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 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/debugInfoRec.hpp"
  29 #include "gc_interface/collectedHeap.inline.hpp"
  30 #include "interpreter/bytecodeStream.hpp"
  31 #include "interpreter/bytecodeTracer.hpp"
  32 #include "interpreter/bytecodes.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "memory/gcLocker.hpp"
  36 #include "memory/generation.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/oopFactory.hpp"
  40 #include "oops/constMethod.hpp"
  41 #include "oops/methodData.hpp"
  42 #include "oops/method.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "oops/symbol.hpp"
  45 #include "prims/jvmtiExport.hpp"
  46 #include "prims/methodHandles.hpp"
  47 #include "prims/nativeLookup.hpp"
  48 #include "runtime/arguments.hpp"
  49 #include "runtime/compilationPolicy.hpp"
  50 #include "runtime/frame.inline.hpp"
  51 #include "runtime/handles.inline.hpp"
  52 #include "runtime/relocator.hpp"
  53 #include "runtime/sharedRuntime.hpp"
  54 #include "runtime/signature.hpp"
  55 #include "utilities/quickSort.hpp"
  56 #include "utilities/xmlstream.hpp"
  57 
  58 
  59 // Implementation of Method
  60 
  61 Method* Method::allocate(ClassLoaderData* loader_data,
  62                          int byte_code_size,
  63                          AccessFlags access_flags,
  64                          InlineTableSizes* sizes,
  65                          ConstMethod::MethodType method_type,
  66                          TRAPS) {
  67   assert(!access_flags.is_native() || byte_code_size == 0,
  68          "native methods should not contain byte codes");
  69   ConstMethod* cm = ConstMethod::allocate(loader_data,
  70                                           byte_code_size,
  71                                           sizes,
  72                                           method_type,
  73                                           CHECK_NULL);
  74 
  75   int size = Method::size(access_flags.is_native());
  76 
  77   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  78 }
  79 
  80 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  81   No_Safepoint_Verifier no_safepoint;
  82   set_constMethod(xconst);
  83   set_access_flags(access_flags);
  84   set_method_size(size);
  85 #ifdef CC_INTERP
  86   set_result_index(T_VOID);
  87 #endif
  88   set_intrinsic_id(vmIntrinsics::_none);
  89   set_jfr_towrite(false);
  90   set_force_inline(false);
  91   set_hidden(false);
  92   set_dont_inline(false);
  93   set_method_data(NULL);
  94   set_method_counters(NULL);
  95   set_vtable_index(Method::garbage_vtable_index);
  96 
  97   // Fix and bury in Method*
  98   set_interpreter_entry(NULL); // sets i2i entry and from_int
  99   set_adapter_entry(NULL);
 100   clear_code(); // from_c/from_i get set to c2i/i2i
 101 
 102   if (access_flags.is_native()) {
 103     clear_native_function();
 104     set_signature_handler(NULL);
 105   }
 106 
 107   NOT_PRODUCT(set_compiled_invocation_count(0);)
 108 }
 109 
 110 // Release Method*.  The nmethod will be gone when we get here because
 111 // we've walked the code cache.
 112 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 113   MetadataFactory::free_metadata(loader_data, constMethod());
 114   set_constMethod(NULL);
 115   MetadataFactory::free_metadata(loader_data, method_data());
 116   set_method_data(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_counters());
 118   set_method_counters(NULL);
 119   // The nmethod will be gone when we get here.
 120   if (code() != NULL) _code = NULL;
 121 }
 122 
 123 address Method::get_i2c_entry() {
 124   assert(_adapter != NULL, "must have");
 125   return _adapter->get_i2c_entry();
 126 }
 127 
 128 address Method::get_c2i_entry() {
 129   assert(_adapter != NULL, "must have");
 130   return _adapter->get_c2i_entry();
 131 }
 132 
 133 address Method::get_c2i_unverified_entry() {
 134   assert(_adapter != NULL, "must have");
 135   return _adapter->get_c2i_unverified_entry();
 136 }
 137 
 138 char* Method::name_and_sig_as_C_string() const {
 139   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 140 }
 141 
 142 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 143   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 144 }
 145 
 146 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 147   const char* klass_name = klass->external_name();
 148   int klass_name_len  = (int)strlen(klass_name);
 149   int method_name_len = method_name->utf8_length();
 150   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 151   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 152   strcpy(dest, klass_name);
 153   dest[klass_name_len] = '.';
 154   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 155   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 156   dest[len] = 0;
 157   return dest;
 158 }
 159 
 160 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 161   Symbol* klass_name = klass->name();
 162   klass_name->as_klass_external_name(buf, size);
 163   int len = (int)strlen(buf);
 164 
 165   if (len < size - 1) {
 166     buf[len++] = '.';
 167 
 168     method_name->as_C_string(&(buf[len]), size - len);
 169     len = (int)strlen(buf);
 170 
 171     signature->as_C_string(&(buf[len]), size - len);
 172   }
 173 
 174   return buf;
 175 }
 176 
 177 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 178   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 179   // access exception table
 180   ExceptionTable table(mh());
 181   int length = table.length();
 182   // iterate through all entries sequentially
 183   constantPoolHandle pool(THREAD, mh->constants());
 184   for (int i = 0; i < length; i ++) {
 185     //reacquire the table in case a GC happened
 186     ExceptionTable table(mh());
 187     int beg_bci = table.start_pc(i);
 188     int end_bci = table.end_pc(i);
 189     assert(beg_bci <= end_bci, "inconsistent exception table");
 190     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 191       // exception handler bci range covers throw_bci => investigate further
 192       int handler_bci = table.handler_pc(i);
 193       int klass_index = table.catch_type_index(i);
 194       if (klass_index == 0) {
 195         return handler_bci;
 196       } else if (ex_klass.is_null()) {
 197         return handler_bci;
 198       } else {
 199         // we know the exception class => get the constraint class
 200         // this may require loading of the constraint class; if verification
 201         // fails or some other exception occurs, return handler_bci
 202         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 203         KlassHandle klass = KlassHandle(THREAD, k);
 204         assert(klass.not_null(), "klass not loaded");
 205         if (ex_klass->is_subtype_of(klass())) {
 206           return handler_bci;
 207         }
 208       }
 209     }
 210   }
 211 
 212   return -1;
 213 }
 214 
 215 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 216 
 217   Thread* myThread    = Thread::current();
 218   methodHandle h_this(myThread, this);
 219 #ifdef ASSERT
 220   bool has_capability = myThread->is_VM_thread() ||
 221                         myThread->is_ConcurrentGC_thread() ||
 222                         myThread->is_GC_task_thread();
 223 
 224   if (!has_capability) {
 225     if (!VerifyStack && !VerifyLastFrame) {
 226       // verify stack calls this outside VM thread
 227       warning("oopmap should only be accessed by the "
 228               "VM, GC task or CMS threads (or during debugging)");
 229       InterpreterOopMap local_mask;
 230       method_holder()->mask_for(h_this, bci, &local_mask);
 231       local_mask.print();
 232     }
 233   }
 234 #endif
 235   method_holder()->mask_for(h_this, bci, mask);
 236   return;
 237 }
 238 
 239 
 240 int Method::bci_from(address bcp) const {
 241 #ifdef ASSERT
 242   { ResourceMark rm;
 243   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 244          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 245   }
 246 #endif
 247   return bcp - code_base();
 248 }
 249 
 250 
 251 // Return (int)bcx if it appears to be a valid BCI.
 252 // Return bci_from((address)bcx) if it appears to be a valid BCP.
 253 // Return -1 otherwise.
 254 // Used by profiling code, when invalid data is a possibility.
 255 // The caller is responsible for validating the Method* itself.
