1 /* 2 * Copyright (c) 1997, 2017, 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 #ifndef SHARE_VM_CODE_NMETHOD_HPP 26 #define SHARE_VM_CODE_NMETHOD_HPP 27 28 #include "code/compiledMethod.hpp" 29 30 class DepChange; 31 class DirectiveSet; 32 33 // nmethods (native methods) are the compiled code versions of Java methods. 34 // 35 // An nmethod contains: 36 // - header (the nmethod structure) 37 // [Relocation] 38 // - relocation information 39 // - constant part (doubles, longs and floats used in nmethod) 40 // - oop table 41 // [Code] 42 // - code body 43 // - exception handler 44 // - stub code 45 // [Debugging information] 46 // - oop array 47 // - data array 48 // - pcs 49 // [Exception handler table] 50 // - handler entry point array 51 // [Implicit Null Pointer exception table] 52 // - implicit null table array 53 54 class nmethod : public CompiledMethod { 55 friend class VMStructs; 56 friend class JVMCIVMStructs; 57 friend class NMethodSweeper; 58 friend class CodeCache; // scavengable oops 59 private: 60 61 // Shared fields for all nmethod's 62 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method 63 jmethodID _jmethod_id; // Cache of method()->jmethod_id() 64 65 #if INCLUDE_JVMCI 66 // A weak reference to an InstalledCode object associated with 67 // this nmethod. 68 jweak _jvmci_installed_code; 69 70 // A weak reference to a SpeculationLog object associated with 71 // this nmethod. 72 jweak _speculation_log; 73 74 // Determines whether this nmethod is unloaded when the 75 // referent in _jvmci_installed_code is cleared. This 76 // will be false if the referent is initialized to a 77 // HotSpotNMethod object whose isDefault field is true. 78 // That is, installed code other than a "default" 79 // HotSpotNMethod causes nmethod unloading. 80 // This field is ignored once _jvmci_installed_code is NULL. 81 bool _jvmci_installed_code_triggers_unloading; 82 #endif 83 84 // To support simple linked-list chaining of nmethods: 85 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head 86 87 static nmethod* volatile _oops_do_mark_nmethods; 88 nmethod* volatile _oops_do_mark_link; 89 90 // offsets for entry points 91 address _entry_point; // entry point with class check 92 address _verified_entry_point; // entry point without class check 93 address _osr_entry_point; // entry point for on stack replacement 94 95 // Offsets for different nmethod parts 96 int _exception_offset; 97 // Offset of the unwind handler if it exists 98 int _unwind_handler_offset; 99 100 int _consts_offset; 101 int _stub_offset; 102 int _oops_offset; // offset to where embedded oop table begins (inside data) 103 int _metadata_offset; // embedded meta data table 104 int _scopes_data_offset; 105 int _scopes_pcs_offset; 106 int _dependencies_offset; 107 int _handler_table_offset; 108 int _nul_chk_table_offset; 109 int _nmethod_end_offset; 110 111 int code_offset() const { return (address) code_begin() - header_begin(); } 112 113 // location in frame (offset for sp) that deopt can store the original 114 // pc during a deopt. 115 int _orig_pc_offset; 116 117 int _compile_id; // which compilation made this nmethod 118 int _comp_level; // compilation level 119 120 // protected by CodeCache_lock 121 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock) 122 123 // used by jvmti to track if an unload event has been posted for this nmethod. 124 bool _unload_reported; 125 126 // Protected by Patching_lock 127 volatile unsigned char _state; // {in_use, not_entrant, zombie, unloaded} 128 129 #ifdef ASSERT 130 bool _oops_are_stale; // indicates that it's no longer safe to access oops section 131 #endif 132 133 jbyte _scavenge_root_state; 134 135 #if INCLUDE_RTM_OPT 136 // RTM state at compile time. Used during deoptimization to decide 137 // whether to restart collecting RTM locking abort statistic again. 