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 #ifdef COMPILER1
42 #include "c1/c1_Defs.hpp"
43 #endif
44 #ifdef COMPILER2
45 #include "opto/optoreg.hpp"
46 #endif
47
48 // OopMapStream
49
50 OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) {
51 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
52 _mask = oop_types_mask;
53 _size = oop_map->omv_count();
54 _position = 0;
55 _valid_omv = false;
56 }
57
58 OopMapStream::OopMapStream(const ImmutableOopMap* oop_map, int oop_types_mask) {
59 _stream = new CompressedReadStream(oop_map->data_addr());
60 _mask = oop_types_mask;
61 _size = oop_map->count();
62 _position = 0;
63 _valid_omv = false;
64 }
65
66 void OopMapStream::find_next() {
67 while(_position++ < _size) {
68 _omv.read_from(_stream);
69 if(((int)_omv.type() & _mask) > 0) {
70 _valid_omv = true;
71 return;
72 }
73 }
74 _valid_omv = false;
75 }
76
77
78 // OopMap
79
80 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
81 // slots to hold 4-byte values like ints and floats in the LP64 build.
82 OopMap::OopMap(int frame_size, int arg_count) {
83 // OopMaps are usually quite so small, so pick a small initial size
84 set_write_stream(new CompressedWriteStream(32));
85 set_omv_count(0);
86
87 #ifdef ASSERT
88 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
89 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
90 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
91 #endif
92 }
93
94
95 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
96 // This constructor does a deep copy
97 // of the source OopMap.
98 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
99 set_omv_count(0);
100 set_offset(source->offset());
101
102 #ifdef ASSERT
103 _locs_length = source->_locs_length;
104 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
105 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
106 #endif
107
108 // We need to copy the entries too.
109 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
110 OopMapValue omv = oms.current();
111 omv.write_on(write_stream());
112 increment_count();
113 }
114 }
115
116
117 OopMap* OopMap::deep_copy() {
118 return new OopMap(_deep_copy_token, this);
119 }
120
121 void OopMap::copy_data_to(address addr) const {
122 memcpy(addr, write_stream()->buffer(), write_stream()->position());
123 }
124
125 int OopMap::heap_size() const {
126 int size = sizeof(OopMap);
127 int align = sizeof(void *) - 1;
128 size += write_stream()->position();
129 // Align to a reasonable ending point
130 size = ((size+align) & ~align);
131 return size;
132 }
133
134 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
135 // slots to hold 4-byte values like ints and floats in the LP64 build.
136 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
137
138 assert(reg->value() < _locs_length, "too big reg value for stack size");
139 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
140 debug_only( _locs_used[reg->value()] = x; )
141
142 OopMapValue o(reg, x);
143
144 if(x == OopMapValue::callee_saved_value) {
145 // This can never be a stack location, so we don't need to transform it.
146 assert(optional->is_reg(), "Trying to callee save a stack location");
147 o.set_content_reg(optional);
148 } else if(x == OopMapValue::derived_oop_value) {
149 o.set_content_reg(optional);
150 }
151
152 o.write_on(write_stream());
153 increment_count();
154 }
155
156
157 void OopMap::set_oop(VMReg reg) {
158 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
159 }
160
161
162 void OopMap::set_value(VMReg reg) {
163 // At this time, we don't need value entries in our OopMap.
