1 /*
   2  * Copyright (c) 1997, 2013, 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 // Memory layout (each line represents a word). Note that most applications load thousands of methods,
  44 // so keeping the size of this structure small has a big impact on footprint.
  45 //
  46 // We put all oops and method_size first for better gc cache locality.
  47 //
  48 // The actual bytecodes are inlined after the end of the Method struct.
  49 //
  50 // There are bits in the access_flags telling whether inlined tables are present.
  51 // Note that accessing the line number and local variable tables is not performance critical at all.
  52 // Accessing the checked exceptions table is used by reflection, so we put that last to make access
  53 // to it fast.
  54 //
  55 // The line number table is compressed and inlined following the byte codes. It is found as the first
  56 // byte following the byte codes. The checked exceptions table and the local variable table are inlined
  57 // after the line number table, and indexed from the end of the method. We do not compress the checked
  58 // exceptions table since the average length is less than 2, and do not bother to compress the local
  59 // variable table either since it is mostly absent.
  60 //
  61 // Note that native_function and signature_handler has to be at fixed offsets (required by the interpreter)
  62 //
  63 // |------------------------------------------------------|
  64 // | header                                               |
  65 // | klass                                                |
  66 // |------------------------------------------------------|
  67 // | ConstMethod*                   (oop)                 |
  68 // |------------------------------------------------------|
  69 // | methodData                     (oop)                 |
  70 // | methodCounters                                       |
  71 // |------------------------------------------------------|
  72 // | access_flags                                         |
  73 // | vtable_index                                         |
  74 // |------------------------------------------------------|
  75 // | result_index (C++ interpreter only)                  |
  76 // |------------------------------------------------------|
  77 // | method_size             |   intrinsic_id|   flags    |
  78 // |------------------------------------------------------|
  79 // | code                           (pointer)             |
  80 // | i2i                            (pointer)             |
  81 // | adapter                        (pointer)             |
  82 // | from_compiled_entry            (pointer)             |
  83 // | from_interpreted_entry         (pointer)             |
  84 // |------------------------------------------------------|
  85 // | native_function       (present only if native)       |
  86 // | signature_handler     (present only if native)       |
  87 // |------------------------------------------------------|
  88 
  89 
  90 class CheckedExceptionElement;
  91 class LocalVariableTableElement;
  92 class AdapterHandlerEntry;
  93 class MethodData;
  94 class MethodCounters;
  95 class ConstMethod;
  96 class InlineTableSizes;
  97 class KlassSizeStats;
  98 
  99 class Method : public Metadata {
 100  friend class VMStructs;
 101  private:
 102   ConstMethod*      _constMethod;                // Method read-only data.
 103   MethodData*       _method_data;
 104   MethodCounters*   _method_counters;
 105   AccessFlags       _access_flags;               // Access flags
 106   int               _vtable_index;               // vtable index of this method (see VtableIndexFlag)
 107                                                  // note: can have vtables with >2**16 elements (because of inheritance)
 108 #ifdef CC_INTERP
 109   int               _result_index;               // C++ interpreter needs for converting results to/from stack
 110 #endif
 111   u2                _method_size;                // size of this object
 112   u1                _intrinsic_id;               // vmSymbols::intrinsic_id (0 == _none)
 113   u1                _jfr_towrite      : 1,       // Flags
 114                     _caller_sensitive : 1,
 115                     _force_inline     : 1,
 116                     _hidden           : 1,
 117                     _dont_inline      : 1,
 118                                       : 3;
 119 
 120 #ifndef PRODUCT
 121   int               _compiled_invocation_count;  // Number of nmethod invocations so far (for perf. debugging)
 122 #endif
 123   // Entry point for calling both from and to the interpreter.
 124   address _i2i_entry;           // All-args-on-stack calling convention
 125   // Adapter blob (i2c/c2i) for this Method*. Set once when method is linked.
 126   AdapterHandlerEntry* _adapter;
 127   // Entry point for calling from compiled code, to compiled code if it exists
 128   // or else the interpreter.
 129   volatile address _from_compiled_entry;        // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
 130   // The entry point for calling both from and to compiled code is
 131   // "_code->entry_point()".  Because of tiered compilation and de-opt, this
 132   // field can come and go.  It can transition from NULL to not-null at any
 133   // time (whenever a compile completes).  It can transition from not-null to
 134   // NULL only at safepoints (because of a de-opt).
 135   nmethod* volatile _code;                       // Points to the corresponding piece of native code
 136   volatile address           _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
 137 
 138   // Constructor
 139   Method(ConstMethod* xconst, AccessFlags access_flags, int size);
 140  public:
 141 
 142   static Method* allocate(ClassLoaderData* loader_data,
 143                           int byte_code_size,
 144                           AccessFlags access_flags,
 145                           InlineTableSizes* sizes,
 146                           ConstMethod::MethodType method_type,
 147                           TRAPS);
 148 
 149   // CDS and vtbl checking can create an empty Method to get vtbl pointer.
 150   Method(){}
 151 
 152   // The Method vtable is restored by this call when the Method is in the
 153   // shared archive.  See patch_klass_vtables() in metaspaceShared.cpp for
 154   // all the gory details.  SA, dtrace and pstack helpers distinguish metadata
 155   // by their vtable.
