1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_OOPS_METHODOOP_HPP
  26 #define SHARE_VM_OOPS_METHODOOP_HPP
  27 
  28 #include "classfile/vmSymbols.hpp"
  29 #include "code/compressedStream.hpp"
  30 #include "compiler/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 class CheckedExceptionElement;
  90 class LocalVariableTableElement;
  91 class AdapterHandlerEntry;
  92 class MethodData;
  93 class MethodCounters;
  94 class ConstMethod;
  95 class InlineTableSizes;
  96 class KlassSizeStats;
  97 
  98 class Method : public Metadata {
  99  friend class VMStructs;
 100  private:
 101   ConstMethod*      _constMethod;                // Method read-only data.
 102   MethodData*       _method_data;
 103   MethodCounters*   _method_counters;
 104   AccessFlags       _access_flags;               // Access flags
 105   int               _vtable_index;               // vtable index of this method (see VtableIndexFlag)
 106                                                  // note: can have vtables with >2**16 elements (because of inheritance)
 107   u2                _method_size;                // size of this object
 108   u1                _intrinsic_id;               // vmSymbols::intrinsic_id (0 == _none)
 109   u1                _jfr_towrite          : 1,   // Flags
 110                     _caller_sensitive     : 1,
 111                     _force_inline         : 1,
 112                     _hidden               : 1,
 113                     _running_emcp         : 1,
 114                     _dont_inline          : 1,
 115                     _has_injected_profile : 1,
 116                                           : 2;
 117 
 118 #ifndef PRODUCT
 119   int               _compiled_invocation_count;  // Number of nmethod invocations so far (for perf. debugging)
 120 #endif
 121   // Entry point for calling both from and to the interpreter.
 122   address _i2i_entry;           // All-args-on-stack calling convention
 123   // Adapter blob (i2c/c2i) for this Method*. Set once when method is linked.
 124   AdapterHandlerEntry* _adapter;
 125   // Entry point for calling from compiled code, to compiled code if it exists
 126   // or else the interpreter.
 127   volatile address _from_compiled_entry;        // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
 128   // The entry point for calling both from and to compiled code is
 129   // "_code->entry_point()".  Because of tiered compilation and de-opt, this
 130   // field can come and go.  It can transition from NULL to not-null at any
 131   // time (whenever a compile completes).  It can transition from not-null to
 132   // NULL only at safepoints (because of a de-opt).
 133   nmethod* volatile _code;                       // Points to the corresponding piece of native code
 134   volatile address           _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
 135 
 136   // Constructor
 137   Method(ConstMethod* xconst, AccessFlags access_flags, int size);
 138  public:
 139 
 140   static Method* allocate(ClassLoaderData* loader_data,
 141                           int byte_code_size,
 142                           AccessFlags access_flags,
 143                           InlineTableSizes* sizes,
 144                           ConstMethod::MethodType method_type,
 145                           TRAPS);
 146 
 147   // CDS and vtbl checking can create an empty Method to get vtbl pointer.
 148   Method(){}
 149 
 150   // The Method vtable is restored by this call when the Method is in the
 151   // shared archive.  See patch_klass_vtables() in metaspaceShared.cpp for
 152   // all the gory details.  SA, dtrace and pstack helpers distinguish metadata
 153   // by their vtable.
 154   void restore_vtable() { guarantee(is_method(), "vtable restored by this call"); }
 155   bool is_method() const volatile { return true; }
 156 
 157   void restore_unshareable_info(TRAPS);
 158 
 159   // accessors for instance variables
 160 
 161   ConstMethod* constMethod() const             { return _constMethod; }
 162   void set_constMethod(ConstMethod* xconst)    { _constMethod = xconst; }
 163 
 164 
 165   static address make_adapters(methodHandle mh, TRAPS);
 166   volatile address from_compiled_entry() const   { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }
 167   volatile address from_interpreted_entry() const{ return (address)OrderAccess::load_ptr_acquire(&_from_interpreted_entry); }
 168 
 169   // access flag
 170   AccessFlags access_flags() const               { return _access_flags;  }
 171   void set_access_flags(AccessFlags flags)       { _access_flags = flags; }
 172 
 173   // name
 174   Symbol* name() const                           { return constants()->symbol_at(name_index()); }
 175   int name_index() const                         { return constMethod()->name_index();         }
 176   void set_name_index(int index)                 { constMethod()->set_name_index(index);       }
 177 
 178   // signature
 179   Symbol* signature() const                      { return constants()->symbol_at(signature_index()); }
 180   int signature_index() const                    { return constMethod()->signature_index();         }
 181   void set_signature_index(int index)            { constMethod()->set_signature_index(index);       }
 182 
 183   // generics support
 184   Symbol* generic_signature() const              { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : (Symbol*)NULL); }
 185   int generic_signature_index() const            { return constMethod()->generic_signature_index(); }
 186   void set_generic_signature_index(int index)    { constMethod()->set_generic_signature_index(index); }
 187 
 188   // annotations support
 189   AnnotationArray* annotations() const           {
 190     return constMethod()->method_annotations();
 191   }
 192   AnnotationArray* parameter_annotations() const {
 193     return constMethod()->parameter_annotations();
 194   }
 195   AnnotationArray* annotation_default() const    {
 196     return constMethod()->default_annotations();
 197   }
 198   AnnotationArray* type_annotations() const      {
 199     return constMethod()->type_annotations();
 200   }
 201 
 202   // Helper routine: get klass name + "." + method name + signature as
 203   // C string, for the purpose of providing more useful NoSuchMethodErrors
 204   // and fatal error handling. The string is allocated in resource
 205   // area if a buffer is not provided by the caller.
