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 void OopMapStream::find_next() {
62 while(_position++ < _size) {
63 _omv.read_from(_stream);
64 if(((int)_omv.type() & _mask) > 0) {
65 _valid_omv = true;
66 return;
67 }
68 }
69 _valid_omv = false;
70 }
71
72
73 // OopMap
74
75 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
76 // slots to hold 4-byte values like ints and floats in the LP64 build.
77 OopMap::OopMap(int frame_size, int arg_count) {
78 // OopMaps are usually quite so small, so pick a small initial size
79 set_write_stream(new CompressedWriteStream(32));
80 set_omv_count(0);
81
82 #ifdef ASSERT
83 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
84 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
85 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
86 #endif
87 }
88
89
90 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
91 // This constructor does a deep copy
92 // of the source OopMap.
93 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
94 set_omv_count(0);
95 set_offset(source->offset());
96
97 #ifdef ASSERT
98 _locs_length = source->_locs_length;
99 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
100 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
101 #endif
102
103 // We need to copy the entries too.
104 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
105 OopMapValue omv = oms.current();
106 omv.write_on(write_stream());
107 increment_count();
108 }
109 }
110
111
112 OopMap* OopMap::deep_copy() {
113 return new OopMap(_deep_copy_token, this);
114 }
115
116 void OopMap::copy_data_to(address addr) const {
117 memcpy(addr, write_stream()->buffer(), write_stream()->position());
118 }
119
120 int OopMap::heap_size() const {
121 int size = sizeof(OopMap);
122 int align = sizeof(void *) - 1;
123 size += write_stream()->position();
124 // Align to a reasonable ending point
125 size = ((size+align) & ~align);
126 return size;
127 }
128
129 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
130 // slots to hold 4-byte values like ints and floats in the LP64 build.
131 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
132
133 assert(reg->value() < _locs_length, "too big reg value for stack size");
134 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
135 debug_only( _locs_used[reg->value()] = x; )
136
137 OopMapValue o(reg, x);
138
139 if(x == OopMapValue::callee_saved_value) {
140 // This can never be a stack location, so we don't need to transform it.
141 assert(optional->is_reg(), "Trying to callee save a stack location");
142 o.set_content_reg(optional);
143 } else if(x == OopMapValue::derived_oop_value) {
144 o.set_content_reg(optional);
145 }
146
147 o.write_on(write_stream());
148 increment_count();
149 }
150
151
152 void OopMap::set_oop(VMReg reg) {
153 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
154 }
155
156
157 void OopMap::set_value(VMReg reg) {
158 // At this time, we don't need value entries in our OopMap.
159 }
160
161
162 void OopMap::set_narrowoop(VMReg reg) {
163 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
164 }
165
166
167 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
168 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
169 }
170
171
172 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
173 if( reg == derived_from_local_register ) {
174 // Actually an oop, derived shares storage with base,
175 set_oop(reg);
176 } else {
177 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
178 }
179 }
180
181 // OopMapSet
182
183 OopMapSet::OopMapSet() {
184 set_om_size(MinOopMapAllocation);
185 set_om_count(0);
186 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
187 set_om_data(temp);
188 }
189
190
191 void OopMapSet::grow_om_data() {
192 int new_size = om_size() * 2;
193 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
194 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
195 set_om_size(new_size);
196 set_om_data(new_data);
197 }
198
199 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
200 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
201
202 if(om_count() >= om_size()) {
203 grow_om_data();
204 }
205 map->set_offset(pc_offset);
206
207 #ifdef ASSERT
208 if(om_count() > 0) {
209 OopMap* last = at(om_count()-1);
210 if (last->offset() == map->offset() ) {
211 fatal("OopMap inserted twice");
212 }
213 if(last->offset() > map->offset()) {
214 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
215 om_count(),last->offset(),om_count()+1,map->offset());
216 }
217 }
218 #endif // ASSERT
219
220 set(om_count(),map);
221 increment_count();
222 }
223
224
225 int OopMapSet::heap_size() const {
226 // The space we use
227 int size = sizeof(OopMap);
228 int align = sizeof(void *) - 1;
229 size = ((size+align) & ~align);
230 size += om_count() * sizeof(OopMap*);
231
232 // Now add in the space needed for the indivdiual OopMaps
233 for(int i=0; i < om_count(); i++) {
234 size += at(i)->heap_size();
235 }
236 // We don't need to align this, it will be naturally pointer aligned
237 return size;
238 }
239
240
241 OopMap* OopMapSet::singular_oop_map() {
242 guarantee(om_count() == 1, "Make sure we only have a single gc point");
243 return at(0);
244 }
245
246
247 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
248 int i, len = om_count();
249 assert( len > 0, "must have pointer maps" );
250
251 // Scan through oopmaps. Stop when current offset is either equal or greater
252 // than the one we are looking for.
