1 /*
   2  * Copyright (c) 1997, 2014, 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 
  62 class Method : public Metadata {
  63  friend class VMStructs;
  64  private:
  65   ConstMethod*      _constMethod;                // Method read-only data.
  66   MethodData*       _method_data;
  67   MethodCounters*   _method_counters;
  68   AccessFlags       _access_flags;               // Access flags
  69   int               _vtable_index;               // vtable index of this method (see VtableIndexFlag)
  70                                                  // note: can have vtables with >2**16 elements (because of inheritance)
  71 #ifdef CC_INTERP
  72   int               _result_index;               // C++ interpreter needs for converting results to/from stack
  73 #endif
  74   u2                _method_size;                // size of this object
  75   u1                _intrinsic_id;               // vmSymbols::intrinsic_id (0 == _none)
  76 
  77   // Flags
  78   enum Flags {
  79     _jfr_towrite      = 1 << 0,
  80     _caller_sensitive = 1 << 1,
  81     _force_inline     = 1 << 2,
  82     _dont_inline      = 1 << 3,
  83     _hidden           = 1 << 4,
  84     _running_emcp     = 1 << 5
  85   };
  86   u1 _flags;
  87 
  88 #ifndef PRODUCT
  89   int               _compiled_invocation_count;  // Number of nmethod invocations so far (for perf. debugging)
  90 #endif
  91   // Entry point for calling both from and to the interpreter.
  92   address _i2i_entry;           // All-args-on-stack calling convention
  93   // Adapter blob (i2c/c2i) for this Method*. Set once when method is linked.
  94   AdapterHandlerEntry* _adapter;
  95   // Entry point for calling from compiled code, to compiled code if it exists
  96   // or else the interpreter.
  97   volatile address _from_compiled_entry;        // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
  98   // The entry point for calling both from and to compiled code is
  99   // "_code->entry_point()".  Because of tiered compilation and de-opt, this
 100   // field can come and go.  It can transition from NULL to not-null at any
 101   // time (whenever a compile completes).  It can transition from not-null to
 102   // NULL only at safepoints (because of a de-opt).
 103   nmethod* volatile _code;                       // Points to the corresponding piece of native code
 104   volatile address           _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
 105 
 106   // Constructor
 107   Method(ConstMethod* xconst, AccessFlags access_flags, int size);
 108  public:
 109 
 110   static Method* allocate(ClassLoaderData* loader_data,
 111                           int byte_code_size,
 112                           AccessFlags access_flags,
 113                           InlineTableSizes* sizes,
 114                           ConstMethod::MethodType method_type,
 115                           TRAPS);
 116 
 117   // CDS and vtbl checking can create an empty Method to get vtbl pointer.
 118   Method(){}
 119 
 120   // The Method vtable is restored by this call when the Method is in the
 121   // shared archive.  See patch_klass_vtables() in metaspaceShared.cpp for
 122   // all the gory details.  SA, dtrace and pstack helpers distinguish metadata
 123   // by their vtable.
 124   void restore_vtable() { guarantee(is_method(), "vtable restored by this call"); }
 125   bool is_method() const volatile { return true; }
 126 
 127   void restore_unshareable_info(TRAPS);
 128 
 129   // accessors for instance variables
 130 
 131   ConstMethod* constMethod() const             { return _constMethod; }
 132   void set_constMethod(ConstMethod* xconst)    { _constMethod = xconst; }
 133 
 134 
 135   static address make_adapters(methodHandle mh, TRAPS);
 136   volatile address from_compiled_entry() const   { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }
 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 #ifdef CC_INTERP
 173   void set_result_index(BasicType type);
 174   int  result_index()                            { return _result_index; }
 175 #endif
 176 
 177   // Helper routine: get klass name + "." + method name + signature as
 178   // C string, for the purpose of providing more useful NoSuchMethodErrors
 179   // and fatal error handling. The string is allocated in resource
 180   // area if a buffer is not provided by the caller.
 181   char* name_and_sig_as_C_string() const;
 182   char* name_and_sig_as_C_string(char* buf, int size) const;
 183 
 184   // Static routine in the situations we don't have a Method*
 185   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
 186   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
 187 
 188   Bytecodes::Code java_code_at(int bci) const {
 189     return Bytecodes::java_code_at(this, bcp_from(bci));
 190   }
 191   Bytecodes::Code code_at(int bci) const {
 192     return Bytecodes::code_at(this, bcp_from(bci));
 193   }
 194 
 195   // JVMTI breakpoints
 196   Bytecodes::Code orig_bytecode_at(int bci) const;
 197   void        set_orig_bytecode_at(int bci, Bytecodes::Code code);
 198   void set_breakpoint(int bci);
 199   void clear_breakpoint(int bci);
 200   void clear_all_breakpoints();
 201   // Tracking number of breakpoints, for fullspeed debugging.
 202   // Only mutated by VM thread.
 203   u2   number_of_breakpoints()             const {
 204     MethodCounters* mcs = method_counters();
 205     if (mcs == NULL) {
 206       return 0;
 207     } else {
 208       return mcs->number_of_breakpoints();
 209     }
 210   }
 211   void incr_number_of_breakpoints(TRAPS)         {
 212     MethodCounters* mcs = get_method_counters(CHECK);
 213     if (mcs != NULL) {
 214       mcs->incr_number_of_breakpoints();
 215     }
 216   }
 217   void decr_number_of_breakpoints(TRAPS)         {
 218     MethodCounters* mcs = get_method_counters(CHECK);
 219     if (mcs != NULL) {
 220       mcs->decr_number_of_breakpoints();
 221     }
 222   }
 223   // Initialization only
 224   void clear_number_of_breakpoints()             {
 225     MethodCounters* mcs = method_counters();
 226     if (mcs != NULL) {
 227       mcs->clear_number_of_breakpoints();
 228     }
 229   }
 230 
 231   // index into InstanceKlass methods() array
 232   // note: also used by jfr
 233   u2 method_idnum() const           { return constMethod()->method_idnum(); }
 234   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }
 235 



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