1 /* 2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "code/codeCache.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/dependencies.hpp" 29 #include "code/nmethod.hpp" 30 #include "code/scopeDesc.hpp" 31 #include "compiler/abstractCompiler.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "compiler/compileLog.hpp" 34 #include "compiler/compilerOracle.hpp" 35 #include "compiler/disassembler.hpp" 36 #include "interpreter/bytecode.hpp" 37 #include "oops/methodData.hpp" 38 #include "prims/jvmtiRedefineClassesTrace.hpp" 39 #include "prims/jvmtiImpl.hpp" 40 #include "runtime/sharedRuntime.hpp" 41 #include "runtime/sweeper.hpp" 42 #include "utilities/dtrace.hpp" 43 #include "utilities/events.hpp" 44 #include "utilities/xmlstream.hpp" 45 #ifdef SHARK 46 #include "shark/sharkCompiler.hpp" 47 #endif 48 49 #ifdef DTRACE_ENABLED 50 51 // Only bother with this argument setup if dtrace is available 52 53 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 54 { \ 55 Method* m = (method); \ 56 if (m != NULL) { \ 57 Symbol* klass_name = m->klass_name(); \ 58 Symbol* name = m->name(); \ 59 Symbol* signature = m->signature(); \ 60 HOTSPOT_COMPILED_METHOD_UNLOAD( \ 61 (char *) klass_name->bytes(), klass_name->utf8_length(), \ 62 (char *) name->bytes(), name->utf8_length(), \ 63 (char *) signature->bytes(), signature->utf8_length()); \ 64 } \ 65 } 66 67 #else // ndef DTRACE_ENABLED 68 69 #define DTRACE_METHOD_UNLOAD_PROBE(method) 70 71 #endif 72 73 bool nmethod::is_compiled_by_c1() const { 74 if (compiler() == NULL) { 75 return false; 76 } 77 return compiler()->is_c1(); 78 } 79 bool nmethod::is_compiled_by_c2() const { 80 if (compiler() == NULL) { 81 return false; 82 } 83 return compiler()->is_c2(); 84 } 85 bool nmethod::is_compiled_by_shark() const { 86 if (compiler() == NULL) { 87 return false; 88 } 89 return compiler()->is_shark(); 90 } 91 92 93 94 //--------------------------------------------------------------------------------- 95 // NMethod statistics 96 // They are printed under various flags, including: 97 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation. 98 // (In the latter two cases, they like other stats are printed to the log only.) 99 100 #ifndef PRODUCT 101 // These variables are put into one block to reduce relocations 102 // and make it simpler to print from the debugger. 103 static 104 struct nmethod_stats_struct { 105 int nmethod_count; 106 int total_size; 107 int relocation_size; 108 int consts_size; 109 int insts_size; 110 int stub_size; 111 int scopes_data_size; 112 int scopes_pcs_size; 113 int dependencies_size; 114 int handler_table_size; 115 int nul_chk_table_size; 116 int oops_size; 117 118 void note_nmethod(nmethod* nm) { 119 nmethod_count += 1; 120 total_size += nm->size(); 121 relocation_size += nm->relocation_size(); 122 consts_size += nm->consts_size(); 123 insts_size += nm->insts_size(); 124 stub_size += nm->stub_size(); 125 oops_size += nm->oops_size(); 126 scopes_data_size += nm->scopes_data_size(); 127 scopes_pcs_size += nm->scopes_pcs_size(); 128 dependencies_size += nm->dependencies_size(); 129 handler_table_size += nm->handler_table_size(); 130 nul_chk_table_size += nm->nul_chk_table_size(); 131 } 132 void print_nmethod_stats() { 133 if (nmethod_count == 0) return; 134 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count); 135 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size); 136 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size); 137 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size); 138 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size); 139 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size); 140 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size); 141 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size); 142 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size); 143 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size); 144 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size); 145 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size); 146 } 147 148 int native_nmethod_count; 149 int native_total_size; 150 int native_relocation_size; 151 int native_insts_size; 152 int native_oops_size; 153 void note_native_nmethod(nmethod* nm) { 154 native_nmethod_count += 1; 155 native_total_size += nm->size(); 156 native_relocation_size += nm->relocation_size(); 157 native_insts_size += nm->insts_size(); 158 native_oops_size += nm->oops_size(); 159 } 160 void print_native_nmethod_stats() { 161 if (native_nmethod_count == 0) return; 162 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count); 163 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size); 164 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size); 165 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size); 166 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size); 167 } 168 169 int pc_desc_resets; // number of resets (= number of caches) 170 int pc_desc_queries; // queries to nmethod::find_pc_desc 171 int pc_desc_approx; // number of those which have approximate true 172 int pc_desc_repeats; // number of _pc_descs[0] hits 173 int pc_desc_hits; // number of LRU cache hits 174 int pc_desc_tests; // total number of PcDesc examinations 175 int pc_desc_searches; // total number of quasi-binary search steps 176 int pc_desc_adds; // number of LUR cache insertions 177 178 void print_pc_stats() { 179 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query", 180 pc_desc_queries, 181 (double)(pc_desc_tests + pc_desc_searches) 182 / pc_desc_queries); 183 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d", 184 pc_desc_resets, 185 pc_desc_queries, pc_desc_approx, 186 pc_desc_repeats, pc_desc_hits, 187 pc_desc_tests, pc_desc_searches, pc_desc_adds); 188 } 189 } nmethod_stats; 190 #endif //PRODUCT 191 192 193 //--------------------------------------------------------------------------------- 194 195 196 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) { 197 assert(pc != NULL, "Must be non null"); 198 assert(exception.not_null(), "Must be non null"); 199 assert(handler != NULL, "Must be non null"); 200 201 _count = 0; 202 _exception_type = exception->klass(); 203 _next = NULL; 204 205 add_address_and_handler(pc,handler); 206 } 207 208 209 address ExceptionCache::match(Handle exception, address pc) { 210 assert(pc != NULL,"Must be non null"); 211 assert(exception.not_null(),"Must be non null"); 212 if (exception->klass() == exception_type()) { 213 return (test_address(pc)); 214 } 215 216 return NULL; 217 } 218 219 220 bool ExceptionCache::match_exception_with_space(Handle exception) { 221 assert(exception.not_null(),"Must be non null"); 222 if (exception->klass() == exception_type() && count() < cache_size) { 223 return true; 224 } 225 return false; 226 } 227 228 229 address ExceptionCache::test_address(address addr) { 230 for (int i=0; i<count(); i++) { 231 if (pc_at(i) == addr) { 232 return handler_at(i); 233 } 234 } 235 return NULL; 236 } 237 238 239 bool ExceptionCache::add_address_and_handler(address addr, address handler) { 240 if (test_address(addr) == handler) return true; 241 if (count() < cache_size) { 242 set_pc_at(count(),addr); 243 set_handler_at(count(), handler); 244 increment_count(); 245 return true; 246 } 247 return false; 248 } 249 250 251 // private method for handling exception cache 252 // These methods are private, and used to manipulate the exception cache 253 // directly. 254 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) { 255 ExceptionCache* ec = exception_cache(); 256 while (ec != NULL) { 257 if (ec->match_exception_with_space(exception)) { 258 return ec; 259 } 260 ec = ec->next(); 261 } 262 return NULL; 263 } 264 265 266 //----------------------------------------------------------------------------- 267 268 269 // Helper used by both find_pc_desc methods. 270 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) { 271 NOT_PRODUCT(++nmethod_stats.pc_desc_tests); 272 if (!approximate) 273 return pc->pc_offset() == pc_offset; 274 else 275 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset(); 276 } 277 278 void PcDescCache::reset_to(PcDesc* initial_pc_desc) { 279 if (initial_pc_desc == NULL) { 280 _pc_descs[0] = NULL; // native method; no PcDescs at all 281 return; 282 } 283 NOT_PRODUCT(++nmethod_stats.pc_desc_resets); 284 // reset the cache by filling it with benign (non-null) values 285 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel"); 286 for (int i = 0; i < cache_size; i++) 287 _pc_descs[i] = initial_pc_desc; 288 } 289 290 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) { 291 NOT_PRODUCT(++nmethod_stats.pc_desc_queries); 292 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx); 293 294 // Note: one might think that caching the most recently 295 // read value separately would be a win, but one would be 296 // wrong. When many threads are updating it, the cache 297 // line it's in would bounce between caches, negating 298 // any benefit. 299 300 // In order to prevent race conditions do not load cache elements 301 // repeatedly, but use a local copy: 302 PcDesc* res; 303 304 // Step one: Check the most recently added value. 305 res = _pc_descs[0]; 306 if (res == NULL) return NULL; // native method; no PcDescs at all 307 if (match_desc(res, pc_offset, approximate)) { 308 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats); 309 return res; 310 } 311 312 // Step two: Check the rest of the LRU cache. 313 for (int i = 1; i < cache_size; ++i) { 314 res = _pc_descs[i]; 315 if (res->pc_offset() < 0) break; // optimization: skip empty cache 316 if (match_desc(res, pc_offset, approximate)) { 317 NOT_PRODUCT(++nmethod_stats.pc_desc_hits); 318 return res; 319 } 320 } 321 322 // Report failure. 323 return NULL; 324 } 325 326 void PcDescCache::add_pc_desc(PcDesc* pc_desc) { 327 NOT_PRODUCT(++nmethod_stats.pc_desc_adds); 328 // Update the LRU cache by shifting pc_desc forward. 329 for (int i = 0; i < cache_size; i++) { 330 PcDesc* next = _pc_descs[i]; 331 _pc_descs[i] = pc_desc; 332 pc_desc = next; 333 } 334 } 335 336 // adjust pcs_size so that it is a multiple of both oopSize and 337 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple 338 // of oopSize, then 2*sizeof(PcDesc) is) 339 static int adjust_pcs_size(int pcs_size) { 340 int nsize = round_to(pcs_size, oopSize); 341 if ((nsize % sizeof(PcDesc)) != 0) { 342 nsize = pcs_size + sizeof(PcDesc); 343 } 344 assert((nsize % oopSize) == 0, "correct alignment"); 345 return nsize; 346 } 347 348 //----------------------------------------------------------------------------- 349 350 351 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) { 352 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock"); 353 assert(new_entry != NULL,"Must be non null"); 354 assert(new_entry->next() == NULL, "Must be null"); 355 356 if (exception_cache() != NULL) { 357 new_entry->set_next(exception_cache()); 358 } 359 set_exception_cache(new_entry); 360 } 361 362 void nmethod::remove_from_exception_cache(ExceptionCache* ec) { 363 ExceptionCache* prev = NULL; 364 ExceptionCache* curr = exception_cache(); 365 assert(curr != NULL, "nothing to remove"); 366 // find the previous and next entry of ec 367 while (curr != ec) { 368 prev = curr; 369 curr = curr->next(); 370 assert(curr != NULL, "ExceptionCache not found"); 371 } 372 // now: curr == ec 373 ExceptionCache* next = curr->next(); 374 if (prev == NULL) { 375 set_exception_cache(next); 376 } else { 377 prev->set_next(next); 378 } 379 delete curr; 380 } 381 382 383 // public method for accessing the exception cache 384 // These are the public access methods. 385 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) { 386 // We never grab a lock to read the exception cache, so we may 387 // have false negatives. This is okay, as it can only happen during 388 // the first few exception lookups for a given nmethod. 