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 } 1088 1089 1090 void nmethod::verify_oop_relocations() { 1091 // Ensure sure that the code matches the current oop values 1092 RelocIterator iter(this, NULL, NULL); 1093 while (iter.next()) { 1094 if (iter.type() == relocInfo::oop_type) { 1095 oop_Relocation* reloc = iter.oop_reloc(); 1096 if (!reloc->oop_is_immediate()) { 1097 reloc->verify_oop_relocation(); 1098 } 1099 } 1100 } 1101 } 1102 1103 1104 ScopeDesc* nmethod::scope_desc_at(address pc) { 1105 PcDesc* pd = pc_desc_at(pc); 1106 guarantee(pd != NULL, "scope must be present"); 1107 return new ScopeDesc(this, pd->scope_decode_offset(), 1108 pd->obj_decode_offset(), pd->should_reexecute(), 1109 pd->return_oop()); 1110 } 1111 1112 1113 void nmethod::clear_inline_caches() { 1114 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint"); 1115 if (is_zombie()) { 1116 return; 1117 } 1118 1119 RelocIterator iter(this); 1120 while (iter.next()) { 1121 iter.reloc()->clear_inline_cache(); 1122 } 1123 } 1124 1125 1126 void nmethod::cleanup_inline_caches() { 1127 1128 assert_locked_or_safepoint(CompiledIC_lock); 1129 1130 // If the method is not entrant or zombie then a JMP is plastered over the 1131 // first few bytes. If an oop in the old code was there, that oop 1132 // should not get GC'd. Skip the first few bytes of oops on 1133 // not-entrant methods. 1134 address low_boundary = verified_entry_point(); 1135 if (!is_in_use()) { 1136 low_boundary += NativeJump::instruction_size; 1137 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1138 // This means that the low_boundary is going to be a little too high. 1139 // This shouldn't matter, since oops of non-entrant methods are never used. 1140 // In fact, why are we bothering to look at oops in a non-entrant method?? 1141 } 1142 1143 // Find all calls in an nmethod, and clear the ones that points to zombie methods 1144 ResourceMark rm; 1145 RelocIterator iter(this, low_boundary); 1146 while(iter.next()) { 1147 switch(iter.type()) { 1148 case relocInfo::virtual_call_type: 1149 case relocInfo::opt_virtual_call_type: { 1150 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1151 // Ok, to lookup references to zombies here 1152 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1153 if( cb != NULL && cb->is_nmethod() ) { 1154 nmethod* nm = (nmethod*)cb; 1155 // Clean inline caches pointing to both zombie and not_entrant methods 1156 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(); 1157 } 1158 break; 1159 } 1160 case relocInfo::static_call_type: { 1161 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1162 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1163 if( cb != NULL && cb->is_nmethod() ) { 1164 nmethod* nm = (nmethod*)cb; 1165 // Clean inline caches pointing to both zombie and not_entrant methods 1166 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean(); 1167 } 1168 break; 1169 } 1170 } 1171 } 1172 } 1173 1174 // This is a private interface with the sweeper. 1175 void nmethod::mark_as_seen_on_stack() { 1176 assert(is_not_entrant(), "must be a non-entrant method"); 1177 // Set the traversal mark to ensure that the sweeper does 2 1178 // cleaning passes before moving to zombie. 1179 set_stack_traversal_mark(NMethodSweeper::traversal_count()); 1180 } 1181 1182 // Tell if a non-entrant method can be converted to a zombie (i.e., 1183 // there are no activations on the stack, not in use by the VM, 1184 // and not in use by the ServiceThread) 1185 bool nmethod::can_not_entrant_be_converted() { 1186 assert(is_not_entrant(), "must be a non-entrant method"); 1187 1188 // Since the nmethod sweeper only does partial sweep the sweeper's traversal 1189 // count can be greater than the stack traversal count before it hits the 1190 // nmethod for the second time. 1191 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() && 1192 !is_locked_by_vm(); 1193 } 1194 1195 void nmethod::inc_decompile_count() { 1196 if (!is_compiled_by_c2()) return; 1197 // Could be gated by ProfileTraps, but do not bother... 1198 Method* m = method(); 1199 if (m == NULL) return; 1200 MethodData* mdo = m->method_data(); 1201 if (mdo == NULL) return; 1202 // There is a benign race here. See comments in methodData.hpp. 1203 mdo->inc_decompile_count(); 1204 } 1205 1206 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) { 1207 1208 post_compiled_method_unload(); 1209 1210 // Since this nmethod is being unloaded, make sure that dependencies 1211 // recorded in instanceKlasses get flushed and pass non-NULL closure to 1212 // indicate that this work is being done during a GC. 1213 assert(Universe::heap()->is_gc_active(), "should only be called during gc"); 1214 assert(is_alive != NULL, "Should be non-NULL"); 1215 // A non-NULL is_alive closure indicates that this is being called during GC. 1216 flush_dependencies(is_alive); 1217 1218 // Break cycle between nmethod & method 1219 if (TraceClassUnloading && WizardMode) { 1220 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT 1221 " unloadable], Method*(" INTPTR_FORMAT 1222 "), cause(" INTPTR_FORMAT ")", 1223 this, (address)_method, (address)cause); 1224 if (!Universe::heap()->is_gc_active()) 1225 cause->klass()->print(); 1226 } 1227 // Unlink the osr method, so we do not look this up again 1228 if (is_osr_method()) { 1229 invalidate_osr_method(); 1230 } 1231 // If _method is already NULL the Method* is about to be unloaded, 1232 // so we don't have to break the cycle. Note that it is possible to 1233 // have the Method* live here, in case we unload the nmethod because 1234 // it is pointing to some oop (other than the Method*) being unloaded. 1235 if (_method != NULL) { 1236 // OSR methods point to the Method*, but the Method* does not 1237 // point back! 1238 if (_method->code() == this) { 1239 _method->clear_code(); // Break a cycle 1240 } 1241 _method = NULL; // Clear the method of this dead nmethod 1242 } 1243 // Make the class unloaded - i.e., change state and notify sweeper 1244 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1245 if (is_in_use()) { 1246 // Transitioning directly from live to unloaded -- so 1247 // we need to force a cache clean-up; remember this 1248 // for later on. 1249 CodeCache::set_needs_cache_clean(true); 1250 } 1251 _state = unloaded; 1252 1253 // Log the unloading. 1254 log_state_change(); 1255 1256 // The Method* is gone at this point 1257 assert(_method == NULL, "Tautology"); 1258 1259 set_osr_link(NULL); 1260 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods 1261 NMethodSweeper::notify(this); 1262 } 1263 1264 void nmethod::invalidate_osr_method() { 1265 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); 1266 // Remove from list of active nmethods 1267 if (method() != NULL) 1268 method()->method_holder()->remove_osr_nmethod(this); 1269 // Set entry as invalid 1270 _entry_bci = InvalidOSREntryBci; 1271 } 1272 1273 void nmethod::log_state_change() const { 1274 if (LogCompilation) { 1275 if (xtty != NULL) { 1276 ttyLocker ttyl; // keep the following output all in one block 1277 if (_state == unloaded) { 1278 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'", 1279 os::current_thread_id()); 1280 } else { 1281 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s", 1282 os::current_thread_id(), 1283 (_state == zombie ? " zombie='1'" : "")); 1284 } 1285 log_identity(xtty); 1286 xtty->stamp(); 1287 xtty->end_elem(); 1288 } 1289 } 1290 if (PrintCompilation && _state != unloaded) { 1291 print_on(tty, _state == zombie ? "made zombie" : "made not entrant"); 1292 } 1293 } 1294 1295 // Common functionality for both make_not_entrant and make_zombie 1296 bool nmethod::make_not_entrant_or_zombie(unsigned int state) { 1297 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant"); 1298 assert(!is_zombie(), "should not already be a zombie"); 1299 1300 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below. 1301 nmethodLocker nml(this); 1302 methodHandle the_method(method()); 1303 No_Safepoint_Verifier nsv; 1304 1305 // during patching, depending on the nmethod state we must notify the GC that 1306 // code has been unloaded, unregistering it. We cannot do this right while 1307 // holding the Patching_lock because we need to use the CodeCache_lock. This 1308 // would be prone to deadlocks. 