1 /*
2 * Copyright (c) 1997, 2025, 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_CODE_NMETHOD_HPP
26 #define SHARE_CODE_NMETHOD_HPP
27
28 #include "code/codeBlob.hpp"
29 #include "code/pcDesc.hpp"
30 #include "compiler/compilerDefinitions.hpp"
31 #include "oops/metadata.hpp"
32 #include "oops/method.hpp"
33
34 class AbstractCompiler;
35 class CompiledDirectCall;
36 class CompiledIC;
37 class CompiledICData;
38 class CompileTask;
39 class DepChange;
40 class Dependencies;
41 class DirectiveSet;
42 class DebugInformationRecorder;
43 class ExceptionHandlerTable;
44 class ImplicitExceptionTable;
45 class JvmtiThreadState;
46 class MetadataClosure;
47 class NativeCallWrapper;
48 class OopIterateClosure;
49 class ScopeDesc;
50 class xmlStream;
51
52 // This class is used internally by nmethods, to cache
53 // exception/pc/handler information.
54
55 class ExceptionCache : public CHeapObj<mtCode> {
56 friend class VMStructs;
57 private:
58 enum { cache_size = 16 };
59 Klass* _exception_type;
60 address _pc[cache_size];
61 address _handler[cache_size];
62 volatile int _count;
63 ExceptionCache* volatile _next;
64 ExceptionCache* _purge_list_next;
65
66 inline address pc_at(int index);
67 void set_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; }
68
69 inline address handler_at(int index);
70 void set_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; }
71
72 inline int count();
73 // increment_count is only called under lock, but there may be concurrent readers.
74 void increment_count();
75
76 public:
77
78 ExceptionCache(Handle exception, address pc, address handler);
79
80 Klass* exception_type() { return _exception_type; }
81 ExceptionCache* next();
82 void set_next(ExceptionCache *ec);
83 ExceptionCache* purge_list_next() { return _purge_list_next; }
84 void set_purge_list_next(ExceptionCache *ec) { _purge_list_next = ec; }
85
86 address match(Handle exception, address pc);
87 bool match_exception_with_space(Handle exception) ;
88 address test_address(address addr);
89 bool add_address_and_handler(address addr, address handler) ;
90 };
91
92 // cache pc descs found in earlier inquiries
93 class PcDescCache {
94 private:
95 enum { cache_size = 4 };
96 // The array elements MUST be volatile! Several threads may modify
97 // and read from the cache concurrently. find_pc_desc_internal has
98 // returned wrong results. C++ compiler (namely xlC12) may duplicate
99 // C++ field accesses if the elements are not volatile.
100 typedef PcDesc* PcDescPtr;
101 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
102 public:
103 PcDescCache() { DEBUG_ONLY(_pc_descs[0] = nullptr); }
104 void init_to(PcDesc* initial_pc_desc);
105 PcDesc* find_pc_desc(int pc_offset, bool approximate);
106 void add_pc_desc(PcDesc* pc_desc);
107 PcDesc* last_pc_desc() { return _pc_descs[0]; }
108 };
109
110 class PcDescContainer : public CHeapObj<mtCode> {
111 private:
112 PcDescCache _pc_desc_cache;
113 public:
114 PcDescContainer(PcDesc* initial_pc_desc) { _pc_desc_cache.init_to(initial_pc_desc); }
115
116 PcDesc* find_pc_desc_internal(address pc, bool approximate, address code_begin,
117 PcDesc* lower, PcDesc* upper);
118
119 PcDesc* find_pc_desc(address pc, bool approximate, address code_begin, PcDesc* lower, PcDesc* upper)
120 #ifdef PRODUCT
121 {
122 PcDesc* desc = _pc_desc_cache.last_pc_desc();
123 assert(desc != nullptr, "PcDesc cache should be initialized already");
124 if (desc->pc_offset() == (pc - code_begin)) {
125 // Cached value matched
126 return desc;
127 }
128 return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
129 }
130 #endif
131 ;
132 };
133
134 // nmethods (native methods) are the compiled code versions of Java methods.
135 //
136 // An nmethod contains:
137 // - Header (the nmethod structure)
138 // - Constant part (doubles, longs and floats used in nmethod)
139 // - Code part:
140 // - Code body
141 // - Exception handler
142 // - Stub code
143 // - OOP table
144 //
145 // As a CodeBlob, an nmethod references [mutable data] allocated on the C heap:
146 // - CodeBlob relocation data
147 // - Metainfo
148 // - JVMCI data
149 //
150 // An nmethod references [immutable data] allocated on C heap:
151 // - Dependency assertions data
152 // - Implicit null table array
153 // - Handler entry point array
154 // - Debugging information:
155 // - Scopes data array
156 // - Scopes pcs array
157 // - JVMCI speculations array
158 // - Nmethod reference counter
159
160 #if INCLUDE_JVMCI
161 class FailedSpeculation;
162 class JVMCINMethodData;
163 #endif
164
165 class nmethod : public CodeBlob {
166 friend class VMStructs;
167 friend class JVMCIVMStructs;
168 friend class CodeCache; // scavengable oops
169 friend class JVMCINMethodData;
170 friend class DeoptimizationScope;
171
172 #define ImmutableDataReferencesCounterSize ((int)sizeof(int))
173
174 private:
175
176 // Used to track in which deoptimize handshake this method will be deoptimized.
177 uint64_t _deoptimization_generation;
178
179 uint64_t _gc_epoch;
180
181 Method* _method;
182
183 // To reduce header size union fields which usages do not overlap.
