284
285
286 #ifndef PRODUCT
287 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
288 // Print oopmap and regmap
289 tty->print_cr("------ ");
290 CodeBlob* cb = fr->cb();
291 ImmutableOopMapSet* maps = cb->oop_maps();
292 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
293 map->print();
294 if( cb->is_nmethod() ) {
295 nmethod* nm = (nmethod*)cb;
296 // native wrappers have no scope data, it is implied
297 if (nm->is_native_method()) {
298 tty->print("bci: 0 (native)");
299 } else {
300 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
301 tty->print("bci: %d ",scope->bci());
302 }
303 }
304 tty->cr();
305 fr->print_on(tty);
306 tty->print(" ");
307 cb->print_value_on(tty); tty->cr();
308 reg_map->print();
309 tty->print_cr("------ ");
310
311 }
312 #endif // PRODUCT
313
314 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
315 // add derived oops to a table
316 all_do(fr, reg_map, f, add_derived_oop, &do_nothing);
317 }
318
319
320 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
321 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
322 OopClosure* value_fn) {
323 CodeBlob* cb = fr->cb();
324 assert(cb != NULL, "no codeblob");
325
326 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
327
328 ImmutableOopMapSet* maps = cb->oop_maps();
329 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
330 assert(map != NULL, "no ptr map found");
331
332 // handle derived pointers first (otherwise base pointer may be
333 // changed before derived pointer offset has been collected)
334 OopMapValue omv;
335 {
336 OopMapStream oms(map,OopMapValue::derived_oop_value);
337 if (!oms.is_done()) {
338 #ifndef TIERED
339 COMPILER1_PRESENT(ShouldNotReachHere();)
340 #endif // !TIERED
341 // Protect the operation on the derived pointers. This
342 // protects the addition of derived pointers to the shared
343 // derived pointer table in DerivedPointerTable::add().
344 MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
345 do {
346 omv = oms.current();
347 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
348 if ( loc != NULL ) {
349 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
350 oop *derived_loc = loc;
351 oop val = *base_loc;
352 if (val == (oop)NULL || Universe::is_narrow_oop_base(val)) {
353 // Ignore NULL oops and decoded NULL narrow oops which
354 // equal to Universe::narrow_oop_base when a narrow oop
355 // implicit null check is used in compiled code.
356 // The narrow_oop_base could be NULL or be the address
357 // of the page below heap depending on compressed oops mode.
358 } else
359 derived_oop_fn(base_loc, derived_loc);
360 }
361 oms.next();
362 } while (!oms.is_done());
363 }
364 }
365
366 // We want coop, value and oop oop_types
367 int mask = OopMapValue::oop_value | OopMapValue::value_value | OopMapValue::narrowoop_value;
368 {
369 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
370 omv = oms.current();
371 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
372 if ( loc != NULL ) {
373 if ( omv.type() == OopMapValue::oop_value ) {
374 oop val = *loc;
375 if (val == (oop)NULL || Universe::is_narrow_oop_base(val)) {
376 // Ignore NULL oops and decoded NULL narrow oops which
377 // equal to Universe::narrow_oop_base when a narrow oop
378 // implicit null check is used in compiled code.
379 // The narrow_oop_base could be NULL or be the address
380 // of the page below heap depending on compressed oops mode.
381 continue;
382 }
383 #ifdef ASSERT
384 if ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) ||
385 !Universe::heap()->is_in_or_null(*loc)) {
386 tty->print_cr("# Found non oop pointer. Dumping state at failure");
387 // try to dump out some helpful debugging information
388 trace_codeblob_maps(fr, reg_map);
389 omv.print();
390 tty->print_cr("register r");
391 omv.reg()->print();
392 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
393 // do the real assert.
