1 /*

     2  * Copyright (c) 1997, 2017, 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_VM_OOPS_METHODOOP_HPP

    26 #define SHARE_VM_OOPS_METHODOOP_HPP

    27 

    28 #include "classfile/vmSymbols.hpp"

    29 #include "code/compressedStream.hpp"

    30 #include "compiler/compilerDefinitions.hpp"

    31 #include "compiler/oopMap.hpp"

    32 #include "interpreter/invocationCounter.hpp"

    33 #include "oops/annotations.hpp"

    34 #include "oops/constantPool.hpp"

    35 #include "oops/methodCounters.hpp"

    36 #include "oops/instanceKlass.hpp"

    37 #include "oops/oop.hpp"

    38 #include "oops/typeArrayOop.hpp"

    39 #include "utilities/accessFlags.hpp"

    40 #include "utilities/align.hpp"

    41 #include "utilities/growableArray.hpp"

    42 

    43 // A Method represents a Java method.

    44 //

    45 // Note that most applications load thousands of methods, so keeping the size of this

    46 // class small has a big impact on footprint.

    47 //

    48 // Note that native_function and signature_handler have to be at fixed offsets

    49 // (required by the interpreter)

    50 //

    51 //  Method embedded field layout (after declared fields):

    52 //   [EMBEDDED native_function       (present only if native) ]

    53 //   [EMBEDDED signature_handler     (present only if native) ]

    54 

    55 class CheckedExceptionElement;

    56 class LocalVariableTableElement;

    57 class AdapterHandlerEntry;

    58 class MethodData;

    59 class MethodCounters;

    60 class ConstMethod;

    61 class InlineTableSizes;

    62 class KlassSizeStats;

    63 class CompiledMethod;

    64 

    65 class Method : public Metadata {

    66  friend class VMStructs;

    67  friend class JVMCIVMStructs;

    68  private:

    69   // If you add a new field that points to any metaspace object, you

    70   // must add this field to Method::metaspace_pointers_do().

    71   ConstMethod*      _constMethod;                // Method read-only data.

    72   MethodData*       _method_data;

    73   MethodCounters*   _method_counters;

    74   AccessFlags       _access_flags;               // Access flags

    75   int               _vtable_index;               // vtable index of this method (see VtableIndexFlag)

    76                                                  // note: can have vtables with >2**16 elements (because of inheritance)

    77   u2                _intrinsic_id;               // vmSymbols::intrinsic_id (0 == _none)

    78 

    79   // Flags

    80   enum Flags {

    81     _caller_sensitive      = 1 << 0,

    82     _force_inline          = 1 << 1,

    83     _dont_inline           = 1 << 2,

    84     _hidden                = 1 << 3,

    85     _has_injected_profile  = 1 << 4,

    86     _running_emcp          = 1 << 5,

    87     _intrinsic_candidate   = 1 << 6,

    88     _reserved_stack_access = 1 << 7

    89   };

    90   mutable u2 _flags;

    91 

    92   TRACE_DEFINE_FLAG;

    93 

    94 #ifndef PRODUCT

    95   int               _compiled_invocation_count;  // Number of nmethod invocations so far (for perf. debugging)

    96 #endif

    97   // Entry point for calling both from and to the interpreter.

    98   address _i2i_entry;           // All-args-on-stack calling convention

    99   // Entry point for calling from compiled code, to compiled code if it exists

   100   // or else the interpreter.

   101   volatile address _from_compiled_entry;        // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()

   102   // The entry point for calling both from and to compiled code is

   103   // "_code->entry_point()".  Because of tiered compilation and de-opt, this

   104   // field can come and go.  It can transition from NULL to not-null at any

   105   // time (whenever a compile completes).  It can transition from not-null to

   106   // NULL only at safepoints (because of a de-opt).

   107   CompiledMethod* volatile _code;                       // Points to the corresponding piece of native code

   108   volatile address           _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry

   109 

   110 #if INCLUDE_AOT && defined(TIERED)

   111   CompiledMethod* _aot_code;

   112 #endif

   113 

   114   // Constructor

   115   Method(ConstMethod* xconst, AccessFlags access_flags);

   116  public:

   117 

   118   static Method* allocate(ClassLoaderData* loader_data,

   119                           int byte_code_size,

   120                           AccessFlags access_flags,

   121                           InlineTableSizes* sizes,

   122                           ConstMethod::MethodType method_type,

   123                           TRAPS);

   124 

   125   // CDS and vtbl checking can create an empty Method to get vtbl pointer.

   126   Method(){}

   127 

   128   bool is_method() const volatile { return true; }

   129 

   130   void restore_unshareable_info(TRAPS);

   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   volatile address from_compiled_entry() const   { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }

   140   volatile address from_compiled_entry_no_trampoline() const;

   141   volatile address from_interpreted_entry() const{ return (address)OrderAccess::load_ptr_acquire(&_from_interpreted_entry); }

   142 

   143   // access flag

   144   AccessFlags access_flags() const               { return _access_flags;  }

   145   void set_access_flags(AccessFlags flags)       { _access_flags = flags; }

   146 

   147   // name

   148   Symbol* name() const                           { return constants()->symbol_at(name_index()); }

   149   int name_index() const                         { return constMethod()->name_index();         }

   150   void set_name_index(int index)                 { constMethod()->set_name_index(index);       }

   151 

   152   // signature

   153   Symbol* signature() const                      { return constants()->symbol_at(signature_index()); }

   154   int signature_index() const                    { return constMethod()->signature_index();         }

   155   void set_signature_index(int index)            { constMethod()->set_signature_index(index);       }

   156 

   157   // generics support

   158   Symbol* generic_signature() const              { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : (Symbol*)NULL); }

   159   int generic_signature_index() const            { return constMethod()->generic_signature_index(); }

   160   void set_generic_signature_index(int index)    { constMethod()->set_generic_signature_index(index); }

   161 

   162   // annotations support

   163   AnnotationArray* annotations() const           {

   164     return constMethod()->method_annotations();

   165   }

   166   AnnotationArray* parameter_annotations() const {

   167     return constMethod()->parameter_annotations();

   168   }

   169   AnnotationArray* annotation_default() const    {

   170     return constMethod()->default_annotations();

   171   }

   172   AnnotationArray* type_annotations() const      {

   173     return constMethod()->type_annotations();

   174   }

   175 

   176   // Helper routine: get klass name + "." + method name + signature as

   177   // C string, for the purpose of providing more useful NoSuchMethodErrors

   178   // and fatal error handling. The string is allocated in resource

   179   // area if a buffer is not provided by the caller.