 206   char* name_and_sig_as_C_string() const;
 207   char* name_and_sig_as_C_string(char* buf, int size) const;
 208 
 209   // Static routine in the situations we don't have a Method*
 210   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
 211   static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
 212 
 213   Bytecodes::Code java_code_at(int bci) const {
 214     return Bytecodes::java_code_at(this, bcp_from(bci));
 215   }
 216   Bytecodes::Code code_at(int bci) const {
 217     return Bytecodes::code_at(this, bcp_from(bci));
 218   }
 219 
 220   // JVMTI breakpoints
 221   Bytecodes::Code orig_bytecode_at(int bci) const;
 222   void        set_orig_bytecode_at(int bci, Bytecodes::Code code);
 223   void set_breakpoint(int bci);
 224   void clear_breakpoint(int bci);
 225   void clear_all_breakpoints();
 226   // Tracking number of breakpoints, for fullspeed debugging.
 227   // Only mutated by VM thread.
 228   u2   number_of_breakpoints()             const {
 229     MethodCounters* mcs = method_counters();
 230     if (mcs == NULL) {
 231       return 0;
 232     } else {
 233       return mcs->number_of_breakpoints();
 234     }
 235   }
 236   void incr_number_of_breakpoints(TRAPS)         {
 237     MethodCounters* mcs = get_method_counters(CHECK);
 238     if (mcs != NULL) {
 239       mcs->incr_number_of_breakpoints();
 240     }
 241   }
 242   void decr_number_of_breakpoints(TRAPS)         {
 243     MethodCounters* mcs = get_method_counters(CHECK);
 244     if (mcs != NULL) {
 245       mcs->decr_number_of_breakpoints();
 246     }
 247   }
 248   // Initialization only
 249   void clear_number_of_breakpoints()             {
 250     MethodCounters* mcs = method_counters();
 251     if (mcs != NULL) {
 252       mcs->clear_number_of_breakpoints();
 253     }
 254   }
 255 
 256   // index into InstanceKlass methods() array
 257   // note: also used by jfr
 258   u2 method_idnum() const           { return constMethod()->method_idnum(); }
 259   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }
 260 
 261   u2 orig_method_idnum() const           { return constMethod()->orig_method_idnum(); }
 262   void set_orig_method_idnum(u2 idnum)   { constMethod()->set_orig_method_idnum(idnum); }
 263 
 264   // code size
 265   int code_size() const                  { return constMethod()->code_size(); }
 266 
 267   // method size
 268   int method_size() const                        { return _method_size; }
 269   void set_method_size(int size) {
 270     assert(0 <= size && size < (1 << 16), "invalid method size");
 271     _method_size = size;
 272   }
 273 
 274   // constant pool for Klass* holding this method
 275   ConstantPool* constants() const              { return constMethod()->constants(); }
 276   void set_constants(ConstantPool* c)          { constMethod()->set_constants(c); }
 277 
 278   // max stack
 279   // return original max stack size for method verification
 280   int  verifier_max_stack() const                { return constMethod()->max_stack(); }
 281   int           max_stack() const                { return constMethod()->max_stack() + extra_stack_entries(); }
 282   void      set_max_stack(int size)              {        constMethod()->set_max_stack(size); }
 283 
 284   // max locals
 285   int  max_locals() const                        { return constMethod()->max_locals(); }
 286   void set_max_locals(int size)                  { constMethod()->set_max_locals(size); }
 287 
 288   int highest_comp_level() const;
 289   void set_highest_comp_level(int level);
 290   int highest_osr_comp_level() const;
 291   void set_highest_osr_comp_level(int level);
 292 
 293   // Count of times method was exited via exception while interpreting
 294   void interpreter_throwout_increment(TRAPS) {
 295     MethodCounters* mcs = get_method_counters(CHECK);
 296     if (mcs != NULL) {
 297       mcs->interpreter_throwout_increment();
 298     }
 299   }
 300 
 301   int  interpreter_throwout_count() const        {
 302     MethodCounters* mcs = method_counters();
 303     if (mcs == NULL) {
 304       return 0;
 305     } else {
 306       return mcs->interpreter_throwout_count();
 307     }
 308   }
 309 
 310   // size of parameters
 311   int  size_of_parameters() const                { return constMethod()->size_of_parameters(); }
 312   void set_size_of_parameters(int size)          { constMethod()->set_size_of_parameters(size); }
 313 
 314   bool has_stackmap_table() const {
 315     return constMethod()->has_stackmap_table();
 316   }
 317 
 318   Array<u1>* stackmap_data() const {
 319     return constMethod()->stackmap_data();
 320   }
 321 
 322   void set_stackmap_data(Array<u1>* sd) {
 323     constMethod()->set_stackmap_data(sd);
 324   }
 325 
 326   // exception handler table
 327   bool has_exception_handler() const
 328                              { return constMethod()->has_exception_handler(); }
 329   int exception_table_length() const
 330                              { return constMethod()->exception_table_length(); }
 331   ExceptionTableElement* exception_table_start() const
 332                              { return constMethod()->exception_table_start(); }
 333 
 334   // Finds the first entry point bci of an exception handler for an
 335   // exception of klass ex_klass thrown at throw_bci. A value of NULL
 336   // for ex_klass indicates that the exception klass is not known; in
 337   // this case it matches any constraint class. Returns -1 if the
 338   // exception cannot be handled in this method. The handler
 339   // constraint classes are loaded if necessary. Note that this may
 340   // throw an exception if loading of the constraint classes causes
 341   // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
 342   // If an exception is thrown, returns the bci of the
 343   // exception handler which caused the exception to be thrown, which
 344   // is needed for proper retries. See, for example,
 345   // InterpreterRuntime::exception_handler_for_exception.