164 }
165
166
167 void OopMap::set_narrowoop(VMReg reg) {
168 set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad());
169 }
170
171
172 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
173 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
174 }
175
176
177 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
178 if( reg == derived_from_local_register ) {
179 // Actually an oop, derived shares storage with base,
180 set_oop(reg);
181 } else {
182 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
183 }
184 }
185
186 // OopMapSet
187
188 OopMapSet::OopMapSet() {
189 set_om_size(MinOopMapAllocation);
190 set_om_count(0);
191 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
192 set_om_data(temp);
193 }
194
195
196 void OopMapSet::grow_om_data() {
197 int new_size = om_size() * 2;
198 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
199 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
200 set_om_size(new_size);
201 set_om_data(new_data);
202 }
203
204 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
205 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
206
207 if(om_count() >= om_size()) {
208 grow_om_data();
209 }
210 map->set_offset(pc_offset);
211
212 #ifdef ASSERT
213 if(om_count() > 0) {
214 OopMap* last = at(om_count()-1);
215 if (last->offset() == map->offset() ) {
216 fatal("OopMap inserted twice");
217 }
218 if(last->offset() > map->offset()) {
219 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
220 om_count(),last->offset(),om_count()+1,map->offset());
221 }
222 }
223 #endif // ASSERT
224
225 set(om_count(),map);
226 increment_count();
227 }
228
229
230 int OopMapSet::heap_size() const {
231 // The space we use
232 int size = sizeof(OopMap);
233 int align = sizeof(void *) - 1;
234 size = ((size+align) & ~align);
235 size += om_count() * sizeof(OopMap*);
236
237 // Now add in the space needed for the indivdiual OopMaps
238 for(int i=0; i < om_count(); i++) {
239 size += at(i)->heap_size();
240 }
241 // We don't need to align this, it will be naturally pointer aligned
242 return size;
243 }
244
245
246 OopMap* OopMapSet::singular_oop_map() {
247 guarantee(om_count() == 1, "Make sure we only have a single gc point");
248 return at(0);
249 }
250
251
252 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
253 int i, len = om_count();
254 assert( len > 0, "must have pointer maps" );
255
256 // Scan through oopmaps. Stop when current offset is either equal or greater
257 // than the one we are looking for.
258 for( i = 0; i < len; i++) {
259 if( at(i)->offset() >= pc_offset )
260 break;
261 }
262
263 assert( i < len, "oopmap not found" );
264
265 OopMap* m = at(i);
266 assert( m->offset() == pc_offset, "oopmap not found" );
267 return m;
268 }
269
270 static void add_derived_oop(oop* base, oop* derived) {
271 #if !defined(TIERED) && !INCLUDE_JVMCI
272 COMPILER1_PRESENT(ShouldNotReachHere();)
273 #endif // !defined(TIERED) && !INCLUDE_JVMCI
274 #if COMPILER2_OR_JVMCI
275 DerivedPointerTable::add(derived, base);
276 #endif // COMPILER2_OR_JVMCI
277 }
278
279
280 #ifndef PRODUCT
281 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
282 // Print oopmap and regmap
283 tty->print_cr("------ ");
284 CodeBlob* cb = fr->cb();
285 const ImmutableOopMapSet* maps = cb->oop_maps();
286 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
287 map->print();
288 if( cb->is_nmethod() ) {
289 nmethod* nm = (nmethod*)cb;
290 // native wrappers have no scope data, it is implied
291 if (nm->is_native_method()) {
292 tty->print("bci: 0 (native)");
293 } else {
294 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
295 tty->print("bci: %d ",scope->bci());
296 }
297 }
298 tty->cr();
299 fr->print_on(tty);
300 tty->print(" ");
301 cb->print_value_on(tty); tty->cr();
302 reg_map->print();
303 tty->print_cr("------ ");
304
305 }
306 #endif // PRODUCT
307
308 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
309 // add derived oops to a table
310 all_do(fr, reg_map, f, add_derived_oop, &do_nothing_cl);
311 }
312
313
314 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
315 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
316 OopClosure* value_fn) {
317 CodeBlob* cb = fr->cb();
318 assert(cb != NULL, "no codeblob");
319
320 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
321
322 const ImmutableOopMapSet* maps = cb->oop_maps();
323 const ImmutableOopMap* map = cb->oop_map_for_return_address(fr->pc());
324 assert(map != NULL, "no ptr map found");
325
326 // handle derived pointers first (otherwise base pointer may be
327 // changed before derived pointer offset has been collected)
328 OopMapValue omv;
329 {
330 OopMapStream oms(map,OopMapValue::derived_oop_value);
331 if (!oms.is_done()) {
332 #ifndef TIERED
333 COMPILER1_PRESENT(ShouldNotReachHere();)
334 #if INCLUDE_JVMCI
335 if (UseJVMCICompiler) {
336 ShouldNotReachHere();
337 }
338 #endif
339 #endif // !TIERED
340 // Protect the operation on the derived pointers. This
341 // protects the addition of derived pointers to the shared
342 // derived pointer table in DerivedPointerTable::add().
343 MutexLocker x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
344 do {
345 omv = oms.current();
346 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
347 guarantee(loc != NULL, "missing saved register");
348 oop *derived_loc = loc;
349 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
350 // Ignore NULL oops and decoded NULL narrow oops which
351 // equal to CompressedOops::base() when a narrow oop
352 // implicit null check is used in compiled code.