   180   char* name_and_sig_as_C_string() const;

   181   char* name_and_sig_as_C_string(char* buf, int size) const;

   182 

   183   // Static routine in the situations we don't have a Method*

   184   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);

   185   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);

   186 

   187   Bytecodes::Code java_code_at(int bci) const {

   188     return Bytecodes::java_code_at(this, bcp_from(bci));

   189   }

   190   Bytecodes::Code code_at(int bci) const {

   191     return Bytecodes::code_at(this, bcp_from(bci));

   192   }

   193 

   194   // JVMTI breakpoints

   195 #if !INCLUDE_JVMTI

   196   Bytecodes::Code orig_bytecode_at(int bci) const {

   197     ShouldNotReachHere();

   198     return Bytecodes::_shouldnotreachhere;

   199   }

   200   void set_orig_bytecode_at(int bci, Bytecodes::Code code) {

   201     ShouldNotReachHere();

   202   };

   203   u2   number_of_breakpoints() const {return 0;}

   204 #else // !INCLUDE_JVMTI

   205   Bytecodes::Code orig_bytecode_at(int bci) const;

   206   void set_orig_bytecode_at(int bci, Bytecodes::Code code);

   207   void set_breakpoint(int bci);

   208   void clear_breakpoint(int bci);

   209   void clear_all_breakpoints();

   210   // Tracking number of breakpoints, for fullspeed debugging.

   211   // Only mutated by VM thread.

   212   u2   number_of_breakpoints()             const {

   213     MethodCounters* mcs = method_counters();

   214     if (mcs == NULL) {

   215       return 0;

   216     } else {

   217       return mcs->number_of_breakpoints();

   218     }

   219   }

   220   void incr_number_of_breakpoints(TRAPS)         {

   221     MethodCounters* mcs = get_method_counters(CHECK);

   222     if (mcs != NULL) {

   223       mcs->incr_number_of_breakpoints();

   224     }

   225   }

   226   void decr_number_of_breakpoints(TRAPS)         {

   227     MethodCounters* mcs = get_method_counters(CHECK);

   228     if (mcs != NULL) {

   229       mcs->decr_number_of_breakpoints();

   230     }

   231   }

   232   // Initialization only

   233   void clear_number_of_breakpoints()             {

   234     MethodCounters* mcs = method_counters();

   235     if (mcs != NULL) {

   236       mcs->clear_number_of_breakpoints();

   237     }

   238   }

   239 #endif // !INCLUDE_JVMTI

   240 

   241   // index into InstanceKlass methods() array

   242   // note: also used by jfr

   243   u2 method_idnum() const           { return constMethod()->method_idnum(); }

   244   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }

   245 

   246   u2 orig_method_idnum() const           { return constMethod()->orig_method_idnum(); }

   247   void set_orig_method_idnum(u2 idnum)   { constMethod()->set_orig_method_idnum(idnum); }

   248 

   249   // code size

   250   int code_size() const                  { return constMethod()->code_size(); }

   251 

   252   // method size in words

   253   int method_size() const                { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }

   254 

   255   // constant pool for Klass* holding this method

   256   ConstantPool* constants() const              { return constMethod()->constants(); }

   257   void set_constants(ConstantPool* c)          { constMethod()->set_constants(c); }

   258 

   259   // max stack

   260   // return original max stack size for method verification

   261   int  verifier_max_stack() const                { return constMethod()->max_stack(); }

   262   int           max_stack() const                { return constMethod()->max_stack() + extra_stack_entries(); }

   263   void      set_max_stack(int size)              {        constMethod()->set_max_stack(size); }

   264 

   265   // max locals

   266   int  max_locals() const                        { return constMethod()->max_locals(); }

   267   void set_max_locals(int size)                  { constMethod()->set_max_locals(size); }

   268 

   269   int highest_comp_level() const;

   270   void set_highest_comp_level(int level);

   271   int highest_osr_comp_level() const;

   272   void set_highest_osr_comp_level(int level);

   273 

   274 #if defined(COMPILER2) || INCLUDE_JVMCI

   275   // Count of times method was exited via exception while interpreting

   276   void interpreter_throwout_increment(TRAPS) {

   277     MethodCounters* mcs = get_method_counters(CHECK);

   278     if (mcs != NULL) {

   279       mcs->interpreter_throwout_increment();

   280     }

   281   }

   282 #endif

   283 

   284   int  interpreter_throwout_count() const        {

   285     MethodCounters* mcs = method_counters();

   286     if (mcs == NULL) {

   287       return 0;

   288     } else {

   289       return mcs->interpreter_throwout_count();

   290     }

   291   }

   292 

   293   // size of parameters

   294   int  size_of_parameters() const                { return constMethod()->size_of_parameters(); }

   295   void set_size_of_parameters(int size)          { constMethod()->set_size_of_parameters(size); }

   296 

   297   bool has_stackmap_table() const {

   298     return constMethod()->has_stackmap_table();

   299   }

   300 

   301   Array<u1>* stackmap_data() const {

   302     return constMethod()->stackmap_data();

   303   }

   304 

   305   void set_stackmap_data(Array<u1>* sd) {

   306     constMethod()->set_stackmap_data(sd);

   307   }

   308 

   309   // exception handler table

   310   bool has_exception_handler() const

   311                              { return constMethod()->has_exception_handler(); }

   312   int exception_table_length() const

   313                              { return constMethod()->exception_table_length(); }

   314   ExceptionTableElement* exception_table_start() const

   315                              { return constMethod()->exception_table_start(); }

   316 

   317   // Finds the first entry point bci of an exception handler for an

   318   // exception of klass ex_klass thrown at throw_bci. A value of NULL

   319   // for ex_klass indicates that the exception klass is not known; in

   320   // this case it matches any constraint class. Returns -1 if the

   321   // exception cannot be handled in this method. The handler

   322   // constraint classes are loaded if necessary. Note that this may

   323   // throw an exception if loading of the constraint classes causes

   324   // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.

