1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #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/orderAccess.inline.hpp"
  53 #include "runtime/relocator.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "utilities/quickSort.hpp"
  57 #include "utilities/xmlstream.hpp"
  58 
  59 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  60 
  61 // Implementation of Method
  62 
  63 Method* Method::allocate(ClassLoaderData* loader_data,
  64                          int byte_code_size,
  65                          AccessFlags access_flags,
  66                          InlineTableSizes* sizes,
  67                          ConstMethod::MethodType method_type,
  68                          TRAPS) {
  69   assert(!access_flags.is_native() || byte_code_size == 0,
  70          "native methods should not contain byte codes");
  71   ConstMethod* cm = ConstMethod::allocate(loader_data,
  72                                           byte_code_size,
  73                                           sizes,
  74                                           method_type,
  75                                           CHECK_NULL);
  76 
  77   int size = Method::size(access_flags.is_native());
  78 
  79   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  80 }
  81 
  82 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  83   No_Safepoint_Verifier no_safepoint;
  84   set_constMethod(xconst);
  85   set_access_flags(access_flags);
  86   set_method_size(size);
  87 #ifdef CC_INTERP
  88   set_result_index(T_VOID);
  89 #endif
  90   set_intrinsic_id(vmIntrinsics::_none);
  91   set_jfr_towrite(false);
  92   set_force_inline(false);
  93   set_hidden(false);
  94   set_dont_inline(false);
  95   set_method_data(NULL);
  96   set_method_counters(NULL);
  97   set_vtable_index(Method::garbage_vtable_index);
  98 
  99   // Fix and bury in Method*
 100   set_interpreter_entry(NULL); // sets i2i entry and from_int
 101   set_adapter_entry(NULL);
 102   clear_code(); // from_c/from_i get set to c2i/i2i
 103 
 104   if (access_flags.is_native()) {
 105     clear_native_function();
 106     set_signature_handler(NULL);
 107   }
 108 
 109   NOT_PRODUCT(set_compiled_invocation_count(0);)
 110 }
 111 
 112 // Release Method*.  The nmethod will be gone when we get here because
 113 // we've walked the code cache.
 114 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 115   MetadataFactory::free_metadata(loader_data, constMethod());
 116   set_constMethod(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_data());
 118   set_method_data(NULL);
 119   MetadataFactory::free_metadata(loader_data, method_counters());
 120   set_method_counters(NULL);
 121   // The nmethod will be gone when we get here.
 122   if (code() != NULL) _code = NULL;
 123 }
 124 
 125 address Method::get_i2c_entry() {
 126   assert(_adapter != NULL, "must have");
 127   return _adapter->get_i2c_entry();
 128 }
 129 
 130 address Method::get_c2i_entry() {
 131   assert(_adapter != NULL, "must have");
 132   return _adapter->get_c2i_entry();
 133 }
 134 
 135 address Method::get_c2i_unverified_entry() {
 136   assert(_adapter != NULL, "must have");
 137   return _adapter->get_c2i_unverified_entry();
 138 }
 139 
 140 char* Method::name_and_sig_as_C_string() const {
 141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 149   const char* klass_name = klass->external_name();
 150   int klass_name_len  = (int)strlen(klass_name);
 151   int method_name_len = method_name->utf8_length();
 152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 154   strcpy(dest, klass_name);
 155   dest[klass_name_len] = '.';
 156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 158   dest[len] = 0;
 159   return dest;
 160 }
 161 
 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 163   Symbol* klass_name = klass->name();
 164   klass_name->as_klass_external_name(buf, size);
 165   int len = (int)strlen(buf);
 166 
 167   if (len < size - 1) {
 168     buf[len++] = '.';
 169 
 170     method_name->as_C_string(&(buf[len]), size - len);
 171     len = (int)strlen(buf);
 172 
 173     signature->as_C_string(&(buf[len]), size - len);
 174   }
 175 
 176   return buf;
 177 }
 178 
 179 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 181   // access exception table
 182   ExceptionTable table(mh());
 183   int length = table.length();
 184   // iterate through all entries sequentially
 185   constantPoolHandle pool(THREAD, mh->constants());