389 ExceptionCache* ec = exception_cache(); 390 while (ec != NULL) { 391 address ret_val; 392 if ((ret_val = ec->match(exception,pc)) != NULL) { 393 return ret_val; 394 } 395 ec = ec->next(); 396 } 397 return NULL; 398 } 399 400 401 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) { 402 // There are potential race conditions during exception cache updates, so we 403 // must own the ExceptionCache_lock before doing ANY modifications. Because 404 // we don't lock during reads, it is possible to have several threads attempt 405 // to update the cache with the same data. We need to check for already inserted 406 // copies of the current data before adding it. 407 408 MutexLocker ml(ExceptionCache_lock); 409 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception); 410 411 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) { 412 target_entry = new ExceptionCache(exception,pc,handler); 413 add_exception_cache_entry(target_entry); 414 } 415 } 416 417 418 //-------------end of code for ExceptionCache-------------- 419 420 421 int nmethod::total_size() const { 422 return 423 consts_size() + 424 insts_size() + 425 stub_size() + 426 scopes_data_size() + 427 scopes_pcs_size() + 428 handler_table_size() + 429 nul_chk_table_size(); 430 } 431 432 const char* nmethod::compile_kind() const { 433 if (is_osr_method()) return "osr"; 434 if (method() != NULL && is_native_method()) return "c2n"; 435 return NULL; 436 } 437 438 // Fill in default values for various flag fields 439 void nmethod::init_defaults() { 440 _state = in_use; 441 _marked_for_reclamation = 0; 442 _has_flushed_dependencies = 0; 443 _has_unsafe_access = 0; 444 _has_method_handle_invokes = 0; 445 _lazy_critical_native = 0; 446 _has_wide_vectors = 0; 447 _marked_for_deoptimization = 0; 448 _lock_count = 0; 449 _stack_traversal_mark = 0; 450 _unload_reported = false; // jvmti state 451 452 #ifdef ASSERT 453 _oops_are_stale = false; 454 #endif 455 456 _oops_do_mark_link = NULL; 457 _jmethod_id = NULL; 458 _osr_link = NULL; 459 _scavenge_root_link = NULL; 460 _scavenge_root_state = 0; 461 _compiler = NULL; 462 463 #ifdef HAVE_DTRACE_H 464 _trap_offset = 0; 465 #endif // def HAVE_DTRACE_H 466 } 467 468 nmethod* nmethod::new_native_nmethod(methodHandle method, 469 int compile_id, 470 CodeBuffer *code_buffer, 471 int vep_offset, 472 int frame_complete, 473 int frame_size, 474 ByteSize basic_lock_owner_sp_offset, 475 ByteSize basic_lock_sp_offset, 476 OopMapSet* oop_maps) { 477 code_buffer->finalize_oop_references(method); 478 // create nmethod 479 nmethod* nm = NULL; 480 { 481 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 482 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 483 CodeOffsets offsets; 484 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 485 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 486 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size, 487 compile_id, &offsets, 488 code_buffer, frame_size, 489 basic_lock_owner_sp_offset, 490 basic_lock_sp_offset, oop_maps); 491 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm)); 492 if (PrintAssembly && nm != NULL) { 493 Disassembler::decode(nm); 494 } 495 } 496 // verify nmethod 497 debug_only(if (nm) nm->verify();) // might block 498 499 if (nm != NULL) { 500 nm->log_new_nmethod(); 501 } 502 503 return nm; 504 } 505 506 #ifdef HAVE_DTRACE_H 507 nmethod* nmethod::new_dtrace_nmethod(methodHandle method, 508 CodeBuffer *code_buffer, 509 int vep_offset, 510 int trap_offset, 511 int frame_complete, 512 int frame_size) { 513 code_buffer->finalize_oop_references(method); 514 // create nmethod 515 nmethod* nm = NULL; 516 { 517 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 518 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 519 CodeOffsets offsets; 520 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 521 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset); 522 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 523 524 nm = new (nmethod_size) nmethod(method(), nmethod_size, 525 &offsets, code_buffer, frame_size); 526 527 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); 528 if (PrintAssembly && nm != NULL) { 529 Disassembler::decode(nm); 530 } 531 } 532 // verify nmethod 533 debug_only(if (nm) nm->verify();) // might block 534 535 if (nm != NULL) { 536 nm->log_new_nmethod(); 537 } 538 539 return nm; 540 } 541 542 #endif // def HAVE_DTRACE_H 543 544 nmethod* nmethod::new_nmethod(methodHandle method, 545 int compile_id, 546 int entry_bci, 547 CodeOffsets* offsets, 548 int orig_pc_offset, 549 DebugInformationRecorder* debug_info, 550 Dependencies* dependencies, 551 CodeBuffer* code_buffer, int frame_size, 552 OopMapSet* oop_maps, 553 ExceptionHandlerTable* handler_table, 554 ImplicitExceptionTable* nul_chk_table, 555 AbstractCompiler* compiler, 556 int comp_level 557 ) 558 { 559 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 560 code_buffer->finalize_oop_references(method); 561 // create nmethod 562 nmethod* nm = NULL; 563 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 564 int nmethod_size = 565 allocation_size(code_buffer, sizeof(nmethod)) 566 + adjust_pcs_size(debug_info->pcs_size()) 567 + round_to(dependencies->size_in_bytes() , oopSize) 568 + round_to(handler_table->size_in_bytes(), oopSize) 569 + round_to(nul_chk_table->size_in_bytes(), oopSize) 570 + round_to(debug_info->data_size() , oopSize); 571 572 nm = new (nmethod_size) 573 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, 574 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, 575 oop_maps, 576 handler_table, 577 nul_chk_table, 578 compiler, 579 comp_level); 580 581 if (nm != NULL) { 582 // To make dependency checking during class loading fast, record 583 // the nmethod dependencies in the classes it is dependent on. 584 // This allows the dependency checking code to simply walk the 585 // class hierarchy above the loaded class, checking only nmethods 586 // which are dependent on those classes. The slow way is to 587 // check every nmethod for dependencies which makes it linear in 588 // the number of methods compiled. For applications with a lot 589 // classes the slow way is too slow. 590 for (Dependencies::DepStream deps(nm); deps.next(); ) { 591 Klass* klass = deps.context_type(); 592 if (klass == NULL) { 593 continue; // ignore things like evol_method 594 } 595 596 // record this nmethod as dependent on this klass 597 InstanceKlass::cast(klass)->add_dependent_nmethod(nm); 598 } 599 NOT_PRODUCT(nmethod_stats.note_nmethod(nm)); 600 if (PrintAssembly) { 601 Disassembler::decode(nm); 602 } 603 } 604 } 605 // Do verification and logging outside CodeCache_lock. 606 if (nm != NULL) { 607 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet. 608 DEBUG_ONLY(nm->verify();) 609 nm->log_new_nmethod(); 610 } 611 return nm; 612 } 613 614 615 // For native wrappers 616 nmethod::nmethod( 617 Method* method, 618 int nmethod_size, 619 int compile_id, 620 CodeOffsets* offsets, 621 CodeBuffer* code_buffer, 622 int frame_size, 623 ByteSize basic_lock_owner_sp_offset, 624 ByteSize basic_lock_sp_offset, 625 OopMapSet* oop_maps ) 626 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod), 627 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 628 _native_receiver_sp_offset(basic_lock_owner_sp_offset), 629 _native_basic_lock_sp_offset(basic_lock_sp_offset) 630 { 631 { 632 debug_only(No_Safepoint_Verifier nsv;) 633 assert_locked_or_safepoint(CodeCache_lock); 634 635 init_defaults(); 636 _method = method; 637 _entry_bci = InvocationEntryBci; 638 // We have no exception handler or deopt handler make the 639 // values something that will never match a pc like the nmethod vtable entry 640 _exception_offset = 0; 641 _deoptimize_offset = 0; 642 _deoptimize_mh_offset = 0; 643 _orig_pc_offset = 0; 644 645 _consts_offset = data_offset(); 646 _stub_offset = data_offset(); 647 _oops_offset = data_offset(); 648 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 649 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 650 _scopes_pcs_offset = _scopes_data_offset; 651 _dependencies_offset = _scopes_pcs_offset; 652 _handler_table_offset = _dependencies_offset; 653 _nul_chk_table_offset = _handler_table_offset; 654 _nmethod_end_offset = _nul_chk_table_offset; 655 _compile_id = compile_id; 656 _comp_level = CompLevel_none; 657 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 658 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 659 _osr_entry_point = NULL; 660 _exception_cache = NULL; 661 _pc_desc_cache.reset_to(NULL); 662 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 663 664 code_buffer->copy_values_to(this); 665 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 666 CodeCache::add_scavenge_root_nmethod(this); 667 Universe::heap()->register_nmethod(this); 668 } 669 debug_only(verify_scavenge_root_oops()); 670 CodeCache::commit(this); 671 } 672 673 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 674 ttyLocker ttyl; // keep the following output all in one block 675 // This output goes directly to the tty, not the compiler log. 676 // To enable tools to match it up with the compilation activity, 677 // be sure to tag this tty output with the compile ID. 678 if (xtty != NULL) { 679 xtty->begin_head("print_native_nmethod"); 680 xtty->method(_method); 681 xtty->stamp(); 682 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 683 } 684 // print the header part first 685 print(); 686 // then print the requested information 687 if (PrintNativeNMethods) { 688 print_code(); 689 if (oop_maps != NULL) { 690 oop_maps->print(); 691 } 692 } 693 if (PrintRelocations) { 694 print_relocations(); 695 } 696 if (xtty != NULL) { 697 xtty->tail("print_native_nmethod"); 698 } 699 } 700 } 701 702 // For dtrace wrappers 703 #ifdef HAVE_DTRACE_H 704 nmethod::nmethod( 705 Method* method, 706 int nmethod_size, 707 CodeOffsets* offsets, 708 CodeBuffer* code_buffer, 709 int frame_size) 710 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod), 711 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL), 712 _native_receiver_sp_offset(in_ByteSize(-1)), 713 _native_basic_lock_sp_offset(in_ByteSize(-1)) 714 { 715 { 716 debug_only(No_Safepoint_Verifier nsv;) 717 assert_locked_or_safepoint(CodeCache_lock); 718 719 init_defaults(); 720 _method = method; 721 _entry_bci = InvocationEntryBci; 722 // We have no exception handler or deopt handler make the 723 // values something that will never match a pc like the nmethod vtable entry 724 _exception_offset = 0; 725 _deoptimize_offset = 0; 726 _deoptimize_mh_offset = 0; 727 _unwind_handler_offset = -1; 728 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap); 729 _orig_pc_offset = 0; 730 _consts_offset = data_offset(); 731 _stub_offset = data_offset(); 732 _oops_offset = data_offset(); 733 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 734 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 735 _scopes_pcs_offset = _scopes_data_offset; 736 _dependencies_offset = _scopes_pcs_offset; 737 _handler_table_offset = _dependencies_offset; 738 _nul_chk_table_offset = _handler_table_offset; 739 _nmethod_end_offset = _nul_chk_table_offset; 740 _compile_id = 0; // default 741 _comp_level = CompLevel_none; 742 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 743 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 744 _osr_entry_point = NULL; 745 _exception_cache = NULL; 746 _pc_desc_cache.reset_to(NULL); 747 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 748 749 code_buffer->copy_values_to(this); 750 debug_only(verify_scavenge_root_oops()); 751 CodeCache::commit(this); 752 } 753 754 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 755 ttyLocker ttyl; // keep the following output all in one block 756 // This output goes directly to the tty, not the compiler log. 757 // To enable tools to match it up with the compilation activity, 758 // be sure to tag this tty output with the compile ID. 759 if (xtty != NULL) { 760 xtty->begin_head("print_dtrace_nmethod"); 761 xtty->method(_method); 762 xtty->stamp(); 763 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 764 } 765 // print the header part first 766 print(); 767 // then print the requested information 768 if (PrintNMethods) { 769 print_code(); 770 } 771 if (PrintRelocations) { 772 print_relocations(); 773 } 774 if (xtty != NULL) { 775 xtty->tail("print_dtrace_nmethod"); 776 } 777 } 778 } 779 #endif // def HAVE_DTRACE_H 780 781 void* nmethod::operator new(size_t size, int nmethod_size) throw() { 782 // Not critical, may return null if there is too little continuous memory 783 return CodeCache::allocate(nmethod_size); 784 } 785 786 nmethod::nmethod( 787 Method* method, 788 int nmethod_size, 789 int compile_id, 790 int entry_bci, 791 CodeOffsets* offsets, 792 int orig_pc_offset, 793 DebugInformationRecorder* debug_info, 794 Dependencies* dependencies, 795 CodeBuffer *code_buffer, 796 int frame_size, 797 OopMapSet* oop_maps, 798 ExceptionHandlerTable* handler_table, 