353 // The narrow_oop_base could be NULL or be the address
354 // of the page below heap depending on compressed oops mode.
355 if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
356 derived_oop_fn(base_loc, derived_loc);
357 }
358 oms.next();
359 } while (!oms.is_done());
360 }
361 }
362
363 // We want coop and oop oop_types
364 int mask = OopMapValue::oop_value | OopMapValue::narrowoop_value;
365 {
366 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
367 omv = oms.current();
368 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
369 // It should be an error if no location can be found for a
370 // register mentioned as contained an oop of some kind. Maybe
371 // this was allowed previously because value_value items might
372 // be missing?
373 guarantee(loc != NULL, "missing saved register");
374 if ( omv.type() == OopMapValue::oop_value ) {
375 oop val = *loc;
376 if (val == NULL || CompressedOops::is_base(val)) {
377 // Ignore NULL oops and decoded NULL narrow oops which
378 // equal to CompressedOops::base() when a narrow oop
379 // implicit null check is used in compiled code.
380 // The narrow_oop_base could be NULL or be the address
381 // of the page below heap depending on compressed oops mode.
382 continue;
383 }
384 #ifdef ASSERT
385 // We can not verify the oop here if we are using ZGC, the oop
386 // will be bad in case we had a safepoint between a load and a
387 // load barrier.
388 if (!UseZGC &&
389 ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) ||
390 !Universe::heap()->is_in_or_null(*loc))) {
391 tty->print_cr("# Found non oop pointer. Dumping state at failure");
392 // try to dump out some helpful debugging information
393 trace_codeblob_maps(fr, reg_map);
394 omv.print();
395 tty->print_cr("register r");
396 omv.reg()->print();
397 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
398 // do the real assert.
399 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
400 }
401 #endif // ASSERT
402 oop_fn->do_oop(loc);
403 } else if ( omv.type() == OopMapValue::narrowoop_value ) {
404 narrowOop *nl = (narrowOop*)loc;
405 #ifndef VM_LITTLE_ENDIAN
406 VMReg vmReg = omv.reg();
407 // Don't do this on SPARC float registers as they can be individually addressed
408 if (!vmReg->is_stack() SPARC_ONLY(&& !vmReg->is_FloatRegister())) {
409 // compressed oops in registers only take up 4 bytes of an
410 // 8 byte register but they are in the wrong part of the
411 // word so adjust loc to point at the right place.
412 nl = (narrowOop*)((address)nl + 4);
413 }
414 #endif
415 oop_fn->do_oop(nl);
416 }
417 }
418 }
419 }
420
421
422 // Update callee-saved register info for the following frame
423 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
424 ResourceMark rm;
425 CodeBlob* cb = fr->cb();
426 assert(cb != NULL, "no codeblob");
427
428 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
429 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
430 "already updated this map; do not 'update' it twice!" );
431 debug_only(reg_map->_update_for_id = fr->id());
432
433 // Check if caller must update oop argument
434 assert((reg_map->include_argument_oops() ||
435 !cb->caller_must_gc_arguments(reg_map->thread())),
436 "include_argument_oops should already be set");
437
438 // Scan through oopmap and find location of all callee-saved registers
439 // (we do not do update in place, since info could be overwritten)
440
441 address pc = fr->pc();
442 const ImmutableOopMap* map = cb->oop_map_for_return_address(pc);
443 assert(map != NULL, "no ptr map found");
444 DEBUG_ONLY(int nof_callee = 0;)
445
446 for (OopMapStream oms(map, OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
447 OopMapValue omv = oms.current();
448 VMReg reg = omv.content_reg();
449 oop* loc = fr->oopmapreg_to_location(omv.reg(), reg_map);
450 reg_map->set_location(reg, (address) loc);
451 DEBUG_ONLY(nof_callee++;)
452 }
453
454 // Check that runtime stubs save all callee-saved registers
455 #ifdef COMPILER2
456 assert(cb->is_compiled_by_c1() || cb->is_compiled_by_jvmci() || !cb->is_runtime_stub() ||
457 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
458 "must save all");
459 #endif // COMPILER2
460 }
461
462 //=============================================================================
463 // Non-Product code
464
465 #ifndef PRODUCT
466
467 bool ImmutableOopMap::has_derived_pointer() const {
468 #if !defined(TIERED) && !INCLUDE_JVMCI
469 COMPILER1_PRESENT(return false);
470 #endif // !TIERED
471 #if COMPILER2_OR_JVMCI
472 OopMapStream oms(this,OopMapValue::derived_oop_value);
473 return oms.is_done();
474 #else
475 return false;
476 #endif // COMPILER2_OR_JVMCI
477 }
478
479 #endif //PRODUCT
480
481 // Printing code is present in product build for -XX:+PrintAssembly.
