1 /* 2 * Copyright (c) 1997, 2016, 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/nativeInst.hpp" 30 #include "code/nmethod.hpp" 31 #include "code/scopeDesc.hpp" 32 #include "compiler/abstractCompiler.hpp" 33 #include "compiler/compileBroker.hpp" 34 #include "compiler/compileLog.hpp" 35 #include "compiler/compilerDirectives.hpp" 36 #include "compiler/directivesParser.hpp" 37 #include "compiler/disassembler.hpp" 38 #include "interpreter/bytecode.hpp" 39 #include "oops/methodData.hpp" 40 #include "oops/oop.inline.hpp" 41 #include "prims/jvmtiRedefineClassesTrace.hpp" 42 #include "prims/jvmtiImpl.hpp" 43 #include "runtime/atomic.inline.hpp" 44 #include "runtime/orderAccess.inline.hpp" 45 #include "runtime/os.hpp" 46 #include "runtime/sharedRuntime.hpp" 47 #include "runtime/sweeper.hpp" 48 #include "utilities/resourceHash.hpp" 49 #include "utilities/dtrace.hpp" 50 #include "utilities/events.hpp" 51 #include "utilities/xmlstream.hpp" 52 #include "logging/log.hpp" 53 #ifdef TARGET_ARCH_x86 54 # include "nativeInst_x86.hpp" 55 #endif 56 #ifdef TARGET_ARCH_sparc 57 # include "nativeInst_sparc.hpp" 58 #endif 59 #ifdef TARGET_ARCH_zero 60 # include "nativeInst_zero.hpp" 61 #endif 62 #ifdef TARGET_ARCH_arm 63 # include "nativeInst_arm.hpp" 64 #endif 65 #ifdef TARGET_ARCH_ppc 66 # include "nativeInst_ppc.hpp" 67 #endif 68 #ifdef SHARK 69 #include "shark/sharkCompiler.hpp" 70 #endif 71 #if INCLUDE_JVMCI 72 #include "jvmci/jvmciJavaClasses.hpp" 73 #endif 74 75 unsigned char nmethod::_global_unloading_clock = 0; 76 77 #ifdef DTRACE_ENABLED 78 79 // Only bother with this argument setup if dtrace is available 80 81 #define DTRACE_METHOD_UNLOAD_PROBE(method) \ 82 { \ 83 Method* m = (method); \ 84 if (m != NULL) { \ 85 Symbol* klass_name = m->klass_name(); \ 86 Symbol* name = m->name(); \ 87 Symbol* signature = m->signature(); \ 88 HOTSPOT_COMPILED_METHOD_UNLOAD( \ 89 (char *) klass_name->bytes(), klass_name->utf8_length(), \ 90 (char *) name->bytes(), name->utf8_length(), \ 91 (char *) signature->bytes(), signature->utf8_length()); \ 92 } \ 93 } 94 95 #else // ndef DTRACE_ENABLED 96 97 #define DTRACE_METHOD_UNLOAD_PROBE(method) 98 99 #endif 100 101 bool nmethod::is_compiled_by_c1() const { 102 if (compiler() == NULL) { 103 return false; 104 } 105 return compiler()->is_c1(); 106 } 107 bool nmethod::is_compiled_by_jvmci() const { 108 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing 109 if (is_native_method()) return false; 110 return compiler()->is_jvmci(); 111 } 112 bool nmethod::is_compiled_by_c2() const { 113 if (compiler() == NULL) { 114 return false; 115 } 116 return compiler()->is_c2(); 117 } 118 bool nmethod::is_compiled_by_shark() const { 119 if (compiler() == NULL) { 120 return false; 121 } 122 return compiler()->is_shark(); 123 } 124 125 126 127 //--------------------------------------------------------------------------------- 128 // NMethod statistics 129 // They are printed under various flags, including: 130 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation. 131 // (In the latter two cases, they like other stats are printed to the log only.) 132 133 #ifndef PRODUCT 134 // These variables are put into one block to reduce relocations 135 // and make it simpler to print from the debugger. 136 struct java_nmethod_stats_struct { 137 int nmethod_count; 138 int total_size; 139 int relocation_size; 140 int consts_size; 141 int insts_size; 142 int stub_size; 143 int scopes_data_size; 144 int scopes_pcs_size; 145 int dependencies_size; 146 int handler_table_size; 147 int nul_chk_table_size; 148 int oops_size; 149 int metadata_size; 150 151 void note_nmethod(nmethod* nm) { 152 nmethod_count += 1; 153 total_size += nm->size(); 154 relocation_size += nm->relocation_size(); 155 consts_size += nm->consts_size(); 156 insts_size += nm->insts_size(); 157 stub_size += nm->stub_size(); 158 oops_size += nm->oops_size(); 159 metadata_size += nm->metadata_size(); 160 scopes_data_size += nm->scopes_data_size(); 161 scopes_pcs_size += nm->scopes_pcs_size(); 162 dependencies_size += nm->dependencies_size(); 163 handler_table_size += nm->handler_table_size(); 164 nul_chk_table_size += nm->nul_chk_table_size(); 165 } 166 void print_nmethod_stats(const char* name) { 167 if (nmethod_count == 0) return; 168 tty->print_cr("Statistics for %d bytecoded nmethods for %s:", nmethod_count, name); 169 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size); 170 if (nmethod_count != 0) tty->print_cr(" header = " SIZE_FORMAT, nmethod_count * sizeof(nmethod)); 171 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size); 172 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size); 173 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size); 174 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size); 175 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size); 176 if (metadata_size != 0) tty->print_cr(" metadata = %d", metadata_size); 177 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size); 178 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size); 179 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size); 180 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size); 181 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size); 182 } 183 }; 184 185 struct native_nmethod_stats_struct { 186 int native_nmethod_count; 187 int native_total_size; 188 int native_relocation_size; 189 int native_insts_size; 190 int native_oops_size; 191 int native_metadata_size; 192 void note_native_nmethod(nmethod* nm) { 193 native_nmethod_count += 1; 194 native_total_size += nm->size(); 195 native_relocation_size += nm->relocation_size(); 196 native_insts_size += nm->insts_size(); 197 native_oops_size += nm->oops_size(); 198 native_metadata_size += nm->metadata_size(); 199 } 200 void print_native_nmethod_stats() { 201 if (native_nmethod_count == 0) return; 202 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count); 203 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size); 204 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size); 205 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size); 206 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size); 207 if (native_metadata_size != 0) tty->print_cr(" N. metadata = %d", native_metadata_size); 208 } 209 }; 210 211 struct pc_nmethod_stats_struct { 212 int pc_desc_resets; // number of resets (= number of caches) 213 int pc_desc_queries; // queries to nmethod::find_pc_desc 214 int pc_desc_approx; // number of those which have approximate true 215 int pc_desc_repeats; // number of _pc_descs[0] hits 216 int pc_desc_hits; // number of LRU cache hits 217 int pc_desc_tests; // total number of PcDesc examinations 218 int pc_desc_searches; // total number of quasi-binary search steps 219 int pc_desc_adds; // number of LUR cache insertions 220 221 void print_pc_stats() { 222 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query", 223 pc_desc_queries, 224 (double)(pc_desc_tests + pc_desc_searches) 225 / pc_desc_queries); 226 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d", 227 pc_desc_resets, 228 pc_desc_queries, pc_desc_approx, 229 pc_desc_repeats, pc_desc_hits, 230 pc_desc_tests, pc_desc_searches, pc_desc_adds); 231 } 232 }; 233 234 #ifdef COMPILER1 235 static java_nmethod_stats_struct c1_java_nmethod_stats; 236 #endif 237 #ifdef COMPILER2 238 static java_nmethod_stats_struct c2_java_nmethod_stats; 239 #endif 240 #if INCLUDE_JVMCI 241 static java_nmethod_stats_struct jvmci_java_nmethod_stats; 242 #endif 243 #ifdef SHARK 244 static java_nmethod_stats_struct shark_java_nmethod_stats; 245 #endif 246 static java_nmethod_stats_struct unknown_java_nmethod_stats; 247 248 static native_nmethod_stats_struct native_nmethod_stats; 249 static pc_nmethod_stats_struct pc_nmethod_stats; 250 251 static void note_java_nmethod(nmethod* nm) { 252 #ifdef COMPILER1 253 if (nm->is_compiled_by_c1()) { 254 c1_java_nmethod_stats.note_nmethod(nm); 255 } else 256 #endif 257 #ifdef COMPILER2 258 if (nm->is_compiled_by_c2()) { 259 c2_java_nmethod_stats.note_nmethod(nm); 260 } else 261 #endif 262 #if INCLUDE_JVMCI 263 if (nm->is_compiled_by_jvmci()) { 264 jvmci_java_nmethod_stats.note_nmethod(nm); 265 } else 266 #endif 267 #ifdef SHARK 268 if (nm->is_compiled_by_shark()) { 269 shark_java_nmethod_stats.note_nmethod(nm); 270 } else 271 #endif 272 { 273 unknown_java_nmethod_stats.note_nmethod(nm); 274 } 275 } 276 #endif // !PRODUCT 277 278 //--------------------------------------------------------------------------------- 279 280 281 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) { 282 assert(pc != NULL, "Must be non null"); 283 assert(exception.not_null(), "Must be non null"); 284 assert(handler != NULL, "Must be non null"); 285 286 _count = 0; 287 _exception_type = exception->klass(); 288 _next = NULL; 289 290 add_address_and_handler(pc,handler); 291 } 292 293 294 address ExceptionCache::match(Handle exception, address pc) { 295 assert(pc != NULL,"Must be non null"); 296 assert(exception.not_null(),"Must be non null"); 297 if (exception->klass() == exception_type()) { 298 return (test_address(pc)); 299 } 300 301 return NULL; 302 } 303 304 305 bool ExceptionCache::match_exception_with_space(Handle exception) { 306 assert(exception.not_null(),"Must be non null"); 307 if (exception->klass() == exception_type() && count() < cache_size) { 308 return true; 309 } 310 return false; 311 } 312 313 314 address ExceptionCache::test_address(address addr) { 315 for (int i=0; i<count(); i++) { 316 if (pc_at(i) == addr) { 317 return handler_at(i); 318 } 319 } 320 return NULL; 321 } 322 323 324 bool ExceptionCache::add_address_and_handler(address addr, address handler) { 325 if (test_address(addr) == handler) return true; 326 327 int index = count(); 328 if (index < cache_size) { 329 set_pc_at(index, addr); 330 set_handler_at(index, handler); 331 OrderAccess::storestore(); 332 increment_count(); 333 return true; 334 } 335 return false; 336 } 337 338 339 // private method for handling exception cache 340 // These methods are private, and used to manipulate the exception cache 341 // directly. 342 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) { 343 ExceptionCache* ec = exception_cache(); 344 while (ec != NULL) { 345 if (ec->match_exception_with_space(exception)) { 346 return ec; 347 } 348 ec = ec->next(); 349 } 350 return NULL; 351 } 352 353 354 //----------------------------------------------------------------------------- 355 356 357 // Helper used by both find_pc_desc methods. 358 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) { 359 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests); 360 if (!approximate) 361 return pc->pc_offset() == pc_offset; 362 else 363 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset(); 364 } 365 366 void PcDescCache::reset_to(PcDesc* initial_pc_desc) { 367 if (initial_pc_desc == NULL) { 368 _pc_descs[0] = NULL; // native method; no PcDescs at all 369 return; 370 } 371 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets); 372 // reset the cache by filling it with benign (non-null) values 373 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel"); 374 for (int i = 0; i < cache_size; i++) 375 _pc_descs[i] = initial_pc_desc; 376 } 377 378 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) { 379 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_queries); 380 NOT_PRODUCT(if (approximate) ++pc_nmethod_stats.pc_desc_approx); 381 382 // Note: one might think that caching the most recently 383 // read value separately would be a win, but one would be 384 // wrong. When many threads are updating it, the cache 385 // line it's in would bounce between caches, negating 386 // any benefit. 387 388 // In order to prevent race conditions do not load cache elements 389 // repeatedly, but use a local copy: 390 PcDesc* res; 391 392 // Step one: Check the most recently added value. 393 res = _pc_descs[0]; 394 if (res == NULL) return NULL; // native method; no PcDescs at all 395 if (match_desc(res, pc_offset, approximate)) { 396 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats); 397 return res; 398 } 399 400 // Step two: Check the rest of the LRU cache. 401 for (int i = 1; i < cache_size; ++i) { 402 res = _pc_descs[i]; 403 if (res->pc_offset() < 0) break; // optimization: skip empty cache 404 if (match_desc(res, pc_offset, approximate)) { 405 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits); 406 return res; 407 } 408 } 409 410 // Report failure. 411 return NULL; 412 } 413 414 void PcDescCache::add_pc_desc(PcDesc* pc_desc) { 415 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds); 416 // Update the LRU cache by shifting pc_desc forward. 417 for (int i = 0; i < cache_size; i++) { 418 PcDesc* next = _pc_descs[i]; 419 _pc_descs[i] = pc_desc; 420 pc_desc = next; 421 } 422 } 423 424 // adjust pcs_size so that it is a multiple of both oopSize and 425 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple 426 // of oopSize, then 2*sizeof(PcDesc) is) 427 static int adjust_pcs_size(int pcs_size) { 428 int nsize = round_to(pcs_size, oopSize); 429 if ((nsize % sizeof(PcDesc)) != 0) { 430 nsize = pcs_size + sizeof(PcDesc); 431 } 432 assert((nsize % oopSize) == 0, "correct alignment"); 433 return nsize; 434 } 435 436 //----------------------------------------------------------------------------- 437 438 439 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) { 440 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock"); 441 assert(new_entry != NULL,"Must be non null"); 442 assert(new_entry->next() == NULL, "Must be null"); 443 444 if (exception_cache() != NULL) { 445 new_entry->set_next(exception_cache()); 446 } 447 set_exception_cache(new_entry); 448 } 449 450 void nmethod::clean_exception_cache(BoolObjectClosure* is_alive) { 451 ExceptionCache* prev = NULL; 452 ExceptionCache* curr = exception_cache(); 453 454 while (curr != NULL) { 455 ExceptionCache* next = curr->next(); 456 457 Klass* ex_klass = curr->exception_type(); 458 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) { 459 if (prev == NULL) { 460 set_exception_cache(next); 461 } else { 462 prev->set_next(next); 463 } 464 delete curr; 465 // prev stays the same. 466 } else { 467 prev = curr; 468 } 469 470 curr = next; 471 } 472 } 473 474 // public method for accessing the exception cache 475 // These are the public access methods. 476 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) { 477 // We never grab a lock to read the exception cache, so we may 478 // have false negatives. This is okay, as it can only happen during 479 // the first few exception lookups for a given nmethod. 