 186   for (int i = 0; i < length; i ++) {
 187     //reacquire the table in case a GC happened
 188     ExceptionTable table(mh());
 189     int beg_bci = table.start_pc(i);
 190     int end_bci = table.end_pc(i);
 191     assert(beg_bci <= end_bci, "inconsistent exception table");
 192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 193       // exception handler bci range covers throw_bci => investigate further
 194       int handler_bci = table.handler_pc(i);
 195       int klass_index = table.catch_type_index(i);
 196       if (klass_index == 0) {
 197         return handler_bci;
 198       } else if (ex_klass.is_null()) {
 199         return handler_bci;
 200       } else {
 201         // we know the exception class => get the constraint class
 202         // this may require loading of the constraint class; if verification
 203         // fails or some other exception occurs, return handler_bci
 204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 205         KlassHandle klass = KlassHandle(THREAD, k);
 206         assert(klass.not_null(), "klass not loaded");
 207         if (ex_klass->is_subtype_of(klass())) {
 208           return handler_bci;
 209         }
 210       }
 211     }
 212   }
 213 
 214   return -1;
 215 }
 216 
 217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 218 
 219   Thread* myThread    = Thread::current();
 220   methodHandle h_this(myThread, this);
 221 #ifdef ASSERT
 222   bool has_capability = myThread->is_VM_thread() ||
 223                         myThread->is_ConcurrentGC_thread() ||
 224                         myThread->is_GC_task_thread();
 225 
 226   if (!has_capability) {
 227     if (!VerifyStack && !VerifyLastFrame) {
 228       // verify stack calls this outside VM thread
 229       warning("oopmap should only be accessed by the "
 230               "VM, GC task or CMS threads (or during debugging)");
 231       InterpreterOopMap local_mask;
 232       method_holder()->mask_for(h_this, bci, &local_mask);
 233       local_mask.print();
 234     }
 235   }
 236 #endif
 237   method_holder()->mask_for(h_this, bci, mask);
 238   return;
 239 }
 240 
 241 
 242 int Method::bci_from(address bcp) const {
 243 #ifdef ASSERT
 244   { ResourceMark rm;
 245   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 246          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 247   }
 248 #endif
 249   return bcp - code_base();
 250 }
 251 
 252 
 253 // Return (int)bcx if it appears to be a valid BCI.
 254 // Return bci_from((address)bcx) if it appears to be a valid BCP.
 255 // Return -1 otherwise.
 256 // Used by profiling code, when invalid data is a possibility.
 257 // The caller is responsible for validating the Method* itself.
 258 int Method::validate_bci_from_bcx(intptr_t bcx) const {
 259   // keep bci as -1 if not a valid bci
 260   int bci = -1;
 261   if (bcx == 0 || (address)bcx == code_base()) {
 262     // code_size() may return 0 and we allow 0 here
 263     // the method may be native
 264     bci = 0;
 265   } else if (frame::is_bci(bcx)) {
 266     if (bcx < code_size()) {
 267       bci = (int)bcx;
 268     }
 269   } else if (contains((address)bcx)) {
 270     bci = (address)bcx - code_base();
 271   }
 272   // Assert that if we have dodged any asserts, bci is negative.
 273   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 274   return bci;
 275 }
 276 
 277 address Method::bcp_from(int bci) const {
 278   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), err_msg("illegal bci: %d", bci));
 279   address bcp = code_base() + bci;
 280   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 281   return bcp;
 282 }
 283 
 284 
 285 int Method::size(bool is_native) {
 286   // If native, then include pointers for native_function and signature_handler
 287   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 288   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 289   return align_object_size(header_size() + extra_words);
 290 }
 291 
 292 
 293 Symbol* Method::klass_name() const {
 294   Klass* k = method_holder();
 295   assert(k->is_klass(), "must be klass");
 296   InstanceKlass* ik = (InstanceKlass*) k;
 297   return ik->name();
 298 }
 299 
 300 
 301 // Attempt to return method oop to original state.  Clear any pointers
 302 // (to objects outside the shared spaces).  We won't be able to predict
 303 // where they should point in a new JVM.  Further initialize some
 304 // entries now in order allow them to be write protected later.