1309 // This flag is used to remember whether we need to later lock and unregister. 1310 bool nmethod_needs_unregister = false; 1311 1312 { 1313 // invalidate osr nmethod before acquiring the patching lock since 1314 // they both acquire leaf locks and we don't want a deadlock. 1315 // This logic is equivalent to the logic below for patching the 1316 // verified entry point of regular methods. 1317 if (is_osr_method()) { 1318 // this effectively makes the osr nmethod not entrant 1319 invalidate_osr_method(); 1320 } 1321 1322 // Enter critical section. Does not block for safepoint. 1323 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1324 1325 if (_state == state) { 1326 // another thread already performed this transition so nothing 1327 // to do, but return false to indicate this. 1328 return false; 1329 } 1330 1331 // The caller can be calling the method statically or through an inline 1332 // cache call. 1333 if (!is_osr_method() && !is_not_entrant()) { 1334 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(), 1335 SharedRuntime::get_handle_wrong_method_stub()); 1336 } 1337 1338 if (is_in_use()) { 1339 // It's a true state change, so mark the method as decompiled. 1340 // Do it only for transition from alive. 1341 inc_decompile_count(); 1342 } 1343 1344 // If the state is becoming a zombie, signal to unregister the nmethod with 1345 // the heap. 1346 // This nmethod may have already been unloaded during a full GC. 1347 if ((state == zombie) && !is_unloaded()) { 1348 nmethod_needs_unregister = true; 1349 } 1350 1351 // Change state 1352 _state = state; 1353 1354 // Log the transition once 1355 log_state_change(); 1356 1357 // Remove nmethod from method. 1358 // We need to check if both the _code and _from_compiled_code_entry_point 1359 // refer to this nmethod because there is a race in setting these two fields 1360 // in Method* as seen in bugid 4947125. 1361 // If the vep() points to the zombie nmethod, the memory for the nmethod 1362 // could be flushed and the compiler and vtable stubs could still call 1363 // through it. 1364 if (method() != NULL && (method()->code() == this || 1365 method()->from_compiled_entry() == verified_entry_point())) { 1366 HandleMark hm; 1367 method()->clear_code(); 1368 } 1369 1370 if (state == not_entrant) { 1371 mark_as_seen_on_stack(); 1372 } 1373 1374 } // leave critical region under Patching_lock 1375 1376 // When the nmethod becomes zombie it is no longer alive so the 1377 // dependencies must be flushed. nmethods in the not_entrant 1378 // state will be flushed later when the transition to zombie 1379 // happens or they get unloaded. 1380 if (state == zombie) { 1381 { 1382 // Flushing dependecies must be done before any possible 1383 // safepoint can sneak in, otherwise the oops used by the 1384 // dependency logic could have become stale. 1385 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1386 if (nmethod_needs_unregister) { 1387 Universe::heap()->unregister_nmethod(this); 1388 } 1389 flush_dependencies(NULL); 1390 } 1391 1392 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload 1393 // event and it hasn't already been reported for this nmethod then 1394 // report it now. The event may have been reported earilier if the GC 1395 // marked it for unloading). JvmtiDeferredEventQueue support means 1396 // we no longer go to a safepoint here. 1397 post_compiled_method_unload(); 1398 1399 #ifdef ASSERT 1400 // It's no longer safe to access the oops section since zombie 1401 // nmethods aren't scanned for GC. 1402 _oops_are_stale = true; 1403 #endif 1404 } else { 1405 assert(state == not_entrant, "other cases may need to be handled differently"); 1406 } 1407 1408 if (TraceCreateZombies) { 1409 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie"); 1410 } 1411 1412 // Make sweeper aware that there is a zombie method that needs to be removed 1413 NMethodSweeper::notify(this); 1414 1415 return true; 1416 } 1417 1418 void nmethod::flush() { 1419 // Note that there are no valid oops in the nmethod anymore. 1420 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method"); 1421 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation"); 1422 1423 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed"); 1424 assert_locked_or_safepoint(CodeCache_lock); 1425 1426 // completely deallocate this method 1427 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this); 1428 if (PrintMethodFlushing) { 1429 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb", 1430 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024); 1431 } 1432 1433 // We need to deallocate any ExceptionCache data. 1434 // Note that we do not need to grab the nmethod lock for this, it 1435 // better be thread safe if we're disposing of it! 1436 ExceptionCache* ec = exception_cache(); 1437 set_exception_cache(NULL); 1438 while(ec != NULL) { 1439 ExceptionCache* next = ec->next(); 1440 delete ec; 1441 ec = next; 1442 } 1443 1444 if (on_scavenge_root_list()) { 1445 CodeCache::drop_scavenge_root_nmethod(this); 1446 } 1447 1448 if (is_speculatively_disconnected()) { 1449 CodeCache::remove_saved_code(this); 1450 } 1451 1452 #ifdef SHARK 1453 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin()); 1454 #endif // SHARK 1455 1456 ((CodeBlob*)(this))->flush(); 1457 1458 CodeCache::free(this); 1459 } 1460 1461 1462 // 1463 // Notify all classes this nmethod is dependent on that it is no 1464 // longer dependent. This should only be called in two situations. 1465 // First, when a nmethod transitions to a zombie all dependents need 1466 // to be clear. Since zombification happens at a safepoint there's no 1467 // synchronization issues. The second place is a little more tricky. 1468 // During phase 1 of mark sweep class unloading may happen and as a 1469 // result some nmethods may get unloaded. In this case the flushing 1470 // of dependencies must happen during phase 1 since after GC any 1471 // dependencies in the unloaded nmethod won't be updated, so 1472 // traversing the dependency information in unsafe. In that case this 1473 // function is called with a non-NULL argument and this function only 1474 // notifies instanceKlasses that are reachable 1475 1476 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) { 1477 assert_locked_or_safepoint(CodeCache_lock); 1478 assert(Universe::heap()->is_gc_active() == (is_alive != NULL), 1479 "is_alive is non-NULL if and only if we are called during GC"); 1480 if (!has_flushed_dependencies()) { 1481 set_has_flushed_dependencies(); 1482 for (Dependencies::DepStream deps(this); deps.next(); ) { 1483 Klass* klass = deps.context_type(); 1484 if (klass == NULL) continue; // ignore things like evol_method 1485 1486 // During GC the is_alive closure is non-NULL, and is used to 1487 // determine liveness of dependees that need to be updated. 1488 if (is_alive == NULL || klass->is_loader_alive(is_alive)) { 1489 InstanceKlass::cast(klass)->remove_dependent_nmethod(this); 1490 } 1491 } 1492 } 1493 } 1494 1495 1496 // If this oop is not live, the nmethod can be unloaded. 1497 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) { 1498 assert(root != NULL, "just checking"); 1499 oop obj = *root; 1500 if (obj == NULL || is_alive->do_object_b(obj)) { 1501 return false; 1502 } 1503 1504 // If ScavengeRootsInCode is true, an nmethod might be unloaded 1505 // simply because one of its constant oops has gone dead. 1506 // No actual classes need to be unloaded in order for this to occur. 