1 /*
2 * Copyright (c) 1997, 2024, 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/methodFlags.hpp"
33 #include "oops/instanceKlass.hpp"
34 #include "oops/oop.hpp"
35 #include "oops/typeArrayOop.hpp"
36 #include "utilities/accessFlags.hpp"
37 #include "utilities/align.hpp"
38 #include "utilities/growableArray.hpp"
39 #include "utilities/macros.hpp"
40 #include "utilities/vmEnums.hpp"
41 #if INCLUDE_JFR
42 #include "jfr/support/jfrTraceIdExtension.hpp"
43 #endif
44
45
46 // A Method represents a Java method.
47 //
48 // Note that most applications load thousands of methods, so keeping the size of this
49 // class small has a big impact on footprint.
50 //
51 // Note that native_function and signature_handler have to be at fixed offsets
52 // (required by the interpreter)
53 //
54 // Method embedded field layout (after declared fields):
55 // [EMBEDDED native_function (present only if native) ]
56 // [EMBEDDED signature_handler (present only if native) ]
57
58 class CheckedExceptionElement;
59 class LocalVariableTableElement;
60 class AdapterHandlerEntry;
61 class MethodData;
62 class MethodCounters;
63 class ConstMethod;
64 class InlineTableSizes;
65 class CompiledMethod;
66 class InterpreterOopMap;
67
68 class Method : public Metadata {
69 friend class VMStructs;
70 friend class JVMCIVMStructs;
71 friend class MethodTest;
72 private:
73 // If you add a new field that points to any metaspace object, you
74 // must add this field to Method::metaspace_pointers_do().
75 ConstMethod* _constMethod; // Method read-only data.
76 MethodData* _method_data;
77 MethodCounters* _method_counters;
78 AdapterHandlerEntry* _adapter;
79 AccessFlags _access_flags; // Access flags
80 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
81 MethodFlags _flags;
82
83 u2 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
84
85 JFR_ONLY(DEFINE_TRACE_FLAG;)
86
87 #ifndef PRODUCT
88 int64_t _compiled_invocation_count;
89
90 Symbol* _name;
91 #endif
92 // Entry point for calling both from and to the interpreter.
93 address _i2i_entry; // All-args-on-stack calling convention
94 // Entry point for calling from compiled code, to compiled code if it exists
95 // or else the interpreter.
96 volatile address _from_compiled_entry; // Cache of: _code ? _code->verified_entry_point() : _adapter->c2i_entry()
97 volatile address _from_compiled_inline_ro_entry; // Cache of: _code ? _code->verified_inline_ro_entry_point() : _adapter->c2i_inline_ro_entry()
98 volatile address _from_compiled_inline_entry; // Cache of: _code ? _code->verified_inline_entry_point() : _adapter->c2i_inline_entry()
99 // The entry point for calling both from and to compiled code is
100 // "_code->entry_point()". Because of tiered compilation and de-opt, this
101 // field can come and go. It can transition from null to not-null at any
102 // time (whenever a compile completes). It can transition from not-null to
103 // null only at safepoints (because of a de-opt).
104 CompiledMethod* volatile _code; // Points to the corresponding piece of native code
105 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
106
107 // Constructor
108 Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name);
109 public:
110
111 static Method* allocate(ClassLoaderData* loader_data,
112 int byte_code_size,
113 AccessFlags access_flags,
114 InlineTableSizes* sizes,
115 ConstMethod::MethodType method_type,
116 Symbol* name,
117 TRAPS);
118
119 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
120 Method(){}
121
122 virtual bool is_method() const { return true; }
123
124 #if INCLUDE_CDS
125 void remove_unshareable_info();
126 void restore_unshareable_info(TRAPS);
127 #endif
128
129 // accessors for instance variables
130
131 ConstMethod* constMethod() const { return _constMethod; }
132 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
133
134
135 static address make_adapters(const methodHandle& mh, TRAPS);
136 address from_compiled_entry() const;
137 address from_compiled_inline_ro_entry() const;
138 address from_compiled_inline_entry() const;
139 address from_interpreted_entry() const;
140
141 // access flag
142 AccessFlags access_flags() const { return _access_flags; }
143 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
144
145 // name
146 Symbol* name() const { return constants()->symbol_at(name_index()); }
147 u2 name_index() const { return constMethod()->name_index(); }
148 void set_name_index(int index) { constMethod()->set_name_index(index); }
149
150 // signature
151 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
152 u2 signature_index() const { return constMethod()->signature_index(); }
153 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
154
155 // generics support
156 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : nullptr); }
157 u2 generic_signature_index() const { return constMethod()->generic_signature_index(); }
158
159 // annotations support
160 AnnotationArray* annotations() const {
161 return constMethod()->method_annotations();
162 }
163 AnnotationArray* parameter_annotations() const {
164 return constMethod()->parameter_annotations();
165 }
166 AnnotationArray* annotation_default() const {
167 return constMethod()->default_annotations();
168 }
169 AnnotationArray* type_annotations() const {
170 return constMethod()->type_annotations();
171 }
172
173 // Helper routine: get klass name + "." + method name + signature as
174 // C string, for the purpose of providing more useful
175 // fatal error handling. The string is allocated in resource
176 // area if a buffer is not provided by the caller.
