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_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/methodFlags.hpp"
33 #include "oops/instanceKlass.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 class AOTCodeEntry;
68
69 class Method : public Metadata {
70 friend class VMStructs;
71 friend class JVMCIVMStructs;
72 friend class MethodTest;
73 private:
74 // If you add a new field that points to any metaspace object, you
75 // must add this field to Method::metaspace_pointers_do().
76 ConstMethod* _constMethod; // Method read-only data.
77 MethodData* _method_data;
78 MethodCounters* _method_counters;
79 AdapterHandlerEntry* _adapter;
80 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
81 AccessFlags _access_flags; // Access flags
82 MethodFlags _flags;
83
84 u2 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
85
86 JFR_ONLY(DEFINE_TRACE_FLAG;)
87
88 #ifndef PRODUCT
89 int64_t _compiled_invocation_count;
90
91 Symbol* _name;
92 #endif
93 // Entry point for calling both from and to the interpreter.
94 address _i2i_entry; // All-args-on-stack calling convention
95 // Entry point for calling from compiled code, to compiled code if it exists
96 // or else the interpreter.
97 volatile address _from_compiled_entry; // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
98 // The entry point for calling both from and to compiled code is
99 // "_code->entry_point()". Because of tiered compilation and de-opt, this
100 // field can come and go. It can transition from null to not-null at any
101 // time (whenever a compile completes). It can transition from not-null to
102 // null only at safepoints (because of a de-opt).
103 nmethod* volatile _code; // Points to the corresponding piece of native code
104 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
105
106 nmethod* _preload_code; // preloaded AOT code
107 AOTCodeEntry* _aot_code_entry; // AOT Code Cache entry for pre-loading code
108
109 // Constructor
110 Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name);
111 public:
112
113 static Method* allocate(ClassLoaderData* loader_data,
114 int byte_code_size,
115 AccessFlags access_flags,
116 InlineTableSizes* sizes,
117 ConstMethod::MethodType method_type,
118 Symbol* name,
119 TRAPS);
120
121 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
122 Method(){}
123
124 virtual bool is_method() const { return true; }
125
126 #if INCLUDE_CDS
127 void remove_unshareable_info();
128 void restore_unshareable_info(TRAPS);
129 static void restore_archived_method_handle_intrinsic(methodHandle m, TRAPS);
130 #endif
131
132 // accessors for instance variables
133
134 ConstMethod* constMethod() const { return _constMethod; }
135 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
136
137
138 static address make_adapters(const methodHandle& mh, TRAPS);
139 address from_compiled_entry() const;
140 address from_interpreted_entry() const;
141
142 // access flag
143 AccessFlags access_flags() const { return _access_flags; }
144 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
145
146 // name
147 Symbol* name() const { return constants()->symbol_at(name_index()); }
148 u2 name_index() const { return constMethod()->name_index(); }
149 void set_name_index(int index) { constMethod()->set_name_index(index); }
150
151 // signature
152 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
153 u2 signature_index() const { return constMethod()->signature_index(); }
154 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
155
156 // generics support
157 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : nullptr); }
158 u2 generic_signature_index() const { return constMethod()->generic_signature_index(); }
159
160 // annotations support
161 AnnotationArray* annotations() const {
162 return constMethod()->method_annotations();
163 }
164 AnnotationArray* parameter_annotations() const {
165 return constMethod()->parameter_annotations();
166 }
167 AnnotationArray* annotation_default() const {
168 return constMethod()->default_annotations();
169 }
170 AnnotationArray* type_annotations() const {
171 return constMethod()->type_annotations();
172 }
173
174 // Helper routine: get klass name + "." + method name + signature as
175 // C string, for the purpose of providing more useful
176 // fatal error handling. The string is allocated in resource
177 // area if a buffer is not provided by the caller.
178 char* name_and_sig_as_C_string() const;
179 char* name_and_sig_as_C_string(char* buf, int size) const;
180
181 // Static routine in the situations we don't have a Method*
182 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
183 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
184
185 // Get return type + klass name + "." + method name + ( parameters types )
186 // as a C string or print it to an outputStream.
187 // This is to be used to assemble strings passed to Java, so that
188 // the text more resembles Java code. Used in exception messages.
189 // Memory is allocated in the resource area; the caller needs
190 // a ResourceMark.