 346   static int fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS);
 347 
 348   // method data access
 349   MethodData* method_data() const              {
 350     return _method_data;
 351   }
 352 
 353   void set_method_data(MethodData* data)       {
 354     // The store into method must be released. On platforms without
 355     // total store order (TSO) the reference may become visible before
 356     // the initialization of data otherwise.
 357     OrderAccess::release_store_ptr((volatile void *)&_method_data, data);
 358   }
 359 
 360   MethodCounters* method_counters() const {
 361     return _method_counters;
 362   }
 363 
 364   void clear_method_counters() {
 365     _method_counters = NULL;
 366   }
 367 
 368   bool init_method_counters(MethodCounters* counters) {
 369     // Try to install a pointer to MethodCounters, return true on success.
 370     return Atomic::cmpxchg_ptr(counters, (volatile void*)&_method_counters, NULL) == NULL;
 371   }
 372 
 373 #ifdef TIERED
 374   // We are reusing interpreter_invocation_count as a holder for the previous event count!
 375   // We can do that since interpreter_invocation_count is not used in tiered.
 376   int prev_event_count() const                   {
 377     if (method_counters() == NULL) {
 378       return 0;
 379     } else {
 380       return method_counters()->interpreter_invocation_count();
 381     }
 382   }
 383   void set_prev_event_count(int count) {
 384     MethodCounters* mcs = method_counters();
 385     if (mcs != NULL) {
 386       mcs->set_interpreter_invocation_count(count);
 387     }
 388   }
 389   jlong prev_time() const                        {
 390     MethodCounters* mcs = method_counters();
 391     return mcs == NULL ? 0 : mcs->prev_time();
 392   }
 393   void set_prev_time(jlong time) {
 394     MethodCounters* mcs = method_counters();
 395     if (mcs != NULL) {
 396       mcs->set_prev_time(time);
 397     }
 398   }
 399   float rate() const                             {
 400     MethodCounters* mcs = method_counters();
 401     return mcs == NULL ? 0 : mcs->rate();
 402   }
 403   void set_rate(float rate) {
 404     MethodCounters* mcs = method_counters();
 405     if (mcs != NULL) {
 406       mcs->set_rate(rate);
 407     }
 408   }
 409 #endif
 410 
 411   int invocation_count();
 412   int backedge_count();
 413 
 414   bool was_executed_more_than(int n);
 415   bool was_never_executed()                      { return !was_executed_more_than(0); }
 416 
 417   static void build_interpreter_method_data(methodHandle method, TRAPS);
 418 
 419   static MethodCounters* build_method_counters(Method* m, TRAPS);
 420 
 421   int interpreter_invocation_count() {
 422     if (TieredCompilation) {
 423       return invocation_count();
 424     } else {
 425       MethodCounters* mcs = method_counters();
 426       return (mcs == NULL) ? 0 : mcs->interpreter_invocation_count();
 427     }
 428   }
 429   int increment_interpreter_invocation_count(TRAPS) {
 430     if (TieredCompilation) ShouldNotReachHere();
 431     MethodCounters* mcs = get_method_counters(CHECK_0);
 432     return (mcs == NULL) ? 0 : mcs->increment_interpreter_invocation_count();
 433   }
 434 
 435 #ifndef PRODUCT
 436   int  compiled_invocation_count() const         { return _compiled_invocation_count;  }
 437   void set_compiled_invocation_count(int count)  { _compiled_invocation_count = count; }
 438 #endif // not PRODUCT
 439 
 440   // Clear (non-shared space) pointers which could not be relevant
 441   // if this (shared) method were mapped into another JVM.
 442   void remove_unshareable_info();
 443 
 444   // nmethod/verified compiler entry
 445   address verified_code_entry();
 446   bool check_code() const;      // Not inline to avoid circular ref
 447   nmethod* volatile code() const                 { assert( check_code(), "" ); return (nmethod *)OrderAccess::load_ptr_acquire(&_code); }
 448   void clear_code(bool acquire_lock = true);            // Clear out any compiled code
 449   static void set_code(methodHandle mh, nmethod* code);
 450   void set_adapter_entry(AdapterHandlerEntry* adapter) {  _adapter = adapter; }
 451   address get_i2c_entry();
 452   address get_c2i_entry();
 453   address get_c2i_unverified_entry();
 454   AdapterHandlerEntry* adapter() {  return _adapter; }
 455   // setup entry points
 456   void link_method(methodHandle method, TRAPS);
 457   // clear entry points. Used by sharing code
 458   void unlink_method();
 459 
 460   // vtable index
 461   enum VtableIndexFlag {
 462     // Valid vtable indexes are non-negative (>= 0).
 463     // These few negative values are used as sentinels.
 464     itable_index_max        = -10, // first itable index, growing downward
 465     pending_itable_index    = -9,  // itable index will be assigned
 466     invalid_vtable_index    = -4,  // distinct from any valid vtable index
 467     garbage_vtable_index    = -3,  // not yet linked; no vtable layout yet
 468     nonvirtual_vtable_index = -2   // there is no need for vtable dispatch
 469     // 6330203 Note:  Do not use -1, which was overloaded with many meanings.