799 ImplicitExceptionTable* nul_chk_table, 800 AbstractCompiler* compiler, 801 int comp_level 802 ) 803 : CodeBlob("nmethod", code_buffer, sizeof(nmethod), 804 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 805 _native_receiver_sp_offset(in_ByteSize(-1)), 806 _native_basic_lock_sp_offset(in_ByteSize(-1)) 807 { 808 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 809 { 810 debug_only(No_Safepoint_Verifier nsv;) 811 assert_locked_or_safepoint(CodeCache_lock); 812 813 init_defaults(); 814 _method = method; 815 _entry_bci = entry_bci; 816 _compile_id = compile_id; 817 _comp_level = comp_level; 818 _compiler = compiler; 819 _orig_pc_offset = orig_pc_offset; 820 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 821 822 // Section offsets 823 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts()); 824 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs()); 825 826 // Exception handler and deopt handler are in the stub section 827 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set"); 828 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set"); 829 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions); 830 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt); 831 if (offsets->value(CodeOffsets::DeoptMH) != -1) { 832 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH); 833 } else { 834 _deoptimize_mh_offset = -1; 835 } 836 if (offsets->value(CodeOffsets::UnwindHandler) != -1) { 837 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler); 838 } else { 839 _unwind_handler_offset = -1; 840 } 841 842 _oops_offset = data_offset(); 843 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 844 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 845 846 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize); 847 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size()); 848 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize); 849 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize); 850 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize); 851 852 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 853 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 854 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry); 855 _exception_cache = NULL; 856 _pc_desc_cache.reset_to(scopes_pcs_begin()); 857 858 // Copy contents of ScopeDescRecorder to nmethod 859 code_buffer->copy_values_to(this); 860 debug_info->copy_to(this); 861 dependencies->copy_to(this); 862 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 863 CodeCache::add_scavenge_root_nmethod(this); 864 Universe::heap()->register_nmethod(this); 865 } 866 debug_only(verify_scavenge_root_oops()); 867 868 CodeCache::commit(this); 869 870 // Copy contents of ExceptionHandlerTable to nmethod 871 handler_table->copy_to(this); 872 nul_chk_table->copy_to(this); 873 874 // we use the information of entry points to find out if a method is 875 // static or non static 876 assert(compiler->is_c2() || 877 _method->is_static() == (entry_point() == _verified_entry_point), 878 " entry points must be same for static methods and vice versa"); 879 } 880 881 bool printnmethods = PrintNMethods 882 || CompilerOracle::should_print(_method) 883 || CompilerOracle::has_option_string(_method, "PrintNMethods"); 884 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) { 885 print_nmethod(printnmethods); 886 } 887 } 888 889 890 // Print a short set of xml attributes to identify this nmethod. The 891 // output should be embedded in some other element. 892 void nmethod::log_identity(xmlStream* log) const { 893 log->print(" compile_id='%d'", compile_id()); 894 const char* nm_kind = compile_kind(); 895 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind); 896 if (compiler() != NULL) { 897 log->print(" compiler='%s'", compiler()->name()); 898 } 899 if (TieredCompilation) { 900 log->print(" level='%d'", comp_level()); 901 } 902 } 903 904 905 #define LOG_OFFSET(log, name) \ 906 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \ 907 log->print(" " XSTR(name) "_offset='%d'" , \ 908 (intptr_t)name##_begin() - (intptr_t)this) 909 910 911 void nmethod::log_new_nmethod() const { 912 if (LogCompilation && xtty != NULL) { 913 ttyLocker ttyl; 914 HandleMark hm; 915 xtty->begin_elem("nmethod"); 916 log_identity(xtty); 917 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size()); 918 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this); 919 920 LOG_OFFSET(xtty, relocation); 921 LOG_OFFSET(xtty, consts); 922 LOG_OFFSET(xtty, insts); 923 LOG_OFFSET(xtty, stub); 924 LOG_OFFSET(xtty, scopes_data); 925 LOG_OFFSET(xtty, scopes_pcs); 926 LOG_OFFSET(xtty, dependencies); 927 LOG_OFFSET(xtty, handler_table); 928 LOG_OFFSET(xtty, nul_chk_table); 929 LOG_OFFSET(xtty, oops); 930 931 xtty->method(method()); 932 xtty->stamp(); 933 xtty->end_elem(); 934 } 935 } 936 937 #undef LOG_OFFSET 938 939 940 // Print out more verbose output usually for a newly created nmethod. 941 void nmethod::print_on(outputStream* st, const char* msg) const { 942 if (st != NULL) { 943 ttyLocker ttyl; 944 if (WizardMode) { 945 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true); 946 st->print_cr(" (" INTPTR_FORMAT ")", this); 947 } else { 948 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false); 949 } 950 } 951 } 952 953 954 void nmethod::print_nmethod(bool printmethod) { 955 ttyLocker ttyl; // keep the following output all in one block 956 if (xtty != NULL) { 957 xtty->begin_head("print_nmethod"); 958 xtty->stamp(); 959 xtty->end_head(); 960 } 961 // print the header part first 962 print(); 963 // then print the requested information 964 if (printmethod) { 965 print_code(); 966 print_pcs(); 967 if (oop_maps()) { 968 oop_maps()->print(); 969 } 970 } 971 if (PrintDebugInfo) { 972 print_scopes(); 973 } 974 if (PrintRelocations) { 975 print_relocations(); 976 } 977 if (PrintDependencies) { 978 print_dependencies(); 979 } 980 if (PrintExceptionHandlers) { 981 print_handler_table(); 982 print_nul_chk_table(); 983 } 984 if (xtty != NULL) { 985 xtty->tail("print_nmethod"); 986 } 987 } 988 989 990 // Promote one word from an assembly-time handle to a live embedded oop. 991 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) { 992 if (handle == NULL || 993 // As a special case, IC oops are initialized to 1 or -1. 994 handle == (jobject) Universe::non_oop_word()) { 995 (*dest) = (oop) handle; 996 } else { 997 (*dest) = JNIHandles::resolve_non_null(handle); 998 } 999 } 1000 1001 1002 // Have to have the same name because it's called by a template 1003 void nmethod::copy_values(GrowableArray<jobject>* array) { 1004 int length = array->length(); 1005 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough"); 1006 oop* dest = oops_begin(); 1007 for (int index = 0 ; index < length; index++) { 1008 initialize_immediate_oop(&dest[index], array->at(index)); 1009 } 1010 1011 // Now we can fix up all the oops in the code. We need to do this 1012 // in the code because the assembler uses jobjects as placeholders. 1013 // The code and relocations have already been initialized by the 1014 // CodeBlob constructor, so it is valid even at this early point to 1015 // iterate over relocations and patch the code. 1016 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true); 1017 } 1018 1019 void nmethod::copy_values(GrowableArray<Metadata*>* array) { 1020 int length = array->length(); 1021 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough"); 1022 Metadata** dest = metadata_begin(); 1023 for (int index = 0 ; index < length; index++) { 1024 dest[index] = array->at(index); 1025 } 1026 } 1027 1028 bool nmethod::is_at_poll_return(address pc) { 1029 RelocIterator iter(this, pc, pc+1); 1030 while (iter.next()) { 1031 if (iter.type() == relocInfo::poll_return_type) 1032 return true; 1033 } 1034 return false; 1035 } 1036 1037 1038 bool nmethod::is_at_poll_or_poll_return(address pc) { 1039 RelocIterator iter(this, pc, pc+1); 1040 while (iter.next()) { 1041 relocInfo::relocType t = iter.type(); 1042 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type) 1043 return true; 1044 } 1045 return false; 1046 } 1047 1048 1049 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) { 1050 // re-patch all oop-bearing instructions, just in case some oops moved 1051 RelocIterator iter(this, begin, end); 1052 while (iter.next()) { 1053 if (iter.type() == relocInfo::oop_type) { 1054 oop_Relocation* reloc = iter.oop_reloc(); 1055 if (initialize_immediates && reloc->oop_is_immediate()) { 1056 oop* dest = reloc->oop_addr(); 1057 initialize_immediate_oop(dest, (jobject) *dest); 1058 } 1059 // Refresh the oop-related bits of this instruction. 1060 reloc->fix_oop_relocation(); 1061 } else if (iter.type() == relocInfo::metadata_type) { 1062 metadata_Relocation* reloc = iter.metadata_reloc(); 1063 reloc->fix_metadata_relocation(); 1064 } 1065 } 1066 } 1067 1068 1069 void nmethod::verify_oop_relocations() { 1070 // Ensure sure that the code matches the current oop values 1071 RelocIterator iter(this, NULL, NULL); 1072 while (iter.next()) { 1073 if (iter.type() == relocInfo::oop_type) { 1074 oop_Relocation* reloc = iter.oop_reloc(); 1075 if (!reloc->oop_is_immediate()) { 1076 reloc->verify_oop_relocation(); 1077 } 1078 } 1079 } 1080 } 1081 1082 1083 ScopeDesc* nmethod::scope_desc_at(address pc) { 1084 PcDesc* pd = pc_desc_at(pc); 1085 guarantee(pd != NULL, "scope must be present"); 1086 return new ScopeDesc(this, pd->scope_decode_offset(), 1087 pd->obj_decode_offset(), pd->should_reexecute(), 1088 pd->return_oop()); 1089 } 1090 1091 1092 void nmethod::clear_inline_caches() { 1093 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint"); 1094 if (is_zombie()) { 1095 return; 1096 } 1097 1098 RelocIterator iter(this); 1099 while (iter.next()) { 1100 iter.reloc()->clear_inline_cache(); 1101 } 1102 } 1103 1104 1105 void nmethod::cleanup_inline_caches() { 1106 1107 assert_locked_or_safepoint(CompiledIC_lock); 1108 1109 // If the method is not entrant or zombie then a JMP is plastered over the 1110 // first few bytes. If an oop in the old code was there, that oop 1111 // should not get GC'd. Skip the first few bytes of oops on 1112 // not-entrant methods. 1113 address low_boundary = verified_entry_point(); 1114 if (!is_in_use()) { 1115 low_boundary += NativeJump::instruction_size; 1116 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1117 // This means that the low_boundary is going to be a little too high. 1118 // This shouldn't matter, since oops of non-entrant methods are never used. 1119 // In fact, why are we bothering to look at oops in a non-entrant method?? 1120 } 1121 1122 // Find all calls in an nmethod, and clear the ones that points to zombie methods 1123 ResourceMark rm; 1124 RelocIterator iter(this, low_boundary); 1125 while(iter.next()) { 1126 switch(iter.type()) { 1127 case relocInfo::virtual_call_type: 1128 case relocInfo::opt_virtual_call_type: { 1129 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1130 // Ok, to lookup references to zombies here 1131 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1132 if( cb != NULL && cb->is_nmethod() ) { 1133 nmethod* nm = (nmethod*)cb; 1134 // Clean inline caches pointing to both zombie and not_entrant methods 1135 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(); 1136 } 1137 break; 1138 } 1139 case relocInfo::static_call_type: { 1140 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1141 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1142 if( cb != NULL && cb->is_nmethod() ) { 1143 nmethod* nm = (nmethod*)cb; 1144 // Clean inline caches pointing to both zombie and not_entrant methods 1145 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean(); 1146 } 1147 break; 1148 } 1149 } 1150 } 1151 } 1152 1153 // This is a private interface with the sweeper. 1154 void nmethod::mark_as_seen_on_stack() { 1155 assert(is_alive(), "Must be an alive method"); 1156 // Set the traversal mark to ensure that the sweeper does 2 1157 // cleaning passes before moving to zombie. 