 305 
 306 void Method::remove_unshareable_info() {
 307   unlink_method();
 308 }
 309 
 310 
 311 bool Method::was_executed_more_than(int n) {
 312   // Invocation counter is reset when the Method* is compiled.
 313   // If the method has compiled code we therefore assume it has
 314   // be excuted more than n times.
 315   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 316     // interpreter doesn't bump invocation counter of trivial methods
 317     // compiler does not bump invocation counter of compiled methods
 318     return true;
 319   }
 320   else if ((method_counters() != NULL &&
 321             method_counters()->invocation_counter()->carry()) ||
 322            (method_data() != NULL &&
 323             method_data()->invocation_counter()->carry())) {
 324     // The carry bit is set when the counter overflows and causes
 325     // a compilation to occur.  We don't know how many times
 326     // the counter has been reset, so we simply assume it has
 327     // been executed more than n times.
 328     return true;
 329   } else {
 330     return invocation_count() > n;
 331   }
 332 }
 333 
 334 void Method::print_invocation_count() {
 335   if (is_static()) tty->print("static ");
 336   if (is_final()) tty->print("final ");
 337   if (is_synchronized()) tty->print("synchronized ");
 338   if (is_native()) tty->print("native ");
 339   tty->print("%s::", method_holder()->external_name());
 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 #ifndef PRODUCT
 353   if (CountCompiledCalls) {
 354     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 355   }
 356 #endif
 357 }
 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 bool Method::is_final_method(AccessFlags class_access_flags) const {
 513   // or "does_not_require_vtable_entry"
 514   // default method or overpass can occur, is not final (reuses vtable entry)
 515   // private methods get vtable entries for backward class compatibility.
 516   if (is_overpass() || is_default_method())  return false;
 517   return is_final() || class_access_flags.is_final();
 518 }
 519 
 520 bool Method::is_final_method() const {
 521   return is_final_method(method_holder()->access_flags());
 522 }
 523 
 524 bool Method::is_default_method() const {
 525   if (method_holder() != NULL &&
 526       method_holder()->is_interface() &&
 527       !is_abstract()) {
 528     return true;
 529   } else {
 530     return false;
 531   }
 532 }
 533 
 534 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 535   if (is_final_method(class_access_flags))  return true;
 536 #ifdef ASSERT
 537   ResourceMark rm;
 538   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 539   if (class_access_flags.is_interface()) {
 540       assert(is_nonv == is_static(), err_msg("is_nonv=%s", name_and_sig_as_C_string()));
 541   }
 542 #endif
 543   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 544   return vtable_index() == nonvirtual_vtable_index;
 545 }
 546 
 547 bool Method::can_be_statically_bound() const {
 548   return can_be_statically_bound(method_holder()->access_flags());
 549 }
 550 
 551 bool Method::is_accessor() const {
 552   if (code_size() != 5) return false;
 553   if (size_of_parameters() != 1) return false;
 554   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 555   if (java_code_at(1) != Bytecodes::_getfield) return false;
 556   if (java_code_at(4) != Bytecodes::_areturn &&
 557       java_code_at(4) != Bytecodes::_ireturn ) return false;
 558   return true;
 559 }
 560 
 561 
 562 bool Method::is_initializer() const {
 563   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 564 }
 565 
 566 bool Method::has_valid_initializer_flags() const {
 567   return (is_static() ||
 568           method_holder()->major_version() < 51);
 569 }
 570 
 571 bool Method::is_static_initializer() const {
 572   // For classfiles version 51 or greater, ensure that the clinit method is
 573   // static.  Non-static methods with the name "<clinit>" are not static
 574   // initializers. (older classfiles exempted for backward compatibility)
 575   return name() == vmSymbols::class_initializer_name() &&
 576          has_valid_initializer_flags();
 577 }
 578 
 579 
 580 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 581   int length = method->checked_exceptions_length();
 582   if (length == 0) {  // common case
 583     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 584   } else {
 585     methodHandle h_this(THREAD, method);
 586     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 587     objArrayHandle mirrors (THREAD, m_oop);
 588     for (int i = 0; i < length; i++) {
 589       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 590       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 591       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 592       mirrors->obj_at_put(i, k->java_mirror());
 593     }
 594     return mirrors;
 595   }
 596 };
 597 
 598 
 599 int Method::line_number_from_bci(int bci) const {
 600   if (bci == SynchronizationEntryBCI) bci = 0;
 601   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 602   int best_bci  =  0;
 603   int best_line = -1;
 604 
 605   if (has_linenumber_table()) {
 606     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 607     // Not necessarily sorted and not necessarily one-to-one.
