1 /*
2 * Copyright (c) 1997, 2026, 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_OOPS_METHOD_HPP
26 #define SHARE_OOPS_METHOD_HPP
27
28 #include "code/compressedStream.hpp"
29 #include "compiler/compilerDefinitions.hpp"
30 #include "oops/annotations.hpp"
31 #include "oops/constantPool.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/methodFlags.hpp"
34 #include "oops/oop.hpp"
35 #include "utilities/accessFlags.hpp"
36 #include "utilities/align.hpp"
37 #include "utilities/growableArray.hpp"
38 #include "utilities/macros.hpp"
39 #include "utilities/vmEnums.hpp"
40 #if INCLUDE_JFR
41 #include "jfr/support/jfrTraceIdExtension.hpp"
42 #endif
43
44
45 // A Method represents a Java method.
46 //
47 // Note that most applications load thousands of methods, so keeping the size of this
48 // class small has a big impact on footprint.
49 //
50 // Note that native_function and signature_handler have to be at fixed offsets
51 // (required by the interpreter)
52 //
53 // Method embedded field layout (after declared fields):
54 // [EMBEDDED native_function (present only if native) ]
55 // [EMBEDDED signature_handler (present only if native) ]
56
57 class CheckedExceptionElement;
58 class LocalVariableTableElement;
59 class AdapterHandlerEntry;
60 class MethodData;
61 class MethodCounters;
62 class MethodTrainingData;
63 class ConstMethod;
64 class InlineTableSizes;
65 class nmethod;
66 class InterpreterOopMap;
67
68 class Method : public Metadata {
69 friend class VMStructs;
70 friend class MethodTest;
71 private:
72 // If you add a new field that points to any metaspace object, you
73 // must add this field to Method::metaspace_pointers_do().
74 ConstMethod* _constMethod; // Method read-only data.
75 MethodData* _method_data;
76 MethodCounters* _method_counters;
77 AdapterHandlerEntry* _adapter;
78 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
79 AccessFlags _access_flags; // Access flags
80 MethodFlags _flags;
81
82 u2 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
83
84 JFR_ONLY(DEFINE_TRACE_FLAG;)
85
86 #ifndef PRODUCT
87 int64_t _compiled_invocation_count;
88
89 Symbol* _name;
90 #endif
91 // Entry point for calling both from and to the interpreter.
92 address _i2i_entry; // All-args-on-stack calling convention
93 // Entry point for calling from compiled code, to compiled code if it exists
94 // or else the interpreter.
95 volatile address _from_compiled_entry; // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
96 // The entry point for calling both from and to compiled code is
97 // "_code->entry_point()". Because of tiered compilation and de-opt, this
98 // field can come and go. It can transition from null to not-null at any
99 // time (whenever a compile completes). It can transition from not-null to
100 // null only at safepoints (because of a de-opt).
101 nmethod* volatile _code; // Points to the corresponding piece of native code
102 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
103
104 // Constructor
105 Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name);
106 public:
107
108 static Method* allocate(ClassLoaderData* loader_data,
109 int byte_code_size,
110 AccessFlags access_flags,
111 InlineTableSizes* sizes,
112 ConstMethod::MethodType method_type,
113 Symbol* name,
114 TRAPS);
115
116 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
117 Method(){}
118
119 virtual bool is_method() const { return true; }
120
121 #if INCLUDE_CDS
122 void remove_unshareable_info();
123 void restore_unshareable_info(TRAPS);
124 static void restore_archived_method_handle_intrinsic(methodHandle m, TRAPS);
125 #endif
126
127 // accessors for instance variables
128
129 ConstMethod* constMethod() const { return _constMethod; }
130 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
131
132
133 static address make_adapters(const methodHandle& mh, TRAPS);
134 address from_compiled_entry() const;
135 address from_interpreted_entry() const;
136
137 // access flag
138 AccessFlags access_flags() const { return _access_flags; }
139 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
140
141 // name
142 Symbol* name() const { return constants()->symbol_at(name_index()); }
143 u2 name_index() const { return constMethod()->name_index(); }
144 void set_name_index(int index) { constMethod()->set_name_index(index); }
145
146 // signature
147 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
148 u2 signature_index() const { return constMethod()->signature_index(); }
149 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
150
151 // generics support
152 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : nullptr); }
153 u2 generic_signature_index() const { return constMethod()->generic_signature_index(); }
154
155 // annotations support
156 AnnotationArray* annotations() const {
157 return constMethod()->method_annotations();
158 }
159 AnnotationArray* parameter_annotations() const {
160 return constMethod()->parameter_annotations();
161 }
162 AnnotationArray* annotation_default() const {
163 return constMethod()->default_annotations();
164 }
165 AnnotationArray* type_annotations() const {
166 return constMethod()->type_annotations();
167 }
168
169 // Helper routine: get klass name + "." + method name + signature as
170 // C string, for the purpose of providing more useful
171 // fatal error handling. The string is allocated in resource
172 // area if a buffer is not provided by the caller.