177 char* name_and_sig_as_C_string() const;
178 char* name_and_sig_as_C_string(char* buf, int size) const;
179
180 // Static routine in the situations we don't have a Method*
181 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
182 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
183
184 // Get return type + klass name + "." + method name + ( parameters types )
185 // as a C string or print it to an outputStream.
186 // This is to be used to assemble strings passed to Java, so that
187 // the text more resembles Java code. Used in exception messages.
188 // Memory is allocated in the resource area; the caller needs
189 // a ResourceMark.
190 const char* external_name() const;
191 void print_external_name(outputStream *os) const;
192
193 static const char* external_name( Klass* klass, Symbol* method_name, Symbol* signature);
194 static void print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature);
195
196 Bytecodes::Code java_code_at(int bci) const {
197 return Bytecodes::java_code_at(this, bcp_from(bci));
198 }
199 Bytecodes::Code code_at(int bci) const {
200 return Bytecodes::code_at(this, bcp_from(bci));
201 }
202
203 // JVMTI breakpoints
204 #if !INCLUDE_JVMTI
205 Bytecodes::Code orig_bytecode_at(int bci) const {
206 ShouldNotReachHere();
207 return Bytecodes::_shouldnotreachhere;
208 }
209 void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
210 ShouldNotReachHere();
211 };
212 u2 number_of_breakpoints() const {return 0;}
213 #else // !INCLUDE_JVMTI
214 Bytecodes::Code orig_bytecode_at(int bci) const;
215 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
216 void set_breakpoint(int bci);
217 void clear_breakpoint(int bci);
218 void clear_all_breakpoints();
219 // Tracking number of breakpoints, for fullspeed debugging.
220 // Only mutated by VM thread.
221 inline u2 number_of_breakpoints() const;
222 inline void incr_number_of_breakpoints(Thread* current);
223 inline void decr_number_of_breakpoints(Thread* current);
224 // Initialization only
225 inline void clear_number_of_breakpoints();
226 #endif // !INCLUDE_JVMTI
227
228 // index into InstanceKlass methods() array
229 // note: also used by jfr
230 u2 method_idnum() const { return constMethod()->method_idnum(); }
231 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
232
233 u2 orig_method_idnum() const { return constMethod()->orig_method_idnum(); }
234 void set_orig_method_idnum(u2 idnum) { constMethod()->set_orig_method_idnum(idnum); }
235
236 // code size
237 u2 code_size() const { return constMethod()->code_size(); }
238
239 // method size in words
240 int method_size() const { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }
241
242 // constant pool for Klass* holding this method
243 ConstantPool* constants() const { return constMethod()->constants(); }
244 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
245
246 // max stack
247 // return original max stack size for method verification
248 u2 verifier_max_stack() const { return constMethod()->max_stack(); }
249 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
250 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
251
252 // max locals
253 u2 max_locals() const { return constMethod()->max_locals(); }
254 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
255
256 void set_deprecated() { constMethod()->set_deprecated(); }
257 bool deprecated() const { return constMethod()->deprecated(); }
258
259 void set_deprecated_for_removal() { constMethod()->set_deprecated_for_removal(); }
260 bool deprecated_for_removal() const { return constMethod()->deprecated_for_removal(); }
261
262 int highest_comp_level() const;
263 void set_highest_comp_level(int level);
264 int highest_osr_comp_level() const;
265 void set_highest_osr_comp_level(int level);
266
267 #if COMPILER2_OR_JVMCI
268 // Count of times method was exited via exception while interpreting
269 inline void interpreter_throwout_increment(Thread* current);
270 #endif
271
272 inline int interpreter_throwout_count() const;
273
274 u2 size_of_parameters() const { return constMethod()->size_of_parameters(); }
275
276 bool has_stackmap_table() const {
277 return constMethod()->has_stackmap_table();
278 }
279
280 Array<u1>* stackmap_data() const {
281 return constMethod()->stackmap_data();
282 }
283
284 void set_stackmap_data(Array<u1>* sd) {
285 constMethod()->set_stackmap_data(sd);
286 }
287
288 // exception handler table
289 bool has_exception_handler() const
290 { return constMethod()->has_exception_table(); }
291 u2 exception_table_length() const
292 { return constMethod()->exception_table_length(); }
293 ExceptionTableElement* exception_table_start() const
294 { return constMethod()->exception_table_start(); }
295
296 // Finds the first entry point bci of an exception handler for an
297 // exception of klass ex_klass thrown at throw_bci. A value of null
298 // for ex_klass indicates that the exception klass is not known; in
299 // this case it matches any constraint class. Returns -1 if the
300 // exception cannot be handled in this method. The handler
301 // constraint classes are loaded if necessary. Note that this may
302 // throw an exception if loading of the constraint classes causes
303 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
304 // If an exception is thrown, returns the bci of the
305 // exception handler which caused the exception to be thrown, which
306 // is needed for proper retries. See, for example,
307 // InterpreterRuntime::exception_handler_for_exception.