191 const char* external_name() const;
192 void print_external_name(outputStream *os) const;
193
194 static const char* external_name( Klass* klass, Symbol* method_name, Symbol* signature);
195 static void print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature);
196
197 Bytecodes::Code java_code_at(int bci) const {
198 return Bytecodes::java_code_at(this, bcp_from(bci));
199 }
200 Bytecodes::Code code_at(int bci) const {
201 return Bytecodes::code_at(this, bcp_from(bci));
202 }
203
204 // JVMTI breakpoints
205 #if !INCLUDE_JVMTI
206 Bytecodes::Code orig_bytecode_at(int bci) const {
207 ShouldNotReachHere();
208 return Bytecodes::_shouldnotreachhere;
209 }
210 void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
211 ShouldNotReachHere();
212 };
213 u2 number_of_breakpoints() const {return 0;}
214 #else // !INCLUDE_JVMTI
215 Bytecodes::Code orig_bytecode_at(int bci) const;
216 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
217 void set_breakpoint(int bci);
218 void clear_breakpoint(int bci);
219 void clear_all_breakpoints();
220 // Tracking number of breakpoints, for fullspeed debugging.
221 // Only mutated by VM thread.
222 inline u2 number_of_breakpoints() const;
223 inline void incr_number_of_breakpoints(Thread* current);
224 inline void decr_number_of_breakpoints(Thread* current);
225 // Initialization only
226 inline void clear_number_of_breakpoints();
227 #endif // !INCLUDE_JVMTI
228
229 // index into InstanceKlass methods() array
230 // note: also used by jfr
231 u2 method_idnum() const { return constMethod()->method_idnum(); }
232 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
233
234 u2 orig_method_idnum() const { return constMethod()->orig_method_idnum(); }
235 void set_orig_method_idnum(u2 idnum) { constMethod()->set_orig_method_idnum(idnum); }
236
237 // code size
238 u2 code_size() const { return constMethod()->code_size(); }
239
240 // method size in words
241 int method_size() const { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }
242
243 // constant pool for Klass* holding this method
244 ConstantPool* constants() const { return constMethod()->constants(); }
245 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
246
247 // max stack
248 // return original max stack size for method verification
249 u2 verifier_max_stack() const { return constMethod()->max_stack(); }
250 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
251 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
252
253 // max locals
254 u2 max_locals() const { return constMethod()->max_locals(); }
255 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
256
257 void set_deprecated() { constMethod()->set_deprecated(); }
258 bool deprecated() const { return constMethod()->deprecated(); }
259
260 void set_deprecated_for_removal() { constMethod()->set_deprecated_for_removal(); }
261 bool deprecated_for_removal() const { return constMethod()->deprecated_for_removal(); }
262
263 inline int highest_comp_level() const;
264 void set_highest_comp_level(int level);
265 int highest_osr_comp_level() const;
266 void set_highest_osr_comp_level(int level);
267
268 #if COMPILER2_OR_JVMCI
269 // Count of times method was exited via exception while interpreting
270 inline void interpreter_throwout_increment(Thread* current);
271 #endif
272
273 inline int interpreter_throwout_count() const;
274
275 u2 size_of_parameters() const { return constMethod()->size_of_parameters(); }
276
277 bool has_stackmap_table() const {
278 return constMethod()->has_stackmap_table();
279 }
280
281 Array<u1>* stackmap_data() const {
282 return constMethod()->stackmap_data();
283 }
284
285 void set_stackmap_data(Array<u1>* sd) {
286 constMethod()->set_stackmap_data(sd);
287 }
288
289 // exception handler table
290 bool has_exception_handler() const
291 { return constMethod()->has_exception_table(); }
292 u2 exception_table_length() const
293 { return constMethod()->exception_table_length(); }
294 ExceptionTableElement* exception_table_start() const
295 { return constMethod()->exception_table_start(); }
296
297 // Finds the first entry point bci of an exception handler for an
298 // exception of klass ex_klass thrown at throw_bci. A value of null
299 // for ex_klass indicates that the exception klass is not known; in
300 // this case it matches any constraint class. Returns -1 if the
301 // exception cannot be handled in this method. The handler
302 // constraint classes are loaded if necessary. Note that this may
303 // throw an exception if loading of the constraint classes causes
304 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
305 // If an exception is thrown, returns the bci of the
306 // exception handler which caused the exception to be thrown, which
307 // is needed for proper retries. See, for example,
308 // InterpreterRuntime::exception_handler_for_exception.