138 RTMState _rtm_state; 139 #endif 140 141 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed 142 // and is not made into a zombie. However, once the nmethod is made into 143 // a zombie, it will be locked one final time if CompiledMethodUnload 144 // event processing needs to be done. 145 volatile jint _lock_count; 146 147 // not_entrant method removal. Each mark_sweep pass will update 148 // this mark to current sweep invocation count if it is seen on the 149 // stack. An not_entrant method can be removed when there are no 150 // more activations, i.e., when the _stack_traversal_mark is less than 151 // current sweep traversal index. 152 volatile long _stack_traversal_mark; 153 154 // The _hotness_counter indicates the hotness of a method. The higher 155 // the value the hotter the method. The hotness counter of a nmethod is 156 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method 157 // is active while stack scanning (mark_active_nmethods()). The hotness 158 // counter is decreased (by 1) while sweeping. 159 int _hotness_counter; 160 161 // These are used for compiled synchronized native methods to 162 // locate the owner and stack slot for the BasicLock so that we can 163 // properly revoke the bias of the owner if necessary. They are 164 // needed because there is no debug information for compiled native 165 // wrappers and the oop maps are insufficient to allow 166 // frame::retrieve_receiver() to work. Currently they are expected 167 // to be byte offsets from the Java stack pointer for maximum code 168 // sharing between platforms. Note that currently biased locking 169 // will never cause Class instances to be biased but this code 170 // handles the static synchronized case as well. 171 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver 172 // for non-static native wrapper frames. 173 ByteSize _native_receiver_sp_offset; 174 ByteSize _native_basic_lock_sp_offset; 175 176 friend class nmethodLocker; 177 178 // For native wrappers 179 nmethod(Method* method, 180 CompilerType type, 181 int nmethod_size, 182 int compile_id, 183 CodeOffsets* offsets, 184 CodeBuffer *code_buffer, 185 int frame_size, 186 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */ 187 ByteSize basic_lock_sp_offset, /* synchronized natives only */ 188 OopMapSet* oop_maps); 189 190 // Creation support 191 nmethod(Method* method, 192 CompilerType type, 193 int nmethod_size, 194 int compile_id, 195 int entry_bci, 196 CodeOffsets* offsets, 197 int orig_pc_offset, 198 DebugInformationRecorder *recorder, 199 Dependencies* dependencies, 200 CodeBuffer *code_buffer, 201 int frame_size, 202 OopMapSet* oop_maps, 203 ExceptionHandlerTable* handler_table, 204 ImplicitExceptionTable* nul_chk_table, 205 AbstractCompiler* compiler, 206 int comp_level 207 #if INCLUDE_JVMCI 208 , jweak installed_code, 209 jweak speculation_log 210 #endif 211 ); 212 213 // helper methods 214 void* operator new(size_t size, int nmethod_size, int comp_level) throw(); 215 216 const char* reloc_string_for(u_char* begin, u_char* end); 217 // Returns true if this thread changed the state of the nmethod or 218 // false if another thread performed the transition. 219 bool make_not_entrant_or_zombie(unsigned int state); 220 bool make_entrant() { Unimplemented(); return false; } 221 void inc_decompile_count(); 222 223 // Inform external interfaces that a compiled method has been unloaded 224 void post_compiled_method_unload(); 225 226 // Initailize fields to their default values 227 void init_defaults(); 228 229 // Offsets 230 int content_offset() const { return content_begin() - header_begin(); } 231 int data_offset() const { return _data_offset; } 232 233 address header_end() const { return (address) header_begin() + header_size(); } 234 235 public: 236 // create nmethod with entry_bci 237 static nmethod* new_nmethod(const methodHandle& method, 238 int compile_id, 239 int entry_bci, 240 CodeOffsets* offsets, 241 int orig_pc_offset, 242 DebugInformationRecorder* recorder, 243 Dependencies* dependencies, 244 CodeBuffer *code_buffer, 245 int frame_size, 246 OopMapSet* oop_maps, 247 ExceptionHandlerTable* handler_table, 248 ImplicitExceptionTable* nul_chk_table, 249 AbstractCompiler* compiler, 250 int comp_level 251 #if INCLUDE_JVMCI 252 , jweak installed_code = NULL, 253 jweak speculation_log = NULL 254 #endif 255 ); 256 257 static nmethod* new_native_nmethod(const methodHandle& method, 258 int compile_id, 259 CodeBuffer *code_buffer, 260 int vep_offset, 