 156   void restore_vtable() { guarantee(is_method(), "vtable restored by this call"); }
 157   bool is_method() const volatile { return true; }
 158 
 159   void restore_unshareable_info(TRAPS);
 160 
 161   // accessors for instance variables
 162 
 163   ConstMethod* constMethod() const             { return _constMethod; }
 164   void set_constMethod(ConstMethod* xconst)    { _constMethod = xconst; }
 165 
 166 
 167   static address make_adapters(methodHandle mh, TRAPS);
 168   volatile address from_compiled_entry() const   { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }
 169   volatile address from_interpreted_entry() const{ return (address)OrderAccess::load_ptr_acquire(&_from_interpreted_entry); }
 170 
 171   // access flag
 172   AccessFlags access_flags() const               { return _access_flags;  }
 173   void set_access_flags(AccessFlags flags)       { _access_flags = flags; }
 174 
 175   // name
 176   Symbol* name() const                           { return constants()->symbol_at(name_index()); }
 177   int name_index() const                         { return constMethod()->name_index();         }
 178   void set_name_index(int index)                 { constMethod()->set_name_index(index);       }
 179 
 180   // signature
 181   Symbol* signature() const                      { return constants()->symbol_at(signature_index()); }
 182   int signature_index() const                    { return constMethod()->signature_index();         }
 183   void set_signature_index(int index)            { constMethod()->set_signature_index(index);       }
 184 
 185   // generics support
 186   Symbol* generic_signature() const              { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : (Symbol*)NULL); }
 187   int generic_signature_index() const            { return constMethod()->generic_signature_index(); }
 188   void set_generic_signature_index(int index)    { constMethod()->set_generic_signature_index(index); }
 189 
 190   // annotations support
 191   AnnotationArray* annotations() const           {
 192     return constMethod()->method_annotations();
 193   }
 194   AnnotationArray* parameter_annotations() const {
 195     return constMethod()->parameter_annotations();
 196   }
 197   AnnotationArray* annotation_default() const    {
 198     return constMethod()->default_annotations();
 199   }
 200   AnnotationArray* type_annotations() const      {
 201     return constMethod()->type_annotations();
 202   }
 203 
 204 #ifdef CC_INTERP
 205   void set_result_index(BasicType type);
 206   int  result_index()                            { return _result_index; }
 207 #endif
 208 
 209   // Helper routine: get klass name + "." + method name + signature as
 210   // C string, for the purpose of providing more useful NoSuchMethodErrors
 211   // and fatal error handling. The string is allocated in resource
 212   // area if a buffer is not provided by the caller.
 213   char* name_and_sig_as_C_string() const;
 214   char* name_and_sig_as_C_string(char* buf, int size) const;
 215 
 216   // Static routine in the situations we don't have a Method*
 217   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
 218   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
 219 
 220   Bytecodes::Code java_code_at(int bci) const {
 221     return Bytecodes::java_code_at(this, bcp_from(bci));
 222   }
 223   Bytecodes::Code code_at(int bci) const {
 224     return Bytecodes::code_at(this, bcp_from(bci));
 225   }
 226 
 227   // JVMTI breakpoints
 228   Bytecodes::Code orig_bytecode_at(int bci) const;
 229   void        set_orig_bytecode_at(int bci, Bytecodes::Code code);
 230   void set_breakpoint(int bci);
 231   void clear_breakpoint(int bci);
 232   void clear_all_breakpoints();
 233   // Tracking number of breakpoints, for fullspeed debugging.
 234   // Only mutated by VM thread.
 235   u2   number_of_breakpoints()             const {
 236     MethodCounters* mcs = method_counters();
 237     if (mcs == NULL) {
 238       return 0;
 239     } else {
 240       return mcs->number_of_breakpoints();
 241     }
 242   }
 243   void incr_number_of_breakpoints(TRAPS)         {
 244     MethodCounters* mcs = get_method_counters(CHECK);
 245     if (mcs != NULL) {
 246       mcs->incr_number_of_breakpoints();
 247     }
 248   }
 249   void decr_number_of_breakpoints(TRAPS)         {
 250     MethodCounters* mcs = get_method_counters(CHECK);
 251     if (mcs != NULL) {
 252       mcs->decr_number_of_breakpoints();
 253     }
 254   }
 255   // Initialization only
 256   void clear_number_of_breakpoints()             {
 257     MethodCounters* mcs = method_counters();
 258     if (mcs != NULL) {
 259       mcs->clear_number_of_breakpoints();
 260     }
 261   }
 262 
 263   // index into InstanceKlass methods() array
 264   // note: also used by jfr
 265   u2 method_idnum() const           { return constMethod()->method_idnum(); }
 266   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }
 267 
 268   // code size
 269   int code_size() const                  { return constMethod()->code_size(); }
 270 
 271   // method size
 272   int method_size() const                        { return _method_size; }
 273   void set_method_size(int size) {
 274     assert(0 <= size && size < (1 << 16), "invalid method size");
 275     _method_size = size;
 276   }
 277 
 278   // constant pool for Klass* holding this method
 279   ConstantPool* constants() const              { return constMethod()->constants(); }
 280   void set_constants(ConstantPool* c)          { constMethod()->set_constants(c); }
 281 
 282   // max stack
 283   // return original max stack size for method verification
 284   int  verifier_max_stack() const                { return constMethod()->max_stack(); }
 285   int           max_stack() const                { return constMethod()->max_stack() + extra_stack_entries(); }
 286   void      set_max_stack(int size)              {        constMethod()->set_max_stack(size); }
 287 
 288   // max locals
 289   int  max_locals() const                        { return constMethod()->max_locals(); }
 290   void set_max_locals(int size)                  { constMethod()->set_max_locals(size); }