1507 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading"); 1508 make_unloaded(is_alive, obj); 1509 return true; 1510 } 1511 1512 // ------------------------------------------------------------------ 1513 // post_compiled_method_load_event 1514 // new method for install_code() path 1515 // Transfer information from compilation to jvmti 1516 void nmethod::post_compiled_method_load_event() { 1517 1518 Method* moop = method(); 1519 #ifndef USDT2 1520 HS_DTRACE_PROBE8(hotspot, compiled__method__load, 1521 moop->klass_name()->bytes(), 1522 moop->klass_name()->utf8_length(), 1523 moop->name()->bytes(), 1524 moop->name()->utf8_length(), 1525 moop->signature()->bytes(), 1526 moop->signature()->utf8_length(), 1527 insts_begin(), insts_size()); 1528 #else /* USDT2 */ 1529 HOTSPOT_COMPILED_METHOD_LOAD( 1530 (char *) moop->klass_name()->bytes(), 1531 moop->klass_name()->utf8_length(), 1532 (char *) moop->name()->bytes(), 1533 moop->name()->utf8_length(), 1534 (char *) moop->signature()->bytes(), 1535 moop->signature()->utf8_length(), 1536 insts_begin(), insts_size()); 1537 #endif /* USDT2 */ 1538 1539 if (JvmtiExport::should_post_compiled_method_load() || 1540 JvmtiExport::should_post_compiled_method_unload()) { 1541 get_and_cache_jmethod_id(); 1542 } 1543 1544 if (JvmtiExport::should_post_compiled_method_load()) { 1545 // Let the Service thread (which is a real Java thread) post the event 1546 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1547 JvmtiDeferredEventQueue::enqueue( 1548 JvmtiDeferredEvent::compiled_method_load_event(this)); 1549 } 1550 } 1551 1552 jmethodID nmethod::get_and_cache_jmethod_id() { 1553 if (_jmethod_id == NULL) { 1554 // Cache the jmethod_id since it can no longer be looked up once the 1555 // method itself has been marked for unloading. 1556 _jmethod_id = method()->jmethod_id(); 1557 } 1558 return _jmethod_id; 1559 } 1560 1561 void nmethod::post_compiled_method_unload() { 1562 if (unload_reported()) { 1563 // During unloading we transition to unloaded and then to zombie 1564 // and the unloading is reported during the first transition. 1565 return; 1566 } 1567 1568 assert(_method != NULL && !is_unloaded(), "just checking"); 1569 DTRACE_METHOD_UNLOAD_PROBE(method()); 1570 1571 // If a JVMTI agent has enabled the CompiledMethodUnload event then 1572 // post the event. Sometime later this nmethod will be made a zombie 1573 // by the sweeper but the Method* will not be valid at that point. 1574 // If the _jmethod_id is null then no load event was ever requested 1575 // so don't bother posting the unload. The main reason for this is 1576 // that the jmethodID is a weak reference to the Method* so if 1577 // it's being unloaded there's no way to look it up since the weak 1578 // ref will have been cleared. 1579 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) { 1580 assert(!unload_reported(), "already unloaded"); 1581 JvmtiDeferredEvent event = 1582 JvmtiDeferredEvent::compiled_method_unload_event(this, 1583 _jmethod_id, insts_begin()); 1584 if (SafepointSynchronize::is_at_safepoint()) { 1585 // Don't want to take the queueing lock. Add it as pending and 1586 // it will get enqueued later. 1587 JvmtiDeferredEventQueue::add_pending_event(event); 1588 } else { 1589 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1590 JvmtiDeferredEventQueue::enqueue(event); 1591 } 1592 } 1593 1594 // The JVMTI CompiledMethodUnload event can be enabled or disabled at 1595 // any time. As the nmethod is being unloaded now we mark it has 1596 // having the unload event reported - this will ensure that we don't 1597 // attempt to report the event in the unlikely scenario where the 1598 // event is enabled at the time the nmethod is made a zombie. 1599 set_unload_reported(); 1600 } 1601 1602 // This is called at the end of the strong tracing/marking phase of a 1603 // GC to unload an nmethod if it contains otherwise unreachable 1604 // oops. 1605 1606 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) { 1607 // Make sure the oop's ready to receive visitors 1608 assert(!is_zombie() && !is_unloaded(), 1609 "should not call follow on zombie or unloaded nmethod"); 1610 1611 // If the method is not entrant then a JMP is plastered over the 1612 // first few bytes. If an oop in the old code was there, that oop 1613 // should not get GC'd. Skip the first few bytes of oops on 1614 // not-entrant methods. 1615 address low_boundary = verified_entry_point(); 1616 if (is_not_entrant()) { 1617 low_boundary += NativeJump::instruction_size; 1618 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1619 // (See comment above.) 1620 } 1621 1622 // The RedefineClasses() API can cause the class unloading invariant 1623 // to no longer be true. See jvmtiExport.hpp for details. 1624 // Also, leave a debugging breadcrumb in local flag. 1625 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class(); 1626 if (a_class_was_redefined) { 1627 // This set of the unloading_occurred flag is done before the 1628 // call to post_compiled_method_unload() so that the unloading 1629 // of this nmethod is reported. 1630 unloading_occurred = true; 1631 } 1632 1633 // Exception cache 1634 ExceptionCache* ec = exception_cache(); 1635 while (ec != NULL) { 1636 Klass* ex_klass = ec->exception_type(); 1637 ExceptionCache* next_ec = ec->next(); 1638 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) { 1639 remove_from_exception_cache(ec); 1640 } 1641 ec = next_ec; 1642 } 1643 1644 // If class unloading occurred we first iterate over all inline caches and 1645 // clear ICs where the cached oop is referring to an unloaded klass or method. 1646 // The remaining live cached oops will be traversed in the relocInfo::oop_type 1647 // iteration below. 1648 if (unloading_occurred) { 1649 RelocIterator iter(this, low_boundary); 1650 while(iter.next()) { 1651 if (iter.type() == relocInfo::virtual_call_type) { 1652 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1653 if (ic->is_icholder_call()) { 1654 // The only exception is compiledICHolder oops which may 1655 // yet be marked below. (We check this further below). 1656 CompiledICHolder* cichk_oop = ic->cached_icholder(); 1657 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) && 1658 cichk_oop->holder_klass()->is_loader_alive(is_alive)) { 1659 continue; 1660 } 1661 } else { 1662 Metadata* ic_oop = ic->cached_metadata(); 1663 if (ic_oop != NULL) { 1664 if (ic_oop->is_klass()) { 1665 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) { 1666 continue; 1667 } 1668 } else if (ic_oop->is_method()) { 1669 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) { 1670 continue; 1671 } 1672 } else { 1673 ShouldNotReachHere(); 1674 } 1675 } 1676 } 1677 ic->set_to_clean(); 1678 } 1679 } 1680 } 1681 1682 // Compiled code 1683 { 1684 RelocIterator iter(this, low_boundary); 1685 while (iter.next()) { 1686 if (iter.type() == relocInfo::oop_type) { 1687 oop_Relocation* r = iter.oop_reloc(); 1688 // In this loop, we must only traverse those oops directly embedded in 1689 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1690 assert(1 == (r->oop_is_immediate()) + 1691 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1692 "oop must be found in exactly one place"); 1693 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1694 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) { 1695 return; 1696 } 1697 } 1698 } 1699 } 1700 } 1701 1702 1703 // Scopes 1704 for (oop* p = oops_begin(); p < oops_end(); p++) { 1705 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1706 if (can_unload(is_alive, p, unloading_occurred)) { 1707 return; 1708 } 1709 } 1710 1711 // Ensure that all metadata is still alive 1712 verify_metadata_loaders(low_boundary, is_alive); 1713 } 1714 1715 #ifdef ASSERT 1716 1717 class CheckClass : AllStatic { 1718 static BoolObjectClosure* _is_alive; 1719 1720 // Check class_loader is alive for this bit of metadata. 1721 static void check_class(Metadata* md) { 1722 Klass* klass = NULL; 1723 if (md->is_klass()) { 1724 klass = ((Klass*)md); 1725 } else if (md->is_method()) { 1726 klass = ((Method*)md)->method_holder(); 1727 } else if (md->is_methodData()) { 1728 klass = ((MethodData*)md)->method()->method_holder(); 1729 } else { 1730 md->print(); 1731 ShouldNotReachHere(); 1732 } 1733 assert(klass->is_loader_alive(_is_alive), "must be alive"); 1734 } 1735 public: 1736 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) { 1737 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint"); 1738 _is_alive = is_alive; 1739 nm->metadata_do(check_class); 1740 } 1741 }; 1742 1743 // This is called during a safepoint so can use static data 1744 BoolObjectClosure* CheckClass::_is_alive = NULL; 1745 #endif // ASSERT 1746 1747 1748 // Processing of oop references should have been sufficient to keep 1749 // all strong references alive. Any weak references should have been 1750 // cleared as well. Visit all the metadata and ensure that it's 1751 // really alive. 