1 /* 2 * Copyright (c) 1997, 2013, 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/codeCache.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/dependencies.hpp" 29 #include "code/nmethod.hpp" 30 #include "code/scopeDesc.hpp" 31 #include "compiler/abstractCompiler.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "compiler/compileLog.hpp" 34 #include "compiler/compilerOracle.hpp" 35 #include "compiler/disassembler.hpp" 36 #include "interpreter/bytecode.hpp" 37 #include "oops/methodData.hpp" 38 #include "prims/jvmtiRedefineClassesTrace.hpp" 39 #include "prims/jvmtiImpl.hpp" 40 #include "runtime/sharedRuntime.hpp" 41 #include "runtime/sweeper.hpp" 42 #include "utilities/dtrace.hpp" 43 #include "utilities/events.hpp" 44 #include "utilities/xmlstream.hpp" 45 #ifdef SHARK 46 #include "shark/sharkCompiler.hpp" 47 #endif 48 49 #ifdef DTRACE_ENABLED 50 51 // Only bother with this argument setup if dtrace is available 52 53 #ifndef USDT2 54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load, 55 const char*, int, const char*, int, const char*, int, void*, size_t); 56 57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload, 58 char*, int, char*, int, char*, int); 59 60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 61 { \ 62 Method* m = (method); \ 63 if (m != NULL) { \ 64 Symbol* klass_name = m->klass_name(); \ 65 Symbol* name = m->name(); \ 66 Symbol* signature = m->signature(); \ 67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \ 68 klass_name->bytes(), klass_name->utf8_length(), \ 69 name->bytes(), name->utf8_length(), \ 70 signature->bytes(), signature->utf8_length()); \ 71 } \ 72 } 73 #else /* USDT2 */ 74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 75 { \ 76 Method* m = (method); \ 77 if (m != NULL) { \ 78 Symbol* klass_name = m->klass_name(); \ 79 Symbol* name = m->name(); \ 80 Symbol* signature = m->signature(); \ 81 HOTSPOT_COMPILED_METHOD_UNLOAD( \ 82 (char *) klass_name->bytes(), klass_name->utf8_length(), \ 83 (char *) name->bytes(), name->utf8_length(), \ 84 (char *) signature->bytes(), signature->utf8_length()); \ 85 } \ 86 } 87 #endif /* USDT2 */ 88 89 #else // ndef DTRACE_ENABLED 90 91 #define DTRACE_METHOD_UNLOAD_PROBE(method) 92 93 #endif 94 95 bool nmethod::is_compiled_by_c1() const { 96 if (compiler() == NULL) { 97 return false; 98 } 99 return compiler()->is_c1(); 100 } 101 bool nmethod::is_compiled_by_c2() const { 102 if (compiler() == NULL) { 103 return false; 104 } 105 return compiler()->is_c2(); 106 } 107 bool nmethod::is_compiled_by_shark() const { 108 if (compiler() == NULL) { 109 return false; 110 } 111 return compiler()->is_shark(); 112 } 113 114 115 116 //--------------------------------------------------------------------------------- 117 // NMethod statistics 118 // They are printed under various flags, including: 119 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation. 120 // (In the latter two cases, they like other stats are printed to the log only.) 121 122 #ifndef PRODUCT 123 // These variables are put into one block to reduce relocations 124 // and make it simpler to print from the debugger. 125 static 126 struct nmethod_stats_struct { 127 int nmethod_count; 128 int total_size; 129 int relocation_size; 130 int consts_size; 131 int insts_size; 132 int stub_size; 133 int scopes_data_size; 134 int scopes_pcs_size; 135 int dependencies_size; 136 int handler_table_size; 137 int nul_chk_table_size; 138 int oops_size; 139 140 void note_nmethod(nmethod* nm) { 141 nmethod_count += 1; 142 total_size += nm->size(); 143 relocation_size += nm->relocation_size(); 144 consts_size += nm->consts_size(); 145 insts_size += nm->insts_size(); 146 stub_size += nm->stub_size(); 147 oops_size += nm->oops_size(); 148 scopes_data_size += nm->scopes_data_size(); 149 scopes_pcs_size += nm->scopes_pcs_size(); 150 dependencies_size += nm->dependencies_size(); 151 handler_table_size += nm->handler_table_size(); 152 nul_chk_table_size += nm->nul_chk_table_size(); 153 } 154 void print_nmethod_stats() { 155 if (nmethod_count == 0) return; 156 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count); 157 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size); 158 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size); 159 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size); 160 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size); 161 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size); 162 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size); 163 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size); 164 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size); 165 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size); 166 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size); 167 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size); 168 } 169 170 int native_nmethod_count; 171 int native_total_size; 172 int native_relocation_size; 173 int native_insts_size; 174 int native_oops_size; 175 void note_native_nmethod(nmethod* nm) { 176 native_nmethod_count += 1; 177 native_total_size += nm->size(); 178 native_relocation_size += nm->relocation_size(); 179 native_insts_size += nm->insts_size(); 180 native_oops_size += nm->oops_size(); 181 } 182 void print_native_nmethod_stats() { 183 if (native_nmethod_count == 0) return; 184 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count); 185 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size); 186 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size); 187 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size); 188 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size); 189 } 190 191 int pc_desc_resets; // number of resets (= number of caches) 192 int pc_desc_queries; // queries to nmethod::find_pc_desc 193 int pc_desc_approx; // number of those which have approximate true 194 int pc_desc_repeats; // number of _pc_descs[0] hits 195 int pc_desc_hits; // number of LRU cache hits 196 int pc_desc_tests; // total number of PcDesc examinations 197 int pc_desc_searches; // total number of quasi-binary search steps 198 int pc_desc_adds; // number of LUR cache insertions 199 200 void print_pc_stats() { 201 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query", 202 pc_desc_queries, 203 (double)(pc_desc_tests + pc_desc_searches) 204 / pc_desc_queries); 205 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d", 206 pc_desc_resets, 207 pc_desc_queries, pc_desc_approx, 208 pc_desc_repeats, pc_desc_hits, 209 pc_desc_tests, pc_desc_searches, pc_desc_adds); 210 } 211 } nmethod_stats; 212 #endif //PRODUCT 213 214 215 //--------------------------------------------------------------------------------- 216 217 218 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) { 219 assert(pc != NULL, "Must be non null"); 220 assert(exception.not_null(), "Must be non null"); 221 assert(handler != NULL, "Must be non null"); 222 223 _count = 0; 224 _exception_type = exception->klass(); 225 _next = NULL; 226 227 add_address_and_handler(pc,handler); 228 } 229 230 231 address ExceptionCache::match(Handle exception, address pc) { 232 assert(pc != NULL,"Must be non null"); 233 assert(exception.not_null(),"Must be non null"); 234 if (exception->klass() == exception_type()) { 235 return (test_address(pc)); 236 } 237 238 return NULL; 239 } 240 241 242 bool ExceptionCache::match_exception_with_space(Handle exception) { 243 assert(exception.not_null(),"Must be non null"); 244 if (exception->klass() == exception_type() && count() < cache_size) { 245 return true; 246 } 247 return false; 248 } 249 250 251 address ExceptionCache::test_address(address addr) { 252 for (int i=0; i<count(); i++) { 253 if (pc_at(i) == addr) { 254 return handler_at(i); 255 } 256 } 257 return NULL; 258 } 259 260 261 bool ExceptionCache::add_address_and_handler(address addr, address handler) { 262 if (test_address(addr) == handler) return true; 263 if (count() < cache_size) { 264 set_pc_at(count(),addr); 265 set_handler_at(count(), handler); 266 increment_count(); 267 return true; 268 } 269 return false; 270 } 271 272 273 // private method for handling exception cache 274 // These methods are private, and used to manipulate the exception cache 275 // directly. 276 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) { 277 ExceptionCache* ec = exception_cache(); 278 while (ec != NULL) { 279 if (ec->match_exception_with_space(exception)) { 280 return ec; 281 } 282 ec = ec->next(); 283 } 284 return NULL; 285 } 286 287 288 //----------------------------------------------------------------------------- 289 290 291 // Helper used by both find_pc_desc methods. 292 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) { 293 NOT_PRODUCT(++nmethod_stats.pc_desc_tests); 294 if (!approximate) 295 return pc->pc_offset() == pc_offset; 296 else 297 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset(); 298 } 299 300 void PcDescCache::reset_to(PcDesc* initial_pc_desc) { 301 if (initial_pc_desc == NULL) { 302 _pc_descs[0] = NULL; // native method; no PcDescs at all 303 return; 304 } 305 NOT_PRODUCT(++nmethod_stats.pc_desc_resets); 306 // reset the cache by filling it with benign (non-null) values 307 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel"); 308 for (int i = 0; i < cache_size; i++) 309 _pc_descs[i] = initial_pc_desc; 310 } 311 312 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) { 313 NOT_PRODUCT(++nmethod_stats.pc_desc_queries); 314 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx); 315 316 // Note: one might think that caching the most recently 317 // read value separately would be a win, but one would be 318 // wrong. When many threads are updating it, the cache 319 // line it's in would bounce between caches, negating 320 // any benefit. 321 322 // In order to prevent race conditions do not load cache elements 323 // repeatedly, but use a local copy: 324 PcDesc* res; 325 326 // Step one: Check the most recently added value. 327 res = _pc_descs[0]; 328 if (res == NULL) return NULL; // native method; no PcDescs at all 329 if (match_desc(res, pc_offset, approximate)) { 330 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats); 331 return res; 332 } 333 334 // Step two: Check the rest of the LRU cache. 335 for (int i = 1; i < cache_size; ++i) { 336 res = _pc_descs[i]; 337 if (res->pc_offset() < 0) break; // optimization: skip empty cache 338 if (match_desc(res, pc_offset, approximate)) { 339 NOT_PRODUCT(++nmethod_stats.pc_desc_hits); 340 return res; 341 } 342 } 343 344 // Report failure. 345 return NULL; 346 } 347 348 void PcDescCache::add_pc_desc(PcDesc* pc_desc) { 349 NOT_PRODUCT(++nmethod_stats.pc_desc_adds); 350 // Update the LRU cache by shifting pc_desc forward. 351 for (int i = 0; i < cache_size; i++) { 352 PcDesc* next = _pc_descs[i]; 353 _pc_descs[i] = pc_desc; 354 pc_desc = next; 355 } 356 } 357 358 // adjust pcs_size so that it is a multiple of both oopSize and 359 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple 360 // of oopSize, then 2*sizeof(PcDesc) is) 361 static int adjust_pcs_size(int pcs_size) { 362 int nsize = round_to(pcs_size, oopSize); 363 if ((nsize % sizeof(PcDesc)) != 0) { 364 nsize = pcs_size + sizeof(PcDesc); 365 } 366 assert((nsize % oopSize) == 0, "correct alignment"); 367 return nsize; 368 } 369 370 //----------------------------------------------------------------------------- 371 372 373 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) { 374 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock"); 375 assert(new_entry != NULL,"Must be non null"); 376 assert(new_entry->next() == NULL, "Must be null"); 377 378 if (exception_cache() != NULL) { 379 new_entry->set_next(exception_cache()); 380 } 381 set_exception_cache(new_entry); 382 } 383 384 void nmethod::remove_from_exception_cache(ExceptionCache* ec) { 385 ExceptionCache* prev = NULL; 386 ExceptionCache* curr = exception_cache(); 387 assert(curr != NULL, "nothing to remove"); 388 // find the previous and next entry of ec 389 while (curr != ec) { 390 prev = curr; 391 curr = curr->next(); 392 assert(curr != NULL, "ExceptionCache not found"); 393 } 394 // now: curr == ec 395 ExceptionCache* next = curr->next(); 396 if (prev == NULL) { 397 set_exception_cache(next); 398 } else { 399 prev->set_next(next); 400 } 401 delete curr; 402 } 403 404 405 // public method for accessing the exception cache 406 // These are the public access methods. 