1158 set_stack_traversal_mark(NMethodSweeper::traversal_count()); 1159 } 1160 1161 // Tell if a non-entrant method can be converted to a zombie (i.e., 1162 // there are no activations on the stack, not in use by the VM, 1163 // and not in use by the ServiceThread) 1164 bool nmethod::can_not_entrant_be_converted() { 1165 assert(is_not_entrant(), "must be a non-entrant method"); 1166 1167 // Since the nmethod sweeper only does partial sweep the sweeper's traversal 1168 // count can be greater than the stack traversal count before it hits the 1169 // nmethod for the second time. 1170 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() && 1171 !is_locked_by_vm(); 1172 } 1173 1174 void nmethod::inc_decompile_count() { 1175 if (!is_compiled_by_c2()) return; 1176 // Could be gated by ProfileTraps, but do not bother... 1177 Method* m = method(); 1178 if (m == NULL) return; 1179 MethodData* mdo = m->method_data(); 1180 if (mdo == NULL) return; 1181 // There is a benign race here. See comments in methodData.hpp. 1182 mdo->inc_decompile_count(); 1183 } 1184 1185 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) { 1186 1187 post_compiled_method_unload(); 1188 1189 // Since this nmethod is being unloaded, make sure that dependencies 1190 // recorded in instanceKlasses get flushed and pass non-NULL closure to 1191 // indicate that this work is being done during a GC. 1192 assert(Universe::heap()->is_gc_active(), "should only be called during gc"); 1193 assert(is_alive != NULL, "Should be non-NULL"); 1194 // A non-NULL is_alive closure indicates that this is being called during GC. 1195 flush_dependencies(is_alive); 1196 1197 // Break cycle between nmethod & method 1198 if (TraceClassUnloading && WizardMode) { 1199 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT 1200 " unloadable], Method*(" INTPTR_FORMAT 1201 "), cause(" INTPTR_FORMAT ")", 1202 this, (address)_method, (address)cause); 1203 if (!Universe::heap()->is_gc_active()) 1204 cause->klass()->print(); 1205 } 1206 // Unlink the osr method, so we do not look this up again 1207 if (is_osr_method()) { 1208 invalidate_osr_method(); 1209 } 1210 // If _method is already NULL the Method* is about to be unloaded, 1211 // so we don't have to break the cycle. Note that it is possible to 1212 // have the Method* live here, in case we unload the nmethod because 1213 // it is pointing to some oop (other than the Method*) being unloaded. 1214 if (_method != NULL) { 1215 // OSR methods point to the Method*, but the Method* does not 1216 // point back! 1217 if (_method->code() == this) { 1218 _method->clear_code(); // Break a cycle 1219 } 1220 _method = NULL; // Clear the method of this dead nmethod 1221 } 1222 // Make the class unloaded - i.e., change state and notify sweeper 1223 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1224 if (is_in_use()) { 1225 // Transitioning directly from live to unloaded -- so 1226 // we need to force a cache clean-up; remember this 1227 // for later on. 1228 CodeCache::set_needs_cache_clean(true); 1229 } 1230 _state = unloaded; 1231 1232 // Log the unloading. 1233 log_state_change(); 1234 1235 // The Method* is gone at this point 1236 assert(_method == NULL, "Tautology"); 1237 1238 set_osr_link(NULL); 1239 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods 1240 NMethodSweeper::report_state_change(this); 1241 } 1242 1243 void nmethod::invalidate_osr_method() { 1244 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); 1245 // Remove from list of active nmethods 1246 if (method() != NULL) 1247 method()->method_holder()->remove_osr_nmethod(this); 1248 // Set entry as invalid 1249 _entry_bci = InvalidOSREntryBci; 1250 } 1251 1252 void nmethod::log_state_change() const { 1253 if (LogCompilation) { 1254 if (xtty != NULL) { 1255 ttyLocker ttyl; // keep the following output all in one block 1256 if (_state == unloaded) { 1257 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'", 1258 os::current_thread_id()); 1259 } else { 1260 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s", 1261 os::current_thread_id(), 1262 (_state == zombie ? " zombie='1'" : "")); 1263 } 1264 log_identity(xtty); 1265 xtty->stamp(); 1266 xtty->end_elem(); 1267 } 1268 } 1269 if (PrintCompilation && _state != unloaded) { 1270 print_on(tty, _state == zombie ? "made zombie" : "made not entrant"); 1271 } 1272 } 1273 1274 /** 1275 * Common functionality for both make_not_entrant and make_zombie 1276 */ 1277 bool nmethod::make_not_entrant_or_zombie(unsigned int state) { 1278 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant"); 1279 assert(!is_zombie(), "should not already be a zombie"); 1280 1281 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below. 1282 nmethodLocker nml(this); 1283 methodHandle the_method(method()); 1284 No_Safepoint_Verifier nsv; 1285 1286 // during patching, depending on the nmethod state we must notify the GC that 1287 // code has been unloaded, unregistering it. We cannot do this right while 1288 // holding the Patching_lock because we need to use the CodeCache_lock. This 1289 // would be prone to deadlocks. 1290 // This flag is used to remember whether we need to later lock and unregister. 1291 bool nmethod_needs_unregister = false; 1292 1293 { 1294 // invalidate osr nmethod before acquiring the patching lock since 1295 // they both acquire leaf locks and we don't want a deadlock. 1296 // This logic is equivalent to the logic below for patching the 1297 // verified entry point of regular methods. 1298 if (is_osr_method()) { 1299 // this effectively makes the osr nmethod not entrant 1300 invalidate_osr_method(); 1301 } 1302 1303 // Enter critical section. Does not block for safepoint. 1304 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1305 1306 if (_state == state) { 1307 // another thread already performed this transition so nothing 1308 // to do, but return false to indicate this. 1309 return false; 1310 } 1311 1312 // The caller can be calling the method statically or through an inline 1313 // cache call. 1314 if (!is_osr_method() && !is_not_entrant()) { 1315 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(), 1316 SharedRuntime::get_handle_wrong_method_stub()); 1317 } 1318 1319 if (is_in_use()) { 1320 // It's a true state change, so mark the method as decompiled. 1321 // Do it only for transition from alive. 1322 inc_decompile_count(); 1323 } 1324 1325 // If the state is becoming a zombie, signal to unregister the nmethod with 1326 // the heap. 1327 // This nmethod may have already been unloaded during a full GC. 1328 if ((state == zombie) && !is_unloaded()) { 1329 nmethod_needs_unregister = true; 1330 } 1331 1332 // Must happen before state change. Otherwise we have a race condition in 1333 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately 1334 // transition its state from 'not_entrant' to 'zombie' without having to wait 1335 // for stack scanning. 1336 if (state == not_entrant) { 1337 mark_as_seen_on_stack(); 1338 OrderAccess::storestore(); 1339 } 1340 1341 // Change state 1342 _state = state; 1343 1344 // Log the transition once 1345 log_state_change(); 1346 1347 // Remove nmethod from method. 1348 // We need to check if both the _code and _from_compiled_code_entry_point 1349 // refer to this nmethod because there is a race in setting these two fields 1350 // in Method* as seen in bugid 4947125. 1351 // If the vep() points to the zombie nmethod, the memory for the nmethod 1352 // could be flushed and the compiler and vtable stubs could still call 1353 // through it. 1354 if (method() != NULL && (method()->code() == this || 1355 method()->from_compiled_entry() == verified_entry_point())) { 1356 HandleMark hm; 1357 method()->clear_code(); 1358 } 1359 } // leave critical region under Patching_lock 1360 1361 // When the nmethod becomes zombie it is no longer alive so the 1362 // dependencies must be flushed. nmethods in the not_entrant 1363 // state will be flushed later when the transition to zombie 1364 // happens or they get unloaded. 1365 if (state == zombie) { 1366 { 1367 // Flushing dependecies must be done before any possible 1368 // safepoint can sneak in, otherwise the oops used by the 1369 // dependency logic could have become stale. 1370 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1371 if (nmethod_needs_unregister) { 1372 Universe::heap()->unregister_nmethod(this); 1373 } 1374 flush_dependencies(NULL); 1375 } 1376 1377 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload 1378 // event and it hasn't already been reported for this nmethod then 1379 // report it now. The event may have been reported earilier if the GC 1380 // marked it for unloading). JvmtiDeferredEventQueue support means 1381 // we no longer go to a safepoint here. 1382 post_compiled_method_unload(); 1383 1384 #ifdef ASSERT 1385 // It's no longer safe to access the oops section since zombie 1386 // nmethods aren't scanned for GC. 1387 _oops_are_stale = true; 1388 #endif 1389 // the Method may be reclaimed by class unloading now that the 1390 // nmethod is in zombie state 1391 set_method(NULL); 1392 } else { 1393 assert(state == not_entrant, "other cases may need to be handled differently"); 1394 } 1395 1396 if (TraceCreateZombies) { 1397 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie"); 1398 } 1399 1400 NMethodSweeper::report_state_change(this); 1401 return true; 1402 } 1403 1404 void nmethod::flush() { 1405 // Note that there are no valid oops in the nmethod anymore. 1406 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method"); 1407 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation"); 1408 1409 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed"); 1410 assert_locked_or_safepoint(CodeCache_lock); 1411 1412 // completely deallocate this method 1413 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this); 1414 if (PrintMethodFlushing) { 1415 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb", 1416 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024); 1417 } 1418 1419 // We need to deallocate any ExceptionCache data. 1420 // Note that we do not need to grab the nmethod lock for this, it 1421 // better be thread safe if we're disposing of it! 1422 ExceptionCache* ec = exception_cache(); 1423 set_exception_cache(NULL); 1424 while(ec != NULL) { 1425 ExceptionCache* next = ec->next(); 1426 delete ec; 1427 ec = next; 1428 } 1429 1430 if (on_scavenge_root_list()) { 1431 CodeCache::drop_scavenge_root_nmethod(this); 1432 } 1433 1434 #ifdef SHARK 1435 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin()); 1436 #endif // SHARK 1437 1438 ((CodeBlob*)(this))->flush(); 1439 1440 CodeCache::free(this); 1441 } 1442 1443 1444 // 1445 // Notify all classes this nmethod is dependent on that it is no 1446 // longer dependent. This should only be called in two situations. 1447 // First, when a nmethod transitions to a zombie all dependents need 1448 // to be clear. Since zombification happens at a safepoint there's no 1449 // synchronization issues. The second place is a little more tricky. 1450 // During phase 1 of mark sweep class unloading may happen and as a 1451 // result some nmethods may get unloaded. In this case the flushing 1452 // of dependencies must happen during phase 1 since after GC any 1453 // dependencies in the unloaded nmethod won't be updated, so 1454 // traversing the dependency information in unsafe. In that case this 1455 // function is called with a non-NULL argument and this function only 1456 // notifies instanceKlasses that are reachable 1457 1458 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) { 1459 assert_locked_or_safepoint(CodeCache_lock); 1460 assert(Universe::heap()->is_gc_active() == (is_alive != NULL), 1461 "is_alive is non-NULL if and only if we are called during GC"); 1462 if (!has_flushed_dependencies()) { 1463 set_has_flushed_dependencies(); 1464 for (Dependencies::DepStream deps(this); deps.next(); ) { 1465 Klass* klass = deps.context_type(); 1466 if (klass == NULL) continue; // ignore things like evol_method 1467 1468 // During GC the is_alive closure is non-NULL, and is used to 1469 // determine liveness of dependees that need to be updated. 1470 if (is_alive == NULL || klass->is_loader_alive(is_alive)) { 1471 InstanceKlass::cast(klass)->remove_dependent_nmethod(this); 1472 } 1473 } 1474 } 1475 } 1476 1477 1478 // If this oop is not live, the nmethod can be unloaded. 1479 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) { 1480 assert(root != NULL, "just checking"); 1481 oop obj = *root; 1482 if (obj == NULL || is_alive->do_object_b(obj)) { 1483 return false; 1484 } 1485 1486 // If ScavengeRootsInCode is true, an nmethod might be unloaded 1487 // simply because one of its constant oops has gone dead. 1488 // No actual classes need to be unloaded in order for this to occur. 