173 char* name_and_sig_as_C_string(bool use_double_colon = false) const;
174 char* name_and_sig_as_C_string(char* buf, int size) const;
175
176 // Static routine in the situations we don't have a Method*
177 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, bool use_double_colon = false);
178 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
179
180 // Get return type + klass name + "." + method name + ( parameters types )
181 // as a C string or print it to an outputStream.
182 // This is to be used to assemble strings passed to Java, so that
183 // the text more resembles Java code. Used in exception messages.
184 // Memory is allocated in the resource area; the caller needs
185 // a ResourceMark.
186 const char* external_name() const;
187 void print_external_name(outputStream *os) const;
188
189 static const char* external_name( Klass* klass, Symbol* method_name, Symbol* signature);
190 static void print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature);
191
192 Bytecodes::Code java_code_at(int bci) const {
193 return Bytecodes::java_code_at(this, bcp_from(bci));
194 }
195 Bytecodes::Code code_at(int bci) const {
196 return Bytecodes::code_at(this, bcp_from(bci));
197 }
198
199 // JVMTI breakpoints
200 #if !INCLUDE_JVMTI
201 Bytecodes::Code orig_bytecode_at(int bci) const {
202 ShouldNotReachHere();
203 return Bytecodes::_shouldnotreachhere;
204 }
205 void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
206 ShouldNotReachHere();
207 };
208 u2 number_of_breakpoints() const {return 0;}
209 #else // !INCLUDE_JVMTI
210 Bytecodes::Code orig_bytecode_at(int bci) const;
211 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
212 void set_breakpoint(int bci);
213 void clear_breakpoint(int bci);
214 void clear_all_breakpoints();
215 // Tracking number of breakpoints, for fullspeed debugging.
216 // Only mutated by VM thread.
217 inline u2 number_of_breakpoints() const;
218 inline void incr_number_of_breakpoints(Thread* current);
219 inline void decr_number_of_breakpoints(Thread* current);
220 // Initialization only
221 inline void clear_number_of_breakpoints();
222 #endif // !INCLUDE_JVMTI
223
224 // index into InstanceKlass methods() array
225 // note: also used by jfr
226 u2 method_idnum() const { return constMethod()->method_idnum(); }
227 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
228
229 u2 orig_method_idnum() const { return constMethod()->orig_method_idnum(); }
230 void set_orig_method_idnum(u2 idnum) { constMethod()->set_orig_method_idnum(idnum); }
231
232 // code size
233 u2 code_size() const { return constMethod()->code_size(); }
234
235 // method size in words
236 int method_size() const { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }
237
238 // constant pool for Klass* holding this method
239 ConstantPool* constants() const { return constMethod()->constants(); }
240 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
241
242 // max stack
243 // return original max stack size for method verification
244 u2 verifier_max_stack() const { return constMethod()->max_stack(); }
245 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
246 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
247
248 // max locals
249 u2 max_locals() const { return constMethod()->max_locals(); }
250 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
251
252 void set_deprecated() { constMethod()->set_deprecated(); }
253 bool deprecated() const { return constMethod()->deprecated(); }
254
255 void set_deprecated_for_removal() { constMethod()->set_deprecated_for_removal(); }
256 bool deprecated_for_removal() const { return constMethod()->deprecated_for_removal(); }
257
258 inline int highest_comp_level() const;
259 void set_highest_comp_level(int level);
260 int highest_osr_comp_level() const;
261 void set_highest_osr_comp_level(int level);
262
263 #ifdef COMPILER2
264 // Count of times method was exited via exception while interpreting
265 inline void interpreter_throwout_increment(Thread* current);
266 #endif // COMPILER2
267
268 inline int interpreter_throwout_count() const;
269
270 u2 size_of_parameters() const { return constMethod()->size_of_parameters(); }
271
272 bool has_stackmap_table() const {
273 return constMethod()->has_stackmap_table();
274 }
275
276 Array<u1>* stackmap_data() const {
277 return constMethod()->stackmap_data();
278 }
279
280 void set_stackmap_data(Array<u1>* sd) {
281 constMethod()->set_stackmap_data(sd);
282 }
283
284 // exception handler table
285 bool has_exception_handler() const
286 { return constMethod()->has_exception_table(); }
287 u2 exception_table_length() const
288 { return constMethod()->exception_table_length(); }
289 ExceptionTableElement* exception_table_start() const
290 { return constMethod()->exception_table_start(); }
291
292 // Finds the first entry point bci of an exception handler for an
293 // exception of klass ex_klass thrown at throw_bci. A value of null
294 // for ex_klass indicates that the exception klass is not known; in
295 // this case it matches any constraint class. Returns -1 if the
296 // exception cannot be handled in this method. The handler
297 // constraint classes are loaded if necessary. Note that this may
298 // throw an exception if loading of the constraint classes causes
299 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
300 // If an exception is thrown, returns the bci of the
301 // exception handler which caused the exception to be thrown, which
302 // is needed for proper retries. See, for example,
303 // InterpreterRuntime::exception_handler_for_exception.
