1 /* 2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "code/codeCache.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/dependencies.hpp" 29 #include "code/nmethod.hpp" 30 #include "code/scopeDesc.hpp" 31 #include "compiler/abstractCompiler.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "compiler/compileLog.hpp" 34 #include "compiler/compilerOracle.hpp" 35 #include "compiler/disassembler.hpp" 36 #include "interpreter/bytecode.hpp" 37 #include "oops/methodData.hpp" 38 #include "prims/jvmtiRedefineClassesTrace.hpp" 39 #include "prims/jvmtiImpl.hpp" 40 #include "runtime/sharedRuntime.hpp" 41 #include "runtime/sweeper.hpp" 42 #include "utilities/dtrace.hpp" 43 #include "utilities/events.hpp" 44 #include "utilities/xmlstream.hpp" 45 #ifdef SHARK 46 #include "shark/sharkCompiler.hpp" 47 #endif 48 49 #ifdef DTRACE_ENABLED 50 51 // Only bother with this argument setup if dtrace is available 52 53 #ifndef USDT2 54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load, 55 const char*, int, const char*, int, const char*, int, void*, size_t); 56 57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload, 58 char*, int, char*, int, char*, int); 59 60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 61 { \ 62 Method* m = (method); \ 63 if (m != NULL) { \ 64 Symbol* klass_name = m->klass_name(); \ 65 Symbol* name = m->name(); \ 66 Symbol* signature = m->signature(); \ 67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \ 68 klass_name->bytes(), klass_name->utf8_length(), \ 69 name->bytes(), name->utf8_length(), \ 70 signature->bytes(), signature->utf8_length()); \ 71 } \ 72 } 73 #else /* USDT2 */ 74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 75 { \ 76 Method* m = (method); \ 77 if (m != NULL) { \ 78 Symbol* klass_name = m->klass_name(); \ 79 Symbol* name = m->name(); \ 80 Symbol* signature = m->signature(); \ 81 HOTSPOT_COMPILED_METHOD_UNLOAD( \ 82 (char *) klass_name->bytes(), klass_name->utf8_length(), \ 83 (char *) name->bytes(), name->utf8_length(), \ 84 (char *) signature->bytes(), signature->utf8_length()); \ 85 } \ 86 } 87 #endif /* USDT2 */ 88 89 #else // ndef DTRACE_ENABLED 90 91 #define DTRACE_METHOD_UNLOAD_PROBE(method) 92 93 #endif 94 95 bool nmethod::is_compiled_by_c1() const { 96 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing 97 if (is_native_method()) return false; 98 return compiler()->is_c1(); 99 } 100 bool nmethod::is_compiled_by_c2() const { 101 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing 102 if (is_native_method()) return false; 103 return compiler()->is_c2(); 104 } 105 bool nmethod::is_compiled_by_shark() const { 106 if (is_native_method()) return false; 107 assert(compiler() != NULL, "must be"); 108 return compiler()->is_shark(); 109 } 110 111 112 113 //--------------------------------------------------------------------------------- 114 // NMethod statistics 115 // They are printed under various flags, including: 116 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation. 117 // (In the latter two cases, they like other stats are printed to the log only.) 118 119 #ifndef PRODUCT 120 // These variables are put into one block to reduce relocations 121 // and make it simpler to print from the debugger. 122 static 123 struct nmethod_stats_struct { 124 int nmethod_count; 125 int total_size; 126 int relocation_size; 127 int consts_size; 128 int insts_size; 129 int stub_size; 130 int scopes_data_size; 131 int scopes_pcs_size; 132 int dependencies_size; 133 int handler_table_size; 134 int nul_chk_table_size; 135 int oops_size; 136 137 void note_nmethod(nmethod* nm) { 138 nmethod_count += 1; 139 total_size += nm->size(); 140 relocation_size += nm->relocation_size(); 141 consts_size += nm->consts_size(); 142 insts_size += nm->insts_size(); 143 stub_size += nm->stub_size(); 144 oops_size += nm->oops_size(); 145 scopes_data_size += nm->scopes_data_size(); 146 scopes_pcs_size += nm->scopes_pcs_size(); 147 dependencies_size += nm->dependencies_size(); 148 handler_table_size += nm->handler_table_size(); 149 nul_chk_table_size += nm->nul_chk_table_size(); 150 } 151 void print_nmethod_stats() { 152 if (nmethod_count == 0) return; 153 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count); 154 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size); 155 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size); 156 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size); 157 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size); 158 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size); 159 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size); 160 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size); 161 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size); 162 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size); 163 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size); 164 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size); 165 } 166 167 int native_nmethod_count; 168 int native_total_size; 169 int native_relocation_size; 170 int native_insts_size; 171 int native_oops_size; 172 void note_native_nmethod(nmethod* nm) { 173 native_nmethod_count += 1; 174 native_total_size += nm->size(); 175 native_relocation_size += nm->relocation_size(); 176 native_insts_size += nm->insts_size(); 177 native_oops_size += nm->oops_size(); 178 } 179 void print_native_nmethod_stats() { 180 if (native_nmethod_count == 0) return; 181 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count); 182 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size); 183 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size); 184 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size); 185 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size); 186 } 187 188 int pc_desc_resets; // number of resets (= number of caches) 189 int pc_desc_queries; // queries to nmethod::find_pc_desc 190 int pc_desc_approx; // number of those which have approximate true 191 int pc_desc_repeats; // number of _pc_descs[0] hits 192 int pc_desc_hits; // number of LRU cache hits 193 int pc_desc_tests; // total number of PcDesc examinations 194 int pc_desc_searches; // total number of quasi-binary search steps 195 int pc_desc_adds; // number of LUR cache insertions 196 197 void print_pc_stats() { 198 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query", 199 pc_desc_queries, 200 (double)(pc_desc_tests + pc_desc_searches) 201 / pc_desc_queries); 202 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d", 203 pc_desc_resets, 204 pc_desc_queries, pc_desc_approx, 205 pc_desc_repeats, pc_desc_hits, 206 pc_desc_tests, pc_desc_searches, pc_desc_adds); 207 } 208 } nmethod_stats; 209 #endif //PRODUCT 210 211 212 //--------------------------------------------------------------------------------- 213 214 215 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) { 216 assert(pc != NULL, "Must be non null"); 217 assert(exception.not_null(), "Must be non null"); 218 assert(handler != NULL, "Must be non null"); 219 220 _count = 0; 221 _exception_type = exception->klass(); 222 _next = NULL; 223 224 add_address_and_handler(pc,handler); 225 } 226 227 228 address ExceptionCache::match(Handle exception, address pc) { 229 assert(pc != NULL,"Must be non null"); 230 assert(exception.not_null(),"Must be non null"); 231 if (exception->klass() == exception_type()) { 232 return (test_address(pc)); 233 } 234 235 return NULL; 236 } 237 238 239 bool ExceptionCache::match_exception_with_space(Handle exception) { 240 assert(exception.not_null(),"Must be non null"); 241 if (exception->klass() == exception_type() && count() < cache_size) { 242 return true; 243 } 244 return false; 245 } 246 247 248 address ExceptionCache::test_address(address addr) { 249 for (int i=0; i<count(); i++) { 250 if (pc_at(i) == addr) { 251 return handler_at(i); 252 } 253 } 254 return NULL; 255 } 256 257 258 bool ExceptionCache::add_address_and_handler(address addr, address handler) { 259 if (test_address(addr) == handler) return true; 260 if (count() < cache_size) { 261 set_pc_at(count(),addr); 262 set_handler_at(count(), handler); 263 increment_count(); 264 return true; 265 } 266 return false; 267 } 268 269 270 // private method for handling exception cache 271 // These methods are private, and used to manipulate the exception cache 272 // directly. 273 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) { 274 ExceptionCache* ec = exception_cache(); 275 while (ec != NULL) { 276 if (ec->match_exception_with_space(exception)) { 277 return ec; 278 } 279 ec = ec->next(); 280 } 281 return NULL; 282 } 283 284 285 //----------------------------------------------------------------------------- 286 287 288 // Helper used by both find_pc_desc methods. 289 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) { 290 NOT_PRODUCT(++nmethod_stats.pc_desc_tests); 291 if (!approximate) 292 return pc->pc_offset() == pc_offset; 293 else 294 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset(); 295 } 296 297 void PcDescCache::reset_to(PcDesc* initial_pc_desc) { 298 if (initial_pc_desc == NULL) { 299 _pc_descs[0] = NULL; // native method; no PcDescs at all 300 return; 301 } 302 NOT_PRODUCT(++nmethod_stats.pc_desc_resets); 303 // reset the cache by filling it with benign (non-null) values 304 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel"); 305 for (int i = 0; i < cache_size; i++) 306 _pc_descs[i] = initial_pc_desc; 307 } 308 309 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) { 310 NOT_PRODUCT(++nmethod_stats.pc_desc_queries); 311 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx); 312 313 // Note: one might think that caching the most recently 314 // read value separately would be a win, but one would be 315 // wrong. When many threads are updating it, the cache 316 // line it's in would bounce between caches, negating 317 // any benefit. 318 319 // In order to prevent race conditions do not load cache elements 320 // repeatedly, but use a local copy: 321 PcDesc* res; 322 323 // Step one: Check the most recently added value. 324 res = _pc_descs[0]; 325 if (res == NULL) return NULL; // native method; no PcDescs at all 326 if (match_desc(res, pc_offset, approximate)) { 327 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats); 328 return res; 329 } 330 331 // Step two: Check the rest of the LRU cache. 332 for (int i = 1; i < cache_size; ++i) { 333 res = _pc_descs[i]; 334 if (res->pc_offset() < 0) break; // optimization: skip empty cache 335 if (match_desc(res, pc_offset, approximate)) { 336 NOT_PRODUCT(++nmethod_stats.pc_desc_hits); 337 return res; 338 } 339 } 340 341 // Report failure. 342 return NULL; 343 } 344 345 void PcDescCache::add_pc_desc(PcDesc* pc_desc) { 346 NOT_PRODUCT(++nmethod_stats.pc_desc_adds); 347 // Update the LRU cache by shifting pc_desc forward. 348 for (int i = 0; i < cache_size; i++) { 349 PcDesc* next = _pc_descs[i]; 350 _pc_descs[i] = pc_desc; 351 pc_desc = next; 352 } 353 } 354 355 // adjust pcs_size so that it is a multiple of both oopSize and 356 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple 357 // of oopSize, then 2*sizeof(PcDesc) is) 358 static int adjust_pcs_size(int pcs_size) { 359 int nsize = round_to(pcs_size, oopSize); 360 if ((nsize % sizeof(PcDesc)) != 0) { 361 nsize = pcs_size + sizeof(PcDesc); 362 } 363 assert((nsize % oopSize) == 0, "correct alignment"); 364 return nsize; 365 } 366 367 //----------------------------------------------------------------------------- 368 369 370 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) { 371 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock"); 372 assert(new_entry != NULL,"Must be non null"); 373 assert(new_entry->next() == NULL, "Must be null"); 374 375 if (exception_cache() != NULL) { 376 new_entry->set_next(exception_cache()); 377 } 378 set_exception_cache(new_entry); 379 } 380 381 void nmethod::remove_from_exception_cache(ExceptionCache* ec) { 382 ExceptionCache* prev = NULL; 383 ExceptionCache* curr = exception_cache(); 384 assert(curr != NULL, "nothing to remove"); 385 // find the previous and next entry of ec 386 while (curr != ec) { 387 prev = curr; 388 curr = curr->next(); 389 assert(curr != NULL, "ExceptionCache not found"); 390 } 391 // now: curr == ec 392 ExceptionCache* next = curr->next(); 393 if (prev == NULL) { 394 set_exception_cache(next); 395 } else { 396 prev->set_next(next); 397 } 398 delete curr; 399 } 400 401 402 // public method for accessing the exception cache 403 // These are the public access methods. 