261 int frame_complete, 262 int frame_size, 263 ByteSize receiver_sp_offset, 264 ByteSize basic_lock_sp_offset, 265 OopMapSet* oop_maps); 266 267 // type info 268 bool is_nmethod() const { return true; } 269 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; } 270 271 // boundaries for different parts 272 address consts_begin () const { return header_begin() + _consts_offset ; } 273 address consts_end () const { return code_begin() ; } 274 address stub_begin () const { return header_begin() + _stub_offset ; } 275 address stub_end () const { return header_begin() + _oops_offset ; } 276 address exception_begin () const { return header_begin() + _exception_offset ; } 277 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; } 278 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; } 279 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; } 280 281 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; } 282 Metadata** metadata_end () const { return (Metadata**) _scopes_data_begin; } 283 284 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; } 285 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); } 286 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; } 287 address dependencies_begin () const { return header_begin() + _dependencies_offset ; } 288 address dependencies_end () const { return header_begin() + _handler_table_offset ; } 289 address handler_table_begin () const { return header_begin() + _handler_table_offset ; } 290 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; } 291 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; } 292 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; } 293 294 // Sizes 295 int oops_size () const { return (address) oops_end () - (address) oops_begin (); } 296 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); } 297 int dependencies_size () const { return dependencies_end () - dependencies_begin (); } 298 299 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; } 300 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; } 301 302 int total_size () const; 303 304 void dec_hotness_counter() { _hotness_counter--; } 305 void set_hotness_counter(int val) { _hotness_counter = val; } 306 int hotness_counter() const { return _hotness_counter; } 307 308 // Containment 309 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); } 310 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); } 311 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); } 312 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); } 313 314 // entry points 315 address entry_point() const { return _entry_point; } // normal entry point 316 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct 317 318 // flag accessing and manipulation 319 bool is_in_use() const { return _state == in_use; } 320 bool is_alive() const { unsigned char s = _state; return s < zombie; } 321 bool is_not_entrant() const { return _state == not_entrant; } 322 bool is_zombie() const { return _state == zombie; } 323 bool is_unloaded() const { return _state == unloaded; } 324 325 #if INCLUDE_RTM_OPT 326 // rtm state accessing and manipulating 327 RTMState rtm_state() const { return _rtm_state; } 328 void set_rtm_state(RTMState state) { _rtm_state = state; } 329 #endif 330 331 // Make the nmethod non entrant. The nmethod will continue to be 332 // alive. It is used when an uncommon trap happens. Returns true 333 // if this thread changed the state of the nmethod or false if 334 // another thread performed the transition. 335 bool make_not_entrant() { 336 assert(!method()->is_method_handle_intrinsic(), "Cannot make MH intrinsic not entrant"); 337 return make_not_entrant_or_zombie(not_entrant); 338 } 339 bool make_not_used() { return make_not_entrant(); } 340 bool make_zombie() { return make_not_entrant_or_zombie(zombie); } 341 342 // used by jvmti to track if the unload event has been reported 343 bool unload_reported() { return _unload_reported; } 344 void set_unload_reported() { _unload_reported = true; } 345 346 int get_state() const { 347 return _state; 348 } 349 350 void make_unloaded(BoolObjectClosure* is_alive, oop cause); 351 352 bool has_dependencies() { return