   325   // If an exception is thrown, returns the bci of the

   326   // exception handler which caused the exception to be thrown, which

   327   // is needed for proper retries. See, for example,

   328   // InterpreterRuntime::exception_handler_for_exception.

   329   static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);

   330 

   331   // method data access

   332   MethodData* method_data() const              {

   333     return _method_data;

   334   }

   335 

   336   void set_method_data(MethodData* data)       {

   337     // The store into method must be released. On platforms without

   338     // total store order (TSO) the reference may become visible before

   339     // the initialization of data otherwise.

   340     OrderAccess::release_store_ptr((volatile void *)&_method_data, data);

   341   }

   342 

   343   MethodCounters* method_counters() const {

   344     return _method_counters;

   345   }

   346 

   347   void clear_method_counters() {

   348     _method_counters = NULL;

   349   }

   350 

   351   bool init_method_counters(MethodCounters* counters) {

   352     // Try to install a pointer to MethodCounters, return true on success.

   353     return Atomic::cmpxchg_ptr(counters, (volatile void*)&_method_counters, NULL) == NULL;

   354   }

   355 

   356 #ifdef TIERED

   357   // We are reusing interpreter_invocation_count as a holder for the previous event count!

   358   // We can do that since interpreter_invocation_count is not used in tiered.

   359   int prev_event_count() const                   {

   360     if (method_counters() == NULL) {

   361       return 0;

   362     } else {

   363       return method_counters()->interpreter_invocation_count();

   364     }

   365   }

   366   void set_prev_event_count(int count) {

   367     MethodCounters* mcs = method_counters();

   368     if (mcs != NULL) {

   369       mcs->set_interpreter_invocation_count(count);

   370     }

   371   }

   372   jlong prev_time() const                        {

   373     MethodCounters* mcs = method_counters();

   374     return mcs == NULL ? 0 : mcs->prev_time();

   375   }

   376   void set_prev_time(jlong time) {

   377     MethodCounters* mcs = method_counters();

   378     if (mcs != NULL) {

   379       mcs->set_prev_time(time);

   380     }

   381   }

   382   float rate() const                             {

   383     MethodCounters* mcs = method_counters();

   384     return mcs == NULL ? 0 : mcs->rate();

   385   }

   386   void set_rate(float rate) {

   387     MethodCounters* mcs = method_counters();

   388     if (mcs != NULL) {

   389       mcs->set_rate(rate);

   390     }

   391   }

   392 

   393 #if INCLUDE_AOT

   394   void set_aot_code(CompiledMethod* aot_code) {

   395     _aot_code = aot_code;

   396   }

   397 

   398   CompiledMethod* aot_code() const {

   399     return _aot_code;

   400   }

   401 #else

   402   CompiledMethod* aot_code() const { return NULL; }

   403 #endif // INCLUDE_AOT

   404 #endif // TIERED

   405 

   406   int nmethod_age() const {

   407     if (method_counters() == NULL) {

   408       return INT_MAX;

   409     } else {

   410       return method_counters()->nmethod_age();

   411     }

   412   }

   413 

   414   int invocation_count();

   415   int backedge_count();

   416 

   417   bool was_executed_more_than(int n);

   418   bool was_never_executed()                      { return !was_executed_more_than(0); }

   419 

   420   static void build_interpreter_method_data(const methodHandle& method, TRAPS);

   421 

   422   static MethodCounters* build_method_counters(Method* m, TRAPS);

   423 

   424   int interpreter_invocation_count() {

   425     if (TieredCompilation) {

   426       return invocation_count();

   427     } else {

   428       MethodCounters* mcs = method_counters();

   429       return (mcs == NULL) ? 0 : mcs->interpreter_invocation_count();

   430     }

   431   }

   432 #if defined(COMPILER2) || INCLUDE_JVMCI

   433   int increment_interpreter_invocation_count(TRAPS) {

   434     if (TieredCompilation) ShouldNotReachHere();

   435     MethodCounters* mcs = get_method_counters(CHECK_0);

   436     return (mcs == NULL) ? 0 : mcs->increment_interpreter_invocation_count();

   437   }

   438 #endif

   439 

   440 #ifndef PRODUCT

   441   int  compiled_invocation_count() const         { return _compiled_invocation_count;  }

   442   void set_compiled_invocation_count(int count)  { _compiled_invocation_count = count; }

   443 #else

   444   // for PrintMethodData in a product build

   445   int  compiled_invocation_count() const         { return 0;  }

   446 #endif // not PRODUCT

   447 

   448   // Clear (non-shared space) pointers which could not be relevant

   449   // if this (shared) method were mapped into another JVM.

   450   void remove_unshareable_info();

   451 

   452   // nmethod/verified compiler entry

   453   address verified_code_entry();

   454   bool check_code() const;      // Not inline to avoid circular ref

   455   CompiledMethod* volatile code() const                 { assert( check_code(), "" ); return (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code); }

   456   void clear_code(bool acquire_lock = true);    // Clear out any compiled code

   457   static void set_code(const methodHandle& mh, CompiledMethod* code);

   458   void set_adapter_entry(AdapterHandlerEntry* adapter) {

   459     constMethod()->set_adapter_entry(adapter);

   460   }

   461   void update_adapter_trampoline(AdapterHandlerEntry* adapter) {

   462     constMethod()->update_adapter_trampoline(adapter);

   463   }

   464 

   465   address get_i2c_entry();

   466   address get_c2i_entry();

   467   address get_c2i_unverified_entry();

   468   AdapterHandlerEntry* adapter() const {

   469     return constMethod()->adapter();

   470   }

   471   // setup entry points

   472   void link_method(const methodHandle& method, TRAPS);

   473   // clear entry points. Used by sharing code during dump time

   474   void unlink_method() NOT_CDS_RETURN;

   475 

   476   virtual void metaspace_pointers_do(MetaspaceClosure* iter);

   477   virtual MetaspaceObj::Type type() const { return MethodType; }

   478 

   479   // vtable index

   480   enum VtableIndexFlag {

   481     // Valid vtable indexes are non-negative (>= 0).