404 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) { 405 // We never grab a lock to read the exception cache, so we may 406 // have false negatives. This is okay, as it can only happen during 407 // the first few exception lookups for a given nmethod. 408 ExceptionCache* ec = exception_cache(); 409 while (ec != NULL) { 410 address ret_val; 411 if ((ret_val = ec->match(exception,pc)) != NULL) { 412 return ret_val; 413 } 414 ec = ec->next(); 415 } 416 return NULL; 417 } 418 419 420 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) { 421 // There are potential race conditions during exception cache updates, so we 422 // must own the ExceptionCache_lock before doing ANY modifications. Because 423 // we don't lock during reads, it is possible to have several threads attempt 424 // to update the cache with the same data. We need to check for already inserted 425 // copies of the current data before adding it. 426 427 MutexLocker ml(ExceptionCache_lock); 428 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception); 429 430 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) { 431 target_entry = new ExceptionCache(exception,pc,handler); 432 add_exception_cache_entry(target_entry); 433 } 434 } 435 436 437 //-------------end of code for ExceptionCache-------------- 438 439 440 int nmethod::total_size() const { 441 return 442 consts_size() + 443 insts_size() + 444 stub_size() + 445 scopes_data_size() + 446 scopes_pcs_size() + 447 handler_table_size() + 448 nul_chk_table_size(); 449 } 450 451 const char* nmethod::compile_kind() const { 452 if (is_osr_method()) return "osr"; 453 if (method() != NULL && is_native_method()) return "c2n"; 454 return NULL; 455 } 456 457 // Fill in default values for various flag fields 458 void nmethod::init_defaults() { 459 _state = alive; 460 _marked_for_reclamation = 0; 461 _has_flushed_dependencies = 0; 462 _speculatively_disconnected = 0; 463 _has_unsafe_access = 0; 464 _has_method_handle_invokes = 0; 465 _lazy_critical_native = 0; 466 _marked_for_deoptimization = 0; 467 _lock_count = 0; 468 _stack_traversal_mark = 0; 469 _unload_reported = false; // jvmti state 470 471 #ifdef ASSERT 472 _oops_are_stale = false; 473 #endif 474 475 _oops_do_mark_link = NULL; 476 _jmethod_id = NULL; 477 _osr_link = NULL; 478 _scavenge_root_link = NULL; 479 _scavenge_root_state = 0; 480 _saved_nmethod_link = NULL; 481 _compiler = NULL; 482 483 #ifdef HAVE_DTRACE_H 484 _trap_offset = 0; 485 #endif // def HAVE_DTRACE_H 486 } 487 488 489 nmethod* nmethod::new_native_nmethod(methodHandle method, 490 int compile_id, 491 CodeBuffer *code_buffer, 492 int vep_offset, 493 int frame_complete, 494 int frame_size, 495 ByteSize basic_lock_owner_sp_offset, 496 ByteSize basic_lock_sp_offset, 497 OopMapSet* oop_maps) { 498 code_buffer->finalize_oop_references(method); 499 // create nmethod 500 nmethod* nm = NULL; 501 { 502 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 503 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 504 CodeOffsets offsets; 505 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 506 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 507 nm = new (native_nmethod_size) 508 nmethod(method(), native_nmethod_size, compile_id, &offsets, 509 code_buffer, frame_size, 510 basic_lock_owner_sp_offset, basic_lock_sp_offset, 511 oop_maps); 512 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm)); 513 if (PrintAssembly && nm != NULL) 514 Disassembler::decode(nm); 515 } 516 // verify nmethod 517 debug_only(if (nm) nm->verify();) // might block 518 519 if (nm != NULL) { 520 nm->log_new_nmethod(); 521 } 522 523 return nm; 524 } 525 526 #ifdef HAVE_DTRACE_H 527 nmethod* nmethod::new_dtrace_nmethod(methodHandle method, 528 CodeBuffer *code_buffer, 529 int vep_offset, 530 int trap_offset, 531 int frame_complete, 532 int frame_size) { 533 code_buffer->finalize_oop_references(method); 534 // create nmethod 535 nmethod* nm = NULL; 536 { 537 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 538 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 539 CodeOffsets offsets; 540 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 541 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset); 542 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 543 544 nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size); 545 546 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); 547 if (PrintAssembly && nm != NULL) 548 Disassembler::decode(nm); 549 } 550 // verify nmethod 551 debug_only(if (nm) nm->verify();) // might block 552 553 if (nm != NULL) { 554 nm->log_new_nmethod(); 555 } 556 557 return nm; 558 } 559 560 #endif // def HAVE_DTRACE_H 561 562 nmethod* nmethod::new_nmethod(methodHandle method, 563 int compile_id, 564 int entry_bci, 565 CodeOffsets* offsets, 566 int orig_pc_offset, 567 DebugInformationRecorder* debug_info, 568 Dependencies* dependencies, 569 CodeBuffer* code_buffer, int frame_size, 570 OopMapSet* oop_maps, 571 ExceptionHandlerTable* handler_table, 572 ImplicitExceptionTable* nul_chk_table, 573 AbstractCompiler* compiler, 574 int comp_level 575 ) 576 { 577 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 578 code_buffer->finalize_oop_references(method); 579 // create nmethod 580 nmethod* nm = NULL; 581 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 582 int nmethod_size = 583 allocation_size(code_buffer, sizeof(nmethod)) 584 + adjust_pcs_size(debug_info->pcs_size()) 585 + round_to(dependencies->size_in_bytes() , oopSize) 586 + round_to(handler_table->size_in_bytes(), oopSize) 587 + round_to(nul_chk_table->size_in_bytes(), oopSize) 588 + round_to(debug_info->data_size() , oopSize); 589 nm = new (nmethod_size) 590 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, 591 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, 592 oop_maps, 593 handler_table, 594 nul_chk_table, 595 compiler, 596 comp_level); 597 if (nm != NULL) { 598 // To make dependency checking during class loading fast, record 599 // the nmethod dependencies in the classes it is dependent on. 600 // This allows the dependency checking code to simply walk the 601 // class hierarchy above the loaded class, checking only nmethods 602 // which are dependent on those classes. The slow way is to 603 // check every nmethod for dependencies which makes it linear in 604 // the number of methods compiled. For applications with a lot 605 // classes the slow way is too slow. 606 for (Dependencies::DepStream deps(nm); deps.next(); ) { 607 Klass* klass = deps.context_type(); 608 if (klass == NULL) continue; // ignore things like evol_method 609 610 // record this nmethod as dependent on this klass 611 InstanceKlass::cast(klass)->add_dependent_nmethod(nm); 612 } 613 } 614 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); 615 if (PrintAssembly && nm != NULL) 616 Disassembler::decode(nm); 617 } 618 619 // verify nmethod 620 debug_only(if (nm) nm->verify();) // might block 621 622 if (nm != NULL) { 623 nm->log_new_nmethod(); 624 } 625 626 // done 627 return nm; 628 } 629 630 631 // For native wrappers 632 nmethod::nmethod( 633 Method* method, 634 int nmethod_size, 635 int compile_id, 636 CodeOffsets* offsets, 637 CodeBuffer* code_buffer, 638 int frame_size, 639 ByteSize basic_lock_owner_sp_offset, 640 ByteSize basic_lock_sp_offset, 641 OopMapSet* oop_maps ) 642 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod), 643 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 644 _native_receiver_sp_offset(basic_lock_owner_sp_offset), 645 _native_basic_lock_sp_offset(basic_lock_sp_offset) 646 { 647 { 648 debug_only(No_Safepoint_Verifier nsv;) 649 assert_locked_or_safepoint(CodeCache_lock); 650 651 init_defaults(); 652 _method = method; 653 _entry_bci = InvocationEntryBci; 654 // We have no exception handler or deopt handler make the 655 // values something that will never match a pc like the nmethod vtable entry 656 _exception_offset = 0; 657 _deoptimize_offset = 0; 658 _deoptimize_mh_offset = 0; 659 _orig_pc_offset = 0; 660 661 _consts_offset = data_offset(); 662 _stub_offset = data_offset(); 663 _oops_offset = data_offset(); 664 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 665 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 666 _scopes_pcs_offset = _scopes_data_offset; 667 _dependencies_offset = _scopes_pcs_offset; 668 _handler_table_offset = _dependencies_offset; 669 _nul_chk_table_offset = _handler_table_offset; 670 _nmethod_end_offset = _nul_chk_table_offset; 671 _compile_id = compile_id; 672 _comp_level = CompLevel_none; 673 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 674 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 675 _osr_entry_point = NULL; 676 _exception_cache = NULL; 677 _pc_desc_cache.reset_to(NULL); 678 679 code_buffer->copy_values_to(this); 680 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 681 CodeCache::add_scavenge_root_nmethod(this); 682 } 683 debug_only(verify_scavenge_root_oops()); 684 CodeCache::commit(this); 685 } 686 687 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 688 ttyLocker ttyl; // keep the following output all in one block 689 // This output goes directly to the tty, not the compiler log. 690 // To enable tools to match it up with the compilation activity, 691 // be sure to tag this tty output with the compile ID. 692 if (xtty != NULL) { 693 xtty->begin_head("print_native_nmethod"); 694 xtty->method(_method); 695 xtty->stamp(); 696 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 697 } 698 // print the header part first 699 print(); 700 // then print the requested information 701 if (PrintNativeNMethods) { 702 print_code(); 703 oop_maps->print(); 704 } 705 if (PrintRelocations) { 706 print_relocations(); 707 } 708 if (xtty != NULL) { 709 xtty->tail("print_native_nmethod"); 710 } 711 } 712 } 713 714 // For dtrace wrappers 715 #ifdef HAVE_DTRACE_H 716 nmethod::nmethod( 717 Method* method, 718 int nmethod_size, 719 CodeOffsets* offsets, 720 CodeBuffer* code_buffer, 721 int frame_size) 722 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod), 723 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL), 724 _native_receiver_sp_offset(in_ByteSize(-1)), 725 _native_basic_lock_sp_offset(in_ByteSize(-1)) 726 { 727 { 728 debug_only(No_Safepoint_Verifier nsv;) 729 assert_locked_or_safepoint(CodeCache_lock); 730 731 init_defaults(); 732 _method = method; 733 _entry_bci = InvocationEntryBci; 734 // We have no exception handler or deopt handler make the 735 // values something that will never match a pc like the nmethod vtable entry 736 _exception_offset = 0; 737 _deoptimize_offset = 0; 738 _deoptimize_mh_offset = 0; 739 _unwind_handler_offset = -1; 740 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap); 741 _orig_pc_offset = 0; 742 _consts_offset = data_offset(); 743 _stub_offset = data_offset(); 744 _oops_offset = data_offset(); 745 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 746 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 747 _scopes_pcs_offset = _scopes_data_offset; 748 _dependencies_offset = _scopes_pcs_offset; 749 _handler_table_offset = _dependencies_offset; 750 _nul_chk_table_offset = _handler_table_offset; 751 _nmethod_end_offset = _nul_chk_table_offset; 752 _compile_id = 0; // default 753 _comp_level = CompLevel_none; 754 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 755 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 756 _osr_entry_point = NULL; 757 _exception_cache = NULL; 758 _pc_desc_cache.reset_to(NULL); 759 760 code_buffer->copy_values_to(this); 761 debug_only(verify_scavenge_root_oops()); 762 CodeCache::commit(this); 763 } 764 765 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 766 ttyLocker ttyl; // keep the following output all in one block 767 // This output goes directly to the tty, not the compiler log. 768 // To enable tools to match it up with the compilation activity, 769 // be sure to tag this tty output with the compile ID. 770 if (xtty != NULL) { 771 xtty->begin_head("print_dtrace_nmethod"); 772 xtty->method(_method); 773 xtty->stamp(); 774 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 775 } 