308 static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
309
310 static bool register_native(Klass* k,
311 Symbol* name,
312 Symbol* signature,
313 address entry,
314 TRAPS);
315
316 // method data access
317 MethodData* method_data() const {
318 return _method_data;
319 }
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 int invocation_count() const;
342 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
349 static MethodCounters* build_method_counters(Thread* current, Method* m);
350
351 int interpreter_invocation_count() { return invocation_count(); }
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 address verified_inline_code_entry();
364 address verified_inline_ro_code_entry();
365 bool check_code() const; // Not inline to avoid circular ref
366 CompiledMethod* code() const;
367
368 // Locks CompiledMethod_lock if not held.
369 void unlink_code(CompiledMethod *compare);
370 // Locks CompiledMethod_lock if not held.
371 void unlink_code();
372
373 private:
374 // Either called with CompiledMethod_lock held or from constructor.
375 void clear_code();
376
377 void clear_method_data() {
378 _method_data = nullptr;
379 }
380
381 public:
382 static void set_code(const methodHandle& mh, CompiledMethod* code);
383 void set_adapter_entry(AdapterHandlerEntry* adapter) {
384 _adapter = adapter;
385 }
386 void set_from_compiled_entry(address entry) {
387 _from_compiled_entry = entry;
388 }
389 void set_from_compiled_inline_ro_entry(address entry) {
390 _from_compiled_inline_ro_entry = entry;
391 }
392 void set_from_compiled_inline_entry(address entry) {
393 _from_compiled_inline_entry = entry;
394 }
395
396 address get_i2c_entry();
397 address get_c2i_entry();
398 address get_c2i_inline_entry();
399 address get_c2i_unverified_entry();
400 address get_c2i_unverified_inline_entry();
401 address get_c2i_no_clinit_check_entry();
402 AdapterHandlerEntry* adapter() const {
403 return _adapter;
404 }
405 // setup entry points
406 void link_method(const methodHandle& method, TRAPS);
407 // clear entry points. Used by sharing code during dump time
408 void unlink_method() NOT_CDS_RETURN;
409 void remove_unshareable_flags() NOT_CDS_RETURN;
410
411 // the number of argument reg slots that the compiled method uses on the stack.
412 int num_stack_arg_slots(bool rounded = true) const {
413 return rounded ? align_up(constMethod()->num_stack_arg_slots(), 2) : constMethod()->num_stack_arg_slots(); }
414
415 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
416 virtual MetaspaceObj::Type type() const { return MethodType; }
417
418 // vtable index
419 enum VtableIndexFlag {
420 // Valid vtable indexes are non-negative (>= 0).
421 // These few negative values are used as sentinels.
422 itable_index_max = -10, // first itable index, growing downward
423 pending_itable_index = -9, // itable index will be assigned
424 invalid_vtable_index = -4, // distinct from any valid vtable index
425 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
426 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
427 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
428 };
429 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
430 bool has_vtable_index() const { return _vtable_index >= 0; }
431 int vtable_index() const { return _vtable_index; }
432 void set_vtable_index(int index);
433 DEBUG_ONLY(bool valid_itable_index() const { return _vtable_index <= pending_itable_index; })
434 bool has_itable_index() const { return _vtable_index <= itable_index_max; }
435 int itable_index() const { assert(valid_itable_index(), "");
436 return itable_index_max - _vtable_index; }
437 void set_itable_index(int index);
438
439 // interpreter entry
440 address interpreter_entry() const { return _i2i_entry; }
441 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
442 void set_interpreter_entry(address entry) {
443 if (_i2i_entry != entry) {
444 _i2i_entry = entry;
445 }
446 if (_from_interpreted_entry != entry) {
447 _from_interpreted_entry = entry;
448 }
449 }
450
451 // native function (used for native methods only)
452 enum {
453 native_bind_event_is_interesting = true
454 };
455 address native_function() const { return *(native_function_addr()); }
456
457 // Must specify a real function (not null).
