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 MutexLocker 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