dependencies_size() != 0; } 353 void flush_dependencies(BoolObjectClosure* is_alive); 354 bool has_flushed_dependencies() { return _has_flushed_dependencies; } 355 void set_has_flushed_dependencies() { 356 assert(!has_flushed_dependencies(), "should only happen once"); 357 _has_flushed_dependencies = 1; 358 } 359 360 int comp_level() const { return _comp_level; } 361 362 // Support for oops in scopes and relocs: 363 // Note: index 0 is reserved for null. 364 oop oop_at(int index) const { return index == 0 ? (oop) NULL: *oop_addr_at(index); } 365 oop* oop_addr_at(int index) const { // for GC 366 // relocation indexes are biased by 1 (because 0 is reserved) 367 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index"); 368 assert(!_oops_are_stale, "oops are stale"); 369 return &oops_begin()[index - 1]; 370 } 371 372 // Support for meta data in scopes and relocs: 373 // Note: index 0 is reserved for null. 374 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); } 375 Metadata** metadata_addr_at(int index) const { // for GC 376 // relocation indexes are biased by 1 (because 0 is reserved) 377 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index"); 378 return &metadata_begin()[index - 1]; 379 } 380 381 void copy_values(GrowableArray<jobject>* oops); 382 void copy_values(GrowableArray<Metadata*>* metadata); 383 384 // Relocation support 385 private: 386 void fix_oop_relocations(address begin, address end, bool initialize_immediates); 387 inline void initialize_immediate_oop(oop* dest, jobject handle); 388 389 public: 390 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); } 391 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); } 392 393 // Scavengable oop support 394 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; } 395 protected: 396 enum { sl_on_list = 0x01, sl_marked = 0x10 }; 397 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; } 398 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; } 399 // assertion-checking and pruning logic uses the bits of _scavenge_root_state 400 #ifndef PRODUCT 401 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; } 402 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; } 403 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; } 404 // N.B. there is no positive marked query, and we only use the not_marked query for asserts. 405 #endif //PRODUCT 406 nmethod* scavenge_root_link() const { return _scavenge_root_link; } 407 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; } 408 409 public: 410 411 // Sweeper support 412 long stack_traversal_mark() { return _stack_traversal_mark; } 413 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; } 414 415 // implicit exceptions support 416 address continuation_for_implicit_exception(address pc); 417 418 // On-stack replacement support 419 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; } 420 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; } 421 void invalidate_osr_method(); 422 nmethod* osr_link() const { return _osr_link; } 423 void set_osr_link(nmethod *n) { _osr_link = n; } 424 425 // Verify calls to dead methods have been cleaned. 426 void verify_clean_inline_caches(); 427 428 // unlink and deallocate this nmethod 429 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not 430 // expected to use any other private methods/data in this class. 431 432 protected: 433 void flush(); 434 435 public: 436 // When true is returned, it is unsafe to remove this nmethod even if 437 // it is a zombie, since the VM or the ServiceThread might still be 438 // using it. 439 bool is_locked_by_vm() const { return _lock_count >0; } 440 441 // See comment at definition of _last_seen_on_stack 442 void mark_as_seen_on_stack(); 443 bool can_convert_to_zombie(); 444 445 // Evolution support. We make old (discarded) compiled methods point to new Method*s. 446 void set_method(Method* method) { _method = method; } 447 448 #if INCLUDE_JVMCI 449 // Gets the InstalledCode object associated with this nmethod 450 // which may be NULL if this nmethod was not compiled by JVMCI 451 // or the weak reference has been cleared. 