1 /* 2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_CODE_NMETHOD_HPP 26 #define SHARE_VM_CODE_NMETHOD_HPP 27 28 #include "code/codeBlob.hpp" 29 #include "code/pcDesc.hpp" 30 #include "oops/metadata.hpp" 31 32 // This class is used internally by nmethods, to cache 33 // exception/pc/handler information. 34 35 class ExceptionCache : public CHeapObj<mtCode> { 36 friend class VMStructs; 37 private: 38 enum { cache_size = 16 }; 39 Klass* _exception_type; 40 address _pc[cache_size]; 41 address _handler[cache_size]; 42 int _count; 43 ExceptionCache* _next; 44 45 address pc_at(int index) { assert(index >= 0 && index < count(),""); return _pc[index]; } 46 void set_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; } 47 address handler_at(int index) { assert(index >= 0 && index < count(),""); return _handler[index]; } 48 void set_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; } 49 int count() { return _count; } 50 void increment_count() { _count++; } 51 52 public: 53 54 ExceptionCache(Handle exception, address pc, address handler); 55 56 Klass* exception_type() { return _exception_type; } 57 ExceptionCache* next() { return _next; } 58 void set_next(ExceptionCache *ec) { _next = ec; } 59 60 address match(Handle exception, address pc); 61 bool match_exception_with_space(Handle exception) ; 62 address test_address(address addr); 63 bool add_address_and_handler(address addr, address handler) ; 64 }; 65 66 67 // cache pc descs found in earlier inquiries 68 class PcDescCache VALUE_OBJ_CLASS_SPEC { 69 friend class VMStructs; 70 private: 71 enum { cache_size = 4 }; 72 // The array elements MUST be volatile! Several threads may modify 73 // and read from the cache concurrently. find_pc_desc_internal has 74 // returned wrong results. C++ compiler (namely xlC12) may duplicate 75 // C++ field accesses if the elements are not volatile. 76 typedef PcDesc* PcDescPtr; 77 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found 78 public: 79 PcDescCache() { debug_only(_pc_descs[0] = NULL); } 80 void reset_to(PcDesc* initial_pc_desc); 81 PcDesc* find_pc_desc(int pc_offset, bool approximate); 82 void add_pc_desc(PcDesc* pc_desc); 83 PcDesc* last_pc_desc() { return _pc_descs[0]; } 84 }; 85 86 87 // nmethods (native methods) are the compiled code versions of Java methods. 88 // 89 // An nmethod contains: 90 // - header (the nmethod structure) 91 // [Relocation] 92 // - relocation information 93 // - constant part (doubles, longs and floats used in nmethod) 94 // - oop table 95 // [Code] 96 // - code body 97 // - exception handler 98 // - stub code 99 // [Debugging information] 100 // - oop array 101 // - data array 102 // - pcs 103 // [Exception handler table] 104 // - handler entry point array 105 // [Implicit Null Pointer exception table] 106 // - implicit null table array 107 108 class Dependencies; 109 class ExceptionHandlerTable; 110 class ImplicitExceptionTable; 111 class AbstractCompiler; 112 class xmlStream; 113 114 class nmethod : public CodeBlob { 115 friend class VMStructs; 116 friend class NMethodSweeper; 117 friend class CodeCache; // scavengable oops 118 private: 119 120 // GC support to help figure out if an nmethod has been 121 // cleaned/unloaded by the current GC. 122 static unsigned char _global_unloading_clock; 123 124 // Shared fields for all nmethod's 125 Method* _method; 126 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method 127 jmethodID _jmethod_id; // Cache of method()->jmethod_id() 128 129 // To support simple linked-list chaining of nmethods: 130 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head 131 132 union { 133 // Used by G1 to chain nmethods. 134 nmethod* _unloading_next; 135 // Used by non-G1 GCs to chain nmethods. 136 nmethod* _scavenge_root_link; // from CodeCache::scavenge_root_nmethods 137 }; 138 139 static nmethod* volatile _oops_do_mark_nmethods; 140 nmethod* volatile _oops_do_mark_link; 141 142 AbstractCompiler* _compiler; // The compiler which compiled this nmethod 143 144 // offsets for entry points 145 address _entry_point; // entry point with class check 146 address _verified_entry_point; // entry point without class check 147 address _osr_entry_point; // entry point for on stack replacement 148 149 // Offsets for different nmethod parts 150 int _exception_offset; 151 // All deoptee's will resume execution at this location described by 152 // this offset. 153 int _deoptimize_offset; 154 // All deoptee's at a MethodHandle call site will resume execution 155 // at this location described by this offset. 