253 for( i = 0; i < len; i++) {
254 if( at(i)->offset() >= pc_offset )
255 break;
256 }
257
258 assert( i < len, "oopmap not found" );
259
260 OopMap* m = at(i);
261 assert( m->offset() == pc_offset, "oopmap not found" );
262 return m;
263 }
264
265 class DoNothingClosure: public OopClosure {
266 public:
267 void do_oop(oop* p) {}
268 void do_oop(narrowOop* p) {}
269 };
270 static DoNothingClosure do_nothing;
271
272 static void add_derived_oop(oop* base, oop* derived) {
273 #ifndef TIERED
274 COMPILER1_PRESENT(ShouldNotReachHere();)
275 #endif // TIERED
276 #ifdef COMPILER2
277 DerivedPointerTable::add(derived, base);
278 #endif // COMPILER2
279 }
280
281
282 #ifndef PRODUCT
283 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
284 // Print oopmap and regmap
285 tty->print_cr("------ ");
286 CodeBlob* cb = fr->cb();
287 ImmutableOopMapSet* maps = cb->oop_maps();
288 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
289 map->print();
290 if( cb->is_nmethod() ) {
291 nmethod* nm = (nmethod*)cb;
292 // native wrappers have no scope data, it is implied
293 if (nm->is_native_method()) {
294 tty->print("bci: 0 (native)");
295 } else {
296 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
297 tty->print("bci: %d ",scope->bci());
298 }
299 }
300 tty->cr();
301 fr->print_on(tty);
302 tty->print(" ");
303 cb->print_value_on(tty); tty->cr();
304 reg_map->print();
305 tty->print_cr("------ ");
306
307 }
308 #endif // PRODUCT
309
310 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
311 // add derived oops to a table
312 all_do(fr, reg_map, f, add_derived_oop, &do_nothing);
313 }
314
315
316 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
317 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
318 OopClosure* value_fn) {
319 CodeBlob* cb = fr->cb();
320 assert(cb != NULL, "no codeblob");
321
322 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
323
324 ImmutableOopMapSet* maps = cb->oop_maps();
325 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
326 assert(map != NULL, "no ptr map found");
327
328 // handle derived pointers first (otherwise base pointer may be
329 // changed before derived pointer offset has been collected)
330 OopMapValue omv;
331 {
332 OopMapStream oms(map,OopMapValue::derived_oop_value);
333 if (!oms.is_done()) {
334 #ifndef TIERED
335 COMPILER1_PRESENT(ShouldNotReachHere();)
336 #endif // !TIERED
337 // Protect the operation on the derived pointers. This
338 // protects the addition of derived pointers to the shared
339 // derived pointer table in DerivedPointerTable::add().
340 MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
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 *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
346 oop *derived_loc = loc;
347 oop val = *base_loc;
348 if (val == (oop)NULL || Universe::is_narrow_oop_base(val)) {
349 // Ignore NULL oops and decoded NULL narrow oops which
350 // equal to Universe::narrow_oop_base when a narrow oop
351 // implicit null check is used in compiled code.
352 // The narrow_oop_base could be NULL or be the address
353 // of the page below heap depending on compressed oops mode.
354 } else {
355 derived_oop_fn(base_loc, derived_loc);
356 }
357 oms.next();
358 } while (!oms.is_done());
359 }
360 }
361
362 // We want coop, value and oop oop_types
363 int mask = OopMapValue::oop_value | OopMapValue::narrowoop_value;
364 {
365 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
366 omv = oms.current();
367 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
368 // It should be an error if no location can be found for a
369 // register mentioned as contained an oop of some kind. Maybe
370 // this was allowed previously because value_value items might
371 // be missing?
372 guarantee(loc != NULL, "missing saved register");
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::narrowoop_value ) {
399 narrowOop *nl = (narrowOop*)loc;
400 #ifndef VM_LITTLE_ENDIAN
401 VMReg vmReg = omv.reg();
402 // Don't do this on SPARC float registers as they can be individually addressed
403 if (!vmReg->is_stack() SPARC_ONLY(&& !vmReg->is_FloatRegister())) {
404 // compressed oops in registers only take up 4 bytes of an
405 // 8 byte register but they are in the wrong part of the
406 // word so adjust loc to point at the right place.