184 union {
185 // To support simple linked-list chaining of nmethods:
186 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
187 struct {
188 // These are used for compiled synchronized native methods to
189 // locate the owner and stack slot for the BasicLock. They are
190 // needed because there is no debug information for compiled native
191 // wrappers and the oop maps are insufficient to allow
192 // frame::retrieve_receiver() to work. Currently they are expected
193 // to be byte offsets from the Java stack pointer for maximum code
194 // sharing between platforms. JVMTI's GetLocalInstance() uses these
195 // offsets to find the receiver for non-static native wrapper frames.
196 ByteSize _native_receiver_sp_offset;
197 ByteSize _native_basic_lock_sp_offset;
198 };
199 };
200
201 // nmethod's read-only data
202 address _immutable_data;
203
204 PcDescContainer* _pc_desc_container;
205 ExceptionCache* volatile _exception_cache;
206
207 void* _gc_data;
208
209 struct oops_do_mark_link; // Opaque data type.
210 static nmethod* volatile _oops_do_mark_nmethods;
211 oops_do_mark_link* volatile _oops_do_mark_link;
212
213 CompiledICData* _compiled_ic_data;
214
215 // offsets for entry points
216 address _osr_entry_point; // entry point for on stack replacement
217 uint16_t _entry_offset; // entry point with class check
218 uint16_t _verified_entry_offset; // entry point without class check
219 // TODO: can these be uint16_t, seem rely on -1 CodeOffset, can change later...
220 address _inline_entry_point; // inline type entry point (unpack all inline type args) with class check
221 address _verified_inline_entry_point; // inline type entry point (unpack all inline type args) without class check
222 address _verified_inline_ro_entry_point; // inline type entry point (unpack receiver only) without class check
223 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
224 int _immutable_data_size;
225
226 // _consts_offset == _content_offset because SECT_CONSTS is first in code buffer
227
228 int _skipped_instructions_size;
229
230 int _stub_offset;
231
232 // Offsets for different stubs section parts
233 int _exception_offset;
234 // All deoptee's will resume execution at this location described by
235 // this offset.
236 int _deopt_handler_offset;
237 // Offset (from insts_end) of the unwind handler if it exists
238 int16_t _unwind_handler_offset;
239 // Number of arguments passed on the stack
240 uint16_t _num_stack_arg_slots;
241
242 uint16_t _oops_size;
243 #if INCLUDE_JVMCI
244 // _metadata_size is not specific to JVMCI. In the non-JVMCI case, it can be derived as:
245 // _metadata_size = mutable_data_size - relocation_size
246 uint16_t _metadata_size;
247 #endif
248
249 // Offset in immutable data section
250 // _dependencies_offset == 0
251 uint16_t _nul_chk_table_offset;
252 uint16_t _handler_table_offset; // This table could be big in C1 code
253 int _scopes_pcs_offset;
254 int _scopes_data_offset;
255 #if INCLUDE_JVMCI
256 int _speculations_offset;
257 #endif
258 int _immutable_data_reference_counter_offset;
259
260 // location in frame (offset for sp) that deopt can store the original
261 // pc during a deopt.
262 int _orig_pc_offset;
263
264 int _compile_id; // which compilation made this nmethod
265 CompLevel _comp_level; // compilation level (s1)
266 CompilerType _compiler_type; // which compiler made this nmethod (u1)
267
268 // Local state used to keep track of whether unloading is happening or not
269 volatile uint8_t _is_unloading_state;
270
271 // Protected by NMethodState_lock
272 volatile signed char _state; // {not_installed, in_use, not_entrant}
273
274 // set during construction
275 uint8_t _has_unsafe_access:1, // May fault due to unsafe access.
276 _has_wide_vectors:1, // Preserve wide vectors at safepoints
277 _has_monitors:1, // Fastpath monitor detection for continuations
278 _has_scoped_access:1, // used by for shared scope closure (scopedMemoryAccess.cpp)
279 _has_flushed_dependencies:1, // Used for maintenance of dependencies (under CodeCache_lock)
280 _is_unlinked:1, // mark during class unloading
281 _load_reported:1; // used by jvmti to track if an event has been posted for this nmethod
282
283 enum DeoptimizationStatus : u1 {
284 not_marked,
285 deoptimize,
286 deoptimize_noupdate,
287 deoptimize_done
288 };
289
290 volatile DeoptimizationStatus _deoptimization_status; // Used for stack deoptimization
291
292 DeoptimizationStatus deoptimization_status() const {
293 return AtomicAccess::load(&_deoptimization_status);
294 }
295
296 // Initialize fields to their default values
297 void init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets);
298
299 // Post initialization
300 void post_init();
301
302 // For native wrappers
303 nmethod(Method* method,
304 CompilerType type,
305 int nmethod_size,
306 int compile_id,
307 CodeOffsets* offsets,
308 CodeBuffer *code_buffer,
309 int frame_size,
310 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
311 ByteSize basic_lock_sp_offset, /* synchronized natives only */
312 OopMapSet* oop_maps,
313 int mutable_data_size);
314
315 // For normal JIT compiled code
316 nmethod(Method* method,
317 CompilerType type,
318 int nmethod_size,
319 int immutable_data_size,
320 int mutable_data_size,
321 int compile_id,
322 int entry_bci,
323 address immutable_data,
324 CodeOffsets* offsets,
325 int orig_pc_offset,
326 DebugInformationRecorder *recorder,
327 Dependencies* dependencies,
328 CodeBuffer *code_buffer,
329 int frame_size,
330 OopMapSet* oop_maps,
331 ExceptionHandlerTable* handler_table,
332 ImplicitExceptionTable* nul_chk_table,
333 AbstractCompiler* compiler,
334 CompLevel comp_level
335 #if INCLUDE_JVMCI
336 , char* speculations = nullptr,
337 int speculations_len = 0,
338 JVMCINMethodData* jvmci_data = nullptr
339 #endif
340 );
341
342 nmethod(const nmethod &nm);
343
344 // helper methods
345 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
346 void* operator new(size_t size, int nmethod_size, CodeBlobType code_blob_type) throw();
347
348 // For method handle intrinsics: Try MethodNonProfiled, MethodProfiled and NonNMethod.