 470   };
 471   DEBUG_ONLY(bool valid_vtable_index() const     { return _vtable_index >= nonvirtual_vtable_index; })
 472   bool has_vtable_index() const                  { return _vtable_index >= 0; }
 473   int  vtable_index() const                      { return _vtable_index; }
 474   void set_vtable_index(int index);
 475   DEBUG_ONLY(bool valid_itable_index() const     { return _vtable_index <= pending_itable_index; })
 476   bool has_itable_index() const                  { return _vtable_index <= itable_index_max; }
 477   int  itable_index() const                      { assert(valid_itable_index(), "");
 478                                                    return itable_index_max - _vtable_index; }
 479   void set_itable_index(int index);
 480 
 481   // interpreter entry
 482   address interpreter_entry() const              { return _i2i_entry; }
 483   // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
 484   void set_interpreter_entry(address entry)      { _i2i_entry = entry;  _from_interpreted_entry = entry; }
 485 
 486   // native function (used for native methods only)
 487   enum {
 488     native_bind_event_is_interesting = true
 489   };
 490   address native_function() const                { return *(native_function_addr()); }
 491   address critical_native_function();
 492 
 493   // Must specify a real function (not NULL).
 494   // Use clear_native_function() to unregister.
 495   void set_native_function(address function, bool post_event_flag);
 496   bool has_native_function() const;
 497   void clear_native_function();
 498 
 499   // signature handler (used for native methods only)
 500   address signature_handler() const              { return *(signature_handler_addr()); }
 501   void set_signature_handler(address handler);
 502 
 503   // Interpreter oopmap support
 504   void mask_for(int bci, InterpreterOopMap* mask);
 505 
 506 #ifndef PRODUCT
 507   // operations on invocation counter
 508   void print_invocation_count();
 509 #endif
 510 
 511   // byte codes
 512   void    set_code(address code)      { return constMethod()->set_code(code); }
 513   address code_base() const           { return constMethod()->code_base(); }
 514   bool    contains(address bcp) const { return constMethod()->contains(bcp); }
 515 
 516   // prints byte codes
 517   void print_codes() const            { print_codes_on(tty); }
 518   void print_codes_on(outputStream* st) const                      PRODUCT_RETURN;
 519   void print_codes_on(int from, int to, outputStream* st) const    PRODUCT_RETURN;
 520 
 521   // method parameters
 522   bool has_method_parameters() const
 523                          { return constMethod()->has_method_parameters(); }
 524   int method_parameters_length() const
 525                          { return constMethod()->method_parameters_length(); }
 526   MethodParametersElement* method_parameters_start() const
 527                           { return constMethod()->method_parameters_start(); }
 528 
 529   // checked exceptions
 530   int checked_exceptions_length() const
 531                          { return constMethod()->checked_exceptions_length(); }
 532   CheckedExceptionElement* checked_exceptions_start() const
 533                           { return constMethod()->checked_exceptions_start(); }
 534 
 535   // localvariable table
 536   bool has_localvariable_table() const
 537                           { return constMethod()->has_localvariable_table(); }
 538   int localvariable_table_length() const
 539                         { return constMethod()->localvariable_table_length(); }
 540   LocalVariableTableElement* localvariable_table_start() const
 541                          { return constMethod()->localvariable_table_start(); }
 542 
 543   bool has_linenumber_table() const
 544                               { return constMethod()->has_linenumber_table(); }
 545   u_char* compressed_linenumber_table() const
 546                        { return constMethod()->compressed_linenumber_table(); }
 547 
 548   // method holder (the Klass* holding this method)
 549   InstanceKlass* method_holder() const         { return constants()->pool_holder(); }
 550 
 551   void compute_size_of_parameters(Thread *thread); // word size of parameters (receiver if any + arguments)
 552   Symbol* klass_name() const;                    // returns the name of the method holder
 553   BasicType result_type() const;                 // type of the method result
 554   bool is_returning_oop() const                  { BasicType r = result_type(); return (r == T_OBJECT || r == T_ARRAY); }
 555   bool is_returning_fp() const                   { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }
 556 
 557   // Checked exceptions thrown by this method (resolved to mirrors)
 558   objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
 559 
 560   // Access flags
 561   bool is_public() const                         { return access_flags().is_public();      }
 562   bool is_private() const                        { return access_flags().is_private();     }
 563   bool is_protected() const                      { return access_flags().is_protected();   }
 564   bool is_package_private() const                { return !is_public() && !is_private() && !is_protected(); }
 565   bool is_static() const                         { return access_flags().is_static();      }
 566   bool is_final() const                          { return access_flags().is_final();       }
 567   bool is_synchronized() const                   { return access_flags().is_synchronized();}
 568   bool is_native() const                         { return access_flags().is_native();      }
 569   bool is_abstract() const                       { return access_flags().is_abstract();    }
 570   bool is_strict() const                         { return access_flags().is_strict();      }
 571   bool is_synthetic() const                      { return access_flags().is_synthetic();   }
 572 
 573   // returns true if contains only return operation
 574   bool is_empty_method() const;
 575 
 576   // returns true if this is a vanilla constructor
 577   bool is_vanilla_constructor() const;
 578 
 579   // checks method and its method holder
 580   bool is_final_method() const;
 581   bool is_final_method(AccessFlags class_access_flags) const;
 582   bool is_default_method() const;
 583 
 584   // true if method needs no dynamic dispatch (final and/or no vtable entry)
 585   bool can_be_statically_bound() const;
 586   bool can_be_statically_bound(AccessFlags class_access_flags) const;
 587 
 588   // returns true if the method has any backward branches.