309 static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
310
311 static bool register_native(Klass* k,
312 Symbol* name,
313 Symbol* signature,
314 address entry,
315 TRAPS);
316
317 // method data access
318 MethodData* method_data() const {
319 return _method_data;
320 }
321 void set_method_data(MethodData* data);
322
323 MethodTrainingData* training_data_or_null() const;
324 bool init_training_data(MethodTrainingData* td);
325
326 // mark an exception handler as entered (used to prune dead catch blocks in C2)
327 void set_exception_handler_entered(int handler_bci);
328
329 MethodCounters* method_counters() const {
330 return _method_counters;
331 }
332
333 void clear_method_counters() {
334 _method_counters = nullptr;
335 }
336
337 bool init_method_counters(MethodCounters* counters);
338
339 inline int prev_event_count() const;
340 inline void set_prev_event_count(int count);
341 inline jlong prev_time() const;
342 inline void set_prev_time(jlong time);
343 inline float rate() const;
344 inline void set_rate(float rate);
345
346 inline int invocation_count() const;
347 inline int backedge_count() const;
348
349 bool was_executed_more_than(int n);
350 bool was_never_executed() { return !was_executed_more_than(0); }
351
352 static void build_profiling_method_data(const methodHandle& method, TRAPS);
353 static bool install_training_method_data(const methodHandle& method);
354 static MethodCounters* build_method_counters(Thread* current, Method* m);
355
356 inline int interpreter_invocation_count() const;
357
358 #ifndef PRODUCT
359 int64_t compiled_invocation_count() const { return _compiled_invocation_count;}
360 void set_compiled_invocation_count(int count) { _compiled_invocation_count = (int64_t)count; }
361 #else
362 // for PrintMethodData in a product build
363 int64_t compiled_invocation_count() const { return 0; }
364 #endif // not PRODUCT
365
366 // nmethod/verified compiler entry
367 address verified_code_entry();
368 bool check_code() const; // Not inline to avoid circular ref
369 nmethod* code() const;
370
371 // Locks NMethodState_lock if not held.
372 void unlink_code(nmethod *compare);
373 // Locks NMethodState_lock if not held.
374 void unlink_code();
375
376 private:
377 // Either called with NMethodState_lock held or from constructor.
378 void clear_code();
379
380 void clear_method_data() {
381 _method_data = nullptr;
382 }
383
384 public:
385 static void set_code(const methodHandle& mh, nmethod* code);
386 void set_adapter_entry(AdapterHandlerEntry* adapter) {
387 _adapter = adapter;
388 }
389 void set_from_compiled_entry(address entry) {
390 _from_compiled_entry = entry;
391 }
392
393 void set_preload_code(nmethod* code) {
394 _preload_code = code;
395 }
396 void set_aot_code_entry(AOTCodeEntry* entry) {
397 _aot_code_entry = entry;
398 }
399 AOTCodeEntry* aot_code_entry() const {
400 return _aot_code_entry;
401 }
402
403 address get_i2c_entry();
404 address get_c2i_entry();
405 address get_c2i_unverified_entry();
406 address get_c2i_no_clinit_check_entry();
407 AdapterHandlerEntry* adapter() const {
408 return _adapter;
409 }
410 // setup entry points
411 void link_method(const methodHandle& method, TRAPS);
412 // clear entry points. Used by sharing code during dump time
413 void unlink_method() NOT_CDS_RETURN;
414 void remove_unshareable_flags() NOT_CDS_RETURN;
415
416 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
417 virtual MetaspaceObj::Type type() const { return MethodType; }
418
419 // vtable index
420 enum VtableIndexFlag {
421 // Valid vtable indexes are non-negative (>= 0).
422 // These few negative values are used as sentinels.
423 itable_index_max = -10, // first itable index, growing downward
424 pending_itable_index = -9, // itable index will be assigned
425 invalid_vtable_index = -4, // distinct from any valid vtable index
426 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
427 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
428 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
429 };
430 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
431 bool has_vtable_index() const { return _vtable_index >= 0; }
432 int vtable_index() const { return _vtable_index; }
433 void set_vtable_index(int index);
434 DEBUG_ONLY(bool valid_itable_index() const { return _vtable_index <= pending_itable_index; })
435 bool has_itable_index() const { return _vtable_index <= itable_index_max; }
436 int itable_index() const { assert(valid_itable_index(), "");
437 return itable_index_max - _vtable_index; }
438 void set_itable_index(int index);
439
440 // interpreter entry
441 address interpreter_entry() const { return _i2i_entry; }
442 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
443 void set_interpreter_entry(address entry) {
444 if (_i2i_entry != entry) {
445 _i2i_entry = entry;
446 }
447 if (_from_interpreted_entry != entry) {
448 _from_interpreted_entry = entry;
449 }
450 }
451
452 // native function (used for native methods only)
453 enum {
454 native_bind_event_is_interesting = true
455 };
456 address native_function() const { return *(native_function_addr()); }
457
458 // Must specify a real function (not null).