304 static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
305
306 static bool register_native(Klass* k,
307 Symbol* name,
308 Symbol* signature,
309 address entry,
310 TRAPS);
311
312 // method data access
313 MethodData* method_data() const {
314 return _method_data;
315 }
316 void set_method_data(MethodData* data);
317
318 MethodTrainingData* training_data_or_null() const;
319 bool init_training_data(MethodTrainingData* td);
320
321 // mark an exception handler as entered (used to prune dead catch blocks in C2)
322 void set_exception_handler_entered(int handler_bci);
323
324 MethodCounters* method_counters() const {
325 return _method_counters;
326 }
327
328 void clear_method_counters() {
329 _method_counters = nullptr;
330 }
331
332 bool init_method_counters(MethodCounters* counters);
333
334 inline int prev_event_count() const;
335 inline void set_prev_event_count(int count);
336 inline jlong prev_time() const;
337 inline void set_prev_time(jlong time);
338 inline float rate() const;
339 inline void set_rate(float rate);
340
341 inline int invocation_count() const;
342 inline int backedge_count() const;
343
344 bool was_executed_more_than(int n);
345 bool was_never_executed() { return !was_executed_more_than(0); }
346
347 static void build_profiling_method_data(const methodHandle& method, TRAPS);
348 static bool install_training_method_data(const methodHandle& method);
349 static MethodCounters* build_method_counters(Thread* current, Method* m);
350
351 inline int interpreter_invocation_count() const;
352
353 #ifndef PRODUCT
354 int64_t compiled_invocation_count() const { return _compiled_invocation_count;}
355 void set_compiled_invocation_count(int count) { _compiled_invocation_count = (int64_t)count; }
356 #else
357 // for PrintMethodData in a product build
358 int64_t compiled_invocation_count() const { return 0; }
359 #endif // not PRODUCT
360
361 // nmethod/verified compiler entry
362 address verified_code_entry();
363 bool check_code() const; // Not inline to avoid circular ref
364 nmethod* code() const;
365
366 // Locks NMethodState_lock if not held.
367 void unlink_code(nmethod *compare);
368 // Locks NMethodState_lock if not held.
369 void unlink_code();
370
371 private:
372 // Either called with NMethodState_lock held or from constructor.
373 void clear_code();
374
375 void clear_method_data() {
376 _method_data = nullptr;
377 }
378
379 public:
380 static void set_code(const methodHandle& mh, nmethod* code);
381 void set_adapter_entry(AdapterHandlerEntry* adapter) {
382 _adapter = adapter;
383 }
384 void set_from_compiled_entry(address entry) {
385 _from_compiled_entry = entry;
386 }
387
388 address get_i2c_entry();
389 address get_c2i_entry();
390 address get_c2i_unverified_entry();
391 address get_c2i_no_clinit_check_entry();
392 AdapterHandlerEntry* adapter() const {
393 return _adapter;
394 }
395 // setup entry points
396 void link_method(const methodHandle& method, TRAPS);
397 // clear entry points. Used by sharing code during dump time
398 void unlink_method() NOT_CDS_RETURN;
399 void remove_unshareable_flags() NOT_CDS_RETURN;
400
401 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
402 virtual MetaspaceObj::Type type() const { return MethodType; }
403
404 // vtable index
405 enum VtableIndexFlag {
406 // Valid vtable indexes are non-negative (>= 0).
407 // These few negative values are used as sentinels.