776 // print the header part first 777 print(); 778 // then print the requested information 779 if (PrintNMethods) { 780 print_code(); 781 } 782 if (PrintRelocations) { 783 print_relocations(); 784 } 785 if (xtty != NULL) { 786 xtty->tail("print_dtrace_nmethod"); 787 } 788 } 789 } 790 #endif // def HAVE_DTRACE_H 791 792 void* nmethod::operator new(size_t size, int nmethod_size) { 793 // Always leave some room in the CodeCache for I2C/C2I adapters 794 if (CodeCache::largest_free_block() < CodeCacheMinimumFreeSpace) return NULL; 795 return CodeCache::allocate(nmethod_size); 796 } 797 798 799 nmethod::nmethod( 800 Method* method, 801 int nmethod_size, 802 int compile_id, 803 int entry_bci, 804 CodeOffsets* offsets, 805 int orig_pc_offset, 806 DebugInformationRecorder* debug_info, 807 Dependencies* dependencies, 808 CodeBuffer *code_buffer, 809 int frame_size, 810 OopMapSet* oop_maps, 811 ExceptionHandlerTable* handler_table, 812 ImplicitExceptionTable* nul_chk_table, 813 AbstractCompiler* compiler, 814 int comp_level 815 ) 816 : CodeBlob("nmethod", code_buffer, sizeof(nmethod), 817 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 818 _native_receiver_sp_offset(in_ByteSize(-1)), 819 _native_basic_lock_sp_offset(in_ByteSize(-1)) 820 { 821 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 822 { 823 debug_only(No_Safepoint_Verifier nsv;) 824 assert_locked_or_safepoint(CodeCache_lock); 825 826 init_defaults(); 827 _method = method; 828 _entry_bci = entry_bci; 829 _compile_id = compile_id; 830 _comp_level = comp_level; 831 _compiler = compiler; 832 _orig_pc_offset = orig_pc_offset; 833 834 // Section offsets 835 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts()); 836 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs()); 837 838 // Exception handler and deopt handler are in the stub section 839 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set"); 840 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set"); 841 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions); 842 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt); 843 if (offsets->value(CodeOffsets::DeoptMH) != -1) { 844 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH); 845 } else { 846 _deoptimize_mh_offset = -1; 847 } 848 if (offsets->value(CodeOffsets::UnwindHandler) != -1) { 849 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler); 850 } else { 851 _unwind_handler_offset = -1; 852 } 853 854 _oops_offset = data_offset(); 855 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 856 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 857 858 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize); 859 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size()); 860 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize); 861 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize); 862 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize); 863 864 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 865 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 866 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry); 867 _exception_cache = NULL; 868 _pc_desc_cache.reset_to(scopes_pcs_begin()); 869 870 // Copy contents of ScopeDescRecorder to nmethod 871 code_buffer->copy_values_to(this); 872 debug_info->copy_to(this); 873 dependencies->copy_to(this); 874 if (ScavengeRootsInCode && detect_scavenge_root_oops()) { 875 CodeCache::add_scavenge_root_nmethod(this); 876 } 877 debug_only(verify_scavenge_root_oops()); 878 879 CodeCache::commit(this); 880 881 // Copy contents of ExceptionHandlerTable to nmethod 882 handler_table->copy_to(this); 883 nul_chk_table->copy_to(this); 884 885 // we use the information of entry points to find out if a method is 886 // static or non static 887 assert(compiler->is_c2() || 888 _method->is_static() == (entry_point() == _verified_entry_point), 889 " entry points must be same for static methods and vice versa"); 890 } 891 892 bool printnmethods = PrintNMethods 893 || CompilerOracle::should_print(_method) 894 || CompilerOracle::has_option_string(_method, "PrintNMethods"); 895 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) { 896 print_nmethod(printnmethods); 897 } 898 } 899 900 901 // Print a short set of xml attributes to identify this nmethod. The 902 // output should be embedded in some other element. 903 void nmethod::log_identity(xmlStream* log) const { 904 log->print(" compile_id='%d'", compile_id()); 905 const char* nm_kind = compile_kind(); 906 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind); 907 if (compiler() != NULL) { 908 log->print(" compiler='%s'", compiler()->name()); 909 } 910 if (TieredCompilation) { 911 log->print(" level='%d'", comp_level()); 912 } 913 } 914 915 916 #define LOG_OFFSET(log, name) \ 917 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \ 918 log->print(" " XSTR(name) "_offset='%d'" , \ 919 (intptr_t)name##_begin() - (intptr_t)this) 920 921 922 void nmethod::log_new_nmethod() const { 923 if (LogCompilation && xtty != NULL) { 924 ttyLocker ttyl; 925 HandleMark hm; 926 xtty->begin_elem("nmethod"); 927 log_identity(xtty); 928 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size()); 929 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this); 930 931 LOG_OFFSET(xtty, relocation); 932 LOG_OFFSET(xtty, consts); 933 LOG_OFFSET(xtty, insts); 934 LOG_OFFSET(xtty, stub); 935 LOG_OFFSET(xtty, scopes_data); 936 LOG_OFFSET(xtty, scopes_pcs); 937 LOG_OFFSET(xtty, dependencies); 938 LOG_OFFSET(xtty, handler_table); 939 LOG_OFFSET(xtty, nul_chk_table); 940 LOG_OFFSET(xtty, oops); 941 942 xtty->method(method()); 943 xtty->stamp(); 944 xtty->end_elem(); 945 } 946 } 947 948 #undef LOG_OFFSET 949 950 951 // Print out more verbose output usually for a newly created nmethod. 952 void nmethod::print_on(outputStream* st, const char* msg) const { 953 if (st != NULL) { 954 ttyLocker ttyl; 955 if (WizardMode) { 956 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true); 957 st->print_cr(" (" INTPTR_FORMAT ")", this); 958 } else { 959 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false); 960 } 961 } 962 } 963 964 965 void nmethod::print_nmethod(bool printmethod) { 966 ttyLocker ttyl; // keep the following output all in one block 967 if (xtty != NULL) { 968 xtty->begin_head("print_nmethod"); 969 xtty->stamp(); 970 xtty->end_head(); 971 } 972 // print the header part first 973 print(); 974 // then print the requested information 975 if (printmethod) { 976 print_code(); 977 print_pcs(); 978 if (oop_maps()) { 979 oop_maps()->print(); 980 } 981 } 982 if (PrintDebugInfo) { 983 print_scopes(); 984 } 985 if (PrintRelocations) { 986 print_relocations(); 987 } 988 if (PrintDependencies) { 989 print_dependencies(); 990 } 991 if (PrintExceptionHandlers) { 992 print_handler_table(); 993 print_nul_chk_table(); 994 } 995 if (xtty != NULL) { 996 xtty->tail("print_nmethod"); 997 } 998 } 999 1000 1001 // Promote one word from an assembly-time handle to a live embedded oop. 1002 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) { 1003 if (handle == NULL || 1004 // As a special case, IC oops are initialized to 1 or -1. 1005 handle == (jobject) Universe::non_oop_word()) { 1006 (*dest) = (oop) handle; 1007 } else { 1008 (*dest) = JNIHandles::resolve_non_null(handle); 1009 } 1010 } 1011 1012 1013 // Have to have the same name because it's called by a template 1014 void nmethod::copy_values(GrowableArray<jobject>* array) { 1015 int length = array->length(); 1016 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough"); 1017 oop* dest = oops_begin(); 1018 for (int index = 0 ; index < length; index++) { 1019 initialize_immediate_oop(&dest[index], array->at(index)); 1020 } 1021 1022 // Now we can fix up all the oops in the code. We need to do this 1023 // in the code because the assembler uses jobjects as placeholders. 1024 // The code and relocations have already been initialized by the 1025 // CodeBlob constructor, so it is valid even at this early point to 1026 // iterate over relocations and patch the code. 1027 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true); 1028 } 1029 1030 void nmethod::copy_values(GrowableArray<Metadata*>* array) { 1031 int length = array->length(); 1032 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough"); 1033 Metadata** dest = metadata_begin(); 1034 for (int index = 0 ; index < length; index++) { 1035 dest[index] = array->at(index); 1036 } 1037 } 1038 1039 bool nmethod::is_at_poll_return(address pc) { 1040 RelocIterator iter(this, pc, pc+1); 1041 while (iter.next()) { 1042 if (iter.type() == relocInfo::poll_return_type) 1043 return true; 1044 } 1045 return false; 1046 } 1047 1048 1049 bool nmethod::is_at_poll_or_poll_return(address pc) { 1050 RelocIterator iter(this, pc, pc+1); 1051 while (iter.next()) { 1052 relocInfo::relocType t = iter.type(); 1053 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type) 1054 return true; 1055 } 1056 return false; 1057 } 1058 1059 1060 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) { 1061 // re-patch all oop-bearing instructions, just in case some oops moved 1062 RelocIterator iter(this, begin, end); 1063 while (iter.next()) { 1064 if (iter.type() == relocInfo::oop_type) { 1065 oop_Relocation* reloc = iter.oop_reloc(); 1066 if (initialize_immediates && reloc->oop_is_immediate()) { 1067 oop* dest = reloc->oop_addr(); 1068 initialize_immediate_oop(dest, (jobject) *dest); 1069 } 1070 // Refresh the oop-related bits of this instruction. 1071 reloc->fix_oop_relocation(); 1072 } else if (iter.type() == relocInfo::metadata_type) { 1073 metadata_Relocation* reloc = iter.metadata_reloc(); 1074 reloc->fix_metadata_relocation(); 1075 } 1076 1077 // There must not be any interfering patches or breakpoints. 1078 assert(!(iter.type() == relocInfo::breakpoint_type 1079 && iter.breakpoint_reloc()->active()), 1080 "no active breakpoint"); 1081 } 1082 } 1083 1084 1085 void nmethod::verify_oop_relocations() { 1086 // Ensure sure that the code matches the current oop values 1087 RelocIterator iter(this, NULL, NULL); 1088 while (iter.next()) { 1089 if (iter.type() == relocInfo::oop_type) { 1090 oop_Relocation* reloc = iter.oop_reloc(); 1091 if (!reloc->oop_is_immediate()) { 1092 reloc->verify_oop_relocation(); 1093 } 1094 } 1095 } 1096 } 1097 1098 1099 ScopeDesc* nmethod::scope_desc_at(address pc) { 1100 PcDesc* pd = pc_desc_at(pc); 1101 guarantee(pd != NULL, "scope must be present"); 1102 return new ScopeDesc(this, pd->scope_decode_offset(), 1103 pd->obj_decode_offset(), pd->should_reexecute(), 1104 pd->return_oop()); 1105 } 1106 1107 1108 void nmethod::clear_inline_caches() { 1109 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint"); 1110 if (is_zombie()) { 1111 return; 1112 } 1113 1114 RelocIterator iter(this); 1115 while (iter.next()) { 1116 iter.reloc()->clear_inline_cache(); 1117 } 1118 } 1119 1120 1121 void nmethod::cleanup_inline_caches() { 1122 1123 assert_locked_or_safepoint(CompiledIC_lock); 1124 1125 // If the method is not entrant or zombie then a JMP is plastered over the 1126 // first few bytes. If an oop in the old code was there, that oop 1127 // should not get GC'd. Skip the first few bytes of oops on 1128 // not-entrant methods. 1129 address low_boundary = verified_entry_point(); 1130 if (!is_in_use()) { 1131 low_boundary += NativeJump::instruction_size; 1132 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1133 // This means that the low_boundary is going to be a little too high. 1134 // This shouldn't matter, since oops of non-entrant methods are never used. 1135 // In fact, why are we bothering to look at oops in a non-entrant method?? 1136 } 1137 1138 // Find all calls in an nmethod, and clear the ones that points to zombie methods 1139 ResourceMark rm; 1140 RelocIterator iter(this, low_boundary); 1141 while(iter.next()) { 1142 switch(iter.type()) { 1143 case relocInfo::virtual_call_type: 1144 case relocInfo::opt_virtual_call_type: { 1145 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1146 // Ok, to lookup references to zombies here 1147 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1148 if( cb != NULL && cb->is_nmethod() ) { 1149 nmethod* nm = (nmethod*)cb; 1150 // Clean inline caches pointing to both zombie and not_entrant methods 1151 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(); 1152 } 1153 break; 1154 } 1155 case relocInfo::static_call_type: { 1156 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1157 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1158 if( cb != NULL && cb->is_nmethod() ) { 1159 nmethod* nm = (nmethod*)cb; 1160 // Clean inline caches pointing to both zombie and not_entrant methods 1161 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean(); 1162 } 1163 break; 1164 } 1165 } 1166 } 1167 } 1168 1169 // This is a private interface with the sweeper. 