   482     // These few negative values are used as sentinels.

   483     itable_index_max        = -10, // first itable index, growing downward

   484     pending_itable_index    = -9,  // itable index will be assigned

   485     invalid_vtable_index    = -4,  // distinct from any valid vtable index

   486     garbage_vtable_index    = -3,  // not yet linked; no vtable layout yet

   487     nonvirtual_vtable_index = -2   // there is no need for vtable dispatch

   488     // 6330203 Note:  Do not use -1, which was overloaded with many meanings.

   489   };

   490   DEBUG_ONLY(bool valid_vtable_index() const     { return _vtable_index >= nonvirtual_vtable_index; })

   491   bool has_vtable_index() const                  { return _vtable_index >= 0; }

   492   int  vtable_index() const                      { return _vtable_index; }

   493   void set_vtable_index(int index);

   494   DEBUG_ONLY(bool valid_itable_index() const     { return _vtable_index <= pending_itable_index; })

   495   bool has_itable_index() const                  { return _vtable_index <= itable_index_max; }

   496   int  itable_index() const                      { assert(valid_itable_index(), "");

   497                                                    return itable_index_max - _vtable_index; }

   498   void set_itable_index(int index);

   499 

   500   // interpreter entry

   501   address interpreter_entry() const              { return _i2i_entry; }

   502   // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry

   503   void set_interpreter_entry(address entry) {

   504     assert(!is_shared(), "shared method's interpreter entry should not be changed at run time");

   505     if (_i2i_entry != entry) {

   506       _i2i_entry = entry;

   507     }

   508     if (_from_interpreted_entry != entry) {

   509       _from_interpreted_entry = entry;

   510     }

   511   }

   512 

   513   // native function (used for native methods only)

   514   enum {

   515     native_bind_event_is_interesting = true

   516   };

   517   address native_function() const                { return *(native_function_addr()); }

   518   address critical_native_function();

   519 

   520   // Must specify a real function (not NULL).

   521   // Use clear_native_function() to unregister.

   522   void set_native_function(address function, bool post_event_flag);

   523   bool has_native_function() const;

   524   void clear_native_function();

   525 

   526   // signature handler (used for native methods only)

   527   address signature_handler() const              { return *(signature_handler_addr()); }

   528   void set_signature_handler(address handler);

   529 

   530   // Interpreter oopmap support

   531   void mask_for(int bci, InterpreterOopMap* mask);

   532 

   533   // operations on invocation counter

   534   void print_invocation_count();

   535 

   536   // byte codes

   537   void    set_code(address code)      { return constMethod()->set_code(code); }

   538   address code_base() const           { return constMethod()->code_base(); }

   539   bool    contains(address bcp) const { return constMethod()->contains(bcp); }

   540 

   541   // prints byte codes

   542   void print_codes() const            { print_codes_on(tty); }

   543   void print_codes_on(outputStream* st) const;

   544   void print_codes_on(int from, int to, outputStream* st) const;

   545 

   546   // method parameters

   547   bool has_method_parameters() const

   548                          { return constMethod()->has_method_parameters(); }

   549   int method_parameters_length() const

   550                          { return constMethod()->method_parameters_length(); }

   551   MethodParametersElement* method_parameters_start() const

   552                           { return constMethod()->method_parameters_start(); }

   553 

   554   // checked exceptions

   555   int checked_exceptions_length() const

   556                          { return constMethod()->checked_exceptions_length(); }

   557   CheckedExceptionElement* checked_exceptions_start() const

   558                           { return constMethod()->checked_exceptions_start(); }

   559 

   560   // localvariable table

   561   bool has_localvariable_table() const

   562                           { return constMethod()->has_localvariable_table(); }

   563   int localvariable_table_length() const

   564                         { return constMethod()->localvariable_table_length(); }

   565   LocalVariableTableElement* localvariable_table_start() const

   566                          { return constMethod()->localvariable_table_start(); }

   567 

   568   bool has_linenumber_table() const

   569                               { return constMethod()->has_linenumber_table(); }

   570   u_char* compressed_linenumber_table() const

   571                        { return constMethod()->compressed_linenumber_table(); }

   572 

   573   // method holder (the Klass* holding this method)

   574   InstanceKlass* method_holder() const         { return constants()->pool_holder(); }

   575 

   576   void compute_size_of_parameters(Thread *thread); // word size of parameters (receiver if any + arguments)

   577   Symbol* klass_name() const;                    // returns the name of the method holder

   578   BasicType result_type() const;                 // type of the method result

   579   bool is_returning_oop() const                  { BasicType r = result_type(); return (r == T_OBJECT || r == T_ARRAY); }

   580   bool is_returning_fp() const                   { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }

   581 

   582   // Checked exceptions thrown by this method (resolved to mirrors)

   583   objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }

   584 

   585   // Access flags

   586   bool is_public() const                         { return access_flags().is_public();      }

   587   bool is_private() const                        { return access_flags().is_private();     }

   588   bool is_protected() const                      { return access_flags().is_protected();   }

   589   bool is_package_private() const                { return !is_public() && !is_private() && !is_protected(); }

   590   bool is_static() const                         { return access_flags().is_static();      }

   591   bool is_final() const                          { return access_flags().is_final();       }