1489 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading"); 1490 make_unloaded(is_alive, obj); 1491 return true; 1492 } 1493 1494 // ------------------------------------------------------------------ 1495 // post_compiled_method_load_event 1496 // new method for install_code() path 1497 // Transfer information from compilation to jvmti 1498 void nmethod::post_compiled_method_load_event() { 1499 1500 Method* moop = method(); 1501 HOTSPOT_COMPILED_METHOD_LOAD( 1502 (char *) moop->klass_name()->bytes(), 1503 moop->klass_name()->utf8_length(), 1504 (char *) moop->name()->bytes(), 1505 moop->name()->utf8_length(), 1506 (char *) moop->signature()->bytes(), 1507 moop->signature()->utf8_length(), 1508 insts_begin(), insts_size()); 1509 1510 if (JvmtiExport::should_post_compiled_method_load() || 1511 JvmtiExport::should_post_compiled_method_unload()) { 1512 get_and_cache_jmethod_id(); 1513 } 1514 1515 if (JvmtiExport::should_post_compiled_method_load()) { 1516 // Let the Service thread (which is a real Java thread) post the event 1517 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1518 JvmtiDeferredEventQueue::enqueue( 1519 JvmtiDeferredEvent::compiled_method_load_event(this)); 1520 } 1521 } 1522 1523 jmethodID nmethod::get_and_cache_jmethod_id() { 1524 if (_jmethod_id == NULL) { 1525 // Cache the jmethod_id since it can no longer be looked up once the 1526 // method itself has been marked for unloading. 1527 _jmethod_id = method()->jmethod_id(); 1528 } 1529 return _jmethod_id; 1530 } 1531 1532 void nmethod::post_compiled_method_unload() { 1533 if (unload_reported()) { 1534 // During unloading we transition to unloaded and then to zombie 1535 // and the unloading is reported during the first transition. 1536 return; 1537 } 1538 1539 assert(_method != NULL && !is_unloaded(), "just checking"); 1540 DTRACE_METHOD_UNLOAD_PROBE(method()); 1541 1542 // If a JVMTI agent has enabled the CompiledMethodUnload event then 1543 // post the event. Sometime later this nmethod will be made a zombie 1544 // by the sweeper but the Method* will not be valid at that point. 1545 // If the _jmethod_id is null then no load event was ever requested 1546 // so don't bother posting the unload. The main reason for this is 1547 // that the jmethodID is a weak reference to the Method* so if 1548 // it's being unloaded there's no way to look it up since the weak 1549 // ref will have been cleared. 1550 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) { 1551 assert(!unload_reported(), "already unloaded"); 1552 JvmtiDeferredEvent event = 1553 JvmtiDeferredEvent::compiled_method_unload_event(this, 1554 _jmethod_id, insts_begin()); 1555 if (SafepointSynchronize::is_at_safepoint()) { 1556 // Don't want to take the queueing lock. Add it as pending and 1557 // it will get enqueued later. 1558 JvmtiDeferredEventQueue::add_pending_event(event); 1559 } else { 1560 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1561 JvmtiDeferredEventQueue::enqueue(event); 1562 } 1563 } 1564 1565 // The JVMTI CompiledMethodUnload event can be enabled or disabled at 1566 // any time. As the nmethod is being unloaded now we mark it has 1567 // having the unload event reported - this will ensure that we don't 1568 // attempt to report the event in the unlikely scenario where the 1569 // event is enabled at the time the nmethod is made a zombie. 1570 set_unload_reported(); 1571 } 1572 1573 // This is called at the end of the strong tracing/marking phase of a 1574 // GC to unload an nmethod if it contains otherwise unreachable 1575 // oops. 1576 1577 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) { 1578 // Make sure the oop's ready to receive visitors 1579 assert(!is_zombie() && !is_unloaded(), 1580 "should not call follow on zombie or unloaded nmethod"); 1581 1582 // If the method is not entrant then a JMP is plastered over the 1583 // first few bytes. If an oop in the old code was there, that oop 1584 // should not get GC'd. Skip the first few bytes of oops on 1585 // not-entrant methods. 1586 address low_boundary = verified_entry_point(); 1587 if (is_not_entrant()) { 1588 low_boundary += NativeJump::instruction_size; 1589 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1590 // (See comment above.) 1591 } 1592 1593 // The RedefineClasses() API can cause the class unloading invariant 1594 // to no longer be true. See jvmtiExport.hpp for details. 1595 // Also, leave a debugging breadcrumb in local flag. 1596 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class(); 1597 if (a_class_was_redefined) { 1598 // This set of the unloading_occurred flag is done before the 1599 // call to post_compiled_method_unload() so that the unloading 1600 // of this nmethod is reported. 1601 unloading_occurred = true; 1602 } 1603 1604 // Exception cache 1605 ExceptionCache* ec = exception_cache(); 1606 while (ec != NULL) { 1607 Klass* ex_klass = ec->exception_type(); 1608 ExceptionCache* next_ec = ec->next(); 1609 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) { 1610 remove_from_exception_cache(ec); 1611 } 1612 ec = next_ec; 1613 } 1614 1615 // If class unloading occurred we first iterate over all inline caches and 1616 // clear ICs where the cached oop is referring to an unloaded klass or method. 1617 // The remaining live cached oops will be traversed in the relocInfo::oop_type 1618 // iteration below. 1619 if (unloading_occurred) { 1620 RelocIterator iter(this, low_boundary); 1621 while(iter.next()) { 1622 if (iter.type() == relocInfo::virtual_call_type) { 1623 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1624 if (ic->is_icholder_call()) { 1625 // The only exception is compiledICHolder oops which may 1626 // yet be marked below. (We check this further below). 1627 CompiledICHolder* cichk_oop = ic->cached_icholder(); 1628 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) && 1629 cichk_oop->holder_klass()->is_loader_alive(is_alive)) { 1630 continue; 1631 } 1632 } else { 1633 Metadata* ic_oop = ic->cached_metadata(); 1634 if (ic_oop != NULL) { 1635 if (ic_oop->is_klass()) { 1636 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) { 1637 continue; 1638 } 1639 } else if (ic_oop->is_method()) { 1640 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) { 1641 continue; 1642 } 1643 } else { 1644 ShouldNotReachHere(); 1645 } 1646 } 1647 } 1648 ic->set_to_clean(); 1649 } 1650 } 1651 } 1652 1653 // Compiled code 1654 { 1655 RelocIterator iter(this, low_boundary); 1656 while (iter.next()) { 1657 if (iter.type() == relocInfo::oop_type) { 1658 oop_Relocation* r = iter.oop_reloc(); 1659 // In this loop, we must only traverse those oops directly embedded in 1660 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1661 assert(1 == (r->oop_is_immediate()) + 1662 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1663 "oop must be found in exactly one place"); 1664 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1665 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) { 1666 return; 1667 } 1668 } 1669 } 1670 } 1671 } 1672 1673 1674 // Scopes 1675 for (oop* p = oops_begin(); p < oops_end(); p++) { 1676 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1677 if (can_unload(is_alive, p, unloading_occurred)) { 1678 return; 1679 } 1680 } 1681 1682 // Ensure that all metadata is still alive 1683 verify_metadata_loaders(low_boundary, is_alive); 1684 } 1685 1686 #ifdef ASSERT 1687 1688 class CheckClass : AllStatic { 1689 static BoolObjectClosure* _is_alive; 1690 1691 // Check class_loader is alive for this bit of metadata. 1692 static void check_class(Metadata* md) { 1693 Klass* klass = NULL; 1694 if (md->is_klass()) { 1695 klass = ((Klass*)md); 1696 } else if (md->is_method()) { 1697 klass = ((Method*)md)->method_holder(); 1698 } else if (md->is_methodData()) { 1699 klass = ((MethodData*)md)->method()->method_holder(); 1700 } else { 1701 md->print(); 1702 ShouldNotReachHere(); 1703 } 1704 assert(klass->is_loader_alive(_is_alive), "must be alive"); 1705 } 1706 public: 1707 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) { 1708 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint"); 1709 _is_alive = is_alive; 1710 nm->metadata_do(check_class); 1711 } 1712 }; 1713 1714 // This is called during a safepoint so can use static data 1715 BoolObjectClosure* CheckClass::_is_alive = NULL; 1716 #endif // ASSERT 1717 1718 1719 // Processing of oop references should have been sufficient to keep 1720 // all strong references alive. Any weak references should have been 1721 // cleared as well. Visit all the metadata and ensure that it's 1722 // really alive. 1723 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) { 1724 #ifdef ASSERT 1725 RelocIterator iter(this, low_boundary); 1726 while (iter.next()) { 1727 // static_stub_Relocations may have dangling references to 1728 // Method*s so trim them out here. Otherwise it looks like 1729 // compiled code is maintaining a link to dead metadata. 1730 address static_call_addr = NULL; 1731 if (iter.type() == relocInfo::opt_virtual_call_type) { 1732 CompiledIC* cic = CompiledIC_at(iter.reloc()); 1733 if (!cic->is_call_to_interpreted()) { 1734 static_call_addr = iter.addr(); 1735 } 1736 } else if (iter.type() == relocInfo::static_call_type) { 1737 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc()); 1738 if (!csc->is_call_to_interpreted()) { 1739 static_call_addr = iter.addr(); 1740 } 1741 } 1742 if (static_call_addr != NULL) { 1743 RelocIterator sciter(this, low_boundary); 1744 while (sciter.next()) { 1745 if (sciter.type() == relocInfo::static_stub_type && 1746 sciter.static_stub_reloc()->static_call() == static_call_addr) { 1747 sciter.static_stub_reloc()->clear_inline_cache(); 1748 } 1749 } 1750 } 1751 } 1752 // Check that the metadata embedded in the nmethod is alive 1753 CheckClass::do_check_class(is_alive, this); 1754 #endif 1755 } 1756 1757 1758 // Iterate over metadata calling this function. Used by RedefineClasses 1759 void nmethod::metadata_do(void f(Metadata*)) { 1760 address low_boundary = verified_entry_point(); 1761 if (is_not_entrant()) { 1762 low_boundary += NativeJump::instruction_size; 1763 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1764 // (See comment above.) 1765 } 1766 { 1767 // Visit all immediate references that are embedded in the instruction stream. 1768 RelocIterator iter(this, low_boundary); 1769 while (iter.next()) { 1770 if (iter.type() == relocInfo::metadata_type ) { 1771 metadata_Relocation* r = iter.metadata_reloc(); 1772 // In this lmetadata, we must only follow those metadatas directly embedded in 1773 // the code. Other metadatas (oop_index>0) are seen as part of 1774 // the metadata section below. 1775 assert(1 == (r->metadata_is_immediate()) + 1776 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), 1777 "metadata must be found in exactly one place"); 1778 if (r->metadata_is_immediate() && r->metadata_value() != NULL) { 1779 Metadata* md = r->metadata_value(); 1780 f(md); 1781 } 1782 } else if (iter.type() == relocInfo::virtual_call_type) { 1783 // Check compiledIC holders associated with this nmethod 1784 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1785 if (ic->is_icholder_call()) { 1786 CompiledICHolder* cichk = ic->cached_icholder(); 1787 f(cichk->holder_method()); 1788 f(cichk->holder_klass()); 1789 } else { 1790 Metadata* ic_oop = ic->cached_metadata(); 1791 if (ic_oop != NULL) { 1792 f(ic_oop); 1793 } 1794 } 1795 } 1796 } 1797 } 1798 1799 // Visit the metadata section 1800 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { 1801 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops 1802 Metadata* md = *p; 1803 f(md); 1804 } 1805 1806 // Call function Method*, not embedded in these other places. 1807 if (_method != NULL) f(_method); 1808 } 1809 1810 void nmethod::oops_do(OopClosure* f, bool allow_zombie) { 1811 // make sure the oops ready to receive visitors 1812 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod"); 1813 assert(!is_unloaded(), "should not call follow on unloaded nmethod"); 1814 1815 // If the method is not entrant or zombie then a JMP is plastered over the 1816 // first few bytes. If an oop in the old code was there, that oop 1817 // should not get GC'd. Skip the first few bytes of oops on 1818 // not-entrant methods. 1819 address low_boundary = verified_entry_point(); 1820 if (is_not_entrant()) { 1821 low_boundary += NativeJump::instruction_size; 1822 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1823 // (See comment above.) 