458 // Use clear_native_function() to unregister.
459 void set_native_function(address function, bool post_event_flag);
460 bool has_native_function() const;
461 void clear_native_function();
462
463 // signature handler (used for native methods only)
464 address signature_handler() const { return *(signature_handler_addr()); }
465 void set_signature_handler(address handler);
466
467 // Interpreter oopmap support
468 void mask_for(int bci, InterpreterOopMap* mask);
469
470 // operations on invocation counter
471 void print_invocation_count(outputStream* st);
472
473 // byte codes
474 void set_code(address code) { return constMethod()->set_code(code); }
475 address code_base() const { return constMethod()->code_base(); }
476 bool contains(address bcp) const { return constMethod()->contains(bcp); }
477
478 // prints byte codes
479 void print_codes(int flags = 0) const { print_codes_on(tty, flags); }
480 void print_codes_on(outputStream* st, int flags = 0) const;
481 void print_codes_on(int from, int to, outputStream* st, int flags = 0) const;
482
483 // method parameters
484 bool has_method_parameters() const
485 { return constMethod()->has_method_parameters(); }
486 int method_parameters_length() const
487 { return constMethod()->method_parameters_length(); }
488 MethodParametersElement* method_parameters_start() const
489 { return constMethod()->method_parameters_start(); }
490
491 // checked exceptions
492 u2 checked_exceptions_length() const
493 { return constMethod()->checked_exceptions_length(); }
494 CheckedExceptionElement* checked_exceptions_start() const
495 { return constMethod()->checked_exceptions_start(); }
496
497 // localvariable table
498 bool has_localvariable_table() const
499 { return constMethod()->has_localvariable_table(); }
500 u2 localvariable_table_length() const
501 { return constMethod()->localvariable_table_length(); }
502 LocalVariableTableElement* localvariable_table_start() const
503 { return constMethod()->localvariable_table_start(); }
504
505 bool has_linenumber_table() const
506 { return constMethod()->has_linenumber_table(); }
507 u_char* compressed_linenumber_table() const
508 { return constMethod()->compressed_linenumber_table(); }
509
510 // method holder (the Klass* holding this method)
511 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
512
513 Symbol* klass_name() const; // returns the name of the method holder
514 BasicType result_type() const { return constMethod()->result_type(); }
515 bool is_returning_oop() const { BasicType r = result_type(); return is_reference_type(r); }
516 InlineKlass* returns_inline_type(Thread* thread) const;
517
518 // Checked exceptions thrown by this method (resolved to mirrors)
519 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
520
521 // Access flags
522 bool is_public() const { return access_flags().is_public(); }
523 bool is_private() const { return access_flags().is_private(); }
524 bool is_protected() const { return access_flags().is_protected(); }
525 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
526 bool is_static() const { return access_flags().is_static(); }
527 bool is_final() const { return access_flags().is_final(); }
528 bool is_synchronized() const { return access_flags().is_synchronized();}
529 bool is_native() const { return access_flags().is_native(); }
530 bool is_abstract() const { return access_flags().is_abstract(); }
531 bool is_synthetic() const { return access_flags().is_synthetic(); }
532
533 // returns true if contains only return operation
534 bool is_empty_method() const;
535
536 // returns true if this is a vanilla constructor
537 bool is_vanilla_constructor() const;
538
539 // checks method and its method holder
540 bool is_final_method() const;
541 bool is_final_method(AccessFlags class_access_flags) const;
542 // interface method declared with 'default' - excludes private interface methods
543 bool is_default_method() const;
544
545 // true if method needs no dynamic dispatch (final and/or no vtable entry)
546 bool can_be_statically_bound() const;
547 bool can_be_statically_bound(InstanceKlass* context) const;
548 bool can_be_statically_bound(AccessFlags class_access_flags) const;
549
550 // true if method can omit stack trace in throw in compiled code.
551 bool can_omit_stack_trace();
552
553 // Flags getting and setting.
