1 /*
   2  * Copyright (c) 1997, 2016, 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/oopMap.hpp"
  31 #include "interpreter/invocationCounter.hpp"
  32 #include "oops/annotations.hpp"
  33 #include "oops/constantPool.hpp"
  34 #include "oops/methodCounters.hpp"
  35 #include "oops/instanceKlass.hpp"
  36 #include "oops/oop.hpp"
  37 #include "oops/typeArrayOop.hpp"
  38 #include "utilities/accessFlags.hpp"
  39 #include "utilities/growableArray.hpp"
  40 
  41 // A Method represents a Java method.
  42 //
  43 // Note that most applications load thousands of methods, so keeping the size of this
  44 // class small has a big impact on footprint.
  45 //
  46 // Note that native_function and signature_handler have to be at fixed offsets
  47 // (required by the interpreter)
  48 //
  49 //  Method embedded field layout (after declared fields):
  50 //   [EMBEDDED native_function       (present only if native) ]
  51 //   [EMBEDDED signature_handler     (present only if native) ]
  52 
  53 class CheckedExceptionElement;
  54 class LocalVariableTableElement;
  55 class AdapterHandlerEntry;
  56 class MethodData;
  57 class MethodCounters;
  58 class ConstMethod;
  59 class InlineTableSizes;
  60 class KlassSizeStats;
  61 class CompiledMethod;
  62 
  63 class Method : public Metadata {
  64  friend class VMStructs;
  65  friend class JVMCIVMStructs;
  66  private:
  67   ConstMethod*      _constMethod;                // Method read-only data.
  68   MethodData*       _method_data;
  69   MethodCounters*   _method_counters;
  70   AccessFlags       _access_flags;               // Access flags
  71   int               _vtable_index;               // vtable index of this method (see VtableIndexFlag)
  72                                                  // note: can have vtables with >2**16 elements (because of inheritance)
  73   u2                _intrinsic_id;               // vmSymbols::intrinsic_id (0 == _none)
  74 
  75   // Flags
  76   enum Flags {
  77     _jfr_towrite           = 1 << 0,
  78     _caller_sensitive      = 1 << 1,
  79     _force_inline          = 1 << 2,
  80     _dont_inline           = 1 << 3,
  81     _hidden                = 1 << 4,
  82     _has_injected_profile  = 1 << 5,
  83     _running_emcp          = 1 << 6,
  84     _intrinsic_candidate   = 1 << 7,
  85     _reserved_stack_access = 1 << 8
  86   };
  87   mutable u2 _flags;
  88 
  89 #ifndef PRODUCT
  90   int               _compiled_invocation_count;  // Number of nmethod invocations so far (for perf. debugging)
  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->entry_point() : _adapter->c2i_entry()
  97   // The entry point for calling both from and to compiled code is
  98   // "_code->entry_point()".  Because of tiered compilation and de-opt, this
  99   // field can come and go.  It can transition from NULL to not-null at any
 100   // time (whenever a compile completes).  It can transition from not-null to
 101   // NULL only at safepoints (because of a de-opt).
 102   CompiledMethod* volatile _code;                       // Points to the corresponding piece of native code
 103   volatile address           _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
 104 
 105   // Constructor
 106   Method(ConstMethod* xconst, AccessFlags access_flags);
 107  public:
 108 
 109   static Method* allocate(ClassLoaderData* loader_data,
 110                           int byte_code_size,
 111                           AccessFlags access_flags,
 112                           InlineTableSizes* sizes,
 113                           ConstMethod::MethodType method_type,
 114                           TRAPS);
 115 
 116   // CDS and vtbl checking can create an empty Method to get vtbl pointer.
 117   Method(){}
 118 
 119   // The Method vtable is restored by this call when the Method is in the
 120   // shared archive.  See patch_klass_vtables() in metaspaceShared.cpp for
 121   // all the gory details.  SA, dtrace and pstack helpers distinguish metadata
 122   // by their vtable.
 123   void restore_vtable() { guarantee(is_method(), "vtable restored by this call"); }
 124   bool is_method() const volatile { return true; }
 125 
 126   void restore_unshareable_info(TRAPS);
 127 
 128   // accessors for instance variables
 129 
 130   ConstMethod* constMethod() const             { return _constMethod; }
 131   void set_constMethod(ConstMethod* xconst)    { _constMethod = xconst; }
 132 
 133 
 134   static address make_adapters(methodHandle mh, TRAPS);
 135   volatile address from_compiled_entry() const   { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }
 136   volatile address from_compiled_entry_no_trampoline() const;
 137   volatile address from_interpreted_entry() const{ return (address)OrderAccess::load_ptr_acquire(&_from_interpreted_entry); }
 138 
 139   // access flag
 140   AccessFlags access_flags() const               { return _access_flags;  }
 141   void set_access_flags(AccessFlags flags)       { _access_flags = flags; }
 142 
 143   // name
 144   Symbol* name() const                           { return constants()->symbol_at(name_index()); }
 145   int name_index() const                         { return constMethod()->name_index();         }
 146   void set_name_index(int index)                 { constMethod()->set_name_index(index);       }
 147 
 148   // signature
 149   Symbol* signature() const                      { return constants()->symbol_at(signature_index()); }
 150   int signature_index() const                    { return constMethod()->signature_index();         }
 151   void set_signature_index(int index)            { constMethod()->set_signature_index(index);       }
 152 
 153   // generics support
 154   Symbol* generic_signature() const              { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : (Symbol*)NULL); }
 155   int generic_signature_index() const            { return constMethod()->generic_signature_index(); }
 156   void set_generic_signature_index(int index)    { constMethod()->set_generic_signature_index(index); }
 157 
 158   // annotations support
 159   AnnotationArray* annotations() const           {
 160     return constMethod()->method_annotations();
 161   }
 162   AnnotationArray* parameter_annotations() const {
 163     return constMethod()->parameter_annotations();
 164   }
 165   AnnotationArray* annotation_default() const    {
 166     return constMethod()->default_annotations();
 167   }
 168   AnnotationArray* type_annotations() const      {
 169     return constMethod()->type_annotations();
 170   }
 171 
 172   // Helper routine: get klass name + "." + method name + signature as
 173   // C string, for the purpose of providing more useful NoSuchMethodErrors
 174   // and fatal error handling. The string is allocated in resource
 175   // area if a buffer is not provided by the caller.