1752 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) { 1753 #ifdef ASSERT 1754 RelocIterator iter(this, low_boundary); 1755 while (iter.next()) { 1756 // static_stub_Relocations may have dangling references to 1757 // Method*s so trim them out here. Otherwise it looks like 1758 // compiled code is maintaining a link to dead metadata. 1759 address static_call_addr = NULL; 1760 if (iter.type() == relocInfo::opt_virtual_call_type) { 1761 CompiledIC* cic = CompiledIC_at(iter.reloc()); 1762 if (!cic->is_call_to_interpreted()) { 1763 static_call_addr = iter.addr(); 1764 } 1765 } else if (iter.type() == relocInfo::static_call_type) { 1766 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc()); 1767 if (!csc->is_call_to_interpreted()) { 1768 static_call_addr = iter.addr(); 1769 } 1770 } 1771 if (static_call_addr != NULL) { 1772 RelocIterator sciter(this, low_boundary); 1773 while (sciter.next()) { 1774 if (sciter.type() == relocInfo::static_stub_type && 1775 sciter.static_stub_reloc()->static_call() == static_call_addr) { 1776 sciter.static_stub_reloc()->clear_inline_cache(); 1777 } 1778 } 1779 } 1780 } 1781 // Check that the metadata embedded in the nmethod is alive 1782 CheckClass::do_check_class(is_alive, this); 1783 #endif 1784 } 1785 1786 1787 // Iterate over metadata calling this function. Used by RedefineClasses 1788 void nmethod::metadata_do(void f(Metadata*)) { 1789 address low_boundary = verified_entry_point(); 1790 if (is_not_entrant()) { 1791 low_boundary += NativeJump::instruction_size; 1792 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1793 // (See comment above.) 1794 } 1795 { 1796 // Visit all immediate references that are embedded in the instruction stream. 1797 RelocIterator iter(this, low_boundary); 1798 while (iter.next()) { 1799 if (iter.type() == relocInfo::metadata_type ) { 1800 metadata_Relocation* r = iter.metadata_reloc(); 1801 // In this lmetadata, we must only follow those metadatas directly embedded in 1802 // the code. Other metadatas (oop_index>0) are seen as part of 1803 // the metadata section below. 1804 assert(1 == (r->metadata_is_immediate()) + 1805 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), 1806 "metadata must be found in exactly one place"); 1807 if (r->metadata_is_immediate() && r->metadata_value() != NULL) { 1808 Metadata* md = r->metadata_value(); 1809 f(md); 1810 } 1811 } else if (iter.type() == relocInfo::virtual_call_type) { 1812 // Check compiledIC holders associated with this nmethod 1813 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1814 if (ic->is_icholder_call()) { 1815 CompiledICHolder* cichk = ic->cached_icholder(); 1816 f(cichk->holder_method()); 1817 f(cichk->holder_klass()); 1818 } else { 1819 Metadata* ic_oop = ic->cached_metadata(); 1820 if (ic_oop != NULL) { 1821 f(ic_oop); 1822 } 1823 } 1824 } 1825 } 1826 } 1827 1828 // Visit the metadata section 1829 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { 1830 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops 1831 Metadata* md = *p; 1832 f(md); 1833 } 1834 1835 // Call function Method*, not embedded in these other places. 1836 if (_method != NULL) f(_method); 1837 } 1838 1839 1840 // This method is called twice during GC -- once while 1841 // tracing the "active" nmethods on thread stacks during 1842 // the (strong) marking phase, and then again when walking 1843 // the code cache contents during the weak roots processing 1844 // phase. The two uses are distinguished by means of the 1845 // 'do_strong_roots_only' flag, which is true in the first 1846 // case. We want to walk the weak roots in the nmethod 1847 // only in the second case. The weak roots in the nmethod 1848 // are the oops in the ExceptionCache and the InlineCache 1849 // oops. 1850 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) { 1851 // make sure the oops ready to receive visitors 1852 assert(NMethodSweeper::is_sweeping(this) || is_marked_for_deoptimization() || 1853 (!is_zombie() && !is_unloaded()), 1854 "should not call follow on zombie or unloaded nmethod"); 1855 1856 // If the method is not entrant or zombie then a JMP is plastered over the 1857 // first few bytes. If an oop in the old code was there, that oop 1858 // should not get GC'd. Skip the first few bytes of oops on 1859 // not-entrant methods. 1860 address low_boundary = verified_entry_point(); 1861 if (is_not_entrant()) { 1862 low_boundary += NativeJump::instruction_size; 1863 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1864 // (See comment above.) 1865 } 1866 1867 RelocIterator iter(this, low_boundary); 1868 1869 while (iter.next()) { 1870 if (iter.type() == relocInfo::oop_type ) { 1871 oop_Relocation* r = iter.oop_reloc(); 1872 // In this loop, we must only follow those oops directly embedded in 1873 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1874 assert(1 == (r->oop_is_immediate()) + 1875 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1876 "oop must be found in exactly one place"); 1877 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1878 f->do_oop(r->oop_addr()); 1879 } 1880 } 1881 } 1882 1883 // Scopes 1884 // This includes oop constants not inlined in the code stream. 1885 for (oop* p = oops_begin(); p < oops_end(); p++) { 1886 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1887 f->do_oop(p); 1888 } 1889 } 1890 1891 #define NMETHOD_SENTINEL ((nmethod*)badAddress) 1892 1893 nmethod* volatile nmethod::_oops_do_mark_nmethods; 1894 1895 // An nmethod is "marked" if its _mark_link is set non-null. 1896 // Even if it is the end of the linked list, it will have a non-null link value, 1897 // as long as it is on the list. 1898 // This code must be MP safe, because it is used from parallel GC passes. 1899 bool nmethod::test_set_oops_do_mark() { 1900 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called"); 1901 nmethod* observed_mark_link = _oops_do_mark_link; 1902 if (observed_mark_link == NULL) { 1903 // Claim this nmethod for this thread to mark. 1904 observed_mark_link = (nmethod*) 1905 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL); 1906 if (observed_mark_link == NULL) { 1907 1908 // Atomically append this nmethod (now claimed) to the head of the list: 1909 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods; 1910 for (;;) { 1911 nmethod* required_mark_nmethods = observed_mark_nmethods; 1912 _oops_do_mark_link = required_mark_nmethods; 1913 observed_mark_nmethods = (nmethod*) 1914 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods); 1915 if (observed_mark_nmethods == required_mark_nmethods) 1916 break; 1917 } 1918 // Mark was clear when we first saw this guy. 1919 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark")); 1920 return false; 1921 } 1922 } 1923 // On fall through, another racing thread marked this nmethod before we did. 1924 return true; 1925 } 1926 1927 void nmethod::oops_do_marking_prologue() { 1928 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue")); 1929 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row"); 1930 // We use cmpxchg_ptr instead of regular assignment here because the user 1931 // may fork a bunch of threads, and we need them all to see the same state. 