408 itable_index_max = -10, // first itable index, growing downward
409 pending_itable_index = -9, // itable index will be assigned
410 invalid_vtable_index = -4, // distinct from any valid vtable index
411 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
412 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
413 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
414 };
415 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
416 bool has_vtable_index() const { return _vtable_index >= 0; }
417 int vtable_index() const { return _vtable_index; }
418 void set_vtable_index(int index);
419 DEBUG_ONLY(bool valid_itable_index() const { return _vtable_index <= pending_itable_index; })
420 bool has_itable_index() const { return _vtable_index <= itable_index_max; }
421 int itable_index() const { assert(valid_itable_index(), "");
422 return itable_index_max - _vtable_index; }
423 void set_itable_index(int index);
424
425 // interpreter entry
426 address interpreter_entry() const { return _i2i_entry; }
427 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
428 void set_interpreter_entry(address entry) {
429 if (_i2i_entry != entry) {
430 _i2i_entry = entry;
431 }
432 if (_from_interpreted_entry != entry) {
433 _from_interpreted_entry = entry;
434 }
435 }
436
437 // native function (used for native methods only)
438 enum {
439 native_bind_event_is_interesting = true
440 };
441 address native_function() const { return *(native_function_addr()); }
442
443 // Must specify a real function (not null).
444 // Use clear_native_function() to unregister.
445 void set_native_function(address function, bool post_event_flag);
446 bool has_native_function() const;
447 void clear_native_function();
448
449 // signature handler (used for native methods only)
450 address signature_handler() const { return *(signature_handler_addr()); }
451 void set_signature_handler(address handler);
452
453 // Interpreter oopmap support.
454 // If handle is already available, call with it for better performance.
455 void mask_for(int bci, InterpreterOopMap* mask);
456 void mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask);
457
458 // operations on invocation counter
459 void print_invocation_count(outputStream* st);
460
461 // byte codes
462 void set_code(address code) { return constMethod()->set_code(code); }
463 address code_base() const { return constMethod()->code_base(); }
464 bool contains(address bcp) const { return constMethod()->contains(bcp); }
465
466 // prints byte codes
467 void print_codes(int flags = 0, bool buffered = true) const { print_codes_on(tty, flags, buffered); }
468 void print_codes_on(outputStream* st, int flags = 0, bool buffered = true) const;
469 void print_codes_on(int from, int to, outputStream* st, int flags = 0, bool buffered = true) const;
470
471 // method parameters
472 bool has_method_parameters() const
473 { return constMethod()->has_method_parameters(); }
474 int method_parameters_length() const
475 { return constMethod()->method_parameters_length(); }
476 MethodParametersElement* method_parameters_start() const
477 { return constMethod()->method_parameters_start(); }
478
479 // checked exceptions
480 u2 checked_exceptions_length() const
481 { return constMethod()->checked_exceptions_length(); }
482 CheckedExceptionElement* checked_exceptions_start() const
483 { return constMethod()->checked_exceptions_start(); }
484
485 // localvariable table
486 bool has_localvariable_table() const
487 { return constMethod()->has_localvariable_table(); }
488 u2 localvariable_table_length() const
489 { return constMethod()->localvariable_table_length(); }
490 LocalVariableTableElement* localvariable_table_start() const
491 { return constMethod()->localvariable_table_start(); }
492
493 bool has_linenumber_table() const
494 { return constMethod()->has_linenumber_table(); }
495 u_char* compressed_linenumber_table() const
496 { return constMethod()->compressed_linenumber_table(); }
497
498 // method holder (the Klass* holding this method)
499 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
500
501 Symbol* klass_name() const; // returns the name of the method holder
502 BasicType result_type() const { return constMethod()->result_type(); }
503 bool is_returning_oop() const { BasicType r = result_type(); return is_reference_type(r); }
504 bool is_returning_fp() const { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }
505
506 // Checked exceptions thrown by this method (resolved to mirrors)
507 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
508
509 // Access flags
510 bool is_public() const { return access_flags().is_public(); }
511 bool is_private() const { return access_flags().is_private(); }
512 bool is_protected() const { return access_flags().is_protected(); }
513 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
514 bool is_static() const { return access_flags().is_static(); }
515 bool is_final() const { return access_flags().is_final(); }
516 bool is_synchronized() const { return access_flags().is_synchronized();}
517 bool is_native() const { return access_flags().is_native(); }
518 bool is_abstract() const { return access_flags().is_abstract(); }
519 bool is_synthetic() const { return access_flags().is_synthetic(); }
520
521 // returns true if contains only return operation
522 bool is_empty_method() const;
523
524 // returns true if this is a vanilla constructor
525 bool is_vanilla_constructor() const;
526
527 // checks method and its method holder
528 bool is_final_method() const;
529 bool is_final_method(AccessFlags class_access_flags) const;
530 // interface method declared with 'default' - excludes private interface methods
531 bool is_default_method() const;
532
533 // true if method needs no dynamic dispatch (final and/or no vtable entry)
534 bool can_be_statically_bound() const;
535 bool can_be_statically_bound(InstanceKlass* context) const;
536 bool can_be_statically_bound(AccessFlags class_access_flags) const;
537
538 // true if method can omit stack trace in throw in compiled code.