407 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) { 408 // We never grab a lock to read the exception cache, so we may 409 // have false negatives. This is okay, as it can only happen during 410 // the first few exception lookups for a given nmethod. 411 ExceptionCache* ec = exception_cache(); 412 while (ec != NULL) { 413 address ret_val; 414 if ((ret_val = ec->match(exception,pc)) != NULL) { 415 return ret_val; 416 } 417 ec = ec->next(); 418 } 419 return NULL; 420 } 421 422 423 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) { 424 // There are potential race conditions during exception cache updates, so we 425 // must own the ExceptionCache_lock before doing ANY modifications. Because 426 // we don't lock during reads, it is possible to have several threads attempt 427 // to update the cache with the same data. We need to check for already inserted 428 // copies of the current data before adding it. 429 430 MutexLocker ml(ExceptionCache_lock); 431 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception); 432 433 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) { 434 target_entry = new ExceptionCache(exception,pc,handler); 435 add_exception_cache_entry(target_entry); 436 } 437 } 438 439 440 //-------------end of code for ExceptionCache-------------- 441 442 443 int nmethod::total_size() const { 444 return 445 consts_size() + 446 insts_size() + 447 stub_size() + 448 scopes_data_size() + 449 scopes_pcs_size() + 450 handler_table_size() + 451 nul_chk_table_size(); 452 } 453 454 const char* nmethod::compile_kind() const { 455 if (is_osr_method()) return "osr"; 456 if (method() != NULL && is_native_method()) return "c2n"; 457 return NULL; 458 } 459 460 // Fill in default values for various flag fields 461 void nmethod::init_defaults() { 462 _state = alive; 463 _marked_for_reclamation = 0; 464 _has_flushed_dependencies = 0; 465 _has_unsafe_access = 0; 466 _has_method_handle_invokes = 0; 467 _lazy_critical_native = 0; 468 _has_wide_vectors = 0; 469 _marked_for_deoptimization = 0; 470 _lock_count = 0; 471 _stack_traversal_mark = 0; 472 _unload_reported = false; // jvmti state 473 474 #ifdef ASSERT 475 _oops_are_stale = false; 476 #endif 477 478 _oops_do_mark_link = NULL; 479 _jmethod_id = NULL; 480 _osr_link = NULL; 481 _scavenge_root_link = NULL; 482 _scavenge_root_state = 0; 483 _compiler = NULL; 484 485 #ifdef HAVE_DTRACE_H 486 _trap_offset = 0; 487 #endif // def HAVE_DTRACE_H 488 } 489 490 nmethod* nmethod::new_native_nmethod(methodHandle method, 491 int compile_id, 492 CodeBuffer *code_buffer, 493 int vep_offset, 494 int frame_complete, 495 int frame_size, 496 ByteSize basic_lock_owner_sp_offset, 497 ByteSize basic_lock_sp_offset, 498 OopMapSet* oop_maps) { 499 code_buffer->finalize_oop_references(method); 500 // create nmethod 501 nmethod* nm = NULL; 502 { 503 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 504 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 505 CodeOffsets offsets; 506 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 507 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 508 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size, 509 compile_id, &offsets, 510 code_buffer, frame_size, 511 basic_lock_owner_sp_offset, 512 basic_lock_sp_offset, oop_maps); 513 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm)); 514 if (PrintAssembly && nm != NULL) { 515 Disassembler::decode(nm); 516 } 517 } 518 // verify nmethod 519 debug_only(if (nm) nm->verify();) // might block 520 521 if (nm != NULL) { 522 nm->log_new_nmethod(); 523 } 524 525 return nm; 526 } 527 528 #ifdef HAVE_DTRACE_H 529 nmethod* nmethod::new_dtrace_nmethod(methodHandle method, 530 CodeBuffer *code_buffer, 531 int vep_offset, 532 int trap_offset, 533 int frame_complete, 534 int frame_size) { 535 code_buffer->finalize_oop_references(method); 536 // create nmethod 537 nmethod* nm = NULL; 538 { 539 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 540 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 541 CodeOffsets offsets; 542 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 543 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset); 544 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 545 546 nm = new (nmethod_size) nmethod(method(), nmethod_size, 547 &offsets, code_buffer, frame_size); 548 549 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); 550 if (PrintAssembly && nm != NULL) { 551 Disassembler::decode(nm); 552 } 553 } 554 // verify nmethod 555 debug_only(if (nm) nm->verify();) // might block 556 557 if (nm != NULL) { 558 nm->log_new_nmethod(); 559 } 560 561 return nm; 562 } 563 564 #endif // def HAVE_DTRACE_H 565 566 nmethod* nmethod::new_nmethod(methodHandle method, 567 int compile_id, 568 int entry_bci, 569 CodeOffsets* offsets, 570 int orig_pc_offset, 571 DebugInformationRecorder* debug_info, 572 Dependencies* dependencies, 573 CodeBuffer* code_buffer, int frame_size, 574 OopMapSet* oop_maps, 575 ExceptionHandlerTable* handler_table, 576 ImplicitExceptionTable* nul_chk_table, 577 AbstractCompiler* compiler, 578 int comp_level 579 ) 580 { 581 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 582 code_buffer->finalize_oop_references(method); 583 // create nmethod 584 nmethod* nm = NULL; 585 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 586 int nmethod_size = 587 allocation_size(code_buffer, sizeof(nmethod)) 588 + adjust_pcs_size(debug_info->pcs_size()) 589 + round_to(dependencies->size_in_bytes() , oopSize) 590 + round_to(handler_table->size_in_bytes(), oopSize) 591 + round_to(nul_chk_table->size_in_bytes(), oopSize) 592 + round_to(debug_info->data_size() , oopSize); 593 594 nm = new (nmethod_size) 595 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, 596 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, 597 oop_maps, 598 handler_table, 599 nul_chk_table, 600 compiler, 601 comp_level); 602 603 if (nm != NULL) { 604 // To make dependency checking during class loading fast, record 605 // the nmethod dependencies in the classes it is dependent on. 606 // This allows the dependency checking code to simply walk the 607 // class hierarchy above the loaded class, checking only nmethods 608 // which are dependent on those classes. The slow way is to 609 // check every nmethod for dependencies which makes it linear in 610 // the number of methods compiled. For applications with a lot 611 // classes the slow way is too slow. 612 for (Dependencies::DepStream deps(nm); deps.next(); ) { 613 Klass* klass = deps.context_type(); 614 if (klass == NULL) { 615 continue; // ignore things like evol_method 616 } 617 618 // record this nmethod as dependent on this klass 619 InstanceKlass::cast(klass)->add_dependent_nmethod(nm); 620 } 621 } 622 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); 623 if (PrintAssembly && nm != NULL) { 624 Disassembler::decode(nm); 625 } 626 } 627 628 // verify nmethod 629 debug_only(if (nm) nm->verify();) // might block 630 631 if (nm != NULL) { 632 nm->log_new_nmethod(); 633 } 634 635 // done 636 return nm; 637 } 638 639 640 // For native wrappers 641 nmethod::nmethod( 642 Method* method, 643 int nmethod_size, 644 int compile_id, 645 CodeOffsets* offsets, 646 CodeBuffer* code_buffer, 647 int frame_size, 648 ByteSize basic_lock_owner_sp_offset, 649 ByteSize basic_lock_sp_offset, 650 OopMapSet* oop_maps ) 651 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod), 652 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 653 _native_receiver_sp_offset(basic_lock_owner_sp_offset), 654 _native_basic_lock_sp_offset(basic_lock_sp_offset) 655 { 656 { 657 debug_only(No_Safepoint_Verifier nsv;) 658 assert_locked_or_safepoint(CodeCache_lock); 659 660 init_defaults(); 661 _method = method; 662 _entry_bci = InvocationEntryBci; 663 // We have no exception handler or deopt handler make the 664 // values something that will never match a pc like the nmethod vtable entry 665 _exception_offset = 0; 666 _deoptimize_offset = 0; 667 _deoptimize_mh_offset = 0; 668 _orig_pc_offset = 0; 669 670 _consts_offset = data_offset(); 671 _stub_offset = data_offset(); 672 _oops_offset = data_offset(); 673 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 674 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 675 _scopes_pcs_offset = _scopes_data_offset; 676 _dependencies_offset = _scopes_pcs_offset; 677 _handler_table_offset = _dependencies_offset; 678 _nul_chk_table_offset = _handler_table_offset; 679 _nmethod_end_offset = _nul_chk_table_offset; 680 _compile_id = compile_id; 681 _comp_level = CompLevel_none; 682 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 683 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 684 _osr_entry_point = NULL; 685 _exception_cache = NULL; 686 _pc_desc_cache.reset_to(NULL); 687 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 688 689 code_buffer->copy_values_to(this); 690 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 691 CodeCache::add_scavenge_root_nmethod(this); 692 Universe::heap()->register_nmethod(this); 693 } 694 debug_only(verify_scavenge_root_oops()); 695 CodeCache::commit(this); 696 } 697 698 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 699 ttyLocker ttyl; // keep the following output all in one block 700 // This output goes directly to the tty, not the compiler log. 701 // To enable tools to match it up with the compilation activity, 702 // be sure to tag this tty output with the compile ID. 703 if (xtty != NULL) { 704 xtty->begin_head("print_native_nmethod"); 705 xtty->method(_method); 706 xtty->stamp(); 707 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 708 } 709 // print the header part first 710 print(); 711 // then print the requested information 712 if (PrintNativeNMethods) { 713 print_code(); 714 if (oop_maps != NULL) { 715 oop_maps->print(); 716 } 717 } 718 if (PrintRelocations) { 719 print_relocations(); 720 } 721 if (xtty != NULL) { 722 xtty->tail("print_native_nmethod"); 723 } 724 } 725 } 726 727 // For dtrace wrappers 728 #ifdef HAVE_DTRACE_H 729 nmethod::nmethod( 730 Method* method, 731 int nmethod_size, 732 CodeOffsets* offsets, 733 CodeBuffer* code_buffer, 734 int frame_size) 735 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod), 736 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL), 737 _native_receiver_sp_offset(in_ByteSize(-1)), 738 _native_basic_lock_sp_offset(in_ByteSize(-1)) 739 { 740 { 741 debug_only(No_Safepoint_Verifier nsv;) 742 assert_locked_or_safepoint(CodeCache_lock); 743 744 init_defaults(); 745 _method = method; 746 _entry_bci = InvocationEntryBci; 747 // We have no exception handler or deopt handler make the 748 // values something that will never match a pc like the nmethod vtable entry 749 _exception_offset = 0; 750 _deoptimize_offset = 0; 751 _deoptimize_mh_offset = 0; 752 _unwind_handler_offset = -1; 753 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap); 754 _orig_pc_offset = 0; 755 _consts_offset = data_offset(); 756 _stub_offset = data_offset(); 757 _oops_offset = data_offset(); 758 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 759 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 760 _scopes_pcs_offset = _scopes_data_offset; 761 _dependencies_offset = _scopes_pcs_offset; 762 _handler_table_offset = _dependencies_offset; 763 _nul_chk_table_offset = _handler_table_offset; 764 _nmethod_end_offset = _nul_chk_table_offset; 765 _compile_id = 0; // default 766 _comp_level = CompLevel_none; 767 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 768 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 769 _osr_entry_point = NULL; 770 _exception_cache = NULL; 771 _pc_desc_cache.reset_to(NULL); 772 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 773 774 code_buffer->copy_values_to(this); 775 debug_only(verify_scavenge_root_oops()); 776 CodeCache::commit(this); 777 } 778 779 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 780 ttyLocker ttyl; // keep the following output all in one block 781 // This output goes directly to the tty, not the compiler log. 782 // To enable tools to match it up with the compilation activity, 783 // be sure to tag this tty output with the compile ID. 784 if (xtty != NULL) { 785 xtty->begin_head("print_dtrace_nmethod"); 786 xtty->method(_method); 787 xtty->stamp(); 788 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 789 } 790 // print the header part first 