 608     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 609     while (stream.read_pair()) {
 610       if (stream.bci() == bci) {
 611         // perfect match
 612         return stream.line();
 613       } else {
 614         // update best_bci/line
 615         if (stream.bci() < bci && stream.bci() >= best_bci) {
 616           best_bci  = stream.bci();
 617           best_line = stream.line();
 618         }
 619       }
 620     }
 621   }
 622   return best_line;
 623 }
 624 
 625 
 626 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 627   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 628     Thread *thread = Thread::current();
 629     Symbol* klass_name = constants()->klass_name_at(klass_index);
 630     Handle loader(thread, method_holder()->class_loader());
 631     Handle prot  (thread, method_holder()->protection_domain());
 632     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 633   } else {
 634     return true;
 635   }
 636 }
 637 
 638 
 639 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 640   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 641   if (must_be_resolved) {
 642     // Make sure klass is resolved in constantpool.
 643     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 644   }
 645   return is_klass_loaded_by_klass_index(klass_index);
 646 }
 647 
 648 
 649 void Method::set_native_function(address function, bool post_event_flag) {
 650   assert(function != NULL, "use clear_native_function to unregister natives");
 651   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 652   address* native_function = native_function_addr();
 653 
 654   // We can see racers trying to place the same native function into place. Once
 655   // is plenty.
 656   address current = *native_function;
 657   if (current == function) return;
 658   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 659       function != NULL) {
 660     // native_method_throw_unsatisfied_link_error_entry() should only
 661     // be passed when post_event_flag is false.
 662     assert(function !=
 663       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 664       "post_event_flag mis-match");
 665 
 666     // post the bind event, and possible change the bind function
 667     JvmtiExport::post_native_method_bind(this, &function);
 668   }
 669   *native_function = function;
 670   // This function can be called more than once. We must make sure that we always
 671   // use the latest registered method -> check if a stub already has been generated.
 672   // If so, we have to make it not_entrant.
 673   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 674   if (nm != NULL) {
 675     nm->make_not_entrant();
 676   }
 677 }
 678 
 679 
 680 bool Method::has_native_function() const {
 681   if (is_method_handle_intrinsic())
 682     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 683   address func = native_function();
 684   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 685 }
 686 
 687 
 688 void Method::clear_native_function() {
 689   // Note: is_method_handle_intrinsic() is allowed here.