 176   char* name_and_sig_as_C_string() const;
 177   char* name_and_sig_as_C_string(char* buf, int size) const;
 178 
 179   // Static routine in the situations we don't have a Method*
 180   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
 181   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
 182 
 183   Bytecodes::Code java_code_at(int bci) const {
 184     return Bytecodes::java_code_at(this, bcp_from(bci));
 185   }
 186   Bytecodes::Code code_at(int bci) const {
 187     return Bytecodes::code_at(this, bcp_from(bci));
 188   }
 189 
 190   // JVMTI breakpoints
 191 #if !INCLUDE_JVMTI
 192   Bytecodes::Code orig_bytecode_at(int bci) const {
 193     ShouldNotReachHere();
 194     return Bytecodes::_shouldnotreachhere;
 195   }
 196   void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
 197     ShouldNotReachHere();
 198   };
 199   u2   number_of_breakpoints() const {return 0;}
 200 #else // !INCLUDE_JVMTI
 201   Bytecodes::Code orig_bytecode_at(int bci) const;
 202   void set_orig_bytecode_at(int bci, Bytecodes::Code code);
 203   void set_breakpoint(int bci);
 204   void clear_breakpoint(int bci);
 205   void clear_all_breakpoints();
 206   // Tracking number of breakpoints, for fullspeed debugging.
 207   // Only mutated by VM thread.
 208   u2   number_of_breakpoints()             const {
 209     MethodCounters* mcs = method_counters();
 210     if (mcs == NULL) {
 211       return 0;
 212     } else {
 213       return mcs->number_of_breakpoints();
 214     }
 215   }
 216   void incr_number_of_breakpoints(TRAPS)         {
 217     MethodCounters* mcs = get_method_counters(CHECK);
 218     if (mcs != NULL) {
 219       mcs->incr_number_of_breakpoints();
 220     }
 221   }
 222   void decr_number_of_breakpoints(TRAPS)         {
 223     MethodCounters* mcs = get_method_counters(CHECK);
 224     if (mcs != NULL) {
 225       mcs->decr_number_of_breakpoints();
 226     }
 227   }
 228   // Initialization only
 229   void clear_number_of_breakpoints()             {
 230     MethodCounters* mcs = method_counters();
 231     if (mcs != NULL) {
 232       mcs->clear_number_of_breakpoints();
 233     }
 234   }
 235 #endif // !INCLUDE_JVMTI
 236 
 237   // index into InstanceKlass methods() array
 238   // note: also used by jfr
 239   u2 method_idnum() const           { return constMethod()->method_idnum(); }
 240   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }
 241 
 242   u2 orig_method_idnum() const           { return constMethod()->orig_method_idnum(); }
 243   void set_orig_method_idnum(u2 idnum)   { constMethod()->set_orig_method_idnum(idnum); }
 244 
 245   // code size
 246   int code_size() const                  { return constMethod()->code_size(); }
 247 
 248   // method size in words
 249   int method_size() const                { return sizeof(Method)/wordSize + is_native() ? 2 : 0; }
 250 
 251   // constant pool for Klass* holding this method
 252   ConstantPool* constants() const              { return constMethod()->constants(); }
 253   void set_constants(ConstantPool* c)          { constMethod()->set_constants(c); }
 254 
 255   // max stack
 256   // return original max stack size for method verification
 257   int  verifier_max_stack() const                { return constMethod()->max_stack(); }
 258   int           max_stack() const                { return constMethod()->max_stack() + extra_stack_entries(); }
 259   void      set_max_stack(int size)              {        constMethod()->set_max_stack(size); }
 260 
 261   // max locals
 262   int  max_locals() const                        { return constMethod()->max_locals(); }
 263   void set_max_locals(int size)                  { constMethod()->set_max_locals(size); }
 264 
 265   int highest_comp_level() const;
 266   void set_highest_comp_level(int level);
 267   int highest_osr_comp_level() const;
 268   void set_highest_osr_comp_level(int level);
 269 
 270 #if defined(COMPILER2) || INCLUDE_JVMCI
 271   // Count of times method was exited via exception while interpreting
 272   void interpreter_throwout_increment(TRAPS) {
 273     MethodCounters* mcs = get_method_counters(CHECK);
 274     if (mcs != NULL) {
 275       mcs->interpreter_throwout_increment();
 276     }
 277   }
 278 #endif
 279 
 280   int  interpreter_throwout_count() const        {
 281     MethodCounters* mcs = method_counters();
 282     if (mcs == NULL) {
 283       return 0;
 284     } else {
 285       return mcs->interpreter_throwout_count();
 286     }
 287   }
 288 
 289   // size of parameters
 290   int  size_of_parameters() const                { return constMethod()->size_of_parameters(); }
 291   void set_size_of_parameters(int size)          { constMethod()->set_size_of_parameters(size); }
 292 
 293   bool has_stackmap_table() const {
 294     return constMethod()->has_stackmap_table();
 295   }
 296 
 297   Array<u1>* stackmap_data() const {
 298     return constMethod()->stackmap_data();
 299   }
 300 
 301   void set_stackmap_data(Array<u1>* sd) {
 302     constMethod()->set_stackmap_data(sd);
 303   }
 304 
 305   // exception handler table
 306   bool has_exception_handler() const
 307                              { return constMethod()->has_exception_handler(); }
 308   int exception_table_length() const
 309                              { return constMethod()->exception_table_length(); }
 310   ExceptionTableElement* exception_table_start() const
 311                              { return constMethod()->exception_table_start(); }
 312 
 313   // Finds the first entry point bci of an exception handler for an
 314   // exception of klass ex_klass thrown at throw_bci. A value of NULL
 315   // for ex_klass indicates that the exception klass is not known; in
 316   // this case it matches any constraint class. Returns -1 if the
 317   // exception cannot be handled in this method. The handler
 318   // constraint classes are loaded if necessary. Note that this may
 319   // throw an exception if loading of the constraint classes causes
 320   // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
 321   // If an exception is thrown, returns the bci of the
 322   // exception handler which caused the exception to be thrown, which
 323   // is needed for proper retries. See, for example,
 324   // InterpreterRuntime::exception_handler_for_exception.