482
483 static
484 void print_register_type(OopMapValue::oop_types x, VMReg optional,
485 outputStream* st) {
486 switch( x ) {
487 case OopMapValue::oop_value:
488 st->print("Oop");
489 break;
490 case OopMapValue::narrowoop_value:
491 st->print("NarrowOop");
492 break;
493 case OopMapValue::callee_saved_value:
494 st->print("Callers_");
495 optional->print_on(st);
496 break;
497 case OopMapValue::derived_oop_value:
498 st->print("Derived_oop_");
499 optional->print_on(st);
500 break;
501 default:
502 ShouldNotReachHere();
503 }
504 }
505
506 void OopMapValue::print_on(outputStream* st) const {
507 reg()->print_on(st);
508 st->print("=");
509 print_register_type(type(),content_reg(),st);
510 st->print(" ");
511 }
512
513 void OopMapValue::print() const { print_on(tty); }
514
515 void ImmutableOopMap::print_on(outputStream* st) const {
516 OopMapValue omv;
517 st->print("ImmutableOopMap{");
518 for(OopMapStream oms(this); !oms.is_done(); oms.next()) {
519 omv = oms.current();
520 omv.print_on(st);
521 }
522 st->print("}");
523 }
524
525 void ImmutableOopMap::print() const { print_on(tty); }
526
527 void OopMap::print_on(outputStream* st) const {
528 OopMapValue omv;
529 st->print("OopMap{");
530 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
531 omv = oms.current();
532 omv.print_on(st);
533 }
534 st->print("off=%d}", (int) offset());
535 }
536
537 void OopMap::print() const { print_on(tty); }
538
539 void ImmutableOopMapSet::print_on(outputStream* st) const {
540 const ImmutableOopMap* last = NULL;
541 for (int i = 0; i < _count; ++i) {
542 const ImmutableOopMapPair* pair = pair_at(i);
543 const ImmutableOopMap* map = pair->get_from(this);
544 if (map != last) {
545 st->cr();
546 map->print_on(st);
547 st->print("pc offsets: ");
548 }
549 last = map;
550 st->print("%d ", pair->pc_offset());
551 }
552 }
553
554 void ImmutableOopMapSet::print() const { print_on(tty); }
555
556 void OopMapSet::print_on(outputStream* st) const {
557 int i, len = om_count();
558
559 st->print_cr("OopMapSet contains %d OopMaps\n",len);
560
561 for( i = 0; i < len; i++) {
562 OopMap* m = at(i);
563 st->print_cr("#%d ",i);
564 m->print_on(st);
565 st->cr();
566 }
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
587 int i;
588 for (i = 0; i < _count; ++i) {
589 if (pairs[i].pc_offset() >= pc_offset) {
590 break;
591 }
592 }
593 ImmutableOopMapPair* last = &pairs[i];
594
595 assert(last->pc_offset() == pc_offset, "oopmap not found");
596 return last->get_from(this);
597 }
598
599 const ImmutableOopMap* ImmutableOopMapPair::get_from(const ImmutableOopMapSet* set) const {
600 return set->oopmap_at_offset(_oopmap_offset);
601 }
602
603 ImmutableOopMap::ImmutableOopMap(const OopMap* oopmap) : _count(oopmap->count()) {
604 address addr = data_addr();
605 oopmap->copy_data_to(addr);
606 }
607
608 #ifdef ASSERT
609 int ImmutableOopMap::nr_of_bytes() const {
610 OopMapStream oms(this);
611
612 while (!oms.is_done()) {
613 oms.next();
614 }
615 return sizeof(ImmutableOopMap) + oms.stream_position();
616 }
617 #endif
618
619 ImmutableOopMapBuilder::ImmutableOopMapBuilder(const OopMapSet* set) : _set(set), _empty(NULL), _last(NULL), _empty_offset(-1), _last_offset(-1), _offset(0), _required(-1), _new_set(NULL) {
620 _mapping = NEW_RESOURCE_ARRAY(Mapping, _set->size());
621 }
622
623 int ImmutableOopMapBuilder::size_for(const OopMap* map) const {
624 return align_up((int)sizeof(ImmutableOopMap) + map->data_size(), 8);
625 }
626
627 int ImmutableOopMapBuilder::heap_size() {
628 int base = sizeof(ImmutableOopMapSet);
629 base = align_up(base, 8);
630
631 // all of ours pc / offset pairs
632 int pairs = _set->size() * sizeof(ImmutableOopMapPair);