791 print(); 792 // then print the requested information 793 if (PrintNMethods) { 794 print_code(); 795 } 796 if (PrintRelocations) { 797 print_relocations(); 798 } 799 if (xtty != NULL) { 800 xtty->tail("print_dtrace_nmethod"); 801 } 802 } 803 } 804 #endif // def HAVE_DTRACE_H 805 806 void* nmethod::operator new(size_t size, int nmethod_size) throw() { 807 // Not critical, may return null if there is too little continuous memory 808 return CodeCache::allocate(nmethod_size); 809 } 810 811 nmethod::nmethod( 812 Method* method, 813 int nmethod_size, 814 int compile_id, 815 int entry_bci, 816 CodeOffsets* offsets, 817 int orig_pc_offset, 818 DebugInformationRecorder* debug_info, 819 Dependencies* dependencies, 820 CodeBuffer *code_buffer, 821 int frame_size, 822 OopMapSet* oop_maps, 823 ExceptionHandlerTable* handler_table, 824 ImplicitExceptionTable* nul_chk_table, 825 AbstractCompiler* compiler, 826 int comp_level 827 ) 828 : CodeBlob("nmethod", code_buffer, sizeof(nmethod), 829 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 830 _native_receiver_sp_offset(in_ByteSize(-1)), 831 _native_basic_lock_sp_offset(in_ByteSize(-1)) 832 { 833 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 834 { 835 debug_only(No_Safepoint_Verifier nsv;) 836 assert_locked_or_safepoint(CodeCache_lock); 837 838 init_defaults(); 839 _method = method; 840 _entry_bci = entry_bci; 841 _compile_id = compile_id; 842 _comp_level = comp_level; 843 _compiler = compiler; 844 _orig_pc_offset = orig_pc_offset; 845 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 846 847 // Section offsets 848 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts()); 849 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs()); 850 851 // Exception handler and deopt handler are in the stub section 852 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set"); 853 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set"); 854 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions); 855 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt); 856 if (offsets->value(CodeOffsets::DeoptMH) != -1) { 857 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH); 858 } else { 859 _deoptimize_mh_offset = -1; 860 } 861 if (offsets->value(CodeOffsets::UnwindHandler) != -1) { 862 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler); 863 } else { 864 _unwind_handler_offset = -1; 865 } 866 867 _oops_offset = data_offset(); 868 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 869 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 870 871 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize); 872 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size()); 873 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize); 874 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize); 875 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize); 876 877 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 878 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 879 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry); 880 _exception_cache = NULL; 881 _pc_desc_cache.reset_to(scopes_pcs_begin()); 882 883 // Copy contents of ScopeDescRecorder to nmethod 884 code_buffer->copy_values_to(this); 885 debug_info->copy_to(this); 886 dependencies->copy_to(this); 887 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 888 CodeCache::add_scavenge_root_nmethod(this); 889 Universe::heap()->register_nmethod(this); 890 } 891 debug_only(verify_scavenge_root_oops()); 892 893 CodeCache::commit(this); 894 895 // Copy contents of ExceptionHandlerTable to nmethod 896 handler_table->copy_to(this); 897 nul_chk_table->copy_to(this); 898 899 // we use the information of entry points to find out if a method is 900 // static or non static 901 assert(compiler->is_c2() || 902 _method->is_static() == (entry_point() == _verified_entry_point), 903 " entry points must be same for static methods and vice versa"); 904 } 905 906 bool printnmethods = PrintNMethods 907 || CompilerOracle::should_print(_method) 908 || CompilerOracle::has_option_string(_method, "PrintNMethods"); 909 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) { 910 print_nmethod(printnmethods); 911 } 912 } 913 914 915 // Print a short set of xml attributes to identify this nmethod. The 916 // output should be embedded in some other element. 917 void nmethod::log_identity(xmlStream* log) const { 918 log->print(" compile_id='%d'", compile_id()); 919 const char* nm_kind = compile_kind(); 920 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind); 921 if (compiler() != NULL) { 922 log->print(" compiler='%s'", compiler()->name()); 923 } 924 if (TieredCompilation) { 925 log->print(" level='%d'", comp_level()); 926 } 927 } 928 929 930 #define LOG_OFFSET(log, name) \ 931 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \ 932 log->print(" " XSTR(name) "_offset='%d'" , \ 933 (intptr_t)name##_begin() - (intptr_t)this) 934 935 936 void nmethod::log_new_nmethod() const { 937 if (LogCompilation && xtty != NULL) { 938 ttyLocker ttyl; 939 HandleMark hm; 940 xtty->begin_elem("nmethod"); 941 log_identity(xtty); 942 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size()); 943 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this); 944 945 LOG_OFFSET(xtty, relocation); 946 LOG_OFFSET(xtty, consts); 947 LOG_OFFSET(xtty, insts); 948 LOG_OFFSET(xtty, stub); 949 LOG_OFFSET(xtty, scopes_data); 950 LOG_OFFSET(xtty, scopes_pcs); 951 LOG_OFFSET(xtty, dependencies); 952 LOG_OFFSET(xtty, handler_table); 953 LOG_OFFSET(xtty, nul_chk_table); 954 LOG_OFFSET(xtty, oops); 955 956 xtty->method(method()); 957 xtty->stamp(); 958 xtty->end_elem(); 959 } 960 } 961 962 #undef LOG_OFFSET 963 964 965 // Print out more verbose output usually for a newly created nmethod. 966 void nmethod::print_on(outputStream* st, const char* msg) const { 967 if (st != NULL) { 968 ttyLocker ttyl; 969 if (WizardMode) { 970 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true); 971 st->print_cr(" (" INTPTR_FORMAT ")", this); 972 } else { 973 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false); 974 } 975 } 976 } 977 978 979 void nmethod::print_nmethod(bool printmethod) { 980 ttyLocker ttyl; // keep the following output all in one block 981 if (xtty != NULL) { 982 xtty->begin_head("print_nmethod"); 983 xtty->stamp(); 984 xtty->end_head(); 985 } 986 // print the header part first 987 print(); 988 // then print the requested information 989 if (printmethod) { 990 print_code(); 991 print_pcs(); 992 if (oop_maps()) { 993 oop_maps()->print(); 994 } 995 } 996 if (PrintDebugInfo) { 997 print_scopes(); 998 } 999 if (PrintRelocations) { 1000 print_relocations(); 1001 } 1002 if (PrintDependencies) { 1003 print_dependencies(); 1004 } 1005 if (PrintExceptionHandlers) { 1006 print_handler_table(); 1007 print_nul_chk_table(); 1008 } 1009 if (xtty != NULL) { 1010 xtty->tail("print_nmethod"); 1011 } 1012 } 1013 1014 1015 // Promote one word from an assembly-time handle to a live embedded oop. 1016 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) { 1017 if (handle == NULL || 1018 // As a special case, IC oops are initialized to 1 or -1. 1019 handle == (jobject) Universe::non_oop_word()) { 1020 (*dest) = (oop) handle; 1021 } else { 1022 (*dest) = JNIHandles::resolve_non_null(handle); 1023 } 1024 } 1025 1026 1027 // Have to have the same name because it's called by a template 1028 void nmethod::copy_values(GrowableArray<jobject>* array) { 1029 int length = array->length(); 1030 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough"); 1031 oop* dest = oops_begin(); 1032 for (int index = 0 ; index < length; index++) { 1033 initialize_immediate_oop(&dest[index], array->at(index)); 1034 } 1035 1036 // Now we can fix up all the oops in the code. We need to do this 1037 // in the code because the assembler uses jobjects as placeholders. 1038 // The code and relocations have already been initialized by the 1039 // CodeBlob constructor, so it is valid even at this early point to 1040 // iterate over relocations and patch the code. 1041 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true); 1042 } 1043 1044 void nmethod::copy_values(GrowableArray<Metadata*>* array) { 1045 int length = array->length(); 1046 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough"); 1047 Metadata** dest = metadata_begin(); 1048 for (int index = 0 ; index < length; index++) { 1049 dest[index] = array->at(index); 1050 } 1051 } 1052 1053 bool nmethod::is_at_poll_return(address pc) { 1054 RelocIterator iter(this, pc, pc+1); 1055 while (iter.next()) { 1056 if (iter.type() == relocInfo::poll_return_type) 1057 return true; 1058 } 1059 return false; 1060 } 1061 1062 1063 bool nmethod::is_at_poll_or_poll_return(address pc) { 1064 RelocIterator iter(this, pc, pc+1); 1065 while (iter.next()) { 1066 relocInfo::relocType t = iter.type(); 1067 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type) 1068 return true; 1069 } 1070 return false; 1071 } 1072 1073 1074 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) { 1075 // re-patch all oop-bearing instructions, just in case some oops moved 1076 RelocIterator iter(this, begin, end); 1077 while (iter.next()) { 1078 if (iter.type() == relocInfo::oop_type) { 1079 oop_Relocation* reloc = iter.oop_reloc(); 1080 if (initialize_immediates && reloc->oop_is_immediate()) { 1081 oop* dest = reloc->oop_addr(); 1082 initialize_immediate_oop(dest, (jobject) *dest); 1083 } 1084 // Refresh the oop-related bits of this instruction. 1085 reloc->fix_oop_relocation(); 1086 } else if (iter.type() == relocInfo::metadata_type) { 1087 metadata_Relocation* reloc = iter.metadata_reloc(); 1088 reloc->fix_metadata_relocation(); 1089 } 1090 } 1091 } 1092 1093 1094 void nmethod::verify_oop_relocations() { 1095 // Ensure sure that the code matches the current oop values 1096 RelocIterator iter(this, NULL, NULL); 1097 while (iter.next()) { 1098 if (iter.type() == relocInfo::oop_type) { 1099 oop_Relocation* reloc = iter.oop_reloc(); 1100 if (!reloc->oop_is_immediate()) { 1101 reloc->verify_oop_relocation(); 1102 } 1103 } 1104 } 1105 } 1106 1107 1108 ScopeDesc* nmethod::scope_desc_at(address pc) { 1109 PcDesc* pd = pc_desc_at(pc); 1110 guarantee(pd != NULL, "scope must be present"); 1111 return new ScopeDesc(this, pd->scope_decode_offset(), 1112 pd->obj_decode_offset(), pd->should_reexecute(), 1113 pd->return_oop()); 1114 } 1115 1116 1117 void nmethod::clear_inline_caches() { 1118 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint"); 1119 if (is_zombie()) { 1120 return; 1121 } 1122 1123 RelocIterator iter(this); 1124 while (iter.next()) { 1125 iter.reloc()->clear_inline_cache(); 1126 } 1127 } 1128 1129 1130 void nmethod::cleanup_inline_caches() { 1131 1132 assert_locked_or_safepoint(CompiledIC_lock); 1133 1134 // If the method is not entrant or zombie then a JMP is plastered over the 1135 // first few bytes. If an oop in the old code was there, that oop 1136 // should not get GC'd. Skip the first few bytes of oops on 1137 // not-entrant methods. 1138 address low_boundary = verified_entry_point(); 1139 if (!is_in_use()) { 1140 low_boundary += NativeJump::instruction_size; 1141 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1142 // This means that the low_boundary is going to be a little too high. 1143 // This shouldn't matter, since oops of non-entrant methods are never used. 1144 // In fact, why are we bothering to look at oops in a non-entrant method?? 1145 } 1146 1147 // Find all calls in an nmethod, and clear the ones that points to zombie methods 1148 ResourceMark rm; 1149 RelocIterator iter(this, low_boundary); 1150 while(iter.next()) { 1151 switch(iter.type()) { 1152 case relocInfo::virtual_call_type: 1153 case relocInfo::opt_virtual_call_type: { 1154 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1155 // Ok, to lookup references to zombies here 1156 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1157 if( cb != NULL && cb->is_nmethod() ) { 1158 nmethod* nm = (nmethod*)cb; 1159 // Clean inline caches pointing to both zombie and not_entrant methods 1160 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(); 1161 } 1162 break; 1163 } 1164 case relocInfo::static_call_type: { 1165 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1166 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1167 if( cb != NULL && cb->is_nmethod() ) { 1168 nmethod* nm = (nmethod*)cb; 1169 // Clean inline caches pointing to both zombie and not_entrant methods 1170 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean(); 1171 } 1172 break; 1173 } 1174 } 1175 } 1176 } 1177 1178 // This is a private interface with the sweeper. 