 325   static int fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS);
 326 
 327   // method data access
 328   MethodData* method_data() const              {
 329     return _method_data;
 330   }
 331 
 332   void set_method_data(MethodData* data)       {
 333     // The store into method must be released. On platforms without
 334     // total store order (TSO) the reference may become visible before
 335     // the initialization of data otherwise.
 336     OrderAccess::release_store_ptr((volatile void *)&_method_data, data);
 337   }
 338 
 339   MethodCounters* method_counters() const {
 340     return _method_counters;
 341   }
 342 
 343   void clear_method_counters() {
 344     _method_counters = NULL;
 345   }
 346 
 347   bool init_method_counters(MethodCounters* counters) {
 348     // Try to install a pointer to MethodCounters, return true on success.
 349     return Atomic::cmpxchg_ptr(counters, (volatile void*)&_method_counters, NULL) == NULL;
 350   }
 351 
 352 #ifdef TIERED
 353   // We are reusing interpreter_invocation_count as a holder for the previous event count!
 354   // We can do that since interpreter_invocation_count is not used in tiered.
 355   int prev_event_count() const                   {
 356     if (method_counters() == NULL) {
 357       return 0;
 358     } else {
 359       return method_counters()->interpreter_invocation_count();
 360     }
 361   }
 362   void set_prev_event_count(int count) {
 363     MethodCounters* mcs = method_counters();
 364     if (mcs != NULL) {
 365       mcs->set_interpreter_invocation_count(count);
 366     }
 367   }
 368   jlong prev_time() const                        {
 369     MethodCounters* mcs = method_counters();
 370     return mcs == NULL ? 0 : mcs->prev_time();
 371   }
 372   void set_prev_time(jlong time) {
 373     MethodCounters* mcs = method_counters();
 374     if (mcs != NULL) {
 375       mcs->set_prev_time(time);
 376     }
 377   }
 378   float rate() const                             {
 379     MethodCounters* mcs = method_counters();
 380     return mcs == NULL ? 0 : mcs->rate();
 381   }
 382   void set_rate(float rate) {
 383     MethodCounters* mcs = method_counters();
 384     if (mcs != NULL) {
 385       mcs->set_rate(rate);
 386     }
 387   }
 388 #endif
 389   int nmethod_age() const {
 390     if (method_counters() == NULL) {
 391       return INT_MAX;
 392     } else {
 393       return method_counters()->nmethod_age();
 394     }
 395   }
 396 
 397   int invocation_count();
 398   int backedge_count();
 399 
 400   bool was_executed_more_than(int n);
 401   bool was_never_executed()                      { return !was_executed_more_than(0); }
 402 
 403   static void build_interpreter_method_data(const methodHandle& method, TRAPS);
 404 
 405   static MethodCounters* build_method_counters(Method* m, TRAPS);
 406 
 407   int interpreter_invocation_count() {
 408     if (TieredCompilation) {
 409       return invocation_count();
 410     } else {
 411       MethodCounters* mcs = method_counters();
 412       return (mcs == NULL) ? 0 : mcs->interpreter_invocation_count();
 413     }
 414   }
 415 #if defined(COMPILER2) || INCLUDE_JVMCI
 416   int increment_interpreter_invocation_count(TRAPS) {
 417     if (TieredCompilation) ShouldNotReachHere();
 418     MethodCounters* mcs = get_method_counters(CHECK_0);
 419     return (mcs == NULL) ? 0 : mcs->increment_interpreter_invocation_count();
 420   }
 421 #endif
 422 
 423 #ifndef PRODUCT
 424   int  compiled_invocation_count() const         { return _compiled_invocation_count;  }
 425   void set_compiled_invocation_count(int count)  { _compiled_invocation_count = count; }
 426 #else
 427   // for PrintMethodData in a product build
 428   int  compiled_invocation_count() const         { return 0;  }
 429 #endif // not PRODUCT
 430 
 431   // Clear (non-shared space) pointers which could not be relevant
 432   // if this (shared) method were mapped into another JVM.
 433   void remove_unshareable_info();
 434 
 435   // nmethod/verified compiler entry
 436   address verified_code_entry();
 437   bool check_code() const;      // Not inline to avoid circular ref
 438   CompiledMethod* volatile code() const                 { assert( check_code(), "" ); return (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code); }
 439   void clear_code();            // Clear out any compiled code
 440   static void set_code(methodHandle mh, CompiledMethod* code);
 441   void set_adapter_entry(AdapterHandlerEntry* adapter) {
 442     constMethod()->set_adapter_entry(adapter);
 443   }
 444   void update_adapter_trampoline(AdapterHandlerEntry* adapter) {
 445     constMethod()->update_adapter_trampoline(adapter);
 446   }
 447 
 448   address get_i2c_entry();
 449   address get_c2i_entry();
 450   address get_c2i_unverified_entry();
 451   AdapterHandlerEntry* adapter() const {
 452     return constMethod()->adapter();
 453   }
 454   // setup entry points
 455   void link_method(const methodHandle& method, TRAPS);
 456   // clear entry points. Used by sharing code during dump time
 457   void unlink_method() NOT_CDS_RETURN;
 458 
 459   // vtable index
 460   enum VtableIndexFlag {
 461     // Valid vtable indexes are non-negative (>= 0).
 462     // These few negative values are used as sentinels.