480 ExceptionCache* ec = exception_cache(); 481 while (ec != NULL) { 482 address ret_val; 483 if ((ret_val = ec->match(exception,pc)) != NULL) { 484 return ret_val; 485 } 486 ec = ec->next(); 487 } 488 return NULL; 489 } 490 491 492 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) { 493 // There are potential race conditions during exception cache updates, so we 494 // must own the ExceptionCache_lock before doing ANY modifications. Because 495 // we don't lock during reads, it is possible to have several threads attempt 496 // to update the cache with the same data. We need to check for already inserted 497 // copies of the current data before adding it. 498 499 MutexLocker ml(ExceptionCache_lock); 500 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception); 501 502 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) { 503 target_entry = new ExceptionCache(exception,pc,handler); 504 add_exception_cache_entry(target_entry); 505 } 506 } 507 508 509 //-------------end of code for ExceptionCache-------------- 510 511 512 int nmethod::total_size() const { 513 return 514 consts_size() + 515 insts_size() + 516 stub_size() + 517 scopes_data_size() + 518 scopes_pcs_size() + 519 handler_table_size() + 520 nul_chk_table_size(); 521 } 522 523 const char* nmethod::compile_kind() const { 524 if (is_osr_method()) return "osr"; 525 if (method() != NULL && is_native_method()) return "c2n"; 526 return NULL; 527 } 528 529 // Fill in default values for various flag fields 530 void nmethod::init_defaults() { 531 _state = in_use; 532 _unloading_clock = 0; 533 _marked_for_reclamation = 0; 534 _has_flushed_dependencies = 0; 535 _has_unsafe_access = 0; 536 _has_method_handle_invokes = 0; 537 _lazy_critical_native = 0; 538 _has_wide_vectors = 0; 539 _mark_for_deoptimization_status = not_marked; 540 _lock_count = 0; 541 _stack_traversal_mark = 0; 542 _unload_reported = false; // jvmti state 543 544 #ifdef ASSERT 545 _oops_are_stale = false; 546 #endif 547 548 _oops_do_mark_link = NULL; 549 _jmethod_id = NULL; 550 _osr_link = NULL; 551 if (UseG1GC) { 552 _unloading_next = NULL; 553 } else { 554 _scavenge_root_link = NULL; 555 } 556 _scavenge_root_state = 0; 557 _compiler = NULL; 558 #if INCLUDE_RTM_OPT 559 _rtm_state = NoRTM; 560 #endif 561 #if INCLUDE_JVMCI 562 _jvmci_installed_code = NULL; 563 _speculation_log = NULL; 564 #endif 565 } 566 567 nmethod* nmethod::new_native_nmethod(const methodHandle& method, 568 int compile_id, 569 CodeBuffer *code_buffer, 570 int vep_offset, 571 int frame_complete, 572 int frame_size, 573 ByteSize basic_lock_owner_sp_offset, 574 ByteSize basic_lock_sp_offset, 575 OopMapSet* oop_maps) { 576 code_buffer->finalize_oop_references(method); 577 // create nmethod 578 nmethod* nm = NULL; 579 { 580 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 581 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); 582 CodeOffsets offsets; 583 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); 584 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); 585 nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), native_nmethod_size, 586 compile_id, &offsets, 587 code_buffer, frame_size, 588 basic_lock_owner_sp_offset, 589 basic_lock_sp_offset, oop_maps); 590 NOT_PRODUCT(if (nm != NULL) native_nmethod_stats.note_native_nmethod(nm)); 591 } 592 // verify nmethod 593 debug_only(if (nm) nm->verify();) // might block 594 595 if (nm != NULL) { 596 nm->log_new_nmethod(); 597 } 598 599 return nm; 600 } 601 602 nmethod* nmethod::new_nmethod(const methodHandle& method, 603 int compile_id, 604 int entry_bci, 605 CodeOffsets* offsets, 606 int orig_pc_offset, 607 DebugInformationRecorder* debug_info, 608 Dependencies* dependencies, 609 CodeBuffer* code_buffer, int frame_size, 610 OopMapSet* oop_maps, 611 ExceptionHandlerTable* handler_table, 612 ImplicitExceptionTable* nul_chk_table, 613 AbstractCompiler* compiler, 614 int comp_level 615 #if INCLUDE_JVMCI 616 , Handle installed_code, 617 Handle speculationLog 618 #endif 619 ) 620 { 621 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 622 code_buffer->finalize_oop_references(method); 623 // create nmethod 624 nmethod* nm = NULL; 625 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 626 int nmethod_size = 627 allocation_size(code_buffer, sizeof(nmethod)) 628 + adjust_pcs_size(debug_info->pcs_size()) 629 + round_to(dependencies->size_in_bytes() , oopSize) 630 + round_to(handler_table->size_in_bytes(), oopSize) 631 + round_to(nul_chk_table->size_in_bytes(), oopSize) 632 + round_to(debug_info->data_size() , oopSize); 633 634 nm = new (nmethod_size, comp_level) 635 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, 636 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, 637 oop_maps, 638 handler_table, 639 nul_chk_table, 640 compiler, 641 comp_level 642 #if INCLUDE_JVMCI 643 , installed_code, 644 speculationLog 645 #endif 646 ); 647 648 if (nm != NULL) { 649 // To make dependency checking during class loading fast, record 650 // the nmethod dependencies in the classes it is dependent on. 651 // This allows the dependency checking code to simply walk the 652 // class hierarchy above the loaded class, checking only nmethods 653 // which are dependent on those classes. The slow way is to 654 // check every nmethod for dependencies which makes it linear in 655 // the number of methods compiled. For applications with a lot 656 // classes the slow way is too slow. 657 for (Dependencies::DepStream deps(nm); deps.next(); ) { 658 if (deps.type() == Dependencies::call_site_target_value) { 659 // CallSite dependencies are managed on per-CallSite instance basis. 660 oop call_site = deps.argument_oop(0); 661 MethodHandles::add_dependent_nmethod(call_site, nm); 662 } else { 663 Klass* klass = deps.context_type(); 664 if (klass == NULL) { 665 continue; // ignore things like evol_method 666 } 667 // record this nmethod as dependent on this klass 668 InstanceKlass::cast(klass)->add_dependent_nmethod(nm); 669 } 670 } 671 NOT_PRODUCT(if (nm != NULL) note_java_nmethod(nm)); 672 } 673 } 674 // Do verification and logging outside CodeCache_lock. 675 if (nm != NULL) { 676 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet. 677 DEBUG_ONLY(nm->verify();) 678 nm->log_new_nmethod(); 679 } 680 return nm; 681 } 682 683 // For native wrappers 684 nmethod::nmethod( 685 Method* method, 686 int nmethod_size, 687 int compile_id, 688 CodeOffsets* offsets, 689 CodeBuffer* code_buffer, 690 int frame_size, 691 ByteSize basic_lock_owner_sp_offset, 692 ByteSize basic_lock_sp_offset, 693 OopMapSet* oop_maps ) 694 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod), 695 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 696 _native_receiver_sp_offset(basic_lock_owner_sp_offset), 697 _native_basic_lock_sp_offset(basic_lock_sp_offset) 698 { 699 { 700 debug_only(NoSafepointVerifier nsv;) 701 assert_locked_or_safepoint(CodeCache_lock); 702 703 init_defaults(); 704 _method = method; 705 _entry_bci = InvocationEntryBci; 706 // We have no exception handler or deopt handler make the 707 // values something that will never match a pc like the nmethod vtable entry 708 _exception_offset = 0; 709 _deoptimize_offset = 0; 710 _deoptimize_mh_offset = 0; 711 _orig_pc_offset = 0; 712 713 _consts_offset = data_offset(); 714 _stub_offset = data_offset(); 715 _oops_offset = data_offset(); 716 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 717 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 718 _scopes_pcs_offset = _scopes_data_offset; 719 _dependencies_offset = _scopes_pcs_offset; 720 _handler_table_offset = _dependencies_offset; 721 _nul_chk_table_offset = _handler_table_offset; 722 _nmethod_end_offset = _nul_chk_table_offset; 723 _compile_id = compile_id; 724 _comp_level = CompLevel_none; 725 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 726 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 727 _osr_entry_point = NULL; 728 _exception_cache = NULL; 729 _pc_desc_cache.reset_to(NULL); 730 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 731 732 code_buffer->copy_values_to(this); 733 if (ScavengeRootsInCode) { 734 if (detect_scavenge_root_oops()) { 735 CodeCache::add_scavenge_root_nmethod(this); 736 } 737 Universe::heap()->register_nmethod(this); 738 } 739 debug_only(verify_scavenge_root_oops()); 740 CodeCache::commit(this); 741 } 742 743 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) { 744 ttyLocker ttyl; // keep the following output all in one block 745 // This output goes directly to the tty, not the compiler log. 746 // To enable tools to match it up with the compilation activity, 747 // be sure to tag this tty output with the compile ID. 748 if (xtty != NULL) { 749 xtty->begin_head("print_native_nmethod"); 750 xtty->method(_method); 751 xtty->stamp(); 752 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this); 753 } 754 // print the header part first 755 print(); 756 // then print the requested information 757 if (PrintNativeNMethods) { 758 print_code(); 759 if (oop_maps != NULL) { 760 oop_maps->print(); 761 } 762 } 763 if (PrintRelocations) { 764 print_relocations(); 765 } 766 if (xtty != NULL) { 767 xtty->tail("print_native_nmethod"); 768 } 769 } 770 } 771 772 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () { 773 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level)); 774 } 775 776 nmethod::nmethod( 777 Method* method, 778 int nmethod_size, 779 int compile_id, 780 int entry_bci, 781 CodeOffsets* offsets, 782 int orig_pc_offset, 783 DebugInformationRecorder* debug_info, 784 Dependencies* dependencies, 785 CodeBuffer *code_buffer, 786 int frame_size, 787 OopMapSet* oop_maps, 788 ExceptionHandlerTable* handler_table, 789 ImplicitExceptionTable* nul_chk_table, 790 AbstractCompiler* compiler, 791 int comp_level 792 #if INCLUDE_JVMCI 793 , Handle installed_code, 794 Handle speculation_log 795 #endif 796 ) 797 : CodeBlob("nmethod", code_buffer, sizeof(nmethod), 798 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps), 799 _native_receiver_sp_offset(in_ByteSize(-1)), 800 _native_basic_lock_sp_offset(in_ByteSize(-1)) 801 { 802 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR"); 803 { 804 debug_only(NoSafepointVerifier nsv;) 805 assert_locked_or_safepoint(CodeCache_lock); 806 807 init_defaults(); 808 _method = method; 809 _entry_bci = entry_bci; 810 _compile_id = compile_id; 811 _comp_level = comp_level; 812 _compiler = compiler; 813 _orig_pc_offset = orig_pc_offset; 814 _hotness_counter = NMethodSweeper::hotness_counter_reset_val(); 815 816 // Section offsets 817 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts()); 818 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs()); 819 820 #if INCLUDE_JVMCI 821 _jvmci_installed_code = installed_code(); 822 _speculation_log = (instanceOop)speculation_log(); 823 824 if (compiler->is_jvmci()) { 825 // JVMCI might not produce any stub sections 826 if (offsets->value(CodeOffsets::Exceptions) != -1) { 827 _exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions); 828 } else { 829 _exception_offset = -1; 830 } 831 if (offsets->value(CodeOffsets::Deopt) != -1) { 832 _deoptimize_offset = code_offset() + offsets->value(CodeOffsets::Deopt); 833 } else { 834 _deoptimize_offset = -1; 835 } 836 if (offsets->value(CodeOffsets::DeoptMH) != -1) { 837 _deoptimize_mh_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH); 838 } else { 839 _deoptimize_mh_offset = -1; 840 } 841 } else { 842 #endif 843 // Exception handler and deopt handler are in the stub section 844 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set"); 845 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set"); 846 847 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions); 848 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt); 849 if (offsets->value(CodeOffsets::DeoptMH) != -1) { 850 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH); 851 } else { 852 _deoptimize_mh_offset = -1; 853 #if INCLUDE_JVMCI 854 } 855 #endif 856 } 857 if (offsets->value(CodeOffsets::UnwindHandler) != -1) { 858 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler); 859 } else { 860 _unwind_handler_offset = -1; 861 } 862 863 _oops_offset = data_offset(); 864 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize); 865 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize); 866 867 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize); 868 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size()); 869 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize); 870 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize); 871 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize); 872 873 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry); 874 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry); 875 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry); 876 _exception_cache = NULL; 877 _pc_desc_cache.reset_to(scopes_pcs_begin()); 878 879 // Copy contents of ScopeDescRecorder to nmethod 880 code_buffer->copy_values_to(this); 881 debug_info->copy_to(this); 882 dependencies->copy_to(this); 883 if (ScavengeRootsInCode) { 884 if (detect_scavenge_root_oops()) { 885 CodeCache::add_scavenge_root_nmethod(this); 886 } 887 Universe::heap()->register_nmethod(this); 888 } 889 debug_only(verify_scavenge_root_oops()); 890 891 CodeCache::commit(this); 892 893 // Copy contents of ExceptionHandlerTable to nmethod 894 handler_table->copy_to(this); 895 nul_chk_table->copy_to(this); 896 897 // we use the information of entry points to find out if a method is 898 // static or non static 899 assert(compiler->is_c2() || compiler->is_jvmci() || 900 _method->is_static() == (entry_point() == _verified_entry_point), 901 " entry points must be same for static methods and vice versa"); 902 } 903 } 904 905 // Print a short set of xml attributes to identify this nmethod. The 906 // output should be embedded in some other element. 907 void nmethod::log_identity(xmlStream* log) const { 908 log->print(" compile_id='%d'", compile_id()); 909 const char* nm_kind = compile_kind(); 910 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind); 911 if (compiler() != NULL) { 912 log->print(" compiler='%s'", compiler()->name()); 913 } 914 if (TieredCompilation) { 915 log->print(" level='%d'", comp_level()); 916 } 917 } 918 919 920 #define LOG_OFFSET(log, name) \ 921 if (p2i(name##_end()) - p2i(name##_begin())) \ 922 log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'" , \ 923 p2i(name##_begin()) - p2i(this)) 924 925 926 void nmethod::log_new_nmethod() const { 927 if (LogCompilation && xtty != NULL) { 928 ttyLocker ttyl; 929 HandleMark hm; 930 xtty->begin_elem("nmethod"); 931 log_identity(xtty); 932 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size()); 933 xtty->print(" address='" INTPTR_FORMAT "'", p2i(this)); 934 935 LOG_OFFSET(xtty, relocation); 936 LOG_OFFSET(xtty, consts); 937 LOG_OFFSET(xtty, insts); 938 LOG_OFFSET(xtty, stub); 939 LOG_OFFSET(xtty, scopes_data); 940 LOG_OFFSET(xtty, scopes_pcs); 941 LOG_OFFSET(xtty, dependencies); 942 LOG_OFFSET(xtty, handler_table); 943 LOG_OFFSET(xtty, nul_chk_table); 944 LOG_OFFSET(xtty, oops); 945 LOG_OFFSET(xtty, metadata); 946 947 xtty->method(method()); 948 xtty->stamp(); 949 xtty->end_elem(); 950 } 951 } 952 953 #undef LOG_OFFSET 954 955 956 // Print out more verbose output usually for a newly created nmethod. 