349 // Attention: Only allow NonNMethod space for special nmethods which don't need to be
350 // findable by nmethod iterators! In particular, they must not contain oops!
351 void* operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw();
352
353 const char* reloc_string_for(u_char* begin, u_char* end);
354
355 bool try_transition(signed char new_state);
356
357 // Returns true if this thread changed the state of the nmethod or
358 // false if another thread performed the transition.
359 bool make_entrant() { Unimplemented(); return false; }
360 void inc_decompile_count();
361
362 // Inform external interfaces that a compiled method has been unloaded
363 void post_compiled_method_unload();
364
365 PcDesc* find_pc_desc(address pc, bool approximate) {
366 if (_pc_desc_container == nullptr) return nullptr; // native method
367 return _pc_desc_container->find_pc_desc(pc, approximate, code_begin(), scopes_pcs_begin(), scopes_pcs_end());
368 }
369
370 // STW two-phase nmethod root processing helpers.
371 //
372 // When determining liveness of a given nmethod to do code cache unloading,
373 // some collectors need to do different things depending on whether the nmethods
374 // need to absolutely be kept alive during root processing; "strong"ly reachable
375 // nmethods are known to be kept alive at root processing, but the liveness of
376 // "weak"ly reachable ones is to be determined later.
377 //
378 // We want to allow strong and weak processing of nmethods by different threads
379 // at the same time without heavy synchronization. Additional constraints are
380 // to make sure that every nmethod is processed a minimal amount of time, and
381 // nmethods themselves are always iterated at most once at a particular time.
382 //
383 // Note that strong processing work must be a superset of weak processing work
384 // for this code to work.
385 //
386 // We store state and claim information in the _oops_do_mark_link member, using
387 // the two LSBs for the state and the remaining upper bits for linking together
388 // nmethods that were already visited.
389 // The last element is self-looped, i.e. points to itself to avoid some special
390 // "end-of-list" sentinel value.
391 //
392 // _oops_do_mark_link special values:
393 //
394 // _oops_do_mark_link == nullptr: the nmethod has not been visited at all yet, i.e.
395 // is Unclaimed.
396 //
397 // For other values, its lowest two bits indicate the following states of the nmethod:
398 //
399 // weak_request (WR): the nmethod has been claimed by a thread for weak processing
400 // weak_done (WD): weak processing has been completed for this nmethod.
401 // strong_request (SR): the nmethod has been found to need strong processing while
402 // being weak processed.
403 // strong_done (SD): strong processing has been completed for this nmethod .
404 //
405 // The following shows the _only_ possible progressions of the _oops_do_mark_link
406 // pointer.
407 //
408 // Given
409 // N as the nmethod
410 // X the current next value of _oops_do_mark_link
411 //
412 // Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
413 // a single thread.
414 // Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
415 // completed (as above) another thread found that the nmethod needs strong
416 // processing after all.
417 // Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
418 // thread finds that the nmethod needs strong processing, marks it as such and
419 // terminates. The original thread completes strong processing.
420 // Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
421 // the beginning by a single thread.
422 //
423 // "|" describes the concatenation of bits in _oops_do_mark_link.
424 //
425 // The diagram also describes the threads responsible for changing the nmethod to
426 // the next state by marking the _transition_ with (C) and (O), which mean "current"
427 // and "other" thread respectively.
428 //
429
430 // States used for claiming nmethods during root processing.
431 static const uint claim_weak_request_tag = 0;
432 static const uint claim_weak_done_tag = 1;
433 static const uint claim_strong_request_tag = 2;
434 static const uint claim_strong_done_tag = 3;
435
436 static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
437 assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
438 assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
439 return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
440 }
441
442 static uint extract_state(oops_do_mark_link* link) {
443 return (uint)((uintptr_t)link & 0x3);
444 }
445
446 static nmethod* extract_nmethod(oops_do_mark_link* link) {
447 return (nmethod*)((uintptr_t)link & ~0x3);
448 }
449
450 void oops_do_log_change(const char* state);
451
452 static bool oops_do_has_weak_request(oops_do_mark_link* next) {
453 return extract_state(next) == claim_weak_request_tag;
454 }
455
456 static bool oops_do_has_any_strong_state(oops_do_mark_link* next) {
457 return extract_state(next) >= claim_strong_request_tag;
458 }
459
460 // Attempt Unclaimed -> N|WR transition. Returns true if successful.
461 bool oops_do_try_claim_weak_request();
462
463 // Attempt Unclaimed -> N|SD transition. Returns the current link.
464 oops_do_mark_link* oops_do_try_claim_strong_done();
465 // Attempt N|WR -> X|WD transition. Returns nullptr if successful, X otherwise.
466 nmethod* oops_do_try_add_to_list_as_weak_done();
467
468 // Attempt X|WD -> N|SR transition. Returns the current link.