 256 int Method::validate_bci_from_bcx(intptr_t bcx) const {
 257   // keep bci as -1 if not a valid bci
 258   int bci = -1;
 259   if (bcx == 0 || (address)bcx == code_base()) {
 260     // code_size() may return 0 and we allow 0 here
 261     // the method may be native
 262     bci = 0;
 263   } else if (frame::is_bci(bcx)) {
 264     if (bcx < code_size()) {
 265       bci = (int)bcx;
 266     }
 267   } else if (contains((address)bcx)) {
 268     bci = (address)bcx - code_base();
 269   }
 270   // Assert that if we have dodged any asserts, bci is negative.
 271   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 272   return bci;
 273 }
 274 
 275 address Method::bcp_from(int bci) const {
 276   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), "illegal bci");
 277   address bcp = code_base() + bci;
 278   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 279   return bcp;
 280 }
 281 
 282 
 283 int Method::size(bool is_native) {
 284   // If native, then include pointers for native_function and signature_handler
 285   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 286   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 287   return align_object_size(header_size() + extra_words);
 288 }
 289 
 290 
 291 Symbol* Method::klass_name() const {
 292   Klass* k = method_holder();
 293   assert(k->is_klass(), "must be klass");
 294   InstanceKlass* ik = (InstanceKlass*) k;
 295   return ik->name();
 296 }
 297 
 298 
 299 // Attempt to return method oop to original state.  Clear any pointers
 300 // (to objects outside the shared spaces).  We won't be able to predict
 301 // where they should point in a new JVM.  Further initialize some
 302 // entries now in order allow them to be write protected later.
 303 
 304 void Method::remove_unshareable_info() {
 305   unlink_method();
 306 }
 307 
 308 
 309 bool Method::was_executed_more_than(int n) {
 310   // Invocation counter is reset when the Method* is compiled.
 311   // If the method has compiled code we therefore assume it has
 312   // be excuted more than n times.
 313   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 314     // interpreter doesn't bump invocation counter of trivial methods
 315     // compiler does not bump invocation counter of compiled methods
 316     return true;
 317   }
 318   else if ((method_counters() != NULL &&
 319             method_counters()->invocation_counter()->carry()) ||
 320            (method_data() != NULL &&
 321             method_data()->invocation_counter()->carry())) {
 322     // The carry bit is set when the counter overflows and causes
 323     // a compilation to occur.  We don't know how many times
 324     // the counter has been reset, so we simply assume it has
 325     // been executed more than n times.
 326     return true;
 327   } else {
 328     return invocation_count() > n;
 329   }
 330 }
 331 
 332 #ifndef PRODUCT
 333 void Method::print_invocation_count() {
 334   if (is_static()) tty->print("static ");
 335   if (is_final()) tty->print("final ");
 336   if (is_synchronized()) tty->print("synchronized ");
 337   if (is_native()) tty->print("native ");
 338   method_holder()->name()->print_symbol_on(tty);
 339   tty->print(".");
 340   name()->print_symbol_on(tty);
 341   signature()->print_symbol_on(tty);
 342 
 343   if (WizardMode) {
 344     // dump the size of the byte codes
 345     tty->print(" {%d}", code_size());
 346   }
 347   tty->cr();
 348 
 349   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 350   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 351   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 352   if (CountCompiledCalls) {
 353     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 354   }
 355 
 356 }
 357 #endif
 358 
 359 // Build a MethodData* object to hold information about this method
 360 // collected in the interpreter.
 361 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 362   // Do not profile method if current thread holds the pending list lock,
 363   // which avoids deadlock for acquiring the MethodData_lock.
 364   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 365     return;
 366   }
 367 
 368   // Grab a lock here to prevent multiple
 369   // MethodData*s from being created.
 370   MutexLocker ml(MethodData_lock, THREAD);
 371   if (method->method_data() == NULL) {
 372     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 373     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 374     method->set_method_data(method_data);
 375     if (PrintMethodData && (Verbose || WizardMode)) {
 376       ResourceMark rm(THREAD);
 377       tty->print("build_interpreter_method_data for ");
 378       method->print_name(tty);
 379       tty->cr();
 380       // At the end of the run, the MDO, full of data, will be dumped.
 381     }
 382   }
 383 }
 384 
 385 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 386   methodHandle mh(m);
 387   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
 388   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
 389   if (mh->method_counters() == NULL) {
 390     mh->set_method_counters(counters);
 391   } else {
 392     MetadataFactory::free_metadata(loader_data, counters);
 393   }
 394   return mh->method_counters();
 395 }
 396 
 397 void Method::cleanup_inline_caches() {
 398   // The current system doesn't use inline caches in the interpreter
 399   // => nothing to do (keep this method around for future use)
 400 }
 401 
 402 
 403 int Method::extra_stack_words() {
 404   // not an inline function, to avoid a header dependency on Interpreter
 405   return extra_stack_entries() * Interpreter::stackElementSize;
 406 }
 407 
 408 
 409 void Method::compute_size_of_parameters(Thread *thread) {
 410   ArgumentSizeComputer asc(signature());
 411   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 412 }
 413 
 414 #ifdef CC_INTERP
 415 void Method::set_result_index(BasicType type)          {
 416   _result_index = Interpreter::BasicType_as_index(type);
 417 }
 418 #endif
 419 
 420 BasicType Method::result_type() const {
 421   ResultTypeFinder rtf(signature());
 422   return rtf.type();
 423 }
 424 
 425 
 426 bool Method::is_empty_method() const {
 427   return  code_size() == 1
 428       && *code_base() == Bytecodes::_return;
 429 }
 430 
 431 
 432 bool Method::is_vanilla_constructor() const {
 433   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 434   // which only calls the superclass vanilla constructor and possibly does stores of
 435   // zero constants to local fields:
 436   //
 437   //   aload_0
 438   //   invokespecial
 439   //   indexbyte1
 440   //   indexbyte2
 441   //
 442   // followed by an (optional) sequence of:
 443   //
 444   //   aload_0
 445   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 446   //   putfield
 447   //   indexbyte1
 448   //   indexbyte2
 449   //
 450   // followed by:
 451   //
 452   //   return
 453 
 454   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 455   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 456   int size = code_size();
 457   // Check if size match
 458   if (size == 0 || size % 5 != 0) return false;
 459   address cb = code_base();
 460   int last = size - 1;
 461   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 462     // Does not call superclass default constructor
 463     return false;
 464   }
 465   // Check optional sequence
 466   for (int i = 4; i < last; i += 5) {
 467     if (cb[i] != Bytecodes::_aload_0) return false;
 468     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 469     if (cb[i+2] != Bytecodes::_putfield) return false;
 470   }
 471   return true;
 472 }
 473 
 474 
 475 bool Method::compute_has_loops_flag() {
 476   BytecodeStream bcs(this);
 477   Bytecodes::Code bc;
 478 
 479   while ((bc = bcs.next()) >= 0) {
 480     switch( bc ) {
 481       case Bytecodes::_ifeq:
 482       case Bytecodes::_ifnull:
 483       case Bytecodes::_iflt:
 484       case Bytecodes::_ifle:
 485       case Bytecodes::_ifne:
 486       case Bytecodes::_ifnonnull:
 487       case Bytecodes::_ifgt:
 488       case Bytecodes::_ifge:
 489       case Bytecodes::_if_icmpeq:
 490       case Bytecodes::_if_icmpne:
 491       case Bytecodes::_if_icmplt:
 492       case Bytecodes::_if_icmpgt:
 493       case Bytecodes::_if_icmple:
 494       case Bytecodes::_if_icmpge:
 495       case Bytecodes::_if_acmpeq:
 496       case Bytecodes::_if_acmpne:
 497       case Bytecodes::_goto:
 498       case Bytecodes::_jsr:
 499         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 500         break;
 501 
 502       case Bytecodes::_goto_w:
 503       case Bytecodes::_jsr_w:
 504         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 505         break;
 506     }
 507   }
 508   _access_flags.set_loops_flag_init();
 509   return _access_flags.has_loops();
 510 }
 511 
 512 
 513 bool Method::is_final_method() const {
 514   // %%% Should return true for private methods also,
 515   // since there is no way to override them.