554 #define M_STATUS_GET_SET(name, ignore) \
555 bool name() const { return _flags.name(); } \
556 void set_##name(bool x) { _flags.set_##name(x); } \
557 void set_##name() { _flags.set_##name(true); }
558 M_STATUS_DO(M_STATUS_GET_SET)
559 #undef M_STATUS_GET_SET
560
561 // returns true if the method has any backward branches.
562 bool has_loops() {
563 return has_loops_flag_init() ? has_loops_flag() : compute_has_loops_flag();
564 };
565
566 bool compute_has_loops_flag();
567 bool set_has_loops() {
568 // set both the flags and that it's been initialized.
569 set_has_loops_flag();
570 set_has_loops_flag_init();
571 return true;
572 }
573
574 // returns true if the method has any monitors.
575 bool has_monitors() const { return is_synchronized() || has_monitor_bytecodes(); }
576
577 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
578 // properly nest in the method. It might return false, even though they actually nest properly, since the info.
579 // has not been computed yet.
580 bool guaranteed_monitor_matching() const { return monitor_matching(); }
581 void set_guaranteed_monitor_matching() { set_monitor_matching(); }
582
583 // returns true if the method is an accessor function (setter/getter).
584 bool is_accessor() const;
585
586 // returns true if the method is a getter
587 bool is_getter() const;
588
589 // returns true if the method is a setter
590 bool is_setter() const;
591
592 // returns true if the method does nothing but return a constant of primitive type
593 bool is_constant_getter() const;
594
595 // returns true if the method name is <clinit> and the method has
596 // valid static initializer flags.
597 bool is_class_initializer() const;
598
599 // returns true if the method name is <init>
600 bool is_object_constructor() const;
601
602 // compiled code support
603 // NOTE: code() is inherently racy as deopt can be clearing code
604 // simultaneously. Use with caution.
605 bool has_compiled_code() const;
606
607 bool needs_clinit_barrier() const;
608
609 // sizing
610 static int header_size() {
611 return align_up((int)sizeof(Method), wordSize) / wordSize;
612 }
613 static int size(bool is_native);
614 int size() const { return method_size(); }
615 void log_touched(Thread* current);
616 static void print_touched_methods(outputStream* out);
617
618 // interpreter support
619 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
620 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
621 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
622 static ByteSize from_compiled_inline_offset() { return byte_offset_of(Method, _from_compiled_inline_entry); }
623 static ByteSize from_compiled_inline_ro_offset(){ return byte_offset_of(Method, _from_compiled_inline_ro_entry); }
624 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
625 static ByteSize flags_offset() { return byte_offset_of(Method, _flags); }
626
627 static ByteSize method_counters_offset() {
628 return byte_offset_of(Method, _method_counters);
629 }
630 #ifndef PRODUCT
631 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
632 #endif // not PRODUCT
633 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
634 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
635 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
636 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
637 static ByteSize itable_index_offset() { return byte_offset_of(Method, _vtable_index ); }
638
639 // for code generation
640 static ByteSize method_data_offset() { return byte_offset_of(Method, _method_data); }
641 static ByteSize intrinsic_id_offset() { return byte_offset_of(Method, _intrinsic_id); }
642 static int intrinsic_id_size_in_bytes() { return sizeof(u2); }
643
644 // Static methods that are used to implement member methods where an exposed this pointer
645 // is needed due to possible GCs
646 static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
647
648 // Returns the byte code index from the byte code pointer
649 int bci_from(address bcp) const;
650 address bcp_from(int bci) const;
651 address bcp_from(address bcp) const;
652 int validate_bci_from_bcp(address bcp) const;
653 int validate_bci(int bci) const;
654
655 // Returns the line number for a bci if debugging information for the method is prowided,
656 // -1 is returned otherwise.
657 int line_number_from_bci(int bci) const;
658
659 // Reflection support
660 bool is_overridden_in(Klass* k) const;
661
662 // Stack walking support
663 bool is_ignored_by_security_stack_walk() const;
664
665 // JSR 292 support
666 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
667 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
668 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
669 static methodHandle make_method_handle_intrinsic(vmIntrinsicID iid, // _invokeBasic, _linkToVirtual
670 Symbol* signature, //anything at all
671 TRAPS);
672 // Some special methods don't need to be findable by nmethod iterators and are permanent.