1932 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL); 1933 guarantee(observed == NULL, "no races in this sequential code"); 1934 } 1935 1936 void nmethod::oops_do_marking_epilogue() { 1937 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row"); 1938 nmethod* cur = _oops_do_mark_nmethods; 1939 while (cur != NMETHOD_SENTINEL) { 1940 assert(cur != NULL, "not NULL-terminated"); 1941 nmethod* next = cur->_oops_do_mark_link; 1942 cur->_oops_do_mark_link = NULL; 1943 cur->fix_oop_relocations(); 1944 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark")); 1945 cur = next; 1946 } 1947 void* required = _oops_do_mark_nmethods; 1948 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required); 1949 guarantee(observed == required, "no races in this sequential code"); 1950 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]")); 1951 } 1952 1953 class DetectScavengeRoot: public OopClosure { 1954 bool _detected_scavenge_root; 1955 public: 1956 DetectScavengeRoot() : _detected_scavenge_root(false) 1957 { NOT_PRODUCT(_print_nm = NULL); } 1958 bool detected_scavenge_root() { return _detected_scavenge_root; } 1959 virtual void do_oop(oop* p) { 1960 if ((*p) != NULL && (*p)->is_scavengable()) { 1961 NOT_PRODUCT(maybe_print(p)); 1962 _detected_scavenge_root = true; 1963 } 1964 } 1965 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 1966 1967 #ifndef PRODUCT 1968 nmethod* _print_nm; 1969 void maybe_print(oop* p) { 1970 if (_print_nm == NULL) return; 1971 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root"); 1972 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")", 1973 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm), 1974 (intptr_t)(*p), (intptr_t)p); 1975 (*p)->print(); 1976 } 1977 #endif //PRODUCT 1978 }; 1979 1980 bool nmethod::detect_scavenge_root_oops() { 1981 DetectScavengeRoot detect_scavenge_root; 1982 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this); 1983 oops_do(&detect_scavenge_root); 1984 return detect_scavenge_root.detected_scavenge_root(); 1985 } 1986 1987 // Method that knows how to preserve outgoing arguments at call. This method must be 1988 // called with a frame corresponding to a Java invoke 1989 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { 1990 #ifndef SHARK 1991 if (!method()->is_native()) { 1992 SimpleScopeDesc ssd(this, fr.pc()); 1993 Bytecode_invoke call(ssd.method(), ssd.bci()); 1994 bool has_receiver = call.has_receiver(); 1995 bool has_appendix = call.has_appendix(); 1996 Symbol* signature = call.signature(); 1997 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f); 1998 } 1999 #endif // !SHARK 2000 } 2001 2002 2003 oop nmethod::embeddedOop_at(u_char* p) { 2004 RelocIterator iter(this, p, p + 1); 2005 while (iter.next()) 2006 if (iter.type() == relocInfo::oop_type) { 2007 return iter.oop_reloc()->oop_value(); 2008 } 2009 return NULL; 2010 } 2011 2012 2013 inline bool includes(void* p, void* from, void* to) { 2014 return from <= p && p < to; 2015 } 2016 2017 2018 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) { 2019 assert(count >= 2, "must be sentinel values, at least"); 2020 2021 #ifdef ASSERT 2022 // must be sorted and unique; we do a binary search in find_pc_desc() 2023 int prev_offset = pcs[0].pc_offset(); 2024 assert(prev_offset == PcDesc::lower_offset_limit, 2025 "must start with a sentinel"); 2026 for (int i = 1; i < count; i++) { 2027 int this_offset = pcs[i].pc_offset(); 2028 assert(this_offset > prev_offset, "offsets must be sorted"); 2029 prev_offset = this_offset; 2030 } 2031 assert(prev_offset == PcDesc::upper_offset_limit, 2032 "must end with a sentinel"); 2033 #endif //ASSERT 2034 2035 // Search for MethodHandle invokes and tag the nmethod. 2036 for (int i = 0; i < count; i++) { 2037 if (pcs[i].is_method_handle_invoke()) { 2038 set_has_method_handle_invokes(true); 2039 break; 2040 } 2041 } 2042 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler"); 2043 2044 int size = count * sizeof(PcDesc); 2045 assert(scopes_pcs_size() >= size, "oob"); 2046 memcpy(scopes_pcs_begin(), pcs, size); 2047 2048 // Adjust the final sentinel downward. 2049 PcDesc* last_pc = &scopes_pcs_begin()[count-1]; 2050 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity"); 2051 last_pc->set_pc_offset(content_size() + 1); 2052 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { 2053 // Fill any rounding gaps with copies of the last record. 2054 last_pc[1] = last_pc[0]; 2055 } 2056 // The following assert could fail if sizeof(PcDesc) is not 2057 // an integral multiple of oopSize (the rounding term). 2058 // If it fails, change the logic to always allocate a multiple 2059 // of sizeof(PcDesc), and fill unused words with copies of *last_pc. 2060 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly"); 2061 } 2062 2063 void nmethod::copy_scopes_data(u_char* buffer, int size) { 2064 assert(scopes_data_size() >= size, "oob"); 2065 memcpy(scopes_data_begin(), buffer, size); 2066 } 2067 2068 2069 #ifdef ASSERT 2070 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) { 2071 PcDesc* lower = nm->scopes_pcs_begin(); 2072 PcDesc* upper = nm->scopes_pcs_end(); 2073 lower += 1; // exclude initial sentinel 2074 PcDesc* res = NULL; 2075 for (PcDesc* p = lower; p < upper; p++) { 2076 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc 2077 if (match_desc(p, pc_offset, approximate)) { 2078 if (res == NULL) 2079 res = p; 2080 else 2081 res = (PcDesc*) badAddress; 2082 } 2083 } 2084 return res; 2085 } 2086 #endif 2087 2088 2089 // Finds a PcDesc with real-pc equal to "pc" 2090 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) { 2091 address base_address = code_begin(); 2092 if ((pc < base_address) || 2093 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { 2094 return NULL; // PC is wildly out of range 2095 } 2096 int pc_offset = (int) (pc - base_address); 2097 2098 // Check the PcDesc cache if it contains the desired PcDesc 2099 // (This as an almost 100% hit rate.) 2100 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); 2101 if (res != NULL) { 2102 assert(res == linear_search(this, pc_offset, approximate), "cache ok"); 2103 return res; 2104 } 2105 2106 // Fallback algorithm: quasi-linear search for the PcDesc 2107 // Find the last pc_offset less than the given offset. 2108 // The successor must be the required match, if there is a match at all. 2109 // (Use a fixed radix to avoid expensive affine pointer arithmetic.) 2110 PcDesc* lower = scopes_pcs_begin(); 2111 PcDesc* upper = scopes_pcs_end(); 2112 upper -= 1; // exclude final sentinel 2113 if (lower >= upper) return NULL; // native method; no PcDescs at all 2114 2115 #define assert_LU_OK \ 2116 /* invariant on lower..upper during the following search: */ \ 2117 assert(lower->pc_offset() < pc_offset, "sanity"); \ 2118 assert(upper->pc_offset() >= pc_offset, "sanity") 2119 assert_LU_OK; 2120 2121 // Use the last successful return as a split point. 2122 PcDesc* mid = _pc_desc_cache.last_pc_desc(); 2123 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2124 if (mid->pc_offset() < pc_offset) { 2125 lower = mid; 2126 } else { 2127 upper = mid; 2128 } 2129 2130 // Take giant steps at first (4096, then 256, then 16, then 1) 2131 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); 2132 const int RADIX = (1 << LOG2_RADIX); 2133 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { 2134 while ((mid = lower + step) < upper) { 2135 assert_LU_OK; 2136 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2137 if (mid->pc_offset() < pc_offset) { 2138 lower = mid; 2139 } else { 2140 upper = mid; 2141 break; 2142 } 2143 } 2144 assert_LU_OK; 2145 } 2146 2147 // Sneak up on the value with a linear search of length ~16. 2148 while (true) { 2149 assert_LU_OK; 2150 mid = lower + 1; 2151 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2152 if (mid->pc_offset() < pc_offset) { 2153 lower = mid; 2154 } else { 2155 upper = mid; 2156 break; 2157 } 2158 } 2159 #undef assert_LU_OK 2160 2161 if (match_desc(upper, pc_offset, approximate)) { 2162 assert(upper == linear_search(this, pc_offset, approximate), "search ok"); 2163 _pc_desc_cache.add_pc_desc(upper); 2164 return upper; 2165 } else { 2166 assert(NULL == linear_search(this, pc_offset, approximate), "search ok"); 2167 return NULL; 2168 } 2169 } 2170 2171 2172 bool nmethod::check_all_dependencies() { 2173 bool found_check = false; 2174 // wholesale check of all dependencies 2175 for (Dependencies::DepStream deps(this); deps.next(); ) { 2176 if (deps.check_dependency() != NULL) { 2177 found_check = true; 2178 NOT_DEBUG(break); 2179 } 2180 } 2181 return found_check; // tell caller if we found anything 2182 } 2183 2184 bool nmethod::check_dependency_on(DepChange& changes) { 2185 // What has happened: 2186 // 1) a new class dependee has been added 2187 // 2) dependee and all its super classes have been marked 2188 bool found_check = false; // set true if we are upset 2189 for (Dependencies::DepStream deps(this); deps.next(); ) { 2190 // Evaluate only relevant dependencies. 