1170 void nmethod::mark_as_seen_on_stack() { 1171 assert(is_not_entrant(), "must be a non-entrant method"); 1172 // Set the traversal mark to ensure that the sweeper does 2 1173 // cleaning passes before moving to zombie. 1174 set_stack_traversal_mark(NMethodSweeper::traversal_count()); 1175 } 1176 1177 // Tell if a non-entrant method can be converted to a zombie (i.e., 1178 // there are no activations on the stack, not in use by the VM, 1179 // and not in use by the ServiceThread) 1180 bool nmethod::can_not_entrant_be_converted() { 1181 assert(is_not_entrant(), "must be a non-entrant method"); 1182 1183 // Since the nmethod sweeper only does partial sweep the sweeper's traversal 1184 // count can be greater than the stack traversal count before it hits the 1185 // nmethod for the second time. 1186 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() && 1187 !is_locked_by_vm(); 1188 } 1189 1190 void nmethod::inc_decompile_count() { 1191 if (!is_compiled_by_c2()) return; 1192 // Could be gated by ProfileTraps, but do not bother... 1193 Method* m = method(); 1194 if (m == NULL) return; 1195 MethodData* mdo = m->method_data(); 1196 if (mdo == NULL) return; 1197 // There is a benign race here. See comments in methodData.hpp. 1198 mdo->inc_decompile_count(); 1199 } 1200 1201 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) { 1202 1203 post_compiled_method_unload(); 1204 1205 // Since this nmethod is being unloaded, make sure that dependencies 1206 // recorded in instanceKlasses get flushed and pass non-NULL closure to 1207 // indicate that this work is being done during a GC. 1208 assert(Universe::heap()->is_gc_active(), "should only be called during gc"); 1209 assert(is_alive != NULL, "Should be non-NULL"); 1210 // A non-NULL is_alive closure indicates that this is being called during GC. 1211 flush_dependencies(is_alive); 1212 1213 // Break cycle between nmethod & method 1214 if (TraceClassUnloading && WizardMode) { 1215 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT 1216 " unloadable], Method*(" INTPTR_FORMAT 1217 "), cause(" INTPTR_FORMAT ")", 1218 this, (address)_method, (address)cause); 1219 if (!Universe::heap()->is_gc_active()) 1220 cause->klass()->print(); 1221 } 1222 // Unlink the osr method, so we do not look this up again 1223 if (is_osr_method()) { 1224 invalidate_osr_method(); 1225 } 1226 // If _method is already NULL the Method* is about to be unloaded, 1227 // so we don't have to break the cycle. Note that it is possible to 1228 // have the Method* live here, in case we unload the nmethod because 1229 // it is pointing to some oop (other than the Method*) being unloaded. 1230 if (_method != NULL) { 1231 // OSR methods point to the Method*, but the Method* does not 1232 // point back! 1233 if (_method->code() == this) { 1234 _method->clear_code(); // Break a cycle 1235 } 1236 _method = NULL; // Clear the method of this dead nmethod 1237 } 1238 // Make the class unloaded - i.e., change state and notify sweeper 1239 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1240 if (is_in_use()) { 1241 // Transitioning directly from live to unloaded -- so 1242 // we need to force a cache clean-up; remember this 1243 // for later on. 1244 CodeCache::set_needs_cache_clean(true); 1245 } 1246 _state = unloaded; 1247 1248 // Log the unloading. 1249 log_state_change(); 1250 1251 // The Method* is gone at this point 1252 assert(_method == NULL, "Tautology"); 1253 1254 set_osr_link(NULL); 1255 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods 1256 NMethodSweeper::notify(this); 1257 } 1258 1259 void nmethod::invalidate_osr_method() { 1260 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); 1261 // Remove from list of active nmethods 1262 if (method() != NULL) 1263 InstanceKlass::cast(method()->method_holder())->remove_osr_nmethod(this); 1264 // Set entry as invalid 1265 _entry_bci = InvalidOSREntryBci; 1266 } 1267 1268 void nmethod::log_state_change() const { 1269 if (LogCompilation) { 1270 if (xtty != NULL) { 1271 ttyLocker ttyl; // keep the following output all in one block 1272 if (_state == unloaded) { 1273 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'", 1274 os::current_thread_id()); 1275 } else { 1276 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s", 1277 os::current_thread_id(), 1278 (_state == zombie ? " zombie='1'" : "")); 1279 } 1280 log_identity(xtty); 1281 xtty->stamp(); 1282 xtty->end_elem(); 1283 } 1284 } 1285 if (PrintCompilation && _state != unloaded) { 1286 print_on(tty, _state == zombie ? "made zombie" : "made not entrant"); 1287 } 1288 } 1289 1290 // Common functionality for both make_not_entrant and make_zombie 1291 bool nmethod::make_not_entrant_or_zombie(unsigned int state) { 1292 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant"); 1293 assert(!is_zombie(), "should not already be a zombie"); 1294 1295 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below. 1296 nmethodLocker nml(this); 1297 methodHandle the_method(method()); 1298 No_Safepoint_Verifier nsv; 1299 1300 { 1301 // invalidate osr nmethod before acquiring the patching lock since 1302 // they both acquire leaf locks and we don't want a deadlock. 1303 // This logic is equivalent to the logic below for patching the 1304 // verified entry point of regular methods. 1305 if (is_osr_method()) { 1306 // this effectively makes the osr nmethod not entrant 1307 invalidate_osr_method(); 1308 } 1309 1310 // Enter critical section. Does not block for safepoint. 1311 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1312 1313 if (_state == state) { 1314 // another thread already performed this transition so nothing 1315 // to do, but return false to indicate this. 1316 return false; 1317 } 1318 1319 // The caller can be calling the method statically or through an inline 1320 // cache call. 1321 if (!is_osr_method() && !is_not_entrant()) { 1322 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(), 1323 SharedRuntime::get_handle_wrong_method_stub()); 1324 } 1325 1326 if (is_in_use()) { 1327 // It's a true state change, so mark the method as decompiled. 1328 // Do it only for transition from alive. 1329 inc_decompile_count(); 1330 } 1331 1332 // Change state 1333 _state = state; 1334 1335 // Log the transition once 1336 log_state_change(); 1337 1338 // Remove nmethod from method. 1339 // We need to check if both the _code and _from_compiled_code_entry_point 1340 // refer to this nmethod because there is a race in setting these two fields 1341 // in Method* as seen in bugid 4947125. 1342 // If the vep() points to the zombie nmethod, the memory for the nmethod 1343 // could be flushed and the compiler and vtable stubs could still call 1344 // through it. 1345 if (method() != NULL && (method()->code() == this || 1346 method()->from_compiled_entry() == verified_entry_point())) { 1347 HandleMark hm; 1348 method()->clear_code(); 1349 } 1350 1351 if (state == not_entrant) { 1352 mark_as_seen_on_stack(); 1353 } 1354 1355 } // leave critical region under Patching_lock 1356 1357 // When the nmethod becomes zombie it is no longer alive so the 1358 // dependencies must be flushed. nmethods in the not_entrant 1359 // state will be flushed later when the transition to zombie 1360 // happens or they get unloaded. 1361 if (state == zombie) { 1362 { 1363 // Flushing dependecies must be done before any possible 1364 // safepoint can sneak in, otherwise the oops used by the 1365 // dependency logic could have become stale. 1366 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1367 flush_dependencies(NULL); 1368 } 1369 1370 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload 1371 // event and it hasn't already been reported for this nmethod then 1372 // report it now. The event may have been reported earilier if the GC 1373 // marked it for unloading). JvmtiDeferredEventQueue support means 1374 // we no longer go to a safepoint here. 1375 post_compiled_method_unload(); 1376 1377 #ifdef ASSERT 1378 // It's no longer safe to access the oops section since zombie 1379 // nmethods aren't scanned for GC. 1380 _oops_are_stale = true; 1381 #endif 1382 } else { 1383 assert(state == not_entrant, "other cases may need to be handled differently"); 1384 } 1385 1386 if (TraceCreateZombies) { 1387 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie"); 1388 } 1389 1390 // Make sweeper aware that there is a zombie method that needs to be removed 1391 NMethodSweeper::notify(this); 1392 1393 return true; 1394 } 1395 1396 void nmethod::flush() { 1397 // Note that there are no valid oops in the nmethod anymore. 1398 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method"); 1399 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation"); 1400 1401 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed"); 1402 assert_locked_or_safepoint(CodeCache_lock); 1403 1404 // completely deallocate this method 1405 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this); 1406 if (PrintMethodFlushing) { 1407 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb", 1408 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024); 1409 } 1410 1411 // We need to deallocate any ExceptionCache data. 1412 // Note that we do not need to grab the nmethod lock for this, it 1413 // better be thread safe if we're disposing of it! 1414 ExceptionCache* ec = exception_cache(); 1415 set_exception_cache(NULL); 1416 while(ec != NULL) { 1417 ExceptionCache* next = ec->next(); 1418 delete ec; 1419 ec = next; 1420 } 1421 1422 if (on_scavenge_root_list()) { 1423 CodeCache::drop_scavenge_root_nmethod(this); 1424 } 1425 1426 if (is_speculatively_disconnected()) { 1427 CodeCache::remove_saved_code(this); 1428 } 1429 1430 #ifdef SHARK 1431 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin()); 1432 #endif // SHARK 1433 1434 ((CodeBlob*)(this))->flush(); 1435 1436 CodeCache::free(this); 1437 } 1438 1439 1440 // 1441 // Notify all classes this nmethod is dependent on that it is no 1442 // longer dependent. This should only be called in two situations. 1443 // First, when a nmethod transitions to a zombie all dependents need 1444 // to be clear. Since zombification happens at a safepoint there's no 1445 // synchronization issues. The second place is a little more tricky. 1446 // During phase 1 of mark sweep class unloading may happen and as a 1447 // result some nmethods may get unloaded. In this case the flushing 1448 // of dependencies must happen during phase 1 since after GC any 1449 // dependencies in the unloaded nmethod won't be updated, so 1450 // traversing the dependency information in unsafe. In that case this 1451 // function is called with a non-NULL argument and this function only 1452 // notifies instanceKlasses that are reachable 1453 1454 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) { 1455 assert_locked_or_safepoint(CodeCache_lock); 1456 assert(Universe::heap()->is_gc_active() == (is_alive != NULL), 1457 "is_alive is non-NULL if and only if we are called during GC"); 1458 if (!has_flushed_dependencies()) { 1459 set_has_flushed_dependencies(); 1460 for (Dependencies::DepStream deps(this); deps.next(); ) { 1461 Klass* klass = deps.context_type(); 1462 if (klass == NULL) continue; // ignore things like evol_method 1463 1464 // During GC the is_alive closure is non-NULL, and is used to 1465 // determine liveness of dependees that need to be updated. 1466 if (is_alive == NULL || klass->is_loader_alive(is_alive)) { 1467 InstanceKlass::cast(klass)->remove_dependent_nmethod(this); 1468 } 1469 } 1470 } 1471 } 1472 1473 1474 // If this oop is not live, the nmethod can be unloaded. 