459 // Use clear_native_function() to unregister.
460 void set_native_function(address function, bool post_event_flag);
461 bool has_native_function() const;
462 void clear_native_function();
463
464 // signature handler (used for native methods only)
465 address signature_handler() const { return *(signature_handler_addr()); }
466 void set_signature_handler(address handler);
467
468 // Interpreter oopmap support.
469 // If handle is already available, call with it for better performance.
470 void mask_for(int bci, InterpreterOopMap* mask);
471 void mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask);
472
473 // operations on invocation counter
474 void print_invocation_count(outputStream* st);
475
476 // byte codes
477 void set_code(address code) { return constMethod()->set_code(code); }
478 address code_base() const { return constMethod()->code_base(); }
479 bool contains(address bcp) const { return constMethod()->contains(bcp); }
480
481 // prints byte codes
482 void print_codes(int flags = 0) const { print_codes_on(tty, flags); }
483 void print_codes_on(outputStream* st, int flags = 0) const;
484 void print_codes_on(int from, int to, outputStream* st, int flags = 0) const;
485
486 // method parameters
487 bool has_method_parameters() const
488 { return constMethod()->has_method_parameters(); }
489 int method_parameters_length() const
490 { return constMethod()->method_parameters_length(); }
491 MethodParametersElement* method_parameters_start() const
492 { return constMethod()->method_parameters_start(); }
493
494 // checked exceptions
495 u2 checked_exceptions_length() const
496 { return constMethod()->checked_exceptions_length(); }
497 CheckedExceptionElement* checked_exceptions_start() const
498 { return constMethod()->checked_exceptions_start(); }
499
500 // localvariable table
501 bool has_localvariable_table() const
502 { return constMethod()->has_localvariable_table(); }
503 u2 localvariable_table_length() const
504 { return constMethod()->localvariable_table_length(); }
505 LocalVariableTableElement* localvariable_table_start() const
506 { return constMethod()->localvariable_table_start(); }
507
508 bool has_linenumber_table() const
509 { return constMethod()->has_linenumber_table(); }
510 u_char* compressed_linenumber_table() const
511 { return constMethod()->compressed_linenumber_table(); }
512
513 // method holder (the Klass* holding this method)
514 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
515
516 Symbol* klass_name() const; // returns the name of the method holder
517 BasicType result_type() const { return constMethod()->result_type(); }
518 bool is_returning_oop() const { BasicType r = result_type(); return is_reference_type(r); }
519 bool is_returning_fp() const { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }
520
521 // Checked exceptions thrown by this method (resolved to mirrors)
522 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
523
524 // Access flags
525 bool is_public() const { return access_flags().is_public(); }
526 bool is_private() const { return access_flags().is_private(); }
527 bool is_protected() const { return access_flags().is_protected(); }
528 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
529 bool is_static() const { return access_flags().is_static(); }
530 bool is_final() const { return access_flags().is_final(); }
531 bool is_synchronized() const { return access_flags().is_synchronized();}
532 bool is_native() const { return access_flags().is_native(); }
533 bool is_abstract() const { return access_flags().is_abstract(); }
534 bool is_synthetic() const { return access_flags().is_synthetic(); }
535
536 // returns true if contains only return operation
537 bool is_empty_method() const;
538
539 // returns true if this is a vanilla constructor
540 bool is_vanilla_constructor() const;
541
542 // checks method and its method holder
543 bool is_final_method() const;
544 bool is_final_method(AccessFlags class_access_flags) const;
545 // interface method declared with 'default' - excludes private interface methods
546 bool is_default_method() const;
547
548 // true if method needs no dynamic dispatch (final and/or no vtable entry)
549 bool can_be_statically_bound() const;
550 bool can_be_statically_bound(InstanceKlass* context) const;
551 bool can_be_statically_bound(AccessFlags class_access_flags) const;
552
553 // true if method can omit stack trace in throw in compiled code.
554 bool can_omit_stack_trace();
555
556 // Flags getting and setting.