452 oop jvmci_installed_code(); 453 454 // Copies the value of the name field in the InstalledCode 455 // object (if any) associated with this nmethod into buf. 456 // Returns the value of buf if it was updated otherwise NULL. 457 char* jvmci_installed_code_name(char* buf, size_t buflen); 458 459 // Updates the state of the InstalledCode (if any) associated with 460 // this nmethod based on the current value of _state. 461 void maybe_invalidate_installed_code(); 462 463 // Deoptimizes the nmethod (if any) in the address field of a given 464 // InstalledCode object. The address field is zeroed upon return. 465 static void invalidate_installed_code(Handle installed_code, TRAPS); 466 467 // Gets the SpeculationLog object associated with this nmethod 468 // which may be NULL if this nmethod was not compiled by JVMCI 469 // or the weak reference has been cleared. 470 oop speculation_log(); 471 472 private: 473 // Deletes the weak reference (if any) to the InstalledCode object 474 // associated with this nmethod. 475 void clear_jvmci_installed_code(); 476 477 // Deletes the weak reference (if any) to the SpeculationLog object 478 // associated with this nmethod. 479 void clear_speculation_log(); 480 481 public: 482 #endif 483 484 protected: 485 virtual bool do_unloading_oops(address low_boundary, BoolObjectClosure* is_alive, bool unloading_occurred); 486 #if INCLUDE_JVMCI 487 // See comment for _jvmci_installed_code_triggers_unloading field. 488 // Returns whether this nmethod was unloaded. 489 virtual bool do_unloading_jvmci(BoolObjectClosure* is_alive, bool unloading_occurred); 490 #endif 491 492 private: 493 bool do_unloading_scopes(BoolObjectClosure* is_alive, bool unloading_occurred); 494 // Unload a nmethod if the *root object is dead. 495 bool can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred); 496 bool unload_if_dead_at(RelocIterator *iter_at_oop, BoolObjectClosure* is_alive, bool unloading_occurred); 497 498 public: 499 void oops_do(OopClosure* f) { oops_do(f, false); } 500 void oops_do(OopClosure* f, bool allow_zombie); 501 bool detect_scavenge_root_oops(); 502 void verify_scavenge_root_oops() PRODUCT_RETURN; 503 504 bool test_set_oops_do_mark(); 505 static void oops_do_marking_prologue(); 506 static void oops_do_marking_epilogue(); 507 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; } 508 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; } 509 510 private: 511 ScopeDesc* scope_desc_in(address begin, address end); 512 513 address* orig_pc_addr(const frame* fr) { return (address*) ((address)fr->unextended_sp() + _orig_pc_offset); } 514 515 public: 516 // copying of debugging information 517 void copy_scopes_pcs(PcDesc* pcs, int count); 518 void copy_scopes_data(address buffer, int size); 519 520 // Accessor/mutator for the original pc of a frame before a frame was deopted. 521 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); } 522 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; } 523 524 // jvmti support: 525 void post_compiled_method_load_event(); 526 jmethodID get_and_cache_jmethod_id(); 527 528 // verify operations 529 void verify(); 530 void verify_scopes(); 531 void verify_interrupt_point(address interrupt_point); 532 533 // printing support 534 void print() const; 535 void print_relocations() PRODUCT_RETURN; 536 void print_pcs() PRODUCT_RETURN; 537 void print_scopes() PRODUCT_RETURN; 538 void print_dependencies() PRODUCT_RETURN; 539 void print_value_on(outputStream* st) const PRODUCT_RETURN; 540 void print_calls(outputStream* st) PRODUCT_RETURN; 541 void print_handler_table() PRODUCT_RETURN; 542 void print_nul_chk_table() PRODUCT_RETURN; 543 void print_recorded_oops() PRODUCT_RETURN; 544 void print_recorded_metadata() PRODUCT_RETURN; 545 546 void maybe_print_nmethod(DirectiveSet* directive); 547 void print_nmethod(bool print_code); 548 549 // need to re-define this from CodeBlob else the overload hides it 550 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); } 551 void print_on(outputStream* st, const char* msg) const; 552 553 // Logging 554 void log_identity(xmlStream* log) const; 555 void log_new_nmethod() const; 556 void log_state_change() const; 557 558 // Prints block-level comments, including nmethod specific