156 int _deoptimize_mh_offset; 157 // Offset of the unwind handler if it exists 158 int _unwind_handler_offset; 159 160 #ifdef HAVE_DTRACE_H 161 int _trap_offset; 162 #endif // def HAVE_DTRACE_H 163 int _consts_offset; 164 int _stub_offset; 165 int _oops_offset; // offset to where embedded oop table begins (inside data) 166 int _metadata_offset; // embedded meta data table 167 int _scopes_data_offset; 168 int _scopes_pcs_offset; 169 int _dependencies_offset; 170 int _handler_table_offset; 171 int _nul_chk_table_offset; 172 int _nmethod_end_offset; 173 174 // location in frame (offset for sp) that deopt can store the original 175 // pc during a deopt. 176 int _orig_pc_offset; 177 178 int _compile_id; // which compilation made this nmethod 179 int _comp_level; // compilation level 180 181 // protected by CodeCache_lock 182 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock) 183 184 bool _marked_for_reclamation; // Used by NMethodSweeper (set only by sweeper) 185 bool _marked_for_deoptimization; // Used for stack deoptimization 186 187 // used by jvmti to track if an unload event has been posted for this nmethod. 188 bool _unload_reported; 189 190 // set during construction 191 unsigned int _has_unsafe_access:1; // May fault due to unsafe access. 192 unsigned int _has_method_handle_invokes:1; // Has this method MethodHandle invokes? 193 unsigned int _lazy_critical_native:1; // Lazy JNI critical native 194 unsigned int _has_wide_vectors:1; // Preserve wide vectors at safepoints 195 196 // Protected by Patching_lock 197 volatile unsigned char _state; // {alive, not_entrant, zombie, unloaded} 198 199 volatile unsigned char _unloading_clock; // Incremented after GC unloaded/cleaned the nmethod 200 201 #ifdef ASSERT 202 bool _oops_are_stale; // indicates that it's no longer safe to access oops section 203 #endif 204 205 enum { in_use = 0, // executable nmethod 206 not_entrant = 1, // marked for deoptimization but activations may still exist, 207 // will be transformed to zombie when all activations are gone 208 zombie = 2, // no activations exist, nmethod is ready for purge 209 unloaded = 3 }; // there should be no activations, should not be called, 210 // will be transformed to zombie immediately 211 212 jbyte _scavenge_root_state; 213 214 #if INCLUDE_RTM_OPT 215 // RTM state at compile time. Used during deoptimization to decide 216 // whether to restart collecting RTM locking abort statistic again. 217 RTMState _rtm_state; 218 #endif 219 220 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed 221 // and is not made into a zombie. However, once the nmethod is made into 222 // a zombie, it will be locked one final time if CompiledMethodUnload 223 // event processing needs to be done. 224 volatile jint _lock_count; 225 226 // not_entrant method removal. Each mark_sweep pass will update 227 // this mark to current sweep invocation count if it is seen on the 228 // stack. An not_entrant method can be removed when there are no 229 // more activations, i.e., when the _stack_traversal_mark is less than 230 // current sweep traversal index. 231 long _stack_traversal_mark; 232 233 // The _hotness_counter indicates the hotness of a method. The higher 234 // the value the hotter the method. The hotness counter of a nmethod is 235 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method 236 // is active while stack scanning (mark_active_nmethods()). The hotness 237 // counter is decreased (by 1) while sweeping. 238 int _hotness_counter; 239 240 ExceptionCache *_exception_cache; 241 PcDescCache _pc_desc_cache; 242 243 // These are used for compiled synchronized native methods to 244 // locate the owner and stack slot for the BasicLock so that we can 245 // properly revoke the bias of the owner if necessary. They are 246 // needed because there is no debug information for compiled native 247 // wrappers and the oop maps are insufficient to allow 248 // frame::retrieve_receiver() to work. Currently they are expected 249 // to be byte offsets from the Java stack pointer for maximum code 250 // sharing between platforms. Note that currently biased locking 251 // will never cause Class instances to be biased but this code 252 // handles the static synchronized case as well. 253 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver 254 // for non-static native wrapper frames. 