539 bool can_omit_stack_trace();
540
541 // Flags getting and setting.
542 #define M_STATUS_GET_SET(name, ignore) \
543 bool name() const { return _flags.name(); } \
544 void set_##name(bool x) { _flags.set_##name(x); } \
545 void set_##name() { _flags.set_##name(true); }
546 M_STATUS_DO(M_STATUS_GET_SET)
547 #undef M_STATUS_GET_SET
548
549 // returns true if the method has any backward branches.
550 bool has_loops() {
551 return has_loops_flag_init() ? has_loops_flag() : compute_has_loops_flag();
552 };
553
554 bool compute_has_loops_flag();
555 bool set_has_loops() {
556 // set both the flags and that it's been initialized.
557 set_has_loops_flag();
558 set_has_loops_flag_init();
559 return true;
560 }
561
562 // returns true if the method has any monitors.
563 bool has_monitors() const { return is_synchronized() || has_monitor_bytecodes(); }
564
565 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
566 // properly nest in the method. It might return false, even though they actually nest properly, since the info.
567 // has not been computed yet.
568 bool guaranteed_monitor_matching() const { return monitor_matching(); }
569 void set_guaranteed_monitor_matching() { set_monitor_matching(); }
570
571 // returns true if the method is an accessor function (setter/getter).
572 bool is_accessor() const;
573
574 // returns true if the method is a getter
575 bool is_getter() const;
576
577 // returns true if the method is a setter
578 bool is_setter() const;
579
580 // returns true if the method does nothing but return a constant of primitive type
581 bool is_constant_getter() const;
582
583 // returns true if the method is static OR if the classfile version < 51
584 bool has_valid_initializer_flags() const;
585
586 // returns true if the method name is <clinit> and the method has
587 // valid static initializer flags.
588 bool is_static_initializer() const;
589
590 // returns true if the method name is <init>
591 bool is_object_initializer() const;
592
593 // returns true if the method name is wait0
594 bool is_object_wait0() const;
595
596 // compiled code support
597 // NOTE: code() is inherently racy as deopt can be clearing code
598 // simultaneously. Use with caution.
599 bool has_compiled_code() const;
600
601 bool needs_clinit_barrier() const;
602
603 // sizing
604 static int header_size() {
605 return align_up((int)sizeof(Method), wordSize) / wordSize;
606 }
607 static int size(bool is_native);
608 int size() const { return method_size(); }
609 void log_touched(Thread* current);
610 static void print_touched_methods(outputStream* out);
611
612 // interpreter support
613 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
614 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
615 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
616 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
617
618 static ByteSize method_counters_offset() {
619 return byte_offset_of(Method, _method_counters);
620 }
621 #ifndef PRODUCT
622 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
623 #endif // not PRODUCT
624 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
625 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
626 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
627 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
628 static ByteSize itable_index_offset() { return byte_offset_of(Method, _vtable_index ); }
629
630 // for code generation
631 static ByteSize method_data_offset() { return byte_offset_of(Method, _method_data); }
632 static ByteSize intrinsic_id_offset() { return byte_offset_of(Method, _intrinsic_id); }
633 static int intrinsic_id_size_in_bytes() { return sizeof(u2); }
634
635 // Static methods that are used to implement member methods where an exposed this pointer
636 // is needed due to possible GCs
637 static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
638
639 // Returns the byte code index from the byte code pointer
640 int bci_from(address bcp) const;
641 address bcp_from(int bci) const;
642 address bcp_from(address bcp) const;
643 int validate_bci_from_bcp(address bcp) const;
644 int validate_bci(int bci) const;
645
646 // Returns the line number for a bci if debugging information for the method is prowided,
647 // -1 is returned otherwise.