557 #define M_STATUS_GET_SET(name, ignore) \
558 bool name() const { return _flags.name(); } \
559 void set_##name(bool x) { _flags.set_##name(x); } \
560 void set_##name() { _flags.set_##name(true); }
561 M_STATUS_DO(M_STATUS_GET_SET)
562 #undef M_STATUS_GET_SET
563
564 // returns true if the method has any backward branches.
565 bool has_loops() {
566 return has_loops_flag_init() ? has_loops_flag() : compute_has_loops_flag();
567 };
568
569 bool compute_has_loops_flag();
570 bool set_has_loops() {
571 // set both the flags and that it's been initialized.
572 set_has_loops_flag();
573 set_has_loops_flag_init();
574 return true;
575 }
576
577 // returns true if the method has any monitors.
578 bool has_monitors() const { return is_synchronized() || has_monitor_bytecodes(); }
579
580 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
581 // properly nest in the method. It might return false, even though they actually nest properly, since the info.
582 // has not been computed yet.
583 bool guaranteed_monitor_matching() const { return monitor_matching(); }
584 void set_guaranteed_monitor_matching() { set_monitor_matching(); }
585
586 // returns true if the method is an accessor function (setter/getter).
587 bool is_accessor() const;
588
589 // returns true if the method is a getter
590 bool is_getter() const;
591
592 // returns true if the method is a setter
593 bool is_setter() const;
594
595 // returns true if the method does nothing but return a constant of primitive type
596 bool is_constant_getter() const;
597
598 // returns true if the method is static OR if the classfile version < 51
599 bool has_valid_initializer_flags() const;
600
601 // returns true if the method name is <clinit> and the method has
602 // valid static initializer flags.
603 bool is_static_initializer() const;
604
605 // returns true if the method name is <init>
606 bool is_object_initializer() const;
607
608 // returns true if the method name is wait0
609 bool is_object_wait0() const;
610
611 // compiled code support
612 // NOTE: code() is inherently racy as deopt can be clearing code
613 // simultaneously. Use with caution.
614 bool has_compiled_code() const;
615
616 bool needs_clinit_barrier() const;
617 bool code_has_clinit_barriers() const;
618
619 // sizing
620 static int header_size() {
621 return align_up((int)sizeof(Method), wordSize) / wordSize;
622 }
623 static int size(bool is_native);
624 int size() const { return method_size(); }
625 void log_touched(Thread* current);
626 static void print_touched_methods(outputStream* out);
627
628 // interpreter support
629 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
630 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
631 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
632 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
633
634 static ByteSize method_counters_offset() {
635 return byte_offset_of(Method, _method_counters);
636 }
637 #ifndef PRODUCT
638 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
639 #endif // not PRODUCT
640 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
641 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
642 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
643 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
644 static ByteSize itable_index_offset() { return byte_offset_of(Method, _vtable_index ); }
645
646 // for code generation
647 static ByteSize method_data_offset() { return byte_offset_of(Method, _method_data); }
648 static ByteSize intrinsic_id_offset() { return byte_offset_of(Method, _intrinsic_id); }
649 static int intrinsic_id_size_in_bytes() { return sizeof(u2); }
650
651 // Static methods that are used to implement member methods where an exposed this pointer
652 // is needed due to possible GCs
653 static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
654
655 // Returns the byte code index from the byte code pointer
656 int bci_from(address bcp) const;
657 address bcp_from(int bci) const;
658 address bcp_from(address bcp) const;
659 int validate_bci_from_bcp(address bcp) const;
660 int validate_bci(int bci) const;
661
662 // Returns the line number for a bci if debugging information for the method is prowided,
663 // -1 is returned otherwise.
664 int line_number_from_bci(int bci) const;
665
666 // Reflection support
667 bool is_overridden_in(Klass* k) const;
668
669 // Stack walking support
670 bool is_ignored_by_security_stack_walk() const;
671
672 // JSR 292 support
673 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
674 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
675 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
676 static methodHandle make_method_handle_intrinsic(vmIntrinsicID iid, // _invokeBasic, _linkToVirtual
677 Symbol* signature, //anything at all
678 TRAPS);
679 // Some special methods don't need to be findable by nmethod iterators and are permanent.