 589   bool has_loops() {
 590     return access_flags().loops_flag_init() ? access_flags().has_loops() : compute_has_loops_flag();
 591   };
 592 
 593   bool compute_has_loops_flag();
 594 
 595   bool has_jsrs() {
 596     return access_flags().has_jsrs();
 597   };
 598   void set_has_jsrs() {
 599     _access_flags.set_has_jsrs();
 600   }
 601 
 602   // returns true if the method has any monitors.
 603   bool has_monitors() const                      { return is_synchronized() || access_flags().has_monitor_bytecodes(); }
 604   bool has_monitor_bytecodes() const             { return access_flags().has_monitor_bytecodes(); }
 605 
 606   void set_has_monitor_bytecodes()               { _access_flags.set_has_monitor_bytecodes(); }
 607 
 608   // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
 609   // propererly nest in the method. It might return false, even though they actually nest properly, since the info.
 610   // has not been computed yet.
 611   bool guaranteed_monitor_matching() const       { return access_flags().is_monitor_matching(); }
 612   void set_guaranteed_monitor_matching()         { _access_flags.set_monitor_matching(); }
 613 
 614   // returns true if the method is an accessor function (setter/getter).
 615   bool is_accessor() const;
 616 
 617   // returns true if the method does nothing but return a constant of primitive type
 618   bool is_constant_getter() const;
 619 
 620   // returns true if the method is an initializer (<init> or <clinit>).
 621   bool is_initializer() const;
 622 
 623   // returns true if the method is static OR if the classfile version < 51
 624   bool has_valid_initializer_flags() const;
 625 
 626   // returns true if the method name is <clinit> and the method has
 627   // valid static initializer flags.
 628   bool is_static_initializer() const;
 629 
 630   // returns true if the method name is <init>
 631   bool is_object_initializer() const;
 632 
 633   // compiled code support
 634   // NOTE: code() is inherently racy as deopt can be clearing code
 635   // simultaneously. Use with caution.
 636   bool has_compiled_code() const                 { return code() != NULL; }
 637 
 638   // sizing
 639   static int header_size()                       { return sizeof(Method)/HeapWordSize; }
 640   static int size(bool is_native);
 641   int size() const                               { return method_size(); }
 642 #if INCLUDE_SERVICES
 643   void collect_statistics(KlassSizeStats *sz) const;
 644 #endif
 645 
 646   // interpreter support
 647   static ByteSize const_offset()                 { return byte_offset_of(Method, _constMethod       ); }
 648   static ByteSize access_flags_offset()          { return byte_offset_of(Method, _access_flags      ); }
 649   static ByteSize from_compiled_offset()         { return byte_offset_of(Method, _from_compiled_entry); }
 650   static ByteSize code_offset()                  { return byte_offset_of(Method, _code); }
 651   static ByteSize method_data_offset()           {
 652     return byte_offset_of(Method, _method_data);
 653   }
 654   static ByteSize method_counters_offset()       {
 655     return byte_offset_of(Method, _method_counters);
 656   }
 657 #ifndef PRODUCT
 658   static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
 659 #endif // not PRODUCT
 660   static ByteSize native_function_offset()       { return in_ByteSize(sizeof(Method));                 }
 661   static ByteSize from_interpreted_offset()      { return byte_offset_of(Method, _from_interpreted_entry ); }
 662   static ByteSize interpreter_entry_offset()     { return byte_offset_of(Method, _i2i_entry ); }
 663   static ByteSize signature_handler_offset()     { return in_ByteSize(sizeof(Method) + wordSize);      }
 664   static ByteSize itable_index_offset()          { return byte_offset_of(Method, _vtable_index ); }
 665 
 666   // for code generation
 667   static int method_data_offset_in_bytes()       { return offset_of(Method, _method_data); }
 668   static int intrinsic_id_offset_in_bytes()      { return offset_of(Method, _intrinsic_id); }
 669   static int intrinsic_id_size_in_bytes()        { return sizeof(u1); }
 670 
 671   // Static methods that are used to implement member methods where an exposed this pointer
 672   // is needed due to possible GCs
 673   static objArrayHandle resolved_checked_exceptions_impl(Method* this_oop, TRAPS);
 674 
 675   // Returns the byte code index from the byte code pointer
 676   int     bci_from(address bcp) const;
 677   address bcp_from(int     bci) const;
 678   int validate_bci_from_bcx(intptr_t bcx) const;
 679 
 680   // Returns the line number for a bci if debugging information for the method is prowided,
 681   // -1 is returned otherwise.
 682   int line_number_from_bci(int bci) const;
 683 
 684   // Reflection support
 685   bool is_overridden_in(Klass* k) const;
 686 
 687   // Stack walking support
 688   bool is_ignored_by_security_stack_walk() const;
 689 
 690   // JSR 292 support
 691   bool is_method_handle_intrinsic() const;          // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
 692   bool is_compiled_lambda_form() const;             // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
 693   bool has_member_arg() const;                      // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
 694   static methodHandle make_method_handle_intrinsic(vmIntrinsics::ID iid, // _invokeBasic, _linkToVirtual
 695                                                    Symbol* signature, //anything at all
 696                                                    TRAPS);
 697   static Klass* check_non_bcp_klass(Klass* klass);
 698 
 699   // How many extra stack entries for invokedynamic when it's enabled
 700   static const int extra_stack_entries_for_jsr292 = 1;
 701 
 702   // this operates only on invoke methods:
 703   // presize interpreter frames for extra interpreter stack entries, if needed
 704   // Account for the extra appendix argument for invokehandle/invokedynamic
 705   static int extra_stack_entries() { return EnableInvokeDynamic ? extra_stack_entries_for_jsr292 : 0; }
 706   static int extra_stack_words();  // = extra_stack_entries() * Interpreter::stackElementSize
 707 
 708   // RedefineClasses() support:
 709   bool is_old() const                               { return access_flags().is_old(); }
 710   void set_is_old()                                 { _access_flags.set_is_old(); }
 711   bool is_obsolete() const                          { return access_flags().is_obsolete(); }
 712   void set_is_obsolete()                            { _access_flags.set_is_obsolete(); }
 713   bool is_deleted() const                           { return access_flags().is_deleted(); }
 714   void set_is_deleted()                             { _access_flags.set_is_deleted(); }
 715 
 716   bool is_running_emcp() const {
 717     // EMCP methods are old but not obsolete or deleted. Equivalent
 718     // Modulo Constant Pool means the method is equivalent except
 719     // the constant pool and instructions that access the constant
 720     // pool might be different.