469 oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
470 // Attempt X|WD -> X|SD transition. Returns true if successful.
471 bool oops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);
472
473 // Do the N|SD -> X|SD transition.
474 void oops_do_add_to_list_as_strong_done();
475
476 // Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
477 // transitions).
478 void oops_do_set_strong_done(nmethod* old_head);
479
480 public:
481 // If you change anything in this enum please patch
482 // vmStructs_jvmci.cpp accordingly.
483 enum class InvalidationReason : s1 {
484 NOT_INVALIDATED = -1,
485 C1_CODEPATCH,
486 C1_DEOPTIMIZE,
487 C1_DEOPTIMIZE_FOR_PATCHING,
488 C1_PREDICATE_FAILED_TRAP,
489 CI_REPLAY,
490 UNLOADING,
491 UNLOADING_COLD,
492 JVMCI_INVALIDATE,
493 JVMCI_MATERIALIZE_VIRTUAL_OBJECT,
494 JVMCI_REPLACED_WITH_NEW_CODE,
495 JVMCI_REPROFILE,
496 MARKED_FOR_DEOPTIMIZATION,
497 MISSING_EXCEPTION_HANDLER,
498 NOT_USED,
499 OSR_INVALIDATION_BACK_BRANCH,
500 OSR_INVALIDATION_FOR_COMPILING_WITH_C1,
501 OSR_INVALIDATION_OF_LOWER_LEVEL,
502 SET_NATIVE_FUNCTION,
503 UNCOMMON_TRAP,
504 WHITEBOX_DEOPTIMIZATION,
505 ZOMBIE,
506 INVALIDATION_REASONS_COUNT
507 };
508
509
510 static const char* invalidation_reason_to_string(InvalidationReason invalidation_reason) {
511 switch (invalidation_reason) {
512 case InvalidationReason::C1_CODEPATCH:
513 return "C1 code patch";
514 case InvalidationReason::C1_DEOPTIMIZE:
515 return "C1 deoptimized";
516 case InvalidationReason::C1_DEOPTIMIZE_FOR_PATCHING:
517 return "C1 deoptimize for patching";
518 case InvalidationReason::C1_PREDICATE_FAILED_TRAP:
519 return "C1 predicate failed trap";
520 case InvalidationReason::CI_REPLAY:
521 return "CI replay";
522 case InvalidationReason::JVMCI_INVALIDATE:
523 return "JVMCI invalidate";
524 case InvalidationReason::JVMCI_MATERIALIZE_VIRTUAL_OBJECT:
525 return "JVMCI materialize virtual object";
526 case InvalidationReason::JVMCI_REPLACED_WITH_NEW_CODE:
527 return "JVMCI replaced with new code";
528 case InvalidationReason::JVMCI_REPROFILE:
529 return "JVMCI reprofile";
530 case InvalidationReason::MARKED_FOR_DEOPTIMIZATION:
531 return "marked for deoptimization";
532 case InvalidationReason::MISSING_EXCEPTION_HANDLER:
533 return "missing exception handler";
534 case InvalidationReason::NOT_USED:
535 return "not used";
536 case InvalidationReason::OSR_INVALIDATION_BACK_BRANCH:
537 return "OSR invalidation back branch";
538 case InvalidationReason::OSR_INVALIDATION_FOR_COMPILING_WITH_C1:
539 return "OSR invalidation for compiling with C1";
540 case InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL:
541 return "OSR invalidation of lower level";
542 case InvalidationReason::SET_NATIVE_FUNCTION:
543 return "set native function";
544 case InvalidationReason::UNCOMMON_TRAP:
545 return "uncommon trap";
546 case InvalidationReason::WHITEBOX_DEOPTIMIZATION:
547 return "whitebox deoptimization";
548 case InvalidationReason::ZOMBIE:
549 return "zombie";
550 default: {
551 assert(false, "Unhandled reason");
552 return "Unknown";
553 }
554 }
555 }
556
557 // create nmethod with entry_bci
558 static nmethod* new_nmethod(const methodHandle& method,
559 int compile_id,
560 int entry_bci,
561 CodeOffsets* offsets,
562 int orig_pc_offset,
563 DebugInformationRecorder* recorder,
564 Dependencies* dependencies,
565 CodeBuffer *code_buffer,
566 int frame_size,
567 OopMapSet* oop_maps,
568 ExceptionHandlerTable* handler_table,
569 ImplicitExceptionTable* nul_chk_table,
570 AbstractCompiler* compiler,
571 CompLevel comp_level
572 #if INCLUDE_JVMCI
573 , char* speculations = nullptr,
574 int speculations_len = 0,
575 JVMCINMethodData* jvmci_data = nullptr
576 #endif
577 );
578
579 // Relocate the nmethod to the code heap identified by code_blob_type.
580 // Returns nullptr if the code heap does not have enough space, the
581 // nmethod is unrelocatable, or the nmethod is invalidated during relocation,
582 // otherwise the relocated nmethod. The original nmethod will be marked not entrant.
583 nmethod* relocate(CodeBlobType code_blob_type);
584
585 static nmethod* new_native_nmethod(const methodHandle& method,
586 int compile_id,
587 CodeBuffer *code_buffer,
588 int vep_offset,
589 int frame_complete,
590 int frame_size,
591 ByteSize receiver_sp_offset,
592 ByteSize basic_lock_sp_offset,
593 OopMapSet* oop_maps,
594 int exception_handler = -1);
595
596 Method* method () const { return _method; }
597 bool is_native_method() const { return _method != nullptr && _method->is_native(); }
598 bool is_java_method () const { return _method != nullptr && !_method->is_native(); }
599 bool is_osr_method () const { return _entry_bci != InvocationEntryBci; }
600
601 bool is_relocatable();
602
603 // Compiler task identification. Note that all OSR methods
604 // are numbered in an independent sequence if CICountOSR is true,
605 // and native method wrappers are also numbered independently if
606 // CICountNative is true.