648 int line_number_from_bci(int bci) const;
649
650 // Reflection support
651 bool is_overridden_in(Klass* k) const;
652
653 // Stack walking support
654 bool is_ignored_by_security_stack_walk() const;
655
656 // JSR 292 support
657 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
658 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
659 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
660 static methodHandle make_method_handle_intrinsic(vmIntrinsicID iid, // _invokeBasic, _linkToVirtual
661 Symbol* signature, //anything at all
662 TRAPS);
663 // Some special methods don't need to be findable by nmethod iterators and are permanent.
664 bool can_be_allocated_in_NonNMethod_space() const { return is_method_handle_intrinsic(); }
665
666 // Continuation
667 inline bool is_continuation_enter_intrinsic() const;
668 inline bool is_continuation_yield_intrinsic() const;
669 inline bool is_continuation_native_intrinsic() const;
670 inline bool is_special_native_intrinsic() const;
671
672 static Klass* check_non_bcp_klass(Klass* klass);
673
674 enum {
675 // How many extra stack entries for invokedynamic
676 extra_stack_entries_for_jsr292 = 1
677 };
678
679 // this operates only on invoke methods:
680 // presize interpreter frames for extra interpreter stack entries, if needed
681 // Account for the extra appendix argument for invokehandle/invokedynamic
682 static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
683 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize
684
685 // RedefineClasses() support:
686 bool on_stack() const { return on_stack_flag(); }
687 void set_on_stack(const bool value);
688
689 void record_gc_epoch();
690
691 // see the definition in Method*.cpp for the gory details
692 bool should_not_be_cached() const;
693
694 // Rewriting support
695 static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
696 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
697
698 // jmethodID handling
699 // Because the useful life-span of a jmethodID cannot be determined,
700 // once created they are never reclaimed. The methods to which they refer,
701 // however, can be GC'ed away if the class is unloaded or if the method is
702 // made obsolete or deleted -- in these cases, the jmethodID
703 // refers to null (as is the case for any weak reference).
704 static jmethodID make_jmethod_id(ClassLoaderData* cld, Method* mh);
705
706 // Use resolve_jmethod_id() in situations where the caller is expected
707 // to provide a valid jmethodID; the only sanity checks are in asserts;
708 // result guaranteed not to be null.
709 static Method* resolve_jmethod_id(jmethodID mid);
710
711 // Use checked_resolve_jmethod_id() in situations where the caller
712 // should provide a valid jmethodID, but might not. Null is returned
713 // when the jmethodID does not refer to a valid method.
714 static Method* checked_resolve_jmethod_id(jmethodID mid);
715
716 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
717 static bool validate_jmethod_id(jmethodID mid);
718
719 // Clear jmethodID
720 void clear_jmethod_id();
721 static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
722
723 // Get this method's jmethodID -- allocate if it doesn't exist
724 jmethodID jmethod_id();
725
726 // Lookup the jmethodID for this method. Return null if not found.
727 // NOTE that this function can be called from a signal handler
728 // (see AsyncGetCallTrace support for Forte Analyzer) and this
729 // needs to be async-safe. No allocation should be done and
730 // so handles are not used to avoid deadlock.
731 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
732
733 // Support for inlining of intrinsic methods
734 vmIntrinsicID intrinsic_id() const { return (vmIntrinsicID) _intrinsic_id; }
735 void set_intrinsic_id(vmIntrinsicID id) { _intrinsic_id = (u2) id; }
736
737 // Helper routines for intrinsic_id() and vmIntrinsics::method().