block labels: 559 virtual void print_block_comment(outputStream* stream, address block_begin) const { 560 print_nmethod_labels(stream, block_begin); 561 CodeBlob::print_block_comment(stream, block_begin); 562 } 563 void print_nmethod_labels(outputStream* stream, address block_begin) const; 564 565 // Prints a comment for one native instruction (reloc info, pc desc) 566 void print_code_comment_on(outputStream* st, int column, address begin, address end); 567 static void print_statistics() PRODUCT_RETURN; 568 569 // Compiler task identification. Note that all OSR methods 570 // are numbered in an independent sequence if CICountOSR is true, 571 // and native method wrappers are also numbered independently if 572 // CICountNative is true. 573 virtual int compile_id() const { return _compile_id; } 574 const char* compile_kind() const; 575 576 // tells if any of this method's dependencies have been invalidated 577 // (this is expensive!) 578 static void check_all_dependencies(DepChange& changes); 579 580 // tells if this compiled method is dependent on the given changes, 581 // and the changes have invalidated it 582 bool check_dependency_on(DepChange& changes); 583 584 // Evolution support. Tells if this compiled method is dependent on any of 585 // methods m() of class dependee, such that if m() in dependee is replaced, 586 // this compiled method will have to be deoptimized. 587 bool is_evol_dependent_on(Klass* dependee); 588 589 // Fast breakpoint support. Tells if this compiled method is 590 // dependent on the given method. Returns true if this nmethod 591 // corresponds to the given method as well. 592 virtual bool is_dependent_on_method(Method* dependee); 593 594 // is it ok to patch at address? 595 bool is_patchable_at(address instr_address); 596 597 // UseBiasedLocking support 598 ByteSize native_receiver_sp_offset() { 599 return _native_receiver_sp_offset; 600 } 601 ByteSize native_basic_lock_sp_offset() { 602 return _native_basic_lock_sp_offset; 603 } 604 605 // support for code generation 606 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); } 607 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); } 608 static int state_offset() { return offset_of(nmethod, _state); } 609 610 virtual void metadata_do(void f(Metadata*)); 611 612 NativeCallWrapper* call_wrapper_at(address call) const; 613 NativeCallWrapper* call_wrapper_before(address return_pc) const; 614 address call_instruction_address(address pc) const; 615 616 virtual CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) const; 617 virtual CompiledStaticCall* compiledStaticCall_at(address addr) const; 618 virtual CompiledStaticCall* compiledStaticCall_before(address addr) const; 619 }; 620 621 // Locks an nmethod so its code will not get removed and it will not 622 // be made into a zombie, even if it is a not_entrant method. After the 623 // nmethod becomes a zombie, if CompiledMethodUnload event processing 624 // needs to be done, then lock_nmethod() is used directly to keep the 625 // generated code from being reused too early. 626 class nmethodLocker : public StackObj { 627 CompiledMethod* _nm; 628 629 public: 630 631 // note: nm can be NULL 632 // Only JvmtiDeferredEvent::compiled_method_unload_event() 633 // should pass zombie_ok == true. 634 static void lock_nmethod(CompiledMethod* nm, bool zombie_ok = false); 635 static void unlock_nmethod(CompiledMethod* nm); // (ditto) 636 637 nmethodLocker(address pc); // derive nm from pc 638 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); } 639 nmethodLocker(CompiledMethod *nm) { 640 _nm = nm; 641 lock(_nm); 642 } 643 644 static void lock(CompiledMethod* method) { 645 if (method == NULL) return; 646 lock_nmethod(method); 647 } 648 649 static void unlock(CompiledMethod* method) { 650 if (method == NULL) return; 651 unlock_nmethod(method); 652 } 653 654 nmethodLocker() { _nm = NULL; } 655 ~nmethodLocker() { 656 unlock(_nm); 657 } 658 659 CompiledMethod* code() { return _nm; } 660 void set_code(CompiledMethod* new_nm) { 661 unlock(_nm); // note: This works even if _nm==new_nm. 662 _nm = new_nm; 663 lock(_nm); 664 } 665 }; 666 667 #endif // SHARE_VM_CODE_NMETHOD_HPP