607 int compile_id() const { return _compile_id; }
608 const char* compile_kind() const;
609
610 inline bool is_compiled_by_c1 () const { return _compiler_type == compiler_c1; }
611 inline bool is_compiled_by_c2 () const { return _compiler_type == compiler_c2; }
612 inline bool is_compiled_by_jvmci() const { return _compiler_type == compiler_jvmci; }
613 CompilerType compiler_type () const { return _compiler_type; }
614 const char* compiler_name () const;
615
616 // boundaries for different parts
617 address consts_begin () const { return content_begin(); }
618 address consts_end () const { return code_begin() ; }
619 address insts_begin () const { return code_begin() ; }
620 address insts_end () const { return header_begin() + _stub_offset ; }
621 address stub_begin () const { return header_begin() + _stub_offset ; }
622 address stub_end () const { return code_end() ; }
623 address exception_begin () const { return header_begin() + _exception_offset ; }
624 address deopt_handler_begin () const { return header_begin() + _deopt_handler_offset ; }
625 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (insts_end() - _unwind_handler_offset) : nullptr; }
626 oop* oops_begin () const { return (oop*) data_begin(); }
627 oop* oops_end () const { return (oop*) data_end(); }
628
629 // mutable data
630 Metadata** metadata_begin () const { return (Metadata**) (mutable_data_begin() + _relocation_size); }
631 #if INCLUDE_JVMCI
632 Metadata** metadata_end () const { return (Metadata**) (mutable_data_begin() + _relocation_size + _metadata_size); }
633 address jvmci_data_begin () const { return mutable_data_begin() + _relocation_size + _metadata_size; }
634 address jvmci_data_end () const { return mutable_data_end(); }
635 #else
636 Metadata** metadata_end () const { return (Metadata**) mutable_data_end(); }
637 #endif
638
639 // immutable data
640 address immutable_data_begin () const { return _immutable_data; }
641 address immutable_data_end () const { return _immutable_data + _immutable_data_size ; }
642 address dependencies_begin () const { return _immutable_data; }
643 address dependencies_end () const { return _immutable_data + _nul_chk_table_offset; }
644 address nul_chk_table_begin () const { return _immutable_data + _nul_chk_table_offset; }
645 address nul_chk_table_end () const { return _immutable_data + _handler_table_offset; }
646 address handler_table_begin () const { return _immutable_data + _handler_table_offset; }
647 address handler_table_end () const { return _immutable_data + _scopes_pcs_offset ; }
648 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(_immutable_data + _scopes_pcs_offset) ; }
649 PcDesc* scopes_pcs_end () const { return (PcDesc*)(_immutable_data + _scopes_data_offset) ; }
650 address scopes_data_begin () const { return _immutable_data + _scopes_data_offset ; }
651
652 #if INCLUDE_JVMCI
653 address scopes_data_end () const { return _immutable_data + _speculations_offset ; }
654 address speculations_begin () const { return _immutable_data + _speculations_offset ; }
655 address speculations_end () const { return _immutable_data + _immutable_data_reference_counter_offset ; }
656 #else
657 address scopes_data_end () const { return _immutable_data + _immutable_data_reference_counter_offset ; }
658 #endif
659 address immutable_data_references_counter_begin () const { return _immutable_data + _immutable_data_reference_counter_offset ; }
660
661 // Sizes
662 int immutable_data_size() const { return _immutable_data_size; }
663 int consts_size () const { return int( consts_end () - consts_begin ()); }
664 int insts_size () const { return int( insts_end () - insts_begin ()); }
665 int stub_size () const { return int( stub_end () - stub_begin ()); }
666 int oops_size () const { return int((address) oops_end () - (address) oops_begin ()); }
667 int metadata_size () const { return int((address) metadata_end () - (address) metadata_begin ()); }
668 int scopes_data_size () const { return int( scopes_data_end () - scopes_data_begin ()); }
669 int scopes_pcs_size () const { return int((intptr_t)scopes_pcs_end () - (intptr_t)scopes_pcs_begin ()); }
670 int dependencies_size () const { return int( dependencies_end () - dependencies_begin ()); }
671 int handler_table_size () const { return int( handler_table_end() - handler_table_begin()); }
672 int nul_chk_table_size () const { return int( nul_chk_table_end() - nul_chk_table_begin()); }
673 #if INCLUDE_JVMCI
674 int speculations_size () const { return int( speculations_end () - speculations_begin ()); }
675 int jvmci_data_size () const { return int( jvmci_data_end () - jvmci_data_begin ()); }
676 #endif
677
678 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
679 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
680
681 int skipped_instructions_size () const { return _skipped_instructions_size; }
682 int total_size() const;
683
684 // Containment
685 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); }
686 // Returns true if a given address is in the 'insts' section. The method
687 // insts_contains_inclusive() is end-inclusive.