 463     itable_index_max        = -10, // first itable index, growing downward
 464     pending_itable_index    = -9,  // itable index will be assigned
 465     invalid_vtable_index    = -4,  // distinct from any valid vtable index
 466     garbage_vtable_index    = -3,  // not yet linked; no vtable layout yet
 467     nonvirtual_vtable_index = -2   // there is no need for vtable dispatch
 468     // 6330203 Note:  Do not use -1, which was overloaded with many meanings.
 469   };
 470   DEBUG_ONLY(bool valid_vtable_index() const     { return _vtable_index >= nonvirtual_vtable_index; })
 471   bool has_vtable_index() const                  { return _vtable_index >= 0; }
 472   int  vtable_index() const                      { return _vtable_index; }
 473   void set_vtable_index(int index)               { _vtable_index = index; }
 474   DEBUG_ONLY(bool valid_itable_index() const     { return _vtable_index <= pending_itable_index; })
 475   bool has_itable_index() const                  { return _vtable_index <= itable_index_max; }
 476   int  itable_index() const                      { assert(valid_itable_index(), "");
 477                                                    return itable_index_max - _vtable_index; }
 478   void set_itable_index(int index)               { _vtable_index = itable_index_max - index; assert(valid_itable_index(), ""); }
 479 
 480   // interpreter entry
 481   address interpreter_entry() const              { return _i2i_entry; }
 482   // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
 483   void set_interpreter_entry(address entry) {
 484     assert(!is_shared(), "shared method's interpreter entry should not be changed at run time");
 485     if (_i2i_entry != entry) {
 486       _i2i_entry = entry;
 487     }
 488     if (_from_interpreted_entry != entry) {
 489       _from_interpreted_entry = entry;
 490     }
 491   }
 492 
 493   // native function (used for native methods only)
 494   enum {
 495     native_bind_event_is_interesting = true
 496   };
 497   address native_function() const                { return *(native_function_addr()); }
 498   address critical_native_function();
 499 
 500   // Must specify a real function (not NULL).
 501   // Use clear_native_function() to unregister.
 502   void set_native_function(address function, bool post_event_flag);
 503   bool has_native_function() const;
 504   void clear_native_function();
 505 
 506   // signature handler (used for native methods only)
 507   address signature_handler() const              { return *(signature_handler_addr()); }
 508   void set_signature_handler(address handler);
 509 
 510   // Interpreter oopmap support
 511   void mask_for(int bci, InterpreterOopMap* mask);
 512 
 513   // operations on invocation counter
 514   void print_invocation_count();
 515 
 516   // byte codes
 517   void    set_code(address code)      { return constMethod()->set_code(code); }
 518   address code_base() const           { return constMethod()->code_base(); }
 519   bool    contains(address bcp) const { return constMethod()->contains(bcp); }
 520 
 521   // prints byte codes
 522   void print_codes() const            { print_codes_on(tty); }
 523   void print_codes_on(outputStream* st) const;
 524   void print_codes_on(int from, int to, outputStream* st) const;
 525 
 526   // method parameters
 527   bool has_method_parameters() const
 528                          { return constMethod()->has_method_parameters(); }
 529   int method_parameters_length() const
 530                          { return constMethod()->method_parameters_length(); }
 531   MethodParametersElement* method_parameters_start() const
 532                           { return constMethod()->method_parameters_start(); }
 533 
 534   // checked exceptions
 535   int checked_exceptions_length() const
 536                          { return constMethod()->checked_exceptions_length(); }
 537   CheckedExceptionElement* checked_exceptions_start() const
 538                           { return constMethod()->checked_exceptions_start(); }
 539 
 540   // localvariable table
 541   bool has_localvariable_table() const
 542                           { return constMethod()->has_localvariable_table(); }
 543   int localvariable_table_length() const
 544                         { return constMethod()->localvariable_table_length(); }
 545   LocalVariableTableElement* localvariable_table_start() const
 546                          { return constMethod()->localvariable_table_start(); }
 547 
 548   bool has_linenumber_table() const
 549                               { return constMethod()->has_linenumber_table(); }
 550   u_char* compressed_linenumber_table() const
 551                        { return constMethod()->compressed_linenumber_table(); }
 552 
 553   // method holder (the Klass* holding this method)
 554   InstanceKlass* method_holder() const         { return constants()->pool_holder(); }
 555 
 556   void compute_size_of_parameters(Thread *thread); // word size of parameters (receiver if any + arguments)
 557   Symbol* klass_name() const;                    // returns the name of the method holder
 558   BasicType result_type() const;                 // type of the method result
 559   bool is_returning_oop() const                  { BasicType r = result_type(); return (r == T_OBJECT || r == T_ARRAY); }
 560   bool is_returning_fp() const                   { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }
 561 
 562   // Checked exceptions thrown by this method (resolved to mirrors)
 563   objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
 564 
 565   // Access flags
 566   bool is_public() const                         { return access_flags().is_public();      }
 567   bool is_private() const                        { return access_flags().is_private();     }
 568   bool is_protected() const                      { return access_flags().is_protected();   }
 569   bool is_package_private() const                { return !is_public() && !is_private() && !is_protected(); }
 570   bool is_static() const                         { return access_flags().is_static();      }
 571   bool is_final() const                          { return access_flags().is_final();       }
 572   bool is_synchronized() const                   { return access_flags().is_synchronized();}
 573   bool is_native() const                         { return access_flags().is_native();      }
 574   bool is_abstract() const                       { return access_flags().is_abstract();    }
 575   bool is_strict() const                         { return access_flags().is_strict();      }
 576   bool is_synthetic() const                      { return access_flags().is_synthetic();   }
 577 
 578   // returns true if contains only return operation
 579   bool is_empty_method() const;
 580 
 581   // returns true if this is a vanilla constructor
 582   bool is_vanilla_constructor() const;
 583 
 584   // checks method and its method holder
 585   bool is_final_method() const;
 586   bool is_final_method(AccessFlags class_access_flags) const;
 587   bool is_default_method() const;
 588 
 589   // true if method needs no dynamic dispatch (final and/or no vtable entry)
 590   bool can_be_statically_bound() const;
 591   bool can_be_statically_bound(AccessFlags class_access_flags) const;
 592 
 593   // returns true if the method has any backward branches.