1475 bool nmethod::can_unload(BoolObjectClosure* is_alive, 1476 OopClosure* keep_alive, 1477 oop* root, bool unloading_occurred) { 1478 assert(root != NULL, "just checking"); 1479 oop obj = *root; 1480 if (obj == NULL || is_alive->do_object_b(obj)) { 1481 return false; 1482 } 1483 1484 // If ScavengeRootsInCode is true, an nmethod might be unloaded 1485 // simply because one of its constant oops has gone dead. 1486 // No actual classes need to be unloaded in order for this to occur. 1487 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading"); 1488 make_unloaded(is_alive, obj); 1489 return true; 1490 } 1491 1492 // ------------------------------------------------------------------ 1493 // post_compiled_method_load_event 1494 // new method for install_code() path 1495 // Transfer information from compilation to jvmti 1496 void nmethod::post_compiled_method_load_event() { 1497 1498 Method* moop = method(); 1499 #ifndef USDT2 1500 HS_DTRACE_PROBE8(hotspot, compiled__method__load, 1501 moop->klass_name()->bytes(), 1502 moop->klass_name()->utf8_length(), 1503 moop->name()->bytes(), 1504 moop->name()->utf8_length(), 1505 moop->signature()->bytes(), 1506 moop->signature()->utf8_length(), 1507 insts_begin(), insts_size()); 1508 #else /* USDT2 */ 1509 HOTSPOT_COMPILED_METHOD_LOAD( 1510 (char *) moop->klass_name()->bytes(), 1511 moop->klass_name()->utf8_length(), 1512 (char *) moop->name()->bytes(), 1513 moop->name()->utf8_length(), 1514 (char *) moop->signature()->bytes(), 1515 moop->signature()->utf8_length(), 1516 insts_begin(), insts_size()); 1517 #endif /* USDT2 */ 1518 1519 if (JvmtiExport::should_post_compiled_method_load() || 1520 JvmtiExport::should_post_compiled_method_unload()) { 1521 get_and_cache_jmethod_id(); 1522 } 1523 1524 if (JvmtiExport::should_post_compiled_method_load()) { 1525 // Let the Service thread (which is a real Java thread) post the event 1526 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1527 JvmtiDeferredEventQueue::enqueue( 1528 JvmtiDeferredEvent::compiled_method_load_event(this)); 1529 } 1530 } 1531 1532 jmethodID nmethod::get_and_cache_jmethod_id() { 1533 if (_jmethod_id == NULL) { 1534 // Cache the jmethod_id since it can no longer be looked up once the 1535 // method itself has been marked for unloading. 1536 _jmethod_id = method()->jmethod_id(); 1537 } 1538 return _jmethod_id; 1539 } 1540 1541 void nmethod::post_compiled_method_unload() { 1542 if (unload_reported()) { 1543 // During unloading we transition to unloaded and then to zombie 1544 // and the unloading is reported during the first transition. 1545 return; 1546 } 1547 1548 assert(_method != NULL && !is_unloaded(), "just checking"); 1549 DTRACE_METHOD_UNLOAD_PROBE(method()); 1550 1551 // If a JVMTI agent has enabled the CompiledMethodUnload event then 1552 // post the event. Sometime later this nmethod will be made a zombie 1553 // by the sweeper but the Method* will not be valid at that point. 1554 // If the _jmethod_id is null then no load event was ever requested 1555 // so don't bother posting the unload. The main reason for this is 1556 // that the jmethodID is a weak reference to the Method* so if 1557 // it's being unloaded there's no way to look it up since the weak 1558 // ref will have been cleared. 1559 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) { 1560 assert(!unload_reported(), "already unloaded"); 1561 JvmtiDeferredEvent event = 1562 JvmtiDeferredEvent::compiled_method_unload_event(this, 1563 _jmethod_id, insts_begin()); 1564 if (SafepointSynchronize::is_at_safepoint()) { 1565 // Don't want to take the queueing lock. Add it as pending and 1566 // it will get enqueued later. 1567 JvmtiDeferredEventQueue::add_pending_event(event); 1568 } else { 1569 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1570 JvmtiDeferredEventQueue::enqueue(event); 1571 } 1572 } 1573 1574 // The JVMTI CompiledMethodUnload event can be enabled or disabled at 1575 // any time. As the nmethod is being unloaded now we mark it has 1576 // having the unload event reported - this will ensure that we don't 1577 // attempt to report the event in the unlikely scenario where the 1578 // event is enabled at the time the nmethod is made a zombie. 1579 set_unload_reported(); 1580 } 1581 1582 // This is called at the end of the strong tracing/marking phase of a 1583 // GC to unload an nmethod if it contains otherwise unreachable 1584 // oops. 1585 1586 void nmethod::do_unloading(BoolObjectClosure* is_alive, 1587 OopClosure* keep_alive, bool unloading_occurred) { 1588 // Make sure the oop's ready to receive visitors 1589 assert(!is_zombie() && !is_unloaded(), 1590 "should not call follow on zombie or unloaded nmethod"); 1591 1592 // If the method is not entrant then a JMP is plastered over the 1593 // first few bytes. If an oop in the old code was there, that oop 1594 // should not get GC'd. Skip the first few bytes of oops on 1595 // not-entrant methods. 1596 address low_boundary = verified_entry_point(); 1597 if (is_not_entrant()) { 1598 low_boundary += NativeJump::instruction_size; 1599 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1600 // (See comment above.) 1601 } 1602 1603 // The RedefineClasses() API can cause the class unloading invariant 1604 // to no longer be true. See jvmtiExport.hpp for details. 1605 // Also, leave a debugging breadcrumb in local flag. 1606 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class(); 1607 if (a_class_was_redefined) { 1608 // This set of the unloading_occurred flag is done before the 1609 // call to post_compiled_method_unload() so that the unloading 1610 // of this nmethod is reported. 1611 unloading_occurred = true; 1612 } 1613 1614 // Exception cache 1615 ExceptionCache* ec = exception_cache(); 1616 while (ec != NULL) { 1617 Klass* ex_klass = ec->exception_type(); 1618 ExceptionCache* next_ec = ec->next(); 1619 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) { 1620 remove_from_exception_cache(ec); 1621 } 1622 ec = next_ec; 1623 } 1624 1625 // If class unloading occurred we first iterate over all inline caches and 1626 // clear ICs where the cached oop is referring to an unloaded klass or method. 1627 // The remaining live cached oops will be traversed in the relocInfo::oop_type 1628 // iteration below. 1629 if (unloading_occurred) { 1630 RelocIterator iter(this, low_boundary); 1631 while(iter.next()) { 1632 if (iter.type() == relocInfo::virtual_call_type) { 1633 CompiledIC *ic = CompiledIC_at(iter.reloc()); 1634 if (ic->is_icholder_call()) { 1635 // The only exception is compiledICHolder oops which may 1636 // yet be marked below. (We check this further below). 1637 CompiledICHolder* cichk_oop = ic->cached_icholder(); 1638 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) && 1639 cichk_oop->holder_klass()->is_loader_alive(is_alive)) { 1640 continue; 1641 } 1642 } else { 1643 Metadata* ic_oop = ic->cached_metadata(); 1644 if (ic_oop != NULL) { 1645 if (ic_oop->is_klass()) { 1646 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) { 1647 continue; 1648 } 1649 } else if (ic_oop->is_method()) { 1650 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) { 1651 continue; 1652 } 1653 } else { 1654 ShouldNotReachHere(); 1655 } 1656 } 1657 } 1658 ic->set_to_clean(); 1659 } 1660 } 1661 } 1662 1663 // Compiled code 1664 { 1665 RelocIterator iter(this, low_boundary); 1666 while (iter.next()) { 1667 if (iter.type() == relocInfo::oop_type) { 1668 oop_Relocation* r = iter.oop_reloc(); 1669 // In this loop, we must only traverse those oops directly embedded in 1670 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1671 assert(1 == (r->oop_is_immediate()) + 1672 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1673 "oop must be found in exactly one place"); 1674 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1675 if (can_unload(is_alive, keep_alive, r->oop_addr(), unloading_occurred)) { 1676 return; 1677 } 1678 } 1679 } 1680 } 1681 } 1682 1683 1684 // Scopes 1685 for (oop* p = oops_begin(); p < oops_end(); p++) { 1686 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1687 if (can_unload(is_alive, keep_alive, p, unloading_occurred)) { 1688 return; 1689 } 1690 } 1691 1692 // Ensure that all metadata is still alive 1693 verify_metadata_loaders(low_boundary, is_alive); 1694 } 1695 1696 #ifdef ASSERT 1697 1698 class CheckClass : AllStatic { 1699 static BoolObjectClosure* _is_alive; 1700 1701 // Check class_loader is alive for this bit of metadata. 1702 static void check_class(Metadata* md) { 1703 Klass* klass = NULL; 1704 if (md->is_klass()) { 1705 klass = ((Klass*)md); 1706 } else if (md->is_method()) { 1707 klass = ((Method*)md)->method_holder(); 1708 } else if (md->is_methodData()) { 1709 klass = ((MethodData*)md)->method()->method_holder(); 1710 } else { 1711 md->print(); 1712 ShouldNotReachHere(); 1713 } 1714 assert(klass->is_loader_alive(_is_alive), "must be alive"); 1715 } 1716 public: 1717 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) { 1718 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint"); 1719 _is_alive = is_alive; 1720 nm->metadata_do(check_class); 1721 } 1722 }; 1723 1724 // This is called during a safepoint so can use static data 1725 BoolObjectClosure* CheckClass::_is_alive = NULL; 1726 #endif // ASSERT 1727 1728 1729 // Processing of oop references should have been sufficient to keep 1730 // all strong references alive. Any weak references should have been 1731 // cleared as well. Visit all the metadata and ensure that it's 1732 // really alive. 1733 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) { 1734 #ifdef ASSERT 1735 RelocIterator iter(this, low_boundary); 1736 while (iter.next()) { 1737 // static_stub_Relocations may have dangling references to 1738 // Method*s so trim them out here. Otherwise it looks like 1739 // compiled code is maintaining a link to dead metadata. 1740 address static_call_addr = NULL; 1741 if (iter.type() == relocInfo::opt_virtual_call_type) { 1742 CompiledIC* cic = CompiledIC_at(iter.reloc()); 1743 if (!cic->is_call_to_interpreted()) { 1744 static_call_addr = iter.addr(); 1745 } 1746 } else if (iter.type() == relocInfo::static_call_type) { 1747 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc()); 1748 if (!csc->is_call_to_interpreted()) { 1749 static_call_addr = iter.addr(); 1750 } 1751 } 1752 if (static_call_addr != NULL) { 1753 RelocIterator sciter(this, low_boundary); 1754 while (sciter.next()) { 1755 if (sciter.type() == relocInfo::static_stub_type && 1756 sciter.static_stub_reloc()->static_call() == static_call_addr) { 1757 sciter.static_stub_reloc()->clear_inline_cache(); 1758 } 1759 } 1760 } 1761 } 1762 // Check that the metadata embedded in the nmethod is alive 1763 CheckClass::do_check_class(is_alive, this); 1764 #endif 1765 } 1766 1767 1768 // Iterate over metadata calling this function. Used by RedefineClasses 1769 void nmethod::metadata_do(void f(Metadata*)) { 1770 address low_boundary = verified_entry_point(); 1771 if (is_not_entrant()) { 1772 low_boundary += NativeJump::instruction_size; 1773 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1774 // (See comment above.) 1775 } 1776 { 1777 // Visit all immediate references that are embedded in the instruction stream. 1778 RelocIterator iter(this, low_boundary); 1779 while (iter.next()) { 1780 if (iter.type() == relocInfo::metadata_type ) { 1781 metadata_Relocation* r = iter.metadata_reloc(); 1782 // In this lmetadata, we must only follow those metadatas directly embedded in 1783 // the code. Other metadatas (oop_index>0) are seen as part of 1784 // the metadata section below. 1785 assert(1 == (r->metadata_is_immediate()) + 1786 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), 1787 "metadata must be found in exactly one place"); 1788 if (r->metadata_is_immediate() && r->metadata_value() != NULL) { 1789 Metadata* md = r->metadata_value(); 1790 f(md); 1791 } 1792 } 1793 } 1794 } 1795 1796 // Visit the metadata section 1797 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { 1798 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops 1799 Metadata* md = *p; 1800 f(md); 1801 } 1802 // Call function Method*, not embedded in these other places. 