 291 
 292   int highest_comp_level() const;
 293   void set_highest_comp_level(int level);
 294   int highest_osr_comp_level() const;
 295   void set_highest_osr_comp_level(int level);
 296 
 297   // Count of times method was exited via exception while interpreting
 298   void interpreter_throwout_increment(TRAPS) {
 299     MethodCounters* mcs = get_method_counters(CHECK);
 300     if (mcs != NULL) {
 301       mcs->interpreter_throwout_increment();
 302     }
 303   }
 304 
 305   int  interpreter_throwout_count() const        {
 306     MethodCounters* mcs = method_counters();
 307     if (mcs == NULL) {
 308       return 0;
 309     } else {
 310       return mcs->interpreter_throwout_count();
 311     }
 312   }
 313 
 314   // size of parameters
 315   int  size_of_parameters() const                { return constMethod()->size_of_parameters(); }
 316   void set_size_of_parameters(int size)          { constMethod()->set_size_of_parameters(size); }
 317 
 318   bool has_stackmap_table() const {
 319     return constMethod()->has_stackmap_table();
 320   }
 321 
 322   Array<u1>* stackmap_data() const {
 323     return constMethod()->stackmap_data();
 324   }
 325 
 326   void set_stackmap_data(Array<u1>* sd) {
 327     constMethod()->set_stackmap_data(sd);
 328   }
 329 
 330   // exception handler table
 331   bool has_exception_handler() const
 332                              { return constMethod()->has_exception_handler(); }
 333   int exception_table_length() const
 334                              { return constMethod()->exception_table_length(); }
 335   ExceptionTableElement* exception_table_start() const
 336                              { return constMethod()->exception_table_start(); }
 337 
 338   // Finds the first entry point bci of an exception handler for an
 339   // exception of klass ex_klass thrown at throw_bci. A value of NULL
 340   // for ex_klass indicates that the exception klass is not known; in
 341   // this case it matches any constraint class. Returns -1 if the
 342   // exception cannot be handled in this method. The handler
 343   // constraint classes are loaded if necessary. Note that this may
 344   // throw an exception if loading of the constraint classes causes
 345   // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
 346   // If an exception is thrown, returns the bci of the
 347   // exception handler which caused the exception to be thrown, which
 348   // is needed for proper retries. See, for example,
 349   // InterpreterRuntime::exception_handler_for_exception.
 350   static int fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS);
 351 
 352   // method data access
 353   MethodData* method_data() const              {
 354     return _method_data;
 355   }
 356 
 357   void set_method_data(MethodData* data)       {
 358     // The store into method must be released. On platforms without
 359     // total store order (TSO) the reference may become visible before
 360     // the initialization of data otherwise.
 361     OrderAccess::release_store_ptr((volatile void *)&_method_data, data);
 362   }
 363 
 364   MethodCounters* method_counters() const {
 365     return _method_counters;
 366   }
 367 
 368   void clear_method_counters() {
 369     _method_counters = NULL;
 370   }
 371 
 372   bool init_method_counters(MethodCounters* counters) {
 373     // Try to install a pointer to MethodCounters, return true on success.
 374     return Atomic::cmpxchg_ptr(counters, (volatile void*)&_method_counters, NULL) == NULL;
 375   }
 376 
 377 #ifdef TIERED
 378   // We are reusing interpreter_invocation_count as a holder for the previous event count!
 379   // We can do that since interpreter_invocation_count is not used in tiered.
 380   int prev_event_count() const                   {
 381     if (method_counters() == NULL) {
 382       return 0;
 383     } else {
 384       return method_counters()->interpreter_invocation_count();
 385     }
 386   }
 387   void set_prev_event_count(int count) {
 388     MethodCounters* mcs = method_counters();
 389     if (mcs != NULL) {
 390       mcs->set_interpreter_invocation_count(count);
 391     }
 392   }
 393   jlong prev_time() const                        {
 394     MethodCounters* mcs = method_counters();
 395     return mcs == NULL ? 0 : mcs->prev_time();
 396   }
 397   void set_prev_time(jlong time) {
 398     MethodCounters* mcs = method_counters();
 399     if (mcs != NULL) {
 400       mcs->set_prev_time(time);
 401     }
 402   }
 403   float rate() const                             {
 404     MethodCounters* mcs = method_counters();
 405     return mcs == NULL ? 0 : mcs->rate();
 406   }
 407   void set_rate(float rate) {
 408     MethodCounters* mcs = method_counters();
 409     if (mcs != NULL) {
 410       mcs->set_rate(rate);
 411     }
 412   }
 413 #endif
 414 
 415   int invocation_count();
 416   int backedge_count();
 417 
 418   bool was_executed_more_than(int n);
 419   bool was_never_executed()                      { return !was_executed_more_than(0); }
 420 
 421   static void build_interpreter_method_data(methodHandle method, TRAPS);
 422 
 423   static MethodCounters* build_method_counters(Method* m, TRAPS);
 424 
 425   int interpreter_invocation_count() {
 426     if (TieredCompilation) {
 427       return invocation_count();
 428     } else {
 429       MethodCounters* mcs = method_counters();
 430       return (mcs == NULL) ? 0 : mcs->interpreter_invocation_count();
 431     }
 432   }
 433   int increment_interpreter_invocation_count(TRAPS) {
 434     if (TieredCompilation) ShouldNotReachHere();
 435     MethodCounters* mcs = get_method_counters(CHECK_0);
 436     return (mcs == NULL) ? 0 : mcs->increment_interpreter_invocation_count();
 437   }
 438 
 439 #ifndef PRODUCT
 440   int  compiled_invocation_count() const         { return _compiled_invocation_count;  }
 441   void set_compiled_invocation_count(int count)  { _compiled_invocation_count = count; }
 442 #endif // not PRODUCT
 443 
 444   // Clear (non-shared space) pointers which could not be relevant
 445   // if this (shared) method were mapped into another JVM.