 516   return is_final() || method_holder()->is_final();
 517 }
 518 
 519 
 520 bool Method::is_strict_method() const {
 521   return is_strict();
 522 }
 523 
 524 
 525 bool Method::can_be_statically_bound() const {
 526   if (is_final_method())  return true;
 527   return vtable_index() == nonvirtual_vtable_index;
 528 }
 529 
 530 
 531 bool Method::is_accessor() const {
 532   if (code_size() != 5) return false;
 533   if (size_of_parameters() != 1) return false;
 534   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 535   if (java_code_at(1) != Bytecodes::_getfield) return false;
 536   if (java_code_at(4) != Bytecodes::_areturn &&
 537       java_code_at(4) != Bytecodes::_ireturn ) return false;
 538   return true;
 539 }
 540 
 541 
 542 bool Method::is_initializer() const {
 543   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 544 }
 545 
 546 bool Method::has_valid_initializer_flags() const {
 547   return (is_static() ||
 548           method_holder()->major_version() < 51);
 549 }
 550 
 551 bool Method::is_static_initializer() const {
 552   // For classfiles version 51 or greater, ensure that the clinit method is
 553   // static.  Non-static methods with the name "<clinit>" are not static
 554   // initializers. (older classfiles exempted for backward compatibility)
 555   return name() == vmSymbols::class_initializer_name() &&
 556          has_valid_initializer_flags();
 557 }
 558 
 559 
 560 objArrayHandle Method::resolved_checked_exceptions_impl(Method* this_oop, TRAPS) {
 561   int length = this_oop->checked_exceptions_length();
 562   if (length == 0) {  // common case
 563     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 564   } else {
 565     methodHandle h_this(THREAD, this_oop);
 566     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 567     objArrayHandle mirrors (THREAD, m_oop);
 568     for (int i = 0; i < length; i++) {
 569       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 570       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 571       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 572       mirrors->obj_at_put(i, k->java_mirror());
 573     }
 574     return mirrors;
 575   }
 576 };
 577 
 578 
 579 int Method::line_number_from_bci(int bci) const {
 580   if (bci == SynchronizationEntryBCI) bci = 0;
 581   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 582   int best_bci  =  0;
 583   int best_line = -1;
 584 
 585   if (has_linenumber_table()) {
 586     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 587     // Not necessarily sorted and not necessarily one-to-one.
 588     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 589     while (stream.read_pair()) {
 590       if (stream.bci() == bci) {
 591         // perfect match
 592         return stream.line();
 593       } else {
 594         // update best_bci/line
 595         if (stream.bci() < bci && stream.bci() >= best_bci) {
 596           best_bci  = stream.bci();
 597           best_line = stream.line();
 598         }
 599       }
 600     }
 601   }
 602   return best_line;
 603 }
 604 
 605 
 606 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 607   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 608     Thread *thread = Thread::current();
 609     Symbol* klass_name = constants()->klass_name_at(klass_index);
 610     Handle loader(thread, method_holder()->class_loader());
 611     Handle prot  (thread, method_holder()->protection_domain());
 612     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 613   } else {
 614     return true;
 615   }
 616 }
 617 
 618 
 619 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 620   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 621   if (must_be_resolved) {
 622     // Make sure klass is resolved in constantpool.
 623     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 624   }
 625   return is_klass_loaded_by_klass_index(klass_index);
 626 }
 627 
 628 
 629 void Method::set_native_function(address function, bool post_event_flag) {
 630   assert(function != NULL, "use clear_native_function to unregister natives");
 631   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 632   address* native_function = native_function_addr();
 633 
 634   // We can see racers trying to place the same native function into place. Once
 635   // is plenty.
 636   address current = *native_function;
 637   if (current == function) return;
 638   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 639       function != NULL) {
 640     // native_method_throw_unsatisfied_link_error_entry() should only
 641     // be passed when post_event_flag is false.
 642     assert(function !=
 643       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 644       "post_event_flag mis-match");
 645 
 646     // post the bind event, and possible change the bind function
 647     JvmtiExport::post_native_method_bind(this, &function);
 648   }
 649   *native_function = function;
 650   // This function can be called more than once. We must make sure that we always
 651   // use the latest registered method -> check if a stub already has been generated.
 652   // If so, we have to make it not_entrant.
 653   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 654   if (nm != NULL) {
 655     nm->make_not_entrant();
 656   }
 657 }
 658 
 659 
 660 bool Method::has_native_function() const {
 661   if (is_method_handle_intrinsic())
 662     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 663   address func = native_function();
 664   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 665 }
 666 
 667 
 668 void Method::clear_native_function() {
 669   // Note: is_method_handle_intrinsic() is allowed here.
 670   set_native_function(
 671     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 672     !native_bind_event_is_interesting);
 673   clear_code();
 674 }
 675 
 676 address Method::critical_native_function() {
 677   methodHandle mh(this);
 678   return NativeLookup::lookup_critical_entry(mh);
 679 }
 680 
 681 
 682 void Method::set_signature_handler(address handler) {
 683   address* signature_handler =  signature_handler_addr();
 684   *signature_handler = handler;
 685 }
 686 
 687 
 688 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 689   if (PrintCompilation && report) {
 690     ttyLocker ttyl;
 691     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 692     if (comp_level == CompLevel_all) {
 693       tty->print("all levels ");
 694     } else {
 695       tty->print("levels ");
 696       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 697         tty->print("%d ", i);
 698       }
 699     }
 700     this->print_short_name(tty);
 701     int size = this->code_size();
 702     if (size > 0) {
 703       tty->print(" (%d bytes)", size);
 704     }
 705     if (reason != NULL) {
 706       tty->print("   %s", reason);
 707     }
 708     tty->cr();
 709   }
 710   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 711     ttyLocker ttyl;
 712     xtty->begin_elem("make_not_%scompilable thread='" UINTX_FORMAT "'",
 713                      is_osr ? "osr_" : "", os::current_thread_id());
 714     if (reason != NULL) {
 715       xtty->print(" reason=\'%s\'", reason);
 716     }
 717     xtty->method(this);
 718     xtty->stamp();
 719     xtty->end_elem();
 720   }
 721 }
 722 
 723 bool Method::is_always_compilable() const {
 724   // Generated adapters must be compiled
 725   if (is_method_handle_intrinsic() && is_synthetic()) {
 726     assert(!is_not_c1_compilable(), "sanity check");
 727     assert(!is_not_c2_compilable(), "sanity check");
 728     return true;
 729   }
 730 
 731   return false;
 732 }
 733 
 734 bool Method::is_not_compilable(int comp_level) const {
 735   if (number_of_breakpoints() > 0)
 736     return true;
 737   if (is_always_compilable())
 738     return false;
 739   if (comp_level == CompLevel_any)
 740     return is_not_c1_compilable() || is_not_c2_compilable();
 741   if (is_c1_compile(comp_level))
 742     return is_not_c1_compilable();
 743   if (is_c2_compile(comp_level))
 744     return is_not_c2_compilable();
 745   return false;
 746 }
 747 
 748 // call this when compiler finds that this method is not compilable
 749 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 750   if (is_always_compilable()) {
 751     // Don't mark a method which should be always compilable
 752     return;
 753   }
 754   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 755   if (comp_level == CompLevel_all) {
 756     set_not_c1_compilable();
 757     set_not_c2_compilable();
 758   } else {
 759     if (is_c1_compile(comp_level))
 760       set_not_c1_compilable();
 761     if (is_c2_compile(comp_level))
 762       set_not_c2_compilable();
 763   }
 764   CompilationPolicy::policy()->disable_compilation(this);
 765   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 766 }
 767 
 768 bool Method::is_not_osr_compilable(int comp_level) const {
 769   if (is_not_compilable(comp_level))
 770     return true;
 771   if (comp_level == CompLevel_any)
 772     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 773   if (is_c1_compile(comp_level))
 774     return is_not_c1_osr_compilable();
 775   if (is_c2_compile(comp_level))
 776     return is_not_c2_osr_compilable();
 777   return false;
 778 }
 779 
 780 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 781   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 782   if (comp_level == CompLevel_all) {
 783     set_not_c1_osr_compilable();
 784     set_not_c2_osr_compilable();
 785   } else {
 786     if (is_c1_compile(comp_level))
 787       set_not_c1_osr_compilable();
 788     if (is_c2_compile(comp_level))
 789       set_not_c2_osr_compilable();
 790   }
 791   CompilationPolicy::policy()->disable_compilation(this);
 792   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 793 }
 794 
 795 // Revert to using the interpreter and clear out the nmethod
 796 void Method::clear_code() {
 797 
 798   // this may be NULL if c2i adapters have not been made yet
 799   // Only should happen at allocate time.