680 bool can_be_allocated_in_NonNMethod_space() const { return is_method_handle_intrinsic(); }
681
682 // Continuation
683 inline bool is_continuation_enter_intrinsic() const;
684 inline bool is_continuation_yield_intrinsic() const;
685 inline bool is_continuation_native_intrinsic() const;
686 inline bool is_special_native_intrinsic() const;
687
688 static Klass* check_non_bcp_klass(Klass* klass);
689
690 enum {
691 // How many extra stack entries for invokedynamic
692 extra_stack_entries_for_jsr292 = 1
693 };
694
695 // this operates only on invoke methods:
696 // presize interpreter frames for extra interpreter stack entries, if needed
697 // Account for the extra appendix argument for invokehandle/invokedynamic
698 static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
699 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize
700
701 // RedefineClasses() support:
702 bool on_stack() const { return on_stack_flag(); }
703 void set_on_stack(const bool value);
704
705 void record_gc_epoch();
706
707 // see the definition in Method*.cpp for the gory details
708 bool should_not_be_cached() const;
709
710 // Rewriting support
711 static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
712 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
713
714 // jmethodID handling
715 // Because the useful life-span of a jmethodID cannot be determined,
716 // once created they are never reclaimed. The methods to which they refer,
717 // however, can be GC'ed away if the class is unloaded or if the method is
718 // made obsolete or deleted -- in these cases, the jmethodID
719 // refers to null (as is the case for any weak reference).
720 static jmethodID make_jmethod_id(ClassLoaderData* cld, Method* mh);
721
722 // Ensure there is enough capacity in the internal tracking data
723 // structures to hold the number of jmethodIDs you plan to generate.
724 // This saves substantial time doing allocations.
725 static void ensure_jmethod_ids(ClassLoaderData* cld, int capacity);
726
727 // Use resolve_jmethod_id() in situations where the caller is expected
728 // to provide a valid jmethodID; the only sanity checks are in asserts;
729 // result guaranteed not to be null.
730 inline static Method* resolve_jmethod_id(jmethodID mid) {
731 assert(mid != nullptr, "JNI method id should not be null");
732 return *((Method**)mid);
733 }
734
735 // Use checked_resolve_jmethod_id() in situations where the caller
736 // should provide a valid jmethodID, but might not. Null is returned
737 // when the jmethodID does not refer to a valid method.
738 static Method* checked_resolve_jmethod_id(jmethodID mid);
739
740 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
741 static bool is_method_id(jmethodID mid);
742
743 // Clear methods
744 static void clear_jmethod_ids(ClassLoaderData* loader_data);
745 void clear_jmethod_id();
746 static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
747
748 // Get this method's jmethodID -- allocate if it doesn't exist
749 jmethodID jmethod_id();
750
751 // Lookup the jmethodID for this method. Return null if not found.
752 // NOTE that this function can be called from a signal handler
753 // (see AsyncGetCallTrace support for Forte Analyzer) and this
754 // needs to be async-safe. No allocation should be done and
755 // so handles are not used to avoid deadlock.
756 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
757
758 // Support for inlining of intrinsic methods
759 vmIntrinsicID intrinsic_id() const { return (vmIntrinsicID) _intrinsic_id; }
760 void set_intrinsic_id(vmIntrinsicID id) { _intrinsic_id = (u2) id; }
761
762 // Helper routines for intrinsic_id() and vmIntrinsics::method().
763 void init_intrinsic_id(vmSymbolID klass_id); // updates from _none if a match
764 static vmSymbolID klass_id_for_intrinsics(const Klass* holder);
765
766 bool caller_sensitive() const { return constMethod()->caller_sensitive(); }
767 void set_caller_sensitive() { constMethod()->set_caller_sensitive(); }
768
769 bool changes_current_thread() const { return constMethod()->changes_current_thread(); }
770 void set_changes_current_thread() { constMethod()->set_changes_current_thread(); }
771
772 bool jvmti_hide_events() const { return constMethod()->jvmti_hide_events(); }
773 void set_jvmti_hide_events() { constMethod()->set_jvmti_hide_events(); }
774
775 bool jvmti_mount_transition() const { return constMethod()->jvmti_mount_transition(); }
776 void set_jvmti_mount_transition() { constMethod()->set_jvmti_mount_transition(); }
777
778 bool is_hidden() const { return constMethod()->is_hidden(); }
779 void set_is_hidden() { constMethod()->set_is_hidden(); }
780
781 bool is_scoped() const { return constMethod()->is_scoped(); }
782 void set_scoped() { constMethod()->set_is_scoped(); }
783
784 bool intrinsic_candidate() const { return constMethod()->intrinsic_candidate(); }
785 void set_intrinsic_candidate() { constMethod()->set_intrinsic_candidate(); }
786
787 bool has_injected_profile() const { return constMethod()->has_injected_profile(); }
788 void set_has_injected_profile() { constMethod()->set_has_injected_profile(); }
789
790 bool has_reserved_stack_access() const { return constMethod()->reserved_stack_access(); }
791 void set_has_reserved_stack_access() { constMethod()->set_reserved_stack_access(); }
792
793 JFR_ONLY(DEFINE_TRACE_FLAG_ACCESSOR;)
794
795 ConstMethod::MethodType method_type() const {
796 return _constMethod->method_type();
797 }
798 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
799
800 // On-stack replacement support
801 bool has_osr_nmethod(int level, bool match_level) {
802 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != nullptr;
803 }
804
805 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
806 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
807 }
808
809 // Find if klass for method is loaded
810 bool is_klass_loaded_by_klass_index(int klass_index) const;
811 bool is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved = false) const;
812
813 // Indicates whether compilation failed earlier for this method, or
814 // whether it is not compilable for another reason like having a
815 // breakpoint set in it.