1803 if (_method != NULL) f(_method); 1804 } 1805 1806 1807 // This method is called twice during GC -- once while 1808 // tracing the "active" nmethods on thread stacks during 1809 // the (strong) marking phase, and then again when walking 1810 // the code cache contents during the weak roots processing 1811 // phase. The two uses are distinguished by means of the 1812 // 'do_strong_roots_only' flag, which is true in the first 1813 // case. We want to walk the weak roots in the nmethod 1814 // only in the second case. The weak roots in the nmethod 1815 // are the oops in the ExceptionCache and the InlineCache 1816 // oops. 1817 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) { 1818 // make sure the oops ready to receive visitors 1819 assert(!is_zombie() && !is_unloaded(), 1820 "should not call follow on zombie or unloaded nmethod"); 1821 1822 // If the method is not entrant or zombie then a JMP is plastered over the 1823 // first few bytes. If an oop in the old code was there, that oop 1824 // should not get GC'd. Skip the first few bytes of oops on 1825 // not-entrant methods. 1826 address low_boundary = verified_entry_point(); 1827 if (is_not_entrant()) { 1828 low_boundary += NativeJump::instruction_size; 1829 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1830 // (See comment above.) 1831 } 1832 1833 RelocIterator iter(this, low_boundary); 1834 1835 while (iter.next()) { 1836 if (iter.type() == relocInfo::oop_type ) { 1837 oop_Relocation* r = iter.oop_reloc(); 1838 // In this loop, we must only follow those oops directly embedded in 1839 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1840 assert(1 == (r->oop_is_immediate()) + 1841 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1842 "oop must be found in exactly one place"); 1843 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1844 f->do_oop(r->oop_addr()); 1845 } 1846 } 1847 } 1848 1849 // Scopes 1850 // This includes oop constants not inlined in the code stream. 1851 for (oop* p = oops_begin(); p < oops_end(); p++) { 1852 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1853 f->do_oop(p); 1854 } 1855 } 1856 1857 #define NMETHOD_SENTINEL ((nmethod*)badAddress) 1858 1859 nmethod* volatile nmethod::_oops_do_mark_nmethods; 1860 1861 // An nmethod is "marked" if its _mark_link is set non-null. 1862 // Even if it is the end of the linked list, it will have a non-null link value, 1863 // as long as it is on the list. 1864 // This code must be MP safe, because it is used from parallel GC passes. 1865 bool nmethod::test_set_oops_do_mark() { 1866 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called"); 1867 nmethod* observed_mark_link = _oops_do_mark_link; 1868 if (observed_mark_link == NULL) { 1869 // Claim this nmethod for this thread to mark. 1870 observed_mark_link = (nmethod*) 1871 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL); 1872 if (observed_mark_link == NULL) { 1873 1874 // Atomically append this nmethod (now claimed) to the head of the list: 1875 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods; 1876 for (;;) { 1877 nmethod* required_mark_nmethods = observed_mark_nmethods; 1878 _oops_do_mark_link = required_mark_nmethods; 1879 observed_mark_nmethods = (nmethod*) 1880 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods); 1881 if (observed_mark_nmethods == required_mark_nmethods) 1882 break; 1883 } 1884 // Mark was clear when we first saw this guy. 1885 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark")); 1886 return false; 1887 } 1888 } 1889 // On fall through, another racing thread marked this nmethod before we did. 1890 return true; 1891 } 1892 1893 void nmethod::oops_do_marking_prologue() { 1894 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue")); 1895 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row"); 1896 // We use cmpxchg_ptr instead of regular assignment here because the user 1897 // may fork a bunch of threads, and we need them all to see the same state. 1898 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL); 1899 guarantee(observed == NULL, "no races in this sequential code"); 1900 } 1901 1902 void nmethod::oops_do_marking_epilogue() { 1903 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row"); 1904 nmethod* cur = _oops_do_mark_nmethods; 1905 while (cur != NMETHOD_SENTINEL) { 1906 assert(cur != NULL, "not NULL-terminated"); 1907 nmethod* next = cur->_oops_do_mark_link; 1908 cur->_oops_do_mark_link = NULL; 1909 cur->fix_oop_relocations(); 1910 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark")); 1911 cur = next; 1912 } 1913 void* required = _oops_do_mark_nmethods; 1914 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required); 1915 guarantee(observed == required, "no races in this sequential code"); 1916 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]")); 1917 } 1918 1919 class DetectScavengeRoot: public OopClosure { 1920 bool _detected_scavenge_root; 1921 public: 1922 DetectScavengeRoot() : _detected_scavenge_root(false) 1923 { NOT_PRODUCT(_print_nm = NULL); } 1924 bool detected_scavenge_root() { return _detected_scavenge_root; } 1925 virtual void do_oop(oop* p) { 1926 if ((*p) != NULL && (*p)->is_scavengable()) { 1927 NOT_PRODUCT(maybe_print(p)); 1928 _detected_scavenge_root = true; 1929 } 1930 } 1931 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 1932 1933 #ifndef PRODUCT 1934 nmethod* _print_nm; 1935 void maybe_print(oop* p) { 1936 if (_print_nm == NULL) return; 1937 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root"); 1938 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")", 1939 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm), 1940 (intptr_t)(*p), (intptr_t)p); 1941 (*p)->print(); 1942 } 1943 #endif //PRODUCT 1944 }; 1945 1946 bool nmethod::detect_scavenge_root_oops() { 1947 DetectScavengeRoot detect_scavenge_root; 1948 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this); 1949 oops_do(&detect_scavenge_root); 1950 return detect_scavenge_root.detected_scavenge_root(); 1951 } 1952 1953 // Method that knows how to preserve outgoing arguments at call. This method must be 1954 // called with a frame corresponding to a Java invoke 1955 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { 1956 #ifndef SHARK 1957 if (!method()->is_native()) { 1958 SimpleScopeDesc ssd(this, fr.pc()); 1959 Bytecode_invoke call(ssd.method(), ssd.bci()); 1960 // compiled invokedynamic call sites have an implicit receiver at 1961 // resolution time, so make sure it gets GC'ed. 1962 bool has_receiver = !call.is_invokestatic(); 1963 Symbol* signature = call.signature(); 1964 fr.oops_compiled_arguments_do(signature, has_receiver, reg_map, f); 1965 } 1966 #endif // !SHARK 1967 } 1968 1969 1970 oop nmethod::embeddedOop_at(u_char* p) { 1971 RelocIterator iter(this, p, p + 1); 1972 while (iter.next()) 1973 if (iter.type() == relocInfo::oop_type) { 1974 return iter.oop_reloc()->oop_value(); 1975 } 1976 return NULL; 1977 } 1978 1979 1980 inline bool includes(void* p, void* from, void* to) { 1981 return from <= p && p < to; 1982 } 1983 1984 1985 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) { 1986 assert(count >= 2, "must be sentinel values, at least"); 1987 1988 #ifdef ASSERT 1989 // must be sorted and unique; we do a binary search in find_pc_desc() 1990 int prev_offset = pcs[0].pc_offset(); 1991 assert(prev_offset == PcDesc::lower_offset_limit, 1992 "must start with a sentinel"); 1993 for (int i = 1; i < count; i++) { 1994 int this_offset = pcs[i].pc_offset(); 1995 assert(this_offset > prev_offset, "offsets must be sorted"); 1996 prev_offset = this_offset; 1997 } 1998 assert(prev_offset == PcDesc::upper_offset_limit, 1999 "must end with a sentinel"); 2000 #endif //ASSERT 2001 2002 // Search for MethodHandle invokes and tag the nmethod. 2003 for (int i = 0; i < count; i++) { 2004 if (pcs[i].is_method_handle_invoke()) { 2005 set_has_method_handle_invokes(true); 2006 break; 2007 } 2008 } 2009 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler"); 2010 2011 int size = count * sizeof(PcDesc); 2012 assert(scopes_pcs_size() >= size, "oob"); 2013 memcpy(scopes_pcs_begin(), pcs, size); 2014 2015 // Adjust the final sentinel downward. 2016 PcDesc* last_pc = &scopes_pcs_begin()[count-1]; 2017 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity"); 2018 last_pc->set_pc_offset(content_size() + 1); 2019 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { 2020 // Fill any rounding gaps with copies of the last record. 2021 last_pc[1] = last_pc[0]; 2022 } 2023 // The following assert could fail if sizeof(PcDesc) is not 2024 // an integral multiple of oopSize (the rounding term). 2025 // If it fails, change the logic to always allocate a multiple 2026 // of sizeof(PcDesc), and fill unused words with copies of *last_pc. 2027 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly"); 2028 } 2029 2030 void nmethod::copy_scopes_data(u_char* buffer, int size) { 2031 assert(scopes_data_size() >= size, "oob"); 2032 memcpy(scopes_data_begin(), buffer, size); 2033 } 2034 2035 2036 #ifdef ASSERT 2037 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) { 2038 PcDesc* lower = nm->scopes_pcs_begin(); 2039 PcDesc* upper = nm->scopes_pcs_end(); 2040 lower += 1; // exclude initial sentinel 2041 PcDesc* res = NULL; 2042 for (PcDesc* p = lower; p < upper; p++) { 2043 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc 2044 if (match_desc(p, pc_offset, approximate)) { 2045 if (res == NULL) 2046 res = p; 2047 else 2048 res = (PcDesc*) badAddress; 2049 } 2050 } 2051 return res; 2052 } 2053 #endif 2054 2055 2056 // Finds a PcDesc with real-pc equal to "pc" 2057 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) { 2058 address base_address = code_begin(); 2059 if ((pc < base_address) || 2060 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { 2061 return NULL; // PC is wildly out of range 2062 } 2063 int pc_offset = (int) (pc - base_address); 2064 2065 // Check the PcDesc cache if it contains the desired PcDesc 2066 // (This as an almost 100% hit rate.) 2067 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); 2068 if (res != NULL) { 2069 assert(res == linear_search(this, pc_offset, approximate), "cache ok"); 2070 return res; 2071 } 2072 2073 // Fallback algorithm: quasi-linear search for the PcDesc 2074 // Find the last pc_offset less than the given offset. 2075 // The successor must be the required match, if there is a match at all. 2076 // (Use a fixed radix to avoid expensive affine pointer arithmetic.) 2077 PcDesc* lower = scopes_pcs_begin(); 2078 PcDesc* upper = scopes_pcs_end(); 2079 upper -= 1; // exclude final sentinel 2080 if (lower >= upper) return NULL; // native method; no PcDescs at all 2081 2082 #define assert_LU_OK \ 2083 /* invariant on lower..upper during the following search: */ \ 2084 assert(lower->pc_offset() < pc_offset, "sanity"); \ 2085 assert(upper->pc_offset() >= pc_offset, "sanity") 2086 assert_LU_OK; 2087 2088 // Use the last successful return as a split point. 2089 PcDesc* mid = _pc_desc_cache.last_pc_desc(); 2090 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2091 if (mid->pc_offset() < pc_offset) { 2092 lower = mid; 2093 } else { 2094 upper = mid; 2095 } 2096 2097 // Take giant steps at first (4096, then 256, then 16, then 1) 2098 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); 2099 const int RADIX = (1 << LOG2_RADIX); 2100 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { 2101 while ((mid = lower + step) < upper) { 2102 assert_LU_OK; 2103 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2104 if (mid->pc_offset() < pc_offset) { 2105 lower = mid; 2106 } else { 2107 upper = mid; 2108 break; 2109 } 2110 } 2111 assert_LU_OK; 2112 } 2113 2114 // Sneak up on the value with a linear search of length ~16. 2115 while (true) { 2116 assert_LU_OK; 2117 mid = lower + 1; 2118 NOT_PRODUCT(++nmethod_stats.pc_desc_searches); 2119 if (mid->pc_offset() < pc_offset) { 2120 lower = mid; 2121 } else { 2122 upper = mid; 2123 break; 2124 } 2125 } 2126 #undef assert_LU_OK 2127 2128 if (match_desc(upper, pc_offset, approximate)) { 2129 assert(upper == linear_search(this, pc_offset, approximate), "search ok"); 2130 _pc_desc_cache.add_pc_desc(upper); 2131 return upper; 2132 } else { 2133 assert(NULL == linear_search(this, pc_offset, approximate), "search ok"); 2134 return NULL; 2135 } 2136 } 2137 2138 2139 bool nmethod::check_all_dependencies() { 2140 bool found_check = false; 2141 // wholesale check of all dependencies 2142 for (Dependencies::DepStream deps(this); deps.next(); ) { 2143 if (deps.check_dependency() != NULL) { 2144 found_check = true; 2145 NOT_DEBUG(break); 2146 } 2147 } 2148 return found_check; // tell caller if we found anything 2149 } 2150 2151 bool nmethod::check_dependency_on(DepChange& changes) { 2152 // What has happened: 2153 // 1) a new class dependee has been added 2154 // 2) dependee and all its super classes have been marked 2155 bool found_check = false; // set true if we are upset 2156 for (Dependencies::DepStream deps(this); deps.next(); ) { 2157 // Evaluate only relevant dependencies. 