957 void nmethod::print_on(outputStream* st, const char* msg) const { 958 if (st != NULL) { 959 ttyLocker ttyl; 960 if (WizardMode) { 961 CompileTask::print(st, this, msg, /*short_form:*/ true); 962 st->print_cr(" (" INTPTR_FORMAT ")", p2i(this)); 963 } else { 964 CompileTask::print(st, this, msg, /*short_form:*/ false); 965 } 966 } 967 } 968 969 void nmethod::maybe_print_nmethod(DirectiveSet* directive) { 970 bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption; 971 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) { 972 print_nmethod(printnmethods); 973 } 974 } 975 976 void nmethod::print_nmethod(bool printmethod) { 977 ttyLocker ttyl; // keep the following output all in one block 978 if (xtty != NULL) { 979 xtty->begin_head("print_nmethod"); 980 xtty->stamp(); 981 xtty->end_head(); 982 } 983 // print the header part first 984 print(); 985 // then print the requested information 986 if (printmethod) { 987 print_code(); 988 print_pcs(); 989 if (oop_maps()) { 990 oop_maps()->print(); 991 } 992 } 993 if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) { 994 print_scopes(); 995 } 996 if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) { 997 print_relocations(); 998 } 999 if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) { 1000 print_dependencies(); 1001 } 1002 if (printmethod || PrintExceptionHandlers) { 1003 print_handler_table(); 1004 print_nul_chk_table(); 1005 } 1006 if (printmethod) { 1007 print_recorded_oops(); 1008 print_recorded_metadata(); 1009 } 1010 if (xtty != NULL) { 1011 xtty->tail("print_nmethod"); 1012 } 1013 } 1014 1015 1016 // Promote one word from an assembly-time handle to a live embedded oop. 1017 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) { 1018 if (handle == NULL || 1019 // As a special case, IC oops are initialized to 1 or -1. 1020 handle == (jobject) Universe::non_oop_word()) { 1021 (*dest) = (oop) handle; 1022 } else { 1023 (*dest) = JNIHandles::resolve_non_null(handle); 1024 } 1025 } 1026 1027 1028 // Have to have the same name because it's called by a template 1029 void nmethod::copy_values(GrowableArray<jobject>* array) { 1030 int length = array->length(); 1031 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough"); 1032 oop* dest = oops_begin(); 1033 for (int index = 0 ; index < length; index++) { 1034 initialize_immediate_oop(&dest[index], array->at(index)); 1035 } 1036 1037 // Now we can fix up all the oops in the code. We need to do this 1038 // in the code because the assembler uses jobjects as placeholders. 1039 // The code and relocations have already been initialized by the 1040 // CodeBlob constructor, so it is valid even at this early point to 1041 // iterate over relocations and patch the code. 1042 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true); 1043 } 1044 1045 void nmethod::copy_values(GrowableArray<Metadata*>* array) { 1046 int length = array->length(); 1047 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough"); 1048 Metadata** dest = metadata_begin(); 1049 for (int index = 0 ; index < length; index++) { 1050 dest[index] = array->at(index); 1051 } 1052 } 1053 1054 bool nmethod::is_at_poll_return(address pc) { 1055 RelocIterator iter(this, pc, pc+1); 1056 while (iter.next()) { 1057 if (iter.type() == relocInfo::poll_return_type) 1058 return true; 1059 } 1060 return false; 1061 } 1062 1063 1064 bool nmethod::is_at_poll_or_poll_return(address pc) { 1065 RelocIterator iter(this, pc, pc+1); 1066 while (iter.next()) { 1067 relocInfo::relocType t = iter.type(); 1068 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type) 1069 return true; 1070 } 1071 return false; 1072 } 1073 1074 1075 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) { 1076 // re-patch all oop-bearing instructions, just in case some oops moved 1077 RelocIterator iter(this, begin, end); 1078 while (iter.next()) { 1079 if (iter.type() == relocInfo::oop_type) { 1080 oop_Relocation* reloc = iter.oop_reloc(); 1081 if (initialize_immediates && reloc->oop_is_immediate()) { 1082 oop* dest = reloc->oop_addr(); 1083 initialize_immediate_oop(dest, (jobject) *dest); 1084 } 1085 // Refresh the oop-related bits of this instruction. 1086 reloc->fix_oop_relocation(); 1087 } else if (iter.type() == relocInfo::metadata_type) { 1088 metadata_Relocation* reloc = iter.metadata_reloc(); 1089 reloc->fix_metadata_relocation(); 1090 } 1091 } 1092 } 1093 1094 1095 void nmethod::verify_oop_relocations() { 1096 // Ensure sure that the code matches the current oop values 1097 RelocIterator iter(this, NULL, NULL); 1098 while (iter.next()) { 1099 if (iter.type() == relocInfo::oop_type) { 1100 oop_Relocation* reloc = iter.oop_reloc(); 1101 if (!reloc->oop_is_immediate()) { 1102 reloc->verify_oop_relocation(); 1103 } 1104 } 1105 } 1106 } 1107 1108 1109 ScopeDesc* nmethod::scope_desc_at(address pc) { 1110 PcDesc* pd = pc_desc_at(pc); 1111 guarantee(pd != NULL, "scope must be present"); 1112 return new ScopeDesc(this, pd->scope_decode_offset(), 1113 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(), 1114 pd->return_oop()); 1115 } 1116 1117 1118 void nmethod::clear_inline_caches() { 1119 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint"); 1120 if (is_zombie()) { 1121 return; 1122 } 1123 1124 RelocIterator iter(this); 1125 while (iter.next()) { 1126 iter.reloc()->clear_inline_cache(); 1127 } 1128 } 1129 1130 // Clear ICStubs of all compiled ICs 1131 void nmethod::clear_ic_stubs() { 1132 assert_locked_or_safepoint(CompiledIC_lock); 1133 RelocIterator iter(this); 1134 while(iter.next()) { 1135 if (iter.type() == relocInfo::virtual_call_type) { 1136 CompiledIC* ic = CompiledIC_at(&iter); 1137 ic->clear_ic_stub(); 1138 } 1139 } 1140 } 1141 1142 1143 void nmethod::cleanup_inline_caches() { 1144 assert_locked_or_safepoint(CompiledIC_lock); 1145 1146 // If the method is not entrant or zombie then a JMP is plastered over the 1147 // first few bytes. If an oop in the old code was there, that oop 1148 // should not get GC'd. Skip the first few bytes of oops on 1149 // not-entrant methods. 1150 address low_boundary = verified_entry_point(); 1151 if (!is_in_use()) { 1152 low_boundary += NativeJump::instruction_size; 1153 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1154 // This means that the low_boundary is going to be a little too high. 1155 // This shouldn't matter, since oops of non-entrant methods are never used. 1156 // In fact, why are we bothering to look at oops in a non-entrant method?? 1157 } 1158 1159 // Find all calls in an nmethod and clear the ones that point to non-entrant, 1160 // zombie and unloaded nmethods. 1161 ResourceMark rm; 1162 RelocIterator iter(this, low_boundary); 1163 while(iter.next()) { 1164 switch(iter.type()) { 1165 case relocInfo::virtual_call_type: 1166 case relocInfo::opt_virtual_call_type: { 1167 CompiledIC *ic = CompiledIC_at(&iter); 1168 // Ok, to lookup references to zombies here 1169 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1170 if( cb != NULL && cb->is_nmethod() ) { 1171 nmethod* nm = (nmethod*)cb; 1172 // Clean inline caches pointing to zombie, non-entrant and unloaded methods 1173 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(is_alive()); 1174 } 1175 break; 1176 } 1177 case relocInfo::static_call_type: { 1178 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1179 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1180 if( cb != NULL && cb->is_nmethod() ) { 1181 nmethod* nm = (nmethod*)cb; 1182 // Clean inline caches pointing to zombie, non-entrant and unloaded methods 1183 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean(); 1184 } 1185 break; 1186 } 1187 } 1188 } 1189 } 1190 1191 void nmethod::verify_clean_inline_caches() { 1192 assert_locked_or_safepoint(CompiledIC_lock); 1193 1194 // If the method is not entrant or zombie then a JMP is plastered over the 1195 // first few bytes. If an oop in the old code was there, that oop 1196 // should not get GC'd. Skip the first few bytes of oops on 1197 // not-entrant methods. 1198 address low_boundary = verified_entry_point(); 1199 if (!is_in_use()) { 1200 low_boundary += NativeJump::instruction_size; 1201 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1202 // This means that the low_boundary is going to be a little too high. 1203 // This shouldn't matter, since oops of non-entrant methods are never used. 1204 // In fact, why are we bothering to look at oops in a non-entrant method?? 1205 } 1206 1207 ResourceMark rm; 1208 RelocIterator iter(this, low_boundary); 1209 while(iter.next()) { 1210 switch(iter.type()) { 1211 case relocInfo::virtual_call_type: 1212 case relocInfo::opt_virtual_call_type: { 1213 CompiledIC *ic = CompiledIC_at(&iter); 1214 // Ok, to lookup references to zombies here 1215 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination()); 1216 if( cb != NULL && cb->is_nmethod() ) { 1217 nmethod* nm = (nmethod*)cb; 1218 // Verify that inline caches pointing to both zombie and not_entrant methods are clean 1219 if (!nm->is_in_use() || (nm->method()->code() != nm)) { 1220 assert(ic->is_clean(), "IC should be clean"); 1221 } 1222 } 1223 break; 1224 } 1225 case relocInfo::static_call_type: { 1226 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc()); 1227 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination()); 1228 if( cb != NULL && cb->is_nmethod() ) { 1229 nmethod* nm = (nmethod*)cb; 1230 // Verify that inline caches pointing to both zombie and not_entrant methods are clean 1231 if (!nm->is_in_use() || (nm->method()->code() != nm)) { 1232 assert(csc->is_clean(), "IC should be clean"); 1233 } 1234 } 1235 break; 1236 } 1237 } 1238 } 1239 } 1240 1241 int nmethod::verify_icholder_relocations() { 1242 int count = 0; 1243 1244 RelocIterator iter(this); 1245 while(iter.next()) { 1246 if (iter.type() == relocInfo::virtual_call_type) { 1247 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) { 1248 CompiledIC *ic = CompiledIC_at(&iter); 1249 if (TraceCompiledIC) { 1250 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder())); 1251 ic->print(); 1252 } 1253 assert(ic->cached_icholder() != NULL, "must be non-NULL"); 1254 count++; 1255 } 1256 } 1257 } 1258 1259 return count; 1260 } 1261 1262 // This is a private interface with the sweeper. 1263 void nmethod::mark_as_seen_on_stack() { 1264 assert(is_alive(), "Must be an alive method"); 1265 // Set the traversal mark to ensure that the sweeper does 2 1266 // cleaning passes before moving to zombie. 1267 set_stack_traversal_mark(NMethodSweeper::traversal_count()); 1268 } 1269 1270 // Tell if a non-entrant method can be converted to a zombie (i.e., 1271 // there are no activations on the stack, not in use by the VM, 1272 // and not in use by the ServiceThread) 1273 bool nmethod::can_convert_to_zombie() { 1274 assert(is_not_entrant(), "must be a non-entrant method"); 1275 1276 // Since the nmethod sweeper only does partial sweep the sweeper's traversal 1277 // count can be greater than the stack traversal count before it hits the 1278 // nmethod for the second time. 1279 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() && 1280 !is_locked_by_vm(); 1281 } 1282 1283 void nmethod::inc_decompile_count() { 1284 if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return; 1285 // Could be gated by ProfileTraps, but do not bother... 1286 Method* m = method(); 1287 if (m == NULL) return; 1288 MethodData* mdo = m->method_data(); 1289 if (mdo == NULL) return; 1290 // There is a benign race here. See comments in methodData.hpp. 1291 mdo->inc_decompile_count(); 1292 } 1293 1294 void nmethod::increase_unloading_clock() { 1295 _global_unloading_clock++; 1296 if (_global_unloading_clock == 0) { 1297 // _nmethods are allocated with _unloading_clock == 0, 1298 // so 0 is never used as a clock value. 1299 _global_unloading_clock = 1; 1300 } 1301 } 1302 1303 void nmethod::set_unloading_clock(unsigned char unloading_clock) { 1304 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock); 1305 } 1306 1307 unsigned char nmethod::unloading_clock() { 1308 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock); 1309 } 1310 1311 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) { 1312 1313 post_compiled_method_unload(); 1314 1315 // Since this nmethod is being unloaded, make sure that dependencies 1316 // recorded in instanceKlasses get flushed and pass non-NULL closure to 1317 // indicate that this work is being done during a GC. 1318 assert(Universe::heap()->is_gc_active(), "should only be called during gc"); 1319 assert(is_alive != NULL, "Should be non-NULL"); 1320 // A non-NULL is_alive closure indicates that this is being called during GC. 1321 flush_dependencies(is_alive); 1322 1323 // Break cycle between nmethod & method 1324 if (log_is_enabled(Trace, classunload)) { 1325 outputStream* log = LogHandle(classunload)::trace_stream(); 1326 log->print_cr("making nmethod " INTPTR_FORMAT 1327 " unloadable, Method*(" INTPTR_FORMAT 1328 "), cause(" INTPTR_FORMAT ")", 1329 p2i(this), p2i(_method), p2i(cause)); 1330 if (!Universe::heap()->is_gc_active()) 1331 cause->klass()->print_on(log); 1332 } 1333 // Unlink the osr method, so we do not look this up again 1334 if (is_osr_method()) { 1335 invalidate_osr_method(); 1336 } 1337 // If _method is already NULL the Method* is about to be unloaded, 1338 // so we don't have to break the cycle. Note that it is possible to 1339 // have the Method* live here, in case we unload the nmethod because 1340 // it is pointing to some oop (other than the Method*) being unloaded. 1341 if (_method != NULL) { 1342 // OSR methods point to the Method*, but the Method* does not 1343 // point back! 1344 if (_method->code() == this) { 1345 _method->clear_code(); // Break a cycle 1346 } 1347 _method = NULL; // Clear the method of this dead nmethod 1348 } 1349 1350 // Make the class unloaded - i.e., change state and notify sweeper 1351 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1352 if (is_in_use()) { 1353 // Transitioning directly from live to unloaded -- so 1354 // we need to force a cache clean-up; remember this 1355 // for later on. 1356 CodeCache::set_needs_cache_clean(true); 1357 } 1358 1359 // Unregister must be done before the state change 1360 Universe::heap()->unregister_nmethod(this); 1361 1362 _state = unloaded; 1363 1364 // Log the unloading. 1365 log_state_change(); 1366 1367 #if INCLUDE_JVMCI 1368 // The method can only be unloaded after the pointer to the installed code 1369 // Java wrapper is no longer alive. Here we need to clear out this weak 1370 // reference to the dead object. Nulling out the reference has to happen 1371 // after the method is unregistered since the original value may be still 1372 // tracked by the rset. 1373 maybe_invalidate_installed_code(); 1374 // Clear these out after the nmethod has been unregistered and any 1375 // updates to the InstalledCode instance have been performed. 