   592   bool is_synchronized() const                   { return access_flags().is_synchronized();}

   593   bool is_native() const                         { return access_flags().is_native();      }

   594   bool is_abstract() const                       { return access_flags().is_abstract();    }

   595   bool is_strict() const                         { return access_flags().is_strict();      }

   596   bool is_synthetic() const                      { return access_flags().is_synthetic();   }

   597 

   598   // returns true if contains only return operation

   599   bool is_empty_method() const;

   600 

   601   // returns true if this is a vanilla constructor

   602   bool is_vanilla_constructor() const;

   603 

   604   // checks method and its method holder

   605   bool is_final_method() const;

   606   bool is_final_method(AccessFlags class_access_flags) const;

   607   // interface method declared with 'default' - excludes private interface methods

   608   bool is_default_method() const;

   609 

   610   // true if method needs no dynamic dispatch (final and/or no vtable entry)

   611   bool can_be_statically_bound() const;

   612   bool can_be_statically_bound(AccessFlags class_access_flags) const;

   613 

   614   // returns true if the method has any backward branches.

   615   bool has_loops() {

   616     return access_flags().loops_flag_init() ? access_flags().has_loops() : compute_has_loops_flag();

   617   };

   618 

   619   bool compute_has_loops_flag();

   620 

   621   bool has_jsrs() {

   622     return access_flags().has_jsrs();

   623   };

   624   void set_has_jsrs() {

   625     _access_flags.set_has_jsrs();

   626   }

   627 

   628   // returns true if the method has any monitors.

   629   bool has_monitors() const                      { return is_synchronized() || access_flags().has_monitor_bytecodes(); }

   630   bool has_monitor_bytecodes() const             { return access_flags().has_monitor_bytecodes(); }

   631 

   632   void set_has_monitor_bytecodes()               { _access_flags.set_has_monitor_bytecodes(); }

   633 

   634   // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes

   635   // propererly nest in the method. It might return false, even though they actually nest properly, since the info.

   636   // has not been computed yet.

   637   bool guaranteed_monitor_matching() const       { return access_flags().is_monitor_matching(); }

   638   void set_guaranteed_monitor_matching()         { _access_flags.set_monitor_matching(); }

   639 

   640   // returns true if the method is an accessor function (setter/getter).

   641   bool is_accessor() const;

   642 

   643   // returns true if the method is a getter

   644   bool is_getter() const;

   645 

   646   // returns true if the method is a setter

   647   bool is_setter() const;

   648 

   649   // returns true if the method does nothing but return a constant of primitive type

   650   bool is_constant_getter() const;

   651 

   652   // returns true if the method is an initializer (<init> or <clinit>).

   653   bool is_initializer() const;

   654 

   655   // returns true if the method is static OR if the classfile version < 51

   656   bool has_valid_initializer_flags() const;

   657 

   658   // returns true if the method name is <clinit> and the method has

   659   // valid static initializer flags.

   660   bool is_static_initializer() const;

   661 

   662   // returns true if the method name is <init>

   663   bool is_object_initializer() const;

   664 

   665   // compiled code support

   666   // NOTE: code() is inherently racy as deopt can be clearing code

   667   // simultaneously. Use with caution.

   668   bool has_compiled_code() const                 { return code() != NULL; }

   669 

   670 #ifdef TIERED

   671   bool has_aot_code() const                      { return aot_code() != NULL; }

   672 #endif

   673 

   674   // sizing

   675   static int header_size()                       {

   676     return align_up((int)sizeof(Method), wordSize) / wordSize;

   677   }

   678   static int size(bool is_native);

   679   int size() const                               { return method_size(); }

   680 #if INCLUDE_SERVICES

   681   void collect_statistics(KlassSizeStats *sz) const;

   682 #endif

   683   void log_touched(TRAPS);

   684   static void print_touched_methods(outputStream* out);

   685 

   686   // interpreter support

   687   static ByteSize const_offset()                 { return byte_offset_of(Method, _constMethod       ); }

   688   static ByteSize access_flags_offset()          { return byte_offset_of(Method, _access_flags      ); }

   689   static ByteSize from_compiled_offset()         { return byte_offset_of(Method, _from_compiled_entry); }

   690   static ByteSize code_offset()                  { return byte_offset_of(Method, _code); }

   691   static ByteSize method_data_offset()           {

   692     return byte_offset_of(Method, _method_data);

   693   }

   694   static ByteSize method_counters_offset()       {

   695     return byte_offset_of(Method, _method_counters);

   696   }

   697 #ifndef PRODUCT

   698   static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }

   699 #endif // not PRODUCT

   700   static ByteSize native_function_offset()       { return in_ByteSize(sizeof(Method));                 }

   701   static ByteSize from_interpreted_offset()      { return byte_offset_of(Method, _from_interpreted_entry ); }

   702   static ByteSize interpreter_entry_offset()     { return byte_offset_of(Method, _i2i_entry ); }

   703   static ByteSize signature_handler_offset()     { return in_ByteSize(sizeof(Method) + wordSize);      }

   704 

   705   // for code generation

   706   static int method_data_offset_in_bytes()       { return offset_of(Method, _method_data); }

   707   static int intrinsic_id_offset_in_bytes()      { return offset_of(Method, _intrinsic_id); }

   708   static int intrinsic_id_size_in_bytes()        { return sizeof(u2); }

   709 

   710   // Static methods that are used to implement member methods where an exposed this pointer

   711   // is needed due to possible GCs

   712   static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);

   713 

   714   // Returns the byte code index from the byte code pointer

   715   int     bci_from(address bcp) const;

   716   address bcp_from(int bci) const;

   717   address bcp_from(address bcp) const;

   718   int validate_bci_from_bcp(address bcp) const;

   719   int validate_bci(int bci) const;

   720 

   721   // Returns the line number for a bci if debugging information for the method is prowided,

   722   // -1 is returned otherwise.