407 nl = (narrowOop*)((address)nl + 4);
408 }
409 #endif
410 oop_fn->do_oop(nl);
411 }
412 }
413 }
414 }
415
416
417 // Update callee-saved register info for the following frame
418 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
419 ResourceMark rm;
420 CodeBlob* cb = fr->cb();
421 assert(cb != NULL, "no codeblob");
422
423 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
424 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
425 "already updated this map; do not 'update' it twice!" );
426 debug_only(reg_map->_update_for_id = fr->id());
427
428 // Check if caller must update oop argument
429 assert((reg_map->include_argument_oops() ||
430 !cb->caller_must_gc_arguments(reg_map->thread())),
431 "include_argument_oops should already be set");
432
433 // Scan through oopmap and find location of all callee-saved registers
434 // (we do not do update in place, since info could be overwritten)
435
436 address pc = fr->pc();
437 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
438 assert(map != NULL, "no ptr map found");
439 DEBUG_ONLY(int nof_callee = 0;)
440
441 for (OopMapStream oms(map, OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
442 OopMapValue omv = oms.current();
443 VMReg reg = omv.content_reg();
444 oop* loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
445 reg_map->set_location(reg, (address) loc);
446 DEBUG_ONLY(nof_callee++;)
447 }
448
449 // Check that runtime stubs save all callee-saved registers
450 #ifdef COMPILER2
451 assert(cb->is_compiled_by_c1() || !cb->is_runtime_stub() ||
452 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
453 "must save all");
454 #endif // COMPILER2
455 }
456
457 //=============================================================================
458 // Non-Product code
459
460 #ifndef PRODUCT
461
462 bool ImmutableOopMap::has_derived_pointer() const {
463 #ifndef TIERED
464 COMPILER1_PRESENT(return false);
465 #endif // !TIERED
466 #ifdef COMPILER2
467 OopMapStream oms((OopMap*)this,OopMapValue::derived_oop_value);
468 return oms.is_done();
469 #else
470 return false;
471 #endif // COMPILER2
472 }
473
474 #endif //PRODUCT
475
476 // Printing code is present in product build for -XX:+PrintAssembly.
477
478 static
479 void print_register_type(OopMapValue::oop_types x, VMReg optional,
480 outputStream* st) {
481 switch( x ) {
482 case OopMapValue::oop_value:
483 st->print("Oop");
484 break;
485 case OopMapValue::narrowoop_value:
486 st->print("NarrowOop");
487 break;
488 case OopMapValue::callee_saved_value:
489 st->print("Callers_");
490 optional->print_on(st);
491 break;
492 case OopMapValue::derived_oop_value:
493 st->print("Derived_oop_");
494 optional->print_on(st);
495 break;
496 default:
497 ShouldNotReachHere();
498 }
499 }
500
501 void OopMapValue::print_on(outputStream* st) const {
502 reg()->print_on(st);
503 st->print("=");
504 print_register_type(type(),content_reg(),st);
505 st->print(" ");
506 }
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 OopMap::print_on(outputStream* st) const {
519 OopMapValue omv;
520 st->print("OopMap{");
521 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
522 omv = oms.current();
523 omv.print_on(st);
524 }
525 st->print("off=%d}", (int) offset());
526 }
527
528 void ImmutableOopMapSet::print_on(outputStream* st) const {
529 const ImmutableOopMap* last = NULL;
530 for (int i = 0; i < _count; ++i) {
531 const ImmutableOopMapPair* pair = pair_at(i);
532 const ImmutableOopMap* map = pair->get_from(this);
533 if (map != last) {
534 st->cr();
535 map->print_on(st);
536 st->print("pc offsets: ");
537 }
538 last = map;
539 st->print("%d ", pair->pc_offset());
540 }
541 }
542
543 void OopMapSet::print_on(outputStream* st) const {
544 int i, len = om_count();
545
546 st->print_cr("OopMapSet contains %d OopMaps\n",len);
547
548 for( i = 0; i < len; i++) {
549 OopMap* m = at(i);
550 st->print_cr("#%d ",i);
551 m->print_on(st);
552 st->cr();
553 }
554 }
555
556 bool OopMap::equals(const OopMap* other) const {
557 if (other->_omv_count != _omv_count) {
558 return false;
559 }
560 if (other->write_stream()->position() != write_stream()->position()) {
561 return false;
562 }
563 if (memcmp(other->write_stream()->buffer(), write_stream()->buffer(), write_stream()->position()) != 0) {
564 return false;
565 }
566 return true;
567 }
568
569 const ImmutableOopMap* ImmutableOopMapSet::find_map_at_offset(int pc_offset) const {
570 ImmutableOopMapPair* pairs = get_pairs();
571 ImmutableOopMapPair* last = NULL;
572
573 for (int i = 0; i < _count; ++i) {
574 if (pairs[i].pc_offset() >= pc_offset) {
575 last = &pairs[i];
576 break;
577 }
578 }
579
580 assert(last->pc_offset() == pc_offset, "oopmap not found");