 721     // If a breakpoint is set in a redefined method, its EMCP methods that are
 722     // still running must have a breakpoint also.
 723     return _running_emcp;
 724   }
 725 
 726   void set_running_emcp(bool x) {
 727     _running_emcp = x;
 728   }
 729 
 730   bool on_stack() const                             { return access_flags().on_stack(); }
 731   void set_on_stack(const bool value);
 732 
 733   // see the definition in Method*.cpp for the gory details
 734   bool should_not_be_cached() const;
 735 
 736   // JVMTI Native method prefixing support:
 737   bool is_prefixed_native() const                   { return access_flags().is_prefixed_native(); }
 738   void set_is_prefixed_native()                     { _access_flags.set_is_prefixed_native(); }
 739 
 740   // Rewriting support
 741   static methodHandle clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
 742                                           u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
 743 
 744   // jmethodID handling
 745   // Because the useful life-span of a jmethodID cannot be determined,
 746   // once created they are never reclaimed.  The methods to which they refer,
 747   // however, can be GC'ed away if the class is unloaded or if the method is
 748   // made obsolete or deleted -- in these cases, the jmethodID
 749   // refers to NULL (as is the case for any weak reference).
 750   static jmethodID make_jmethod_id(ClassLoaderData* loader_data, Method* mh);
 751   static void destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID mid);
 752 
 753   // Use resolve_jmethod_id() in situations where the caller is expected
 754   // to provide a valid jmethodID; the only sanity checks are in asserts;
 755   // result guaranteed not to be NULL.
 756   inline static Method* resolve_jmethod_id(jmethodID mid) {
 757     assert(mid != NULL, "JNI method id should not be null");
 758     return *((Method**)mid);
 759   }
 760 
 761   // Use checked_resolve_jmethod_id() in situations where the caller
 762   // should provide a valid jmethodID, but might not. NULL is returned
 763   // when the jmethodID does not refer to a valid method.
 764   static Method* checked_resolve_jmethod_id(jmethodID mid);
 765 
 766   static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
 767   static bool is_method_id(jmethodID mid);
 768 
 769   // Clear methods
 770   static void clear_jmethod_ids(ClassLoaderData* loader_data);
 771   static void print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
 772 
 773   // Get this method's jmethodID -- allocate if it doesn't exist
 774   jmethodID jmethod_id()                            { methodHandle this_h(this);
 775                                                       return InstanceKlass::get_jmethod_id(method_holder(), this_h); }
 776 
 777   // Lookup the jmethodID for this method.  Return NULL if not found.
 778   // NOTE that this function can be called from a signal handler
 779   // (see AsyncGetCallTrace support for Forte Analyzer) and this
 780   // needs to be async-safe. No allocation should be done and
 781   // so handles are not used to avoid deadlock.
 782   jmethodID find_jmethod_id_or_null()               { return method_holder()->jmethod_id_or_null(this); }
 783 
 784   // Support for inlining of intrinsic methods
 785   vmIntrinsics::ID intrinsic_id() const          { return (vmIntrinsics::ID) _intrinsic_id;           }
 786   void     set_intrinsic_id(vmIntrinsics::ID id) {                           _intrinsic_id = (u1) id; }
 787 
 788   // Helper routines for intrinsic_id() and vmIntrinsics::method().
 789   void init_intrinsic_id();     // updates from _none if a match
 790   void clear_jmethod_id(ClassLoaderData* loader_data);
 791 
 792   static vmSymbols::SID klass_id_for_intrinsics(Klass* holder);
 793 
 794   bool     jfr_towrite()                { return _jfr_towrite;              }
 795   void set_jfr_towrite(bool x)          {        _jfr_towrite = x;          }
 796   bool     caller_sensitive()           { return _caller_sensitive;         }
 797   void set_caller_sensitive(bool x)     {        _caller_sensitive = x;     }
 798   bool     force_inline()               { return _force_inline;             }
 799   void set_force_inline(bool x)         {        _force_inline = x;         }
 800   bool     dont_inline()                { return _dont_inline;              }
 801   void set_dont_inline(bool x)          {        _dont_inline = x;          }
 802   bool  is_hidden()                     { return _hidden;                   }
 803   void set_hidden(bool x)               {        _hidden = x;               }
 804   bool     has_injected_profile()       { return _has_injected_profile;     }
 805   void set_has_injected_profile(bool x) {        _has_injected_profile = x; }
 806 
 807   ConstMethod::MethodType method_type() const {
 808       return _constMethod->method_type();
 809   }
 810   bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
 811 
 812   // On-stack replacement support
 813   bool has_osr_nmethod(int level, bool match_level) {
 814    return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != NULL;
 815   }
 816 
 817   int mark_osr_nmethods() {
 818     return method_holder()->mark_osr_nmethods(this);
 819   }
 820 
 821   nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
 822     return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
 823   }
 824 
 825   // Inline cache support
 826   void cleanup_inline_caches();
 827 
 828   // Find if klass for method is loaded
 829   bool is_klass_loaded_by_klass_index(int klass_index) const;
 830   bool is_klass_loaded(int refinfo_index, bool must_be_resolved = false) const;
 831 
 832   // Indicates whether compilation failed earlier for this method, or
 833   // whether it is not compilable for another reason like having a
 834   // breakpoint set in it.