   723   int line_number_from_bci(int bci) const;

   724 

   725   // Reflection support

   726   bool is_overridden_in(Klass* k) const;

   727 

   728   // Stack walking support

   729   bool is_ignored_by_security_stack_walk() const;

   730 

   731   // JSR 292 support

   732   bool is_method_handle_intrinsic() const;          // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)

   733   bool is_compiled_lambda_form() const;             // intrinsic_id() == vmIntrinsics::_compiledLambdaForm

   734   bool has_member_arg() const;                      // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.

   735   static methodHandle make_method_handle_intrinsic(vmIntrinsics::ID iid, // _invokeBasic, _linkToVirtual

   736                                                    Symbol* signature, //anything at all

   737                                                    TRAPS);

   738   static Klass* check_non_bcp_klass(Klass* klass);

   739 

   740   enum {

   741     // How many extra stack entries for invokedynamic

   742     extra_stack_entries_for_jsr292 = 1

   743   };

   744 

   745   // this operates only on invoke methods:

   746   // presize interpreter frames for extra interpreter stack entries, if needed

   747   // Account for the extra appendix argument for invokehandle/invokedynamic

   748   static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }

   749   static int extra_stack_words();  // = extra_stack_entries() * Interpreter::stackElementSize

   750 

   751   // RedefineClasses() support:

   752   bool is_old() const                               { return access_flags().is_old(); }

   753   void set_is_old()                                 { _access_flags.set_is_old(); }

   754   bool is_obsolete() const                          { return access_flags().is_obsolete(); }

   755   void set_is_obsolete()                            { _access_flags.set_is_obsolete(); }

   756   bool is_deleted() const                           { return access_flags().is_deleted(); }

   757   void set_is_deleted()                             { _access_flags.set_is_deleted(); }

   758 

   759   bool is_running_emcp() const {

   760     // EMCP methods are old but not obsolete or deleted. Equivalent

   761     // Modulo Constant Pool means the method is equivalent except

   762     // the constant pool and instructions that access the constant

   763     // pool might be different.

   764     // If a breakpoint is set in a redefined method, its EMCP methods that are

   765     // still running must have a breakpoint also.

   766     return (_flags & _running_emcp) != 0;

   767   }

   768 

   769   void set_running_emcp(bool x) {

   770     _flags = x ? (_flags | _running_emcp) : (_flags & ~_running_emcp);

   771   }

   772 

   773   bool on_stack() const                             { return access_flags().on_stack(); }

   774   void set_on_stack(const bool value);

   775 

   776   // see the definition in Method*.cpp for the gory details

   777   bool should_not_be_cached() const;

   778 

   779   // JVMTI Native method prefixing support:

   780   bool is_prefixed_native() const                   { return access_flags().is_prefixed_native(); }

   781   void set_is_prefixed_native()                     { _access_flags.set_is_prefixed_native(); }

   782 

   783   // Rewriting support

   784   static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,

   785                                           u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);

   786 

   787   // jmethodID handling

   788   // Because the useful life-span of a jmethodID cannot be determined,

   789   // once created they are never reclaimed.  The methods to which they refer,

   790   // however, can be GC'ed away if the class is unloaded or if the method is

   791   // made obsolete or deleted -- in these cases, the jmethodID

   792   // refers to NULL (as is the case for any weak reference).

   793   static jmethodID make_jmethod_id(ClassLoaderData* loader_data, Method* mh);

   794   static void destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID mid);

   795 

   796   // Ensure there is enough capacity in the internal tracking data

   797   // structures to hold the number of jmethodIDs you plan to generate.

   798   // This saves substantial time doing allocations.

   799   static void ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity);

   800 

   801   // Use resolve_jmethod_id() in situations where the caller is expected

   802   // to provide a valid jmethodID; the only sanity checks are in asserts;

   803   // result guaranteed not to be NULL.

   804   inline static Method* resolve_jmethod_id(jmethodID mid) {

   805     assert(mid != NULL, "JNI method id should not be null");

   806     return *((Method**)mid);

   807   }

   808 

   809   // Use checked_resolve_jmethod_id() in situations where the caller

   810   // should provide a valid jmethodID, but might not. NULL is returned

   811   // when the jmethodID does not refer to a valid method.

   812   static Method* checked_resolve_jmethod_id(jmethodID mid);

   813 

   814   static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);

   815   static bool is_method_id(jmethodID mid);

   816 

   817   // Clear methods

   818   static void clear_jmethod_ids(ClassLoaderData* loader_data);

   819   static void print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;

   820 

   821   // Get this method's jmethodID -- allocate if it doesn't exist

   822   jmethodID jmethod_id()                            { return method_holder()->get_jmethod_id(this); }

   823 

   824   // Lookup the jmethodID for this method.  Return NULL if not found.

   825   // NOTE that this function can be called from a signal handler

   826   // (see AsyncGetCallTrace support for Forte Analyzer) and this

   827   // needs to be async-safe. No allocation should be done and

   828   // so handles are not used to avoid deadlock.

   829   jmethodID find_jmethod_id_or_null()               { return method_holder()->jmethod_id_or_null(this); }

   830 

   831   // Support for inlining of intrinsic methods

   832   vmIntrinsics::ID intrinsic_id() const          { return (vmIntrinsics::ID) _intrinsic_id;           }

   833   void     set_intrinsic_id(vmIntrinsics::ID id) {                           _intrinsic_id = (u2) id; }

   834 

   835   // Helper routines for intrinsic_id() and vmIntrinsics::method().