255 ByteSize _native_receiver_sp_offset; 256 ByteSize _native_basic_lock_sp_offset; 257 258 friend class nmethodLocker; 259 260 // For native wrappers 261 nmethod(Method* method, 262 int nmethod_size, 263 int compile_id, 264 CodeOffsets* offsets, 265 CodeBuffer *code_buffer, 266 int frame_size, 267 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */ 268 ByteSize basic_lock_sp_offset, /* synchronized natives only */ 269 OopMapSet* oop_maps); 270 271 #ifdef HAVE_DTRACE_H 272 // For native wrappers 273 nmethod(Method* method, 274 int nmethod_size, 275 CodeOffsets* offsets, 276 CodeBuffer *code_buffer, 277 int frame_size); 278 #endif // def HAVE_DTRACE_H 279 280 // Creation support 281 nmethod(Method* method, 282 int nmethod_size, 283 int compile_id, 284 int entry_bci, 285 CodeOffsets* offsets, 286 int orig_pc_offset, 287 DebugInformationRecorder *recorder, 288 Dependencies* dependencies, 289 CodeBuffer *code_buffer, 290 int frame_size, 291 OopMapSet* oop_maps, 292 ExceptionHandlerTable* handler_table, 293 ImplicitExceptionTable* nul_chk_table, 294 AbstractCompiler* compiler, 295 int comp_level); 296 297 // helper methods 298 void* operator new(size_t size, int nmethod_size) throw(); 299 300 const char* reloc_string_for(u_char* begin, u_char* end); 301 // Returns true if this thread changed the state of the nmethod or 302 // false if another thread performed the transition. 303 bool make_not_entrant_or_zombie(unsigned int state); 304 void inc_decompile_count(); 305 306 // Used to manipulate the exception cache 307 void add_exception_cache_entry(ExceptionCache* new_entry); 308 ExceptionCache* exception_cache_entry_for_exception(Handle exception); 309 310 // Inform external interfaces that a compiled method has been unloaded 311 void post_compiled_method_unload(); 312 313 // Initailize fields to their default values 314 void init_defaults(); 315 316 public: 317 // create nmethod with entry_bci 318 static nmethod* new_nmethod(methodHandle method, 319 int compile_id, 320 int entry_bci, 321 CodeOffsets* offsets, 322 int orig_pc_offset, 323 DebugInformationRecorder* recorder, 324 Dependencies* dependencies, 325 CodeBuffer *code_buffer, 326 int frame_size, 327 OopMapSet* oop_maps, 328 ExceptionHandlerTable* handler_table, 329 ImplicitExceptionTable* nul_chk_table, 330 AbstractCompiler* compiler, 331 int comp_level); 332 333 static nmethod* new_native_nmethod(methodHandle method, 334 int compile_id, 335 CodeBuffer *code_buffer, 336 int vep_offset, 337 int frame_complete, 338 int frame_size, 339 ByteSize receiver_sp_offset, 340 ByteSize basic_lock_sp_offset, 341 OopMapSet* oop_maps); 342 343 #ifdef HAVE_DTRACE_H 344 // The method we generate for a dtrace probe has to look 345 // like an nmethod as far as the rest of the system is concerned 346 // which is somewhat unfortunate. 347 static nmethod* new_dtrace_nmethod(methodHandle method, 348 CodeBuffer *code_buffer, 349 int vep_offset, 350 int trap_offset, 351 int frame_complete, 352 int frame_size); 353 354 int trap_offset() const { return _trap_offset; } 355 address trap_address() const { return insts_begin() + _trap_offset; } 356 357 #endif // def HAVE_DTRACE_H 358 359 // accessors 360 Method* method() const { return _method; } 361 AbstractCompiler* compiler() const { return _compiler; } 362 363 // type info 364 bool is_nmethod() const { return true; } 365 bool is_java_method() const { return !method()->is_native(); } 366 bool is_native_method() const { return method()->is_native(); } 367 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; } 368 369 bool is_compiled_by_c1() const; 370 bool is_compiled_by_c2() const; 371 bool is_compiled_by_shark() const; 372 373 // boundaries for different parts 374 address consts_begin () const { return header_begin() + _consts_offset ; } 375 address consts_end () const { return header_begin() + code_offset() ; } 376 address insts_begin () const { return header_begin() + code_offset() ; } 377 address insts_end () const { return header_begin() + _stub_offset ; } 378 address stub_begin () const { return header_begin() + _stub_offset ; } 379 address stub_end () const { return header_begin() + _oops_offset ; } 380 address exception_begin () const { return header_begin() + _exception_offset ; } 381 address deopt_handler_begin () const { return header_begin() + _deoptimize_offset ; } 382 address deopt_mh_handler_begin() const { return header_begin() + _deoptimize_mh_offset ; } 383 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; } 384 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; } 385 