 446   void remove_unshareable_info();
 447 
 448   // nmethod/verified compiler entry
 449   address verified_code_entry();
 450   bool check_code() const;      // Not inline to avoid circular ref
 451   nmethod* volatile code() const                 { assert( check_code(), "" ); return (nmethod *)OrderAccess::load_ptr_acquire(&_code); }
 452   void clear_code();            // Clear out any compiled code
 453   static void set_code(methodHandle mh, nmethod* code);
 454   void set_adapter_entry(AdapterHandlerEntry* adapter) {  _adapter = adapter; }
 455   address get_i2c_entry();
 456   address get_c2i_entry();
 457   address get_c2i_unverified_entry();
 458   AdapterHandlerEntry* adapter() {  return _adapter; }
 459   // setup entry points
 460   void link_method(methodHandle method, TRAPS);
 461   // clear entry points. Used by sharing code
 462   void unlink_method();
 463 
 464   // vtable index
 465   enum VtableIndexFlag {
 466     // Valid vtable indexes are non-negative (>= 0).
 467     // These few negative values are used as sentinels.
 468     itable_index_max        = -10, // first itable index, growing downward
 469     pending_itable_index    = -9,  // itable index will be assigned
 470     invalid_vtable_index    = -4,  // distinct from any valid vtable index
 471     garbage_vtable_index    = -3,  // not yet linked; no vtable layout yet
 472     nonvirtual_vtable_index = -2   // there is no need for vtable dispatch
 473     // 6330203 Note:  Do not use -1, which was overloaded with many meanings.
 474   };
 475   DEBUG_ONLY(bool valid_vtable_index() const     { return _vtable_index >= nonvirtual_vtable_index; })
 476   bool has_vtable_index() const                  { return _vtable_index >= 0; }
 477   int  vtable_index() const                      { return _vtable_index; }
 478   void set_vtable_index(int index)               { _vtable_index = index; }
 479   DEBUG_ONLY(bool valid_itable_index() const     { return _vtable_index <= pending_itable_index; })
 480   bool has_itable_index() const                  { return _vtable_index <= itable_index_max; }
 481   int  itable_index() const                      { assert(valid_itable_index(), "");
 482                                                    return itable_index_max - _vtable_index; }
 483   void set_itable_index(int index)               { _vtable_index = itable_index_max - index; assert(valid_itable_index(), ""); }
 484 
 485   // interpreter entry
 486   address interpreter_entry() const              { return _i2i_entry; }
 487   // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
 488   void set_interpreter_entry(address entry)      { _i2i_entry = entry;  _from_interpreted_entry = entry; }
 489 
 490   // native function (used for native methods only)
 491   enum {
 492     native_bind_event_is_interesting = true
 493   };
 494   address native_function() const                { return *(native_function_addr()); }
 495   address critical_native_function();
 496 
 497   // Must specify a real function (not NULL).
 498   // Use clear_native_function() to unregister.