394 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
395 }
396 #endif // ASSERT
397 oop_fn->do_oop(loc);
398 } else if ( omv.type() == OopMapValue::value_value ) {
399 assert((*loc) == (oop)NULL || !Universe::is_narrow_oop_base(*loc),
400 "found invalid value pointer");
401 value_fn->do_oop(loc);
402 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
403 narrowOop *nl = (narrowOop*)loc;
404 #ifndef VM_LITTLE_ENDIAN
405 if (!omv.reg()->is_stack()) {
406 // compressed oops in registers only take up 4 bytes of an
407 // 8 byte register but they are in the wrong part of the
408 // word so adjust loc to point at the right place.
409 nl = (narrowOop*)((address)nl + 4);
410 }
411 #endif
412 oop_fn->do_oop(nl);
413 }
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_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 #ifndef TIERED
467 COMPILER1_PRESENT(return false);
468 #endif // !TIERED
469 #ifdef COMPILER2
470 OopMapStream oms((OopMap*)this,OopMapValue::derived_oop_value);
471 return oms.is_done();
472 #else
473 return false;
474 #endif // COMPILER2
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::value_value:
489 st->print("Value");
490 break;
491 case OopMapValue::narrowoop_value:
492 st->print("NarrowOop");
493 break;
494 case OopMapValue::callee_saved_value:
495 st->print("Callers_");
496 optional->print_on(st);
497 break;
498 case OopMapValue::derived_oop_value:
499 st->print("Derived_oop_");
500 optional->print_on(st);
501 break;
502 default:
503 ShouldNotReachHere();
504 }
505 }
506
507 void OopMapValue::print_on(outputStream* st) const {
508 reg()->print_on(st);
509 st->print("=");
510 print_register_type(type(),content_reg(),st);
511 st->print(" ");
512 }
513
514 void ImmutableOopMap::print_on(outputStream* st) const {
515 OopMapValue omv;
516 st->print("ImmutableOopMap{");
517 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
518 omv = oms.current();
519 omv.print_on(st);
520 }
521 st->print("}");
522 }
523
524 void OopMap::print_on(outputStream* st) const {
525 OopMapValue omv;
526 st->print("OopMap{");
527 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
528 omv = oms.current();
529 omv.print_on(st);
530 }
531 st->print("off=%d}", (int) offset());
532 }
533
534 void ImmutableOopMapSet::print_on(outputStream* st) const {
535 const ImmutableOopMap* last = NULL;
536 for (int i = 0; i < _count; ++i) {
537 const ImmutableOopMapPair* pair = pair_at(i);
538 const ImmutableOopMap* map = pair->get_from(this);
539 if (map != last) {
540 st->cr();
541 map->print_on(st);
542 st->print("pc offsets: ");
543 }
544 last = map;
545 st->print("%d ", pair->pc_offset());
546 }
547 }
548
549 void OopMapSet::print_on(outputStream* st) const {
550 int i, len = om_count();
551
552 st->print_cr("OopMapSet contains %d OopMaps\n",len);
553
554 for( i = 0; i < len; i++) {
555 OopMap* m = at(i);
556 st->print_cr("#%d ",i);
557 m->print_on(st);
558 st->cr();
559 }
560 }
561
562 bool OopMap::equals(const OopMap* other) const {
563 if (other->_omv_count != _omv_count) {
564 return false;
565 }
566 if (other->write_stream()->position() != write_stream()->position()) {
567 return false;
568 }
569 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
570 return false;
571 }
572 return true;
573 }
574
575 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
576 ImmutableOopMapPair* pairs = get_pairs();
577 ImmutableOopMapPair* last = NULL;
578
579 for (int i = 0; i < _count; ++i) {
580 if (pairs[i].pc_offset() >= pc_offset) {
581 last = &pairs[i];
582 break;
583 }
584 }
585
586 assert(last->pc_offset() == pc_offset, "oopmap not found");
587 return last->get_from(this);
588 }
589
590 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
591 return set->oopmap_at_offset(_oopmap_offset);
592 }
593
594 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
595 address addr = data_addr();
596 oopmap->copy_data_to(addr);
597 }
598
599 #ifdef ASSERT
600 int ImmutableOopMap::nr_of_bytes() const {
601 OopMapStream oms(this);
602
603 while (!oms.is_done()) {
604 oms.next();
605 }
606 return sizeof(ImmutableOopMap) + oms.stream_position();
607 }
608 #endif
609
610 class ImmutableOopMapBuilder {
611 private:
612 class Mapping;
613
614 private:
615 const OopMapSet* _set;
616 const OopMap* _empty;
617 const OopMap* _last;
618 int _empty_offset;