2158 if (deps.spot_check_dependency_at(changes) != NULL) { 2159 found_check = true; 2160 NOT_DEBUG(break); 2161 } 2162 } 2163 return found_check; 2164 } 2165 2166 bool nmethod::is_evol_dependent_on(Klass* dependee) { 2167 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee); 2168 Array<Method*>* dependee_methods = dependee_ik->methods(); 2169 for (Dependencies::DepStream deps(this); deps.next(); ) { 2170 if (deps.type() == Dependencies::evol_method) { 2171 Method* method = deps.method_argument(0); 2172 for (int j = 0; j < dependee_methods->length(); j++) { 2173 if (dependee_methods->at(j) == method) { 2174 // RC_TRACE macro has an embedded ResourceMark 2175 RC_TRACE(0x01000000, 2176 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)", 2177 _method->method_holder()->external_name(), 2178 _method->name()->as_C_string(), 2179 _method->signature()->as_C_string(), compile_id(), 2180 method->method_holder()->external_name(), 2181 method->name()->as_C_string(), 2182 method->signature()->as_C_string())); 2183 if (TraceDependencies || LogCompilation) 2184 deps.log_dependency(dependee); 2185 return true; 2186 } 2187 } 2188 } 2189 } 2190 return false; 2191 } 2192 2193 // Called from mark_for_deoptimization, when dependee is invalidated. 2194 bool nmethod::is_dependent_on_method(Method* dependee) { 2195 for (Dependencies::DepStream deps(this); deps.next(); ) { 2196 if (deps.type() != Dependencies::evol_method) 2197 continue; 2198 Method* method = deps.method_argument(0); 2199 if (method == dependee) return true; 2200 } 2201 return false; 2202 } 2203 2204 2205 bool nmethod::is_patchable_at(address instr_addr) { 2206 assert(insts_contains(instr_addr), "wrong nmethod used"); 2207 if (is_zombie()) { 2208 // a zombie may never be patched 2209 return false; 2210 } 2211 return true; 2212 } 2213 2214 2215 address nmethod::continuation_for_implicit_exception(address pc) { 2216 // Exception happened outside inline-cache check code => we are inside 2217 // an active nmethod => use cpc to determine a return address 2218 int exception_offset = pc - code_begin(); 2219 int cont_offset = ImplicitExceptionTable(this).at( exception_offset ); 2220 #ifdef ASSERT 2221 if (cont_offset == 0) { 2222 Thread* thread = ThreadLocalStorage::get_thread_slow(); 2223 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY 2224 HandleMark hm(thread); 2225 ResourceMark rm(thread); 2226 CodeBlob* cb = CodeCache::find_blob(pc); 2227 assert(cb != NULL && cb == this, ""); 2228 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc); 2229 print(); 2230 method()->print_codes(); 2231 print_code(); 2232 print_pcs(); 2233 } 2234 #endif 2235 if (cont_offset == 0) { 2236 // Let the normal error handling report the exception 2237 return NULL; 2238 } 2239 return code_begin() + cont_offset; 2240 } 2241 2242 2243 2244 void nmethod_init() { 2245 // make sure you didn't forget to adjust the filler fields 2246 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word"); 2247 } 2248 2249 2250 //------------------------------------------------------------------------------------------- 2251 2252 2253 // QQQ might we make this work from a frame?? 2254 nmethodLocker::nmethodLocker(address pc) { 2255 CodeBlob* cb = CodeCache::find_blob(pc); 2256 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found"); 2257 _nm = (nmethod*)cb; 2258 lock_nmethod(_nm); 2259 } 2260 2261 // Only JvmtiDeferredEvent::compiled_method_unload_event() 2262 // should pass zombie_ok == true. 2263 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) { 2264 if (nm == NULL) return; 2265 Atomic::inc(&nm->_lock_count); 2266 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method"); 2267 } 2268 2269 void nmethodLocker::unlock_nmethod(nmethod* nm) { 2270 if (nm == NULL) return; 2271 Atomic::dec(&nm->_lock_count); 2272 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock"); 2273 } 2274 2275 2276 // ----------------------------------------------------------------------------- 2277 // nmethod::get_deopt_original_pc 2278 // 2279 // Return the original PC for the given PC if: 2280 // (a) the given PC belongs to a nmethod and 2281 // (b) it is a deopt PC 2282 address nmethod::get_deopt_original_pc(const frame* fr) { 2283 if (fr->cb() == NULL) return NULL; 2284 2285 nmethod* nm = fr->cb()->as_nmethod_or_null(); 2286 if (nm != NULL && nm->is_deopt_pc(fr->pc())) 2287 return nm->get_original_pc(fr); 2288 2289 return NULL; 2290 } 2291 2292 2293 // ----------------------------------------------------------------------------- 2294 // MethodHandle 2295 2296 bool nmethod::is_method_handle_return(address return_pc) { 2297 if (!has_method_handle_invokes()) return false; 2298 PcDesc* pd = pc_desc_at(return_pc); 2299 if (pd == NULL) 2300 return false; 2301 return pd->is_method_handle_invoke(); 2302 } 2303 2304 2305 // ----------------------------------------------------------------------------- 2306 // Verification 2307 2308 class VerifyOopsClosure: public OopClosure { 2309 nmethod* _nm; 2310 bool _ok; 2311 public: 2312 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } 2313 bool ok() { return _ok; } 2314 virtual void do_oop(oop* p) { 2315 if ((*p) == NULL || (*p)->is_oop()) return; 2316 if (_ok) { 2317 _nm->print_nmethod(true); 2318 _ok = false; 2319 } 2320 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2321 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2322 } 2323 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2324 }; 2325 2326 void nmethod::verify() { 2327 2328 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant 2329 // seems odd. 2330 2331 if( is_zombie() || is_not_entrant() ) 2332 return; 2333 2334 // Make sure all the entry points are correctly aligned for patching. 2335 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point()); 2336 2337 // assert(method()->is_oop(), "must be valid"); 2338 2339 ResourceMark rm; 2340 2341 if (!CodeCache::contains(this)) { 2342 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this)); 2343 } 2344 2345 if(is_native_method() ) 2346 return; 2347 2348 nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); 2349 if (nm != this) { 2350 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", 2351 this)); 2352 } 2353 2354 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2355 if (! p->verify(this)) { 2356 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this); 2357 } 2358 } 2359 2360 VerifyOopsClosure voc(this); 2361 oops_do(&voc); 2362 assert(voc.ok(), "embedded oops must be OK"); 2363 verify_scavenge_root_oops(); 2364 2365 verify_scopes(); 2366 } 2367 2368 2369 void nmethod::verify_interrupt_point(address call_site) { 2370 // This code does not work in release mode since 2371 // owns_lock only is available in debug mode. 2372 CompiledIC* ic = NULL; 2373 Thread *cur = Thread::current(); 2374 if (CompiledIC_lock->owner() == cur || 2375 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) && 2376 SafepointSynchronize::is_at_safepoint())) { 2377 ic = CompiledIC_at(this, call_site); 2378 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 2379 } else { 2380 MutexLocker ml_verify (CompiledIC_lock); 2381 ic = CompiledIC_at(this, call_site); 2382 } 2383 PcDesc* pd = pc_desc_at(ic->end_of_call()); 2384 assert(pd != NULL, "PcDesc must exist"); 2385 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(), 2386 pd->obj_decode_offset(), pd->should_reexecute(), 2387 pd->return_oop()); 2388 !sd->is_top(); sd = sd->sender()) { 2389 sd->verify(); 2390 } 2391 } 2392 2393 void nmethod::verify_scopes() { 2394 if( !method() ) return; // Runtime stubs have no scope 2395 if (method()->is_native()) return; // Ignore stub methods. 2396 // iterate through all interrupt point 2397 // and verify the debug information is valid. 2398 RelocIterator iter((nmethod*)this); 2399 while (iter.next()) { 2400 address stub = NULL; 2401 switch (iter.type()) { 2402 case relocInfo::virtual_call_type: 2403 verify_interrupt_point(iter.addr()); 2404 break; 2405 case relocInfo::opt_virtual_call_type: 2406 stub = iter.opt_virtual_call_reloc()->static_stub(); 2407 verify_interrupt_point(iter.addr()); 2408 break; 2409 case relocInfo::static_call_type: 2410 stub = iter.static_call_reloc()->static_stub(); 2411 //verify_interrupt_point(iter.addr()); 2412 break; 2413 case relocInfo::runtime_call_type: 2414 address destination = iter.reloc()->value(); 2415 // Right now there is no way to find out which entries support 2416 // an interrupt point. It would be nice if we had this 2417 // information in a table. 2418 break; 2419 } 2420 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section"); 2421 } 2422 } 2423 2424 2425 // ----------------------------------------------------------------------------- 2426 // Non-product code 2427 #ifndef PRODUCT 2428 2429 class DebugScavengeRoot: public OopClosure { 2430 nmethod* _nm; 2431 bool _ok; 2432 public: 2433 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { } 2434 bool ok() { return _ok; } 2435 virtual void do_oop(oop* p) { 2436 if ((*p) == NULL || !(*p)->is_scavengable()) return; 2437 if (_ok) { 2438 _nm->print_nmethod(true); 2439 _ok = false; 2440 } 2441 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)", 2442 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm)); 2443 (*p)->print(); 2444 } 2445 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2446 }; 2447 2448 void nmethod::verify_scavenge_root_oops() { 2449 if (!on_scavenge_root_list()) { 2450 // Actually look inside, to verify the claim that it's clean. 2451 DebugScavengeRoot debug_scavenge_root(this); 2452 oops_do(&debug_scavenge_root); 2453 if (!debug_scavenge_root.ok()) 2454 fatal("found an unadvertised bad scavengable oop in the code cache"); 2455 } 2456 assert(scavenge_root_not_marked(), ""); 2457 } 2458 2459 #endif // PRODUCT 2460 2461 // Printing operations 2462 2463 void nmethod::print() const { 2464 ResourceMark rm; 2465 ttyLocker ttyl; // keep the following output all in one block 2466 2467 tty->print("Compiled method "); 2468 2469 if (is_compiled_by_c1()) { 2470 tty->print("(c1) "); 2471 } else if (is_compiled_by_c2()) { 2472 tty->print("(c2) "); 2473 } else if (is_compiled_by_shark()) { 2474 tty->print("(shark) "); 2475 } else { 2476 tty->print("(nm) "); 2477 } 2478 2479 print_on(tty, NULL); 2480 2481 if (WizardMode) { 2482 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this); 2483 tty->print(" for method " INTPTR_FORMAT , (address)method()); 2484 tty->print(" { "); 2485 if (is_in_use()) tty->print("in_use "); 2486 if (is_not_entrant()) tty->print("not_entrant "); 2487 if (is_zombie()) tty->print("zombie "); 2488 if (is_unloaded()) tty->print("unloaded "); 2489 if (on_scavenge_root_list()) tty->print("scavenge_root "); 2490 tty->print_cr("}:"); 2491 } 2492 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2493 (address)this, 2494 (address)this + size(), 2495 size()); 2496 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2497 relocation_begin(), 2498 relocation_end(), 2499 relocation_size()); 2500 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2501 consts_begin(), 2502 consts_end(), 2503 consts_size()); 2504 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2505 insts_begin(), 2506 insts_end(), 2507 insts_size()); 2508 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2509 stub_begin(), 2510 stub_end(), 2511 stub_size()); 2512 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2513 oops_begin(), 2514 oops_end(), 2515 oops_size()); 2516 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2517 metadata_begin(), 2518 metadata_end(), 2519 metadata_size()); 2520 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2521 scopes_data_begin(), 2522 scopes_data_end(), 2523 scopes_data_size()); 2524 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2525 scopes_pcs_begin(), 2526 scopes_pcs_end(), 2527 scopes_pcs_size()); 2528 