1179 void nmethod::mark_as_seen_on_stack() { 1180 assert(is_alive(), "Must be an alive method"); 1181 // Set the traversal mark to ensure that the sweeper does 2 1182 // cleaning passes before moving to zombie. 1183 set_stack_traversal_mark(NMethodSweeper::traversal_count()); 1184 } 1185 1186 // Tell if a non-entrant method can be converted to a zombie (i.e., 1187 // there are no activations on the stack, not in use by the VM, 1188 // and not in use by the ServiceThread) 1189 bool nmethod::can_not_entrant_be_converted() { 1190 assert(is_not_entrant(), "must be a non-entrant method"); 1191 1192 // Since the nmethod sweeper only does partial sweep the sweeper's traversal 1193 // count can be greater than the stack traversal count before it hits the 1194 // nmethod for the second time. 1195 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() && 1196 !is_locked_by_vm(); 1197 } 1198 1199 void nmethod::inc_decompile_count() { 1200 if (!is_compiled_by_c2()) return; 1201 // Could be gated by ProfileTraps, but do not bother... 1202 Method* m = method(); 1203 if (m == NULL) return; 1204 MethodData* mdo = m->method_data(); 1205 if (mdo == NULL) return; 1206 // There is a benign race here. See comments in methodData.hpp. 1207 mdo->inc_decompile_count(); 1208 } 1209 1210 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) { 1211 1212 post_compiled_method_unload(); 1213 1214 // Since this nmethod is being unloaded, make sure that dependencies 1215 // recorded in instanceKlasses get flushed and pass non-NULL closure to 1216 // indicate that this work is being done during a GC. 1217 assert(Universe::heap()->is_gc_active(), "should only be called during gc"); 1218 assert(is_alive != NULL, "Should be non-NULL"); 1219 // A non-NULL is_alive closure indicates that this is being called during GC. 1220 flush_dependencies(is_alive); 1221 1222 // Break cycle between nmethod & method 1223 if (TraceClassUnloading && WizardMode) { 1224 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT 1225 " unloadable], Method*(" INTPTR_FORMAT 1226 "), cause(" INTPTR_FORMAT ")", 1227 this, (address)_method, (address)cause); 1228 if (!Universe::heap()->is_gc_active()) 1229 cause->klass()->print(); 1230 } 1231 // Unlink the osr method, so we do not look this up again 1232 if (is_osr_method()) { 1233 invalidate_osr_method(); 1234 } 1235 // If _method is already NULL the Method* is about to be unloaded, 1236 // so we don't have to break the cycle. Note that it is possible to 1237 // have the Method* live here, in case we unload the nmethod because 1238 // it is pointing to some oop (other than the Method*) being unloaded. 1239 if (_method != NULL) { 1240 // OSR methods point to the Method*, but the Method* does not 1241 // point back! 1242 if (_method->code() == this) { 1243 _method->clear_code(); // Break a cycle 1244 } 1245 _method = NULL; // Clear the method of this dead nmethod 1246 } 1247 // Make the class unloaded - i.e., change state and notify sweeper 1248 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1249 if (is_in_use()) { 1250 // Transitioning directly from live to unloaded -- so 1251 // we need to force a cache clean-up; remember this 1252 // for later on. 1253 CodeCache::set_needs_cache_clean(true); 1254 } 1255 _state = unloaded; 1256 1257 // Log the unloading. 1258 log_state_change(); 1259 1260 // The Method* is gone at this point 1261 assert(_method == NULL, "Tautology"); 1262 1263 set_osr_link(NULL); 1264 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods 1265 NMethodSweeper::report_state_change(this); 1266 } 1267 1268 void nmethod::invalidate_osr_method() { 1269 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); 1270 // Remove from list of active nmethods 1271 if (method() != NULL) 1272 method()->method_holder()->remove_osr_nmethod(this); 1273 // Set entry as invalid 1274 _entry_bci = InvalidOSREntryBci; 1275 } 1276 1277 void nmethod::log_state_change() const { 1278 if (LogCompilation) { 1279 if (xtty != NULL) { 1280 ttyLocker ttyl; // keep the following output all in one block 1281 if (_state == unloaded) { 1282 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'", 1283 os::current_thread_id()); 1284 } else { 1285 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s", 1286 os::current_thread_id(), 1287 (_state == zombie ? " zombie='1'" : "")); 1288 } 1289 log_identity(xtty); 1290 xtty->stamp(); 1291 xtty->end_elem(); 1292 } 1293 } 1294 if (PrintCompilation && _state != unloaded) { 1295 print_on(tty, _state == zombie ? "made zombie" : "made not entrant"); 1296 } 1297 } 1298 1299 /** 1300 * Common functionality for both make_not_entrant and make_zombie 1301 */ 1302 bool nmethod::make_not_entrant_or_zombie(unsigned int state) { 1303 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant"); 1304 assert(!is_zombie(), "should not already be a zombie"); 1305 1306 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below. 1307 nmethodLocker nml(this); 1308 methodHandle the_method(method()); 1309 No_Safepoint_Verifier nsv; 1310 1311 // during patching, depending on the nmethod state we must notify the GC that 1312 // code has been unloaded, unregistering it. We cannot do this right while 1313 // holding the Patching_lock because we need to use the CodeCache_lock. This 1314 // would be prone to deadlocks. 1315 // This flag is used to remember whether we need to later lock and unregister. 1316 bool nmethod_needs_unregister = false; 1317 1318 { 1319 // invalidate osr nmethod before acquiring the patching lock since 1320 // they both acquire leaf locks and we don't want a deadlock. 1321 // This logic is equivalent to the logic below for patching the 1322 // verified entry point of regular methods. 1323 if (is_osr_method()) { 1324 // this effectively makes the osr nmethod not entrant 1325 invalidate_osr_method(); 1326 } 1327 1328 // Enter critical section. Does not block for safepoint. 1329 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1330 1331 if (_state == state) { 1332 // another thread already performed this transition so nothing 1333 // to do, but return false to indicate this. 1334 return false; 1335 } 1336 1337 // The caller can be calling the method statically or through an inline 1338 // cache call. 1339 if (!is_osr_method() && !is_not_entrant()) { 1340 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(), 1341 SharedRuntime::get_handle_wrong_method_stub()); 1342 } 1343 1344 if (is_in_use()) { 1345 // It's a true state change, so mark the method as decompiled. 1346 // Do it only for transition from alive. 1347 inc_decompile_count(); 1348 } 1349 1350 // If the state is becoming a zombie, signal to unregister the nmethod with 1351 // the heap. 1352 // This nmethod may have already been unloaded during a full GC. 1353 if ((state == zombie) && !is_unloaded()) { 1354 nmethod_needs_unregister = true; 1355 } 1356 1357 // Must happen before state change. Otherwise we have a race condition in 1358 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately 1359 // transition its state from 'not_entrant' to 'zombie' without having to wait 1360 // for stack scanning. 1361 if (state == not_entrant) { 1362 mark_as_seen_on_stack(); 1363 OrderAccess::storestore(); 1364 } 1365 1366 // Change state 1367 _state = state; 1368 1369 // Log the transition once 1370 log_state_change(); 1371 1372 // Remove nmethod from method. 1373 // We need to check if both the _code and _from_compiled_code_entry_point 1374 // refer to this nmethod because there is a race in setting these two fields 1375 // in Method* as seen in bugid 4947125. 1376 // If the vep() points to the zombie nmethod, the memory for the nmethod 1377 // could be flushed and the compiler and vtable stubs could still call 1378 // through it. 1379 if (method() != NULL && (method()->code() == this || 1380 method()->from_compiled_entry() == verified_entry_point())) { 1381 HandleMark hm; 1382 method()->clear_code(); 1383 } 1384 } // leave critical region under Patching_lock 1385 1386 // When the nmethod becomes zombie it is no longer alive so the 1387 // dependencies must be flushed. nmethods in the not_entrant 1388 // state will be flushed later when the transition to zombie 1389 // happens or they get unloaded. 1390 if (state == zombie) { 1391 { 1392 // Flushing dependecies must be done before any possible 1393 // safepoint can sneak in, otherwise the oops used by the 1394 // dependency logic could have become stale. 1395 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1396 if (nmethod_needs_unregister) { 1397 Universe::heap()->unregister_nmethod(this); 1398 } 1399 flush_dependencies(NULL); 1400 } 1401 1402 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload 1403 // event and it hasn't already been reported for this nmethod then 1404 // report it now. The event may have been reported earilier if the GC 1405 // marked it for unloading). JvmtiDeferredEventQueue support means 1406 // we no longer go to a safepoint here. 1407 post_compiled_method_unload(); 1408 1409 #ifdef ASSERT 1410 // It's no longer safe to access the oops section since zombie 1411 // nmethods aren't scanned for GC. 1412 _oops_are_stale = true; 1413 #endif 1414 // the Method may be reclaimed by class unloading now that the 1415 // nmethod is in zombie state 1416 set_method(NULL); 1417 } else { 1418 assert(state == not_entrant, "other cases may need to be handled differently"); 1419 } 1420 1421 if (TraceCreateZombies) { 1422 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie"); 1423 } 1424 1425 NMethodSweeper::report_state_change(this); 1426 return true; 1427 } 1428 1429 void nmethod::flush() { 1430 // Note that there are no valid oops in the nmethod anymore. 1431 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method"); 1432 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation"); 1433 1434 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed"); 1435 assert_locked_or_safepoint(CodeCache_lock); 1436 1437 // completely deallocate this method 1438 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this); 1439 if (PrintMethodFlushing) { 1440 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb", 1441 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024); 1442 } 1443 1444 // We need to deallocate any ExceptionCache data. 1445 // Note that we do not need to grab the nmethod lock for this, it 1446 // better be thread safe if we're disposing of it! 1447 ExceptionCache* ec = exception_cache(); 1448 set_exception_cache(NULL); 1449 while(ec != NULL) { 1450 ExceptionCache* next = ec->next(); 1451 delete ec; 1452 ec = next; 1453 } 1454 1455 if (on_scavenge_root_list()) { 1456 CodeCache::drop_scavenge_root_nmethod(this); 1457 } 1458 1459 #ifdef SHARK 1460 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin()); 1461 #endif // SHARK 1462 1463 ((CodeBlob*)(this))->flush(); 1464 1465 CodeCache::free(this); 1466 } 1467 1468 1469 // 1470 // Notify all classes this nmethod is dependent on that it is no 1471 // longer dependent. This should only be called in two situations. 1472 // First, when a nmethod transitions to a zombie all dependents need 1473 // to be clear. Since zombification happens at a safepoint there's no 1474 // synchronization issues. The second place is a little more tricky. 1475 // During phase 1 of mark sweep class unloading may happen and as a 1476 // result some nmethods may get unloaded. In this case the flushing 1477 // of dependencies must happen during phase 1 since after GC any 1478 // dependencies in the unloaded nmethod won't be updated, so 1479 // traversing the dependency information in unsafe. In that case this 1480 // function is called with a non-NULL argument and this function only 1481 // notifies instanceKlasses that are reachable 1482 1483 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) { 1484 assert_locked_or_safepoint(CodeCache_lock); 1485 assert(Universe::heap()->is_gc_active() == (is_alive != NULL), 1486 "is_alive is non-NULL if and only if we are called during GC"); 1487 if (!has_flushed_dependencies()) { 1488 set_has_flushed_dependencies(); 1489 for (Dependencies::DepStream deps(this); deps.next(); ) { 1490 Klass* klass = deps.context_type(); 1491 if (klass == NULL) continue; // ignore things like evol_method 1492 1493 // During GC the is_alive closure is non-NULL, and is used to 1494 // determine liveness of dependees that need to be updated. 