738 void init_intrinsic_id(vmSymbolID klass_id); // updates from _none if a match
739 static vmSymbolID klass_id_for_intrinsics(const Klass* holder);
740
741 bool caller_sensitive() const { return constMethod()->caller_sensitive(); }
742 void set_caller_sensitive() { constMethod()->set_caller_sensitive(); }
743
744 bool changes_current_thread() const { return constMethod()->changes_current_thread(); }
745 void set_changes_current_thread() { constMethod()->set_changes_current_thread(); }
746
747 bool jvmti_hide_events() const { return constMethod()->jvmti_hide_events(); }
748 void set_jvmti_hide_events() { constMethod()->set_jvmti_hide_events(); }
749
750 bool jvmti_mount_transition() const { return constMethod()->jvmti_mount_transition(); }
751 void set_jvmti_mount_transition() { constMethod()->set_jvmti_mount_transition(); }
752
753 bool is_hidden() const { return constMethod()->is_hidden(); }
754 void set_is_hidden() { constMethod()->set_is_hidden(); }
755
756 bool is_scoped() const { return constMethod()->is_scoped(); }
757 void set_scoped() { constMethod()->set_is_scoped(); }
758
759 bool intrinsic_candidate() const { return constMethod()->intrinsic_candidate(); }
760 void set_intrinsic_candidate() { constMethod()->set_intrinsic_candidate(); }
761
762 bool has_injected_profile() const { return constMethod()->has_injected_profile(); }
763 void set_has_injected_profile() { constMethod()->set_has_injected_profile(); }
764
765 bool has_reserved_stack_access() const { return constMethod()->reserved_stack_access(); }
766 void set_has_reserved_stack_access() { constMethod()->set_reserved_stack_access(); }
767
768 JFR_ONLY(DEFINE_TRACE_FLAG_ACCESSOR;)
769
770 ConstMethod::MethodType method_type() const {
771 return _constMethod->method_type();
772 }
773 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
774
775 // On-stack replacement support
776 bool has_osr_nmethod(int level, bool match_level) {
777 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != nullptr;
778 }
779
780 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
781 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
782 }
783
784 // Find if klass for method is loaded
785 bool is_klass_loaded_by_klass_index(int klass_index) const;
786 bool is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved = false) const;
787
788 // Indicates whether compilation failed earlier for this method, or
789 // whether it is not compilable for another reason like having a
790 // breakpoint set in it.
791 bool is_not_compilable(int comp_level = CompLevel_any) const;
792 void set_not_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
793 void set_not_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
794 set_not_compilable(reason, comp_level, false);
795 }
796 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
797 void set_not_osr_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
798 void set_not_osr_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
799 set_not_osr_compilable(reason, comp_level, false);
800 }
801 bool is_always_compilable() const;
802
803 private:
804 void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
805
806 public:
807 MethodCounters* get_method_counters(Thread* current) {
808 if (_method_counters == nullptr) {
809 build_method_counters(current, this);
810 }
811 return _method_counters;
812 }
813
814 void clear_is_not_c1_compilable() { set_is_not_c1_compilable(false); }
815 void clear_is_not_c2_compilable() { set_is_not_c2_compilable(false); }
816 void clear_is_not_c2_osr_compilable() { set_is_not_c2_osr_compilable(false); }
817
818 // not_c1_osr_compilable == not_c1_compilable
819 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); }
820 void set_is_not_c1_osr_compilable() { set_is_not_c1_compilable(); }
821 void clear_is_not_c1_osr_compilable() { clear_is_not_c1_compilable(); }
822
823 // Background compilation support
824 void clear_queued_for_compilation() { set_queued_for_compilation(false); }
825
826 // Resolve all classes in signature, return 'true' if successful
827 static bool load_signature_classes(const methodHandle& m, TRAPS);
828
829 // Printing
830 void print_short_name(outputStream* st = tty) const; // prints as klassname::methodname; Exposed so field engineers can debug VM
831 #if INCLUDE_JVMTI
832 void print_name(outputStream* st = tty) const; // prints as "virtual void foo(int)"; exposed for -Xlog:redefine+class
833 #else
834 void print_name(outputStream* st = tty) const PRODUCT_RETURN; // prints as "virtual void foo(int)"
835 #endif
836
837 typedef int (*method_comparator_func)(Method* a, Method* b);
838
839 // Helper routine used for method sorting
840 static void sort_methods(Array<Method*>* methods, bool set_idnums = true, method_comparator_func func = nullptr);
841
842 // Deallocation function for redefine classes or if an error occurs
843 void deallocate_contents(ClassLoaderData* loader_data);
844
845 void release_C_heap_structures();
846
847 Method* get_new_method() const {
848 InstanceKlass* holder = method_holder();
849 Method* new_method = holder->method_with_idnum(orig_method_idnum());
850
851 assert(new_method != nullptr, "method_with_idnum() should not be null");
852 assert(this != new_method, "sanity check");
853 return new_method;
854 }
855
856 // Printing
857 #ifndef PRODUCT
858 void print_on(outputStream* st) const;
859 #endif
860 void print_value_on(outputStream* st) const;
861 void print_access_flags(outputStream* st) const;
862 void print_linkage_flags(outputStream* st) const PRODUCT_RETURN;
863
864 const char* internal_name() const { return "{method}"; }
865
866 // Check for valid method pointer
867 static bool has_method_vptr(const void* ptr);
868 static bool is_valid_method(const Method* m);
869
870 // Verify
871 void verify() { verify_on(tty); }
872 void verify_on(outputStream* st);
873
874 private:
875
876 // Inlined elements
877 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
878 address* signature_handler_addr() const { return native_function_addr() + 1; }
879 };
880
881
882 // Utility class for compressing line number tables
883
884 class CompressedLineNumberWriteStream: public CompressedWriteStream {
885 private:
886 int _bci;
887 int _line;
888 public:
889 // Constructor
890 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
891 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
892
893 // Write (bci, line number) pair to stream
894 void write_pair_regular(int bci_delta, int line_delta);
895
896 // If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
897 // we save it as one byte, otherwise we write a 0xFF escape character
898 // and use regular compression. 0x0 is used as end-of-stream terminator.
