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