1495 if (is_alive == NULL || klass->is_loader_alive(is_alive)) { 1496 InstanceKlass::cast(klass)->remove_dependent_nmethod(this); 1497 } 1498 } 1499 } 1500 } 1501 1502 1503 // If this oop is not live, the nmethod can be unloaded. 1504 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) { 1505 assert(root != NULL, "just checking"); 1506 oop obj = *root; 1507 if (obj == NULL || is_alive->do_object_b(obj)) { 1508 return false; 1509 } 1510 1511 // If ScavengeRootsInCode is true, an nmethod might be unloaded 1512 // simply because one of its constant oops has gone dead. 1513 // No actual classes need to be unloaded in order for this to occur. 1514 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading"); 1515 make_unloaded(is_alive, obj); 1516 return true; 1517 } 1518 1519 // ------------------------------------------------------------------ 1520 // post_compiled_method_load_event 1521 // new method for install_code() path 1522 // Transfer information from compilation to jvmti 1523 void nmethod::post_compiled_method_load_event() { 1524 1525 Method* moop = method(); 1526 #ifndef USDT2 1527 HS_DTRACE_PROBE8(hotspot, compiled__method__load, 1528 moop->klass_name()->bytes(), 1529 moop->klass_name()->utf8_length(), 1530 moop->name()->bytes(), 1531 moop->name()->utf8_length(), 1532 moop->signature()->bytes(), 1533 moop->signature()->utf8_length(), 1534 insts_begin(), insts_size()); 1535 #else /* USDT2 */ 1536 HOTSPOT_COMPILED_METHOD_LOAD( 1537 (char *) moop->klass_name()->bytes(), 1538 moop->klass_name()->utf8_length(), 1539 (char *) moop->name()->bytes(), 1540 moop->name()->utf8_length(), 1541 (char *) moop->signature()->bytes(), 1542 moop->signature()->utf8_length(), 1543 insts_begin(), insts_size()); 1544 #endif /* USDT2 */ 1545 1546 if (JvmtiExport::should_post_compiled_method_load() || 1547 JvmtiExport::should_post_compiled_method_unload()) { 1548 get_and_cache_jmethod_id(); 1549 } 1550 1551 if (JvmtiExport::should_post_compiled_method_load()) { 1552 // Let the Service thread (which is a real Java thread) post the event 1553 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1554 JvmtiDeferredEventQueue::enqueue( 1555 JvmtiDeferredEvent::compiled_method_load_event(this)); 1556 } 1557 } 1558 1559 jmethodID nmethod::get_and_cache_jmethod_id() { 1560 if (_jmethod_id == NULL) { 1561 // Cache the jmethod_id since it can no longer be looked up once the 1562 // method itself has been marked for unloading. 1563 _jmethod_id = method()->jmethod_id(); 1564 } 1565 return _jmethod_id; 1566 } 1567 1568 void nmethod::post_compiled_method_unload() { 1569 if (unload_reported()) { 1570 // During unloading we transition to unloaded and then to zombie 1571 // and the unloading is reported during the first transition. 1572 return; 1573 } 1574 1575 assert(_method != NULL && !is_unloaded(), "just checking"); 1576 DTRACE_METHOD_UNLOAD_PROBE(method()); 1577 1578 // If a JVMTI agent has enabled the CompiledMethodUnload event then 1579 // post the event. Sometime later this nmethod will be made a zombie 1580 // by the sweeper but the Method* will not be valid at that point. 1581 // If the _jmethod_id is null then no load event was ever requested 1582 // so don't bother posting the unload. The main reason for this is 1583 // that the jmethodID is a weak reference to the Method* so if 1584 // it's being unloaded there's no way to look it up since the weak 1585 // ref will have been cleared. 1586 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) { 1587 assert(!unload_reported(), "already unloaded"); 1588 JvmtiDeferredEvent event = 1589 JvmtiDeferredEvent::compiled_method_unload_event(this, 1590 _jmethod_id, insts_begin()); 1591 if (SafepointSynchronize::is_at_safepoint()) { 1592 // Don't want to take the queueing lock. Add it as pending and 1593 // it will get enqueued later. 1594 JvmtiDeferredEventQueue::add_pending_event(event); 1595 } else { 1596 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1597 JvmtiDeferredEventQueue::enqueue(event); 1598 } 1599 } 1600 1601 // The JVMTI CompiledMethodUnload event can be enabled or disabled at 1602 // any time. As the nmethod is being unloaded now we mark it has 1603 // having the unload event reported - this will ensure that we don't 1604 // attempt to report the event in the unlikely scenario where the 1605 // event is enabled at the time the nmethod is made a zombie. 1606 set_unload_reported(); 1607 } 1608 1609 // This is called at the end of the strong tracing/marking phase of a 1610 // GC to unload an nmethod if it contains otherwise unreachable 1611 // oops. 1612 1613 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) { 1614 // Make sure the oop's ready to receive visitors 1615 assert(!is_zombie() && !is_unloaded(), 1616 "should not call follow on zombie or unloaded nmethod"); 1617 1618 // If the method is not entrant then a JMP is plastered over the 1619 // first few bytes. If an oop in the old code was there, that oop 1620 // should not get GC'd. Skip the first few bytes of oops on 1621 // not-entrant methods. 1622 address low_boundary = verified_entry_point(); 1623 if (is_not_entrant()) { 1624 low_boundary += NativeJump::instruction_size; 1625 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1626 // (See comment above.) 1627 } 1628 1629 // The RedefineClasses() API can cause the class unloading invariant 1630 // to no longer be true. See jvmtiExport.hpp for details. 1631 // Also, leave a debugging breadcrumb in local flag. 1632 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class(); 1633 if (a_class_was_redefined) { 1634 // This set of the unloading_occurred flag is done before the 1635 // call to post_compiled_method_unload() so that the unloading 1636 // of this nmethod is reported. 1637 unloading_occurred = true; 1638 } 1639 1640 // Exception cache 1641 ExceptionCache* ec = exception_cache(); 1642 while (ec != NULL) { 1643 Klass* ex_klass = ec->exception_type(); 1644 ExceptionCache* next_ec = ec->next(); 1645 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) { 1646 remove_from_exception_cache(ec); 1647 } 1648 ec = next_ec; 1649 } 1650 1651 // If class unloading occurred we first iterate over all inline caches and 1652 // clear ICs where the cached oop is referring to an unloaded klass or method. 1653 // The remaining live cached oops will be traversed in the relocInfo::oop_type 1654 // iteration below. 1655 if (unloading_occurred) { 1656 RelocIterator iter(this, low_boundary); 1657 while(iter.next()) { 1658 if (iter.type() == relocInfo::virtual_call_type) { 1659 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1660 if (ic->is_icholder_call()) { 1661 // The only exception is compiledICHolder oops which may 1662 // yet be marked below. (We check this further below). 1663 CompiledICHolder* cichk_oop = ic->cached_icholder(); 1664 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) && 1665 cichk_oop->holder_klass()->is_loader_alive(is_alive)) { 1666 continue; 1667 } 1668 } else { 1669 Metadata* ic_oop = ic->cached_metadata(); 1670 if (ic_oop != NULL) { 1671 if (ic_oop->is_klass()) { 1672 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) { 1673 continue; 1674 } 1675 } else if (ic_oop->is_method()) { 1676 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) { 1677 continue; 1678 } 1679 } else { 1680 ShouldNotReachHere(); 1681 } 1682 } 1683 } 1684 ic->set_to_clean(); 1685 } 1686 } 1687 } 1688 1689 // Compiled code 1690 { 1691 RelocIterator iter(this, low_boundary); 1692 while (iter.next()) { 1693 if (iter.type() == relocInfo::oop_type) { 1694 oop_Relocation* r = iter.oop_reloc(); 1695 // In this loop, we must only traverse those oops directly embedded in 1696 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1697 assert(1 == (r->oop_is_immediate()) + 1698 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1699 "oop must be found in exactly one place"); 1700 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1701 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) { 1702 return; 1703 } 1704 } 1705 } 1706 } 1707 } 1708 1709 1710 // Scopes 1711 for (oop* p = oops_begin(); p < oops_end(); p++) { 1712 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1713 if (can_unload(is_alive, p, unloading_occurred)) { 1714 return; 1715 } 1716 } 1717 1718 // Ensure that all metadata is still alive 1719 verify_metadata_loaders(low_boundary, is_alive); 1720 } 1721 1722 #ifdef ASSERT 1723 1724 class CheckClass : AllStatic { 1725 static BoolObjectClosure* _is_alive; 1726 1727 // Check class_loader is alive for this bit of metadata. 1728 static void check_class(Metadata* md) { 1729 Klass* klass = NULL; 1730 if (md->is_klass()) { 1731 klass = ((Klass*)md); 1732 } else if (md->is_method()) { 1733 klass = ((Method*)md)->method_holder(); 1734 } else if (md->is_methodData()) { 1735 klass = ((MethodData*)md)->method()->method_holder(); 1736 } else { 1737 md->print(); 1738 ShouldNotReachHere(); 1739 } 1740 assert(klass->is_loader_alive(_is_alive), "must be alive"); 1741 } 1742 public: 1743 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) { 1744 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint"); 1745 _is_alive = is_alive; 1746 nm->metadata_do(check_class); 1747 } 1748 }; 1749 1750 // This is called during a safepoint so can use static data 1751 BoolObjectClosure* CheckClass::_is_alive = NULL; 1752 #endif // ASSERT 1753 1754 1755 // Processing of oop references should have been sufficient to keep 1756 // all strong references alive. Any weak references should have been 1757 // cleared as well. Visit all the metadata and ensure that it's 1758 // really alive. 1759 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) { 1760 #ifdef ASSERT 1761 RelocIterator iter(this, low_boundary); 1762 while (iter.next()) { 1763 // static_stub_Relocations may have dangling references to 1764 // Method*s so trim them out here. Otherwise it looks like 1765 // compiled code is maintaining a link to dead metadata. 1766 address static_call_addr = NULL; 1767 if (iter.type() == relocInfo::opt_virtual_call_type) { 1768 CompiledIC* cic = CompiledIC_at(iter.reloc()); 1769 if (!cic->is_call_to_interpreted()) { 1770 static_call_addr = iter.addr(); 1771 } 1772 } else if (iter.type() == relocInfo::static_call_type) { 1773 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc()); 1774 if (!csc->is_call_to_interpreted()) { 1775 static_call_addr = iter.addr(); 1776 } 1777 } 1778 if (static_call_addr != NULL) { 1779 RelocIterator sciter(this, low_boundary); 1780 while (sciter.next()) { 1781 if (sciter.type() == relocInfo::static_stub_type && 1782 sciter.static_stub_reloc()->static_call() == static_call_addr) { 1783 sciter.static_stub_reloc()->clear_inline_cache(); 1784 } 1785 } 1786 } 1787 } 1788 // Check that the metadata embedded in the nmethod is alive 1789 CheckClass::do_check_class(is_alive, this); 1790 #endif 1791 } 1792 1793 1794 // Iterate over metadata calling this function. Used by RedefineClasses 1795 void nmethod::metadata_do(void f(Metadata*)) { 1796 address low_boundary = verified_entry_point(); 1797 if (is_not_entrant()) { 1798 low_boundary += NativeJump::instruction_size; 1799 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1800 // (See comment above.) 1801 } 1802 { 1803 // Visit all immediate references that are embedded in the instruction stream. 1804 RelocIterator iter(this, low_boundary); 1805 while (iter.next()) { 1806 if (iter.type() == relocInfo::metadata_type ) { 1807 metadata_Relocation* r = iter.metadata_reloc(); 1808 // In this lmetadata, we must only follow those metadatas directly embedded in 1809 // the code. Other metadatas (oop_index>0) are seen as part of 1810 // the metadata section below. 