 594   bool has_loops() {
 595     return access_flags().loops_flag_init() ? access_flags().has_loops() : compute_has_loops_flag();
 596   };
 597 
 598   bool compute_has_loops_flag();
 599 
 600   bool has_jsrs() {
 601     return access_flags().has_jsrs();
 602   };
 603   void set_has_jsrs() {
 604     _access_flags.set_has_jsrs();
 605   }
 606 
 607   // returns true if the method has any monitors.
 608   bool has_monitors() const                      { return is_synchronized() || access_flags().has_monitor_bytecodes(); }
 609   bool has_monitor_bytecodes() const             { return access_flags().has_monitor_bytecodes(); }
 610 
 611   void set_has_monitor_bytecodes()               { _access_flags.set_has_monitor_bytecodes(); }
 612 
 613   // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
 614   // propererly nest in the method. It might return false, even though they actually nest properly, since the info.
 615   // has not been computed yet.
 616   bool guaranteed_monitor_matching() const       { return access_flags().is_monitor_matching(); }
 617   void set_guaranteed_monitor_matching()         { _access_flags.set_monitor_matching(); }
 618 
 619   // returns true if the method is an accessor function (setter/getter).
 620   bool is_accessor() const;
 621 
 622   // returns true if the method is a getter
 623   bool is_getter() const;
 624 
 625   // returns true if the method is a setter
 626   bool is_setter() const;
 627 
 628   // returns true if the method does nothing but return a constant of primitive type
 629   bool is_constant_getter() const;
 630 
 631   // returns true if the method is an initializer (<init> or <clinit>).
 632   bool is_initializer() const;
 633 
 634   // returns true if the method is static OR if the classfile version < 51
 635   bool has_valid_initializer_flags() const;
 636 
 637   // returns true if the method name is <clinit> and the method has
 638   // valid static initializer flags.
 639   bool is_static_initializer() const;
 640 
 641   // returns true if the method name is <init>
 642   bool is_object_initializer() const;
 643 
 644   // compiled code support
 645   // NOTE: code() is inherently racy as deopt can be clearing code
 646   // simultaneously. Use with caution.
 647   bool has_compiled_code() const                 { return code() != NULL; }
 648 
 649   // sizing
 650   static int header_size()                       { return sizeof(Method)/wordSize; }
 651   static int size(bool is_native);
 652   int size() const                               { return method_size(); }
 653 #if INCLUDE_SERVICES
 654   void collect_statistics(KlassSizeStats *sz) const;
 655 #endif
 656   void log_touched(TRAPS);
 657   static void print_touched_methods(outputStream* out);
 658 
 659   // interpreter support
 660   static ByteSize const_offset()                 { return byte_offset_of(Method, _constMethod       ); }
 661   static ByteSize access_flags_offset()          { return byte_offset_of(Method, _access_flags      ); }
 662   static ByteSize from_compiled_offset()         { return byte_offset_of(Method, _from_compiled_entry); }
 663   static ByteSize code_offset()                  { return byte_offset_of(Method, _code); }
 664   static ByteSize method_data_offset()           {
 665     return byte_offset_of(Method, _method_data);
 666   }
 667   static ByteSize method_counters_offset()       {
 668     return byte_offset_of(Method, _method_counters);
 669   }
 670 #ifndef PRODUCT
 671   static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
 672 #endif // not PRODUCT
 673   static ByteSize native_function_offset()       { return in_ByteSize(sizeof(Method));                 }
 674   static ByteSize from_interpreted_offset()      { return byte_offset_of(Method, _from_interpreted_entry ); }
 675   static ByteSize interpreter_entry_offset()     { return byte_offset_of(Method, _i2i_entry ); }
 676   static ByteSize signature_handler_offset()     { return in_ByteSize(sizeof(Method) + wordSize);      }
 677 
 678   // for code generation
 679   static int method_data_offset_in_bytes()       { return offset_of(Method, _method_data); }
 680   static int intrinsic_id_offset_in_bytes()      { return offset_of(Method, _intrinsic_id); }
 681   static int intrinsic_id_size_in_bytes()        { return sizeof(u2); }
 682 
 683   // Static methods that are used to implement member methods where an exposed this pointer
 684   // is needed due to possible GCs
 685   static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
 686 
 687   // Returns the byte code index from the byte code pointer
 688   int     bci_from(address bcp) const;
 689   address bcp_from(int bci) const;
 690   address bcp_from(address bcp) const;
 691   int validate_bci_from_bcp(address bcp) const;
 692   int validate_bci(int bci) const;
 693 
 694   // Returns the line number for a bci if debugging information for the method is prowided,
 695   // -1 is returned otherwise.
 696   int line_number_from_bci(int bci) const;
 697 
 698   // Reflection support
 699   bool is_overridden_in(Klass* k) const;
 700 
 701   // Stack walking support
 702   bool is_ignored_by_security_stack_walk() const;
 703 
 704   // JSR 292 support
 705   bool is_method_handle_intrinsic() const;          // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
 706   bool is_compiled_lambda_form() const;             // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
 707   bool has_member_arg() const;                      // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
 708   static methodHandle make_method_handle_intrinsic(vmIntrinsics::ID iid, // _invokeBasic, _linkToVirtual
 709                                                    Symbol* signature, //anything at all
 710                                                    TRAPS);
 711   static Klass* check_non_bcp_klass(Klass* klass);
 712 
 713   enum {
 714     // How many extra stack entries for invokedynamic
 715     extra_stack_entries_for_jsr292 = 1
 716   };
 717 
 718   // this operates only on invoke methods:
 719   // presize interpreter frames for extra interpreter stack entries, if needed
 720   // Account for the extra appendix argument for invokehandle/invokedynamic
 721   static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
 722   static int extra_stack_words();  // = extra_stack_entries() * Interpreter::stackElementSize
 723 
 724   // RedefineClasses() support:
 725   bool is_old() const                               { return access_flags().is_old(); }
 726   void set_is_old()                                 { _access_flags.set_is_old(); }
 727   bool is_obsolete() const                          { return access_flags().is_obsolete(); }
 728   void set_is_obsolete()                            { _access_flags.set_is_obsolete(); }
 729   bool is_deleted() const                           { return access_flags().is_deleted(); }
 730   void set_is_deleted()                             { _access_flags.set_is_deleted(); }
 731 
 732   bool is_running_emcp() const {
 733     // EMCP methods are old but not obsolete or deleted. Equivalent
 734     // Modulo Constant Pool means the method is equivalent except
 735     // the constant pool and instructions that access the constant
 736     // pool might be different.