673 bool can_be_allocated_in_NonNMethod_space() const { return is_method_handle_intrinsic(); }
674
675 // Continuation
676 inline bool is_continuation_enter_intrinsic() const;
677 inline bool is_continuation_yield_intrinsic() const;
678 inline bool is_continuation_native_intrinsic() const;
679 inline bool is_special_native_intrinsic() const;
680
681 static Klass* check_non_bcp_klass(Klass* klass);
682
683 enum {
684 // How many extra stack entries for invokedynamic
685 extra_stack_entries_for_jsr292 = 1
686 };
687
688 // this operates only on invoke methods:
689 // presize interpreter frames for extra interpreter stack entries, if needed
690 // Account for the extra appendix argument for invokehandle/invokedynamic
691 static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
692 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize
693
694 // RedefineClasses() support:
695 bool on_stack() const { return on_stack_flag(); }
696 void set_on_stack(const bool value);
697
698 void record_gc_epoch();
699
700 // see the definition in Method*.cpp for the gory details
701 bool should_not_be_cached() const;
702
703 // Rewriting support
704 static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
705 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
706
707 // jmethodID handling
708 // Because the useful life-span of a jmethodID cannot be determined,
709 // once created they are never reclaimed. The methods to which they refer,
710 // however, can be GC'ed away if the class is unloaded or if the method is
711 // made obsolete or deleted -- in these cases, the jmethodID
712 // refers to null (as is the case for any weak reference).
713 static jmethodID make_jmethod_id(ClassLoaderData* cld, Method* mh);
714 static void destroy_jmethod_id(ClassLoaderData* cld, jmethodID mid);
715
716 // Ensure there is enough capacity in the internal tracking data
717 // structures to hold the number of jmethodIDs you plan to generate.
718 // This saves substantial time doing allocations.
719 static void ensure_jmethod_ids(ClassLoaderData* cld, int capacity);
720
721 // Use resolve_jmethod_id() in situations where the caller is expected
722 // to provide a valid jmethodID; the only sanity checks are in asserts;
723 // result guaranteed not to be null.
724 inline static Method* resolve_jmethod_id(jmethodID mid) {
725 assert(mid != nullptr, "JNI method id should not be null");
726 return *((Method**)mid);
727 }
728
729 // Use checked_resolve_jmethod_id() in situations where the caller
730 // should provide a valid jmethodID, but might not. Null is returned
731 // when the jmethodID does not refer to a valid method.
732 static Method* checked_resolve_jmethod_id(jmethodID mid);
733
734 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
735 static bool is_method_id(jmethodID mid);
736
737 // Clear methods
738 static void clear_jmethod_ids(ClassLoaderData* loader_data);
739 void clear_jmethod_id();
740 static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
741
742 // Get this method's jmethodID -- allocate if it doesn't exist
743 jmethodID jmethod_id();
744
745 // Lookup the jmethodID for this method. Return null if not found.
746 // NOTE that this function can be called from a signal handler
747 // (see AsyncGetCallTrace support for Forte Analyzer) and this
748 // needs to be async-safe. No allocation should be done and
749 // so handles are not used to avoid deadlock.
750 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
751
752 // Support for inlining of intrinsic methods
753 vmIntrinsicID intrinsic_id() const { return (vmIntrinsicID) _intrinsic_id; }
754 void set_intrinsic_id(vmIntrinsicID id) { _intrinsic_id = (u2) id; }
755
756 // Helper routines for intrinsic_id() and vmIntrinsics::method().
757 void init_intrinsic_id(vmSymbolID klass_id); // updates from _none if a match
758 static vmSymbolID klass_id_for_intrinsics(const Klass* holder);
759
760 bool caller_sensitive() const { return constMethod()->caller_sensitive(); }
761 void set_caller_sensitive() { constMethod()->set_caller_sensitive(); }
762
763 bool changes_current_thread() const { return constMethod()->changes_current_thread(); }
764 void set_changes_current_thread() { constMethod()->set_changes_current_thread(); }
765
766 bool jvmti_mount_transition() const { return constMethod()->jvmti_mount_transition(); }
767 void set_jvmti_mount_transition() { constMethod()->set_jvmti_mount_transition(); }
768
769 bool is_hidden() const { return constMethod()->is_hidden(); }
770 void set_is_hidden() { constMethod()->set_is_hidden(); }
771
772 bool is_scoped() const { return constMethod()->is_scoped(); }
773 void set_scoped() { constMethod()->set_is_scoped(); }
774
775 bool intrinsic_candidate() const { return constMethod()->intrinsic_candidate(); }
776 void set_intrinsic_candidate() { constMethod()->set_intrinsic_candidate(); }
777
778 bool has_injected_profile() const { return constMethod()->has_injected_profile(); }
779 void set_has_injected_profile() { constMethod()->set_has_injected_profile(); }
780
781 bool has_reserved_stack_access() const { return constMethod()->reserved_stack_access(); }
782 void set_has_reserved_stack_access() { constMethod()->set_reserved_stack_access(); }
783
784 bool is_scalarized_arg(int idx) const;
785
786 bool c1_needs_stack_repair() const { return constMethod()->c1_needs_stack_repair(); }