 499   void set_native_function(address function, bool post_event_flag);
 500   bool has_native_function() const;
 501   void clear_native_function();
 502 
 503   // signature handler (used for native methods only)
 504   address signature_handler() const              { return *(signature_handler_addr()); }
 505   void set_signature_handler(address handler);
 506 
 507   // Interpreter oopmap support
 508   void mask_for(int bci, InterpreterOopMap* mask);
 509 
 510 #ifndef PRODUCT
 511   // operations on invocation counter
 512   void print_invocation_count();
 513 #endif
 514 
 515   // byte codes
 516   void    set_code(address code)      { return constMethod()->set_code(code); }
 517   address code_base() const           { return constMethod()->code_base(); }
 518   bool    contains(address bcp) const { return constMethod()->contains(bcp); }
 519 
 520   // prints byte codes
 521   void print_codes() const            { print_codes_on(tty); }
 522   void print_codes_on(outputStream* st) const                      PRODUCT_RETURN;
 523   void print_codes_on(int from, int to, outputStream* st) const    PRODUCT_RETURN;
 524 
 525   // method parameters
 526   bool has_method_parameters() const
 527                          { return constMethod()->has_method_parameters(); }
 528   int method_parameters_length() const
 529                          { return constMethod()->method_parameters_length(); }
 530   MethodParametersElement* method_parameters_start() const
 531                           { return constMethod()->method_parameters_start(); }
 532 
 533   // checked exceptions
 534   int checked_exceptions_length() const
 535                          { return constMethod()->checked_exceptions_length(); }
 536   CheckedExceptionElement* checked_exceptions_start() const
 537                           { return constMethod()->checked_exceptions_start(); }
 538 
 539   // localvariable table
 540   bool has_localvariable_table() const
 541                           { return constMethod()->has_localvariable_table(); }
 542   int localvariable_table_length() const
 543                         { return constMethod()->localvariable_table_length(); }
 544   LocalVariableTableElement* localvariable_table_start() const
 545                          { return constMethod()->localvariable_table_start(); }
 546 
 547   bool has_linenumber_table() const
 548                               { return constMethod()->has_linenumber_table(); }
 549   u_char* compressed_linenumber_table() const
 550                        { return constMethod()->compressed_linenumber_table(); }
 551 
 552   // method holder (the Klass* holding this method)
 553   InstanceKlass* method_holder() const         { return constants()->pool_holder(); }
 554 
 555   void compute_size_of_parameters(Thread *thread); // word size of parameters (receiver if any + arguments)
 556   Symbol* klass_name() const;                    // returns the name of the method holder
 557   BasicType result_type() const;                 // type of the method result
 558   int result_type_index() const;                 // type index 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 an initializer (<init> or <clinit>).
 623   bool is_initializer() const;
 624 
 625   // returns true if the method is static OR if the classfile version < 51
 626   bool has_valid_initializer_flags() const;
 627 
 628   // returns true if the method name is <clinit> and the method has
 629   // valid static initializer flags.
 630   bool is_static_initializer() const;
 631 
 632   // compiled code support
 633   // NOTE: code() is inherently racy as deopt can be clearing code
 634   // simultaneously. Use with caution.
 635   bool has_compiled_code() const                 { return code() != NULL; }
 636 
 637   // sizing
 638   static int header_size()                       { return sizeof(Method)/HeapWordSize; }
 639   static int size(bool is_native);
 640   int size() const                               { return method_size(); }
 641 #if INCLUDE_SERVICES
 642   void collect_statistics(KlassSizeStats *sz) const;
 643 #endif
 644 
 645   // interpreter support
 646   static ByteSize const_offset()                 { return byte_offset_of(Method, _constMethod       ); }
 647   static ByteSize access_flags_offset()          { return byte_offset_of(Method, _access_flags      ); }
 648 #ifdef CC_INTERP
 649   static ByteSize result_index_offset()          { return byte_offset_of(Method, _result_index ); }
 650 #endif /* CC_INTERP */
 651   static ByteSize from_compiled_offset()         { return byte_offset_of(Method, _from_compiled_entry); }
 652   static ByteSize code_offset()                  { return byte_offset_of(Method, _code); }
 653   static ByteSize method_data_offset()           {
 654     return byte_offset_of(Method, _method_data);
 655   }
 656   static ByteSize method_counters_offset()       {
 657     return byte_offset_of(Method, _method_counters);
 658   }
 659 #ifndef PRODUCT
 660   static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
 661 #endif // not PRODUCT
 662   static ByteSize native_function_offset()       { return in_ByteSize(sizeof(Method));                 }
 663   static ByteSize from_interpreted_offset()      { return byte_offset_of(Method, _from_interpreted_entry ); }
 664   static ByteSize interpreter_entry_offset()     { return byte_offset_of(Method, _i2i_entry ); }
 665   static ByteSize signature_handler_offset()     { return in_ByteSize(sizeof(Method) + wordSize);      }
 666 
 667   // for code generation
 668   static int method_data_offset_in_bytes()       { return offset_of(Method, _method_data); }
 669   static int intrinsic_id_offset_in_bytes()      { return offset_of(Method, _intrinsic_id); }
 670   static int intrinsic_id_size_in_bytes()        { return sizeof(u1); }
 671 
 672   // Static methods that are used to implement member methods where an exposed this pointer
 673   // is needed due to possible GCs
 674   static objArrayHandle resolved_checked_exceptions_impl(Method* this_oop, TRAPS);
 675 
 676   // Returns the byte code index from the byte code pointer
 677   int     bci_from(address bcp) const;
 678   address bcp_from(int     bci) const;
 679   int validate_bci_from_bcx(intptr_t bcx) const;
 680 
 681   // Returns the line number for a bci if debugging information for the method is prowided,
 682   // -1 is returned otherwise.