633 pairs = align_up(pairs, 8);
634
635 for (int i = 0; i < _set->size(); ++i) {
636 int size = 0;
637 OopMap* map = _set->at(i);
638
639 if (is_empty(map)) {
640 /* only keep a single empty map in the set */
641 if (has_empty()) {
642 _mapping[i].set(Mapping::OOPMAP_EMPTY, _empty_offset, 0, map, _empty);
643 } else {
644 _empty_offset = _offset;
645 _empty = map;
646 size = size_for(map);
647 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
648 }
649 } else if (is_last_duplicate(map)) {
650 /* if this entry is identical to the previous one, just point it there */
651 _mapping[i].set(Mapping::OOPMAP_DUPLICATE, _last_offset, 0, map, _last);
652 } else {
653 /* not empty, not an identical copy of the previous entry */
654 size = size_for(map);
655 _mapping[i].set(Mapping::OOPMAP_NEW, _offset, size, map);
656 _last_offset = _offset;
657 _last = map;
658 }
659
660 assert(_mapping[i]._map == map, "check");
661 _offset += size;
662 }
663
664 int total = base + pairs + _offset;
665 DEBUG_ONLY(total += 8);
666 _required = total;
667 return total;
668 }
669
670 void ImmutableOopMapBuilder::fill_pair(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
671 assert(offset < set->nr_of_bytes(), "check");
672 new ((address) pair) ImmutableOopMapPair(map->offset(), offset);
673 }
674
675 int ImmutableOopMapBuilder::fill_map(ImmutableOopMapPair* pair, const OopMap* map, int offset, const ImmutableOopMapSet* set) {
676 fill_pair(pair, map, offset, set);
677 address addr = (address) pair->get_from(_new_set); // location of the ImmutableOopMap
678
679 new (addr) ImmutableOopMap(map);
680 return size_for(map);
681 }
682
683 void ImmutableOopMapBuilder::fill(ImmutableOopMapSet* set, int sz) {
684 ImmutableOopMapPair* pairs = set->get_pairs();
685
686 for (int i = 0; i < set->count(); ++i) {
687 const OopMap* map = _mapping[i]._map;
688 ImmutableOopMapPair* pair = NULL;
689 int size = 0;
690
691 if (_mapping[i]._kind == Mapping::OOPMAP_NEW) {
692 size = fill_map(&pairs[i], map, _mapping[i]._offset, set);
693 } else if (_mapping[i]._kind == Mapping::OOPMAP_DUPLICATE || _mapping[i]._kind == Mapping::OOPMAP_EMPTY) {
694 fill_pair(&pairs[i], map, _mapping[i]._offset, set);
695 }
696
697 const ImmutableOopMap* nv = set->find_map_at_offset(map->offset());
698 assert(memcmp(map->data(), nv->data_addr(), map->data_size()) == 0, "check identity");
699 }
700 }
701
702 #ifdef ASSERT
703 void ImmutableOopMapBuilder::verify(address buffer, int size, const ImmutableOopMapSet* set) {
704 for (int i = 0; i < 8; ++i) {
705 assert(buffer[size - 8 + i] == (unsigned char) 0xff, "overwritten memory check");
706 }
707
708 for (int i = 0; i < set->count(); ++i) {
709 const ImmutableOopMapPair* pair = set->pair_at(i);
710 assert(pair->oopmap_offset() < set->nr_of_bytes(), "check size");
711 const ImmutableOopMap* map = pair->get_from(set);
712 int nr_of_bytes = map->nr_of_bytes();
713 assert(pair->oopmap_offset() + nr_of_bytes <= set->nr_of_bytes(), "check size + size");
714 }
715 }
716 #endif
717
718 ImmutableOopMapSet* ImmutableOopMapBuilder::generate_into(address buffer) {
719 DEBUG_ONLY(memset(&buffer[_required-8], 0xff, 8));
720
721 _new_set = new (buffer) ImmutableOopMapSet(_set, _required);
722 fill(_new_set, _required);
723
724 DEBUG_ONLY(verify(buffer, _required, _new_set));
725
726 return _new_set;
727 }
728
729 ImmutableOopMapSet* ImmutableOopMapBuilder::build() {
730 _required = heap_size();
731
732 // We need to allocate a chunk big enough to hold the ImmutableOopMapSet and all of its ImmutableOopMaps
733 address buffer = (address) NEW_C_HEAP_ARRAY(unsigned char, _required, mtCode);
734 return generate_into(buffer);