 800   if (_adapter == NULL) {
 801     _from_compiled_entry    = NULL;
 802   } else {
 803     _from_compiled_entry    = _adapter->get_c2i_entry();
 804   }
 805   OrderAccess::storestore();
 806   _from_interpreted_entry = _i2i_entry;
 807   OrderAccess::storestore();
 808   _code = NULL;
 809 }
 810 
 811 // Called by class data sharing to remove any entry points (which are not shared)
 812 void Method::unlink_method() {
 813   _code = NULL;
 814   _i2i_entry = NULL;
 815   _from_interpreted_entry = NULL;
 816   if (is_native()) {
 817     *native_function_addr() = NULL;
 818     set_signature_handler(NULL);
 819   }
 820   NOT_PRODUCT(set_compiled_invocation_count(0);)
 821   _adapter = NULL;
 822   _from_compiled_entry = NULL;
 823 
 824   // In case of DumpSharedSpaces, _method_data should always be NULL.
 825   //
 826   // During runtime (!DumpSharedSpaces), when we are cleaning a
 827   // shared class that failed to load, this->link_method() may
 828   // have already been called (before an exception happened), so
 829   // this->_method_data may not be NULL.
 830   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 831 
 832   set_method_data(NULL);
 833   set_method_counters(NULL);
 834 }
 835 
 836 // Called when the method_holder is getting linked. Setup entrypoints so the method
 837 // is ready to be called from interpreter, compiler, and vtables.
 838 void Method::link_method(methodHandle h_method, TRAPS) {
 839   // If the code cache is full, we may reenter this function for the
 840   // leftover methods that weren't linked.
 841   if (_i2i_entry != NULL) return;
 842 
 843   assert(_adapter == NULL, "init'd to NULL" );
 844   assert( _code == NULL, "nothing compiled yet" );
 845 
 846   // Setup interpreter entrypoint
 847   assert(this == h_method(), "wrong h_method()" );
 848   address entry = Interpreter::entry_for_method(h_method);
 849   assert(entry != NULL, "interpreter entry must be non-null");
 850   // Sets both _i2i_entry and _from_interpreted_entry
 851   set_interpreter_entry(entry);
 852 
 853   // Don't overwrite already registered native entries.
 854   if (is_native() && !has_native_function()) {
 855     set_native_function(
 856       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 857       !native_bind_event_is_interesting);
 858   }
 859 
 860   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 861   // special handling of vtables.  An alternative is to make adapters more
 862   // lazily by calling make_adapter() from from_compiled_entry() for the
 863   // normal calls.  For vtable calls life gets more complicated.  When a
 864   // call-site goes mega-morphic we need adapters in all methods which can be
 865   // called from the vtable.  We need adapters on such methods that get loaded
 866   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 867   // problem we'll make these lazily later.
 868   (void) make_adapters(h_method, CHECK);
 869 
 870   // ONLY USE the h_method now as make_adapter may have blocked
 871 
 872 }
 873 
 874 address Method::make_adapters(methodHandle mh, TRAPS) {
 875   // Adapters for compiled code are made eagerly here.  They are fairly
 876   // small (generally < 100 bytes) and quick to make (and cached and shared)
 877   // so making them eagerly shouldn't be too expensive.
 878   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 879   if (adapter == NULL ) {
 880     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 881   }
 882 
 883   mh->set_adapter_entry(adapter);
 884   mh->_from_compiled_entry = adapter->get_c2i_entry();
 885   return adapter->get_c2i_entry();
 886 }
 887 
 888 // The verified_code_entry() must be called when a invoke is resolved
 889 // on this method.
 890 
 891 // It returns the compiled code entry point, after asserting not null.
 892 // This function is called after potential safepoints so that nmethod
 893 // or adapter that it points to is still live and valid.
 894 // This function must not hit a safepoint!
 895 address Method::verified_code_entry() {
 896   debug_only(No_Safepoint_Verifier nsv;)
 897   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 898   if (code == NULL && UseCodeCacheFlushing) {
 899     nmethod *saved_code = CodeCache::reanimate_saved_code(this);
 900     if (saved_code != NULL) {
 901       methodHandle method(this);
 902       assert( ! saved_code->is_osr_method(), "should not get here for osr" );
 903       set_code( method, saved_code );
 904     }
 905   }
 906 
 907   assert(_from_compiled_entry != NULL, "must be set");
 908   return _from_compiled_entry;
 909 }
 910 
 911 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 912 // (could be racing a deopt).
 913 // Not inline to avoid circular ref.
 914 bool Method::check_code() const {
 915   // cached in a register or local.  There's a race on the value of the field.
 916   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 917   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 918 }
 919 
 920 // Install compiled code.  Instantly it can execute.
 921 void Method::set_code(methodHandle mh, nmethod *code) {
 922   assert( code, "use clear_code to remove code" );
 923   assert( mh->check_code(), "" );
 924 
 925   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 926 
 927   // These writes must happen in this order, because the interpreter will
 928   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 929   // which jumps to _from_compiled_entry.
 930   mh->_code = code;             // Assign before allowing compiled code to exec
 931 
 932   int comp_level = code->comp_level();
 933   // In theory there could be a race here. In practice it is unlikely
 934   // and not worth worrying about.
 935   if (comp_level > mh->highest_comp_level()) {
 936     mh->set_highest_comp_level(comp_level);
 937   }
 938 
 939   OrderAccess::storestore();
 940 #ifdef SHARK
 941   mh->_from_interpreted_entry = code->insts_begin();
 942 #else //!SHARK
 943   mh->_from_compiled_entry = code->verified_entry_point();
 944   OrderAccess::storestore();
 945   // Instantly compiled code can execute.
 946   if (!mh->is_method_handle_intrinsic())
 947     mh->_from_interpreted_entry = mh->get_i2c_entry();
 948 #endif //!SHARK
 949 }
 950 
 951 
 952 bool Method::is_overridden_in(Klass* k) const {
 953   InstanceKlass* ik = InstanceKlass::cast(k);
 954 
 955   if (ik->is_interface()) return false;
 956 
 957   // If method is an interface, we skip it - except if it
 958   // is a miranda method
 959   if (method_holder()->is_interface()) {
 960     // Check that method is not a miranda method
 961     if (ik->lookup_method(name(), signature()) == NULL) {
 962       // No implementation exist - so miranda method
 963       return false;
 964     }
 965     return true;
 966   }
 967 
 968   assert(ik->is_subclass_of(method_holder()), "should be subklass");
 969   assert(ik->vtable() != NULL, "vtable should exist");
 970   if (vtable_index() == nonvirtual_vtable_index) {
 971     return false;
 972   } else {
 973     Method* vt_m = ik->method_at_vtable(vtable_index());
 974     return vt_m != this;
 975   }
 976 }
 977 
 978 
 979 // give advice about whether this Method* should be cached or not
 980 bool Method::should_not_be_cached() const {
 981   if (is_old()) {
 982     // This method has been redefined. It is either EMCP or obsolete
 983     // and we don't want to cache it because that would pin the method
 984     // down and prevent it from being collectible if and when it
 985     // finishes executing.
 986     return true;
 987   }
 988 
 989   // caching this method should be just fine
 990   return false;
 991 }
 992 
 993 
 994 /**
 995  *  Returns true if this is one of the specially treated methods for
 996  *  security related stack walks (like Reflection.getCallerClass).