1376 _jvmci_installed_code = NULL; 1377 _speculation_log = NULL; 1378 #endif 1379 1380 // The Method* is gone at this point 1381 assert(_method == NULL, "Tautology"); 1382 1383 set_osr_link(NULL); 1384 NMethodSweeper::report_state_change(this); 1385 } 1386 1387 void nmethod::invalidate_osr_method() { 1388 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); 1389 // Remove from list of active nmethods 1390 if (method() != NULL) 1391 method()->method_holder()->remove_osr_nmethod(this); 1392 } 1393 1394 void nmethod::log_state_change() const { 1395 if (LogCompilation) { 1396 if (xtty != NULL) { 1397 ttyLocker ttyl; // keep the following output all in one block 1398 if (_state == unloaded) { 1399 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'", 1400 os::current_thread_id()); 1401 } else { 1402 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s", 1403 os::current_thread_id(), 1404 (_state == zombie ? " zombie='1'" : "")); 1405 } 1406 log_identity(xtty); 1407 xtty->stamp(); 1408 xtty->end_elem(); 1409 } 1410 } 1411 if (PrintCompilation && _state != unloaded) { 1412 print_on(tty, _state == zombie ? "made zombie" : "made not entrant"); 1413 } 1414 } 1415 1416 /** 1417 * Common functionality for both make_not_entrant and make_zombie 1418 */ 1419 bool nmethod::make_not_entrant_or_zombie(unsigned int state) { 1420 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant"); 1421 assert(!is_zombie(), "should not already be a zombie"); 1422 1423 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below. 1424 nmethodLocker nml(this); 1425 methodHandle the_method(method()); 1426 NoSafepointVerifier nsv; 1427 1428 // during patching, depending on the nmethod state we must notify the GC that 1429 // code has been unloaded, unregistering it. We cannot do this right while 1430 // holding the Patching_lock because we need to use the CodeCache_lock. This 1431 // would be prone to deadlocks. 1432 // This flag is used to remember whether we need to later lock and unregister. 1433 bool nmethod_needs_unregister = false; 1434 1435 { 1436 // invalidate osr nmethod before acquiring the patching lock since 1437 // they both acquire leaf locks and we don't want a deadlock. 1438 // This logic is equivalent to the logic below for patching the 1439 // verified entry point of regular methods. 1440 if (is_osr_method()) { 1441 // this effectively makes the osr nmethod not entrant 1442 invalidate_osr_method(); 1443 } 1444 1445 // Enter critical section. Does not block for safepoint. 1446 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1447 1448 if (_state == state) { 1449 // another thread already performed this transition so nothing 1450 // to do, but return false to indicate this. 1451 return false; 1452 } 1453 1454 // The caller can be calling the method statically or through an inline 1455 // cache call. 1456 if (!is_osr_method() && !is_not_entrant()) { 1457 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(), 1458 SharedRuntime::get_handle_wrong_method_stub()); 1459 } 1460 1461 if (is_in_use() && update_recompile_counts()) { 1462 // It's a true state change, so mark the method as decompiled. 1463 // Do it only for transition from alive. 1464 inc_decompile_count(); 1465 } 1466 1467 // If the state is becoming a zombie, signal to unregister the nmethod with 1468 // the heap. 1469 // This nmethod may have already been unloaded during a full GC. 1470 if ((state == zombie) && !is_unloaded()) { 1471 nmethod_needs_unregister = true; 1472 } 1473 1474 // Must happen before state change. Otherwise we have a race condition in 1475 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately 1476 // transition its state from 'not_entrant' to 'zombie' without having to wait 1477 // for stack scanning. 1478 if (state == not_entrant) { 1479 mark_as_seen_on_stack(); 1480 OrderAccess::storestore(); 1481 } 1482 1483 // Change state 1484 _state = state; 1485 1486 // Log the transition once 1487 log_state_change(); 1488 1489 // Invalidate while holding the patching lock 1490 JVMCI_ONLY(maybe_invalidate_installed_code()); 1491 1492 // Remove nmethod from method. 1493 // We need to check if both the _code and _from_compiled_code_entry_point 1494 // refer to this nmethod because there is a race in setting these two fields 1495 // in Method* as seen in bugid 4947125. 1496 // If the vep() points to the zombie nmethod, the memory for the nmethod 1497 // could be flushed and the compiler and vtable stubs could still call 1498 // through it. 1499 if (method() != NULL && (method()->code() == this || 1500 method()->from_compiled_entry() == verified_entry_point())) { 1501 HandleMark hm; 1502 method()->clear_code(); 1503 } 1504 } // leave critical region under Patching_lock 1505 1506 // When the nmethod becomes zombie it is no longer alive so the 1507 // dependencies must be flushed. nmethods in the not_entrant 1508 // state will be flushed later when the transition to zombie 1509 // happens or they get unloaded. 1510 if (state == zombie) { 1511 { 1512 // Flushing dependecies must be done before any possible 1513 // safepoint can sneak in, otherwise the oops used by the 1514 // dependency logic could have become stale. 1515 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1516 if (nmethod_needs_unregister) { 1517 Universe::heap()->unregister_nmethod(this); 1518 #ifdef JVMCI 1519 _jvmci_installed_code = NULL; 1520 _speculation_log = NULL; 1521 #endif 1522 } 1523 flush_dependencies(NULL); 1524 } 1525 1526 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload 1527 // event and it hasn't already been reported for this nmethod then 1528 // report it now. The event may have been reported earilier if the GC 1529 // marked it for unloading). JvmtiDeferredEventQueue support means 1530 // we no longer go to a safepoint here. 1531 post_compiled_method_unload(); 1532 1533 #ifdef ASSERT 1534 // It's no longer safe to access the oops section since zombie 1535 // nmethods aren't scanned for GC. 1536 _oops_are_stale = true; 1537 #endif 1538 // the Method may be reclaimed by class unloading now that the 1539 // nmethod is in zombie state 1540 set_method(NULL); 1541 } else { 1542 assert(state == not_entrant, "other cases may need to be handled differently"); 1543 } 1544 1545 if (TraceCreateZombies) { 1546 ResourceMark m; 1547 tty->print_cr("nmethod <" INTPTR_FORMAT "> %s code made %s", p2i(this), this->method() ? this->method()->name_and_sig_as_C_string() : "null", (state == not_entrant) ? "not entrant" : "zombie"); 1548 } 1549 1550 NMethodSweeper::report_state_change(this); 1551 return true; 1552 } 1553 1554 void nmethod::flush() { 1555 // Note that there are no valid oops in the nmethod anymore. 1556 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method"); 1557 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation"); 1558 1559 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed"); 1560 assert_locked_or_safepoint(CodeCache_lock); 1561 1562 // completely deallocate this method 1563 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this)); 1564 if (PrintMethodFlushing) { 1565 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT 1566 "/Free CodeCache:" SIZE_FORMAT "Kb", 1567 _compile_id, p2i(this), CodeCache::blob_count(), 1568 CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024); 1569 } 1570 1571 // We need to deallocate any ExceptionCache data. 1572 // Note that we do not need to grab the nmethod lock for this, it 1573 // better be thread safe if we're disposing of it! 1574 ExceptionCache* ec = exception_cache(); 1575 set_exception_cache(NULL); 1576 while(ec != NULL) { 1577 ExceptionCache* next = ec->next(); 1578 delete ec; 1579 ec = next; 1580 } 1581 1582 if (on_scavenge_root_list()) { 1583 CodeCache::drop_scavenge_root_nmethod(this); 1584 } 1585 1586 #ifdef SHARK 1587 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin()); 1588 #endif // SHARK 1589 1590 ((CodeBlob*)(this))->flush(); 1591 1592 CodeCache::free(this); 1593 } 1594 1595 // 1596 // Notify all classes this nmethod is dependent on that it is no 1597 // longer dependent. This should only be called in two situations. 1598 // First, when a nmethod transitions to a zombie all dependents need 1599 // to be clear. Since zombification happens at a safepoint there's no 1600 // synchronization issues. The second place is a little more tricky. 1601 // During phase 1 of mark sweep class unloading may happen and as a 1602 // result some nmethods may get unloaded. In this case the flushing 1603 // of dependencies must happen during phase 1 since after GC any 1604 // dependencies in the unloaded nmethod won't be updated, so 1605 // traversing the dependency information in unsafe. In that case this 1606 // function is called with a non-NULL argument and this function only 1607 // notifies instanceKlasses that are reachable 1608 1609 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) { 1610 assert_locked_or_safepoint(CodeCache_lock); 1611 assert(Universe::heap()->is_gc_active() == (is_alive != NULL), 1612 "is_alive is non-NULL if and only if we are called during GC"); 1613 if (!has_flushed_dependencies()) { 1614 set_has_flushed_dependencies(); 1615 for (Dependencies::DepStream deps(this); deps.next(); ) { 1616 if (deps.type() == Dependencies::call_site_target_value) { 1617 // CallSite dependencies are managed on per-CallSite instance basis. 1618 oop call_site = deps.argument_oop(0); 1619 MethodHandles::remove_dependent_nmethod(call_site, this); 1620 } else { 1621 Klass* klass = deps.context_type(); 1622 if (klass == NULL) { 1623 continue; // ignore things like evol_method 1624 } 1625 // During GC the is_alive closure is non-NULL, and is used to 1626 // determine liveness of dependees that need to be updated. 1627 if (is_alive == NULL || klass->is_loader_alive(is_alive)) { 1628 // The GC defers deletion of this entry, since there might be multiple threads 1629 // iterating over the _dependencies graph. Other call paths are single-threaded 1630 // and may delete it immediately. 1631 bool delete_immediately = is_alive == NULL; 1632 InstanceKlass::cast(klass)->remove_dependent_nmethod(this, delete_immediately); 1633 } 1634 } 1635 } 1636 } 1637 } 1638 1639 1640 // If this oop is not live, the nmethod can be unloaded. 1641 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) { 1642 assert(root != NULL, "just checking"); 1643 oop obj = *root; 1644 if (obj == NULL || is_alive->do_object_b(obj)) { 1645 return false; 1646 } 1647 1648 // If ScavengeRootsInCode is true, an nmethod might be unloaded 1649 // simply because one of its constant oops has gone dead. 1650 // No actual classes need to be unloaded in order for this to occur. 1651 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading"); 1652 make_unloaded(is_alive, obj); 1653 return true; 1654 } 1655 1656 // ------------------------------------------------------------------ 1657 // post_compiled_method_load_event 1658 // new method for install_code() path 1659 // Transfer information from compilation to jvmti 1660 void nmethod::post_compiled_method_load_event() { 1661 1662 Method* moop = method(); 1663 HOTSPOT_COMPILED_METHOD_LOAD( 1664 (char *) moop->klass_name()->bytes(), 1665 moop->klass_name()->utf8_length(), 1666 (char *) moop->name()->bytes(), 1667 moop->name()->utf8_length(), 1668 (char *) moop->signature()->bytes(), 1669 moop->signature()->utf8_length(), 1670 insts_begin(), insts_size()); 1671 1672 if (JvmtiExport::should_post_compiled_method_load() || 1673 JvmtiExport::should_post_compiled_method_unload()) { 1674 get_and_cache_jmethod_id(); 1675 } 1676 1677 if (JvmtiExport::should_post_compiled_method_load()) { 1678 // Let the Service thread (which is a real Java thread) post the event 1679 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1680 JvmtiDeferredEventQueue::enqueue( 1681 JvmtiDeferredEvent::compiled_method_load_event(this)); 1682 } 1683 } 1684 1685 jmethodID nmethod::get_and_cache_jmethod_id() { 1686 if (_jmethod_id == NULL) { 1687 // Cache the jmethod_id since it can no longer be looked up once the 1688 // method itself has been marked for unloading. 1689 _jmethod_id = method()->jmethod_id(); 1690 } 1691 return _jmethod_id; 1692 } 1693 1694 void nmethod::post_compiled_method_unload() { 1695 if (unload_reported()) { 1696 // During unloading we transition to unloaded and then to zombie 1697 // and the unloading is reported during the first transition. 1698 return; 1699 } 1700 1701 assert(_method != NULL && !is_unloaded(), "just checking"); 1702 DTRACE_METHOD_UNLOAD_PROBE(method()); 1703 1704 // If a JVMTI agent has enabled the CompiledMethodUnload event then 1705 // post the event. Sometime later this nmethod will be made a zombie 1706 // by the sweeper but the Method* will not be valid at that point. 1707 // If the _jmethod_id is null then no load event was ever requested 1708 // so don't bother posting the unload. The main reason for this is 1709 // that the jmethodID is a weak reference to the Method* so if 1710 // it's being unloaded there's no way to look it up since the weak 1711 // ref will have been cleared. 1712 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) { 1713 assert(!unload_reported(), "already unloaded"); 1714 JvmtiDeferredEvent event = 1715 JvmtiDeferredEvent::compiled_method_unload_event(this, 1716 _jmethod_id, insts_begin()); 1717 if (SafepointSynchronize::is_at_safepoint()) { 1718 // Don't want to take the queueing lock. Add it as pending and 1719 // it will get enqueued later. 1720 JvmtiDeferredEventQueue::add_pending_event(event); 1721 } else { 1722 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); 1723 JvmtiDeferredEventQueue::enqueue(event); 1724 } 1725 } 1726 1727 // The JVMTI CompiledMethodUnload event can be enabled or disabled at 1728 // any time. As the nmethod is being unloaded now we mark it has 1729 // having the unload event reported - this will ensure that we don't 1730 // attempt to report the event in the unlikely scenario where the 1731 // event is enabled at the time the nmethod is made a zombie. 1732 set_unload_reported(); 1733 } 1734 1735 void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) { 1736 if (ic->is_icholder_call()) { 1737 // The only exception is compiledICHolder oops which may 1738 // yet be marked below. (We check this further below). 1739 CompiledICHolder* cichk_oop = ic->cached_icholder(); 1740 1741 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) && 1742 cichk_oop->holder_klass()->is_loader_alive(is_alive)) { 1743 return; 1744 } 1745 } else { 1746 Metadata* ic_oop = ic->cached_metadata(); 1747 if (ic_oop != NULL) { 1748 if (ic_oop->is_klass()) { 1749 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) { 1750 return; 1751 } 1752 } else if (ic_oop->is_method()) { 1753 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) { 1754 return; 1755 } 1756 } else { 1757 ShouldNotReachHere(); 1758 } 1759 } 1760 } 1761 1762 ic->set_to_clean(); 1763 } 1764 1765 // This is called at the end of the strong tracing/marking phase of a 1766 // GC to unload an nmethod if it contains otherwise unreachable 1767 // oops. 1768 1769 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) { 1770 // Make sure the oop's ready to receive visitors 1771 assert(!is_zombie() && !is_unloaded(), 1772 "should not call follow on zombie or unloaded nmethod"); 1773 1774 // If the method is not entrant then a JMP is plastered over the 1775 // first few bytes. If an oop in the old code was there, that oop 1776 // should not get GC'd. Skip the first few bytes of oops on 1777 // not-entrant methods. 