 737     // If a breakpoint is set in a redefined method, its EMCP methods that are
 738     // still running must have a breakpoint also.
 739     return (_flags & _running_emcp) != 0;
 740   }
 741 
 742   void set_running_emcp(bool x) {
 743     _flags = x ? (_flags | _running_emcp) : (_flags & ~_running_emcp);
 744   }
 745 
 746   bool on_stack() const                             { return access_flags().on_stack(); }
 747   void set_on_stack(const bool value);
 748 
 749   // see the definition in Method*.cpp for the gory details
 750   bool should_not_be_cached() const;
 751 
 752   // JVMTI Native method prefixing support:
 753   bool is_prefixed_native() const                   { return access_flags().is_prefixed_native(); }
 754   void set_is_prefixed_native()                     { _access_flags.set_is_prefixed_native(); }
 755 
 756   // Rewriting support
 757   static methodHandle clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
 758                                           u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
 759 
 760   // jmethodID handling
 761   // Because the useful life-span of a jmethodID cannot be determined,
 762   // once created they are never reclaimed.  The methods to which they refer,
 763   // however, can be GC'ed away if the class is unloaded or if the method is
 764   // made obsolete or deleted -- in these cases, the jmethodID
 765   // refers to NULL (as is the case for any weak reference).
 766   static jmethodID make_jmethod_id(ClassLoaderData* loader_data, Method* mh);
 767   static void destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID mid);
 768 
 769   // Ensure there is enough capacity in the internal tracking data
 770   // structures to hold the number of jmethodIDs you plan to generate.
 771   // This saves substantial time doing allocations.
 772   static void ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity);
 773 
 774   // Use resolve_jmethod_id() in situations where the caller is expected
 775   // to provide a valid jmethodID; the only sanity checks are in asserts;
 776   // result guaranteed not to be NULL.
 777   inline static Method* resolve_jmethod_id(jmethodID mid) {
 778     assert(mid != NULL, "JNI method id should not be null");
 779     return *((Method**)mid);
 780   }
 781 
 782   // Use checked_resolve_jmethod_id() in situations where the caller
 783   // should provide a valid jmethodID, but might not. NULL is returned
 784   // when the jmethodID does not refer to a valid method.
 785   static Method* checked_resolve_jmethod_id(jmethodID mid);
 786 
 787   static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
 788   static bool is_method_id(jmethodID mid);
 789 
 790   // Clear methods
 791   static void clear_jmethod_ids(ClassLoaderData* loader_data);
 792   static void print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
 793 
 794   // Get this method's jmethodID -- allocate if it doesn't exist
 795   jmethodID jmethod_id()                            { methodHandle this_h(this);
 796                                                       return InstanceKlass::get_jmethod_id(method_holder(), this_h); }
 797 
 798   // Lookup the jmethodID for this method.  Return NULL if not found.
 799   // NOTE that this function can be called from a signal handler
 800   // (see AsyncGetCallTrace support for Forte Analyzer) and this
 801   // needs to be async-safe. No allocation should be done and
 802   // so handles are not used to avoid deadlock.
 803   jmethodID find_jmethod_id_or_null()               { return method_holder()->jmethod_id_or_null(this); }
 804 
 805   // Support for inlining of intrinsic methods
 806   vmIntrinsics::ID intrinsic_id() const          { return (vmIntrinsics::ID) _intrinsic_id;           }
 807   void     set_intrinsic_id(vmIntrinsics::ID id) {                           _intrinsic_id = (u2) id; }
 808 
 809   // Helper routines for intrinsic_id() and vmIntrinsics::method().
 810   void init_intrinsic_id();     // updates from _none if a match
 811   static vmSymbols::SID klass_id_for_intrinsics(const Klass* holder);
 812 
 813   bool jfr_towrite() const {
 814     return (_flags & _jfr_towrite) != 0;
 815   }
 816   void set_jfr_towrite(bool x) const {
 817     _flags = x ? (_flags | _jfr_towrite) : (_flags & ~_jfr_towrite);
 818   }
 819 
 820   bool caller_sensitive() {
 821     return (_flags & _caller_sensitive) != 0;
 822   }
 823   void set_caller_sensitive(bool x) {
 824     _flags = x ? (_flags | _caller_sensitive) : (_flags & ~_caller_sensitive);
 825   }
 826 
 827   bool force_inline() {
 828     return (_flags & _force_inline) != 0;
 829   }
 830   void set_force_inline(bool x) {
 831     _flags = x ? (_flags | _force_inline) : (_flags & ~_force_inline);
 832   }
 833 
 834   bool dont_inline() {
 835     return (_flags & _dont_inline) != 0;
 836   }
 837   void set_dont_inline(bool x) {
 838     _flags = x ? (_flags | _dont_inline) : (_flags & ~_dont_inline);
 839   }
 840 
 841   bool is_hidden() {
 842     return (_flags & _hidden) != 0;
 843   }
 844   void set_hidden(bool x) {
 845     _flags = x ? (_flags | _hidden) : (_flags & ~_hidden);
 846   }
 847 
 848   bool intrinsic_candidate() {
 849     return (_flags & _intrinsic_candidate) != 0;
 850   }
 851   void set_intrinsic_candidate(bool x) {
 852     _flags = x ? (_flags | _intrinsic_candidate) : (_flags & ~_intrinsic_candidate);
 853   }
 854 
 855   bool has_injected_profile() {
 856     return (_flags & _has_injected_profile) != 0;
 857   }
 858   void set_has_injected_profile(bool x) {
 859     _flags = x ? (_flags | _has_injected_profile) : (_flags & ~_has_injected_profile);
 860   }
 861 
 862   bool has_reserved_stack_access() {
 863     return (_flags & _reserved_stack_access) != 0;
 864   }
 865 
 866   void set_has_reserved_stack_access(bool x) {
 867     _flags = x ? (_flags | _reserved_stack_access) : (_flags & ~_reserved_stack_access);
 868   }
 869 
 870   ConstMethod::MethodType method_type() const {
 871       return _constMethod->method_type();
 872   }
 873   bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
 874 
 875   // On-stack replacement support
 876   bool has_osr_nmethod(int level, bool match_level) {
 877    return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != NULL;
 878   }
 879 
 880   int mark_osr_nmethods() {
 881     return method_holder()->mark_osr_nmethods(this);
 882   }
 883 
 884   nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
 885     return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
 886   }
 887 
 888   // Inline cache support
 889   void cleanup_inline_caches();
 890 
 891   // Find if klass for method is loaded
 892   bool is_klass_loaded_by_klass_index(int klass_index) const;
 893   bool is_klass_loaded(int refinfo_index, bool must_be_resolved = false) const;
 894 
 895   // Indicates whether compilation failed earlier for this method, or
 896   // whether it is not compilable for another reason like having a
 897   // breakpoint set in it.