 683   int line_number_from_bci(int bci) const;
 684 
 685   // Reflection support
 686   bool is_overridden_in(Klass* k) const;
 687 
 688   // Stack walking support
 689   bool is_ignored_by_security_stack_walk() const;
 690 
 691   // JSR 292 support
 692   bool is_method_handle_intrinsic() const;          // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
 693   bool is_compiled_lambda_form() const;             // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
 694   bool has_member_arg() const;                      // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
 695   static methodHandle make_method_handle_intrinsic(vmIntrinsics::ID iid, // _invokeBasic, _linkToVirtual
 696                                                    Symbol* signature, //anything at all
 697                                                    TRAPS);
 698   static Klass* check_non_bcp_klass(Klass* klass);
 699 
 700   // How many extra stack entries for invokedynamic when it's enabled
 701   static const int extra_stack_entries_for_jsr292 = 1;
 702 
 703   // this operates only on invoke methods:
 704   // presize interpreter frames for extra interpreter stack entries, if needed
 705   // Account for the extra appendix argument for invokehandle/invokedynamic
 706   static int extra_stack_entries() { return EnableInvokeDynamic ? extra_stack_entries_for_jsr292 : 0; }
 707   static int extra_stack_words();  // = extra_stack_entries() * Interpreter::stackElementSize
 708 
 709   // RedefineClasses() support:
 710   bool is_old() const                               { return access_flags().is_old(); }
 711   void set_is_old()                                 { _access_flags.set_is_old(); }
 712   bool is_obsolete() const                          { return access_flags().is_obsolete(); }
 713   void set_is_obsolete()                            { _access_flags.set_is_obsolete(); }
 714   bool on_stack() const                             { return access_flags().on_stack(); }
 715   void set_on_stack(const bool value);
 716 
 717   // see the definition in Method*.cpp for the gory details
 718   bool should_not_be_cached() const;
 719 
 720   // JVMTI Native method prefixing support:
 721   bool is_prefixed_native() const                   { return access_flags().is_prefixed_native(); }
 722   void set_is_prefixed_native()                     { _access_flags.set_is_prefixed_native(); }
 723 
 724   // Rewriting support
 725   static methodHandle clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
 726                                           u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
 727 
 728   // jmethodID handling
 729   // Because the useful life-span of a jmethodID cannot be determined,
 730   // once created they are never reclaimed.  The methods to which they refer,
 731   // however, can be GC'ed away if the class is unloaded or if the method is
 732   // made obsolete or deleted -- in these cases, the jmethodID
 733   // refers to NULL (as is the case for any weak reference).
 734   static jmethodID make_jmethod_id(ClassLoaderData* loader_data, Method* mh);
 735   static void destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID mid);
 736 
 737   // Use resolve_jmethod_id() in situations where the caller is expected
 738   // to provide a valid jmethodID; the only sanity checks are in asserts;
 739   // result guaranteed not to be NULL.
 740   inline static Method* resolve_jmethod_id(jmethodID mid) {
 741     assert(mid != NULL, "JNI method id should not be null");
 742     return *((Method**)mid);
 743   }
 744 
 745   // Use checked_resolve_jmethod_id() in situations where the caller
 746   // should provide a valid jmethodID, but might not. NULL is returned
 747   // when the jmethodID does not refer to a valid method.
 748   static Method* checked_resolve_jmethod_id(jmethodID mid);
 749 
 750   static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
 751   static bool is_method_id(jmethodID mid);
 752 
 753   // Clear methods
 754   static void clear_jmethod_ids(ClassLoaderData* loader_data);
 755   static void print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
 756 
 757   // Get this method's jmethodID -- allocate if it doesn't exist
 758   jmethodID jmethod_id()                            { methodHandle this_h(this);
 759                                                       return InstanceKlass::get_jmethod_id(method_holder(), this_h); }
 760 
 761   // Lookup the jmethodID for this method.  Return NULL if not found.
 762   // NOTE that this function can be called from a signal handler
 763   // (see AsyncGetCallTrace support for Forte Analyzer) and this
 764   // needs to be async-safe. No allocation should be done and
 765   // so handles are not used to avoid deadlock.
 766   jmethodID find_jmethod_id_or_null()               { return method_holder()->jmethod_id_or_null(this); }
 767 
 768   // Support for inlining of intrinsic methods
 769   vmIntrinsics::ID intrinsic_id() const          { return (vmIntrinsics::ID) _intrinsic_id;           }
 770   void     set_intrinsic_id(vmIntrinsics::ID id) {                           _intrinsic_id = (u1) id; }
 771 
 772   // Helper routines for intrinsic_id() and vmIntrinsics::method().
 773   void init_intrinsic_id();     // updates from _none if a match
 774   static vmSymbols::SID klass_id_for_intrinsics(Klass* holder);
 775 
 776   bool     jfr_towrite()            { return _jfr_towrite;          }
 777   void set_jfr_towrite(bool x)      {        _jfr_towrite = x;      }
 778   bool     caller_sensitive()       { return _caller_sensitive;     }
 779   void set_caller_sensitive(bool x) {        _caller_sensitive = x; }
 780   bool     force_inline()           { return _force_inline;         }
 781   void set_force_inline(bool x)     {        _force_inline = x;     }
 782   bool     dont_inline()            { return _dont_inline;          }
 783   void set_dont_inline(bool x)      {        _dont_inline = x;      }
 784   bool  is_hidden()                 { return _hidden;               }
 785   void set_hidden(bool x)           {        _hidden = x;           }
 786   ConstMethod::MethodType method_type() const {
 787       return _constMethod->method_type();
 788   }
 789   bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
 790 
 791   // On-stack replacement support
 792   bool has_osr_nmethod(int level, bool match_level) {
 793    return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != NULL;
 794   }
 795 
 796   nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
 797     return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
 798   }
 799 
 800   // Inline cache support
 801   void cleanup_inline_caches();
 802 
 803   // Find if klass for method is loaded
 804   bool is_klass_loaded_by_klass_index(int klass_index) const;
 805   bool is_klass_loaded(int refinfo_index, bool must_be_resolved = false) const;
 806 
 807   // Indicates whether compilation failed earlier for this method, or
 808   // whether it is not compilable for another reason like having a
 809   // breakpoint set in it.