1778 address low_boundary = verified_entry_point(); 1779 if (is_not_entrant()) { 1780 low_boundary += NativeJump::instruction_size; 1781 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1782 // (See comment above.) 1783 } 1784 1785 // The RedefineClasses() API can cause the class unloading invariant 1786 // to no longer be true. See jvmtiExport.hpp for details. 1787 // Also, leave a debugging breadcrumb in local flag. 1788 if (JvmtiExport::has_redefined_a_class()) { 1789 // This set of the unloading_occurred flag is done before the 1790 // call to post_compiled_method_unload() so that the unloading 1791 // of this nmethod is reported. 1792 unloading_occurred = true; 1793 } 1794 1795 // Exception cache 1796 clean_exception_cache(is_alive); 1797 1798 // If class unloading occurred we first iterate over all inline caches and 1799 // clear ICs where the cached oop is referring to an unloaded klass or method. 1800 // The remaining live cached oops will be traversed in the relocInfo::oop_type 1801 // iteration below. 1802 if (unloading_occurred) { 1803 RelocIterator iter(this, low_boundary); 1804 while(iter.next()) { 1805 if (iter.type() == relocInfo::virtual_call_type) { 1806 CompiledIC *ic = CompiledIC_at(&iter); 1807 clean_ic_if_metadata_is_dead(ic, is_alive); 1808 } 1809 } 1810 } 1811 1812 // Compiled code 1813 { 1814 RelocIterator iter(this, low_boundary); 1815 while (iter.next()) { 1816 if (iter.type() == relocInfo::oop_type) { 1817 oop_Relocation* r = iter.oop_reloc(); 1818 // In this loop, we must only traverse those oops directly embedded in 1819 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 1820 assert(1 == (r->oop_is_immediate()) + 1821 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1822 "oop must be found in exactly one place"); 1823 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1824 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) { 1825 return; 1826 } 1827 } 1828 } 1829 } 1830 } 1831 1832 1833 // Scopes 1834 for (oop* p = oops_begin(); p < oops_end(); p++) { 1835 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1836 if (can_unload(is_alive, p, unloading_occurred)) { 1837 return; 1838 } 1839 } 1840 1841 #if INCLUDE_JVMCI 1842 // Follow JVMCI method 1843 BarrierSet* bs = Universe::heap()->barrier_set(); 1844 if (_jvmci_installed_code != NULL) { 1845 if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) { 1846 if (!is_alive->do_object_b(_jvmci_installed_code)) { 1847 clear_jvmci_installed_code(); 1848 } 1849 } else { 1850 if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) { 1851 return; 1852 } 1853 } 1854 } 1855 1856 if (_speculation_log != NULL) { 1857 if (!is_alive->do_object_b(_speculation_log)) { 1858 bs->write_ref_nmethod_pre(&_speculation_log, this); 1859 _speculation_log = NULL; 1860 bs->write_ref_nmethod_post(&_speculation_log, this); 1861 } 1862 } 1863 #endif 1864 1865 1866 // Ensure that all metadata is still alive 1867 verify_metadata_loaders(low_boundary, is_alive); 1868 } 1869 1870 template <class CompiledICorStaticCall> 1871 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, nmethod* from) { 1872 // Ok, to lookup references to zombies here 1873 CodeBlob *cb = CodeCache::find_blob_unsafe(addr); 1874 if (cb != NULL && cb->is_nmethod()) { 1875 nmethod* nm = (nmethod*)cb; 1876 1877 if (nm->unloading_clock() != nmethod::global_unloading_clock()) { 1878 // The nmethod has not been processed yet. 1879 return true; 1880 } 1881 1882 // Clean inline caches pointing to both zombie and not_entrant methods 1883 if (!nm->is_in_use() || (nm->method()->code() != nm)) { 1884 ic->set_to_clean(); 1885 assert(ic->is_clean(), "nmethod " PTR_FORMAT "not clean %s", p2i(from), from->method()->name_and_sig_as_C_string()); 1886 } 1887 } 1888 1889 return false; 1890 } 1891 1892 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, nmethod* from) { 1893 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from); 1894 } 1895 1896 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) { 1897 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from); 1898 } 1899 1900 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) { 1901 assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type"); 1902 1903 oop_Relocation* r = iter_at_oop->oop_reloc(); 1904 // Traverse those oops directly embedded in the code. 1905 // Other oops (oop_index>0) are seen as part of scopes_oops. 1906 assert(1 == (r->oop_is_immediate()) + 1907 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 1908 "oop must be found in exactly one place"); 1909 if (r->oop_is_immediate() && r->oop_value() != NULL) { 1910 // Unload this nmethod if the oop is dead. 1911 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) { 1912 return true;; 1913 } 1914 } 1915 1916 return false; 1917 } 1918 1919 1920 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) { 1921 ResourceMark rm; 1922 1923 // Make sure the oop's ready to receive visitors 1924 assert(!is_zombie() && !is_unloaded(), 1925 "should not call follow on zombie or unloaded nmethod"); 1926 1927 // If the method is not entrant then a JMP is plastered over the 1928 // first few bytes. If an oop in the old code was there, that oop 1929 // should not get GC'd. Skip the first few bytes of oops on 1930 // not-entrant methods. 1931 address low_boundary = verified_entry_point(); 1932 if (is_not_entrant()) { 1933 low_boundary += NativeJump::instruction_size; 1934 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 1935 // (See comment above.) 1936 } 1937 1938 // The RedefineClasses() API can cause the class unloading invariant 1939 // to no longer be true. See jvmtiExport.hpp for details. 1940 // Also, leave a debugging breadcrumb in local flag. 1941 if (JvmtiExport::has_redefined_a_class()) { 1942 // This set of the unloading_occurred flag is done before the 1943 // call to post_compiled_method_unload() so that the unloading 1944 // of this nmethod is reported. 1945 unloading_occurred = true; 1946 } 1947 1948 // Exception cache 1949 clean_exception_cache(is_alive); 1950 1951 bool is_unloaded = false; 1952 bool postponed = false; 1953 1954 RelocIterator iter(this, low_boundary); 1955 while(iter.next()) { 1956 1957 switch (iter.type()) { 1958 1959 case relocInfo::virtual_call_type: 1960 if (unloading_occurred) { 1961 // If class unloading occurred we first iterate over all inline caches and 1962 // clear ICs where the cached oop is referring to an unloaded klass or method. 1963 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive); 1964 } 1965 1966 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this); 1967 break; 1968 1969 case relocInfo::opt_virtual_call_type: 1970 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this); 1971 break; 1972 1973 case relocInfo::static_call_type: 1974 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this); 1975 break; 1976 1977 case relocInfo::oop_type: 1978 if (!is_unloaded) { 1979 is_unloaded = unload_if_dead_at(&iter, is_alive, unloading_occurred); 1980 } 1981 break; 1982 1983 case relocInfo::metadata_type: 1984 break; // nothing to do. 1985 } 1986 } 1987 1988 if (is_unloaded) { 1989 return postponed; 1990 } 1991 1992 // Scopes 1993 for (oop* p = oops_begin(); p < oops_end(); p++) { 1994 if (*p == Universe::non_oop_word()) continue; // skip non-oops 1995 if (can_unload(is_alive, p, unloading_occurred)) { 1996 is_unloaded = true; 1997 break; 1998 } 1999 } 2000 2001 if (is_unloaded) { 2002 return postponed; 2003 } 2004 2005 #if INCLUDE_JVMCI 2006 // Follow JVMCI method 2007 BarrierSet* bs = Universe::heap()->barrier_set(); 2008 if (_jvmci_installed_code != NULL) { 2009 if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) { 2010 if (!is_alive->do_object_b(_jvmci_installed_code)) { 2011 clear_jvmci_installed_code(); 2012 } 2013 } else { 2014 if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) { 2015 is_unloaded = true; 2016 } 2017 } 2018 } 2019 2020 if (_speculation_log != NULL) { 2021 if (!is_alive->do_object_b(_speculation_log)) { 2022 bs->write_ref_nmethod_pre(&_speculation_log, this); 2023 _speculation_log = NULL; 2024 bs->write_ref_nmethod_post(&_speculation_log, this); 2025 } 2026 } 2027 #endif 2028 2029 // Ensure that all metadata is still alive 2030 verify_metadata_loaders(low_boundary, is_alive); 2031 2032 return postponed; 2033 } 2034 2035 void nmethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) { 2036 ResourceMark rm; 2037 2038 // Make sure the oop's ready to receive visitors 2039 assert(!is_zombie(), 2040 "should not call follow on zombie nmethod"); 2041 2042 // If the method is not entrant then a JMP is plastered over the 2043 // first few bytes. If an oop in the old code was there, that oop 2044 // should not get GC'd. Skip the first few bytes of oops on 2045 // not-entrant methods. 2046 address low_boundary = verified_entry_point(); 2047 if (is_not_entrant()) { 2048 low_boundary += NativeJump::instruction_size; 2049 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 2050 // (See comment above.) 2051 } 2052 2053 RelocIterator iter(this, low_boundary); 2054 while(iter.next()) { 2055 2056 switch (iter.type()) { 2057 2058 case relocInfo::virtual_call_type: 2059 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this); 2060 break; 2061 2062 case relocInfo::opt_virtual_call_type: 2063 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this); 2064 break; 2065 2066 case relocInfo::static_call_type: 2067 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this); 2068 break; 2069 } 2070 } 2071 } 2072 2073 #ifdef ASSERT 2074 2075 class CheckClass : AllStatic { 2076 static BoolObjectClosure* _is_alive; 2077 2078 // Check class_loader is alive for this bit of metadata. 2079 static void check_class(Metadata* md) { 2080 Klass* klass = NULL; 2081 if (md->is_klass()) { 2082 klass = ((Klass*)md); 2083 } else if (md->is_method()) { 2084 klass = ((Method*)md)->method_holder(); 2085 } else if (md->is_methodData()) { 2086 klass = ((MethodData*)md)->method()->method_holder(); 2087 } else { 2088 md->print(); 2089 ShouldNotReachHere(); 2090 } 2091 assert(klass->is_loader_alive(_is_alive), "must be alive"); 2092 } 2093 public: 2094 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) { 2095 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint"); 2096 _is_alive = is_alive; 2097 nm->metadata_do(check_class); 2098 } 2099 }; 2100 2101 // This is called during a safepoint so can use static data 2102 BoolObjectClosure* CheckClass::_is_alive = NULL; 2103 #endif // ASSERT 2104 2105 2106 // Processing of oop references should have been sufficient to keep 2107 // all strong references alive. Any weak references should have been 2108 // cleared as well. Visit all the metadata and ensure that it's 2109 // really alive. 2110 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) { 2111 #ifdef ASSERT 2112 RelocIterator iter(this, low_boundary); 2113 while (iter.next()) { 2114 // static_stub_Relocations may have dangling references to 2115 // Method*s so trim them out here. Otherwise it looks like 2116 // compiled code is maintaining a link to dead metadata. 2117 address static_call_addr = NULL; 2118 if (iter.type() == relocInfo::opt_virtual_call_type) { 2119 CompiledIC* cic = CompiledIC_at(&iter); 2120 if (!cic->is_call_to_interpreted()) { 2121 static_call_addr = iter.addr(); 2122 } 2123 } else if (iter.type() == relocInfo::static_call_type) { 2124 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc()); 2125 if (!csc->is_call_to_interpreted()) { 2126 static_call_addr = iter.addr(); 2127 } 2128 } 2129 if (static_call_addr != NULL) { 2130 RelocIterator sciter(this, low_boundary); 2131 while (sciter.next()) { 2132 if (sciter.type() == relocInfo::static_stub_type && 2133 sciter.static_stub_reloc()->static_call() == static_call_addr) { 2134 sciter.static_stub_reloc()->clear_inline_cache(); 2135 } 2136 } 2137 } 2138 } 2139 // Check that the metadata embedded in the nmethod is alive 2140 CheckClass::do_check_class(is_alive, this); 2141 #endif 2142 } 2143 2144 2145 // Iterate over metadata calling this function. Used by RedefineClasses 2146 void nmethod::metadata_do(void f(Metadata*)) { 2147 address low_boundary = verified_entry_point(); 2148 if (is_not_entrant()) { 2149 low_boundary += NativeJump::instruction_size; 2150 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 2151 // (See comment above.) 2152 } 2153 { 2154 // Visit all immediate references that are embedded in the instruction stream. 2155 RelocIterator iter(this, low_boundary); 2156 while (iter.next()) { 2157 if (iter.type() == relocInfo::metadata_type ) { 2158 metadata_Relocation* r = iter.metadata_reloc(); 2159 // In this metadata, we must only follow those metadatas directly embedded in 2160 // the code. Other metadatas (oop_index>0) are seen as part of 2161 // the metadata section below. 2162 assert(1 == (r->metadata_is_immediate()) + 2163 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), 2164 "metadata must be found in exactly one place"); 2165 if (r->metadata_is_immediate() && r->metadata_value() != NULL) { 2166 Metadata* md = r->metadata_value(); 2167 if (md != _method) f(md); 2168 } 2169 } else if (iter.type() == relocInfo::virtual_call_type) { 2170 // Check compiledIC holders associated with this nmethod 2171 CompiledIC *ic = CompiledIC_at(&iter); 2172 if (ic->is_icholder_call()) { 2173 CompiledICHolder* cichk = ic->cached_icholder(); 2174 f(cichk->holder_method()); 2175 f(cichk->holder_klass()); 2176 } else { 2177 Metadata* ic_oop = ic->cached_metadata(); 2178 if (ic_oop != NULL) { 2179 f(ic_oop); 2180 } 2181 } 2182 } 2183 } 2184 } 2185 2186 // Visit the metadata section 2187 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { 2188 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops 2189 Metadata* md = *p; 2190 f(md); 2191 } 2192 2193 // Visit metadata not embedded in the other places. 2194 if (_method != NULL) f(_method); 2195 } 2196 2197 void nmethod::oops_do(OopClosure* f, bool allow_zombie) { 2198 // make sure the oops ready to receive visitors 2199 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod"); 2200 assert(!is_unloaded(), "should not call follow on unloaded nmethod"); 2201 2202 // If the method is not entrant or zombie then a JMP is plastered over the 2203 // first few bytes. If an oop in the old code was there, that oop 2204 // should not get GC'd. Skip the first few bytes of oops on 2205 // not-entrant methods. 2206 address low_boundary = verified_entry_point(); 2207 if (is_not_entrant()) { 2208 low_boundary += NativeJump::instruction_size; 2209 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump. 2210 // (See comment above.) 