   836   void init_intrinsic_id();     // updates from _none if a match

   837   static vmSymbols::SID klass_id_for_intrinsics(const Klass* holder);

   838 

   839   bool caller_sensitive() {

   840     return (_flags & _caller_sensitive) != 0;

   841   }

   842   void set_caller_sensitive(bool x) {

   843     _flags = x ? (_flags | _caller_sensitive) : (_flags & ~_caller_sensitive);

   844   }

   845 

   846   bool force_inline() {

   847     return (_flags & _force_inline) != 0;

   848   }

   849   void set_force_inline(bool x) {

   850     _flags = x ? (_flags | _force_inline) : (_flags & ~_force_inline);

   851   }

   852 

   853   bool dont_inline() {

   854     return (_flags & _dont_inline) != 0;

   855   }

   856   void set_dont_inline(bool x) {

   857     _flags = x ? (_flags | _dont_inline) : (_flags & ~_dont_inline);

   858   }

   859 

   860   bool is_hidden() {

   861     return (_flags & _hidden) != 0;

   862   }

   863   void set_hidden(bool x) {

   864     _flags = x ? (_flags | _hidden) : (_flags & ~_hidden);

   865   }

   866 

   867   bool intrinsic_candidate() {

   868     return (_flags & _intrinsic_candidate) != 0;

   869   }

   870   void set_intrinsic_candidate(bool x) {

   871     _flags = x ? (_flags | _intrinsic_candidate) : (_flags & ~_intrinsic_candidate);

   872   }

   873 

   874   bool has_injected_profile() {

   875     return (_flags & _has_injected_profile) != 0;

   876   }

   877   void set_has_injected_profile(bool x) {

   878     _flags = x ? (_flags | _has_injected_profile) : (_flags & ~_has_injected_profile);

   879   }

   880 

   881   bool has_reserved_stack_access() {

   882     return (_flags & _reserved_stack_access) != 0;

   883   }

   884 

   885   void set_has_reserved_stack_access(bool x) {

   886     _flags = x ? (_flags | _reserved_stack_access) : (_flags & ~_reserved_stack_access);

   887   }

   888 

   889   TRACE_DEFINE_FLAG_ACCESSOR;

   890 

   891   ConstMethod::MethodType method_type() const {

   892       return _constMethod->method_type();

   893   }

   894   bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }

   895 

   896   // On-stack replacement support

   897   bool has_osr_nmethod(int level, bool match_level) {

   898    return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != NULL;

   899   }

   900 

   901   int mark_osr_nmethods() {

   902     return method_holder()->mark_osr_nmethods(this);

   903   }

   904 

   905   nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {

   906     return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);

   907   }

   908 

   909   // Inline cache support

   910   void cleanup_inline_caches();

   911 

   912   // Find if klass for method is loaded

   913   bool is_klass_loaded_by_klass_index(int klass_index) const;

   914   bool is_klass_loaded(int refinfo_index, bool must_be_resolved = false) const;

   915 

   916   // Indicates whether compilation failed earlier for this method, or

   917   // whether it is not compilable for another reason like having a

   918   // breakpoint set in it.

   919   bool  is_not_compilable(int comp_level = CompLevel_any) const;

   920   void set_not_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);

   921   void set_not_compilable_quietly(int comp_level = CompLevel_all) {

   922     set_not_compilable(comp_level, false);

   923   }

   924   bool  is_not_osr_compilable(int comp_level = CompLevel_any) const;

   925   void set_not_osr_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);

   926   void set_not_osr_compilable_quietly(int comp_level = CompLevel_all) {

   927     set_not_osr_compilable(comp_level, false);

   928   }

   929   bool is_always_compilable() const;

   930 

   931  private:

   932   void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);

   933 

   934  public:

   935   MethodCounters* get_method_counters(TRAPS) {

   936     if (_method_counters == NULL) {

   937       build_method_counters(this, CHECK_AND_CLEAR_NULL);

   938     }

   939     return _method_counters;

   940   }

   941 

   942   bool   is_not_c1_compilable() const         { return access_flags().is_not_c1_compilable();  }

   943   void  set_not_c1_compilable()               {       _access_flags.set_not_c1_compilable();   }

   944   void clear_not_c1_compilable()              {       _access_flags.clear_not_c1_compilable(); }

   945   bool   is_not_c2_compilable() const         { return access_flags().is_not_c2_compilable();  }

   946   void  set_not_c2_compilable()               {       _access_flags.set_not_c2_compilable();   }

   947   void clear_not_c2_compilable()              {       _access_flags.clear_not_c2_compilable(); }

   948 

   949   bool    is_not_c1_osr_compilable() const    { return is_not_c1_compilable(); }  // don't waste an accessFlags bit

   950   void   set_not_c1_osr_compilable()          {       set_not_c1_compilable(); }  // don't waste an accessFlags bit

   951   void clear_not_c1_osr_compilable()          {     clear_not_c1_compilable(); }  // don't waste an accessFlags bit

   952   bool   is_not_c2_osr_compilable() const     { return access_flags().is_not_c2_osr_compilable();  }

   953   void  set_not_c2_osr_compilable()           {       _access_flags.set_not_c2_osr_compilable();   }

   954   void clear_not_c2_osr_compilable()          {       _access_flags.clear_not_c2_osr_compilable(); }

   955 

   956   // Background compilation support

   957   bool queued_for_compilation() const  { return access_flags().queued_for_compilation(); }

   958   void set_queued_for_compilation()    { _access_flags.set_queued_for_compilation();     }

   959   void clear_queued_for_compilation()  { _access_flags.clear_queued_for_compilation();   }

   960 

   961   // Resolve all classes in signature, return 'true' if successful

   962   static bool load_signature_classes(const methodHandle& m, TRAPS);

   963 

   964   // Return if true if not all classes references in signature, including return type, has been loaded

   965   static bool has_unloaded_classes_in_signature(const methodHandle& m, TRAPS);

   966 

   967   // Printing

   968   void print_short_name(outputStream* st = tty); // prints as klassname::methodname; Exposed so field engineers can debug VM

   969 #if INCLUDE_JVMTI

   970   void print_name(outputStream* st = tty); // prints as "virtual void foo(int)"; exposed for TraceRedefineClasses

   971 #else

   972   void print_name(outputStream* st = tty)        PRODUCT_RETURN; // prints as "virtual void foo(int)"

   973 #endif

   974 

   975   // Helper routine used for method sorting

   976   static void sort_methods(Array<Method*>* methods, bool idempotent = false, bool set_idnums = true);