 810   bool  is_not_compilable(int comp_level = CompLevel_any) const;
 811   void set_not_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 812   void set_not_compilable_quietly(int comp_level = CompLevel_all) {
 813     set_not_compilable(comp_level, false);
 814   }
 815   bool  is_not_osr_compilable(int comp_level = CompLevel_any) const;
 816   void set_not_osr_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 817   void set_not_osr_compilable_quietly(int comp_level = CompLevel_all) {
 818     set_not_osr_compilable(comp_level, false);
 819   }
 820   bool is_always_compilable() const;
 821 
 822  private:
 823   void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
 824 
 825  public:
 826   MethodCounters* get_method_counters(TRAPS) {
 827     if (_method_counters == NULL) {
 828       build_method_counters(this, CHECK_AND_CLEAR_NULL);
 829     }
 830     return _method_counters;
 831   }
 832 
 833   bool   is_not_c1_compilable() const         { return access_flags().is_not_c1_compilable();  }
 834   void  set_not_c1_compilable()               {       _access_flags.set_not_c1_compilable();   }
 835   void clear_not_c1_compilable()              {       _access_flags.clear_not_c1_compilable(); }
 836   bool   is_not_c2_compilable() const         { return access_flags().is_not_c2_compilable();  }
 837   void  set_not_c2_compilable()               {       _access_flags.set_not_c2_compilable();   }
 838   void clear_not_c2_compilable()              {       _access_flags.clear_not_c2_compilable(); }
 839 
 840   bool    is_not_c1_osr_compilable() const    { return is_not_c1_compilable(); }  // don't waste an accessFlags bit
 841   void   set_not_c1_osr_compilable()          {       set_not_c1_compilable(); }  // don't waste an accessFlags bit
 842   void clear_not_c1_osr_compilable()          {     clear_not_c1_compilable(); }  // don't waste an accessFlags bit
 843   bool   is_not_c2_osr_compilable() const     { return access_flags().is_not_c2_osr_compilable();  }
 844   void  set_not_c2_osr_compilable()           {       _access_flags.set_not_c2_osr_compilable();   }
 845   void clear_not_c2_osr_compilable()          {       _access_flags.clear_not_c2_osr_compilable(); }
 846 
 847   // Background compilation support
 848   bool queued_for_compilation() const  { return access_flags().queued_for_compilation(); }
 849   void set_queued_for_compilation()    { _access_flags.set_queued_for_compilation();     }
 850   void clear_queued_for_compilation()  { _access_flags.clear_queued_for_compilation();   }
 851 
 852   // Resolve all classes in signature, return 'true' if successful
 853   static bool load_signature_classes(methodHandle m, TRAPS);
 854 
 855   // Return if true if not all classes references in signature, including return type, has been loaded
 856   static bool has_unloaded_classes_in_signature(methodHandle m, TRAPS);
 857 
 858   // Printing
 859   void print_short_name(outputStream* st = tty); // prints as klassname::methodname; Exposed so field engineers can debug VM
 860 #if INCLUDE_JVMTI
 861   void print_name(outputStream* st = tty); // prints as "virtual void foo(int)"; exposed for TraceRedefineClasses
 862 #else
 863   void print_name(outputStream* st = tty)        PRODUCT_RETURN; // prints as "virtual void foo(int)"
 864 #endif
 865 
 866   // Helper routine used for method sorting
 867   static void sort_methods(Array<Method*>* methods, bool idempotent = false, bool set_idnums = true);
 868 
 869   // Deallocation function for redefine classes or if an error occurs
 870   void deallocate_contents(ClassLoaderData* loader_data);
 871 
 872   // Printing
 873 #ifndef PRODUCT
 874   void print_on(outputStream* st) const;
 875 #endif
 876   void print_value_on(outputStream* st) const;
 877 
 878   const char* internal_name() const { return "{method}"; }
 879 
 880   // Check for valid method pointer
 881   static bool has_method_vptr(const void* ptr);
 882   bool is_valid_method() const;
 883 
 884   // Verify
 885   void verify() { verify_on(tty); }
 886   void verify_on(outputStream* st);
 887 
 888  private:
 889 
 890   // Inlined elements
 891   address* native_function_addr() const          { assert(is_native(), "must be native"); return (address*) (this+1); }
 892   address* signature_handler_addr() const        { return native_function_addr() + 1; }
 893 };
 894 
 895 
 896 // Utility class for compressing line number tables
 897 
 898 class CompressedLineNumberWriteStream: public CompressedWriteStream {
 899  private:
 900   int _bci;
 901   int _line;
 902  public:
 903   // Constructor
 904   CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
 905   CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
 906 
 907   // Write (bci, line number) pair to stream
 908   void write_pair_regular(int bci_delta, int line_delta);
 909 
 910   inline void write_pair_inline(int bci, int line) {
 911     int bci_delta = bci - _bci;
 912     int line_delta = line - _line;
 913     _bci = bci;
 914     _line = line;
 915     // Skip (0,0) deltas - they do not add information and conflict with terminator.
 916     if (bci_delta == 0 && line_delta == 0) return;
 917     // Check if bci is 5-bit and line number 3-bit unsigned.