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; } 386 387 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; } 388 Metadata** metadata_end () const { return (Metadata**) (header_begin() + _scopes_data_offset) ; } 389 390 address scopes_data_begin () const { return header_begin() + _scopes_data_offset ; } 391 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; } 392 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); } 393 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; } 394 address dependencies_begin () const { return header_begin() + _dependencies_offset ; } 395 address dependencies_end () const { return header_begin() + _handler_table_offset ; } 396 address handler_table_begin () const { return header_begin() + _handler_table_offset ; } 397 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; } 398 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; } 399 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; } 400 401 // Sizes 402 int consts_size () const { return consts_end () - consts_begin (); } 403 int insts_size () const { return insts_end () - insts_begin (); } 404 int stub_size () const { return stub_end () - stub_begin (); } 405 int oops_size () const { return (address) oops_end () - (address) oops_begin (); } 406 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); } 407 int scopes_data_size () const { return scopes_data_end () - scopes_data_begin (); } 408 int scopes_pcs_size () const { return (intptr_t) scopes_pcs_end () - (intptr_t) scopes_pcs_begin (); } 409 int dependencies_size () const { return dependencies_end () - dependencies_begin (); } 410 int handler_table_size() const { return handler_table_end() - handler_table_begin(); } 411 int nul_chk_table_size() const { return nul_chk_table_end() - nul_chk_table_begin(); } 412 413 int total_size () const; 414 415 void dec_hotness_counter() { _hotness_counter--; } 416 void set_hotness_counter(int val) { _hotness_counter = val; } 417 int hotness_counter() const { return _hotness_counter; } 418 419 // Containment 420 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); } 421 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); } 422 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); } 423 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); } 424 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); } 425 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); } 426 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); } 427 bool handler_table_contains(address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); } 428 bool nul_chk_table_contains(address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); } 429 430 // entry points 431 address entry_point() const { return _entry_point; } // normal entry point 432 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct 433 434 // flag accessing and manipulation 435 bool is_in_use() const { return _state == in_use; } 436 bool is_alive() const { return _state == in_use || _state == not_entrant; } 437 bool is_not_entrant() const { return _state == not_entrant; } 438 bool is_zombie() const { return _state == zombie; } 439 bool is_unloaded() const { return _state == unloaded; } 440 441 #if INCLUDE_RTM_OPT 442 // rtm state accessing and manipulating 443 RTMState rtm_state() const { return _rtm_state; } 444 void set_rtm_state(RTMState state) { _rtm_state = state; } 445 #endif 446 447 // Make the nmethod non entrant. The nmethod will continue to be 448 // alive. It is used when an uncommon trap happens. Returns true 449 // if this thread changed the state of the nmethod or false if 450 // another thread performed the transition. 451 bool make_not_entrant() { return make_not_entrant_or_zombie(not_entrant); } 452 bool make_zombie() { return make_not_entrant_or_zombie(zombie); } 453 454 // used by jvmti to track if the unload event has been reported 455 bool unload_reported() { return _unload_reported; } 456 void set_unload_reported() { _unload_reported = true; } 457 458 void set_unloading_next(nmethod* next) { _unloading_next = next; } 459 nmethod* unloading_next() { return _unloading_next; } 460 461 static unsigned char global_unloading_clock() { return _global_unloading_clock; } 462 static void increase_unloading_clock(); 463 464 void set_unloading_clock(unsigned char unloading_clock); 465 unsigned char unloading_clock(); 466 467 bool is_marked_for_deoptimization() const { return _marked_for_deoptimization; } 468 void mark_for_deoptimization() { _marked_for_deoptimization = true; } 469 470 void make_unloaded(BoolObjectClosure* is_alive, oop cause); 471 472 bool has_dependencies() { return dependencies_size() != 0; } 473 void flush_dependencies(BoolObjectClosure* is_alive); 474 bool has_flushed_dependencies() { return _has_flushed_dependencies; } 475 void set_has_flushed_dependencies() { 476 assert(!has_flushed_dependencies(), "should only happen once"); 477 _has_flushed_dependencies = 1; 478 } 479 480 bool is_marked_for_reclamation() const { return _marked_for_reclamation; } 481 void mark_for_reclamation() { _marked_for_reclamation = 1; } 482 483 bool has_unsafe_access() const { return _has_unsafe_access; } 484 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; } 485 486 bool has_method_handle_invokes() const { return _has_method_handle_invokes; } 487 void set_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; } 488 489 bool is_lazy_critical_native() const { return _lazy_critical_native; } 490 void set_lazy_critical_native(bool z) { _lazy_critical_native = z; } 491 492 bool has_wide_vectors() const { return _has_wide_vectors; } 493 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; } 494 495 int comp_level() const { return _comp_level; } 496 497 // Support for oops in scopes and relocs: 498 // Note: index 0 is reserved for null. 499 oop oop_at(int index) const { return index == 0 ? (oop) NULL: *oop_addr_at(index); } 500 oop* oop_addr_at(int index) const { // for GC 501 // relocation indexes are biased by 1 (because 0 is reserved) 502 assert(index > 0 && index <= oops_size(), "must be a valid non-zero index"); 503 assert(!_oops_are_stale, "oops are stale"); 504 return &oops_begin()[index - 1]; 505 } 506 507 // Support for meta data in scopes and relocs: 508 // Note: index 0 is reserved for null. 509 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); } 510 Metadata** metadata_addr_at(int index) const { // for GC 511 // relocation indexes are biased by 1 (because 0 is reserved) 512 assert(index > 0 && index <= metadata_size(), "must be a valid non-zero index"); 513 return &metadata_begin()[index - 1]; 514 } 515 516 void copy_values(GrowableArray<jobject>* oops); 517 void copy_values(GrowableArray<Metadata*>* metadata); 518 519 // Relocation support 520 private: 521 void fix_oop_relocations(address begin, address end, bool initialize_immediates); 522 inline void initialize_immediate_oop(oop* dest, jobject handle); 523 524 public: 525 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); } 526 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); } 527 void verify_oop_relocations(); 528 529 bool is_at_poll_return(address pc); 530 bool is_at_poll_or_poll_return(address pc); 531 532 // Scavengable oop support 533 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; } 534 protected: 535 enum { sl_on_list = 0x01, sl_marked = 0x10 }; 536 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; } 537 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; } 538 // assertion-checking and pruning logic uses the bits of _scavenge_root_state 539 #ifndef PRODUCT 540 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; } 541 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; } 542 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; } 543 // N.B. there is no positive marked query, and we only use the not_marked query for asserts. 544 #endif //PRODUCT 545 nmethod* scavenge_root_link() const { return _scavenge_root_link; } 546 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; } 547 548 public: 549 550 // Sweeper support 551 long stack_traversal_mark() { return _stack_traversal_mark; } 552 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; } 553 554 // Exception cache support 555 ExceptionCache* exception_cache() const { return _exception_cache; } 556 void set_exception_cache(ExceptionCache *ec) { _exception_cache = ec; } 557 address handler_for_exception_and_pc(Handle exception, address pc); 558 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler); 559 void clean_exception_cache(BoolObjectClosure* is_alive); 560 561 // implicit exceptions support 562 address continuation_for_implicit_exception(address pc); 563 564 // On-stack replacement support 565 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; } 566 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; } 567 void invalidate_osr_method(); 568 nmethod* osr_link() const { return _osr_link; } 569 void set_osr_link(nmethod *n) { _osr_link = n; } 570 571 // tells whether frames described by this nmethod can be deoptimized 572 // note: native wrappers cannot be deoptimized. 