 997  */
 998 bool Method::is_ignored_by_security_stack_walk() const {
 999   const bool use_new_reflection = JDK_Version::is_gte_jdk14x_version() && UseNewReflection;
1000 
1001   if (intrinsic_id() == vmIntrinsics::_invoke) {
1002     // This is Method.invoke() -- ignore it
1003     return true;
1004   }
1005   if (use_new_reflection &&
1006       method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1007     // This is an auxilary frame -- ignore it
1008     return true;
1009   }
1010   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1011     // This is an internal adapter frame for method handles -- ignore it
1012     return true;
1013   }
1014   return false;
1015 }
1016 
1017 
1018 // Constant pool structure for invoke methods:
1019 enum {
1020   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1021   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1022   _imcp_limit
1023 };
1024 
1025 // Test if this method is an MH adapter frame generated by Java code.
1026 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1027 bool Method::is_compiled_lambda_form() const {
1028   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1029 }
1030 
1031 // Test if this method is an internal MH primitive method.
1032 bool Method::is_method_handle_intrinsic() const {
1033   vmIntrinsics::ID iid = intrinsic_id();
1034   return (MethodHandles::is_signature_polymorphic(iid) &&
1035           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1036 }
1037 
1038 bool Method::has_member_arg() const {
1039   vmIntrinsics::ID iid = intrinsic_id();
1040   return (MethodHandles::is_signature_polymorphic(iid) &&
1041           MethodHandles::has_member_arg(iid));
1042 }
1043 
1044 // Make an instance of a signature-polymorphic internal MH primitive.
1045 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1046                                                          Symbol* signature,
1047                                                          TRAPS) {
1048   ResourceMark rm;
1049   methodHandle empty;
1050 
1051   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1052   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1053   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1054   if (TraceMethodHandles) {
1055     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1056   }
1057 
1058   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1059   name->increment_refcount();
1060   signature->increment_refcount();
1061 
1062   int cp_length = _imcp_limit;
1063   ClassLoaderData* loader_data = holder->class_loader_data();
1064   constantPoolHandle cp;
1065   {
1066     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1067     cp = constantPoolHandle(THREAD, cp_oop);
1068   }
1069   cp->set_pool_holder(InstanceKlass::cast(holder()));
1070   cp->symbol_at_put(_imcp_invoke_name,       name);
1071   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1072   cp->set_has_preresolution();
1073 
1074   // decide on access bits:  public or not?
1075   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1076   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1077   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1078   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1079 
1080   methodHandle m;
1081   {
1082     InlineTableSizes sizes;
1083     Method* m_oop = Method::allocate(loader_data, 0,
1084                                      accessFlags_from(flags_bits), &sizes,
1085                                      ConstMethod::NORMAL, CHECK_(empty));
1086     m = methodHandle(THREAD, m_oop);
1087   }
1088   m->set_constants(cp());
1089   m->set_name_index(_imcp_invoke_name);
1090   m->set_signature_index(_imcp_invoke_signature);
1091   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1092   assert(m->signature() == signature, "");
1093 #ifdef CC_INTERP
1094   ResultTypeFinder rtf(signature);
1095   m->set_result_index(rtf.type());
1096 #endif
1097   m->compute_size_of_parameters(THREAD);
1098   m->init_intrinsic_id();
1099   assert(m->is_method_handle_intrinsic(), "");
1100 #ifdef ASSERT
1101   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1102   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1103   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1104 #endif //ASSERT
1105 
1106   // Finally, set up its entry points.
1107   assert(m->can_be_statically_bound(), "");
1108   m->set_vtable_index(Method::nonvirtual_vtable_index);
1109   m->link_method(m, CHECK_(empty));
1110 
1111   if (TraceMethodHandles && (Verbose || WizardMode))
1112     m->print_on(tty);
1113 
1114   return m;
1115 }
1116 
1117 Klass* Method::check_non_bcp_klass(Klass* klass) {
1118   if (klass != NULL && klass->class_loader() != NULL) {
1119     if (klass->oop_is_objArray())
1120       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1121     return klass;
1122   }
1123   return NULL;
1124 }
1125 
1126 
1127 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1128                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1129   // Code below does not work for native methods - they should never get rewritten anyway
1130   assert(!m->is_native(), "cannot rewrite native methods");
1131   // Allocate new Method*
1132   AccessFlags flags = m->access_flags();
1133 
1134   ConstMethod* cm = m->constMethod();
1135   int checked_exceptions_len = cm->checked_exceptions_length();
1136   int localvariable_len = cm->localvariable_table_length();
1137   int exception_table_len = cm->exception_table_length();
1138   int method_parameters_len = cm->method_parameters_length();
1139   int method_annotations_len = cm->method_annotations_length();
1140   int parameter_annotations_len = cm->parameter_annotations_length();
1141   int type_annotations_len = cm->type_annotations_length();
1142   int default_annotations_len = cm->default_annotations_length();
1143 
1144   InlineTableSizes sizes(
1145       localvariable_len,
1146       new_compressed_linenumber_size,
1147       exception_table_len,
1148       checked_exceptions_len,
1149       method_parameters_len,
1150       cm->generic_signature_index(),
1151       method_annotations_len,
1152       parameter_annotations_len,
1153       type_annotations_len,
1154       default_annotations_len,
1155       0);
1156 
1157   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1158   Method* newm_oop = Method::allocate(loader_data,
1159                                       new_code_length,
1160                                       flags,
1161                                       &sizes,
1162                                       m->method_type(),
1163                                       CHECK_(methodHandle()));
1164   methodHandle newm (THREAD, newm_oop);
1165   int new_method_size = newm->method_size();
1166 
1167   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1168   ConstMethod* newcm = newm->constMethod();
1169   int new_const_method_size = newm->constMethod()->size();
1170 
1171   memcpy(newm(), m(), sizeof(Method));
1172 
1173   // Create shallow copy of ConstMethod.
1174   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1175 
1176   // Reset correct method/const method, method size, and parameter info
1177   newm->set_constMethod(newcm);
1178   newm->constMethod()->set_code_size(new_code_length);
1179   newm->constMethod()->set_constMethod_size(new_const_method_size);
1180   newm->set_method_size(new_method_size);
1181   assert(newm->code_size() == new_code_length, "check");
1182   assert(newm->method_parameters_length() == method_parameters_len, "check");
1183   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1184   assert(newm->exception_table_length() == exception_table_len, "check");
1185   assert(newm->localvariable_table_length() == localvariable_len, "check");
1186   // Copy new byte codes
1187   memcpy(newm->code_base(), new_code, new_code_length);
1188   // Copy line number table
1189   if (new_compressed_linenumber_size > 0) {
1190     memcpy(newm->compressed_linenumber_table(),
1191            new_compressed_linenumber_table,
1192            new_compressed_linenumber_size);
1193   }
1194   // Copy method_parameters
1195   if (method_parameters_len > 0) {
1196     memcpy(newm->method_parameters_start(),
1197            m->method_parameters_start(),
1198            method_parameters_len * sizeof(MethodParametersElement));
1199   }
1200   // Copy checked_exceptions
1201   if (checked_exceptions_len > 0) {
1202     memcpy(newm->checked_exceptions_start(),
1203            m->checked_exceptions_start(),
1204            checked_exceptions_len * sizeof(CheckedExceptionElement));
1205   }
1206   // Copy exception table
1207   if (exception_table_len > 0) {
1208     memcpy(newm->exception_table_start(),
1209            m->exception_table_start(),
1210            exception_table_len * sizeof(ExceptionTableElement));
1211   }
1212   // Copy local variable number table
1213   if (localvariable_len > 0) {
1214     memcpy(newm->localvariable_table_start(),
1215            m->localvariable_table_start(),
1216            localvariable_len * sizeof(LocalVariableTableElement));
1217   }
1218   // Copy stackmap table
1219   if (m->has_stackmap_table()) {
1220     int code_attribute_length = m->stackmap_data()->length();
1221     Array<u1>* stackmap_data =
1222       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1223     memcpy((void*)stackmap_data->adr_at(0),
1224            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1225     newm->set_stackmap_data(stackmap_data);
1226   }
1227 
1228   // copy annotations over to new method
1229   newcm->copy_annotations_from(cm);
1230   return newm;
1231 }
1232 
1233 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1234   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1235   // because we are not loading from core libraries
1236   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1237   // which does not use the class default class loader so we check for its loader here
1238   InstanceKlass* ik = InstanceKlass::cast(holder);
1239   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1240     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1241   }
1242 
1243   // see if the klass name is well-known:
1244   Symbol* klass_name = ik->name();
1245   return vmSymbols::find_sid(klass_name);
1246 }
1247 
1248 void Method::init_intrinsic_id() {
1249   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1250   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1251   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1252   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1253 
1254   // the klass name is well-known:
1255   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1256   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1257 
1258   // ditto for method and signature:
1259   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1260   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1261       && name_id == vmSymbols::NO_SID)
1262     return;
1263   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1264   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1265       && sig_id == vmSymbols::NO_SID)  return;
1266   jshort flags = access_flags().as_short();
1267 
1268   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1269   if (id != vmIntrinsics::_none) {
1270     set_intrinsic_id(id);
1271     return;
1272   }
1273 
1274   // A few slightly irregular cases:
1275   switch (klass_id) {
1276   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1277     // Second chance: check in regular Math.