787 void set_c1_needs_stack_repair() { constMethod()->set_c1_needs_stack_repair(); }
788
789 bool c2_needs_stack_repair() const { return constMethod()->c2_needs_stack_repair(); }
790 void set_c2_needs_stack_repair() { constMethod()->set_c2_needs_stack_repair(); }
791
792 bool mismatch() const { return constMethod()->mismatch(); }
793 void set_mismatch() { constMethod()->set_mismatch(); }
794
795 JFR_ONLY(DEFINE_TRACE_FLAG_ACCESSOR;)
796
797 ConstMethod::MethodType method_type() const {
798 return _constMethod->method_type();
799 }
800 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
801
802 // On-stack replacement support
803 bool has_osr_nmethod(int level, bool match_level) {
804 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != nullptr;
805 }
806
807 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
808 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
809 }
810
811 // Find if klass for method is loaded
812 bool is_klass_loaded_by_klass_index(int klass_index) const;
813 bool is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved = false) const;
814
815 // Indicates whether compilation failed earlier for this method, or
816 // whether it is not compilable for another reason like having a
817 // breakpoint set in it.
818 bool is_not_compilable(int comp_level = CompLevel_any) const;
819 void set_not_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
820 void set_not_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
821 set_not_compilable(reason, comp_level, false);
822 }
823 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
824 void set_not_osr_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
825 void set_not_osr_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
826 set_not_osr_compilable(reason, comp_level, false);
827 }
828 bool is_always_compilable() const;
829
830 private:
831 void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
832
833 public:
834 MethodCounters* get_method_counters(Thread* current) {
835 if (_method_counters == nullptr) {
836 build_method_counters(current, this);
837 }
838 return _method_counters;
839 }
840
841 void clear_is_not_c1_compilable() { set_is_not_c1_compilable(false); }
842 void clear_is_not_c2_compilable() { set_is_not_c2_compilable(false); }
843 void clear_is_not_c2_osr_compilable() { set_is_not_c2_osr_compilable(false); }
844
845 // not_c1_osr_compilable == not_c1_compilable
846 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); }
847 void set_is_not_c1_osr_compilable() { set_is_not_c1_compilable(); }
848 void clear_is_not_c1_osr_compilable() { clear_is_not_c1_compilable(); }
849
850 // Background compilation support
851 void clear_queued_for_compilation() { set_queued_for_compilation(false); }
852
853 // Resolve all classes in signature, return 'true' if successful
854 static bool load_signature_classes(const methodHandle& m, TRAPS);
855
856 // Printing
857 void print_short_name(outputStream* st = tty) const; // prints as klassname::methodname; Exposed so field engineers can debug VM
858 #if INCLUDE_JVMTI
859 void print_name(outputStream* st = tty) const; // prints as "virtual void foo(int)"; exposed for -Xlog:redefine+class
860 #else
861 void print_name(outputStream* st = tty) const PRODUCT_RETURN; // prints as "virtual void foo(int)"
862 #endif
863
864 typedef int (*method_comparator_func)(Method* a, Method* b);
865
866 // Helper routine used for method sorting
867 static void sort_methods(Array<Method*>* methods, bool set_idnums = true, method_comparator_func func = nullptr);
868
869 // Deallocation function for redefine classes or if an error occurs
870 void deallocate_contents(ClassLoaderData* loader_data);
871
872 void release_C_heap_structures();
873
874 Method* get_new_method() const {
875 InstanceKlass* holder = method_holder();
876 Method* new_method = holder->method_with_idnum(orig_method_idnum());
877
878 assert(new_method != nullptr, "method_with_idnum() should not be null");
879 assert(this != new_method, "sanity check");
880 return new_method;
881 }
882
883 // Printing
884 #ifndef PRODUCT
885 void print_on(outputStream* st) const;
886 #endif
887 void print_value_on(outputStream* st) const;
888 void print_linkage_flags(outputStream* st) PRODUCT_RETURN;
889
890 const char* internal_name() const { return "{method}"; }
891
892 // Check for valid method pointer
893 static bool has_method_vptr(const void* ptr);
894 static bool is_valid_method(const Method* m);
895
896 // Verify
897 void verify() { verify_on(tty); }
898 void verify_on(outputStream* st);
899
900 private:
901
902 // Inlined elements
903 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
904 address* signature_handler_addr() const { return native_function_addr() + 1; }
905 };
906
907
908 // Utility class for compressing line number tables
909
910 class CompressedLineNumberWriteStream: public CompressedWriteStream {
911 private:
912 int _bci;
913 int _line;
914 public:
915 // Constructor
916 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
917 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
918
919 // Write (bci, line number) pair to stream
920 void write_pair_regular(int bci_delta, int line_delta);
921
922 // If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
923 // we save it as one byte, otherwise we write a 0xFF escape character
924 // and use regular compression. 0x0 is used as end-of-stream terminator.