2211 } 2212 2213 #if INCLUDE_JVMCI 2214 if (_jvmci_installed_code != NULL) { 2215 f->do_oop((oop*) &_jvmci_installed_code); 2216 } 2217 if (_speculation_log != NULL) { 2218 f->do_oop((oop*) &_speculation_log); 2219 } 2220 #endif 2221 2222 RelocIterator iter(this, low_boundary); 2223 2224 while (iter.next()) { 2225 if (iter.type() == relocInfo::oop_type ) { 2226 oop_Relocation* r = iter.oop_reloc(); 2227 // In this loop, we must only follow those oops directly embedded in 2228 // the code. Other oops (oop_index>0) are seen as part of scopes_oops. 2229 assert(1 == (r->oop_is_immediate()) + 2230 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), 2231 "oop must be found in exactly one place"); 2232 if (r->oop_is_immediate() && r->oop_value() != NULL) { 2233 f->do_oop(r->oop_addr()); 2234 } 2235 } 2236 } 2237 2238 // Scopes 2239 // This includes oop constants not inlined in the code stream. 2240 for (oop* p = oops_begin(); p < oops_end(); p++) { 2241 if (*p == Universe::non_oop_word()) continue; // skip non-oops 2242 f->do_oop(p); 2243 } 2244 } 2245 2246 #define NMETHOD_SENTINEL ((nmethod*)badAddress) 2247 2248 nmethod* volatile nmethod::_oops_do_mark_nmethods; 2249 2250 // An nmethod is "marked" if its _mark_link is set non-null. 2251 // Even if it is the end of the linked list, it will have a non-null link value, 2252 // as long as it is on the list. 2253 // This code must be MP safe, because it is used from parallel GC passes. 2254 bool nmethod::test_set_oops_do_mark() { 2255 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called"); 2256 nmethod* observed_mark_link = _oops_do_mark_link; 2257 if (observed_mark_link == NULL) { 2258 // Claim this nmethod for this thread to mark. 2259 observed_mark_link = (nmethod*) 2260 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL); 2261 if (observed_mark_link == NULL) { 2262 2263 // Atomically append this nmethod (now claimed) to the head of the list: 2264 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods; 2265 for (;;) { 2266 nmethod* required_mark_nmethods = observed_mark_nmethods; 2267 _oops_do_mark_link = required_mark_nmethods; 2268 observed_mark_nmethods = (nmethod*) 2269 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods); 2270 if (observed_mark_nmethods == required_mark_nmethods) 2271 break; 2272 } 2273 // Mark was clear when we first saw this guy. 2274 if (TraceScavenge) { print_on(tty, "oops_do, mark"); } 2275 return false; 2276 } 2277 } 2278 // On fall through, another racing thread marked this nmethod before we did. 2279 return true; 2280 } 2281 2282 void nmethod::oops_do_marking_prologue() { 2283 if (TraceScavenge) { tty->print_cr("[oops_do_marking_prologue"); } 2284 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row"); 2285 // We use cmpxchg_ptr instead of regular assignment here because the user 2286 // may fork a bunch of threads, and we need them all to see the same state. 2287 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL); 2288 guarantee(observed == NULL, "no races in this sequential code"); 2289 } 2290 2291 void nmethod::oops_do_marking_epilogue() { 2292 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row"); 2293 nmethod* cur = _oops_do_mark_nmethods; 2294 while (cur != NMETHOD_SENTINEL) { 2295 assert(cur != NULL, "not NULL-terminated"); 2296 nmethod* next = cur->_oops_do_mark_link; 2297 cur->_oops_do_mark_link = NULL; 2298 DEBUG_ONLY(cur->verify_oop_relocations()); 2299 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark")); 2300 cur = next; 2301 } 2302 void* required = _oops_do_mark_nmethods; 2303 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required); 2304 guarantee(observed == required, "no races in this sequential code"); 2305 if (TraceScavenge) { tty->print_cr("oops_do_marking_epilogue]"); } 2306 } 2307 2308 class DetectScavengeRoot: public OopClosure { 2309 bool _detected_scavenge_root; 2310 public: 2311 DetectScavengeRoot() : _detected_scavenge_root(false) 2312 { NOT_PRODUCT(_print_nm = NULL); } 2313 bool detected_scavenge_root() { return _detected_scavenge_root; } 2314 virtual void do_oop(oop* p) { 2315 if ((*p) != NULL && (*p)->is_scavengable()) { 2316 NOT_PRODUCT(maybe_print(p)); 2317 _detected_scavenge_root = true; 2318 } 2319 } 2320 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2321 2322 #ifndef PRODUCT 2323 nmethod* _print_nm; 2324 void maybe_print(oop* p) { 2325 if (_print_nm == NULL) return; 2326 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root"); 2327 tty->print_cr("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ")", 2328 p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm), 2329 p2i(*p), p2i(p)); 2330 (*p)->print(); 2331 } 2332 #endif //PRODUCT 2333 }; 2334 2335 bool nmethod::detect_scavenge_root_oops() { 2336 DetectScavengeRoot detect_scavenge_root; 2337 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this); 2338 oops_do(&detect_scavenge_root); 2339 return detect_scavenge_root.detected_scavenge_root(); 2340 } 2341 2342 // Method that knows how to preserve outgoing arguments at call. This method must be 2343 // called with a frame corresponding to a Java invoke 2344 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { 2345 #ifndef SHARK 2346 if (method() != NULL && !method()->is_native()) { 2347 address pc = fr.pc(); 2348 SimpleScopeDesc ssd(this, pc); 2349 Bytecode_invoke call(ssd.method(), ssd.bci()); 2350 bool has_receiver = call.has_receiver(); 2351 bool has_appendix = call.has_appendix(); 2352 Symbol* signature = call.signature(); 2353 2354 // The method attached by JIT-compilers should be used, if present. 2355 // Bytecode can be inaccurate in such case. 2356 Method* callee = attached_method_before_pc(pc); 2357 if (callee != NULL) { 2358 has_receiver = !(callee->access_flags().is_static()); 2359 has_appendix = false; 2360 signature = callee->signature(); 2361 } 2362 2363 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f); 2364 } 2365 #endif // !SHARK 2366 } 2367 2368 inline bool includes(void* p, void* from, void* to) { 2369 return from <= p && p < to; 2370 } 2371 2372 2373 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) { 2374 assert(count >= 2, "must be sentinel values, at least"); 2375 2376 #ifdef ASSERT 2377 // must be sorted and unique; we do a binary search in find_pc_desc() 2378 int prev_offset = pcs[0].pc_offset(); 2379 assert(prev_offset == PcDesc::lower_offset_limit, 2380 "must start with a sentinel"); 2381 for (int i = 1; i < count; i++) { 2382 int this_offset = pcs[i].pc_offset(); 2383 assert(this_offset > prev_offset, "offsets must be sorted"); 2384 prev_offset = this_offset; 2385 } 2386 assert(prev_offset == PcDesc::upper_offset_limit, 2387 "must end with a sentinel"); 2388 #endif //ASSERT 2389 2390 // Search for MethodHandle invokes and tag the nmethod. 2391 for (int i = 0; i < count; i++) { 2392 if (pcs[i].is_method_handle_invoke()) { 2393 set_has_method_handle_invokes(true); 2394 break; 2395 } 2396 } 2397 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler"); 2398 2399 int size = count * sizeof(PcDesc); 2400 assert(scopes_pcs_size() >= size, "oob"); 2401 memcpy(scopes_pcs_begin(), pcs, size); 2402 2403 // Adjust the final sentinel downward. 2404 PcDesc* last_pc = &scopes_pcs_begin()[count-1]; 2405 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity"); 2406 last_pc->set_pc_offset(content_size() + 1); 2407 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { 2408 // Fill any rounding gaps with copies of the last record. 2409 last_pc[1] = last_pc[0]; 2410 } 2411 // The following assert could fail if sizeof(PcDesc) is not 2412 // an integral multiple of oopSize (the rounding term). 2413 // If it fails, change the logic to always allocate a multiple 2414 // of sizeof(PcDesc), and fill unused words with copies of *last_pc. 2415 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly"); 2416 } 2417 2418 void nmethod::copy_scopes_data(u_char* buffer, int size) { 2419 assert(scopes_data_size() >= size, "oob"); 2420 memcpy(scopes_data_begin(), buffer, size); 2421 } 2422 2423 // When using JVMCI the address might be off by the size of a call instruction. 2424 bool nmethod::is_deopt_entry(address pc) { 2425 return pc == deopt_handler_begin() 2426 #if INCLUDE_JVMCI 2427 || pc == (deopt_handler_begin() + NativeCall::instruction_size) 2428 #endif 2429 ; 2430 } 2431 2432 #ifdef ASSERT 2433 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) { 2434 PcDesc* lower = nm->scopes_pcs_begin(); 2435 PcDesc* upper = nm->scopes_pcs_end(); 2436 lower += 1; // exclude initial sentinel 2437 PcDesc* res = NULL; 2438 for (PcDesc* p = lower; p < upper; p++) { 2439 NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests); // don't count this call to match_desc 2440 if (match_desc(p, pc_offset, approximate)) { 2441 if (res == NULL) 2442 res = p; 2443 else 2444 res = (PcDesc*) badAddress; 2445 } 2446 } 2447 return res; 2448 } 2449 #endif 2450 2451 2452 // Finds a PcDesc with real-pc equal to "pc" 2453 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) { 2454 address base_address = code_begin(); 2455 if ((pc < base_address) || 2456 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { 2457 return NULL; // PC is wildly out of range 2458 } 2459 int pc_offset = (int) (pc - base_address); 2460 2461 // Check the PcDesc cache if it contains the desired PcDesc 2462 // (This as an almost 100% hit rate.) 2463 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); 2464 if (res != NULL) { 2465 assert(res == linear_search(this, pc_offset, approximate), "cache ok"); 2466 return res; 2467 } 2468 2469 // Fallback algorithm: quasi-linear search for the PcDesc 2470 // Find the last pc_offset less than the given offset. 2471 // The successor must be the required match, if there is a match at all. 2472 // (Use a fixed radix to avoid expensive affine pointer arithmetic.) 2473 PcDesc* lower = scopes_pcs_begin(); 2474 PcDesc* upper = scopes_pcs_end(); 2475 upper -= 1; // exclude final sentinel 2476 if (lower >= upper) return NULL; // native method; no PcDescs at all 2477 2478 #define assert_LU_OK \ 2479 /* invariant on lower..upper during the following search: */ \ 2480 assert(lower->pc_offset() < pc_offset, "sanity"); \ 2481 assert(upper->pc_offset() >= pc_offset, "sanity") 2482 assert_LU_OK; 2483 2484 // Use the last successful return as a split point. 2485 PcDesc* mid = _pc_desc_cache.last_pc_desc(); 2486 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); 2487 if (mid->pc_offset() < pc_offset) { 2488 lower = mid; 2489 } else { 2490 upper = mid; 2491 } 2492 2493 // Take giant steps at first (4096, then 256, then 16, then 1) 2494 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); 2495 const int RADIX = (1 << LOG2_RADIX); 2496 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { 2497 while ((mid = lower + step) < upper) { 2498 assert_LU_OK; 2499 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); 2500 if (mid->pc_offset() < pc_offset) { 2501 lower = mid; 2502 } else { 2503 upper = mid; 2504 break; 2505 } 2506 } 2507 assert_LU_OK; 2508 } 2509 2510 // Sneak up on the value with a linear search of length ~16. 2511 while (true) { 2512 assert_LU_OK; 2513 mid = lower + 1; 2514 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); 2515 if (mid->pc_offset() < pc_offset) { 2516 lower = mid; 2517 } else { 2518 upper = mid; 2519 break; 2520 } 2521 } 2522 #undef assert_LU_OK 2523 2524 if (match_desc(upper, pc_offset, approximate)) { 2525 assert(upper == linear_search(this, pc_offset, approximate), "search ok"); 2526 _pc_desc_cache.add_pc_desc(upper); 2527 return upper; 2528 } else { 2529 assert(NULL == linear_search(this, pc_offset, approximate), "search ok"); 2530 return NULL; 2531 } 2532 } 2533 2534 2535 void nmethod::check_all_dependencies(DepChange& changes) { 2536 // Checked dependencies are allocated into this ResourceMark 2537 ResourceMark rm; 2538 2539 // Turn off dependency tracing while actually testing dependencies. 2540 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) ); 2541 2542 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash, 2543 &DependencySignature::equals, 11027> DepTable; 2544 2545 DepTable* table = new DepTable(); 2546 2547 // Iterate over live nmethods and check dependencies of all nmethods that are not 2548 // marked for deoptimization. A particular dependency is only checked once. 2549 NMethodIterator iter; 2550 while(iter.next()) { 2551 nmethod* nm = iter.method(); 2552 // Only notify for live nmethods 2553 if (nm->is_alive() && !nm->is_marked_for_deoptimization()) { 2554 for (Dependencies::DepStream deps(nm); deps.next(); ) { 2555 // Construct abstraction of a dependency. 2556 DependencySignature* current_sig = new DependencySignature(deps); 2557 2558 // Determine if dependency is already checked. table->put(...) returns 2559 // 'true' if the dependency is added (i.e., was not in the hashtable). 2560 if (table->put(*current_sig, 1)) { 2561 if (deps.check_dependency() != NULL) { 2562 // Dependency checking failed. Print out information about the failed 2563 // dependency and finally fail with an assert. We can fail here, since 2564 // dependency checking is never done in a product build. 2565 tty->print_cr("Failed dependency:"); 2566 changes.print(); 2567 nm->print(); 2568 nm->print_dependencies(); 2569 assert(false, "Should have been marked for deoptimization"); 2570 } 2571 } 2572 } 2573 } 2574 } 2575 } 2576 2577 bool nmethod::check_dependency_on(DepChange& changes) { 2578 // What has happened: 2579 // 1) a new class dependee has been added 2580 // 2) dependee and all its super classes have been marked 2581 bool found_check = false; // set true if we are upset 2582 for (Dependencies::DepStream deps(this); deps.next(); ) { 2583 // Evaluate only relevant dependencies. 2584 if (deps.spot_check_dependency_at(changes) != NULL) { 2585 found_check = true; 2586 NOT_DEBUG(break); 2587 } 2588 } 2589 return found_check; 2590 } 2591 2592 bool nmethod::is_evol_dependent_on(Klass* dependee) { 2593 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee); 2594 Array<Method*>* dependee_methods = dependee_ik->methods(); 2595 for (Dependencies::DepStream deps(this); deps.next(); ) { 2596 if (deps.type() == Dependencies::evol_method) { 2597 Method* method = deps.method_argument(0); 2598 for (int j = 0; j < dependee_methods->length(); j++) { 2599 if (dependee_methods->at(j) == method) { 2600 // RC_TRACE macro has an embedded ResourceMark 2601 RC_TRACE(0x01000000, 2602 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)", 2603 _method->method_holder()->external_name(), 2604 _method->name()->as_C_string(), 2605 _method->signature()->as_C_string(), compile_id(), 2606 method->method_holder()->external_name(), 2607 method->name()->as_C_string(), 2608 method->signature()->as_C_string())); 2609 if (TraceDependencies || LogCompilation) 2610 deps.log_dependency(dependee); 2611 return true; 2612 } 2613 } 2614 } 2615 } 2616 return false; 2617 } 2618 2619 // Called from mark_for_deoptimization, when dependee is invalidated. 