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