1811 assert(1 == (r->metadata_is_immediate()) + 1812 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), 1813 "metadata must be found in exactly one place"); 1814 if (r->metadata_is_immediate() && r->metadata_value() != NULL) { 1815 Metadata* md = r->metadata_value(); 1816 f(md); 1817 } 1818 } else if (iter.type() == relocInfo::virtual_call_type) { 1819 // Check compiledIC holders associated with this nmethod 1820 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1821 if (ic->is_icholder_call()) { 1822 CompiledICHolder* cichk = ic->cached_icholder(); 1823 f(cichk->holder_method()); 1824 f(cichk->holder_klass()); 1825 } else { 1826 Metadata* ic_oop = ic->cached_metadata(); 1827 if (ic_oop != NULL) { 1828 f(ic_oop); 1829 } 1830 } 1831 } 1832 } 1833 } 1834 1835 // Visit the metadata section 1836 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { 1837 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops 1838 Metadata* md = *p; 1839 f(md); 1840 } 1841 1842 // Call function Method*, not embedded in these other places. 1843 if (_method != NULL) f(_method); 1844 } 1845 1846 void nmethod::oops_do(OopClosure* f, bool allow_zombie) { 1847 // make sure the oops ready to receive visitors 1848 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod"); 1849 assert(!is_unloaded(), "should not call follow on unloaded nmethod"); 1850 1851 // If the method is not entrant or zombie then a JMP is plastered over the 1852 // first few bytes. If an oop in the old code was there, that oop 1853 // should not get GC'd. Skip the first few bytes of oops on 1854 // not-entrant methods. 1855 address low_boundary = verified_entry_point(); 1856 if (is_not_entrant()) { 1857 low_boundary += NativeJump::instruction_size; 1858 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1859 // (See comment above.) 1860 } 1861 1862 RelocIterator iter(this, low_boundary); 1863 1864 while (iter.next()) { 1865 if (iter.type() == relocInfo::oop_type ) { 1866 oop_Relocation* r = iter.oop_reloc(); 1867 // In this loop, we must only follow those oops directly embedded in 1868 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1869 assert(1 == (r->oop_is_immediate()) + 1870 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1871 "oop must be found in exactly one place"); 1872 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1873 f->do_oop(r->oop_addr()); 1874 } 1875 } 1876 } 1877 1878 // Scopes 1879 // This includes oop constants not inlined in the code stream. 1880 for (oop* p = oops_begin(); p < oops_end(); p++) { 1881 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1882 f->do_oop(p); 1883 } 1884 } 1885 1886 #define NMETHOD_SENTINEL ((nmethod*)badAddress) 1887 1888 nmethod* volatile nmethod::_oops_do_mark_nmethods; 1889 1890 // An nmethod is "marked" if its _mark_link is set non-null. 1891 // Even if it is the end of the linked list, it will have a non-null link value, 1892 // as long as it is on the list. 1893 // This code must be MP safe, because it is used from parallel GC passes. 1894 bool nmethod::test_set_oops_do_mark() { 1895 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called"); 1896 nmethod* observed_mark_link = _oops_do_mark_link; 1897 if (observed_mark_link == NULL) { 1898 // Claim this nmethod for this thread to mark. 1899 observed_mark_link = (nmethod*) 1900 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL); 1901 if (observed_mark_link == NULL) { 1902 1903 // Atomically append this nmethod (now claimed) to the head of the list: 1904 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods; 1905 for (;;) { 1906 nmethod* required_mark_nmethods = observed_mark_nmethods; 1907 _oops_do_mark_link = required_mark_nmethods; 1908 observed_mark_nmethods = (nmethod*) 1909 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods); 1910 if (observed_mark_nmethods == required_mark_nmethods) 1911 break; 1912 } 1913 // Mark was clear when we first saw this guy. 1914 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark")); 1915 return false; 1916 } 1917 } 1918 // On fall through, another racing thread marked this nmethod before we did. 1919 return true; 1920 } 1921 1922 void nmethod::oops_do_marking_prologue() { 1923 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue")); 1924 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row"); 1925 // We use cmpxchg_ptr instead of regular assignment here because the user 1926 // may fork a bunch of threads, and we need them all to see the same state. 1927 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL); 1928 guarantee(observed == NULL, "no races in this sequential code"); 1929 } 1930 1931 void nmethod::oops_do_marking_epilogue() { 1932 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row"); 1933 nmethod* cur = _oops_do_mark_nmethods; 1934 while (cur != NMETHOD_SENTINEL) { 1935 assert(cur != NULL, "not NULL-terminated"); 1936 nmethod* next = cur->_oops_do_mark_link; 1937 cur->_oops_do_mark_link = NULL; 1938 cur->fix_oop_relocations(); 1939 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark")); 1940 cur = next; 1941 } 1942 void* required = _oops_do_mark_nmethods; 1943 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required); 1944 guarantee(observed == required, "no races in this sequential code"); 1945 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]")); 1946 } 1947 1948 class DetectScavengeRoot: public OopClosure { 1949 bool _detected_scavenge_root; 1950 public: 1951 DetectScavengeRoot() : _detected_scavenge_root(false) 1952 { NOT_PRODUCT(_print_nm = NULL); } 1953 bool detected_scavenge_root() { return _detected_scavenge_root; } 1954 virtual void do_oop(oop* p) { 1955 if ((*p) != NULL && (*p)->is_scavengable()) { 1956 NOT_PRODUCT(maybe_print(p)); 1957 _detected_scavenge_root = true; 1958 } 1959 } 1960 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 1961 1962 #ifndef PRODUCT 1963 nmethod* _print_nm; 1964 void maybe_print(oop* p) { 1965 if (_print_nm == NULL) return; 1966 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root"); 1967 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")", 1968 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm), 1969 (void *)(*p), (intptr_t)p); 1970 (*p)->print(); 1971 } 1972 #endif //PRODUCT 1973 }; 1974 1975 bool nmethod::detect_scavenge_root_oops() { 1976 DetectScavengeRoot detect_scavenge_root; 1977 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this); 1978 oops_do(&detect_scavenge_root); 1979 return detect_scavenge_root.detected_scavenge_root(); 1980 } 1981 1982 // Method that knows how to preserve outgoing arguments at call. This method must be 1983 // called with a frame corresponding to a Java invoke 1984 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { 1985 #ifndef SHARK 1986 if (!method()->is_native()) { 1987 SimpleScopeDesc ssd(this, fr.pc()); 1988 Bytecode_invoke call(ssd.method(), ssd.bci()); 1989 bool has_receiver = call.has_receiver(); 1990 bool has_appendix = call.has_appendix(); 1991 Symbol* signature = call.signature(); 1992 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f); 1993 } 1994 #endif // !SHARK 1995 } 1996 1997 1998 oop nmethod::embeddedOop_at(u_char* p) { 1999 RelocIterator iter(this, p, p + 1); 2000 while (iter.next()) 2001 if (iter.type() == relocInfo::oop_type) { 2002 return iter.oop_reloc()->oop_value(); 2003 } 2004 return NULL; 2005 } 2006 2007 2008 inline bool includes(void* p, void* from, void* to) { 2009 return from <= p && p < to; 2010 } 2011 2012 2013 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) { 2014 assert(count >= 2, "must be sentinel values, at least"); 2015 2016 #ifdef ASSERT 2017 // must be sorted and unique; we do a binary search in find_pc_desc() 2018 int prev_offset = pcs[0].pc_offset(); 2019 assert(prev_offset == PcDesc::lower_offset_limit, 2020 "must start with a sentinel"); 2021 for (int i = 1; i < count; i++) { 2022 int this_offset = pcs[i].pc_offset(); 2023 assert(this_offset > prev_offset, "offsets must be sorted"); 2024 prev_offset = this_offset; 2025 } 2026 assert(prev_offset == PcDesc::upper_offset_limit, 2027 "must end with a sentinel"); 2028 #endif //ASSERT 2029 2030 // Search for MethodHandle invokes and tag the nmethod. 2031 for (int i = 0; i < count; i++) { 2032 if (pcs[i].is_method_handle_invoke()) { 2033 set_has_method_handle_invokes(true); 2034 break; 2035 } 2036 } 2037 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler"); 2038 2039 int size = count * sizeof(PcDesc); 2040 assert(scopes_pcs_size() >= size, "oob"); 2041 memcpy(scopes_pcs_begin(), pcs, size); 2042 2043 // Adjust the final sentinel downward. 2044 PcDesc* last_pc = &scopes_pcs_begin()[count-1]; 2045 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity"); 2046 last_pc->set_pc_offset(content_size() + 1); 2047 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { 2048 // Fill any rounding gaps with copies of the last record. 2049 last_pc[1] = last_pc[0]; 2050 } 2051 // The following assert could fail if sizeof(PcDesc) is not 2052 // an integral multiple of oopSize (the rounding term). 2053 // If it fails, change the logic to always allocate a multiple 2054 // of sizeof(PcDesc), and fill unused words with copies of *last_pc. 2055 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly"); 2056 } 2057 2058 void nmethod::copy_scopes_data(u_char* buffer, int size) { 2059 assert(scopes_data_size() >= size, "oob"); 2060 memcpy(scopes_data_begin(), buffer, size); 2061 } 2062 2063 2064 #ifdef ASSERT 2065 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) { 2066 PcDesc* lower = nm->scopes_pcs_begin(); 2067 PcDesc* upper = nm->scopes_pcs_end(); 2068 lower += 1; // exclude initial sentinel 2069 PcDesc* res = NULL; 2070 for (PcDesc* p = lower; p < upper; p++) { 2071 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc 2072 if (match_desc(p, pc_offset, approximate)) { 2073 if (res == NULL) 2074 res = p; 2075 else 2076 res = (PcDesc*) badAddress; 2077 } 2078 } 2079 return res; 2080 } 2081 #endif 2082 2083 2084 // Finds a PcDesc with real-pc equal to "pc" 2085 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) { 2086 address base_address = code_begin(); 2087 if ((pc < base_address) || 2088 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { 2089 return NULL; // PC is wildly out of range 2090 } 2091 int pc_offset = (int) (pc - base_address); 2092 2093 // Check the PcDesc cache if it contains the desired PcDesc 2094 // (This as an almost 100% hit rate.) 2095 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); 2096 if (res != NULL) { 2097 assert(res == linear_search(this, pc_offset, approximate), "cache ok"); 2098 return res; 2099 } 2100 2101 // Fallback algorithm: quasi-linear search for the PcDesc 2102 // Find the last pc_offset less than the given offset. 2103 // The successor must be the required match, if there is a match at all. 2104 // (Use a fixed radix to avoid expensive affine pointer arithmetic.) 2105 PcDesc* lower = scopes_pcs_begin(); 2106 PcDesc* upper = scopes_pcs_end(); 2107 upper -= 1; // exclude final sentinel 2108 if (lower >= upper) return NULL; // native method; no PcDescs at all 2109 2110 #define assert_LU_OK \ 2111 /* invariant on lower..upper during the following search: */ \ 2112 assert(lower->pc_offset() < pc_offset, "sanity"); \ 2113 assert(upper->pc_offset() >= pc_offset, "sanity") 2114 assert_LU_OK; 2115 2116 // Use the last successful return as a split point. 2117 PcDesc* mid = _pc_desc_cache.last_pc_desc(); 2118 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2119 if (mid->pc_offset() < pc_offset) { 2120 lower = mid; 2121 } else { 2122 upper = mid; 2123 } 2124 2125 // Take giant steps at first (4096, then 256, then 16, then 1) 2126 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); 2127 const int RADIX = (1 << LOG2_RADIX); 2128 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { 2129 while ((mid = lower + step) < upper) { 2130 assert_LU_OK; 2131 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2132 if (mid->pc_offset() < pc_offset) { 2133 lower = mid; 2134 } else { 2135 upper = mid; 2136 break; 2137 } 2138 } 2139 assert_LU_OK; 2140 } 2141 2142 // Sneak up on the value with a linear search of length ~16. 