619 int _last_offset;
620 int _offset;
621 Mapping* _mapping;
622 ImmutableOopMapSet* _new_set;
623
624 /* Used for bookkeeping when building ImmutableOopMaps */
625 class Mapping : public ResourceObj {
626 public:
627 enum kind_t { OOPMAP_UNKNOWN = 0, OOPMAP_NEW = 1, OOPMAP_EMPTY = 2, OOPMAP_DUPLICATE = 3 };
628
629 kind_t _kind;
630 int _offset;
631 int _size;
632 const OopMap* _map;
633 const OopMap* _other;
634
635 Mapping() : _kind(OOPMAP_UNKNOWN), _offset(-1), _size(-1), _map(NULL) {}
636
637 void set(kind_t kind, int offset, int size, const OopMap* map = 0, const OopMap* other = 0) {
638 _kind = kind;
639 _offset = offset;
640 _size = size;
641 _map = map;
642 _other = other;
643 }
644 };
645
646 public:
647 ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _new_set(NULL), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0) {
648 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
649 }
650
651 int heap_size();
652 ImmutableOopMapSet* build();
653 private:
654 bool is_empty(const OopMap* map) const {
655 return map->count() == 0;
656 }
657
658 bool is_last_duplicate(const OopMap* map) {
659 if (_last != NULL && _last->count() > 0 && _last->equals(map)) {
660 return true;
661 }
662 return false;
663 }
664
665 #ifdef ASSERT
666 void verify(address buffer, int size, const ImmutableOopMapSet* set);
667 #endif
668
669 bool has_empty() const {
670 return _empty_offset != -1;
671 }
672
673 int size_for(const OopMap* map) const;
674 void fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set);
675 int fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set);
676 void fill(ImmutableOopMapSet* set, int size);
677 };
678
679 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
680 return align_size_up(sizeof(ImmutableOopMap) + map->data_size(), 8);
681 }
682
683 int ImmutableOopMapBuilder::heap_size() {
684 int base = sizeof(ImmutableOopMapSet);
685 base = align_size_up(base, 8);
686
687 // all of ours pc / offset pairs
688 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
689 pairs = align_size_up(pairs, 8);
690
691 for (int i = 0; i < _set->size(); ++i) {
692 int size = 0;
693 OopMap* map = _set->at(i);
694
695 if (is_empty(map)) {
696 /* only keep a single empty map in the set */
697 if (has_empty()) {
698 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
699 } else {
700 _empty_offset = _offset;
701 _empty = map;
702 size = size_for(map);
703 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
704 }
705 } else if (is_last_duplicate(map)) {
706 /* if this entry is identical to the previous one, just point it there */
707 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
708 } else {
709 /* not empty, not an identical copy of the previous entry */
710 size = size_for(map);
711 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
712 _last_offset = _offset;
713 _last = map;
714 }
715
716 assert(_mapping[i]._map == map, "check");
717 _offset += size;
718 }
719
720 int total = base + pairs + _offset;
721 DEBUG_ONLY(total += 8);
722 return total;
723 }
724
725 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
726 assert(offset < set->nr_of_bytes(), "check");
727 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
728 }
729
730 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
731 fill_pair(pair, map, offset, set);
732 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
733
734 new (addr) ImmutableOopMap(map);
735 return align_size_up(sizeof(ImmutableOopMap) + map->data_size(), 8);
736 }
737
738 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
739 ImmutableOopMapPair* pairs = set->get_pairs();
740
741 for (int i = 0; i < set->count(); ++i) {
742 const OopMap* map = _mapping[i]._map;
743 ImmutableOopMapPair* pair = NULL;
744 int size = 0;
745
746 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
747 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
748 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
749 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
750 }
751
752 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
753 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
754 }
755 }
756
757 #ifdef ASSERT
758 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
759 for (int i = 0; i < 8; ++i) {
760 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
761 }
762