1824 } 1825 1826 RelocIterator iter(this, low_boundary); 1827 1828 while (iter.next()) { 1829 if (iter.type() == relocInfo::oop_type ) { 1830 oop_Relocation* r = iter.oop_reloc(); 1831 // In this loop, we must only follow those oops directly embedded in 1832 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1833 assert(1 == (r->oop_is_immediate()) + 1834 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1835 "oop must be found in exactly one place"); 1836 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1837 f->do_oop(r->oop_addr()); 1838 } 1839 } 1840 } 1841 1842 // Scopes 1843 // This includes oop constants not inlined in the code stream. 1844 for (oop* p = oops_begin(); p < oops_end(); p++) { 1845 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1846 f->do_oop(p); 1847 } 1848 } 1849 1850 #define NMETHOD_SENTINEL ((nmethod*)badAddress) 1851 1852 nmethod* volatile nmethod::_oops_do_mark_nmethods; 1853 1854 // An nmethod is "marked" if its _mark_link is set non-null. 1855 // Even if it is the end of the linked list, it will have a non-null link value, 1856 // as long as it is on the list. 1857 // This code must be MP safe, because it is used from parallel GC passes. 1858 bool nmethod::test_set_oops_do_mark() { 1859 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called"); 1860 nmethod* observed_mark_link = _oops_do_mark_link; 1861 if (observed_mark_link == NULL) { 1862 // Claim this nmethod for this thread to mark. 1863 observed_mark_link = (nmethod*) 1864 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL); 1865 if (observed_mark_link == NULL) { 1866 1867 // Atomically append this nmethod (now claimed) to the head of the list: 1868 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods; 1869 for (;;) { 1870 nmethod* required_mark_nmethods = observed_mark_nmethods; 1871 _oops_do_mark_link = required_mark_nmethods; 1872 observed_mark_nmethods = (nmethod*) 1873 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods); 1874 if (observed_mark_nmethods == required_mark_nmethods) 1875 break; 1876 } 1877 // Mark was clear when we first saw this guy. 1878 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark")); 1879 return false; 1880 } 1881 } 1882 // On fall through, another racing thread marked this nmethod before we did. 1883 return true; 1884 } 1885 1886 void nmethod::oops_do_marking_prologue() { 1887 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue")); 1888 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row"); 1889 // We use cmpxchg_ptr instead of regular assignment here because the user 1890 // may fork a bunch of threads, and we need them all to see the same state. 1891 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL); 1892 guarantee(observed == NULL, "no races in this sequential code"); 1893 } 1894 1895 void nmethod::oops_do_marking_epilogue() { 1896 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row"); 1897 nmethod* cur = _oops_do_mark_nmethods; 1898 while (cur != NMETHOD_SENTINEL) { 1899 assert(cur != NULL, "not NULL-terminated"); 1900 nmethod* next = cur->_oops_do_mark_link; 1901 cur->_oops_do_mark_link = NULL; 1902 cur->fix_oop_relocations(); 1903 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark")); 1904 cur = next; 1905 } 1906 void* required = _oops_do_mark_nmethods; 1907 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required); 1908 guarantee(observed == required, "no races in this sequential code"); 1909 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]")); 1910 } 1911 1912 class DetectScavengeRoot: public OopClosure { 1913 bool _detected_scavenge_root; 1914 public: 1915 DetectScavengeRoot() : _detected_scavenge_root(false) 1916 { NOT_PRODUCT(_print_nm = NULL); } 1917 bool detected_scavenge_root() { return _detected_scavenge_root; } 1918 virtual void do_oop(oop* p) { 1919 if ((*p) != NULL && (*p)->is_scavengable()) { 1920 NOT_PRODUCT(maybe_print(p)); 1921 _detected_scavenge_root = true; 1922 } 1923 } 1924 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 1925 1926 #ifndef PRODUCT 1927 nmethod* _print_nm; 1928 void maybe_print(oop* p) { 1929 if (_print_nm == NULL) return; 1930 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root"); 1931 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")", 1932 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm), 1933 (void *)(*p), (intptr_t)p); 1934 (*p)->print(); 1935 } 1936 #endif //PRODUCT 1937 }; 1938 1939 bool nmethod::detect_scavenge_root_oops() { 1940 DetectScavengeRoot detect_scavenge_root; 1941 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this); 1942 oops_do(&detect_scavenge_root); 1943 return detect_scavenge_root.detected_scavenge_root(); 1944 } 1945 1946 // Method that knows how to preserve outgoing arguments at call. This method must be 1947 // called with a frame corresponding to a Java invoke 1948 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { 1949 #ifndef SHARK 1950 if (!method()->is_native()) { 1951 SimpleScopeDesc ssd(this, fr.pc()); 1952 Bytecode_invoke call(ssd.method(), ssd.bci()); 1953 bool has_receiver = call.has_receiver(); 1954 bool has_appendix = call.has_appendix(); 1955 Symbol* signature = call.signature(); 1956 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f); 1957 } 1958 #endif // !SHARK 1959 } 1960 1961 1962 oop nmethod::embeddedOop_at(u_char* p) { 1963 RelocIterator iter(this, p, p + 1); 1964 while (iter.next()) 1965 if (iter.type() == relocInfo::oop_type) { 1966 return iter.oop_reloc()->oop_value(); 1967 } 1968 return NULL; 1969 } 1970 1971 1972 inline bool includes(void* p, void* from, void* to) { 1973 return from <= p && p < to; 1974 } 1975 1976 1977 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) { 1978 assert(count >= 2, "must be sentinel values, at least"); 1979 1980 #ifdef ASSERT 1981 // must be sorted and unique; we do a binary search in find_pc_desc() 1982 int prev_offset = pcs[0].pc_offset(); 1983 assert(prev_offset == PcDesc::lower_offset_limit, 1984 "must start with a sentinel"); 1985 for (int i = 1; i < count; i++) { 1986 int this_offset = pcs[i].pc_offset(); 1987 assert(this_offset > prev_offset, "offsets must be sorted"); 1988 prev_offset = this_offset; 1989 } 1990 assert(prev_offset == PcDesc::upper_offset_limit, 1991 "must end with a sentinel"); 1992 #endif //ASSERT 1993 1994 // Search for MethodHandle invokes and tag the nmethod. 1995 for (int i = 0; i < count; i++) { 1996 if (pcs[i].is_method_handle_invoke()) { 1997 set_has_method_handle_invokes(true); 1998 break; 1999 } 2000 } 2001 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler"); 2002 2003 int size = count * sizeof(PcDesc); 2004 assert(scopes_pcs_size() >= size, "oob"); 2005 memcpy(scopes_pcs_begin(), pcs, size); 2006 2007 // Adjust the final sentinel downward. 2008 PcDesc* last_pc = &scopes_pcs_begin()[count-1]; 2009 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity"); 2010 last_pc->set_pc_offset(content_size() + 1); 2011 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { 2012 // Fill any rounding gaps with copies of the last record. 2013 last_pc[1] = last_pc[0]; 2014 } 2015 // The following assert could fail if sizeof(PcDesc) is not 2016 // an integral multiple of oopSize (the rounding term). 2017 // If it fails, change the logic to always allocate a multiple 2018 // of sizeof(PcDesc), and fill unused words with copies of *last_pc. 2019 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly"); 2020 } 2021 2022 void nmethod::copy_scopes_data(u_char* buffer, int size) { 2023 assert(scopes_data_size() >= size, "oob"); 2024 memcpy(scopes_data_begin(), buffer, size); 2025 } 2026 2027 2028 #ifdef ASSERT 2029 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) { 2030 PcDesc* lower = nm->scopes_pcs_begin(); 2031 PcDesc* upper = nm->scopes_pcs_end(); 2032 lower += 1; // exclude initial sentinel 2033 PcDesc* res = NULL; 2034 for (PcDesc* p = lower; p < upper; p++) { 2035 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc 2036 if (match_desc(p, pc_offset, approximate)) { 2037 if (res == NULL) 2038 res = p; 2039 else 2040 res = (PcDesc*) badAddress; 2041 } 2042 } 2043 return res; 2044 } 2045 #endif 2046 2047 2048 // Finds a PcDesc with real-pc equal to "pc" 2049 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) { 2050 address base_address = code_begin(); 2051 if ((pc < base_address) || 2052 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { 2053 return NULL; // PC is wildly out of range 2054 } 2055 int pc_offset = (int) (pc - base_address); 2056 2057 // Check the PcDesc cache if it contains the desired PcDesc 2058 // (This as an almost 100% hit rate.) 2059 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); 2060 if (res != NULL) { 2061 assert(res == linear_search(this, pc_offset, approximate), "cache ok"); 2062 return res; 2063 } 2064 2065 // Fallback algorithm: quasi-linear search for the PcDesc 2066 // Find the last pc_offset less than the given offset. 2067 // The successor must be the required match, if there is a match at all. 2068 // (Use a fixed radix to avoid expensive affine pointer arithmetic.) 2069 PcDesc* lower = scopes_pcs_begin(); 2070 PcDesc* upper = scopes_pcs_end(); 2071 upper -= 1; // exclude final sentinel 2072 if (lower >= upper) return NULL; // native method; no PcDescs at all 2073 2074 #define assert_LU_OK \ 2075 /* invariant on lower..upper during the following search: */ \ 2076 assert(lower->pc_offset() < pc_offset, "sanity"); \ 2077 assert(upper->pc_offset() >= pc_offset, "sanity") 2078 assert_LU_OK; 2079 2080 // Use the last successful return as a split point. 2081 PcDesc* mid = _pc_desc_cache.last_pc_desc(); 2082 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2083 if (mid->pc_offset() < pc_offset) { 2084 lower = mid; 2085 } else { 2086 upper = mid; 2087 } 2088 2089 // Take giant steps at first (4096, then 256, then 16, then 1) 2090 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); 2091 const int RADIX = (1 << LOG2_RADIX); 2092 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { 2093 while ((mid = lower + step) < upper) { 2094 assert_LU_OK; 2095 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2096 if (mid->pc_offset() < pc_offset) { 2097 lower = mid; 2098 } else { 2099 upper = mid; 2100 break; 2101 } 2102 } 2103 assert_LU_OK; 2104 } 2105 2106 // Sneak up on the value with a linear search of length ~16. 2107 while (true) { 2108 assert_LU_OK; 2109 mid = lower + 1; 2110 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2111 if (mid->pc_offset() < pc_offset) { 2112 lower = mid; 2113 } else { 2114 upper = mid; 2115 break; 2116 } 2117 } 2118 #undef assert_LU_OK 2119 2120 if (match_desc(upper, pc_offset, approximate)) { 2121 assert(upper == linear_search(this, pc_offset, approximate), "search ok"); 2122 _pc_desc_cache.add_pc_desc(upper); 2123 return upper; 2124 } else { 2125 assert(NULL == linear_search(this, pc_offset, approximate), "search ok"); 2126 return NULL; 2127 } 2128 } 2129 2130 2131 void nmethod::check_all_dependencies(DepChange& changes) { 2132 // Checked dependencies are allocated into this ResourceMark 2133 ResourceMark rm; 2134 2135 // Turn off dependency tracing while actually testing dependencies. 2136 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) ); 2137 2138 // 'dep_signature_buffers' caches already checked dependencies. 2139 DependencySignatureBuffer dep_signature_buffers; 2140 2141 // Iterate over live nmethods and check dependencies of all nmethods that are not 2142 // marked for deoptimization. A particular dependency is only checked once. 2143 for(nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); nm != NULL; nm = CodeCache::alive_nmethod(CodeCache::next(nm))) { 2144 if (!nm->is_marked_for_deoptimization()) { 2145 for (Dependencies::DepStream deps(nm); deps.next(); ) { 2146 // Construct abstraction of a dependency. 2147 const DependencySignature* current_sig = new DependencySignature(deps); 2148 // Determine if 'deps' is already checked. If it is not checked, 2149 // 'add_if_missing()' adds the dependency signature and returns 2150 // false. 2151 if (!dep_signature_buffers.add_if_missing(*current_sig)) { 2152 if (deps.check_dependency() != NULL) { 2153 // Dependency checking failed. Print out information about the failed 2154 // dependency and finally fail with an assert. We can fail here, since 2155 // dependency checking is never done in a product build. 