688 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); }
689 bool insts_contains_inclusive(address addr) const { return insts_begin () <= addr && addr <= insts_end (); }
690 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); }
691 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
692 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
693 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
694 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
695 bool handler_table_contains (address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); }
696 bool nul_chk_table_contains (address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }
697
698 // entry points
699 address entry_point() const { return code_begin() + _entry_offset; } // normal entry point
700 address verified_entry_point() const { return code_begin() + _verified_entry_offset; } // if klass is correct
701 address inline_entry_point() const { return _inline_entry_point; } // inline type entry point (unpack all inline type args)
702 address verified_inline_entry_point() const { return _verified_inline_entry_point; } // inline type entry point (unpack all inline type args) without class check
703 address verified_inline_ro_entry_point() const { return _verified_inline_ro_entry_point; } // inline type entry point (only unpack receiver) without class check
704
705 enum : signed char { not_installed = -1, // in construction, only the owner doing the construction is
706 // allowed to advance state
707 in_use = 0, // executable nmethod
708 not_entrant = 1 // marked for deoptimization but activations may still exist
709 };
710
711 // flag accessing and manipulation
712 bool is_not_installed() const { return _state == not_installed; }
713 bool is_in_use() const { return _state <= in_use; }
714 bool is_not_entrant() const { return _state == not_entrant; }
715 int get_state() const { return _state; }
716
717 void clear_unloading_state();
718 // Heuristically deduce an nmethod isn't worth keeping around
719 bool is_cold();
720 bool is_unloading();
721 void do_unloading(bool unloading_occurred);
722
723 bool make_in_use() {
724 return try_transition(in_use);
725 }
726 // Make the nmethod non entrant. The nmethod will continue to be
727 // alive. It is used when an uncommon trap happens. Returns true
728 // if this thread changed the state of the nmethod or false if
729 // another thread performed the transition.
730 bool make_not_entrant(InvalidationReason invalidation_reason);
731 bool make_not_used() { return make_not_entrant(InvalidationReason::NOT_USED); }
732
733 bool is_marked_for_deoptimization() const { return deoptimization_status() != not_marked; }
734 bool has_been_deoptimized() const { return deoptimization_status() == deoptimize_done; }
735 void set_deoptimized_done();
736
737 bool update_recompile_counts() const {
738 // Update recompile counts when either the update is explicitly requested (deoptimize)
739 // or the nmethod is not marked for deoptimization at all (not_marked).
740 // The latter happens during uncommon traps when deoptimized nmethod is made not entrant.
741 DeoptimizationStatus status = deoptimization_status();
742 return status != deoptimize_noupdate && status != deoptimize_done;
743 }
744
745 // tells whether frames described by this nmethod can be deoptimized
746 // note: native wrappers cannot be deoptimized.
747 bool can_be_deoptimized() const { return is_java_method(); }
748
749 bool has_dependencies() { return dependencies_size() != 0; }
750 void print_dependencies_on(outputStream* out) PRODUCT_RETURN;
751 void flush_dependencies();
752
753 template<typename T>
754 T* gc_data() const { return reinterpret_cast<T*>(_gc_data); }
755 template<typename T>
756 void set_gc_data(T* gc_data) { _gc_data = reinterpret_cast<void*>(gc_data); }
757
758 bool has_unsafe_access() const { return _has_unsafe_access; }
759 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; }
760
761 bool has_monitors() const { return _has_monitors; }
762 void set_has_monitors(bool z) { _has_monitors = z; }
763
764 bool has_scoped_access() const { return _has_scoped_access; }
765 void set_has_scoped_access(bool z) { _has_scoped_access = z; }
766
767 bool has_wide_vectors() const { return _has_wide_vectors; }
768 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; }
769
770 bool needs_stack_repair() const {
771 if (is_compiled_by_c1()) {
772 return method()->c1_needs_stack_repair();
773 } else if (is_compiled_by_c2()) {
774 return method()->c2_needs_stack_repair();
775 } else {
776 return false;
777 }
778 }
779
780 bool has_flushed_dependencies() const { return _has_flushed_dependencies; }
781 void set_has_flushed_dependencies(bool z) {
782 assert(!has_flushed_dependencies(), "should only happen once");
783 _has_flushed_dependencies = z;
784 }
785
786 bool is_unlinked() const { return _is_unlinked; }
787 void set_is_unlinked() {
788 assert(!_is_unlinked, "already unlinked");
789 _is_unlinked = true;
790 }
791
792 int comp_level() const { return _comp_level; }
793
794 // Support for oops in scopes and relocs:
795 // Note: index 0 is reserved for null.
796 oop oop_at(int index) const;
797 oop oop_at_phantom(int index) const; // phantom reference
798 oop* oop_addr_at(int index) const { // for GC
799 // relocation indexes are biased by 1 (because 0 is reserved)
800 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
801 return &oops_begin()[index - 1];
802 }
803
804 // Support for meta data in scopes and relocs:
805 // Note: index 0 is reserved for null.
806 Metadata* metadata_at(int index) const { return index == 0 ? nullptr: *metadata_addr_at(index); }
807 Metadata** metadata_addr_at(int index) const { // for GC
808 // relocation indexes are biased by 1 (because 0 is reserved)
809 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
810 return &metadata_begin()[index - 1];
811 }
812
813 void copy_values(GrowableArray<jobject>* oops);
814 void copy_values(GrowableArray<Metadata*>* metadata);
815 void copy_values(GrowableArray<address>* metadata) {} // Nothing to do
816
817 // Relocation support
818 private:
819 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
820 inline void initialize_immediate_oop(oop* dest, jobject handle);
821
822 protected:
823 address oops_reloc_begin() const;
824
825 public:
826 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
827 void fix_oop_relocations() { fix_oop_relocations(nullptr, nullptr, false); }
828
829 bool is_at_poll_return(address pc);
830 bool is_at_poll_or_poll_return(address pc);
831
832 protected:
833 // Exception cache support
834 // Note: _exception_cache may be read and cleaned concurrently.