2191 if (deps.spot_check_dependency_at(changes) != NULL) { 2192 found_check = true; 2193 NOT_DEBUG(break); 2194 } 2195 } 2196 return found_check; 2197 } 2198 2199 bool nmethod::is_evol_dependent_on(Klass* dependee) { 2200 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee); 2201 Array<Method*>* dependee_methods = dependee_ik->methods(); 2202 for (Dependencies::DepStream deps(this); deps.next(); ) { 2203 if (deps.type() == Dependencies::evol_method) { 2204 Method* method = deps.method_argument(0); 2205 for (int j = 0; j < dependee_methods->length(); j++) { 2206 if (dependee_methods->at(j) == method) { 2207 // RC_TRACE macro has an embedded ResourceMark 2208 RC_TRACE(0x01000000, 2209 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)", 2210 _method->method_holder()->external_name(), 2211 _method->name()->as_C_string(), 2212 _method->signature()->as_C_string(), compile_id(), 2213 method->method_holder()->external_name(), 2214 method->name()->as_C_string(), 2215 method->signature()->as_C_string())); 2216 if (TraceDependencies || LogCompilation) 2217 deps.log_dependency(dependee); 2218 return true; 2219 } 2220 } 2221 } 2222 } 2223 return false; 2224 } 2225 2226 // Called from mark_for_deoptimization, when dependee is invalidated. 2227 bool nmethod::is_dependent_on_method(Method* dependee) { 2228 for (Dependencies::DepStream deps(this); deps.next(); ) { 2229 if (deps.type() != Dependencies::evol_method) 2230 continue; 2231 Method* method = deps.method_argument(0); 2232 if (method == dependee) return true; 2233 } 2234 return false; 2235 } 2236 2237 2238 bool nmethod::is_patchable_at(address instr_addr) { 2239 assert(insts_contains(instr_addr), "wrong nmethod used"); 2240 if (is_zombie()) { 2241 // a zombie may never be patched 2242 return false; 2243 } 2244 return true; 2245 } 2246 2247 2248 address nmethod::continuation_for_implicit_exception(address pc) { 2249 // Exception happened outside inline-cache check code => we are inside 2250 // an active nmethod => use cpc to determine a return address 2251 int exception_offset = pc - code_begin(); 2252 int cont_offset = ImplicitExceptionTable(this).at( exception_offset ); 2253 #ifdef ASSERT 2254 if (cont_offset == 0) { 2255 Thread* thread = ThreadLocalStorage::get_thread_slow(); 2256 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY 2257 HandleMark hm(thread); 2258 ResourceMark rm(thread); 2259 CodeBlob* cb = CodeCache::find_blob(pc); 2260 assert(cb != NULL && cb == this, ""); 2261 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc); 2262 print(); 2263 method()->print_codes(); 2264 print_code(); 2265 print_pcs(); 2266 } 2267 #endif 2268 if (cont_offset == 0) { 2269 // Let the normal error handling report the exception 2270 return NULL; 2271 } 2272 return code_begin() + cont_offset; 2273 } 2274 2275 2276 2277 void nmethod_init() { 2278 // make sure you didn't forget to adjust the filler fields 2279 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word"); 2280 } 2281 2282 2283 //------------------------------------------------------------------------------------------- 2284 2285 2286 // QQQ might we make this work from a frame?? 2287 nmethodLocker::nmethodLocker(address pc) { 2288 CodeBlob* cb = CodeCache::find_blob(pc); 2289 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found"); 2290 _nm = (nmethod*)cb; 2291 lock_nmethod(_nm); 2292 } 2293 2294 // Only JvmtiDeferredEvent::compiled_method_unload_event() 2295 // should pass zombie_ok == true. 2296 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) { 2297 if (nm == NULL) return; 2298 Atomic::inc(&nm->_lock_count); 2299 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method"); 2300 } 2301 2302 void nmethodLocker::unlock_nmethod(nmethod* nm) { 2303 if (nm == NULL) return; 2304 Atomic::dec(&nm->_lock_count); 2305 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock"); 2306 } 2307 2308 2309 // ----------------------------------------------------------------------------- 2310 // nmethod::get_deopt_original_pc 2311 // 2312 // Return the original PC for the given PC if: 2313 // (a) the given PC belongs to a nmethod and 2314 // (b) it is a deopt PC 2315 address nmethod::get_deopt_original_pc(const frame* fr) { 2316 if (fr->cb() == NULL) return NULL; 2317 2318 nmethod* nm = fr->cb()->as_nmethod_or_null(); 2319 if (nm != NULL && nm->is_deopt_pc(fr->pc())) 2320 return nm->get_original_pc(fr); 2321 2322 return NULL; 2323 } 2324 2325 2326 // ----------------------------------------------------------------------------- 2327 // MethodHandle 2328 2329 bool nmethod::is_method_handle_return(address return_pc) { 2330 if (!has_method_handle_invokes()) return false; 2331 PcDesc* pd = pc_desc_at(return_pc); 2332 if (pd == NULL) 2333 return false; 2334 return pd->is_method_handle_invoke(); 2335 } 2336 2337 2338 // ----------------------------------------------------------------------------- 2339 // Verification 2340 2341 class VerifyOopsClosure: public OopClosure { 2342 nmethod* _nm; 2343 bool _ok; 2344 public: 2345 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } 2346 bool ok() { return _ok; } 2347 virtual void do_oop(oop* p) { 2348 if ((*p) == NULL || (*p)->is_oop()) return; 2349 if (_ok) { 2350 _nm->print_nmethod(true); 2351 _ok = false; 2352 } 2353 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2354 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2355 } 2356 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2357 }; 2358 2359 void nmethod::verify() { 2360 2361 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant 2362 // seems odd. 2363 2364 if( is_zombie() || is_not_entrant() ) 2365 return; 2366 2367 // Make sure all the entry points are correctly aligned for patching. 2368 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point()); 2369 2370 // assert(method()->is_oop(), "must be valid"); 2371 2372 ResourceMark rm; 2373 2374 if (!CodeCache::contains(this)) { 2375 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this)); 2376 } 2377 2378 if(is_native_method() ) 2379 return; 2380 2381 nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); 2382 if (nm != this) { 2383 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", 2384 this)); 2385 } 2386 2387 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2388 if (! p->verify(this)) { 2389 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this); 2390 } 2391 } 2392 2393 VerifyOopsClosure voc(this); 2394 oops_do(&voc); 2395 assert(voc.ok(), "embedded oops must be OK"); 2396 verify_scavenge_root_oops(); 2397 2398 verify_scopes(); 2399 } 2400 2401 2402 void nmethod::verify_interrupt_point(address call_site) { 2403 // This code does not work in release mode since 2404 // owns_lock only is available in debug mode. 2405 CompiledIC* ic = NULL; 2406 Thread *cur = Thread::current(); 2407 if (CompiledIC_lock->owner() == cur || 2408 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) && 2409 SafepointSynchronize::is_at_safepoint())) { 2410 ic = CompiledIC_at(this, call_site); 2411 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 2412 } else { 2413 MutexLocker ml_verify (CompiledIC_lock); 2414 ic = CompiledIC_at(this, call_site); 2415 } 2416 PcDesc* pd = pc_desc_at(ic->end_of_call()); 2417 assert(pd != NULL, "PcDesc must exist"); 2418 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(), 2419 pd->obj_decode_offset(), pd->should_reexecute(), 2420 pd->return_oop()); 2421 !sd->is_top(); sd = sd->sender()) { 2422 sd->verify(); 2423 } 2424 } 2425 2426 void nmethod::verify_scopes() { 2427 if( !method() ) return; // Runtime stubs have no scope 2428 if (method()->is_native()) return; // Ignore stub methods. 2429 // iterate through all interrupt point 2430 // and verify the debug information is valid. 