 690   set_native_function(
 691     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 692     !native_bind_event_is_interesting);
 693   clear_code();
 694 }
 695 
 696 address Method::critical_native_function() {
 697   methodHandle mh(this);
 698   return NativeLookup::lookup_critical_entry(mh);
 699 }
 700 
 701 
 702 void Method::set_signature_handler(address handler) {
 703   address* signature_handler =  signature_handler_addr();
 704   *signature_handler = handler;
 705 }
 706 
 707 
 708 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 709   if (PrintCompilation && report) {
 710     ttyLocker ttyl;
 711     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 712     if (comp_level == CompLevel_all) {
 713       tty->print("all levels ");
 714     } else {
 715       tty->print("levels ");
 716       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 717         tty->print("%d ", i);
 718       }
 719     }
 720     this->print_short_name(tty);
 721     int size = this->code_size();
 722     if (size > 0) {
 723       tty->print(" (%d bytes)", size);
 724     }
 725     if (reason != NULL) {
 726       tty->print("   %s", reason);
 727     }
 728     tty->cr();
 729   }
 730   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 731     ttyLocker ttyl;
 732     xtty->begin_elem("make_not_%scompilable thread='" UINTX_FORMAT "'",
 733                      is_osr ? "osr_" : "", os::current_thread_id());
 734     if (reason != NULL) {
 735       xtty->print(" reason=\'%s\'", reason);
 736     }
 737     xtty->method(this);
 738     xtty->stamp();
 739     xtty->end_elem();
 740   }
 741 }
 742 
 743 bool Method::is_always_compilable() const {
 744   // Generated adapters must be compiled
 745   if (is_method_handle_intrinsic() && is_synthetic()) {
 746     assert(!is_not_c1_compilable(), "sanity check");
 747     assert(!is_not_c2_compilable(), "sanity check");
 748     return true;
 749   }
 750 
 751   return false;
 752 }
 753 
 754 bool Method::is_not_compilable(int comp_level) const {
 755   if (number_of_breakpoints() > 0)
 756     return true;
 757   if (is_always_compilable())
 758     return false;
 759   if (comp_level == CompLevel_any)
 760     return is_not_c1_compilable() || is_not_c2_compilable();
 761   if (is_c1_compile(comp_level))
 762     return is_not_c1_compilable();
 763   if (is_c2_compile(comp_level))
 764     return is_not_c2_compilable();
 765   return false;
 766 }
 767 
 768 // call this when compiler finds that this method is not compilable
 769 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 770   if (is_always_compilable()) {
 771     // Don't mark a method which should be always compilable
 772     return;
 773   }
 774   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 775   if (comp_level == CompLevel_all) {
 776     set_not_c1_compilable();
 777     set_not_c2_compilable();
 778   } else {
 779     if (is_c1_compile(comp_level))
 780       set_not_c1_compilable();
 781     if (is_c2_compile(comp_level))
 782       set_not_c2_compilable();
 783   }
 784   CompilationPolicy::policy()->disable_compilation(this);
 785   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 786 }
 787 
 788 bool Method::is_not_osr_compilable(int comp_level) const {
 789   if (is_not_compilable(comp_level))
 790     return true;
 791   if (comp_level == CompLevel_any)
 792     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 793   if (is_c1_compile(comp_level))
 794     return is_not_c1_osr_compilable();
 795   if (is_c2_compile(comp_level))
 796     return is_not_c2_osr_compilable();
 797   return false;
 798 }
 799 
 800 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 801   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 802   if (comp_level == CompLevel_all) {
 803     set_not_c1_osr_compilable();
 804     set_not_c2_osr_compilable();
 805   } else {
 806     if (is_c1_compile(comp_level))
 807       set_not_c1_osr_compilable();
 808     if (is_c2_compile(comp_level))
 809       set_not_c2_osr_compilable();
 810   }
 811   CompilationPolicy::policy()->disable_compilation(this);
 812   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 813 }
 814 
 815 // Revert to using the interpreter and clear out the nmethod
 816 void Method::clear_code() {
 817 
 818   // this may be NULL if c2i adapters have not been made yet
 819   // Only should happen at allocate time.
 820   if (_adapter == NULL) {
 821     _from_compiled_entry    = NULL;
 822   } else {
 823     _from_compiled_entry    = _adapter->get_c2i_entry();
 824   }
 825   OrderAccess::storestore();
 826   _from_interpreted_entry = _i2i_entry;
 827   OrderAccess::storestore();
 828   _code = NULL;
 829 }
 830 
 831 // Called by class data sharing to remove any entry points (which are not shared)
 832 void Method::unlink_method() {
 833   _code = NULL;
 834   _i2i_entry = NULL;
 835   _from_interpreted_entry = NULL;
 836   if (is_native()) {
 837     *native_function_addr() = NULL;
 838     set_signature_handler(NULL);
 839   }
 840   NOT_PRODUCT(set_compiled_invocation_count(0);)
 841   _adapter = NULL;
 842   _from_compiled_entry = NULL;
 843 
 844   // In case of DumpSharedSpaces, _method_data should always be NULL.