816 bool is_not_compilable(int comp_level = CompLevel_any) const;
817 void set_not_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
818 void set_not_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
819 set_not_compilable(reason, comp_level, false);
820 }
821 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
822 void set_not_osr_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
823 void set_not_osr_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
824 set_not_osr_compilable(reason, comp_level, false);
825 }
826 bool is_always_compilable() const;
827
828 private:
829 void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
830
831 public:
832 MethodCounters* get_method_counters(Thread* current) {
833 if (_method_counters == nullptr) {
834 build_method_counters(current, this);
835 }
836 return _method_counters;
837 }
838
839 void clear_is_not_c1_compilable() { set_is_not_c1_compilable(false); }
840 void clear_is_not_c2_compilable() { set_is_not_c2_compilable(false); }
841 void clear_is_not_c2_osr_compilable() { set_is_not_c2_osr_compilable(false); }
842
843 // not_c1_osr_compilable == not_c1_compilable
844 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); }
845 void set_is_not_c1_osr_compilable() { set_is_not_c1_compilable(); }
846 void clear_is_not_c1_osr_compilable() { clear_is_not_c1_compilable(); }
847
848 // Background compilation support
849 void clear_queued_for_compilation() { set_queued_for_compilation(false); }
850
851 // Resolve all classes in signature, return 'true' if successful
852 static bool load_signature_classes(const methodHandle& m, TRAPS);
853
854 // Printing
855 void print_short_name(outputStream* st = tty) const; // prints as klassname::methodname; Exposed so field engineers can debug VM
856 #if INCLUDE_JVMTI
857 void print_name(outputStream* st = tty) const; // prints as "virtual void foo(int)"; exposed for -Xlog:redefine+class
858 #else
859 void print_name(outputStream* st = tty) const PRODUCT_RETURN; // prints as "virtual void foo(int)"
860 #endif
861
862 typedef int (*method_comparator_func)(Method* a, Method* b);
863
864 // Helper routine used for method sorting
865 static void sort_methods(Array<Method*>* methods, bool set_idnums = true, method_comparator_func func = nullptr);
866
867 // Deallocation function for redefine classes or if an error occurs
868 void deallocate_contents(ClassLoaderData* loader_data);
869
870 void release_C_heap_structures();
871
872 Method* get_new_method() const {
873 InstanceKlass* holder = method_holder();
874 Method* new_method = holder->method_with_idnum(orig_method_idnum());
875
876 assert(new_method != nullptr, "method_with_idnum() should not be null");
877 assert(this != new_method, "sanity check");
878 return new_method;
879 }
880
881 // Printing
882 #ifndef PRODUCT
883 void print_on(outputStream* st) const;
884 #endif
885 void print_value_on(outputStream* st) const;
886 void print_linkage_flags(outputStream* st) PRODUCT_RETURN;
887
888 const char* internal_name() const { return "{method}"; }
889
890 // Check for valid method pointer
891 static bool has_method_vptr(const void* ptr);
892 static bool is_valid_method(const Method* m);
893
894 // Verify
895 void verify() { verify_on(tty); }
896 void verify_on(outputStream* st);
897
898 private:
899
900 // Inlined elements
901 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
902 address* signature_handler_addr() const { return native_function_addr() + 1; }
903 };
904
905
906 // Utility class for compressing line number tables
907
908 class CompressedLineNumberWriteStream: public CompressedWriteStream {
909 private:
910 int _bci;
911 int _line;
912 public:
913 // Constructor
914 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
915 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
916
917 // Write (bci, line number) pair to stream
918 void write_pair_regular(int bci_delta, int line_delta);
919
920 // If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
921 // we save it as one byte, otherwise we write a 0xFF escape character
922 // and use regular compression. 0x0 is used as end-of-stream terminator.