 918     if (((bci_delta & ~0x1F) == 0) && ((line_delta & ~0x7) == 0)) {
 919       // Compress into single byte.
 920       jubyte value = ((jubyte) bci_delta << 3) | (jubyte) line_delta;
 921       // Check that value doesn't match escape character.
 922       if (value != 0xFF) {
 923         write_byte(value);
 924         return;
 925       }
 926     }
 927     write_pair_regular(bci_delta, line_delta);
 928   }
 929 
 930 // Windows AMD64 + Apr 2005 PSDK with /O2 generates bad code for write_pair.
 931 // Disabling optimization doesn't work for methods in header files
 932 // so we force it to call through the non-optimized version in the .cpp.
 933 // It's gross, but it's the only way we can ensure that all callers are
 934 // fixed.  _MSC_VER is defined by the windows compiler
 935 #if defined(_M_AMD64) && _MSC_VER >= 1400
 936   void write_pair(int bci, int line);
 937 #else
 938   void write_pair(int bci, int line) { write_pair_inline(bci, line); }
 939 #endif
 940 
 941   // Write end-of-stream marker
 942   void write_terminator()                        { write_byte(0); }
 943 };
 944 
 945 
 946 // Utility class for decompressing line number tables
 947 
 948 class CompressedLineNumberReadStream: public CompressedReadStream {
 949  private:
 950   int _bci;
 951   int _line;
 952  public:
 953   // Constructor
 954   CompressedLineNumberReadStream(u_char* buffer);
 955   // Read (bci, line number) pair from stream. Returns false at end-of-stream.
 956   bool read_pair();
 957   // Accessing bci and line number (after calling read_pair)
 958   int bci() const                               { return _bci; }
 959   int line() const                              { return _line; }
 960 };
 961 
 962 
 963 /// Fast Breakpoints.
 964 
 965 // If this structure gets more complicated (because bpts get numerous),
 966 // move it into its own header.
 967 
 968 // There is presently no provision for concurrent access
 969 // to breakpoint lists, which is only OK for JVMTI because
 970 // breakpoints are written only at safepoints, and are read
 971 // concurrently only outside of safepoints.
 972 
 973 class BreakpointInfo : public CHeapObj<mtClass> {
 974   friend class VMStructs;
 975  private:
 976   Bytecodes::Code  _orig_bytecode;
 977   int              _bci;
 978   u2               _name_index;       // of method
 979   u2               _signature_index;  // of method
 980   BreakpointInfo*  _next;             // simple storage allocation
 981 
 982  public:
 983   BreakpointInfo(Method* m, int bci);
 984 
 985   // accessors
 986   Bytecodes::Code orig_bytecode()                     { return _orig_bytecode; }
 987   void        set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
 988   int         bci()                                   { return _bci; }
 989 
 990   BreakpointInfo*          next() const               { return _next; }
 991   void                 set_next(BreakpointInfo* n)    { _next = n; }
 992 
 993   // helps for searchers
 994   bool match(const Method* m, int bci) {
 995     return bci == _bci && match(m);
 996   }
 997 
 998   bool match(const Method* m) {
 999     return _name_index == m->name_index() &&
1000       _signature_index == m->signature_index();
1001   }
1002 
1003   void set(Method* method);
1004   void clear(Method* method);
1005 };
1006 
1007 // Utility class for access exception handlers
1008 class ExceptionTable : public StackObj {
1009  private:
1010   ExceptionTableElement* _table;
1011   u2  _length;
1012 
1013  public:
1014   ExceptionTable(const Method* m) {
1015     if (m->has_exception_handler()) {
1016       _table = m->exception_table_start();
1017       _length = m->exception_table_length();
1018     } else {
1019       _table = NULL;
1020       _length = 0;
1021     }
1022   }
1023 
1024   int length() const {
1025     return _length;
1026   }
1027 
1028   u2 start_pc(int idx) const {
1029     assert(idx < _length, "out of bounds");
1030     return _table[idx].start_pc;
1031   }
1032 
1033   void set_start_pc(int idx, u2 value) {
1034     assert(idx < _length, "out of bounds");
1035     _table[idx].start_pc = value;
1036   }
1037 
1038   u2 end_pc(int idx) const {
1039     assert(idx < _length, "out of bounds");
1040     return _table[idx].end_pc;
1041   }
1042 
1043   void set_end_pc(int idx, u2 value) {
1044     assert(idx < _length, "out of bounds");
1045     _table[idx].end_pc = value;
1046   }
1047 
1048   u2 handler_pc(int idx) const {
1049     assert(idx < _length, "out of bounds");
1050     return _table[idx].handler_pc;
1051   }
1052 
1053   void set_handler_pc(int idx, u2 value) {
1054     assert(idx < _length, "out of bounds");
1055     _table[idx].handler_pc = value;
1056   }
1057 
1058   u2 catch_type_index(int idx) const {
1059     assert(idx < _length, "out of bounds");
1060     return _table[idx].catch_type_index;
1061   }
1062 
1063   void set_catch_type_index(int idx, u2 value) {
1064     assert(idx < _length, "out of bounds");
1065     _table[idx].catch_type_index = value;
1066   }
1067 };
1068 
1069 #endif // SHARE_VM_OOPS_METHODOOP_HPP