 845   //
 846   // During runtime (!DumpSharedSpaces), when we are cleaning a
 847   // shared class that failed to load, this->link_method() may
 848   // have already been called (before an exception happened), so
 849   // this->_method_data may not be NULL.
 850   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 851 
 852   set_method_data(NULL);
 853   set_method_counters(NULL);
 854 }
 855 
 856 // Called when the method_holder is getting linked. Setup entrypoints so the method
 857 // is ready to be called from interpreter, compiler, and vtables.
 858 void Method::link_method(methodHandle h_method, TRAPS) {
 859   // If the code cache is full, we may reenter this function for the
 860   // leftover methods that weren't linked.
 861   if (_i2i_entry != NULL) return;
 862 
 863   assert(_adapter == NULL, "init'd to NULL" );
 864   assert( _code == NULL, "nothing compiled yet" );
 865 
 866   // Setup interpreter entrypoint
 867   assert(this == h_method(), "wrong h_method()" );
 868   address entry = Interpreter::entry_for_method(h_method);
 869   assert(entry != NULL, "interpreter entry must be non-null");
 870   // Sets both _i2i_entry and _from_interpreted_entry
 871   set_interpreter_entry(entry);
 872 
 873   // Don't overwrite already registered native entries.
 874   if (is_native() && !has_native_function()) {
 875     set_native_function(
 876       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 877       !native_bind_event_is_interesting);
 878   }
 879 
 880   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 881   // special handling of vtables.  An alternative is to make adapters more
 882   // lazily by calling make_adapter() from from_compiled_entry() for the
 883   // normal calls.  For vtable calls life gets more complicated.  When a
 884   // call-site goes mega-morphic we need adapters in all methods which can be
 885   // called from the vtable.  We need adapters on such methods that get loaded
 886   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 887   // problem we'll make these lazily later.
 888   (void) make_adapters(h_method, CHECK);
 889 
 890   // ONLY USE the h_method now as make_adapter may have blocked
 891 
 892 }
 893 
 894 address Method::make_adapters(methodHandle mh, TRAPS) {
 895   // Adapters for compiled code are made eagerly here.  They are fairly
 896   // small (generally < 100 bytes) and quick to make (and cached and shared)
 897   // so making them eagerly shouldn't be too expensive.
 898   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 899   if (adapter == NULL ) {
 900     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 901   }
 902 
 903   mh->set_adapter_entry(adapter);
 904   mh->_from_compiled_entry = adapter->get_c2i_entry();
 905   return adapter->get_c2i_entry();
 906 }
 907 
 908 void Method::restore_unshareable_info(TRAPS) {
 909   // Since restore_unshareable_info can be called more than once for a method, don't
 910   // redo any work.   If this field is restored, there is nothing to do.
 911   if (_from_compiled_entry == NULL) {
 912     // restore method's vtable by calling a virtual function
 913     restore_vtable();
 914 
 915     methodHandle mh(THREAD, this);
 916     link_method(mh, CHECK);
 917   }
 918 }
 919 
 920 
 921 // The verified_code_entry() must be called when a invoke is resolved
 922 // on this method.
 923 
 924 // It returns the compiled code entry point, after asserting not null.
 925 // This function is called after potential safepoints so that nmethod
 926 // or adapter that it points to is still live and valid.
 927 // This function must not hit a safepoint!
 928 address Method::verified_code_entry() {
 929   debug_only(No_Safepoint_Verifier nsv;)
 930   assert(_from_compiled_entry != NULL, "must be set");
 931   return _from_compiled_entry;
 932 }
 933 
 934 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 935 // (could be racing a deopt).
 936 // Not inline to avoid circular ref.
 937 bool Method::check_code() const {
 938   // cached in a register or local.  There's a race on the value of the field.
 939   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 940   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 941 }
 942 
 943 // Install compiled code.  Instantly it can execute.
 944 void Method::set_code(methodHandle mh, nmethod *code) {
 945   assert( code, "use clear_code to remove code" );
 946   assert( mh->check_code(), "" );
 947 
 948   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 949 
 950   // These writes must happen in this order, because the interpreter will
 951   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 952   // which jumps to _from_compiled_entry.