1278     switch (name_id) {
1279     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1280     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1281     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1282       // pretend it is the corresponding method in the non-strict class:
1283       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1284       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1285       break;
1286     }
1287     break;
1288 
1289   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1290   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1291     if (!is_native())  break;
1292     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1293     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1294       id = vmIntrinsics::_none;
1295     break;
1296   }
1297 
1298   if (id != vmIntrinsics::_none) {
1299     // Set up its iid.  It is an alias method.
1300     set_intrinsic_id(id);
1301     return;
1302   }
1303 }
1304 
1305 // These two methods are static since a GC may move the Method
1306 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1307   if (THREAD->is_Compiler_thread()) {
1308     // There is nothing useful this routine can do from within the Compile thread.
1309     // Hopefully, the signature contains only well-known classes.
1310     // We could scan for this and return true/false, but the caller won't care.
1311     return false;
1312   }
1313   bool sig_is_loaded = true;
1314   Handle class_loader(THREAD, m->method_holder()->class_loader());
1315   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1316   ResourceMark rm(THREAD);
1317   Symbol*  signature = m->signature();
1318   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1319     if (ss.is_object()) {
1320       Symbol* sym = ss.as_symbol(CHECK_(false));
1321       Symbol*  name  = sym;
1322       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1323                                              protection_domain, THREAD);
1324       // We are loading classes eagerly. If a ClassNotFoundException or
1325       // a LinkageError was generated, be sure to ignore it.
1326       if (HAS_PENDING_EXCEPTION) {
1327         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1328             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1329           CLEAR_PENDING_EXCEPTION;
1330         } else {
1331           return false;
1332         }
1333       }
1334       if( klass == NULL) { sig_is_loaded = false; }
1335     }
1336   }
1337   return sig_is_loaded;
1338 }
1339 
1340 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1341   Handle class_loader(THREAD, m->method_holder()->class_loader());
1342   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1343   ResourceMark rm(THREAD);
1344   Symbol*  signature = m->signature();
1345   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1346     if (ss.type() == T_OBJECT) {
1347       Symbol* name = ss.as_symbol_or_null();
1348       if (name == NULL) return true;
1349       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1350       if (klass == NULL) return true;
1351     }
1352   }
1353   return false;
1354 }
1355 
1356 // Exposed so field engineers can debug VM
1357 void Method::print_short_name(outputStream* st) {
1358   ResourceMark rm;
1359 #ifdef PRODUCT
1360   st->print(" %s::", method_holder()->external_name());
1361 #else
1362   st->print(" %s::", method_holder()->internal_name());
1363 #endif
1364   name()->print_symbol_on(st);
1365   if (WizardMode) signature()->print_symbol_on(st);
1366   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1367     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1368 }
1369 
1370 // Comparer for sorting an object array containing
1371 // Method*s.
1372 static int method_comparator(Method* a, Method* b) {
1373   return a->name()->fast_compare(b->name());
1374 }
1375 
1376 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1377 void Method::sort_methods(Array<Method*>* methods, bool idempotent) {
1378   int length = methods->length();
1379   if (length > 1) {
1380     {
1381       No_Safepoint_Verifier nsv;
1382       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1383     }
1384     // Reset method ordering
1385     for (int i = 0; i < length; i++) {
1386       Method* m = methods->at(i);
1387       m->set_method_idnum(i);
1388     }
1389   }
1390 }
1391 
1392 
1393 //-----------------------------------------------------------------------------------
1394 // Non-product code unless JVM/TI needs it
1395 
1396 #if !defined(PRODUCT) || INCLUDE_JVMTI
1397 class SignatureTypePrinter : public SignatureTypeNames {
1398  private:
1399   outputStream* _st;
1400   bool _use_separator;
1401 
1402   void type_name(const char* name) {
1403     if (_use_separator) _st->print(", ");
1404     _st->print(name);
1405     _use_separator = true;
1406   }
1407 
1408  public:
1409   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1410     _st = st;
1411     _use_separator = false;
1412   }
1413 
1414   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1415   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1416 };
1417 
1418 
1419 void Method::print_name(outputStream* st) {
1420   Thread *thread = Thread::current();
1421   ResourceMark rm(thread);
1422   SignatureTypePrinter sig(signature(), st);
1423   st->print("%s ", is_static() ? "static" : "virtual");
1424   sig.print_returntype();
1425   st->print(" %s.", method_holder()->internal_name());
1426   name()->print_symbol_on(st);
1427   st->print("(");
1428   sig.print_parameters();
1429   st->print(")");
1430 }
1431 #endif // !PRODUCT || INCLUDE_JVMTI
1432 
1433 
1434 //-----------------------------------------------------------------------------------
1435 // Non-product code
1436 
1437 #ifndef PRODUCT
1438 void Method::print_codes_on(outputStream* st) const {
1439   print_codes_on(0, code_size(), st);
1440 }
1441 
1442 void Method::print_codes_on(int from, int to, outputStream* st) const {
1443   Thread *thread = Thread::current();
1444   ResourceMark rm(thread);
1445   methodHandle mh (thread, (Method*)this);
1446   BytecodeStream s(mh);
1447   s.set_interval(from, to);
1448   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1449   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1450 }
1451 #endif // not PRODUCT
1452 
1453 
1454 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1455 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1456 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1457 // as end-of-stream terminator.
1458 
1459 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1460   // bci and line number does not compress into single byte.
1461   // Write out escape character and use regular compression for bci and line number.
1462   write_byte((jubyte)0xFF);
1463   write_signed_int(bci_delta);
1464   write_signed_int(line_delta);
1465 }
1466 
1467 // See comment in method.hpp which explains why this exists.