2156 ResourceMark rm; 2157 changes.print(); 2158 nm->print(); 2159 nm->print_dependencies(); 2160 assert(false, "Should have been marked for deoptimization"); 2161 } 2162 } 2163 } 2164 } 2165 } 2166 } 2167 2168 bool nmethod::check_dependency_on(DepChange& changes) { 2169 // What has happened: 2170 // 1) a new class dependee has been added 2171 // 2) dependee and all its super classes have been marked 2172 bool found_check = false; // set true if we are upset 2173 for (Dependencies::DepStream deps(this); deps.next(); ) { 2174 // Evaluate only relevant dependencies. 2175 if (deps.spot_check_dependency_at(changes) != NULL) { 2176 found_check = true; 2177 NOT_DEBUG(break); 2178 } 2179 } 2180 return found_check; 2181 } 2182 2183 bool nmethod::is_evol_dependent_on(Klass* dependee) { 2184 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee); 2185 Array<Method*>* dependee_methods = dependee_ik->methods(); 2186 for (Dependencies::DepStream deps(this); deps.next(); ) { 2187 if (deps.type() == Dependencies::evol_method) { 2188 Method* method = deps.method_argument(0); 2189 for (int j = 0; j < dependee_methods->length(); j++) { 2190 if (dependee_methods->at(j) == method) { 2191 // RC_TRACE macro has an embedded ResourceMark 2192 RC_TRACE(0x01000000, 2193 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)", 2194 _method->method_holder()->external_name(), 2195 _method->name()->as_C_string(), 2196 _method->signature()->as_C_string(), compile_id(), 2197 method->method_holder()->external_name(), 2198 method->name()->as_C_string(), 2199 method->signature()->as_C_string())); 2200 if (TraceDependencies || LogCompilation) 2201 deps.log_dependency(dependee); 2202 return true; 2203 } 2204 } 2205 } 2206 } 2207 return false; 2208 } 2209 2210 // Called from mark_for_deoptimization, when dependee is invalidated. 2211 bool nmethod::is_dependent_on_method(Method* dependee) { 2212 for (Dependencies::DepStream deps(this); deps.next(); ) { 2213 if (deps.type() != Dependencies::evol_method) 2214 continue; 2215 Method* method = deps.method_argument(0); 2216 if (method == dependee) return true; 2217 } 2218 return false; 2219 } 2220 2221 2222 bool nmethod::is_patchable_at(address instr_addr) { 2223 assert(insts_contains(instr_addr), "wrong nmethod used"); 2224 if (is_zombie()) { 2225 // a zombie may never be patched 2226 return false; 2227 } 2228 return true; 2229 } 2230 2231 2232 address nmethod::continuation_for_implicit_exception(address pc) { 2233 // Exception happened outside inline-cache check code => we are inside 2234 // an active nmethod => use cpc to determine a return address 2235 int exception_offset = pc - code_begin(); 2236 int cont_offset = ImplicitExceptionTable(this).at( exception_offset ); 2237 #ifdef ASSERT 2238 if (cont_offset == 0) { 2239 Thread* thread = ThreadLocalStorage::get_thread_slow(); 2240 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY 2241 HandleMark hm(thread); 2242 ResourceMark rm(thread); 2243 CodeBlob* cb = CodeCache::find_blob(pc); 2244 assert(cb != NULL && cb == this, ""); 2245 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc); 2246 print(); 2247 method()->print_codes(); 2248 print_code(); 2249 print_pcs(); 2250 } 2251 #endif 2252 if (cont_offset == 0) { 2253 // Let the normal error handling report the exception 2254 return NULL; 2255 } 2256 return code_begin() + cont_offset; 2257 } 2258 2259 2260 2261 void nmethod_init() { 2262 // make sure you didn't forget to adjust the filler fields 2263 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word"); 2264 } 2265 2266 2267 //------------------------------------------------------------------------------------------- 2268 2269 2270 // QQQ might we make this work from a frame?? 2271 nmethodLocker::nmethodLocker(address pc) { 2272 CodeBlob* cb = CodeCache::find_blob(pc); 2273 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found"); 2274 _nm = (nmethod*)cb; 2275 lock_nmethod(_nm); 2276 } 2277 2278 // Only JvmtiDeferredEvent::compiled_method_unload_event() 2279 // should pass zombie_ok == true. 2280 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) { 2281 if (nm == NULL) return; 2282 Atomic::inc(&nm->_lock_count); 2283 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method"); 2284 } 2285 2286 void nmethodLocker::unlock_nmethod(nmethod* nm) { 2287 if (nm == NULL) return; 2288 Atomic::dec(&nm->_lock_count); 2289 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock"); 2290 } 2291 2292 2293 // ----------------------------------------------------------------------------- 2294 // nmethod::get_deopt_original_pc 2295 // 2296 // Return the original PC for the given PC if: 2297 // (a) the given PC belongs to a nmethod and 2298 // (b) it is a deopt PC 2299 address nmethod::get_deopt_original_pc(const frame* fr) { 2300 if (fr->cb() == NULL) return NULL; 2301 2302 nmethod* nm = fr->cb()->as_nmethod_or_null(); 2303 if (nm != NULL && nm->is_deopt_pc(fr->pc())) 2304 return nm->get_original_pc(fr); 2305 2306 return NULL; 2307 } 2308 2309 2310 // ----------------------------------------------------------------------------- 2311 // MethodHandle 2312 2313 bool nmethod::is_method_handle_return(address return_pc) { 2314 if (!has_method_handle_invokes()) return false; 2315 PcDesc* pd = pc_desc_at(return_pc); 2316 if (pd == NULL) 2317 return false; 2318 return pd->is_method_handle_invoke(); 2319 } 2320 2321 2322 // ----------------------------------------------------------------------------- 2323 // Verification 2324 2325 class VerifyOopsClosure: public OopClosure { 2326 nmethod* _nm; 2327 bool _ok; 2328 public: 2329 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } 2330 bool ok() { return _ok; } 2331 virtual void do_oop(oop* p) { 2332 if ((*p) == NULL || (*p)->is_oop()) return; 2333 if (_ok) { 2334 _nm->print_nmethod(true); 2335 _ok = false; 2336 } 2337 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2338 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2339 } 2340 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2341 }; 2342 2343 void nmethod::verify() { 2344 2345 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant 2346 // seems odd. 2347 2348 if( is_zombie() || is_not_entrant() ) 2349 return; 2350 2351 // Make sure all the entry points are correctly aligned for patching. 2352 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point()); 2353 2354 // assert(method()->is_oop(), "must be valid"); 2355 2356 ResourceMark rm; 2357 2358 if (!CodeCache::contains(this)) { 2359 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this)); 2360 } 2361 2362 if(is_native_method() ) 2363 return; 2364 2365 nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); 2366 if (nm != this) { 2367 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", 2368 this)); 2369 } 2370 2371 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2372 if (! p->verify(this)) { 2373 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this); 2374 } 2375 } 2376 2377 VerifyOopsClosure voc(this); 2378 oops_do(&voc); 2379 assert(voc.ok(), "embedded oops must be OK"); 2380 verify_scavenge_root_oops(); 2381 2382 verify_scopes(); 2383 } 2384 2385 2386 void nmethod::verify_interrupt_point(address call_site) { 2387 // Verify IC only when nmethod installation is finished. 2388 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed 2389 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state 2390 if (is_installed) { 2391 Thread *cur = Thread::current(); 2392 if (CompiledIC_lock->owner() == cur || 2393 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) && 2394 SafepointSynchronize::is_at_safepoint())) { 2395 CompiledIC_at(this, call_site); 2396 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 2397 } else { 2398 MutexLocker ml_verify (CompiledIC_lock); 2399 CompiledIC_at(this, call_site); 2400 } 2401 } 2402 2403 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address()); 2404 assert(pd != NULL, "PcDesc must exist"); 2405 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(), 2406 pd->obj_decode_offset(), pd->should_reexecute(), 2407 pd->return_oop()); 2408 !sd->is_top(); sd = sd->sender()) { 2409 sd->verify(); 2410 } 2411 } 2412 2413 void nmethod::verify_scopes() { 2414 if( !method() ) return; // Runtime stubs have no scope 2415 if (method()->is_native()) return; // Ignore stub methods. 2416 // iterate through all interrupt point 2417 // and verify the debug information is valid. 2418 RelocIterator iter((nmethod*)this); 2419 while (iter.next()) { 2420 address stub = NULL; 2421 switch (iter.type()) { 2422 case relocInfo::virtual_call_type: 2423 verify_interrupt_point(iter.addr()); 2424 break; 2425 case relocInfo::opt_virtual_call_type: 2426 stub = iter.opt_virtual_call_reloc()->static_stub(); 2427 verify_interrupt_point(iter.addr()); 2428 break; 2429 case relocInfo::static_call_type: 2430 stub = iter.static_call_reloc()->static_stub(); 2431 //verify_interrupt_point(iter.addr()); 2432 break; 2433 case relocInfo::runtime_call_type: 2434 address destination = iter.reloc()->value(); 2435 // Right now there is no way to find out which entries support 2436 // an interrupt point. It would be nice if we had this 2437 // information in a table. 2438 break; 2439 } 2440 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section"); 2441 } 2442 } 2443 2444 2445 // ----------------------------------------------------------------------------- 2446 // Non-product code 2447 #ifndef PRODUCT 2448 2449 class DebugScavengeRoot: public OopClosure { 2450 nmethod* _nm; 2451 bool _ok; 2452 public: 2453 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { } 2454 bool ok() { return _ok; } 2455 virtual void do_oop(oop* p) { 2456 if ((*p) == NULL || !(*p)->is_scavengable()) return; 2457 if (_ok) { 2458 _nm->print_nmethod(true); 2459 _ok = false; 2460 } 2461 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2462 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2463 (*p)->print(); 2464 } 2465 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2466 }; 2467 2468 void nmethod::verify_scavenge_root_oops() { 2469 if (!on_scavenge_root_list()) { 2470 // Actually look inside, to verify the claim that it's clean. 2471 DebugScavengeRoot debug_scavenge_root(this); 2472 oops_do(&debug_scavenge_root); 2473 if (!debug_scavenge_root.ok()) 2474 fatal("found an unadvertised bad scavengable oop in the code cache"); 2475 } 2476 assert(scavenge_root_not_marked(), ""); 2477 } 2478 2479 #endif // PRODUCT 2480 2481 // Printing operations 2482 2483 void nmethod::print() const { 2484 ResourceMark rm; 2485 ttyLocker ttyl; // keep the following output all in one block 2486 2487 tty->print("Compiled method "); 2488 2489 if (is_compiled_by_c1()) { 2490 tty->print("(c1) "); 2491 } else if (is_compiled_by_c2()) { 2492 tty->print("(c2) "); 2493 } else if (is_compiled_by_shark()) { 2494 tty->print("(shark) "); 2495 } else { 2496 tty->print("(nm) "); 2497 } 2498 2499 print_on(tty, NULL); 2500 2501 if (WizardMode) { 2502 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this); 2503 tty->print(" for method " INTPTR_FORMAT , (address)method()); 2504 tty->print(" { "); 2505 if (is_in_use()) tty->print("in_use "); 2506 if (is_not_entrant()) tty->print("not_entrant "); 2507 if (is_zombie()) tty->print("zombie "); 2508 if (is_unloaded()) tty->print("unloaded "); 2509 if (on_scavenge_root_list()) tty->print("scavenge_root "); 2510 tty->print_cr("}:"); 2511 } 2512 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2513 (address)this, 2514 (address)this + size(), 2515 size()); 2516 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2517 relocation_begin(), 2518 relocation_end(), 2519 relocation_size()); 2520 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2521 consts_begin(), 2522 consts_end(), 2523 consts_size()); 2524 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2525 insts_begin(), 2526 insts_end(), 2527 insts_size()); 2528 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2529 stub_begin(), 2530 stub_end(), 2531 stub_size()); 2532 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2533 oops_begin(), 2534 oops_end(), 2535 oops_size()); 2536 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2537 metadata_begin(), 2538 metadata_end(), 2539 metadata_size()); 2540 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2541 scopes_data_begin(), 2542 scopes_data_end(), 2543 scopes_data_size()); 2544 