2620 bool nmethod::is_dependent_on_method(Method* dependee) { 2621 for (Dependencies::DepStream deps(this); deps.next(); ) { 2622 if (deps.type() != Dependencies::evol_method) 2623 continue; 2624 Method* method = deps.method_argument(0); 2625 if (method == dependee) return true; 2626 } 2627 return false; 2628 } 2629 2630 2631 bool nmethod::is_patchable_at(address instr_addr) { 2632 assert(insts_contains(instr_addr), "wrong nmethod used"); 2633 if (is_zombie()) { 2634 // a zombie may never be patched 2635 return false; 2636 } 2637 return true; 2638 } 2639 2640 2641 address nmethod::continuation_for_implicit_exception(address pc) { 2642 // Exception happened outside inline-cache check code => we are inside 2643 // an active nmethod => use cpc to determine a return address 2644 int exception_offset = pc - code_begin(); 2645 int cont_offset = ImplicitExceptionTable(this).at( exception_offset ); 2646 #ifdef ASSERT 2647 if (cont_offset == 0) { 2648 Thread* thread = Thread::current(); 2649 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY 2650 HandleMark hm(thread); 2651 ResourceMark rm(thread); 2652 CodeBlob* cb = CodeCache::find_blob(pc); 2653 assert(cb != NULL && cb == this, ""); 2654 ttyLocker ttyl; 2655 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc)); 2656 print(); 2657 method()->print_codes(); 2658 print_code(); 2659 print_pcs(); 2660 } 2661 #endif 2662 if (cont_offset == 0) { 2663 // Let the normal error handling report the exception 2664 return NULL; 2665 } 2666 return code_begin() + cont_offset; 2667 } 2668 2669 2670 2671 void nmethod_init() { 2672 // make sure you didn't forget to adjust the filler fields 2673 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word"); 2674 } 2675 2676 2677 //------------------------------------------------------------------------------------------- 2678 2679 2680 // QQQ might we make this work from a frame?? 2681 nmethodLocker::nmethodLocker(address pc) { 2682 CodeBlob* cb = CodeCache::find_blob(pc); 2683 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found"); 2684 _nm = (nmethod*)cb; 2685 lock_nmethod(_nm); 2686 } 2687 2688 // Only JvmtiDeferredEvent::compiled_method_unload_event() 2689 // should pass zombie_ok == true. 2690 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) { 2691 if (nm == NULL) return; 2692 Atomic::inc(&nm->_lock_count); 2693 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method"); 2694 } 2695 2696 void nmethodLocker::unlock_nmethod(nmethod* nm) { 2697 if (nm == NULL) return; 2698 Atomic::dec(&nm->_lock_count); 2699 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock"); 2700 } 2701 2702 // ----------------------------------------------------------------------------- 2703 // nmethod::get_deopt_original_pc 2704 // 2705 // Return the original PC for the given PC if: 2706 // (a) the given PC belongs to a nmethod and 2707 // (b) it is a deopt PC 2708 address nmethod::get_deopt_original_pc(const frame* fr) { 2709 if (fr->cb() == NULL) return NULL; 2710 2711 nmethod* nm = fr->cb()->as_nmethod_or_null(); 2712 if (nm != NULL && nm->is_deopt_pc(fr->pc())) 2713 return nm->get_original_pc(fr); 2714 2715 return NULL; 2716 } 2717 2718 2719 // ----------------------------------------------------------------------------- 2720 // MethodHandle 2721 2722 bool nmethod::is_method_handle_return(address return_pc) { 2723 if (!has_method_handle_invokes()) return false; 2724 PcDesc* pd = pc_desc_at(return_pc); 2725 if (pd == NULL) 2726 return false; 2727 return pd->is_method_handle_invoke(); 2728 } 2729 2730 2731 // ----------------------------------------------------------------------------- 2732 // Verification 2733 2734 class VerifyOopsClosure: public OopClosure { 2735 nmethod* _nm; 2736 bool _ok; 2737 public: 2738 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } 2739 bool ok() { return _ok; } 2740 virtual void do_oop(oop* p) { 2741 if ((*p) == NULL || (*p)->is_oop()) return; 2742 if (_ok) { 2743 _nm->print_nmethod(true); 2744 _ok = false; 2745 } 2746 tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)", 2747 p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm)); 2748 } 2749 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2750 }; 2751 2752 void nmethod::verify() { 2753 2754 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant 2755 // seems odd. 2756 2757 if (is_zombie() || is_not_entrant() || is_unloaded()) 2758 return; 2759 2760 // Make sure all the entry points are correctly aligned for patching. 2761 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point()); 2762 2763 // assert(method()->is_oop(), "must be valid"); 2764 2765 ResourceMark rm; 2766 2767 if (!CodeCache::contains(this)) { 2768 fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this)); 2769 } 2770 2771 if(is_native_method() ) 2772 return; 2773 2774 nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); 2775 if (nm != this) { 2776 fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this)); 2777 } 2778 2779 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2780 if (! p->verify(this)) { 2781 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this)); 2782 } 2783 } 2784 2785 VerifyOopsClosure voc(this); 2786 oops_do(&voc); 2787 assert(voc.ok(), "embedded oops must be OK"); 2788 verify_scavenge_root_oops(); 2789 2790 verify_scopes(); 2791 } 2792 2793 2794 void nmethod::verify_interrupt_point(address call_site) { 2795 // Verify IC only when nmethod installation is finished. 2796 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed 2797 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state 2798 if (is_installed) { 2799 Thread *cur = Thread::current(); 2800 if (CompiledIC_lock->owner() == cur || 2801 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) && 2802 SafepointSynchronize::is_at_safepoint())) { 2803 CompiledIC_at(this, call_site); 2804 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 2805 } else { 2806 MutexLocker ml_verify (CompiledIC_lock); 2807 CompiledIC_at(this, call_site); 2808 } 2809 } 2810 2811 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address()); 2812 assert(pd != NULL, "PcDesc must exist"); 2813 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(), 2814 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(), 2815 pd->return_oop()); 2816 !sd->is_top(); sd = sd->sender()) { 2817 sd->verify(); 2818 } 2819 } 2820 2821 void nmethod::verify_scopes() { 2822 if( !method() ) return; // Runtime stubs have no scope 2823 if (method()->is_native()) return; // Ignore stub methods. 2824 // iterate through all interrupt point 2825 // and verify the debug information is valid. 2826 RelocIterator iter((nmethod*)this); 2827 while (iter.next()) { 2828 address stub = NULL; 2829 switch (iter.type()) { 2830 case relocInfo::virtual_call_type: 2831 verify_interrupt_point(iter.addr()); 2832 break; 2833 case relocInfo::opt_virtual_call_type: 2834 stub = iter.opt_virtual_call_reloc()->static_stub(); 2835 verify_interrupt_point(iter.addr()); 2836 break; 2837 case relocInfo::static_call_type: 2838 stub = iter.static_call_reloc()->static_stub(); 2839 //verify_interrupt_point(iter.addr()); 2840 break; 2841 case relocInfo::runtime_call_type: 2842 address destination = iter.reloc()->value(); 2843 // Right now there is no way to find out which entries support 2844 // an interrupt point. It would be nice if we had this 2845 // information in a table. 2846 break; 2847 } 2848 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section"); 2849 } 2850 } 2851 2852 2853 // ----------------------------------------------------------------------------- 2854 // Non-product code 2855 #ifndef PRODUCT 2856 2857 class DebugScavengeRoot: public OopClosure { 2858 nmethod* _nm; 2859 bool _ok; 2860 public: 2861 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { } 2862 bool ok() { return _ok; } 2863 virtual void do_oop(oop* p) { 2864 if ((*p) == NULL || !(*p)->is_scavengable()) return; 2865 if (_ok) { 2866 _nm->print_nmethod(true); 2867 _ok = false; 2868 } 2869 tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)", 2870 p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm)); 2871 (*p)->print(); 2872 } 2873 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 2874 }; 2875 2876 void nmethod::verify_scavenge_root_oops() { 2877 if (UseG1GC) { 2878 return; 2879 } 2880 2881 if (!on_scavenge_root_list()) { 2882 // Actually look inside, to verify the claim that it's clean. 2883 DebugScavengeRoot debug_scavenge_root(this); 2884 oops_do(&debug_scavenge_root); 2885 if (!debug_scavenge_root.ok()) 2886 fatal("found an unadvertised bad scavengable oop in the code cache"); 2887 } 2888 assert(scavenge_root_not_marked(), ""); 2889 } 2890 2891 #endif // PRODUCT 2892 2893 // Printing operations 2894 2895 void nmethod::print() const { 2896 ResourceMark rm; 2897 ttyLocker ttyl; // keep the following output all in one block 2898 2899 tty->print("Compiled method "); 2900 2901 if (is_compiled_by_c1()) { 2902 tty->print("(c1) "); 2903 } else if (is_compiled_by_c2()) { 2904 tty->print("(c2) "); 2905 } else if (is_compiled_by_shark()) { 2906 tty->print("(shark) "); 2907 } else if (is_compiled_by_jvmci()) { 2908 tty->print("(JVMCI) "); 2909 } else { 2910 tty->print("(nm) "); 2911 } 2912 2913 print_on(tty, NULL); 2914 2915 if (WizardMode) { 2916 tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this)); 2917 tty->print(" for method " INTPTR_FORMAT , p2i(method())); 2918 tty->print(" { "); 2919 if (is_in_use()) tty->print("in_use "); 2920 if (is_not_entrant()) tty->print("not_entrant "); 2921 if (is_zombie()) tty->print("zombie "); 2922 if (is_unloaded()) tty->print("unloaded "); 2923 if (on_scavenge_root_list()) tty->print("scavenge_root "); 2924 tty->print_cr("}:"); 2925 } 2926 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2927 p2i(this), 2928 p2i(this) + size(), 2929 size()); 2930 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2931 p2i(relocation_begin()), 2932 p2i(relocation_end()), 2933 relocation_size()); 2934 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2935 p2i(consts_begin()), 2936 p2i(consts_end()), 2937 consts_size()); 2938 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2939 p2i(insts_begin()), 2940 p2i(insts_end()), 2941 insts_size()); 2942 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2943 p2i(stub_begin()), 2944 p2i(stub_end()), 2945 stub_size()); 2946 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2947 p2i(oops_begin()), 2948 p2i(oops_end()), 2949 oops_size()); 2950 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2951 p2i(metadata_begin()), 2952 p2i(metadata_end()), 2953 metadata_size()); 2954 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2955 p2i(scopes_data_begin()), 2956 p2i(scopes_data_end()), 2957 scopes_data_size()); 2958 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2959 p2i(scopes_pcs_begin()), 2960 p2i(scopes_pcs_end()), 2961 scopes_pcs_size()); 2962 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2963 p2i(dependencies_begin()), 2964 p2i(dependencies_end()), 2965 dependencies_size()); 2966 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2967 p2i(handler_table_begin()), 2968 p2i(handler_table_end()), 2969 handler_table_size()); 2970 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d", 2971 p2i(nul_chk_table_begin()), 2972 p2i(nul_chk_table_end()), 2973 nul_chk_table_size()); 2974 } 2975 2976 #ifndef PRODUCT 2977 2978 void nmethod::print_scopes() { 2979 // Find the first pc desc for all scopes in the code and print it. 2980 ResourceMark rm; 2981 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 2982 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) 2983 continue; 2984 2985 ScopeDesc* sd = scope_desc_at(p->real_pc(this)); 2986 while (sd != NULL) { 2987 sd->print_on(tty, p); 2988 sd = sd->sender(); 2989 } 2990 } 2991 } 2992 2993 void nmethod::print_dependencies() { 2994 ResourceMark rm; 2995 ttyLocker ttyl; // keep the following output all in one block 2996 tty->print_cr("Dependencies:"); 2997 for (Dependencies::DepStream deps(this); deps.next(); ) { 2998 deps.print_dependency(); 2999 Klass* ctxk = deps.context_type(); 3000 if (ctxk != NULL) { 3001 if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) { 3002 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name()); 3003 } 3004 } 3005 deps.log_dependency(); // put it into the xml log also 3006 } 3007 } 3008 3009 3010 void nmethod::print_relocations() { 3011 ResourceMark m; // in case methods get printed via the debugger 3012 tty->print_cr("relocations:"); 3013 RelocIterator iter(this); 3014 iter.print(); 3015 if (UseRelocIndex) { 3016 jint* index_end = (jint*)relocation_end() - 1; 3017 jint index_size = *index_end; 3018 jint* index_start = (jint*)( (address)index_end - index_size ); 3019 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", p2i(index_start), index_size); 3020 if (index_size > 0) { 3021 jint* ip; 3022 for (ip = index_start; ip+2 <= index_end; ip += 2) 3023 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT, 3024 ip[0], 3025 ip[1], 3026 p2i(header_end()+ip[0]), 3027 p2i(relocation_begin()-1+ip[1])); 3028 for (; ip < index_end; ip++) 3029 tty->print_cr(" (%d ?)", ip[0]); 3030 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", p2i(ip), *ip); 3031 ip++; 3032 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", p2i(ip)); 3033 } 3034 } 3035 } 3036 3037 3038 void nmethod::print_pcs() { 3039 ResourceMark m; // in case methods get printed via debugger 3040 tty->print_cr("pc-bytecode offsets:"); 3041 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { 3042 p->print(this); 3043 } 3044 } 3045 3046 void nmethod::print_recorded_oops() { 3047 tty->print_cr("Recorded oops:"); 3048 for (int i = 0; i < oops_count(); i++) { 3049 oop o = oop_at(i); 3050 tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o)); 3051 if (o == (oop)Universe::non_oop_word()) { 3052 tty->print("non-oop word"); 3053 } else { 3054 o->print_value(); 3055 } 3056 tty->cr(); 3057 } 3058 } 3059 3060 void nmethod::print_recorded_metadata() { 3061 tty->print_cr("Recorded metadata:"); 3062 for (int i = 0; i < metadata_count(); i++) { 3063 Metadata* m = metadata_at(i); 3064 tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m)); 3065 if (m == (Metadata*)Universe::non_oop_word()) { 3066 tty->print("non-metadata word"); 3067 } else { 3068 m->print_value_on_maybe_null(tty); 3069 } 3070 tty->cr(); 3071 } 3072 } 3073 3074 #endif // PRODUCT 3075 3076 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) { 3077 RelocIterator iter(this, begin, end); 3078 bool have_one = false; 3079 while (iter.next()) { 3080 have_one = true; 3081 switch (iter.type()) { 3082 case relocInfo::none: return "no_reloc"; 3083 case relocInfo::oop_type: { 3084 stringStream st; 3085 oop_Relocation* r = iter.oop_reloc(); 3086 oop obj = r->oop_value(); 3087 st.print("oop("); 3088 if (obj == NULL) st.print("NULL"); 3089 else obj->print_value_on(&st); 3090 st.print(")"); 3091 return st.as_string(); 3092 } 3093 case relocInfo::metadata_type: { 3094 stringStream st; 3095 metadata_Relocation* r = iter.metadata_reloc(); 3096 Metadata* obj = r->metadata_value(); 3097 st.print("metadata("); 3098 if (obj == NULL) st.print("NULL"); 3099 else obj->print_value_on(&st); 3100 st.print(")"); 3101 return st.as_string(); 3102 } 3103 case relocInfo::runtime_call_type: { 3104 stringStream st; 3105 st.print("runtime_call"); 3106 runtime_call_Relocation* r = iter.runtime_call_reloc(); 3107 address dest = r->destination(); 3108 CodeBlob* cb = CodeCache::find_blob(dest); 3109 if (cb != NULL) { 3110 st.print(" %s", cb->name()); 3111 } else { 3112 ResourceMark rm; 3113 