581 return last->get_from(this);
582 }
583
584 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
585 return set->oopmap_at_offset(_oopmap_offset);
586 }
587
588 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
589 address addr = data_addr();
590 oopmap->copy_data_to(addr);
591 }
592
593 #ifdef ASSERT
594 int ImmutableOopMap::nr_of_bytes() const {
595 OopMapStream oms(this);
596
597 while (!oms.is_done()) {
598 oms.next();
599 }
600 return sizeof(ImmutableOopMap) + oms.stream_position();
601 }
602 #endif
603
604 class ImmutableOopMapBuilder {
605 private:
606 class Mapping;
607
608 private:
609 const OopMapSet* _set;
610 const OopMap* _empty;
611 const OopMap* _last;
612 int _empty_offset;
613 int _last_offset;
614 int _offset;
615 Mapping* _mapping;
616 ImmutableOopMapSet* _new_set;
617
618 /* Used for bookkeeping when building ImmutableOopMaps */
619 class Mapping : public ResourceObj {
620 public:
621 enum kind_t { OOPMAP_UNKNOWN = 0, OOPMAP_NEW = 1, OOPMAP_EMPTY = 2, OOPMAP_DUPLICATE = 3 };
622
623 kind_t _kind;
624 int _offset;
625 int _size;
626 const OopMap* _map;
627 const OopMap* _other;
628
629 Mapping() : _kind(OOPMAP_UNKNOWN), _offset(-1), _size(-1), _map(NULL) {}
630
631 void set(kind_t kind, int offset, int size, const OopMap* map = 0, const OopMap* other = 0) {
632 _kind = kind;
633 _offset = offset;
634 _size = size;
635 _map = map;
636 _other = other;
637 }
638 };
639
640 public:
641 ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _new_set(NULL), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0) {
642 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
643 }
644
645 int heap_size();
646 ImmutableOopMapSet* build();
647 private:
648 bool is_empty(const OopMap* map) const {
649 return map->count() == 0;
650 }
651
652 bool is_last_duplicate(const OopMap* map) {
653 if (_last != NULL && _last->count() > 0 && _last->equals(map)) {
654 return true;
655 }
656 return false;
657 }
658
659 #ifdef ASSERT
660 void verify(address buffer, int size, const ImmutableOopMapSet* set);
661 #endif
662
663 bool has_empty() const {
664 return _empty_offset != -1;
665 }
666
667 int size_for(const OopMap* map) const;
668 void fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set);
669 int fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set);
670 void fill(ImmutableOopMapSet* set, int size);
671 };
672
673 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
674 return align_size_up(sizeof(ImmutableOopMap) + map->data_size(), 8);
675 }
676
677 int ImmutableOopMapBuilder::heap_size() {
678 int base = sizeof(ImmutableOopMapSet);
679 base = align_size_up(base, 8);
680
681 // all of ours pc / offset pairs
682 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
683 pairs = align_size_up(pairs, 8);
684
685 for (int i = 0; i < _set->size(); ++i) {
686 int size = 0;
687 OopMap* map = _set->at(i);
688
689 if (is_empty(map)) {
690 /* only keep a single empty map in the set */
691 if (has_empty()) {
692 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
693 } else {
694 _empty_offset = _offset;
695 _empty = map;
696 size = size_for(map);
697 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
698 }
699 } else if (is_last_duplicate(map)) {
700 /* if this entry is identical to the previous one, just point it there */
701 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
702 } else {
703 /* not empty, not an identical copy of the previous entry */
704 size = size_for(map);
705 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
706 _last_offset = _offset;
707 _last = map;
708 }
709
710 assert(_mapping[i]._map == map, "check");
711 _offset += size;
712 }
713
714 int total = base + pairs + _offset;
715 DEBUG_ONLY(total += 8);
716 return total;
717 }
718
719 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
720 assert(offset < set->nr_of_bytes(), "check");
721 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
722 }
723
724 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
725 fill_pair(pair, map, offset, set);
726 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
727
728 new (addr) ImmutableOopMap(map);
729 return align_size_up(sizeof(ImmutableOopMap) + map->data_size(), 8);
730 }
731
732 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
733 ImmutableOopMapPair* pairs = set->get_pairs();
734
735 for (int i = 0; i < set->count(); ++i) {
736 const OopMap* map = _mapping[i]._map;
737 ImmutableOopMapPair* pair = NULL;
738 int size = 0;
739
740 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
741 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
742 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
743 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