 835   bool  is_not_compilable(int comp_level = CompLevel_any) const;
 836   void set_not_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 837   void set_not_compilable_quietly(int comp_level = CompLevel_all) {
 838     set_not_compilable(comp_level, false);
 839   }
 840   bool  is_not_osr_compilable(int comp_level = CompLevel_any) const;
 841   void set_not_osr_compilable(int comp_level = CompLevel_all, bool report = true, const char* reason = NULL);
 842   void set_not_osr_compilable_quietly(int comp_level = CompLevel_all) {
 843     set_not_osr_compilable(comp_level, false);
 844   }
 845   bool is_always_compilable() const;
 846 
 847  private:
 848   void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
 849 
 850  public:
 851   MethodCounters* get_method_counters(TRAPS) {
 852     if (_method_counters == NULL) {
 853       build_method_counters(this, CHECK_AND_CLEAR_NULL);
 854     }
 855     return _method_counters;
 856   }
 857 
 858   bool   is_not_c1_compilable() const         { return access_flags().is_not_c1_compilable();  }
 859   void  set_not_c1_compilable()               {       _access_flags.set_not_c1_compilable();   }
 860   void clear_not_c1_compilable()              {       _access_flags.clear_not_c1_compilable(); }
 861   bool   is_not_c2_compilable() const         { return access_flags().is_not_c2_compilable();  }
 862   void  set_not_c2_compilable()               {       _access_flags.set_not_c2_compilable();   }
 863   void clear_not_c2_compilable()              {       _access_flags.clear_not_c2_compilable(); }
 864 
 865   bool    is_not_c1_osr_compilable() const    { return is_not_c1_compilable(); }  // don't waste an accessFlags bit
 866   void   set_not_c1_osr_compilable()          {       set_not_c1_compilable(); }  // don't waste an accessFlags bit
 867   void clear_not_c1_osr_compilable()          {     clear_not_c1_compilable(); }  // don't waste an accessFlags bit
 868   bool   is_not_c2_osr_compilable() const     { return access_flags().is_not_c2_osr_compilable();  }
 869   void  set_not_c2_osr_compilable()           {       _access_flags.set_not_c2_osr_compilable();   }
 870   void clear_not_c2_osr_compilable()          {       _access_flags.clear_not_c2_osr_compilable(); }
 871 
 872   // Background compilation support
 873   bool queued_for_compilation() const  { return access_flags().queued_for_compilation(); }
 874   void set_queued_for_compilation()    { _access_flags.set_queued_for_compilation();     }
 875   void clear_queued_for_compilation()  { _access_flags.clear_queued_for_compilation();   }
 876 
 877   // Resolve all classes in signature, return 'true' if successful
 878   static bool load_signature_classes(methodHandle m, TRAPS);
 879 
 880   // Return if true if not all classes references in signature, including return type, has been loaded
 881   static bool has_unloaded_classes_in_signature(methodHandle m, TRAPS);
 882 
 883   // Printing
 884   void print_short_name(outputStream* st = tty); // prints as klassname::methodname; Exposed so field engineers can debug VM
 885 #if INCLUDE_JVMTI
 886   void print_name(outputStream* st = tty); // prints as "virtual void foo(int)"; exposed for TraceRedefineClasses
 887 #else
 888   void print_name(outputStream* st = tty)        PRODUCT_RETURN; // prints as "virtual void foo(int)"
 889 #endif
 890 
 891   // Helper routine used for method sorting
 892   static void sort_methods(Array<Method*>* methods, bool idempotent = false, bool set_idnums = true);
 893 
 894   // Deallocation function for redefine classes or if an error occurs
 895   void deallocate_contents(ClassLoaderData* loader_data);
 896 
 897   // Printing
 898 #ifndef PRODUCT
 899   void print_on(outputStream* st) const;
 900 #endif
 901   void print_value_on(outputStream* st) const;
 902 
 903   const char* internal_name() const { return "{method}"; }
 904 
 905   // Check for valid method pointer
 906   static bool has_method_vptr(const void* ptr);
 907   bool is_valid_method() const;
 908 
 909   // Verify
 910   void verify() { verify_on(tty); }
 911   void verify_on(outputStream* st);
 912 
 913  private:
 914 
 915   // Inlined elements
 916   address* native_function_addr() const          { assert(is_native(), "must be native"); return (address*) (this+1); }
 917   address* signature_handler_addr() const        { return native_function_addr() + 1; }
 918 };
 919 
 920 
 921 // Utility class for compressing line number tables
 922 
 923 class CompressedLineNumberWriteStream: public CompressedWriteStream {
 924  private:
 925   int _bci;
 926   int _line;
 927  public:
 928   // Constructor
 929   CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
 930   CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
 931 
 932   // Write (bci, line number) pair to stream
 933   void write_pair_regular(int bci_delta, int line_delta);
 934 
 935   inline void write_pair_inline(int bci, int line) {
 936     int bci_delta = bci - _bci;
 937     int line_delta = line - _line;
 938     _bci = bci;
 939     _line = line;
 940     // Skip (0,0) deltas - they do not add information and conflict with terminator.