573 bool can_be_deoptimized() const { return is_java_method(); } 574 575 // Inline cache support 576 void clear_inline_caches(); 577 void cleanup_inline_caches(); 578 bool inlinecache_check_contains(address addr) const { 579 return (addr >= code_begin() && addr < verified_entry_point()); 580 } 581 582 // Verify calls to dead methods have been cleaned. 583 void verify_clean_inline_caches(); 584 // Verify and count cached icholder relocations. 585 int verify_icholder_relocations(); 586 // Check that all metadata is still alive 587 void verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive); 588 589 // unlink and deallocate this nmethod 590 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not 591 // expected to use any other private methods/data in this class. 592 593 protected: 594 void flush(); 595 596 public: 597 // When true is returned, it is unsafe to remove this nmethod even if 598 // it is a zombie, since the VM or the ServiceThread might still be 599 // using it. 600 bool is_locked_by_vm() const { return _lock_count >0; } 601 602 // See comment at definition of _last_seen_on_stack 603 void mark_as_seen_on_stack(); 604 bool can_not_entrant_be_converted(); 605 606 // Evolution support. We make old (discarded) compiled methods point to new Method*s. 607 void set_method(Method* method) { _method = method; } 608 609 // GC support 610 void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred); 611 // The parallel versions are used by G1. 612 bool do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred); 613 void do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred); 614 // Unload a nmethod if the *root object is dead. 615 bool can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred); 616 617 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, 618 OopClosure* f); 619 void oops_do(OopClosure* f) { oops_do(f, false); } 620 void oops_do(OopClosure* f, bool allow_zombie); 621 bool detect_scavenge_root_oops(); 622 void verify_scavenge_root_oops() PRODUCT_RETURN; 623 624 bool test_set_oops_do_mark(); 625 static void oops_do_marking_prologue(); 626 static void oops_do_marking_epilogue(); 627 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; } 628 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; } 629 630 // ScopeDesc for an instruction 631 ScopeDesc* scope_desc_at(address pc); 632 633 private: 634 ScopeDesc* scope_desc_in(address begin, address end); 635 636 address* orig_pc_addr(const frame* fr) { return (address*) ((address)fr->unextended_sp() + _orig_pc_offset); } 637 638 PcDesc* find_pc_desc_internal(address pc, bool approximate); 639 640 PcDesc* find_pc_desc(address pc, bool approximate) { 641 PcDesc* desc = _pc_desc_cache.last_pc_desc(); 642 if (desc != NULL && desc->pc_offset() == pc - code_begin()) { 643 return desc; 644 } 645 return find_pc_desc_internal(pc, approximate); 646 } 647 648 public: 649 // ScopeDesc retrieval operation 650 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); } 651 // pc_desc_near returns the first PcDesc at or after the givne pc. 652 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); } 653 654 public: 655 // copying of debugging information 656 void copy_scopes_pcs(PcDesc* pcs, int count); 657 void copy_scopes_data(address buffer, int size); 658 659 // Deopt 660 // Return true is the PC is one would expect if the frame is being deopted. 661 bool is_deopt_pc (address pc) { return is_deopt_entry(pc) || is_deopt_mh_entry(pc); } 662 bool is_deopt_entry (address pc) { return pc == deopt_handler_begin(); } 663 bool is_deopt_mh_entry(address pc) { return pc == deopt_mh_handler_begin(); } 664 // Accessor/mutator for the original pc of a frame before a frame was deopted. 665 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); } 666 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; } 667 668 static address get_deopt_original_pc(const frame* fr); 669 670 // MethodHandle 671 bool is_method_handle_return(address return_pc); 672 673 // jvmti support: 674 void post_compiled_method_load_event(); 675 jmethodID get_and_cache_jmethod_id(); 676 677 // verify operations 678 void verify(); 679 void verify_scopes(); 680 void verify_interrupt_point(address interrupt_point); 681 682 // printing support 683 void print() const; 684 void print_code(); 685 void print_relocations() PRODUCT_RETURN; 686 void print_pcs() PRODUCT_RETURN; 687 void