925 void write_pair_inline(int bci, int line);
926
927 void write_pair(int bci, int line);
928
929 // Write end-of-stream marker
930 void write_terminator() { write_byte(0); }
931 };
932
933
934 // Utility class for decompressing line number tables
935
936 class CompressedLineNumberReadStream: public CompressedReadStream {
937 private:
938 int _bci;
939 int _line;
940 public:
941 // Constructor
942 CompressedLineNumberReadStream(u_char* buffer);
943 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
944 bool read_pair();
945 // Accessing bci and line number (after calling read_pair)
946 int bci() const { return _bci; }
947 int line() const { return _line; }
948 };
949
950
951 #if INCLUDE_JVMTI
952
953 /// Fast Breakpoints.
954
955 // If this structure gets more complicated (because bpts get numerous),
956 // move it into its own header.
957
958 // There is presently no provision for concurrent access
959 // to breakpoint lists, which is only OK for JVMTI because
960 // breakpoints are written only at safepoints, and are read
961 // concurrently only outside of safepoints.
962
963 class BreakpointInfo : public CHeapObj<mtClass> {
964 friend class VMStructs;
965 private:
966 Bytecodes::Code _orig_bytecode;
967 int _bci;
968 u2 _name_index; // of method
969 u2 _signature_index; // of method
970 BreakpointInfo* _next; // simple storage allocation
971
972 public:
973 BreakpointInfo(Method* m, int bci);
974
975 // accessors
976 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
977 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
978 int bci() { return _bci; }
979
980 BreakpointInfo* next() const { return _next; }
981 void set_next(BreakpointInfo* n) { _next = n; }
982
983 // helps for searchers
984 bool match(const Method* m, int bci) {
985 return bci == _bci && match(m);
986 }
987
988 bool match(const Method* m) {
989 return _name_index == m->name_index() &&
990 _signature_index == m->signature_index();
991 }
992
993 void set(Method* method);
994 void clear(Method* method);
995 };
996
997 #endif // INCLUDE_JVMTI
998
999 // Utility class for access exception handlers
1000 class ExceptionTable : public StackObj {
1001 private:
1002 ExceptionTableElement* _table;
1003 u2 _length;
1004
1005 public:
1006 ExceptionTable(const Method* m) {
1007 if (m->has_exception_handler()) {
1008 _table = m->exception_table_start();
1009 _length = m->exception_table_length();
1010 } else {
1011 _table = nullptr;
1012 _length = 0;
1013 }
1014 }
1015
1016 u2 length() const {
1017 return _length;
1018 }
1019
1020 u2 start_pc(int idx) const {
1021 assert(idx < _length, "out of bounds");
1022 return _table[idx].start_pc;
1023 }
1024
1025 void set_start_pc(int idx, u2 value) {
1026 assert(idx < _length, "out of bounds");
1027 _table[idx].start_pc = value;
1028 }
1029
1030 u2 end_pc(int idx) const {
1031 assert(idx < _length, "out of bounds");
1032 return _table[idx].end_pc;
1033 }
1034
1035 void set_end_pc(int idx, u2 value) {
1036 assert(idx < _length, "out of bounds");
1037 _table[idx].end_pc = value;
1038 }
1039
1040 u2 handler_pc(int idx) const {
1041 assert(idx < _length, "out of bounds");
1042 return _table[idx].handler_pc;
1043 }
1044
1045 void set_handler_pc(int idx, u2 value) {
1046 assert(idx < _length, "out of bounds");
1047 _table[idx].handler_pc = value;
1048 }
1049
1050 u2 catch_type_index(int idx) const {
1051 assert(idx < _length, "out of bounds");
1052 return _table[idx].catch_type_index;
1053 }
1054
1055 void set_catch_type_index(int idx, u2 value) {
1056 assert(idx < _length, "out of bounds");
1057 _table[idx].catch_type_index = value;
1058 }
1059 };
1060
1061 #endif // SHARE_OOPS_METHOD_HPP