const int buflen = 1024; 3114 char* buf = NEW_RESOURCE_ARRAY(char, buflen); 3115 int offset; 3116 if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) { 3117 st.print(" %s", buf); 3118 if (offset != 0) { 3119 st.print("+%d", offset); 3120 } 3121 } 3122 } 3123 return st.as_string(); 3124 } 3125 case relocInfo::virtual_call_type: { 3126 stringStream st; 3127 st.print_raw("virtual_call"); 3128 virtual_call_Relocation* r = iter.virtual_call_reloc(); 3129 Method* m = r->method_value(); 3130 if (m != NULL) { 3131 assert(m->is_method(), ""); 3132 m->print_short_name(&st); 3133 } 3134 return st.as_string(); 3135 } 3136 case relocInfo::opt_virtual_call_type: { 3137 stringStream st; 3138 st.print_raw("optimized virtual_call"); 3139 opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc(); 3140 Method* m = r->method_value(); 3141 if (m != NULL) { 3142 assert(m->is_method(), ""); 3143 m->print_short_name(&st); 3144 } 3145 return st.as_string(); 3146 } 3147 case relocInfo::static_call_type: { 3148 stringStream st; 3149 st.print_raw("static_call"); 3150 static_call_Relocation* r = iter.static_call_reloc(); 3151 Method* m = r->method_value(); 3152 if (m != NULL) { 3153 assert(m->is_method(), ""); 3154 m->print_short_name(&st); 3155 } 3156 return st.as_string(); 3157 } 3158 case relocInfo::static_stub_type: return "static_stub"; 3159 case relocInfo::external_word_type: return "external_word"; 3160 case relocInfo::internal_word_type: return "internal_word"; 3161 case relocInfo::section_word_type: return "section_word"; 3162 case relocInfo::poll_type: return "poll"; 3163 case relocInfo::poll_return_type: return "poll_return"; 3164 case relocInfo::type_mask: return "type_bit_mask"; 3165 } 3166 } 3167 return have_one ? "other" : NULL; 3168 } 3169 3170 // Return a the last scope in (begin..end] 3171 ScopeDesc* nmethod::scope_desc_in(address begin, address end) { 3172 PcDesc* p = pc_desc_near(begin+1); 3173 if (p != NULL && p->real_pc(this) <= end) { 3174 return new ScopeDesc(this, p->scope_decode_offset(), 3175 p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(), 3176 p->return_oop()); 3177 } 3178 return NULL; 3179 } 3180 3181 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const { 3182 if (block_begin == entry_point()) stream->print_cr("[Entry Point]"); 3183 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]"); 3184 if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin()) stream->print_cr("[Exception Handler]"); 3185 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]"); 3186 if (JVMCI_ONLY(_deoptimize_offset >= 0 &&) block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]"); 3187 3188 if (has_method_handle_invokes()) 3189 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]"); 3190 3191 if (block_begin == consts_begin()) stream->print_cr("[Constants]"); 3192 3193 if (block_begin == entry_point()) { 3194 methodHandle m = method(); 3195 if (m.not_null()) { 3196 stream->print(" # "); 3197 m->print_value_on(stream); 3198 stream->cr(); 3199 } 3200 if (m.not_null() && !is_osr_method()) { 3201 ResourceMark rm; 3202 int sizeargs = m->size_of_parameters(); 3203 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs); 3204 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs); 3205 { 3206 int sig_index = 0; 3207 if (!m->is_static()) 3208 sig_bt[sig_index++] = T_OBJECT; // 'this' 3209 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) { 3210 BasicType t = ss.type(); 3211 sig_bt[sig_index++] = t; 3212 if (type2size[t] == 2) { 3213 sig_bt[sig_index++] = T_VOID; 3214 } else { 3215 assert(type2size[t] == 1, "size is 1 or 2"); 3216 } 3217 } 3218 assert(sig_index == sizeargs, ""); 3219 } 3220 const char* spname = "sp"; // make arch-specific? 3221 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false); 3222 int stack_slot_offset = this->frame_size() * wordSize; 3223 int tab1 = 14, tab2 = 24; 3224 int sig_index = 0; 3225 int arg_index = (m->is_static() ? 0 : -1); 3226 bool did_old_sp = false; 3227 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) { 3228 bool at_this = (arg_index == -1); 3229 bool at_old_sp = false; 3230 BasicType t = (at_this ? T_OBJECT : ss.type()); 3231 assert(t == sig_bt[sig_index], "sigs in sync"); 3232 if (at_this) 3233 stream->print(" # this: "); 3234 else 3235 stream->print(" # parm%d: ", arg_index); 3236 stream->move_to(tab1); 3237 VMReg fst = regs[sig_index].first(); 3238 VMReg snd = regs[sig_index].second(); 3239 if (fst->is_reg()) { 3240 stream->print("%s", fst->name()); 3241 if (snd->is_valid()) { 3242 stream->print(":%s", snd->name()); 3243 } 3244 } else if (fst->is_stack()) { 3245 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset; 3246 if (offset == stack_slot_offset) at_old_sp = true; 3247 stream->print("[%s+0x%x]", spname, offset); 3248 } else { 3249 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd); 3250 } 3251 stream->print(" "); 3252 stream->move_to(tab2); 3253 stream->print("= "); 3254 if (at_this) { 3255 m->method_holder()->print_value_on(stream); 3256 } else { 3257 bool did_name = false; 3258 if (!at_this && ss.is_object()) { 3259 Symbol* name = ss.as_symbol_or_null(); 3260 if (name != NULL) { 3261 name->print_value_on(stream); 3262 did_name = true; 3263 } 3264 } 3265 if (!did_name) 3266 stream->print("%s", type2name(t)); 3267 } 3268 if (at_old_sp) { 3269 stream->print(" (%s of caller)", spname); 3270 did_old_sp = true; 3271 } 3272 stream->cr(); 3273 sig_index += type2size[t]; 3274 arg_index += 1; 3275 if (!at_this) ss.next(); 3276 } 3277 if (!did_old_sp) { 3278 stream->print(" # "); 3279 stream->move_to(tab1); 3280 stream->print("[%s+0x%x]", spname, stack_slot_offset); 3281 stream->print(" (%s of caller)", spname); 3282 stream->cr(); 3283 } 3284 } 3285 } 3286 } 3287 3288 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) { 3289 // First, find an oopmap in (begin, end]. 3290 // We use the odd half-closed interval so that oop maps and scope descs 3291 // which are tied to the byte after a call are printed with the call itself. 3292 address base = code_begin(); 3293 ImmutableOopMapSet* oms = oop_maps(); 3294 if (oms != NULL) { 3295 for (int i = 0, imax = oms->count(); i < imax; i++) { 3296 const ImmutableOopMapPair* pair = oms->pair_at(i); 3297 const ImmutableOopMap* om = pair->get_from(oms); 3298 address pc = base + pair->pc_offset(); 3299 if (pc > begin) { 3300 if (pc <= end) { 3301 st->move_to(column); 3302 st->print("; "); 3303 om->print_on(st); 3304 } 3305 break; 3306 } 3307 } 3308 } 3309 3310 // Print any debug info present at this pc. 3311 ScopeDesc* sd = scope_desc_in(begin, end); 3312 if (sd != NULL) { 3313 st->move_to(column); 3314 if (sd->bci() == SynchronizationEntryBCI) { 3315 st->print(";*synchronization entry"); 3316 } else { 3317 if (sd->method() == NULL) { 3318 st->print("method is NULL"); 3319 } else if (sd->method()->is_native()) { 3320 st->print("method is native"); 3321 } else { 3322 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci()); 3323 st->print(";*%s", Bytecodes::name(bc)); 3324 switch (bc) { 3325 case Bytecodes::_invokevirtual: 3326 case Bytecodes::_invokespecial: 3327 case Bytecodes::_invokestatic: 3328 case Bytecodes::_invokeinterface: 3329 { 3330 Bytecode_invoke invoke(sd->method(), sd->bci()); 3331 st->print(" "); 3332 if (invoke.name() != NULL) 3333 invoke.name()->print_symbol_on(st); 3334 else 3335 st->print("<UNKNOWN>"); 3336 break; 3337 } 3338 case Bytecodes::_getfield: 3339 case Bytecodes::_putfield: 3340 case Bytecodes::_getstatic: 3341 case Bytecodes::_putstatic: 3342 { 3343 Bytecode_field field(sd->method(), sd->bci()); 3344 st->print(" "); 3345 if (field.name() != NULL) 3346 field.name()->print_symbol_on(st); 3347 else 3348 st->print("<UNKNOWN>"); 3349 } 3350 } 3351 } 3352 st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop()); 3353 } 3354 3355 // Print all scopes 3356 for (;sd != NULL; sd = sd->sender()) { 3357 st->move_to(column); 3358 st->print("; -"); 3359 if (sd->method() == NULL) { 3360 st->print("method is NULL"); 3361 } else { 3362 sd->method()->print_short_name(st); 3363 } 3364 int lineno = sd->method()->line_number_from_bci(sd->bci()); 3365 if (lineno != -1) { 3366 st->print("@%d (line %d)", sd->bci(), lineno); 3367 } else { 3368 st->print("@%d", sd->bci()); 3369 } 3370 st->cr(); 3371 } 3372 } 3373 3374 // Print relocation information 3375 const char* str = reloc_string_for(begin, end); 3376 if (str != NULL) { 3377 if (sd != NULL) st->cr(); 3378 st->move_to(column); 3379 st->print("; {%s}", str); 3380 } 3381 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin()); 3382 if (cont_offset != 0) { 3383 st->move_to(column); 3384 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset)); 3385 } 3386 3387 } 3388 3389 #ifndef PRODUCT 3390 3391 void nmethod::print_value_on(outputStream* st) const { 3392 st->print("nmethod"); 3393 print_on(st, NULL); 3394 } 3395 3396 void nmethod::print_calls(outputStream* st) { 3397 RelocIterator iter(this); 3398 while (iter.next()) { 3399 switch (iter.type()) { 3400 case relocInfo::virtual_call_type: 3401 case relocInfo::opt_virtual_call_type: { 3402 VerifyMutexLocker mc(CompiledIC_lock); 3403 CompiledIC_at(&iter)->print(); 3404 break; 3405 } 3406 case relocInfo::static_call_type: 3407 st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr())); 3408 compiledStaticCall_at(iter.reloc())->print(); 3409 break; 3410 } 3411 } 3412 } 3413 3414 void nmethod::print_handler_table() { 3415 ExceptionHandlerTable(this).print(); 3416 } 3417 3418 void nmethod::print_nul_chk_table() { 3419 ImplicitExceptionTable(this).print(code_begin()); 3420 } 3421 3422 void nmethod::print_statistics() { 3423 ttyLocker ttyl; 3424 if (xtty != NULL) xtty->head("statistics type='nmethod'"); 3425 native_nmethod_stats.print_native_nmethod_stats(); 3426 #ifdef COMPILER1 3427 c1_java_nmethod_stats.print_nmethod_stats("C1"); 3428 #endif 3429 #ifdef COMPILER2 3430 c2_java_nmethod_stats.print_nmethod_stats("C2"); 3431 #endif 3432 #if INCLUDE_JVMCI 3433 jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI"); 3434 #endif 3435 #ifdef SHARK 3436 shark_java_nmethod_stats.print_nmethod_stats("Shark"); 3437 #endif 3438 unknown_java_nmethod_stats.print_nmethod_stats("Unknown"); 3439 DebugInformationRecorder::print_statistics(); 3440 #ifndef PRODUCT 3441 pc_nmethod_stats.print_pc_stats(); 3442 #endif 3443 Dependencies::print_statistics(); 3444 if (xtty != NULL) xtty->tail("statistics"); 3445 } 3446 3447 #endif // !PRODUCT 3448 3449 #if INCLUDE_JVMCI 3450 void nmethod::clear_jvmci_installed_code() { 3451 // write_ref_method_pre/post can only be safely called at a 3452 // safepoint or while holding the CodeCache_lock 3453 assert(CodeCache_lock->is_locked() || 3454 SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency"); 3455 if (_jvmci_installed_code != NULL) { 3456 // This must be done carefully to maintain nmethod remembered sets properly 3457 BarrierSet* bs = Universe::heap()->barrier_set(); 3458 bs->write_ref_nmethod_pre(&_jvmci_installed_code, this); 3459 _jvmci_installed_code = NULL; 3460 bs->write_ref_nmethod_post(&_jvmci_installed_code, this); 3461 } 3462 } 3463 3464 void nmethod::maybe_invalidate_installed_code() { 3465 assert(Patching_lock->is_locked() || 3466 SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency"); 3467 oop installed_code = jvmci_installed_code(); 3468 if (installed_code != NULL) { 3469 nmethod* nm = (nmethod*)InstalledCode::address(installed_code); 3470 if (nm == NULL || nm != this) { 3471 // The link has been broken or the InstalledCode instance is 3472 // associated with another nmethod so do nothing. 3473 return; 3474 } 3475 if (!is_alive()) { 3476 // Break the link between nmethod and InstalledCode such that the nmethod 3477 // can subsequently be flushed safely. The link must be maintained while 3478 // the method could have live activations since invalidateInstalledCode 3479 // might want to invalidate all existing activations. 3480 InstalledCode::set_address(installed_code, 0); 3481 InstalledCode::set_entryPoint(installed_code, 0); 3482 } else if (is_not_entrant()) { 3483 // Remove the entry point so any invocation will fail but keep 3484 // the address link around that so that existing activations can 3485 // be invalidated. 3486 InstalledCode::set_entryPoint(installed_code, 0); 3487 } 3488 } 3489 } 3490 3491 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) { 3492 if (installedCode() == NULL) { 3493 THROW(vmSymbols::java_lang_NullPointerException()); 3494 } 3495 jlong nativeMethod = InstalledCode::address(installedCode); 3496 nmethod* nm = (nmethod*)nativeMethod; 3497 if (nm == NULL) { 3498 // Nothing to do 3499 return; 3500 } 3501 3502 nmethodLocker nml(nm); 3503 #ifdef ASSERT 3504 { 3505 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 3506 // This relationship can only be checked safely under a lock 3507 assert(nm == NULL || !nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check"); 3508 } 3509 #endif 3510 3511 if (nm->is_alive()) { 3512 // The nmethod state machinery maintains the link between the 3513 // HotSpotInstalledCode and nmethod* so as long as the nmethod appears to be 3514 // alive assume there is work to do and deoptimize the nmethod. 3515 nm->mark_for_deoptimization(); 3516 VM_Deoptimize op; 3517 VMThread::execute(&op); 3518 } 3519 3520 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 3521 // Check that it's still associated with the same nmethod and break 3522 // the link if it is. 3523 if (InstalledCode::address(installedCode) == nativeMethod) { 3524 InstalledCode::set_address(installedCode, 0); 3525 } 3526 } 3527 3528 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) { 3529 if (!this->is_compiled_by_jvmci()) { 3530 return NULL; 3531 } 3532 oop installedCode = this->jvmci_installed_code(); 3533 if (installedCode != NULL) { 3534 oop installedCodeName = NULL; 3535 if (installedCode->is_a(InstalledCode::klass())) { 3536 installedCodeName = InstalledCode::name(installedCode); 3537 } 3538 if (installedCodeName != NULL) { 3539 return java_lang_String::as_utf8_string(installedCodeName, buf, (int)buflen); 3540 } else { 3541 jio_snprintf(buf, buflen, "null"); 3542 return buf; 3543 } 3544 } 3545 jio_snprintf(buf, buflen, "noInstalledCode"); 3546 return buf; 3547 } 3548 #endif 3549 3550 Method* nmethod::attached_method(address call_instr) { 3551 assert(code_contains(call_instr), "not part of the nmethod"); 3552 RelocIterator iter(this, call_instr, call_instr + 1); 3553 while (iter.next()) { 3554 if (iter.addr() == call_instr) { 3555 switch(iter.type()) { 3556 case relocInfo::static_call_type: return iter.static_call_reloc()->method_value(); 3557 case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value(); 3558 case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value(); 3559 } 3560 } 3561 } 3562 return NULL; // not found 3563 } 3564 3565 Method* nmethod::attached_method_before_pc(address pc) { 3566 if (NativeCall::is_call_before(pc)) { 3567 NativeCall* ncall = nativeCall_before(pc); 3568 return attached_method(ncall->instruction_address()); 3569 } 3570 return NULL; // not a call 3571 } 3572