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2529 dependencies_begin(), 2530 dependencies_end(), 2531 dependencies_size()); 2532 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2533 handler_table_begin(), 2534 handler_table_end(), 2535 handler_table_size()); 2536 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2537 nul_chk_table_begin(), 2538 nul_chk_table_end(), 2539 nul_chk_table_size()); 2540 } 2541 2542 void nmethod::print_code() { 2543 HandleMark hm; 2544 ResourceMark m; 2545 Disassembler::decode(this); 2546 } 2547 2548 2549 #ifndef PRODUCT 2550 2551 void nmethod::print_scopes() { 2552 // Find the first pc desc for all scopes in the code and print it. 2553 ResourceMark rm; 2554 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2555 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) 2556 continue; 2557 2558 ScopeDesc* sd = scope_desc_at(p->real_pc(this)); 2559 sd->print_on(tty, p); 2560 } 2561 } 2562 2563 void nmethod::print_dependencies() { 2564 ResourceMark rm; 2565 ttyLocker ttyl; // keep the following output all in one block 2566 tty->print_cr("Dependencies:"); 2567 for (Dependencies::DepStream deps(this); deps.next(); ) { 2568 deps.print_dependency(); 2569 Klass* ctxk = deps.context_type(); 2570 if (ctxk != NULL) { 2571 Klass* k = Klass::cast(ctxk); 2572 if (k->oop_is_instance() && ((InstanceKlass*)k)->is_dependent_nmethod(this)) { 2573 tty->print_cr(" [nmethod<=klass]%s", k->external_name()); 2574 } 2575 } 2576 deps.log_dependency(); // put it into the xml log also 2577 } 2578 } 2579 2580 2581 void nmethod::print_relocations() { 2582 ResourceMark m; // in case methods get printed via the debugger 2583 tty->print_cr("relocations:"); 2584 RelocIterator iter(this); 2585 iter.print(); 2586 if (UseRelocIndex) { 2587 jint* index_end = (jint*)relocation_end() - 1; 2588 jint index_size = *index_end; 2589 jint* index_start = (jint*)( (address)index_end - index_size ); 2590 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size); 2591 if (index_size > 0) { 2592 jint* ip; 2593 for (ip = index_start; ip+2 <= index_end; ip += 2) 2594 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT, 2595 ip[0], 2596 ip[1], 2597 header_end()+ip[0], 2598 relocation_begin()-1+ip[1]); 2599 for (; ip < index_end; ip++) 2600 tty->print_cr(" (%d ?)", ip[0]); 2601 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip++); 2602 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip); 2603 } 2604 } 2605 } 2606 2607 2608 void nmethod::print_pcs() { 2609 ResourceMark m; // in case methods get printed via debugger 2610 tty->print_cr("pc-bytecode offsets:"); 2611 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2612 p->print(this); 2613 } 2614 } 2615 2616 #endif // PRODUCT 2617 2618 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) { 2619 RelocIterator iter(this, begin, end); 2620 bool have_one = false; 2621 while (iter.next()) { 2622 have_one = true; 2623 switch (iter.type()) { 2624 case relocInfo::none: return "no_reloc"; 2625 case relocInfo::oop_type: { 2626 stringStream st; 2627 oop_Relocation* r = iter.oop_reloc(); 2628 oop obj = r->oop_value(); 2629 st.print("oop("); 2630 if (obj == NULL) st.print("NULL"); 2631 else obj->print_value_on(&st); 2632 st.print(")"); 2633 return st.as_string(); 2634 } 2635 case relocInfo::metadata_type: { 2636 stringStream st; 2637 metadata_Relocation* r = iter.metadata_reloc(); 2638 Metadata* obj = r->metadata_value(); 2639 st.print("metadata("); 2640 if (obj == NULL) st.print("NULL"); 2641 else obj->print_value_on(&st); 2642 st.print(")"); 2643 return st.as_string(); 2644 } 2645 case relocInfo::virtual_call_type: return "virtual_call"; 2646 case relocInfo::opt_virtual_call_type: return "optimized virtual_call"; 2647 case relocInfo::static_call_type: return "static_call"; 2648 case relocInfo::static_stub_type: return "static_stub"; 2649 case relocInfo::runtime_call_type: return "runtime_call"; 2650 case relocInfo::external_word_type: return "external_word"; 2651 case relocInfo::internal_word_type: return "internal_word"; 2652 case relocInfo::section_word_type: return "section_word"; 2653 case relocInfo::poll_type: return "poll"; 2654 case relocInfo::poll_return_type: return "poll_return"; 2655 case relocInfo::type_mask: return "type_bit_mask"; 2656 } 2657 } 2658 return have_one ? "other" : NULL; 2659 } 2660 2661 // Return a the last scope in (begin..end] 2662 ScopeDesc* nmethod::scope_desc_in(address begin, address end) { 2663 PcDesc* p = pc_desc_near(begin+1); 2664 if (p != NULL && p->real_pc(this) <= end) { 2665 return new ScopeDesc(this, p->scope_decode_offset(), 2666 p->obj_decode_offset(), p->should_reexecute(), 2667 p->return_oop()); 2668 } 2669 return NULL; 2670 } 2671 2672 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) { 2673 if (block_begin == entry_point()) stream->print_cr("[Entry Point]"); 2674 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]"); 2675 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]"); 2676 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]"); 2677 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]"); 2678 2679 if (has_method_handle_invokes()) 2680 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]"); 2681 2682 if (block_begin == consts_begin()) stream->print_cr("[Constants]"); 2683 2684 if (block_begin == entry_point()) { 2685 methodHandle m = method(); 2686 if (m.not_null()) { 2687 stream->print(" # "); 2688 m->print_value_on(stream); 2689 stream->cr(); 2690 } 2691 if (m.not_null() && !is_osr_method()) { 2692 ResourceMark rm; 2693 int sizeargs = m->size_of_parameters(); 2694 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs); 2695 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs); 2696 { 2697 int sig_index = 0; 2698 if (!m->is_static()) 2699 sig_bt[sig_index++] = T_OBJECT; // 'this' 2700 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) { 2701 BasicType t = ss.type(); 2702 sig_bt[sig_index++] = t; 2703 if (type2size[t] == 2) { 2704 sig_bt[sig_index++] = T_VOID; 2705 } else { 2706 assert(type2size[t] == 1, "size is 1 or 2"); 2707 } 2708 } 2709 assert(sig_index == sizeargs, ""); 2710 } 2711 const char* spname = "sp"; // make arch-specific? 2712 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false); 2713 int stack_slot_offset = this->frame_size() * wordSize; 2714 int tab1 = 14, tab2 = 24; 2715 int sig_index = 0; 2716 int arg_index = (m->is_static() ? 0 : -1); 2717 bool did_old_sp = false; 2718 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) { 2719 bool at_this = (arg_index == -1); 2720 bool at_old_sp = false; 2721 BasicType t = (at_this ? T_OBJECT : ss.type()); 2722 assert(t == sig_bt[sig_index], "sigs in sync"); 2723 if (at_this) 2724 stream->print(" # this: "); 2725 else 2726 stream->print(" # parm%d: ", arg_index); 2727 stream->move_to(tab1); 2728 VMReg fst = regs[sig_index].first(); 2729 VMReg snd = regs[sig_index].second(); 2730 if (fst->is_reg()) { 2731 stream->print("%s", fst->name()); 2732 if (snd->is_valid()) { 2733 stream->print(":%s", snd->name()); 2734 } 2735 } else if (fst->is_stack()) { 2736 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset; 2737 if (offset == stack_slot_offset) at_old_sp = true; 2738 stream->print("[%s+0x%x]", spname, offset); 2739 } else { 2740 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd); 2741 } 2742 stream->print(" "); 2743 stream->move_to(tab2); 2744 stream->print("= "); 2745 if (at_this) { 2746 m->method_holder()->print_value_on(stream); 2747 } else { 2748 bool did_name = false; 2749 if (!at_this && ss.is_object()) { 2750 Symbol* name = ss.as_symbol_or_null(); 2751 if (name != NULL) { 2752 name->print_value_on(stream); 2753 did_name = true; 2754 } 2755 } 2756 if (!did_name) 2757 stream->print("%s", type2name(t)); 2758 } 2759 if (at_old_sp) { 2760 stream->print(" (%s of caller)", spname); 2761 did_old_sp = true; 2762 } 2763 stream->cr(); 2764 sig_index += type2size[t]; 2765 arg_index += 1; 2766 if (!at_this) ss.next(); 2767 } 2768 if (!did_old_sp) { 2769 stream->print(" # "); 2770 stream->move_to(tab1); 2771 stream->print("[%s+0x%x]", spname, stack_slot_offset); 2772 stream->print(" (%s of caller)", spname); 2773 stream->cr(); 2774 } 2775 } 2776 } 2777 } 2778 2779 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) { 2780 // First, find an oopmap in (begin, end]. 2781 // We use the odd half-closed interval so that oop maps and scope descs 2782 // which are tied to the byte after a call are printed with the call itself. 2783 address base = code_begin(); 2784 OopMapSet* oms = oop_maps(); 2785 if (oms != NULL) { 2786 for (int i = 0, imax = oms->size(); i < imax; i++) { 2787 OopMap* om = oms->at(i); 2788 address pc = base + om->offset(); 2789 if (pc > begin) { 2790 if (pc <= end) { 2791 st->move_to(column); 2792 st->print("; "); 2793 om->print_on(st); 2794 } 2795 break; 2796 } 2797 } 2798 } 2799 2800 // Print any debug info present at this pc. 2801 ScopeDesc* sd = scope_desc_in(begin, end); 2802 if (sd != NULL) { 2803 st->move_to(column); 2804 if (sd->bci() == SynchronizationEntryBCI) { 2805 st->print(";*synchronization entry"); 2806 } else { 2807 if (sd->method() == NULL) { 2808 st->print("method is NULL"); 2809 } else if (sd->method()->is_native()) { 2810 st->print("method is native"); 2811 } else { 2812 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci()); 2813 st->print(";*%s", Bytecodes::name(bc)); 2814 switch (bc) { 2815 case Bytecodes::_invokevirtual: 2816 case Bytecodes::_invokespecial: 2817 case Bytecodes::_invokestatic: 2818 case Bytecodes::_invokeinterface: 2819 { 2820 Bytecode_invoke invoke(sd->method(), sd->bci()); 2821 st->print(" "); 2822 if (invoke.name() != NULL) 2823 invoke.name()->print_symbol_on(st); 2824 else 2825 st->print("<UNKNOWN>"); 2826 break; 2827 } 2828 case Bytecodes::_getfield: 2829 case Bytecodes::_putfield: 2830 case Bytecodes::_getstatic: 2831 case Bytecodes::_putstatic: 2832 { 2833 Bytecode_field field(sd->method(), sd->bci()); 2834 st->print(" "); 2835 if (field.name() != NULL) 2836 field.name()->print_symbol_on(st); 2837 else 2838 st->print("<UNKNOWN>"); 2839 } 2840 } 2841 } 2842 } 2843 2844 // Print all scopes 2845 for (;sd != NULL; sd = sd->sender()) { 2846 st->move_to(column); 2847 st->print("; -"); 2848 if (sd->method() == NULL) { 2849 st->print("method is NULL"); 2850 } else { 2851 sd->method()->print_short_name(st); 2852 } 2853 int lineno = sd->method()->line_number_from_bci(sd->bci()); 2854 if (lineno != -1) { 2855 st->print("@%d (line %d)", sd->bci(), lineno); 2856 } else { 2857 st->print("@%d", sd->bci()); 2858 } 2859 st->cr(); 2860 } 2861 } 2862 2863 // Print relocation information 2864 const char* str = reloc_string_for(begin, end); 2865 if (str != NULL) { 2866 if (sd != NULL) st->cr(); 2867 st->move_to(column); 2868 st->print("; {%s}", str); 2869 } 2870 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin()); 2871 if (cont_offset != 0) { 2872 st->move_to(column); 2873 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset); 2874 } 2875 2876 } 2877 2878 #ifndef PRODUCT 2879 2880 void nmethod::print_value_on(outputStream* st) const { 2881 st->print("nmethod"); 2882 print_on(st, NULL); 2883 } 2884 2885 void nmethod::print_calls(outputStream* st) { 2886 RelocIterator iter(this); 2887 while (iter.next()) { 2888 switch (iter.type()) { 2889 case relocInfo::virtual_call_type: 2890 case relocInfo::opt_virtual_call_type: { 2891 VerifyMutexLocker mc(CompiledIC_lock); 2892 CompiledIC_at(iter.reloc())->print(); 2893 break; 2894 } 2895 case relocInfo::static_call_type: 2896 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr()); 2897 compiledStaticCall_at(iter.reloc())->print(); 2898 break; 2899 } 2900 } 2901 } 2902 2903 void nmethod::print_handler_table() { 2904 ExceptionHandlerTable(this).print(); 2905 } 2906 2907 void nmethod::print_nul_chk_table() { 2908 ImplicitExceptionTable(this).print(code_begin()); 2909 } 2910 2911 void nmethod::print_statistics() { 2912 ttyLocker ttyl; 2913 if (xtty != NULL) xtty->head("statistics type='nmethod'"); 2914 nmethod_stats.print_native_nmethod_stats(); 2915 nmethod_stats.print_nmethod_stats(); 2916 DebugInformationRecorder::print_statistics(); 2917 nmethod_stats.print_pc_stats(); 2918 Dependencies::print_statistics(); 2919 if (xtty != NULL) xtty->tail("statistics"); 2920 } 2921 2922 #endif // PRODUCT