   977 

   978   // Deallocation function for redefine classes or if an error occurs

   979   void deallocate_contents(ClassLoaderData* loader_data);

   980 

   981   // Printing

   982 #ifndef PRODUCT

   983   void print_on(outputStream* st) const;

   984 #endif

   985   void print_value_on(outputStream* st) const;

   986   void print_linkage_flags(outputStream* st) PRODUCT_RETURN;

   987 

   988   const char* internal_name() const { return "{method}"; }

   989 

   990   // Check for valid method pointer

   991   static bool has_method_vptr(const void* ptr);

   992   bool is_valid_method() const;

   993 

   994   // Verify

   995   void verify() { verify_on(tty); }

   996   void verify_on(outputStream* st);

   997 

   998  private:

   999 

  1000   // Inlined elements

  1001   address* native_function_addr() const          { assert(is_native(), "must be native"); return (address*) (this+1); }

  1002   address* signature_handler_addr() const        { return native_function_addr() + 1; }

  1003 };

  1004 

  1005 

  1006 // Utility class for compressing line number tables

  1007 

  1008 class CompressedLineNumberWriteStream: public CompressedWriteStream {

  1009  private:

  1010   int _bci;

  1011   int _line;

  1012  public:

  1013   // Constructor

  1014   CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}

  1015   CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}

  1016 

  1017   // Write (bci, line number) pair to stream

  1018   void write_pair_regular(int bci_delta, int line_delta);

  1019 

  1020   inline void write_pair_inline(int bci, int line) {

  1021     int bci_delta = bci - _bci;

  1022     int line_delta = line - _line;

  1023     _bci = bci;

  1024     _line = line;

  1025     // Skip (0,0) deltas - they do not add information and conflict with terminator.

  1026     if (bci_delta == 0 && line_delta == 0) return;

  1027     // Check if bci is 5-bit and line number 3-bit unsigned.

  1028     if (((bci_delta & ~0x1F) == 0) && ((line_delta & ~0x7) == 0)) {

  1029       // Compress into single byte.

  1030       jubyte value = ((jubyte) bci_delta << 3) | (jubyte) line_delta;

  1031       // Check that value doesn't match escape character.

  1032       if (value != 0xFF) {

  1033         write_byte(value);

  1034         return;

  1035       }

  1036     }

  1037     write_pair_regular(bci_delta, line_delta);

  1038   }

  1039 

  1040 // Windows AMD64 + Apr 2005 PSDK with /O2 generates bad code for write_pair.

  1041 // Disabling optimization doesn't work for methods in header files

  1042 // so we force it to call through the non-optimized version in the .cpp.

  1043 // It's gross, but it's the only way we can ensure that all callers are

  1044 // fixed.  _MSC_VER is defined by the windows compiler

  1045 #if defined(_M_AMD64) && _MSC_VER >= 1400

  1046   void write_pair(int bci, int line);

  1047 #else

  1048   void write_pair(int bci, int line) { write_pair_inline(bci, line); }

  1049 #endif

  1050 

  1051   // Write end-of-stream marker

  1052   void write_terminator()                        { write_byte(0); }

  1053 };

  1054 

  1055 

  1056 // Utility class for decompressing line number tables

  1057 

  1058 class CompressedLineNumberReadStream: public CompressedReadStream {

  1059  private:

  1060   int _bci;

  1061   int _line;

  1062  public:

  1063   // Constructor

  1064   CompressedLineNumberReadStream(u_char* buffer);

  1065   // Read (bci, line number) pair from stream. Returns false at end-of-stream.

  1066   bool read_pair();

  1067   // Accessing bci and line number (after calling read_pair)

  1068   int bci() const                               { return _bci; }

  1069   int line() const                              { return _line; }

  1070 };

  1071 

  1072 

  1073 #if INCLUDE_JVMTI

  1074 

  1075 /// Fast Breakpoints.

  1076 

  1077 // If this structure gets more complicated (because bpts get numerous),

  1078 // move it into its own header.

  1079 

  1080 // There is presently no provision for concurrent access

  1081 // to breakpoint lists, which is only OK for JVMTI because

  1082 // breakpoints are written only at safepoints, and are read

  1083 // concurrently only outside of safepoints.

  1084 

  1085 class BreakpointInfo : public CHeapObj<mtClass> {

  1086   friend class VMStructs;

  1087  private:

  1088   Bytecodes::Code  _orig_bytecode;

  1089   int              _bci;

  1090   u2               _name_index;       // of method

  1091   u2               _signature_index;  // of method

  1092   BreakpointInfo*  _next;             // simple storage allocation

  1093 

  1094  public:

  1095   BreakpointInfo(Method* m, int bci);

  1096 

  1097   // accessors

  1098   Bytecodes::Code orig_bytecode()                     { return _orig_bytecode; }

  1099   void        set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }

  1100   int         bci()                                   { return _bci; }

  1101 

  1102   BreakpointInfo*          next() const               { return _next; }

  1103   void                 set_next(BreakpointInfo* n)    { _next = n; }

  1104 

  1105   // helps for searchers

  1106   bool match(const Method* m, int bci) {

  1107     return bci == _bci && match(m);

  1108   }

  1109 

  1110   bool match(const Method* m) {

  1111     return _name_index == m->name_index() &&

  1112       _signature_index == m->signature_index();

  1113   }

  1114 

  1115   void set(Method* method);

  1116   void clear(Method* method);

  1117 };

  1118 

  1119 #endif // INCLUDE_JVMTI

  1120 

  1121 // Utility class for access exception handlers

  1122 class ExceptionTable : public StackObj {

  1123  private:

  1124   ExceptionTableElement* _table;

  1125   u2  _length;

  1126 

  1127  public:

  1128   ExceptionTable(const Method* m) {

  1129     if (m->has_exception_handler()) {

  1130       _table = m->exception_table_start();

  1131       _length = m->exception_table_length();

  1132     } else {

  1133       _table = NULL;

  1134       _length = 0;