899 void write_pair_inline(int bci, int line);
900
901 void write_pair(int bci, int line);
902
903 // Write end-of-stream marker
904 void write_terminator() { write_byte(0); }
905 };
906
907
908 // Utility class for decompressing line number tables
909
910 class CompressedLineNumberReadStream: public CompressedReadStream {
911 private:
912 int _bci;
913 int _line;
914 public:
915 // Constructor
916 CompressedLineNumberReadStream(u_char* buffer);
917 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
918 bool read_pair();
919 // Accessing bci and line number (after calling read_pair)
920 int bci() const { return _bci; }
921 int line() const { return _line; }
922 };
923
924
925 #if INCLUDE_JVMTI
926
927 /// Fast Breakpoints.
928
929 // If this structure gets more complicated (because bpts get numerous),
930 // move it into its own header.
931
932 // There is presently no provision for concurrent access
933 // to breakpoint lists, which is only OK for JVMTI because
934 // breakpoints are written only at safepoints, and are read
935 // concurrently only outside of safepoints.
936
937 class BreakpointInfo : public CHeapObj<mtClass> {
938 friend class VMStructs;
939 private:
940 Bytecodes::Code _orig_bytecode;
941 int _bci;
942 u2 _name_index; // of method
943 u2 _signature_index; // of method
944 BreakpointInfo* _next; // simple storage allocation
945
946 public:
947 BreakpointInfo(Method* m, int bci);
948
949 // accessors
950 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
951 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
952 int bci() { return _bci; }
953
954 BreakpointInfo* next() const { return _next; }
955 void set_next(BreakpointInfo* n) { _next = n; }
956
957 // helps for searchers
958 bool match(const Method* m, int bci) {
959 return bci == _bci && match(m);
960 }
961
962 bool match(const Method* m) {
963 return _name_index == m->name_index() &&
964 _signature_index == m->signature_index();
965 }
966
967 void set(Method* method);
968 void clear(Method* method);
969 };
970
971 #endif // INCLUDE_JVMTI
972
973 // Utility class for access exception handlers
974 class ExceptionTable : public StackObj {
975 private:
976 ExceptionTableElement* _table;
977 u2 _length;
978
979 public:
980 ExceptionTable(const Method* m) {
981 if (m->has_exception_handler()) {
982 _table = m->exception_table_start();
983 _length = m->exception_table_length();
984 } else {
985 _table = nullptr;
986 _length = 0;
987 }
988 }
989
990 u2 length() const {
991 return _length;
992 }
993
994 u2 start_pc(int idx) const {
995 assert(idx < _length, "out of bounds");
996 return _table[idx].start_pc;
997 }
998
999 void set_start_pc(int idx, u2 value) {
1000 assert(idx < _length, "out of bounds");
1001 _table[idx].start_pc = value;
1002 }
1003
1004 u2 end_pc(int idx) const {
1005 assert(idx < _length, "out of bounds");
1006 return _table[idx].end_pc;
1007 }
1008
1009 void set_end_pc(int idx, u2 value) {
1010 assert(idx < _length, "out of bounds");
1011 _table[idx].end_pc = value;
1012 }
1013
1014 u2 handler_pc(int idx) const {
1015 assert(idx < _length, "out of bounds");
1016 return _table[idx].handler_pc;
1017 }
1018
1019 void set_handler_pc(int idx, u2 value) {
1020 assert(idx < _length, "out of bounds");
1021 _table[idx].handler_pc = value;
1022 }
1023
1024 u2 catch_type_index(int idx) const {
1025 assert(idx < _length, "out of bounds");
1026 return _table[idx].catch_type_index;
1027 }
1028
1029 void set_catch_type_index(int idx, u2 value) {
1030 assert(idx < _length, "out of bounds");
1031 _table[idx].catch_type_index = value;
1032 }
1033 };
1034
1035 #endif // SHARE_OOPS_METHOD_HPP