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2545 scopes_pcs_begin(), 2546 scopes_pcs_end(), 2547 scopes_pcs_size()); 2548 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2549 dependencies_begin(), 2550 dependencies_end(), 2551 dependencies_size()); 2552 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2553 handler_table_begin(), 2554 handler_table_end(), 2555 handler_table_size()); 2556 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2557 nul_chk_table_begin(), 2558 nul_chk_table_end(), 2559 nul_chk_table_size()); 2560 } 2561 2562 void nmethod::print_code() { 2563 HandleMark hm; 2564 ResourceMark m; 2565 Disassembler::decode(this); 2566 } 2567 2568 2569 #ifndef PRODUCT 2570 2571 void nmethod::print_scopes() { 2572 // Find the first pc desc for all scopes in the code and print it. 2573 ResourceMark rm; 2574 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2575 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) 2576 continue; 2577 2578 ScopeDesc* sd = scope_desc_at(p->real_pc(this)); 2579 sd->print_on(tty, p); 2580 } 2581 } 2582 2583 void nmethod::print_dependencies() { 2584 ResourceMark rm; 2585 ttyLocker ttyl; // keep the following output all in one block 2586 tty->print_cr("Dependencies:"); 2587 for (Dependencies::DepStream deps(this); deps.next(); ) { 2588 deps.print_dependency(); 2589 Klass* ctxk = deps.context_type(); 2590 if (ctxk != NULL) { 2591 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) { 2592 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name()); 2593 } 2594 } 2595 deps.log_dependency(); // put it into the xml log also 2596 } 2597 } 2598 2599 2600 void nmethod::print_relocations() { 2601 ResourceMark m; // in case methods get printed via the debugger 2602 tty->print_cr("relocations:"); 2603 RelocIterator iter(this); 2604 iter.print(); 2605 if (UseRelocIndex) { 2606 jint* index_end = (jint*)relocation_end() - 1; 2607 jint index_size = *index_end; 2608 jint* index_start = (jint*)( (address)index_end - index_size ); 2609 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size); 2610 if (index_size > 0) { 2611 jint* ip; 2612 for (ip = index_start; ip+2 <= index_end; ip += 2) 2613 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT, 2614 ip[0], 2615 ip[1], 2616 header_end()+ip[0], 2617 relocation_begin()-1+ip[1]); 2618 for (; ip < index_end; ip++) 2619 tty->print_cr(" (%d ?)", ip[0]); 2620 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip); 2621 ip++; 2622 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip); 2623 } 2624 } 2625 } 2626 2627 2628 void nmethod::print_pcs() { 2629 ResourceMark m; // in case methods get printed via debugger 2630 tty->print_cr("pc-bytecode offsets:"); 2631 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2632 p->print(this); 2633 } 2634 } 2635 2636 #endif // PRODUCT 2637 2638 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) { 2639 RelocIterator iter(this, begin, end); 2640 bool have_one = false; 2641 while (iter.next()) { 2642 have_one = true; 2643 switch (iter.type()) { 2644 case relocInfo::none: return "no_reloc"; 2645 case relocInfo::oop_type: { 2646 stringStream st; 2647 oop_Relocation* r = iter.oop_reloc(); 2648 oop obj = r->oop_value(); 2649 st.print("oop("); 2650 if (obj == NULL) st.print("NULL"); 2651 else obj->print_value_on(&st); 2652 st.print(")"); 2653 return st.as_string(); 2654 } 2655 case relocInfo::metadata_type: { 2656 stringStream st; 2657 metadata_Relocation* r = iter.metadata_reloc(); 2658 Metadata* obj = r->metadata_value(); 2659 st.print("metadata("); 2660 if (obj == NULL) st.print("NULL"); 2661 else obj->print_value_on(&st); 2662 st.print(")"); 2663 return st.as_string(); 2664 } 2665 case relocInfo::virtual_call_type: return "virtual_call"; 2666 case relocInfo::opt_virtual_call_type: return "optimized virtual_call"; 2667 case relocInfo::static_call_type: return "static_call"; 2668 case relocInfo::static_stub_type: return "static_stub"; 2669 case relocInfo::runtime_call_type: return "runtime_call"; 2670 case relocInfo::external_word_type: return "external_word"; 2671 case relocInfo::internal_word_type: return "internal_word"; 2672 case relocInfo::section_word_type: return "section_word"; 2673 case relocInfo::poll_type: return "poll"; 2674 case relocInfo::poll_return_type: return "poll_return"; 2675 case relocInfo::type_mask: return "type_bit_mask"; 2676 } 2677 } 2678 return have_one ? "other" : NULL; 2679 } 2680 2681 // Return a the last scope in (begin..end] 2682 ScopeDesc* nmethod::scope_desc_in(address begin, address end) { 2683 PcDesc* p = pc_desc_near(begin+1); 2684 if (p != NULL && p->real_pc(this) <= end) { 2685 return new ScopeDesc(this, p->scope_decode_offset(), 2686 p->obj_decode_offset(), p->should_reexecute(), 2687 p->return_oop()); 2688 } 2689 return NULL; 2690 } 2691 2692 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const { 2693 if (block_begin == entry_point()) stream->print_cr("[Entry Point]"); 2694 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]"); 2695 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]"); 2696 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]"); 2697 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]"); 2698 2699 if (has_method_handle_invokes()) 2700 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]"); 2701 2702 if (block_begin == consts_begin()) stream->print_cr("[Constants]"); 2703 2704 if (block_begin == entry_point()) { 2705 methodHandle m = method(); 2706 if (m.not_null()) { 2707 stream->print(" # "); 2708 m->print_value_on(stream); 2709 stream->cr(); 2710 } 2711 if (m.not_null() && !is_osr_method()) { 2712 ResourceMark rm; 2713 int sizeargs = m->size_of_parameters(); 2714 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs); 2715 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs); 2716 { 2717 int sig_index = 0; 2718 if (!m->is_static()) 2719 sig_bt[sig_index++] = T_OBJECT; // 'this' 2720 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) { 2721 BasicType t = ss.type(); 2722 sig_bt[sig_index++] = t; 2723 if (type2size[t] == 2) { 2724 sig_bt[sig_index++] = T_VOID; 2725 } else { 2726 assert(type2size[t] == 1, "size is 1 or 2"); 2727 } 2728 } 2729 assert(sig_index == sizeargs, ""); 2730 } 2731 const char* spname = "sp"; // make arch-specific? 2732 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false); 2733 int stack_slot_offset = this->frame_size() * wordSize; 2734 int tab1 = 14, tab2 = 24; 2735 int sig_index = 0; 2736 int arg_index = (m->is_static() ? 0 : -1); 2737 bool did_old_sp = false; 2738 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) { 2739 bool at_this = (arg_index == -1); 2740 bool at_old_sp = false; 2741 BasicType t = (at_this ? T_OBJECT : ss.type()); 2742 assert(t == sig_bt[sig_index], "sigs in sync"); 2743 if (at_this) 2744 stream->print(" # this: "); 2745 else 2746 stream->print(" # parm%d: ", arg_index); 2747 stream->move_to(tab1); 2748 VMReg fst = regs[sig_index].first(); 2749 VMReg snd = regs[sig_index].second(); 2750 if (fst->is_reg()) { 2751 stream->print("%s", fst->name()); 2752 if (snd->is_valid()) { 2753 stream->print(":%s", snd->name()); 2754 } 2755 } else if (fst->is_stack()) { 2756 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset; 2757 if (offset == stack_slot_offset) at_old_sp = true; 2758 stream->print("[%s+0x%x]", spname, offset); 2759 } else { 2760 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd); 2761 } 2762 stream->print(" "); 2763 stream->move_to(tab2); 2764 stream->print("= "); 2765 if (at_this) { 2766 m->method_holder()->print_value_on(stream); 2767 } else { 2768 bool did_name = false; 2769 if (!at_this && ss.is_object()) { 2770 Symbol* name = ss.as_symbol_or_null(); 2771 if (name != NULL) { 2772 name->print_value_on(stream); 2773 did_name = true; 2774 } 2775 } 2776 if (!did_name) 2777 stream->print("%s", type2name(t)); 2778 } 2779 if (at_old_sp) { 2780 stream->print(" (%s of caller)", spname); 2781 did_old_sp = true; 2782 } 2783 stream->cr(); 2784 sig_index += type2size[t]; 2785 arg_index += 1; 2786 if (!at_this) ss.next(); 2787 } 2788 if (!did_old_sp) { 2789 stream->print(" # "); 2790 stream->move_to(tab1); 2791 stream->print("[%s+0x%x]", spname, stack_slot_offset); 2792 stream->print(" (%s of caller)", spname); 2793 stream->cr(); 2794 } 2795 } 2796 } 2797 } 2798 2799 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) { 2800 // First, find an oopmap in (begin, end]. 2801 // We use the odd half-closed interval so that oop maps and scope descs 2802 // which are tied to the byte after a call are printed with the call itself. 2803 address base = code_begin(); 2804 OopMapSet* oms = oop_maps(); 2805 if (oms != NULL) { 2806 for (int i = 0, imax = oms->size(); i < imax; i++) { 2807 OopMap* om = oms->at(i); 2808 address pc = base + om->offset(); 2809 if (pc > begin) { 2810 if (pc <= end) { 2811 st->move_to(column); 2812 st->print("; "); 2813 om->print_on(st); 2814 } 2815 break; 2816 } 2817 } 2818 } 2819 2820 // Print any debug info present at this pc. 2821 ScopeDesc* sd = scope_desc_in(begin, end); 2822 if (sd != NULL) { 2823 st->move_to(column); 2824 if (sd->bci() == SynchronizationEntryBCI) { 2825 st->print(";*synchronization entry"); 2826 } else { 2827 if (sd->method() == NULL) { 2828 st->print("method is NULL"); 2829 } else if (sd->method()->is_native()) { 2830 st->print("method is native"); 2831 } else { 2832 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci()); 2833 st->print(";*%s", Bytecodes::name(bc)); 2834 switch (bc) { 2835 case Bytecodes::_invokevirtual: 2836 case Bytecodes::_invokespecial: 2837 case Bytecodes::_invokestatic: 2838 case Bytecodes::_invokeinterface: 2839 { 2840 Bytecode_invoke invoke(sd->method(), sd->bci()); 2841 st->print(" "); 2842 if (invoke.name() != NULL) 2843 invoke.name()->print_symbol_on(st); 2844 else 2845 st->print("<UNKNOWN>"); 2846 break; 2847 } 2848 case Bytecodes::_getfield: 2849 case Bytecodes::_putfield: 2850 case Bytecodes::_getstatic: 2851 case Bytecodes::_putstatic: 2852 { 2853 Bytecode_field field(sd->method(), sd->bci()); 2854 st->print(" "); 2855 if (field.name() != NULL) 2856 field.name()->print_symbol_on(st); 2857 else 2858 st->print("<UNKNOWN>"); 2859 } 2860 } 2861 } 2862 } 2863 2864 // Print all scopes 2865 for (;sd != NULL; sd = sd->sender()) { 2866 st->move_to(column); 2867 st->print("; -"); 2868 if (sd->method() == NULL) { 2869 st->print("method is NULL"); 2870 } else { 2871 sd->method()->print_short_name(st); 2872 } 2873 int lineno = sd->method()->line_number_from_bci(sd->bci()); 2874 if (lineno != -1) { 2875 st->print("@%d (line %d)", sd->bci(), lineno); 2876 } else { 2877 st->print("@%d", sd->bci()); 2878 } 2879 st->cr(); 2880 } 2881 } 2882 2883 // Print relocation information 2884 const char* str = reloc_string_for(begin, end); 2885 if (str != NULL) { 2886 if (sd != NULL) st->cr(); 2887 st->move_to(column); 2888 st->print("; {%s}", str); 2889 } 2890 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin()); 2891 if (cont_offset != 0) { 2892 st->move_to(column); 2893 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset); 2894 } 2895 2896 } 2897 2898 #ifndef PRODUCT 2899 2900 void nmethod::print_value_on(outputStream* st) const { 2901 st->print("nmethod"); 2902 print_on(st, NULL); 2903 } 2904 2905 void nmethod::print_calls(outputStream* st) { 2906 RelocIterator iter(this); 2907 while (iter.next()) { 2908 switch (iter.type()) { 2909 case relocInfo::virtual_call_type: 2910 case relocInfo::opt_virtual_call_type: { 2911 VerifyMutexLocker mc(CompiledIC_lock); 2912 CompiledIC_at(iter.reloc())->print(); 2913 break; 2914 } 2915 case relocInfo::static_call_type: 2916 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr()); 2917 compiledStaticCall_at(iter.reloc())->print(); 2918 break; 2919 } 2920 } 2921 } 2922 2923 void nmethod::print_handler_table() { 2924 ExceptionHandlerTable(this).print(); 2925 } 2926 2927 void nmethod::print_nul_chk_table() { 2928 ImplicitExceptionTable(this).print(code_begin()); 2929 } 2930 2931 void nmethod::print_statistics() { 2932 ttyLocker ttyl; 2933 if (xtty != NULL) xtty->head("statistics type='nmethod'"); 2934 nmethod_stats.print_native_nmethod_stats(); 2935 nmethod_stats.print_nmethod_stats(); 2936 DebugInformationRecorder::print_statistics(); 2937 nmethod_stats.print_pc_stats(); 2938 Dependencies::print_statistics(); 2939 if (xtty != NULL) xtty->tail("statistics"); 2940 } 2941 2942 #endif // PRODUCT