763 for (int i = 0; i < set->count(); ++i) {
764 const ImmutableOopMapPair* pair = set->pair_at(i);
765 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
766 const ImmutableOopMap* map = pair->get_from(set);
767 int nr_of_bytes = map->nr_of_bytes();
768 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
769 }
770 }
771 #endif
772
773 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
774 int required = heap_size();
775
776 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
777 address buffer = (address) NEW_C_HEAP_ARRAY(unsigned char, required, mtCode);
778 DEBUG_ONLY(memset(&buffer[required-8], 0xff, 8));
779
780 _new_set = new (buffer) ImmutableOopMapSet(_set, required);
781 fill(_new_set, required);
782
783 DEBUG_ONLY(verify(buffer, required, _new_set));
784
785 return _new_set;
786 }
787
788 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
789 ResourceMark mark;
790 ImmutableOopMapBuilder builder(oopmap_set);
791 return builder.build();
792 }
793
794
795 //------------------------------DerivedPointerTable---------------------------
796
797 #ifdef COMPILER2
798
799 class DerivedPointerEntry : public CHeapObj<mtCompiler> {
800 private:
801 oop* _location; // Location of derived pointer (also pointing to the base)
802 intptr_t _offset; // Offset from base pointer
803 public:
804 DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
805 oop* location() { return _location; }
806 intptr_t offset() { return _offset; }
807 };
808
809
810 GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
811 bool DerivedPointerTable::_active = false;
812
813
814 void DerivedPointerTable::clear() {
815 // The first time, we create the list. Otherwise it should be
816 // empty. If not, then we have probably forgotton to call
817 // update_pointers after last GC/Scavenge.
818 assert (!_active, "should not be active");
819 assert(_list == NULL || _list->length() == 0, "table not empty");
820 if (_list == NULL) {
821 _list = new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
822 }
823 _active = true;
824 }
825
826
827 // Returns value of location as an int
828 intptr_t value_of_loc(oop *pointer) { return cast_from_oop<intptr_t>((*pointer)); }
829
830
831 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
832 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
833 assert(derived_loc != base_loc, "Base and derived in same location");
834 if (_active) {
835 assert(*derived_loc != (oop)base_loc, "location already added");
836 assert(_list != NULL, "list must exist");
837 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
838 // This assert is invalid because derived pointers can be
839 // arbitrarily far away from their base.
840 // assert(offset >= -1000000, "wrong derived pointer info");
841
842 if (TraceDerivedPointers) {
843 tty->print_cr(
844 "Add derived pointer@" INTPTR_FORMAT
845 " - Derived: " INTPTR_FORMAT
846 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
847 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
848 );
849 }
850 // Set derived oop location to point to base.
851 *derived_loc = (oop)base_loc;
852 assert_lock_strong(DerivedPointerTableGC_lock);
853 DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
854 _list->append(entry);
855 }
856 }
857
858
859 void DerivedPointerTable::update_pointers() {
860 assert(_list != NULL, "list must exist");
861 for(int i = 0; i < _list->length(); i++) {
862 DerivedPointerEntry* entry = _list->at(i);
863 oop* derived_loc = entry->location();
864 intptr_t offset = entry->offset();
865 // The derived oop was setup to point to location of base
866 oop base = **(oop**)derived_loc;
867 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
868
869 *derived_loc = (oop)(((address)base) + offset);
870 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
871
872 if (TraceDerivedPointers) {
873 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
874 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
875 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
876 }
877
878 // Delete entry
879 delete entry;
880 _list->at_put(i, NULL);
881 }
882 // Clear list, so it is ready for next traversal (this is an invariant)
883 if (TraceDerivedPointers && !_list->is_empty()) {
884 tty->print_cr("--------------------------");
885 }
886 _list->clear();
887 _active = false;
888 }
889
890 #endif // COMPILER2