923 void write_pair_inline(int bci, int line);
924
925 void write_pair(int bci, int line);
926
927 // Write end-of-stream marker
928 void write_terminator() { write_byte(0); }
929 };
930
931
932 // Utility class for decompressing line number tables
933
934 class CompressedLineNumberReadStream: public CompressedReadStream {
935 private:
936 int _bci;
937 int _line;
938 public:
939 // Constructor
940 CompressedLineNumberReadStream(u_char* buffer);
941 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
942 bool read_pair();
943 // Accessing bci and line number (after calling read_pair)
944 int bci() const { return _bci; }
945 int line() const { return _line; }
946 };
947
948
949 #if INCLUDE_JVMTI
950
951 /// Fast Breakpoints.
952
953 // If this structure gets more complicated (because bpts get numerous),
954 // move it into its own header.
955
956 // There is presently no provision for concurrent access
957 // to breakpoint lists, which is only OK for JVMTI because
958 // breakpoints are written only at safepoints, and are read
959 // concurrently only outside of safepoints.
960
961 class BreakpointInfo : public CHeapObj<mtClass> {
962 friend class VMStructs;
963 private:
964 Bytecodes::Code _orig_bytecode;
965 int _bci;
966 u2 _name_index; // of method
967 u2 _signature_index; // of method
968 BreakpointInfo* _next; // simple storage allocation
969
970 public:
971 BreakpointInfo(Method* m, int bci);
972
973 // accessors
974 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
975 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
976 int bci() { return _bci; }
977
978 BreakpointInfo* next() const { return _next; }
979 void set_next(BreakpointInfo* n) { _next = n; }
980
981 // helps for searchers
982 bool match(const Method* m, int bci) {
983 return bci == _bci && match(m);
984 }
985
986 bool match(const Method* m) {
987 return _name_index == m->name_index() &&
988 _signature_index == m->signature_index();
989 }
990
991 void set(Method* method);
992 void clear(Method* method);
993 };
994
995 #endif // INCLUDE_JVMTI
996
997 // Utility class for access exception handlers
998 class ExceptionTable : public StackObj {
999 private:
1000 ExceptionTableElement* _table;
1001 u2 _length;
1002
1003 public:
1004 ExceptionTable(const Method* m) {
1005 if (m->has_exception_handler()) {
1006 _table = m->exception_table_start();
1007 _length = m->exception_table_length();
1008 } else {
1009 _table = nullptr;
1010 _length = 0;
1011 }
1012 }
1013
1014 u2 length() const {
1015 return _length;
1016 }
1017
1018 u2 start_pc(int idx) const {
1019 assert(idx < _length, "out of bounds");
1020 return _table[idx].start_pc;
1021 }
1022
1023 void set_start_pc(int idx, u2 value) {
1024 assert(idx < _length, "out of bounds");
1025 _table[idx].start_pc = value;
1026 }
1027
1028 u2 end_pc(int idx) const {
1029 assert(idx < _length, "out of bounds");
1030 return _table[idx].end_pc;
1031 }
1032
1033 void set_end_pc(int idx, u2 value) {
1034 assert(idx < _length, "out of bounds");
1035 _table[idx].end_pc = value;
1036 }
1037
1038 u2 handler_pc(int idx) const {
1039 assert(idx < _length, "out of bounds");
1040 return _table[idx].handler_pc;
1041 }
1042
1043 void set_handler_pc(int idx, u2 value) {
1044 assert(idx < _length, "out of bounds");
1045 _table[idx].handler_pc = value;
1046 }
1047
1048 u2 catch_type_index(int idx) const {
1049 assert(idx < _length, "out of bounds");
1050 return _table[idx].catch_type_index;
1051 }
1052
1053 void set_catch_type_index(int idx, u2 value) {
1054 assert(idx < _length, "out of bounds");
1055 _table[idx].catch_type_index = value;
1056 }
1057 };
1058
1059 #endif // SHARE_OOPS_METHOD_HPP