1468 #if defined(_M_AMD64) && _MSC_VER >= 1400
1469 #pragma optimize("", off)
1470 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1471   write_pair_inline(bci, line);
1472 }
1473 #pragma optimize("", on)
1474 #endif
1475 
1476 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1477   _bci = 0;
1478   _line = 0;
1479 };
1480 
1481 
1482 bool CompressedLineNumberReadStream::read_pair() {
1483   jubyte next = read_byte();
1484   // Check for terminator
1485   if (next == 0) return false;
1486   if (next == 0xFF) {
1487     // Escape character, regular compression used
1488     _bci  += read_signed_int();
1489     _line += read_signed_int();
1490   } else {
1491     // Single byte compression used
1492     _bci  += next >> 3;
1493     _line += next & 0x7;
1494   }
1495   return true;
1496 }
1497 
1498 
1499 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1500   BreakpointInfo* bp = method_holder()->breakpoints();
1501   for (; bp != NULL; bp = bp->next()) {
1502     if (bp->match(this, bci)) {
1503       return bp->orig_bytecode();
1504     }
1505   }
1506   ShouldNotReachHere();
1507   return Bytecodes::_shouldnotreachhere;
1508 }
1509 
1510 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1511   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1512   BreakpointInfo* bp = method_holder()->breakpoints();
1513   for (; bp != NULL; bp = bp->next()) {
1514     if (bp->match(this, bci)) {
1515       bp->set_orig_bytecode(code);
1516       // and continue, in case there is more than one
1517     }
1518   }
1519 }
1520 
1521 void Method::set_breakpoint(int bci) {
1522   InstanceKlass* ik = method_holder();
1523   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1524   bp->set_next(ik->breakpoints());
1525   ik->set_breakpoints(bp);
1526   // do this last:
1527   bp->set(this);
1528 }
1529 
1530 static void clear_matches(Method* m, int bci) {
1531   InstanceKlass* ik = m->method_holder();
1532   BreakpointInfo* prev_bp = NULL;
1533   BreakpointInfo* next_bp;
1534   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1535     next_bp = bp->next();
1536     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1537     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1538       // do this first:
1539       bp->clear(m);
1540       // unhook it
1541       if (prev_bp != NULL)
1542         prev_bp->set_next(next_bp);
1543       else
1544         ik->set_breakpoints(next_bp);
1545       delete bp;
1546       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1547       // at same location. So we have multiple matching (method_index and bci)
1548       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1549       // breakpoint for clear_breakpoint request and keep all other method versions
1550       // BreakpointInfo for future clear_breakpoint request.
1551       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1552       // which is being called when class is unloaded. We delete all the Breakpoint
1553       // information for all versions of method. We may not correctly restore the original
1554       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1555       // so these methods won't be used anymore.
1556       if (bci >= 0) {
1557         break;
1558       }
1559     } else {
1560       // This one is a keeper.
1561       prev_bp = bp;
1562     }
1563   }
1564 }
1565 
1566 void Method::clear_breakpoint(int bci) {
1567   assert(bci >= 0, "");
1568   clear_matches(this, bci);
1569 }
1570 
1571 void Method::clear_all_breakpoints() {
1572   clear_matches(this, -1);
1573 }
1574 
1575 
1576 int Method::invocation_count() {
1577   MethodCounters *mcs = method_counters();
1578   if (TieredCompilation) {
1579     MethodData* const mdo = method_data();
1580     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1581         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1582       return InvocationCounter::count_limit;
1583     } else {
1584       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1585              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1586     }
1587   } else {
1588     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1589   }
1590 }
1591 
1592 int Method::backedge_count() {
1593   MethodCounters *mcs = method_counters();
1594   if (TieredCompilation) {
1595     MethodData* const mdo = method_data();
1596     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1597         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1598       return InvocationCounter::count_limit;
1599     } else {
1600       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1601              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1602     }
1603   } else {
1604     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1605   }
1606 }
1607 
1608 int Method::highest_comp_level() const {
1609   const MethodData* mdo = method_data();
1610   if (mdo != NULL) {
1611     return mdo->highest_comp_level();
1612   } else {
1613     return CompLevel_none;
1614   }
1615 }
1616 
1617 int Method::highest_osr_comp_level() const {
1618   const MethodData* mdo = method_data();
1619   if (mdo != NULL) {
1620     return mdo->highest_osr_comp_level();
1621   } else {
1622     return CompLevel_none;
1623   }
1624 }
1625 
1626 void Method::set_highest_comp_level(int level) {
1627   MethodData* mdo = method_data();
1628   if (mdo != NULL) {
1629     mdo->set_highest_comp_level(level);
1630   }
1631 }
1632 
1633 void Method::set_highest_osr_comp_level(int level) {
1634   MethodData* mdo = method_data();
1635   if (mdo != NULL) {
1636     mdo->set_highest_osr_comp_level(level);
1637   }
1638 }
1639 
1640 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1641   _bci = bci;
1642   _name_index = m->name_index();
1643   _signature_index = m->signature_index();
1644   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1645   if (_orig_bytecode == Bytecodes::_breakpoint)
1646     _orig_bytecode = m->orig_bytecode_at(_bci);
1647   _next = NULL;
1648 }
1649 
1650 void BreakpointInfo::set(Method* method) {
1651 #ifdef ASSERT
1652   {
1653     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1654     if (code == Bytecodes::_breakpoint)
1655       code = method->orig_bytecode_at(_bci);
1656     assert(orig_bytecode() == code, "original bytecode must be the same");
1657   }
1658 #endif
1659   Thread *thread = Thread::current();
1660   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1661   method->incr_number_of_breakpoints(thread);
1662   SystemDictionary::notice_modification();
1663   {
1664     // Deoptimize all dependents on this method
1665     HandleMark hm(thread);
1666     methodHandle mh(thread, method);
1667     Universe::flush_dependents_on_method(mh);
1668   }
1669 }
1670 
1671 void BreakpointInfo::clear(Method* method) {
1672   *method->bcp_from(_bci) = orig_bytecode();
1673   assert(method->number_of_breakpoints() > 0, "must not go negative");
1674   method->decr_number_of_breakpoints(Thread::current());
1675 }
1676 
1677 // jmethodID handling
1678 
1679 // This is a block allocating object, sort of like JNIHandleBlock, only a
1680 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1681 // deleted and so we can do some suboptimal things.
1682 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1683 // never get rid of it.
1684 // It would be nice to be able to parameterize the number of methods for
1685 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1686 // into templates.
1687 
1688 // I feel like this brain dead class should exist somewhere in the STL
1689 
1690 class JNIMethodBlock : public CHeapObj<mtClass> {
1691   enum { number_of_methods = 8 };
1692 
1693   Method*         _methods[number_of_methods];
1694   int             _top;
1695   JNIMethodBlock* _next;
1696  public:
1697   static Method* const _free_method;
1698 
1699   JNIMethodBlock() : _next(NULL), _top(0) {
1700     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1701   }
1702 
1703   Method** add_method(Method* m) {
1704     if (_top < number_of_methods) {
1705       // top points to the next free entry.
1706       int i = _top;
1707       _methods[i] = m;
1708       _top++;
1709       return &_methods[i];
1710     } else if (_top == number_of_methods) {
1711       // if the next free entry ran off the block see if there's a free entry
1712       for (int i = 0; i< number_of_methods; i++) {
1713         if (_methods[i] == _free_method) {
1714           _methods[i] = m;
1715           return &_methods[i];
1716         }
1717       }
1718       // Only check each block once for frees.  They're very unlikely.
1719       // Increment top past the end of the block.
1720       _top++;
1721     }
1722     // need to allocate a next block.
1723     if (_next == NULL) {
1724       _next = new JNIMethodBlock();
1725     }
1726     return _next->add_method(m);
1727   }
1728 
1729   bool contains(Method** m) {
1730     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1731       for (int i = 0; i< number_of_methods; i++) {
1732         if (&(b->_methods[i]) == m) {
1733           return true;
1734         }
1735       }
1736     }
1737     return false;  // not found
1738   }
1739 
1740   // Doesn't really destroy it, just marks it as free so it can be reused.
1741   void destroy_method(Method** m) {
1742 #ifdef ASSERT
1743     assert(contains(m), "should be a methodID");
1744 #endif // ASSERT
1745     *m = _free_method;
1746   }
1747 
1748   // During class unloading the methods are cleared, which is different
1749   // than freed.