 898   bool  is_not_compilable(int comp_level = CompLevel_any) const;
 899   void set_not_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 900   void set_not_compilable_quietly(int comp_level = CompLevel_all) {
 901     set_not_compilable(comp_level, false);
 902   }
 903   bool  is_not_osr_compilable(int comp_level = CompLevel_any) const;
 904   void set_not_osr_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 905   void set_not_osr_compilable_quietly(int comp_level = CompLevel_all) {
 906     set_not_osr_compilable(comp_level, false);
 907   }
 908   bool is_always_compilable() const;
 909 
 910  private:
 911   void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
 912 
 913  public:
 914   MethodCounters* get_method_counters(TRAPS) {
 915     if (_method_counters == NULL) {
 916       build_method_counters(this, CHECK_AND_CLEAR_NULL);
 917     }
 918     return _method_counters;
 919   }
 920 
 921   bool   is_not_c1_compilable() const         { return access_flags().is_not_c1_compilable();  }
 922   void  set_not_c1_compilable()               {       _access_flags.set_not_c1_compilable();   }
 923   void clear_not_c1_compilable()              {       _access_flags.clear_not_c1_compilable(); }
 924   bool   is_not_c2_compilable() const         { return access_flags().is_not_c2_compilable();  }
 925   void  set_not_c2_compilable()               {       _access_flags.set_not_c2_compilable();   }
 926   void clear_not_c2_compilable()              {       _access_flags.clear_not_c2_compilable(); }
 927 
 928   bool    is_not_c1_osr_compilable() const    { return is_not_c1_compilable(); }  // don't waste an accessFlags bit
 929   void   set_not_c1_osr_compilable()          {       set_not_c1_compilable(); }  // don't waste an accessFlags bit
 930   void clear_not_c1_osr_compilable()          {     clear_not_c1_compilable(); }  // don't waste an accessFlags bit
 931   bool   is_not_c2_osr_compilable() const     { return access_flags().is_not_c2_osr_compilable();  }
 932   void  set_not_c2_osr_compilable()           {       _access_flags.set_not_c2_osr_compilable();   }
 933   void clear_not_c2_osr_compilable()          {       _access_flags.clear_not_c2_osr_compilable(); }
 934 
 935   // Background compilation support
 936   bool queued_for_compilation() const  { return access_flags().queued_for_compilation(); }
 937   void set_queued_for_compilation()    { _access_flags.set_queued_for_compilation();     }
 938   void clear_queued_for_compilation()  { _access_flags.clear_queued_for_compilation();   }
 939 
 940   // Resolve all classes in signature, return 'true' if successful
 941   static bool load_signature_classes(methodHandle m, TRAPS);
 942 
 943   // Return if true if not all classes references in signature, including return type, has been loaded
 944   static bool has_unloaded_classes_in_signature(methodHandle m, TRAPS);
 945 
 946   // Printing
 947   void print_short_name(outputStream* st = tty); // prints as klassname::methodname; Exposed so field engineers can debug VM
 948 #if INCLUDE_JVMTI
 949   void print_name(outputStream* st = tty); // prints as "virtual void foo(int)"; exposed for TraceRedefineClasses
 950 #else
 951   void print_name(outputStream* st = tty)        PRODUCT_RETURN; // prints as "virtual void foo(int)"
 952 #endif
 953 
 954   // Helper routine used for method sorting
 955   static void sort_methods(Array<Method*>* methods, bool idempotent = false, bool set_idnums = true);
 956 
 957   // Deallocation function for redefine classes or if an error occurs
 958   void deallocate_contents(ClassLoaderData* loader_data);
 959 
 960   // Printing
 961 #ifndef PRODUCT
 962   void print_on(outputStream* st) const;
 963 #endif
 964   void print_value_on(outputStream* st) const;
 965   void print_linkage_flags(outputStream* st) PRODUCT_RETURN;
 966 
 967   const char* internal_name() const { return "{method}"; }
 968 
 969   // Check for valid method pointer
 970   static bool has_method_vptr(const void* ptr);
 971   bool is_valid_method() const;
 972 
 973   // Verify
 974   void verify() { verify_on(tty); }
 975   void verify_on(outputStream* st);
 976 
 977  private:
 978 
 979   // Inlined elements
 980   address* native_function_addr() const          { assert(is_native(), "must be native"); return (address*) (this+1); }
 981   address* signature_handler_addr() const        { return native_function_addr() + 1; }
 982 };
 983 
 984 
 985 // Utility class for compressing line number tables
 986 
 987 class CompressedLineNumberWriteStream: public CompressedWriteStream {
 988  private:
 989   int _bci;
 990   int _line;
 991  public:
 992   // Constructor
 993   CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
 994   CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
 995 
 996   // Write (bci, line number) pair to stream
 997   void write_pair_regular(int bci_delta, int line_delta);
 998 
 999   inline void write_pair_inline(int bci, int line) {
1000     int bci_delta = bci - _bci;
1001     int line_delta = line - _line;
1002     _bci = bci;
1003     _line = line;
1004     // Skip (0,0) deltas - they do not add information and conflict with terminator.