835 ExceptionCache* exception_cache() const { return _exception_cache; }
836 ExceptionCache* exception_cache_acquire() const;
837
838 public:
839 address handler_for_exception_and_pc(Handle exception, address pc);
840 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler);
841 void clean_exception_cache();
842
843 void add_exception_cache_entry(ExceptionCache* new_entry);
844 ExceptionCache* exception_cache_entry_for_exception(Handle exception);
845
846
847 // Deopt
848 // Return true is the PC is one would expect if the frame is being deopted.
849 inline bool is_deopt_pc(address pc);
850 inline bool is_deopt_entry(address pc);
851
852 // Accessor/mutator for the original pc of a frame before a frame was deopted.
853 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
854 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
855
856 const char* state() const;
857
858 bool inlinecache_check_contains(address addr) const {
859 return (addr >= code_begin() && addr < verified_entry_point());
860 }
861
862 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f);
863
864 // implicit exceptions support
865 address continuation_for_implicit_div0_exception(address pc) { return continuation_for_implicit_exception(pc, true); }
866 address continuation_for_implicit_null_exception(address pc) { return continuation_for_implicit_exception(pc, false); }
867
868 // Inline cache support for class unloading and nmethod unloading
869 private:
870 void cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all);
871
872 address continuation_for_implicit_exception(address pc, bool for_div0_check);
873
874 public:
875 // Serial version used by whitebox test
876 void cleanup_inline_caches_whitebox();
877
878 void clear_inline_caches();
879
880 // Execute nmethod barrier code, as if entering through nmethod call.
881 void run_nmethod_entry_barrier();
882
883 void verify_oop_relocations();
884
885 bool has_evol_metadata();
886
887 Method* attached_method(address call_pc);
888 Method* attached_method_before_pc(address pc);
889
890 // GC unloading support
891 // Cleans unloaded klasses and unloaded nmethods in inline caches
892
893 void unload_nmethod_caches(bool class_unloading_occurred);
894
895 void unlink_from_method();
896
897 // On-stack replacement support
898 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
899 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
900 nmethod* osr_link() const { return _osr_link; }
901 void set_osr_link(nmethod *n) { _osr_link = n; }
902 void invalidate_osr_method();
903
904 int num_stack_arg_slots(bool rounded = true) const {
905 return rounded ? align_up(_num_stack_arg_slots, 2) : _num_stack_arg_slots;
906 }
907
908 // Verify calls to dead methods have been cleaned.
909 void verify_clean_inline_caches();
910
911 // Unlink this nmethod from the system
912 void unlink();
913
914 // Deallocate this nmethod - called by the GC
915 void purge(bool unregister_nmethod);
916
917 // See comment at definition of _last_seen_on_stack
918 void mark_as_maybe_on_stack();
919 bool is_maybe_on_stack();
920
921 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
922 void set_method(Method* method) { _method = method; }
923
924 #if INCLUDE_JVMCI
925 // Gets the JVMCI name of this nmethod.
926 const char* jvmci_name();
927
928 // Records the pending failed speculation in the
929 // JVMCI speculation log associated with this nmethod.
930 void update_speculation(JavaThread* thread);
931
932 // Gets the data specific to a JVMCI compiled method.
933 // This returns a non-nullptr value iff this nmethod was
934 // compiled by the JVMCI compiler.
935 JVMCINMethodData* jvmci_nmethod_data() const {
936 return jvmci_data_size() == 0 ? nullptr : (JVMCINMethodData*) jvmci_data_begin();
937 }
938
939 // Returns true if the runtime should NOT collect deoptimization profile for a JVMCI
940 // compiled method
941 bool jvmci_skip_profile_deopt() const;
942 #endif
943
944 void oops_do(OopClosure* f);
945
946 // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
947 // nmethod.
948 bool oops_do_try_claim();
949
950 // Loom support for following nmethods on the stack
951 void follow_nmethod(OopIterateClosure* cl);
952
953 // Class containing callbacks for the oops_do_process_weak/strong() methods
954 // below.
955 class OopsDoProcessor {
956 public:
957 // Process the oops of the given nmethod based on whether it has been called
958 // in a weak or strong processing context, i.e. apply either weak or strong
959 // work on it.
960 virtual void do_regular_processing(nmethod* nm) = 0;
961 // Assuming that the oops of the given nmethod has already been its weak
962 // processing applied, apply the remaining strong processing part.
963 virtual void do_remaining_strong_processing(nmethod* nm) = 0;
964 };
965
966 // The following two methods do the work corresponding to weak/strong nmethod
967 // processing.
968 void oops_do_process_weak(OopsDoProcessor* p);
969 void oops_do_process_strong(OopsDoProcessor* p);
970
971 static void oops_do_marking_prologue();
972 static void oops_do_marking_epilogue();
973
974 private:
975 ScopeDesc* scope_desc_in(address begin, address end);
976
977 address* orig_pc_addr(const frame* fr);
978
979 // used by jvmti to track if the load events has been reported
980 bool load_reported() const { return _load_reported; }
981 void set_load_reported() { _load_reported = true; }
982
983 inline int get_immutable_data_references_counter() { return *((int*)immutable_data_references_counter_begin()); }
984 inline void set_immutable_data_references_counter(int count) { *((int*)immutable_data_references_counter_begin()) = count; }
985
986 static void add_delayed_compiled_method_load_event(nmethod* nm) NOT_CDS_RETURN;
987
988 public:
989 // ScopeDesc retrieval operation
990 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); }
991 // pc_desc_near returns the first PcDesc at or after the given pc.