print_scopes() PRODUCT_RETURN; 688 void print_dependencies() PRODUCT_RETURN; 689 void print_value_on(outputStream* st) const PRODUCT_RETURN; 690 void print_calls(outputStream* st) PRODUCT_RETURN; 691 void print_handler_table() PRODUCT_RETURN; 692 void print_nul_chk_table() PRODUCT_RETURN; 693 void print_nmethod(bool print_code); 694 695 // need to re-define this from CodeBlob else the overload hides it 696 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); } 697 void print_on(outputStream* st, const char* msg) const; 698 699 // Logging 700 void log_identity(xmlStream* log) const; 701 void log_new_nmethod() const; 702 void log_state_change() const; 703 704 // Prints block-level comments, including nmethod specific block labels: 705 virtual void print_block_comment(outputStream* stream, address block_begin) const { 706 print_nmethod_labels(stream, block_begin); 707 CodeBlob::print_block_comment(stream, block_begin); 708 } 709 void print_nmethod_labels(outputStream* stream, address block_begin) const; 710 711 // Prints a comment for one native instruction (reloc info, pc desc) 712 void print_code_comment_on(outputStream* st, int column, address begin, address end); 713 static void print_statistics() PRODUCT_RETURN; 714 715 // Compiler task identification. Note that all OSR methods 716 // are numbered in an independent sequence if CICountOSR is true, 717 // and native method wrappers are also numbered independently if 718 // CICountNative is true. 719 int compile_id() const { return _compile_id; } 720 const char* compile_kind() const; 721 722 // For debugging 723 // CompiledIC* IC_at(char* p) const; 724 // PrimitiveIC* primitiveIC_at(char* p) const; 725 oop embeddedOop_at(address p); 726 727 // tells if any of this method's dependencies have been invalidated 728 // (this is expensive!) 729 static void check_all_dependencies(DepChange& changes); 730 731 // tells if this compiled method is dependent on the given changes, 732 // and the changes have invalidated it 733 bool check_dependency_on(DepChange& changes); 734 735 // Evolution support. Tells if this compiled method is dependent on any of 736 // methods m() of class dependee, such that if m() in dependee is replaced, 737 // this compiled method will have to be deoptimized. 738 bool is_evol_dependent_on(Klass* dependee); 739 740 // Fast breakpoint support. Tells if this compiled method is 741 // dependent on the given method. Returns true if this nmethod 742 // corresponds to the given method as well. 743 bool is_dependent_on_method(Method* dependee); 744 745 // is it ok to patch at address? 746 bool is_patchable_at(address instr_address); 747 748 // UseBiasedLocking support 749 ByteSize native_receiver_sp_offset() { 750 return _native_receiver_sp_offset; 751 } 752 ByteSize native_basic_lock_sp_offset() { 753 return _native_basic_lock_sp_offset; 754 } 755 756 // support for code generation 757 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); } 758 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); } 759 static int entry_bci_offset() { return offset_of(nmethod, _entry_bci); } 760 761 // RedefineClasses support. Mark metadata in nmethods as on_stack so that 762 // redefine classes doesn't purge it. 763 static void mark_on_stack(nmethod* nm) { 764 nm->metadata_do(Metadata::mark_on_stack); 765 } 766 void metadata_do(void f(Metadata*)); 767 }; 768 769 // Locks an nmethod so its code will not get removed and it will not 770 // be made into a zombie, even if it is a not_entrant method. After the 771 // nmethod becomes a zombie, if CompiledMethodUnload event processing 772 // needs to be done, then lock_nmethod() is used directly to keep the 773 // generated code from being reused too early. 774 class nmethodLocker : public StackObj { 775 nmethod* _nm; 776 777 public: 778 779 // note: nm can be NULL 780 // Only JvmtiDeferredEvent::compiled_method_unload_event() 781 // should pass zombie_ok == true. 782 static void lock_nmethod(nmethod* nm, bool zombie_ok = false); 783 static void unlock_nmethod(nmethod* nm); // (ditto) 784 785 nmethodLocker(address pc); // derive nm from pc 786 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); } 787 nmethodLocker() { _nm = NULL; } 788 ~nmethodLocker() { unlock_nmethod(_nm); } 789 790 nmethod* code() { return _nm; } 791 void set_code(nmethod* new_nm) { 792 unlock_nmethod(_nm); // note: This works even if _nm==new_nm. 793 _nm = new_nm; 794 lock_nmethod(_nm); 795 } 796 }; 797 798 #endif // SHARE_VM_CODE_NMETHOD_HPP