735 }
736
737 ImmutableOopMapSet* ImmutableOopMapSet::build_from(const OopMapSet* oopmap_set) {
738 ResourceMark mark;
739 ImmutableOopMapBuilder builder(oopmap_set);
740 return builder.build();
741 }
742
743
744 //------------------------------DerivedPointerTable---------------------------
745
746 #if COMPILER2_OR_JVMCI
747
748 class DerivedPointerEntry : public CHeapObj<mtCompiler> {
749 private:
750 oop* _location; // Location of derived pointer (also pointing to the base)
751 intptr_t _offset; // Offset from base pointer
752 public:
753 DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
754 oop* location() { return _location; }
755 intptr_t offset() { return _offset; }
756 };
757
758
759 GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
760 bool DerivedPointerTable::_active = false;
761
762
763 void DerivedPointerTable::clear() {
764 // The first time, we create the list. Otherwise it should be
765 // empty. If not, then we have probably forgotton to call
766 // update_pointers after last GC/Scavenge.
767 assert (!_active, "should not be active");
768 assert(_list == NULL || _list->length() == 0, "table not empty");
769 if (_list == NULL) {
770 _list = new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
771 }
772 _active = true;
773 }
774
775
776 // Returns value of location as an int
777 intptr_t value_of_loc(oop *pointer) { return cast_from_oop<intptr_t>((*pointer)); }
778
779
780 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
781 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
782 assert(derived_loc != base_loc, "Base and derived in same location");
783 if (_active) {
784 assert(*derived_loc != (void*)base_loc, "location already added");
785 assert(_list != NULL, "list must exist");
786 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
787 // This assert is invalid because derived pointers can be
788 // arbitrarily far away from their base.
789 // assert(offset >= -1000000, "wrong derived pointer info");
790
791 if (TraceDerivedPointers) {
792 tty->print_cr(
793 "Add derived pointer@" INTPTR_FORMAT
794 " - Derived: " INTPTR_FORMAT
795 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: " INTX_FORMAT ")",
796 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)*base_loc), p2i(base_loc), offset
797 );
798 }
799 // Set derived oop location to point to base.
800 *derived_loc = (oop)base_loc;
801 assert_lock_strong(DerivedPointerTableGC_lock);
802 DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
803 _list->append(entry);
804 }
805 }
806
807
808 void DerivedPointerTable::update_pointers() {
809 assert(_list != NULL, "list must exist");
810 for(int i = 0; i < _list->length(); i++) {
811 DerivedPointerEntry* entry = _list->at(i);
812 oop* derived_loc = entry->location();
813 intptr_t offset = entry->offset();
814 // The derived oop was setup to point to location of base
815 oop base = **(oop**)derived_loc;
816 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
817
818 *derived_loc = (oop)(((address)base) + offset);
819 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
820
821 if (TraceDerivedPointers) {
822 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
823 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: " INTX_FORMAT ")",
824 p2i(derived_loc), p2i((address)*derived_loc), p2i((address)base), offset);
825 }
826
827 // Delete entry
828 delete entry;
829 _list->at_put(i, NULL);
830 }
831 // Clear list, so it is ready for next traversal (this is an invariant)
832 if (TraceDerivedPointers && !_list->is_empty()) {
833 tty->print_cr("--------------------------");
834 }
835 _list->clear();
836 _active = false;
837 }
838
839 #endif // COMPILER2_OR_JVMCI