992 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); }
993
994 // ScopeDesc for an instruction
995 ScopeDesc* scope_desc_at(address pc);
996 ScopeDesc* scope_desc_near(address pc);
997
998 // copying of debugging information
999 void copy_scopes_pcs(PcDesc* pcs, int count);
1000 void copy_scopes_data(address buffer, int size);
1001
1002 int orig_pc_offset() { return _orig_pc_offset; }
1003
1004 // Post successful compilation
1005 void post_compiled_method(CompileTask* task);
1006
1007 // jvmti support:
1008 void post_compiled_method_load_event(JvmtiThreadState* state = nullptr);
1009
1010 // verify operations
1011 void verify();
1012 void verify_scopes();
1013 void verify_interrupt_point(address interrupt_point, bool is_inline_cache);
1014
1015 // Disassemble this nmethod with additional debug information, e.g. information about blocks.
1016 void decode2(outputStream* st) const;
1017 void print_constant_pool(outputStream* st);
1018
1019 // Avoid hiding of parent's 'decode(outputStream*)' method.
1020 void decode(outputStream* st) const { decode2(st); } // just delegate here.
1021
1022 // AOT cache support
1023 static void post_delayed_compiled_method_load_events() NOT_CDS_RETURN;
1024
1025 // printing support
1026 void print_on_impl(outputStream* st) const;
1027 void print_code();
1028 void print_value_on_impl(outputStream* st) const;
1029
1030 #if defined(SUPPORT_DATA_STRUCTS)
1031 // print output in opt build for disassembler library
1032 void print_relocations() PRODUCT_RETURN;
1033 void print_pcs_on(outputStream* st);
1034 void print_scopes() { print_scopes_on(tty); }
1035 void print_scopes_on(outputStream* st) PRODUCT_RETURN;
1036 void print_handler_table();
1037 void print_nul_chk_table();
1038 void print_recorded_oop(int log_n, int index);
1039 void print_recorded_oops();
1040 void print_recorded_metadata();
1041
1042 void print_oops(outputStream* st); // oops from the underlying CodeBlob.
1043 void print_metadata(outputStream* st); // metadata in metadata pool.
1044 #else
1045 void print_pcs_on(outputStream* st) { return; }
1046 #endif
1047
1048 void print_calls(outputStream* st) PRODUCT_RETURN;
1049 static void print_statistics() PRODUCT_RETURN;
1050
1051 void maybe_print_nmethod(const DirectiveSet* directive);
1052 void print_nmethod(bool print_code);
1053
1054 void print_on_with_msg(outputStream* st, const char* msg) const;
1055
1056 // Logging
1057 void log_identity(xmlStream* log) const;
1058 void log_new_nmethod() const;
1059 void log_relocated_nmethod(nmethod* original) const;
1060 void log_state_change(InvalidationReason invalidation_reason) const;
1061
1062 // Prints block-level comments, including nmethod specific block labels:
1063 void print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels=true) const;
1064 const char* nmethod_section_label(address pos) const;
1065
1066 // returns whether this nmethod has code comments.
1067 bool has_code_comment(address begin, address end);
1068 // Prints a comment for one native instruction (reloc info, pc desc)
1069 void print_code_comment_on(outputStream* st, int column, address begin, address end);
1070
1071 // tells if this compiled method is dependent on the given changes,
1072 // and the changes have invalidated it
1073 bool check_dependency_on(DepChange& changes);
1074
1075 // Tells if this compiled method is dependent on the given method.
1076 // Returns true if this nmethod corresponds to the given method as well.
1077 // It is used for fast breakpoint support and updating the calling convention
1078 // in case of mismatch.
1079 bool is_dependent_on_method(Method* dependee);
1080
1081 // JVMTI's GetLocalInstance() support
1082 ByteSize native_receiver_sp_offset() {
1083 assert(is_native_method(), "sanity");
1084 return _native_receiver_sp_offset;
1085 }
1086 ByteSize native_basic_lock_sp_offset() {
1087 assert(is_native_method(), "sanity");
1088 return _native_basic_lock_sp_offset;
1089 }
1090
1091 // support for code generation
1092 static ByteSize osr_entry_point_offset() { return byte_offset_of(nmethod, _osr_entry_point); }
1093 static ByteSize state_offset() { return byte_offset_of(nmethod, _state); }
1094
1095 void metadata_do(MetadataClosure* f);
1096
1097 address call_instruction_address(address pc) const;
1098
1099 void make_deoptimized();
1100 void finalize_relocations();
1101
1102 class Vptr : public CodeBlob::Vptr {
1103 void print_on(const CodeBlob* instance, outputStream* st) const override {
1104 ttyLocker ttyl;
1105 instance->as_nmethod()->print_on_impl(st);
1106 }
1107 void print_value_on(const CodeBlob* instance, outputStream* st) const override {
1108 instance->as_nmethod()->print_value_on_impl(st);
1109 }
1110 };
1111
1112 static const Vptr _vpntr;
1113 };
1114
1115 struct NMethodMarkingScope : StackObj {
1116 NMethodMarkingScope() {
1117 nmethod::oops_do_marking_prologue();
1118 }
1119 ~NMethodMarkingScope() {
1120 nmethod::oops_do_marking_epilogue();
1121 }
1122 };
1123
1124 #endif // SHARE_CODE_NMETHOD_HPP