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