1750   void clear_all_methods() {
1751     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1752       for (int i = 0; i< number_of_methods; i++) {
1753         _methods[i] = NULL;
1754       }
1755     }
1756   }
1757 #ifndef PRODUCT
1758   int count_methods() {
1759     // count all allocated methods
1760     int count = 0;
1761     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1762       for (int i = 0; i< number_of_methods; i++) {
1763         if (_methods[i] != _free_method) count++;
1764       }
1765     }
1766     return count;
1767   }
1768 #endif // PRODUCT
1769 };
1770 
1771 // Something that can't be mistaken for an address or a markOop
1772 Method* const JNIMethodBlock::_free_method = (Method*)55;
1773 
1774 // Add a method id to the jmethod_ids
1775 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1776   ClassLoaderData* cld = loader_data;
1777 
1778   if (!SafepointSynchronize::is_at_safepoint()) {
1779     // Have to add jmethod_ids() to class loader data thread-safely.
1780     // Also have to add the method to the list safely, which the cld lock
1781     // protects as well.
1782     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1783     if (cld->jmethod_ids() == NULL) {
1784       cld->set_jmethod_ids(new JNIMethodBlock());
1785     }
1786     // jmethodID is a pointer to Method*
1787     return (jmethodID)cld->jmethod_ids()->add_method(m);
1788   } else {
1789     // At safepoint, we are single threaded and can set this.
1790     if (cld->jmethod_ids() == NULL) {
1791       cld->set_jmethod_ids(new JNIMethodBlock());
1792     }
1793     // jmethodID is a pointer to Method*
1794     return (jmethodID)cld->jmethod_ids()->add_method(m);
1795   }
1796 }
1797 
1798 // Mark a jmethodID as free.  This is called when there is a data race in
1799 // InstanceKlass while creating the jmethodID cache.
1800 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1801   ClassLoaderData* cld = loader_data;
1802   Method** ptr = (Method**)m;
1803   assert(cld->jmethod_ids() != NULL, "should have method handles");
1804   cld->jmethod_ids()->destroy_method(ptr);
1805 }
1806 
1807 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1808   // Can't assert the method_holder is the same because the new method has the
1809   // scratch method holder.
1810   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1811            == new_method->method_holder()->class_loader(),
1812          "changing to a different class loader");
1813   // Just change the method in place, jmethodID pointer doesn't change.
1814   *((Method**)jmid) = new_method;
1815 }
1816 
1817 bool Method::is_method_id(jmethodID mid) {
1818   Method* m = resolve_jmethod_id(mid);
1819   assert(m != NULL, "should be called with non-null method");
1820   InstanceKlass* ik = m->method_holder();
1821   ClassLoaderData* cld = ik->class_loader_data();
1822   if (cld->jmethod_ids() == NULL) return false;
1823   return (cld->jmethod_ids()->contains((Method**)mid));
1824 }
1825 
1826 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1827   if (mid == NULL) return NULL;
1828   Method* o = resolve_jmethod_id(mid);
1829   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1830     return NULL;
1831   }
1832   return o;
1833 };
1834 
1835 void Method::set_on_stack(const bool value) {
1836   // Set both the method itself and its constant pool.  The constant pool
1837   // on stack means some method referring to it is also on the stack.
1838   _access_flags.set_on_stack(value);
1839   constants()->set_on_stack(value);
1840   if (value) MetadataOnStackMark::record(this);
1841 }
1842 
1843 // Called when the class loader is unloaded to make all methods weak.
1844 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1845   loader_data->jmethod_ids()->clear_all_methods();
1846 }
1847 
1848 
1849 // Check that this pointer is valid by checking that the vtbl pointer matches
1850 bool Method::is_valid_method() const {
1851   if (this == NULL) {
1852     return false;
1853   } else if (!is_metaspace_object()) {
1854     return false;
1855   } else {
1856     Method m;
1857     // This assumes that the vtbl pointer is the first word of a C++ object.
1858     // This assumption is also in universe.cpp patch_klass_vtble
1859     void* vtbl2 = dereference_vptr((void*)&m);
1860     void* this_vtbl = dereference_vptr((void*)this);
1861     return vtbl2 == this_vtbl;
1862   }
1863 }
1864 
1865 #ifndef PRODUCT
1866 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1867   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1868 }
1869 #endif // PRODUCT
1870 
1871 
1872 // Printing
1873 
1874 #ifndef PRODUCT
1875 
1876 void Method::print_on(outputStream* st) const {
1877   ResourceMark rm;
1878   assert(is_method(), "must be method");
1879   st->print_cr(internal_name());
1880   // get the effect of PrintOopAddress, always, for methods:
1881   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1882   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1883   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1884   constants()->print_value_on(st); st->cr();
1885   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1886   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1887   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1888   st->print_cr(" - max stack:         %d",   max_stack());
1889   st->print_cr(" - max locals:        %d",   max_locals());
1890   st->print_cr(" - size of params:    %d",   size_of_parameters());
1891   st->print_cr(" - method size:       %d",   method_size());
1892   if (intrinsic_id() != vmIntrinsics::_none)
1893     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1894   if (highest_comp_level() != CompLevel_none)
1895     st->print_cr(" - highest level:     %d", highest_comp_level());
1896   st->print_cr(" - vtable index:      %d",   _vtable_index);
1897   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1898   st->print(   " - adapters:          ");
1899   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1900   if (a == NULL)
1901     st->print_cr(INTPTR_FORMAT, a);
1902   else
1903     a->print_adapter_on(st);
1904   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1905   st->print_cr(" - code size:         %d",   code_size());
1906   if (code_size() != 0) {
1907     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1908     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1909   }
1910   if (method_data() != NULL) {
1911     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1912   }
1913   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1914   if (checked_exceptions_length() > 0) {
1915     CheckedExceptionElement* table = checked_exceptions_start();
1916     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1917     if (Verbose) {
1918       for (int i = 0; i < checked_exceptions_length(); i++) {
1919         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1920       }
1921     }
1922   }
1923   if (has_linenumber_table()) {
1924     u_char* table = compressed_linenumber_table();
1925     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1926     if (Verbose) {
1927       CompressedLineNumberReadStream stream(table);
1928       while (stream.read_pair()) {
1929         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1930       }
1931     }
1932   }
1933   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1934   if (localvariable_table_length() > 0) {
1935     LocalVariableTableElement* table = localvariable_table_start();
1936     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1937     if (Verbose) {
1938       for (int i = 0; i < localvariable_table_length(); i++) {
1939         int bci = table[i].start_bci;
1940         int len = table[i].length;
1941         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1942         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
1943         int slot = table[i].slot;
1944         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
1945       }
1946     }
1947   }
1948   if (code() != NULL) {
1949     st->print   (" - compiled code: ");
1950     code()->print_value_on(st);
1951   }
1952   if (is_native()) {
1953     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
1954     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
1955   }
1956 }
1957 
1958 #endif //PRODUCT
1959 
1960 void Method::print_value_on(outputStream* st) const {
1961   assert(is_method(), "must be method");
1962   st->print_cr(internal_name());
1963   print_address_on(st);
1964   st->print(" ");
1965   name()->print_value_on(st);
1966   st->print(" ");
1967   signature()->print_value_on(st);
1968   st->print(" in ");
1969   method_holder()->print_value_on(st);
1970   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
1971   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
1972 }
1973 
1974 #if INCLUDE_SERVICES
1975 // Size Statistics
1976 void Method::collect_statistics(KlassSizeStats *sz) const {
1977   int mysize = sz->count(this);
1978   sz->_method_bytes += mysize;
1979   sz->_method_all_bytes += mysize;
1980   sz->_rw_bytes += mysize;
1981 
1982   if (constMethod()) {
1983     constMethod()->collect_statistics(sz);
1984   }
1985   if (method_data()) {
1986     method_data()->collect_statistics(sz);
1987   }
1988 }
1989 #endif // INCLUDE_SERVICES
1990 
1991 // Verification
1992 
1993 void Method::verify_on(outputStream* st) {
1994   guarantee(is_method(), "object must be method");
1995   guarantee(constants()->is_constantPool(), "should be constant pool");
1996   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
1997   MethodData* md = method_data();
1998   guarantee(md == NULL ||
1999       md->is_methodData(), "should be method data");
2000 }