2431 RelocIterator iter((nmethod*)this); 2432 while (iter.next()) { 2433 address stub = NULL; 2434 switch (iter.type()) { 2435 case relocInfo::virtual_call_type: 2436 verify_interrupt_point(iter.addr()); 2437 break; 2438 case relocInfo::opt_virtual_call_type: 2439 stub = iter.opt_virtual_call_reloc()->static_stub(); 2440 verify_interrupt_point(iter.addr()); 2441 break; 2442 case relocInfo::static_call_type: 2443 stub = iter.static_call_reloc()->static_stub(); 2444 //verify_interrupt_point(iter.addr()); 2445 break; 2446 case relocInfo::runtime_call_type: 2447 address destination = iter.reloc()->value(); 2448 // Right now there is no way to find out which entries support 2449 // an interrupt point. It would be nice if we had this 2450 // information in a table. 2451 break; 2452 } 2453 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section"); 2454 } 2455 } 2456 2457 2458 // ----------------------------------------------------------------------------- 2459 // Non-product code 2460 #ifndef PRODUCT 2461 2462 class DebugScavengeRoot: public OopClosure { 2463 nmethod* _nm; 2464 bool _ok; 2465 public: 2466 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { } 2467 bool ok() { return _ok; } 2468 virtual void do_oop(oop* p) { 2469 if ((*p) == NULL || !(*p)->is_scavengable()) return; 2470 if (_ok) { 2471 _nm->print_nmethod(true); 2472 _ok = false; 2473 } 2474 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2475 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2476 (*p)->print(); 2477 } 2478 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2479 }; 2480 2481 void nmethod::verify_scavenge_root_oops() { 2482 if (!on_scavenge_root_list()) { 2483 // Actually look inside, to verify the claim that it's clean. 2484 DebugScavengeRoot debug_scavenge_root(this); 2485 oops_do(&debug_scavenge_root); 2486 if (!debug_scavenge_root.ok()) 2487 fatal("found an unadvertised bad scavengable oop in the code cache"); 2488 } 2489 assert(scavenge_root_not_marked(), ""); 2490 } 2491 2492 #endif // PRODUCT 2493 2494 // Printing operations 2495 2496 void nmethod::print() const { 2497 ResourceMark rm; 2498 ttyLocker ttyl; // keep the following output all in one block 2499 2500 tty->print("Compiled method "); 2501 2502 if (is_compiled_by_c1()) { 2503 tty->print("(c1) "); 2504 } else if (is_compiled_by_c2()) { 2505 tty->print("(c2) "); 2506 } else if (is_compiled_by_shark()) { 2507 tty->print("(shark) "); 2508 } else { 2509 tty->print("(nm) "); 2510 } 2511 2512 print_on(tty, NULL); 2513 2514 if (WizardMode) { 2515 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this); 2516 tty->print(" for method " INTPTR_FORMAT , (address)method()); 2517 tty->print(" { "); 2518 if (is_in_use()) tty->print("in_use "); 2519 if (is_not_entrant()) tty->print("not_entrant "); 2520 if (is_zombie()) tty->print("zombie "); 2521 if (is_unloaded()) tty->print("unloaded "); 2522 if (on_scavenge_root_list()) tty->print("scavenge_root "); 2523 tty->print_cr("}:"); 2524 } 2525 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2526 (address)this, 2527 (address)this + size(), 2528 size()); 2529 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2530 relocation_begin(), 2531 relocation_end(), 2532 relocation_size()); 2533 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2534 consts_begin(), 2535 consts_end(), 2536 consts_size()); 2537 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2538 insts_begin(), 2539 insts_end(), 2540 insts_size()); 2541 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2542 stub_begin(), 2543 stub_end(), 2544 stub_size()); 2545 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2546 oops_begin(), 2547 oops_end(), 2548 oops_size()); 2549 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2550 metadata_begin(), 2551 metadata_end(), 2552 metadata_size()); 2553 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2554 scopes_data_begin(), 2555 scopes_data_end(), 2556 scopes_data_size()); 2557 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2558 scopes_pcs_begin(), 2559 scopes_pcs_end(), 2560 scopes_pcs_size()); 2561 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2562 dependencies_begin(), 2563 dependencies_end(), 2564 dependencies_size()); 2565 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2566 handler_table_begin(), 2567 handler_table_end(), 2568 handler_table_size()); 2569 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2570 nul_chk_table_begin(), 2571 nul_chk_table_end(), 2572 nul_chk_table_size()); 2573 } 2574 2575 void nmethod::print_code() { 2576 HandleMark hm; 2577 ResourceMark m; 2578 Disassembler::decode(this); 2579 } 2580 2581 2582 #ifndef PRODUCT 2583 2584 void nmethod::print_scopes() { 2585 // Find the first pc desc for all scopes in the code and print it. 2586 ResourceMark rm; 2587 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2588 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) 2589 continue; 2590 2591 ScopeDesc* sd = scope_desc_at(p->real_pc(this)); 2592 sd->print_on(tty, p); 2593 } 2594 } 2595 2596 void nmethod::print_dependencies() { 2597 ResourceMark rm; 2598 ttyLocker ttyl; // keep the following output all in one block 2599 tty->print_cr("Dependencies:"); 2600 for (Dependencies::DepStream deps(this); deps.next(); ) { 2601 deps.print_dependency(); 2602 Klass* ctxk = deps.context_type(); 2603 if (ctxk != NULL) { 2604 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) { 2605 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name()); 2606 } 2607 } 2608 deps.log_dependency(); // put it into the xml log also 2609 } 2610 } 2611 2612 2613 void nmethod::print_relocations() { 2614 ResourceMark m; // in case methods get printed via the debugger 2615 tty->print_cr("relocations:"); 2616 RelocIterator iter(this); 2617 iter.print(); 2618 if (UseRelocIndex) { 2619 jint* index_end = (jint*)relocation_end() - 1; 2620 jint index_size = *index_end; 2621 jint* index_start = (jint*)( (address)index_end - index_size ); 2622 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size); 2623 if (index_size > 0) { 2624 jint* ip; 2625 for (ip = index_start; ip+2 <= index_end; ip += 2) 2626 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT, 2627 ip[0], 2628 ip[1], 2629 header_end()+ip[0], 2630 relocation_begin()-1+ip[1]); 2631 for (; ip < index_end; ip++) 2632 tty->print_cr(" (%d ?)", ip[0]); 2633 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip); 2634 ip++; 2635 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip); 2636 } 2637 } 2638 } 2639 2640 2641 void nmethod::print_pcs() { 2642 ResourceMark m; // in case methods get printed via debugger 2643 tty->print_cr("pc-bytecode offsets:"); 2644 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2645 p->print(this); 2646 } 2647 } 2648 2649 #endif // PRODUCT 2650 2651 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) { 2652 RelocIterator iter(this, begin, end); 2653 bool have_one = false; 2654 while (iter.next()) { 2655 have_one = true; 2656 switch (iter.type()) { 2657 case relocInfo::none: return "no_reloc"; 2658 case relocInfo::oop_type: { 2659 stringStream st; 2660 oop_Relocation* r = iter.oop_reloc(); 2661 oop obj = r->oop_value(); 2662 st.print("oop("); 2663 if (obj == NULL) st.print("NULL"); 2664 else obj->print_value_on(&st); 2665 st.print(")"); 2666 return st.as_string(); 2667 } 2668 case relocInfo::metadata_type: { 2669 stringStream st; 2670 metadata_Relocation* r = iter.metadata_reloc(); 2671 Metadata* obj = r->metadata_value(); 2672 st.print("metadata("); 2673 if (obj == NULL) st.print("NULL"); 2674 else obj->print_value_on(&st); 2675 st.print(")"); 2676 return st.as_string(); 2677 } 2678 case relocInfo::virtual_call_type: return "virtual_call"; 2679 case relocInfo::opt_virtual_call_type: return "optimized virtual_call"; 2680 case relocInfo::static_call_type: return "static_call"; 2681 case relocInfo::static_stub_type: return "static_stub"; 2682 case relocInfo::runtime_call_type: return "runtime_call"; 2683 case relocInfo::external_word_type: return "external_word"; 2684 case relocInfo::internal_word_type: return "internal_word"; 2685 case relocInfo::section_word_type: return "section_word"; 2686 case relocInfo::poll_type: return "poll"; 2687 case relocInfo::poll_return_type: return "poll_return"; 2688 case relocInfo::type_mask: return "type_bit_mask"; 2689 } 2690 } 2691 return have_one ? "other" : NULL; 2692 } 2693 2694 // Return a the last scope in (begin..end] 2695 ScopeDesc* nmethod::scope_desc_in(address begin, address end) { 2696 PcDesc* p = pc_desc_near(begin+1); 2697 if (p != NULL && p->real_pc(this) <= end) { 2698 return new ScopeDesc(this, p->scope_decode_offset(), 2699 p->obj_decode_offset(), p->should_reexecute(), 2700 p->return_oop()); 2701 } 2702 return NULL; 2703 } 2704 2705 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const { 2706 if (block_begin == entry_point()) stream->print_cr("[Entry Point]"); 2707 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]"); 2708 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]"); 2709 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]"); 2710 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]"); 2711 2712 if (has_method_handle_invokes()) 2713 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]"); 2714 2715 if (block_begin == consts_begin()) stream->print_cr("[Constants]"); 2716 2717 if (block_begin == entry_point()) { 2718 methodHandle m = method(); 2719 if (m.not_null()) { 2720 stream->print(" # "); 2721 m->print_value_on(stream); 2722 stream->cr(); 2723 } 2724 if (m.not_null() && !is_osr_method()) { 2725 ResourceMark rm; 2726 int sizeargs = m->size_of_parameters(); 2727 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs); 2728 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs); 2729 { 2730 int sig_index = 0; 2731 if (!m->is_static()) 2732 sig_bt[sig_index++] = T_OBJECT; // 'this' 2733 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) { 2734 BasicType t = ss.type(); 2735 sig_bt[sig_index++] = t; 2736 if (type2size[t] == 2) { 2737 sig_bt[sig_index++] = T_VOID; 2738 } else { 2739 assert(type2size[t] == 1, "size is 1 or 2"); 2740 } 2741 } 2742 assert(sig_index == sizeargs, ""); 2743 } 2744 const char* spname = "sp"; // make arch-specific? 2745 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false); 2746 int stack_slot_offset = this->frame_size() * wordSize; 2747 int tab1 = 14, tab2 = 24; 2748 int sig_index = 0; 2749 int arg_index = (m->is_static() ? 0 : -1); 2750 bool did_old_sp = false; 2751 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) { 2752 bool at_this = (arg_index == -1); 2753 bool at_old_sp = false; 2754 BasicType t = (at_this ? T_OBJECT : ss.type()); 2755 assert(t == sig_bt[sig_index], "sigs in sync"); 2756 if (at_this) 2757 stream->print(" # this: "); 2758 else 2759 stream->print(" # parm%d: ", arg_index); 2760 stream->move_to(tab1); 2761 VMReg fst = regs[sig_index].first(); 2762 VMReg snd = regs[sig_index].second(); 2763 if (fst->is_reg()) { 2764 stream->print("%s", fst->name()); 2765 if (snd->is_valid()) { 2766 stream->print(":%s", snd->name()); 2767 } 2768 } else if (fst->is_stack()) { 2769 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset; 2770 if (offset == stack_slot_offset) at_old_sp = true; 2771 stream->print("[%s+0x%x]", spname, offset); 2772 } else { 2773 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd); 2774 } 2775 stream->print(" "); 2776 stream->move_to(tab2); 2777 stream->print("= "); 2778 if (at_this) { 2779 m->method_holder()->print_value_on(stream); 2780 } else { 2781 bool did_name = false; 2782 if (!at_this && ss.is_object()) { 2783 Symbol* name = ss.as_symbol_or_null(); 2784 if (name != NULL) { 2785 name->print_value_on(stream); 2786 did_name = true; 2787 } 2788 } 2789 if (!did_name) 2790 stream->print("%s", type2name(t)); 2791 } 2792 if (at_old_sp) { 2793 stream->print(" (%s of caller)", spname); 2794 did_old_sp = true; 2795 } 2796 stream->cr(); 2797 sig_index += type2size[t]; 2798 arg_index += 1; 2799 if (!at_this) ss.next(); 2800 } 2801 if (!did_old_sp) { 2802 stream->print(" # "); 2803 stream->move_to(tab1); 2804 stream->print("[%s+0x%x]", spname, stack_slot_offset); 2805 stream->print(" (%s of caller)", spname); 2806 stream->cr(); 2807 } 2808 } 2809 } 2810 } 2811 2812 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) { 2813 // First, find an oopmap in (begin, end]. 2814 // We use the odd half-closed interval so that oop maps and scope descs 2815 // which are tied to the byte after a call are printed with the call itself. 2816 address base = code_begin(); 2817 OopMapSet* oms = oop_maps(); 2818 if (oms != NULL) { 2819 for (int i = 0, imax = oms->size(); i < imax; i++) { 2820 OopMap* om = oms->at(i); 2821 address pc = base + om->offset(); 2822 if (pc > begin) { 2823 if (pc <= end) { 2824 st->move_to(column); 2825 st->print("; "); 2826 om->print_on(st); 2827 } 2828 break; 2829 } 2830 } 2831 } 2832 2833 // Print any debug info present at this pc. 2834 ScopeDesc* sd = scope_desc_in(begin, end); 2835 if (sd != NULL) { 2836 st->move_to(column); 2837 if (sd->bci() == SynchronizationEntryBCI) { 2838 st->print(";*synchronization entry"); 2839 } else { 2840 if (sd->method() == NULL) { 2841 st->print("method is NULL"); 2842 } else if (sd->method()->is_native()) { 2843 st->print("method is native"); 2844 } else { 2845 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci()); 2846 st->print(";*%s", Bytecodes::name(bc)); 2847 switch (bc) { 2848 case Bytecodes::_invokevirtual: 2849 case Bytecodes::_invokespecial: 2850 case Bytecodes::_invokestatic: 2851 case Bytecodes::_invokeinterface: 2852 { 2853 Bytecode_invoke invoke(sd->method(), sd->bci()); 2854 st->print(" "); 2855 if (invoke.name() != NULL) 2856 invoke.name()->print_symbol_on(st); 2857 else 2858 st->print("<UNKNOWN>"); 2859 break; 2860 } 2861 case Bytecodes::_getfield: 2862 case Bytecodes::_putfield: 2863 case Bytecodes::_getstatic: 2864 case Bytecodes::_putstatic: 2865 { 2866 Bytecode_field field(sd->method(), sd->bci()); 2867 st->print(" "); 2868 if (field.name() != NULL) 2869 field.name()->print_symbol_on(st); 2870 else 2871 st->print("<UNKNOWN>"); 2872 } 2873 } 2874 } 2875 } 2876 2877 // Print all scopes 2878 for (;sd != NULL; sd = sd->sender()) { 2879 st->move_to(column); 2880 st->print("; -"); 2881 if (sd->method() == NULL) { 2882 st->print("method is NULL"); 2883 } else { 2884 sd->method()->print_short_name(st); 2885 } 2886 int lineno = sd->method()->line_number_from_bci(sd->bci()); 2887 if (lineno != -1) { 2888 st->print("@%d (line %d)", sd->bci(), lineno); 2889 } else { 2890 st->print("@%d", sd->bci()); 2891 } 2892 st->cr(); 2893 } 2894 } 2895 2896 // Print relocation information 2897 const char* str = reloc_string_for(begin, end); 2898 if (str != NULL) { 2899 if (sd != NULL) st->cr(); 2900 st->move_to(column); 2901 st->print("; {%s}", str); 2902 } 2903 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin()); 2904 if (cont_offset != 0) { 2905 st->move_to(column); 2906 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset); 2907 } 2908 2909 } 2910 2911 #ifndef PRODUCT 2912 2913 void nmethod::print_value_on(outputStream* st) const { 2914 st->print("nmethod"); 2915 print_on(st, NULL); 2916 } 2917 2918 void nmethod::print_calls(outputStream* st) { 2919 RelocIterator iter(this); 2920 while (iter.next()) { 2921 switch (iter.type()) { 2922 case relocInfo::virtual_call_type: 2923 case relocInfo::opt_virtual_call_type: { 2924 VerifyMutexLocker mc(CompiledIC_lock); 2925 CompiledIC_at(iter.reloc())->print(); 2926 break; 2927 } 2928 case relocInfo::static_call_type: 2929 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr()); 2930 compiledStaticCall_at(iter.reloc())->print(); 2931 break; 2932 } 2933 } 2934 } 2935 2936 void nmethod::print_handler_table() { 2937 ExceptionHandlerTable(this).print(); 2938 } 2939 2940 void nmethod::print_nul_chk_table() { 2941 ImplicitExceptionTable(this).print(code_begin()); 2942 } 2943 2944 void nmethod::print_statistics() { 2945 ttyLocker ttyl; 2946 if (xtty != NULL) xtty->head("statistics type='nmethod'"); 2947 nmethod_stats.print_native_nmethod_stats(); 2948 nmethod_stats.print_nmethod_stats(); 2949 DebugInformationRecorder::print_statistics(); 2950 nmethod_stats.print_pc_stats(); 2951 Dependencies::print_statistics(); 2952 if (xtty != NULL) xtty->tail("statistics"); 2953 } 2954 2955 #endif // PRODUCT