2143 while (true) { 2144 assert_LU_OK; 2145 mid = lower + 1; 2146 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2147 if (mid->pc_offset() < pc_offset) { 2148 lower = mid; 2149 } else { 2150 upper = mid; 2151 break; 2152 } 2153 } 2154 #undef assert_LU_OK 2155 2156 if (match_desc(upper, pc_offset, approximate)) { 2157 assert(upper == linear_search(this, pc_offset, approximate), "search ok"); 2158 _pc_desc_cache.add_pc_desc(upper); 2159 return upper; 2160 } else { 2161 assert(NULL == linear_search(this, pc_offset, approximate), "search ok"); 2162 return NULL; 2163 } 2164 } 2165 2166 2167 bool nmethod::check_all_dependencies() { 2168 bool found_check = false; 2169 // wholesale check of all dependencies 2170 for (Dependencies::DepStream deps(this); deps.next(); ) { 2171 if (deps.check_dependency() != NULL) { 2172 found_check = true; 2173 NOT_DEBUG(break); 2174 } 2175 } 2176 return found_check; // tell caller if we found anything 2177 } 2178 2179 bool nmethod::check_dependency_on(DepChange& changes) { 2180 // What has happened: 2181 // 1) a new class dependee has been added 2182 // 2) dependee and all its super classes have been marked 2183 bool found_check = false; // set true if we are upset 2184 for (Dependencies::DepStream deps(this); deps.next(); ) { 2185 // Evaluate only relevant dependencies. 2186 if (deps.spot_check_dependency_at(changes) != NULL) { 2187 found_check = true; 2188 NOT_DEBUG(break); 2189 } 2190 } 2191 return found_check; 2192 } 2193 2194 bool nmethod::is_evol_dependent_on(Klass* dependee) { 2195 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee); 2196 Array<Method*>* dependee_methods = dependee_ik->methods(); 2197 for (Dependencies::DepStream deps(this); deps.next(); ) { 2198 if (deps.type() == Dependencies::evol_method) { 2199 Method* method = deps.method_argument(0); 2200 for (int j = 0; j < dependee_methods->length(); j++) { 2201 if (dependee_methods->at(j) == method) { 2202 // RC_TRACE macro has an embedded ResourceMark 2203 RC_TRACE(0x01000000, 2204 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)", 2205 _method->method_holder()->external_name(), 2206 _method->name()->as_C_string(), 2207 _method->signature()->as_C_string(), compile_id(), 2208 method->method_holder()->external_name(), 2209 method->name()->as_C_string(), 2210 method->signature()->as_C_string())); 2211 if (TraceDependencies || LogCompilation) 2212 deps.log_dependency(dependee); 2213 return true; 2214 } 2215 } 2216 } 2217 } 2218 return false; 2219 } 2220 2221 // Called from mark_for_deoptimization, when dependee is invalidated. 2222 bool nmethod::is_dependent_on_method(Method* dependee) { 2223 for (Dependencies::DepStream deps(this); deps.next(); ) { 2224 if (deps.type() != Dependencies::evol_method) 2225 continue; 2226 Method* method = deps.method_argument(0); 2227 if (method == dependee) return true; 2228 } 2229 return false; 2230 } 2231 2232 2233 bool nmethod::is_patchable_at(address instr_addr) { 2234 assert(insts_contains(instr_addr), "wrong nmethod used"); 2235 if (is_zombie()) { 2236 // a zombie may never be patched 2237 return false; 2238 } 2239 return true; 2240 } 2241 2242 2243 address nmethod::continuation_for_implicit_exception(address pc) { 2244 // Exception happened outside inline-cache check code => we are inside 2245 // an active nmethod => use cpc to determine a return address 2246 int exception_offset = pc - code_begin(); 2247 int cont_offset = ImplicitExceptionTable(this).at( exception_offset ); 2248 #ifdef ASSERT 2249 if (cont_offset == 0) { 2250 Thread* thread = ThreadLocalStorage::get_thread_slow(); 2251 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY 2252 HandleMark hm(thread); 2253 ResourceMark rm(thread); 2254 CodeBlob* cb = CodeCache::find_blob(pc); 2255 assert(cb != NULL && cb == this, ""); 2256 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc); 2257 print(); 2258 method()->print_codes(); 2259 print_code(); 2260 print_pcs(); 2261 } 2262 #endif 2263 if (cont_offset == 0) { 2264 // Let the normal error handling report the exception 2265 return NULL; 2266 } 2267 return code_begin() + cont_offset; 2268 } 2269 2270 2271 2272 void nmethod_init() { 2273 // make sure you didn't forget to adjust the filler fields 2274 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word"); 2275 } 2276 2277 2278 //------------------------------------------------------------------------------------------- 2279 2280 2281 // QQQ might we make this work from a frame?? 2282 nmethodLocker::nmethodLocker(address pc) { 2283 CodeBlob* cb = CodeCache::find_blob(pc); 2284 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found"); 2285 _nm = (nmethod*)cb; 2286 lock_nmethod(_nm); 2287 } 2288 2289 // Only JvmtiDeferredEvent::compiled_method_unload_event() 2290 // should pass zombie_ok == true. 2291 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) { 2292 if (nm == NULL) return; 2293 Atomic::inc(&nm->_lock_count); 2294 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method"); 2295 } 2296 2297 void nmethodLocker::unlock_nmethod(nmethod* nm) { 2298 if (nm == NULL) return; 2299 Atomic::dec(&nm->_lock_count); 2300 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock"); 2301 } 2302 2303 2304 // ----------------------------------------------------------------------------- 2305 // nmethod::get_deopt_original_pc 2306 // 2307 // Return the original PC for the given PC if: 2308 // (a) the given PC belongs to a nmethod and 2309 // (b) it is a deopt PC 2310 address nmethod::get_deopt_original_pc(const frame* fr) { 2311 if (fr->cb() == NULL) return NULL; 2312 2313 nmethod* nm = fr->cb()->as_nmethod_or_null(); 2314 if (nm != NULL && nm->is_deopt_pc(fr->pc())) 2315 return nm->get_original_pc(fr); 2316 2317 return NULL; 2318 } 2319 2320 2321 // ----------------------------------------------------------------------------- 2322 // MethodHandle 2323 2324 bool nmethod::is_method_handle_return(address return_pc) { 2325 if (!has_method_handle_invokes()) return false; 2326 PcDesc* pd = pc_desc_at(return_pc); 2327 if (pd == NULL) 2328 return false; 2329 return pd->is_method_handle_invoke(); 2330 } 2331 2332 2333 // ----------------------------------------------------------------------------- 2334 // Verification 2335 2336 class VerifyOopsClosure: public OopClosure { 2337 nmethod* _nm; 2338 bool _ok; 2339 public: 2340 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } 2341 bool ok() { return _ok; } 2342 virtual void do_oop(oop* p) { 2343 if ((*p) == NULL || (*p)->is_oop()) return; 2344 if (_ok) { 2345 _nm->print_nmethod(true); 2346 _ok = false; 2347 } 2348 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2349 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2350 } 2351 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2352 }; 2353 2354 void nmethod::verify() { 2355 2356 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant 2357 // seems odd. 2358 2359 if( is_zombie() || is_not_entrant() ) 2360 return; 2361 2362 // Make sure all the entry points are correctly aligned for patching. 2363 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point()); 2364 2365 // assert(method()->is_oop(), "must be valid"); 2366 2367 ResourceMark rm; 2368 2369 if (!CodeCache::contains(this)) { 2370 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this)); 2371 } 2372 2373 if(is_native_method() ) 2374 return; 2375 2376 nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); 2377 if (nm != this) { 2378 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", 2379 this)); 2380 } 2381 2382 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2383 if (! p->verify(this)) { 2384 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this); 2385 } 2386 } 2387 2388 VerifyOopsClosure voc(this); 2389 oops_do(&voc); 2390 assert(voc.ok(), "embedded oops must be OK"); 2391 verify_scavenge_root_oops(); 2392 2393 verify_scopes(); 2394 } 2395 2396 2397 void nmethod::verify_interrupt_point(address call_site) { 2398 // This code does not work in release mode since 2399 // owns_lock only is available in debug mode. 2400 CompiledIC* ic = NULL; 2401 Thread *cur = Thread::current(); 2402 if (CompiledIC_lock->owner() == cur || 2403 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) && 2404 SafepointSynchronize::is_at_safepoint())) { 2405 ic = CompiledIC_at(this, call_site); 2406 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 2407 } else { 2408 MutexLocker ml_verify (CompiledIC_lock); 2409 ic = CompiledIC_at(this, call_site); 2410 } 2411 PcDesc* pd = pc_desc_at(ic->end_of_call()); 2412 assert(pd != NULL, "PcDesc must exist"); 2413 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(), 2414 pd->obj_decode_offset(), pd->should_reexecute(), 2415 pd->return_oop()); 2416 !sd->is_top(); sd = sd->sender()) { 2417 sd->verify(); 2418 } 2419 } 2420 2421 void nmethod::verify_scopes() { 2422 if( !method() ) return; // Runtime stubs have no scope 2423 if (method()->is_native()) return; // Ignore stub methods. 2424 // iterate through all interrupt point 2425 // and verify the debug information is valid. 2426 RelocIterator iter((nmethod*)this); 2427 while (iter.next()) { 2428 address stub = NULL; 2429 switch (iter.type()) { 2430 case relocInfo::virtual_call_type: 2431 verify_interrupt_point(iter.addr()); 2432 break; 2433 case relocInfo::opt_virtual_call_type: 2434 stub = iter.opt_virtual_call_reloc()->static_stub(); 2435 verify_interrupt_point(iter.addr()); 2436 break; 2437 case relocInfo::static_call_type: 2438 stub = iter.static_call_reloc()->static_stub(); 2439 //verify_interrupt_point(iter.addr()); 2440 break; 2441 case relocInfo::runtime_call_type: 2442 address destination = iter.reloc()->value(); 2443 // Right now there is no way to find out which entries support 2444 // an interrupt point. It would be nice if we had this 2445 // information in a table. 2446 break; 2447 } 2448 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section"); 2449 } 2450 } 2451 2452 2453 // ----------------------------------------------------------------------------- 2454 // Non-product code 2455 #ifndef PRODUCT 2456 2457 class DebugScavengeRoot: public OopClosure { 2458 nmethod* _nm; 2459 bool _ok; 2460 public: 2461 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { } 2462 bool ok() { return _ok; } 2463 virtual void do_oop(oop* p) { 2464 if ((*p) == NULL || !(*p)->is_scavengable()) return; 2465 if (_ok) { 2466 _nm->print_nmethod(true); 2467 _ok = false; 2468 } 2469 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2470 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2471 (*p)->print(); 2472 } 2473 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2474 }; 2475 2476 void nmethod::verify_scavenge_root_oops() { 2477 if (!on_scavenge_root_list()) { 2478 // Actually look inside, to verify the claim that it's clean. 2479 DebugScavengeRoot debug_scavenge_root(this); 2480 oops_do(&debug_scavenge_root); 2481 if (!debug_scavenge_root.ok()) 2482 fatal("found an unadvertised bad scavengable oop in the code cache"); 2483 } 2484 assert(scavenge_root_not_marked(), ""); 2485 } 2486 2487 #endif // PRODUCT 2488 2489 // Printing operations 2490 2491 void nmethod::print() const { 2492 ResourceMark rm; 2493 ttyLocker ttyl; // keep the following output all in one block 2494 2495 tty->print("Compiled method "); 2496 2497 if (is_compiled_by_c1()) { 2498 tty->print("(c1) "); 2499 } else if (is_compiled_by_c2()) { 2500 tty->print("(c2) "); 2501 } else if (is_compiled_by_shark()) { 2502 tty->print("(shark) "); 2503 } else { 2504 tty->print("(nm) "); 2505 } 2506 2507 print_on(tty, NULL); 2508 2509 if (WizardMode) { 2510 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this); 2511 tty->print(" for method " INTPTR_FORMAT , (address)method()); 2512 tty->print(" { "); 2513 if (is_in_use()) tty->print("in_use "); 2514 if (is_not_entrant()) tty->print("not_entrant "); 2515 if (is_zombie()) tty->print("zombie "); 2516 if (is_unloaded()) tty->print("unloaded "); 2517 if (on_scavenge_root_list()) tty->print("scavenge_root "); 2518 tty->print_cr("}:"); 2519 } 2520 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2521 (address)this, 2522 (address)this + size(), 2523 size()); 2524 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2525 relocation_begin(), 2526 relocation_end(), 2527 relocation_size()); 2528 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2529 consts_begin(), 2530 consts_end(), 2531 consts_size()); 2532 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2533 insts_begin(), 2534 insts_end(), 2535 insts_size()); 2536 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2537 stub_begin(), 2538 stub_end(), 2539 stub_size()); 2540 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2541 oops_begin(), 2542 oops_end(), 2543 oops_size()); 2544 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2545 metadata_begin(), 2546 metadata_end(), 2547 metadata_size()); 2548 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2549 scopes_data_begin(), 2550 scopes_data_end(), 2551 scopes_data_size()); 2552 