1005     if (bci_delta == 0 && line_delta == 0) return;
1006     // Check if bci is 5-bit and line number 3-bit unsigned.
1007     if (((bci_delta & ~0x1F) == 0) && ((line_delta & ~0x7) == 0)) {
1008       // Compress into single byte.
1009       jubyte value = ((jubyte) bci_delta << 3) | (jubyte) line_delta;
1010       // Check that value doesn't match escape character.
1011       if (value != 0xFF) {
1012         write_byte(value);
1013         return;
1014       }
1015     }
1016     write_pair_regular(bci_delta, line_delta);
1017   }
1018 
1019 // Windows AMD64 + Apr 2005 PSDK with /O2 generates bad code for write_pair.
1020 // Disabling optimization doesn't work for methods in header files
1021 // so we force it to call through the non-optimized version in the .cpp.
1022 // It's gross, but it's the only way we can ensure that all callers are
1023 // fixed.  _MSC_VER is defined by the windows compiler
1024 #if defined(_M_AMD64) && _MSC_VER >= 1400
1025   void write_pair(int bci, int line);
1026 #else
1027   void write_pair(int bci, int line) { write_pair_inline(bci, line); }
1028 #endif
1029 
1030   // Write end-of-stream marker
1031   void write_terminator()                        { write_byte(0); }
1032 };
1033 
1034 
1035 // Utility class for decompressing line number tables
1036 
1037 class CompressedLineNumberReadStream: public CompressedReadStream {
1038  private:
1039   int _bci;
1040   int _line;
1041  public:
1042   // Constructor
1043   CompressedLineNumberReadStream(u_char* buffer);
1044   // Read (bci, line number) pair from stream. Returns false at end-of-stream.
1045   bool read_pair();
1046   // Accessing bci and line number (after calling read_pair)
1047   int bci() const                               { return _bci; }
1048   int line() const                              { return _line; }
1049 };
1050 
1051 
1052 #if INCLUDE_JVMTI
1053 
1054 /// Fast Breakpoints.
1055 
1056 // If this structure gets more complicated (because bpts get numerous),
1057 // move it into its own header.
1058 
1059 // There is presently no provision for concurrent access
1060 // to breakpoint lists, which is only OK for JVMTI because
1061 // breakpoints are written only at safepoints, and are read
1062 // concurrently only outside of safepoints.
1063 
1064 class BreakpointInfo : public CHeapObj<mtClass> {
1065   friend class VMStructs;
1066  private:
1067   Bytecodes::Code  _orig_bytecode;
1068   int              _bci;
1069   u2               _name_index;       // of method
1070   u2               _signature_index;  // of method
1071   BreakpointInfo*  _next;             // simple storage allocation
1072 
1073  public:
1074   BreakpointInfo(Method* m, int bci);
1075 
1076   // accessors
1077   Bytecodes::Code orig_bytecode()                     { return _orig_bytecode; }
1078   void        set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
1079   int         bci()                                   { return _bci; }
1080 
1081   BreakpointInfo*          next() const               { return _next; }
1082   void                 set_next(BreakpointInfo* n)    { _next = n; }
1083 
1084   // helps for searchers
1085   bool match(const Method* m, int bci) {
1086     return bci == _bci && match(m);
1087   }
1088 
1089   bool match(const Method* m) {
1090     return _name_index == m->name_index() &&
1091       _signature_index == m->signature_index();
1092   }
1093 
1094   void set(Method* method);
1095   void clear(Method* method);
1096 };
1097 
1098 #endif // INCLUDE_JVMTI
1099 
1100 // Utility class for access exception handlers
1101 class ExceptionTable : public StackObj {
1102  private:
1103   ExceptionTableElement* _table;
1104   u2  _length;
1105 
1106  public:
1107   ExceptionTable(const Method* m) {
1108     if (m->has_exception_handler()) {
1109       _table = m->exception_table_start();
1110       _length = m->exception_table_length();
1111     } else {
1112       _table = NULL;
1113       _length = 0;
1114     }
1115   }
1116 
1117   int length() const {
1118     return _length;
1119   }
1120 
1121   u2 start_pc(int idx) const {
1122     assert(idx < _length, "out of bounds");
1123     return _table[idx].start_pc;
1124   }
1125 
1126   void set_start_pc(int idx, u2 value) {
1127     assert(idx < _length, "out of bounds");
1128     _table[idx].start_pc = value;
1129   }
1130 
1131   u2 end_pc(int idx) const {
1132     assert(idx < _length, "out of bounds");
1133     return _table[idx].end_pc;
1134   }
1135 
1136   void set_end_pc(int idx, u2 value) {
1137     assert(idx < _length, "out of bounds");
1138     _table[idx].end_pc = value;
1139   }
1140 
1141   u2 handler_pc(int idx) const {
1142     assert(idx < _length, "out of bounds");
1143     return _table[idx].handler_pc;
1144   }
1145 
1146   void set_handler_pc(int idx, u2 value) {
1147     assert(idx < _length, "out of bounds");
1148     _table[idx].handler_pc = value;
1149   }
1150 
1151   u2 catch_type_index(int idx) const {
1152     assert(idx < _length, "out of bounds");
1153     return _table[idx].catch_type_index;
1154   }
1155 
1156   void set_catch_type_index(int idx, u2 value) {
1157     assert(idx < _length, "out of bounds");
1158     _table[idx].catch_type_index = value;
1159   }
1160 };
1161 
1162 #endif // SHARE_VM_OOPS_METHODOOP_HPP