 941     if (bci_delta == 0 && line_delta == 0) return;
 942     // Check if bci is 5-bit and line number 3-bit unsigned.
 943     if (((bci_delta & ~0x1F) == 0) && ((line_delta & ~0x7) == 0)) {
 944       // Compress into single byte.
 945       jubyte value = ((jubyte) bci_delta << 3) | (jubyte) line_delta;
 946       // Check that value doesn't match escape character.
 947       if (value != 0xFF) {
 948         write_byte(value);
 949         return;
 950       }
 951     }
 952     write_pair_regular(bci_delta, line_delta);
 953   }
 954 
 955 // Windows AMD64 + Apr 2005 PSDK with /O2 generates bad code for write_pair.
 956 // Disabling optimization doesn't work for methods in header files
 957 // so we force it to call through the non-optimized version in the .cpp.
 958 // It's gross, but it's the only way we can ensure that all callers are
 959 // fixed.  _MSC_VER is defined by the windows compiler
 960 #if defined(_M_AMD64) && _MSC_VER >= 1400
 961   void write_pair(int bci, int line);
 962 #else
 963   void write_pair(int bci, int line) { write_pair_inline(bci, line); }
 964 #endif
 965 
 966   // Write end-of-stream marker
 967   void write_terminator()                        { write_byte(0); }
 968 };
 969 
 970 
 971 // Utility class for decompressing line number tables
 972 
 973 class CompressedLineNumberReadStream: public CompressedReadStream {
 974  private:
 975   int _bci;
 976   int _line;
 977  public:
 978   // Constructor
 979   CompressedLineNumberReadStream(u_char* buffer);
 980   // Read (bci, line number) pair from stream. Returns false at end-of-stream.
 981   bool read_pair();
 982   // Accessing bci and line number (after calling read_pair)
 983   int bci() const                               { return _bci; }
 984   int line() const                              { return _line; }
 985 };
 986 
 987 
 988 /// Fast Breakpoints.
 989 
 990 // If this structure gets more complicated (because bpts get numerous),
 991 // move it into its own header.
 992 
 993 // There is presently no provision for concurrent access
 994 // to breakpoint lists, which is only OK for JVMTI because
 995 // breakpoints are written only at safepoints, and are read
 996 // concurrently only outside of safepoints.
 997 
 998 class BreakpointInfo : public CHeapObj<mtClass> {
 999   friend class VMStructs;
1000  private:
1001   Bytecodes::Code  _orig_bytecode;
1002   int              _bci;
1003   u2               _name_index;       // of method
1004   u2               _signature_index;  // of method
1005   BreakpointInfo*  _next;             // simple storage allocation
1006 
1007  public:
1008   BreakpointInfo(Method* m, int bci);
1009 
1010   // accessors
1011   Bytecodes::Code orig_bytecode()                     { return _orig_bytecode; }
1012   void        set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
1013   int         bci()                                   { return _bci; }
1014 
1015   BreakpointInfo*          next() const               { return _next; }
1016   void                 set_next(BreakpointInfo* n)    { _next = n; }
1017 
1018   // helps for searchers
1019   bool match(const Method* m, int bci) {
1020     return bci == _bci && match(m);
1021   }
1022 
1023   bool match(const Method* m) {
1024     return _name_index == m->name_index() &&
1025       _signature_index == m->signature_index();
1026   }
1027 
1028   void set(Method* method);
1029   void clear(Method* method);
1030 };
1031 
1032 // Utility class for access exception handlers
1033 class ExceptionTable : public StackObj {
1034  private:
1035   ExceptionTableElement* _table;
1036   u2  _length;
1037 
1038  public:
1039   ExceptionTable(const Method* m) {
1040     if (m->has_exception_handler()) {
1041       _table = m->exception_table_start();
1042       _length = m->exception_table_length();
1043     } else {
1044       _table = NULL;
1045       _length = 0;
1046     }
1047   }
1048 
1049   int length() const {
1050     return _length;
1051   }
1052 
1053   u2 start_pc(int idx) const {
1054     assert(idx < _length, "out of bounds");
1055     return _table[idx].start_pc;
1056   }
1057 
1058   void set_start_pc(int idx, u2 value) {
1059     assert(idx < _length, "out of bounds");
1060     _table[idx].start_pc = value;
1061   }
1062 
1063   u2 end_pc(int idx) const {
1064     assert(idx < _length, "out of bounds");
1065     return _table[idx].end_pc;
1066   }
1067 
1068   void set_end_pc(int idx, u2 value) {
1069     assert(idx < _length, "out of bounds");
1070     _table[idx].end_pc = value;
1071   }
1072 
1073   u2 handler_pc(int idx) const {
1074     assert(idx < _length, "out of bounds");
1075     return _table[idx].handler_pc;
1076   }
1077 
1078   void set_handler_pc(int idx, u2 value) {
1079     assert(idx < _length, "out of bounds");
1080     _table[idx].handler_pc = value;
1081   }
1082 
1083   u2 catch_type_index(int idx) const {
1084     assert(idx < _length, "out of bounds");
1085     return _table[idx].catch_type_index;
1086   }
1087 
1088   void set_catch_type_index(int idx, u2 value) {
1089     assert(idx < _length, "out of bounds");
1090     _table[idx].catch_type_index = value;
1091   }
1092 };
1093 
1094 #endif // SHARE_VM_OOPS_METHODOOP_HPP