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2553 scopes_pcs_begin(), 2554 scopes_pcs_end(), 2555 scopes_pcs_size()); 2556 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2557 dependencies_begin(), 2558 dependencies_end(), 2559 dependencies_size()); 2560 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2561 handler_table_begin(), 2562 handler_table_end(), 2563 handler_table_size()); 2564 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2565 nul_chk_table_begin(), 2566 nul_chk_table_end(), 2567 nul_chk_table_size()); 2568 } 2569 2570 void nmethod::print_code() { 2571 HandleMark hm; 2572 ResourceMark m; 2573 Disassembler::decode(this); 2574 } 2575 2576 2577 #ifndef PRODUCT 2578 2579 void nmethod::print_scopes() { 2580 // Find the first pc desc for all scopes in the code and print it. 2581 ResourceMark rm; 2582 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2583 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) 2584 continue; 2585 2586 ScopeDesc* sd = scope_desc_at(p->real_pc(this)); 2587 sd->print_on(tty, p); 2588 } 2589 } 2590 2591 void nmethod::print_dependencies() { 2592 ResourceMark rm; 2593 ttyLocker ttyl; // keep the following output all in one block 2594 tty->print_cr("Dependencies:"); 2595 for (Dependencies::DepStream deps(this); deps.next(); ) { 2596 deps.print_dependency(); 2597 Klass* ctxk = deps.context_type(); 2598 if (ctxk != NULL) { 2599 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) { 2600 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name()); 2601 } 2602 } 2603 deps.log_dependency(); // put it into the xml log also 2604 } 2605 } 2606 2607 2608 void nmethod::print_relocations() { 2609 ResourceMark m; // in case methods get printed via the debugger 2610 tty->print_cr("relocations:"); 2611 RelocIterator iter(this); 2612 iter.print(); 2613 if (UseRelocIndex) { 2614 jint* index_end = (jint*)relocation_end() - 1; 2615 jint index_size = *index_end; 2616 jint* index_start = (jint*)( (address)index_end - index_size ); 2617 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size); 2618 if (index_size > 0) { 2619 jint* ip; 2620 for (ip = index_start; ip+2 <= index_end; ip += 2) 2621 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT, 2622 ip[0], 2623 ip[1], 2624 header_end()+ip[0], 2625 relocation_begin()-1+ip[1]); 2626 for (; ip < index_end; ip++) 2627 tty->print_cr(" (%d ?)", ip[0]); 2628 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip); 2629 ip++; 2630 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip); 2631 } 2632 } 2633 } 2634 2635 2636 void nmethod::print_pcs() { 2637 ResourceMark m; // in case methods get printed via debugger 2638 tty->print_cr("pc-bytecode offsets:"); 2639 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2640 p->print(this); 2641 } 2642 } 2643 2644 #endif // PRODUCT 2645 2646 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) { 2647 RelocIterator iter(this, begin, end); 2648 bool have_one = false; 2649 while (iter.next()) { 2650 have_one = true; 2651 switch (iter.type()) { 2652 case relocInfo::none: return "no_reloc"; 2653 case relocInfo::oop_type: { 2654 stringStream st; 2655 oop_Relocation* r = iter.oop_reloc(); 2656 oop obj = r->oop_value(); 2657 st.print("oop("); 2658 if (obj == NULL) st.print("NULL"); 2659 else obj->print_value_on(&st); 2660 st.print(")"); 2661 return st.as_string(); 2662 } 2663 case relocInfo::metadata_type: { 2664 stringStream st; 2665 metadata_Relocation* r = iter.metadata_reloc(); 2666 Metadata* obj = r->metadata_value(); 2667 st.print("metadata("); 2668 if (obj == NULL) st.print("NULL"); 2669 else obj->print_value_on(&st); 2670 st.print(")"); 2671 return st.as_string(); 2672 } 2673 case relocInfo::virtual_call_type: return "virtual_call"; 2674 case relocInfo::opt_virtual_call_type: return "optimized virtual_call"; 2675 case relocInfo::static_call_type: return "static_call"; 2676 case relocInfo::static_stub_type: return "static_stub"; 2677 case relocInfo::runtime_call_type: return "runtime_call"; 2678 case relocInfo::external_word_type: return "external_word"; 2679 case relocInfo::internal_word_type: return "internal_word"; 2680 case relocInfo::section_word_type: return "section_word"; 2681 case relocInfo::poll_type: return "poll"; 2682 case relocInfo::poll_return_type: return "poll_return"; 2683 case relocInfo::type_mask: return "type_bit_mask"; 2684 } 2685 } 2686 return have_one ? "other" : NULL; 2687 } 2688 2689 // Return a the last scope in (begin..end] 2690 ScopeDesc* nmethod::scope_desc_in(address begin, address end) { 2691 PcDesc* p = pc_desc_near(begin+1); 2692 if (p != NULL && p->real_pc(this) <= end) { 2693 return new ScopeDesc(this, p->scope_decode_offset(), 2694 p->obj_decode_offset(), p->should_reexecute(), 2695 p->return_oop()); 2696 } 2697 return NULL; 2698 } 2699 2700 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const { 2701 if (block_begin == entry_point()) stream->print_cr("[Entry Point]"); 2702 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]"); 2703 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]"); 2704 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]"); 2705 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]"); 2706 2707 if (has_method_handle_invokes()) 2708 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]"); 2709 2710 if (block_begin == consts_begin()) stream->print_cr("[Constants]"); 2711 2712 if (block_begin == entry_point()) { 2713 methodHandle m = method(); 2714 if (m.not_null()) { 2715 stream->print(" # "); 2716 m->print_value_on(stream); 2717 stream->cr(); 2718 } 2719 if (m.not_null() && !is_osr_method()) { 2720 ResourceMark rm; 2721 int sizeargs = m->size_of_parameters(); 2722 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs); 2723 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs); 2724 { 2725 int sig_index = 0; 2726 if (!m->is_static()) 2727 sig_bt[sig_index++] = T_OBJECT; // 'this' 2728 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) { 2729 BasicType t = ss.type(); 2730 sig_bt[sig_index++] = t; 2731 if (type2size[t] == 2) { 2732 sig_bt[sig_index++] = T_VOID; 2733 } else { 2734 assert(type2size[t] == 1, "size is 1 or 2"); 2735 } 2736 } 2737 assert(sig_index == sizeargs, ""); 2738 } 2739 const char* spname = "sp"; // make arch-specific? 2740 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false); 2741 int stack_slot_offset = this->frame_size() * wordSize; 2742 int tab1 = 14, tab2 = 24; 2743 int sig_index = 0; 2744 int arg_index = (m->is_static() ? 0 : -1); 2745 bool did_old_sp = false; 2746 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) { 2747 bool at_this = (arg_index == -1); 2748 bool at_old_sp = false; 2749 BasicType t = (at_this ? T_OBJECT : ss.type()); 2750 assert(t == sig_bt[sig_index], "sigs in sync"); 2751 if (at_this) 2752 stream->print(" # this: "); 2753 else 2754 stream->print(" # parm%d: ", arg_index); 2755 stream->move_to(tab1); 2756 VMReg fst = regs[sig_index].first(); 2757 VMReg snd = regs[sig_index].second(); 2758 if (fst->is_reg()) { 2759 stream->print("%s", fst->name()); 2760 if (snd->is_valid()) { 2761 stream->print(":%s", snd->name()); 2762 } 2763 } else if (fst->is_stack()) { 2764 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset; 2765 if (offset == stack_slot_offset) at_old_sp = true; 2766 stream->print("[%s+0x%x]", spname, offset); 2767 } else { 2768 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd); 2769 } 2770 stream->print(" "); 2771 stream->move_to(tab2); 2772 stream->print("= "); 2773 if (at_this) { 2774 m->method_holder()->print_value_on(stream); 2775 } else { 2776 bool did_name = false; 2777 if (!at_this && ss.is_object()) { 2778 Symbol* name = ss.as_symbol_or_null(); 2779 if (name != NULL) { 2780 name->print_value_on(stream); 2781 did_name = true; 2782 } 2783 } 2784 if (!did_name) 2785 stream->print("%s", type2name(t)); 2786 } 2787 if (at_old_sp) { 2788 stream->print(" (%s of caller)", spname); 2789 did_old_sp = true; 2790 } 2791 stream->cr(); 2792 sig_index += type2size[t]; 2793 arg_index += 1; 2794 if (!at_this) ss.next(); 2795 } 2796 if (!did_old_sp) { 2797 stream->print(" # "); 2798 stream->move_to(tab1); 2799 stream->print("[%s+0x%x]", spname, stack_slot_offset); 2800 stream->print(" (%s of caller)", spname); 2801 stream->cr(); 2802 } 2803 } 2804 } 2805 } 2806 2807 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) { 2808 // First, find an oopmap in (begin, end]. 2809 // We use the odd half-closed interval so that oop maps and scope descs 2810 // which are tied to the byte after a call are printed with the call itself. 2811 address base = code_begin(); 2812 OopMapSet* oms = oop_maps(); 2813 if (oms != NULL) { 2814 for (int i = 0, imax = oms->size(); i < imax; i++) { 2815 OopMap* om = oms->at(i); 2816 address pc = base + om->offset(); 2817 if (pc > begin) { 2818 if (pc <= end) { 2819 st->move_to(column); 2820 st->print("; "); 2821 om->print_on(st); 2822 } 2823 break; 2824 } 2825 } 2826 } 2827 2828 // Print any debug info present at this pc. 2829 ScopeDesc* sd = scope_desc_in(begin, end); 2830 if (sd != NULL) { 2831 st->move_to(column); 2832 if (sd->bci() == SynchronizationEntryBCI) { 2833 st->print(";*synchronization entry"); 2834 } else { 2835 if (sd->method() == NULL) { 2836 st->print("method is NULL"); 2837 } else if (sd->method()->is_native()) { 2838 st->print("method is native"); 2839 } else { 2840 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci()); 2841 st->print(";*%s", Bytecodes::name(bc)); 2842 switch (bc) { 2843 case Bytecodes::_invokevirtual: 2844 case Bytecodes::_invokespecial: 2845 case Bytecodes::_invokestatic: 2846 case Bytecodes::_invokeinterface: 2847 { 2848 Bytecode_invoke invoke(sd->method(), sd->bci()); 2849 st->print(" "); 2850 if (invoke.name() != NULL) 2851 invoke.name()->print_symbol_on(st); 2852 else 2853 st->print("<UNKNOWN>"); 2854 break; 2855 } 2856 case Bytecodes::_getfield: 2857 case Bytecodes::_putfield: 2858 case Bytecodes::_getstatic: 2859 case Bytecodes::_putstatic: 2860 { 2861 Bytecode_field field(sd->method(), sd->bci()); 2862 st->print(" "); 2863 if (field.name() != NULL) 2864 field.name()->print_symbol_on(st); 2865 else 2866 st->print("<UNKNOWN>"); 2867 } 2868 } 2869 } 2870 } 2871 2872 // Print all scopes 2873 for (;sd != NULL; sd = sd->sender()) { 2874 st->move_to(column); 2875 st->print("; -"); 2876 if (sd->method() == NULL) { 2877 st->print("method is NULL"); 2878 } else { 2879 sd->method()->print_short_name(st); 2880 } 2881 int lineno = sd->method()->line_number_from_bci(sd->bci()); 2882 if (lineno != -1) { 2883 st->print("@%d (line %d)", sd->bci(), lineno); 2884 } else { 2885 st->print("@%d", sd->bci()); 2886 } 2887 st->cr(); 2888 } 2889 } 2890 2891 // Print relocation information 2892 const char* str = reloc_string_for(begin, end); 2893 if (str != NULL) { 2894 if (sd != NULL) st->cr(); 2895 st->move_to(column); 2896 st->print("; {%s}", str); 2897 } 2898 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin()); 2899 if (cont_offset != 0) { 2900 st->move_to(column); 2901 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset); 2902 } 2903 2904 } 2905 2906 #ifndef PRODUCT 2907 2908 void nmethod::print_value_on(outputStream* st) const { 2909 st->print("nmethod"); 2910 print_on(st, NULL); 2911 } 2912 2913 void nmethod::print_calls(outputStream* st) { 2914 RelocIterator iter(this); 2915 while (iter.next()) { 2916 switch (iter.type()) { 2917 case relocInfo::virtual_call_type: 2918 case relocInfo::opt_virtual_call_type: { 2919 VerifyMutexLocker mc(CompiledIC_lock); 2920 CompiledIC_at(iter.reloc())->print(); 2921 break; 2922 } 2923 case relocInfo::static_call_type: 2924 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr()); 2925 compiledStaticCall_at(iter.reloc())->print(); 2926 break; 2927 } 2928 } 2929 } 2930 2931 void nmethod::print_handler_table() { 2932 ExceptionHandlerTable(this).print(); 2933 } 2934 2935 void nmethod::print_nul_chk_table() { 2936 ImplicitExceptionTable(this).print(code_begin()); 2937 } 2938 2939 void nmethod::print_statistics() { 2940 ttyLocker ttyl; 2941 if (xtty != NULL) xtty->head("statistics type='nmethod'"); 2942 nmethod_stats.print_native_nmethod_stats(); 2943 nmethod_stats.print_nmethod_stats(); 2944 DebugInformationRecorder::print_statistics(); 2945 nmethod_stats.print_pc_stats(); 2946 Dependencies::print_statistics(); 2947 if (xtty != NULL) xtty->tail("statistics"); 2948 } 2949 2950 #endif // PRODUCT