744 }
745
746 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
747 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
748 }
749 }
750
751 #ifdef ASSERT
752 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
753 for (int i = 0; i < 8; ++i) {
754 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
755 }
756
757 for (int i = 0; i < set->count(); ++i) {
758 const ImmutableOopMapPair* pair = set->pair_at(i);
759 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
760 const ImmutableOopMap* map = pair->get_from(set);
761 int nr_of_bytes = map->nr_of_bytes();
762 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
763 }
764 }
765 #endif
766
767 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
768 int required = heap_size();
769
770 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
771 address buffer = (address) NEW_C_HEAP_ARRAY(unsigned char, required, mtCode);
772 DEBUG_ONLY(memset(&buffer[required-8], 0xff, 8));
773
774 _new_set = new (buffer) ImmutableOopMapSet(_set, required);
775 fill(_new_set, required);
776
777 DEBUG_ONLY(verify(buffer, required, _new_set));
778
779 return _new_set;
780 }
781
782 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
783 ResourceMark mark;
784 ImmutableOopMapBuilder builder(oopmap_set);
785 return builder.build();
786 }
787
788
789 //------------------------------DerivedPointerTable---------------------------
790
791 #ifdef COMPILER2
792
793 class DerivedPointerEntry : public CHeapObj<mtCompiler> {
794 private:
795 oop* _location; // Location of derived pointer (also pointing to the base)
796 intptr_t _offset; // Offset from base pointer
797 public:
798 DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
799 oop* location() { return _location; }
800 intptr_t offset() { return _offset; }
801 };
802
803
804 GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
805 bool DerivedPointerTable::_active = false;
806
807
808 void DerivedPointerTable::clear() {
809 // The first time, we create the list. Otherwise it should be
810 // empty. If not, then we have probably forgotton to call
811 // update_pointers after last GC/Scavenge.
812 assert (!_active, "should not be active");
813 assert(_list == NULL || _list->length() == 0, "table not empty");
814 if (_list == NULL) {
815 _list = new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
816 }
817 _active = true;
818 }
819
820
821 // Returns value of location as an int
822 intptr_t value_of_loc(oop *pointer) { return cast_from_oop<intptr_t>((*pointer)); }
823
824
825 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
826 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
827 assert(derived_loc != base_loc, "Base and derived in same location");
828 if (_active) {
829 assert(*derived_loc != (oop)base_loc, "location already added");
830 assert(_list != NULL, "list must exist");
831 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
832 // This assert is invalid because derived pointers can be
833 // arbitrarily far away from their base.
834 // assert(offset >= -1000000, "wrong derived pointer info");
835
836 if (TraceDerivedPointers) {
837 tty->print_cr(
838 "Add derived pointer@" INTPTR_FORMAT
839 " - Derived: " INTPTR_FORMAT
840 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
841 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
842 );
843 }
844 // Set derived oop location to point to base.
845 *derived_loc = (oop)base_loc;
846 assert_lock_strong(DerivedPointerTableGC_lock);
847 DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
848 _list->append(entry);
849 }
850 }
851
852
853 void DerivedPointerTable::update_pointers() {
854 assert(_list != NULL, "list must exist");
855 for(int i = 0; i < _list->length(); i++) {
856 DerivedPointerEntry* entry = _list->at(i);
857 oop* derived_loc = entry->location();
858 intptr_t offset = entry->offset();
859 // The derived oop was setup to point to location of base
860 oop base = **(oop**)derived_loc;
861 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
862
863 *derived_loc = (oop)(((address)base) + offset);
864 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
865
866 if (TraceDerivedPointers) {
867 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
868 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
869 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
870 }
871
872 // Delete entry
873 delete entry;
874 _list->at_put(i, NULL);
875 }
876 // Clear list, so it is ready for next traversal (this is an invariant)
877 if (TraceDerivedPointers && !_list->is_empty()) {
878 tty->print_cr("--------------------------");
879 }
880 _list->clear();
881 _active = false;
882 }
883
884 #endif // COMPILER2