 953   mh->_code = code;             // Assign before allowing compiled code to exec
 954 
 955   int comp_level = code->comp_level();
 956   // In theory there could be a race here. In practice it is unlikely
 957   // and not worth worrying about.
 958   if (comp_level > mh->highest_comp_level()) {
 959     mh->set_highest_comp_level(comp_level);
 960   }
 961 
 962   OrderAccess::storestore();
 963 #ifdef SHARK
 964   mh->_from_interpreted_entry = code->insts_begin();
 965 #else //!SHARK
 966   mh->_from_compiled_entry = code->verified_entry_point();
 967   OrderAccess::storestore();
 968   // Instantly compiled code can execute.
 969   if (!mh->is_method_handle_intrinsic())
 970     mh->_from_interpreted_entry = mh->get_i2c_entry();
 971 #endif //!SHARK
 972 }
 973 
 974 
 975 bool Method::is_overridden_in(Klass* k) const {
 976   InstanceKlass* ik = InstanceKlass::cast(k);
 977 
 978   if (ik->is_interface()) return false;
 979 
 980   // If method is an interface, we skip it - except if it
 981   // is a miranda method
 982   if (method_holder()->is_interface()) {
 983     // Check that method is not a miranda method
 984     if (ik->lookup_method(name(), signature()) == NULL) {
 985       // No implementation exist - so miranda method
 986       return false;
 987     }
 988     return true;
 989   }
 990 
 991   assert(ik->is_subclass_of(method_holder()), "should be subklass");
 992   assert(ik->vtable() != NULL, "vtable should exist");
 993   if (!has_vtable_index()) {
 994     return false;
 995   } else {
 996     Method* vt_m = ik->method_at_vtable(vtable_index());
 997     return vt_m != this;
 998   }
 999 }
1000 
1001 
1002 // give advice about whether this Method* should be cached or not
1003 bool Method::should_not_be_cached() const {
1004   if (is_old()) {
1005     // This method has been redefined. It is either EMCP or obsolete
1006     // and we don't want to cache it because that would pin the method
1007     // down and prevent it from being collectible if and when it
1008     // finishes executing.
1009     return true;
1010   }
1011 
1012   // caching this method should be just fine
1013   return false;
1014 }
1015 
1016 
1017 /**
1018  *  Returns true if this is one of the specially treated methods for
1019  *  security related stack walks (like Reflection.getCallerClass).
1020  */
1021 bool Method::is_ignored_by_security_stack_walk() const {
1022   if (intrinsic_id() == vmIntrinsics::_invoke) {
1023     // This is Method.invoke() -- ignore it
1024     return true;
1025   }
1026   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1027     // This is an auxilary frame -- ignore it
1028     return true;
1029   }
1030   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1031     // This is an internal adapter frame for method handles -- ignore it
1032     return true;
1033   }
1034   return false;
1035 }
1036 
1037 
1038 // Constant pool structure for invoke methods:
1039 enum {
1040   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1041   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1042   _imcp_limit
1043 };
1044 
1045 // Test if this method is an MH adapter frame generated by Java code.
1046 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1047 bool Method::is_compiled_lambda_form() const {
1048   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1049 }
1050 
1051 // Test if this method is an internal MH primitive method.
1052 bool Method::is_method_handle_intrinsic() const {
1053   vmIntrinsics::ID iid = intrinsic_id();
1054   return (MethodHandles::is_signature_polymorphic(iid) &&
1055           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1056 }
1057 
1058 bool Method::has_member_arg() const {
1059   vmIntrinsics::ID iid = intrinsic_id();
1060   return (MethodHandles::is_signature_polymorphic(iid) &&
1061           MethodHandles::has_member_arg(iid));
1062 }
1063 
1064 // Make an instance of a signature-polymorphic internal MH primitive.
1065 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1066                                                          Symbol* signature,
1067                                                          TRAPS) {
1068   ResourceMark rm;
1069   methodHandle empty;
1070 
1071   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1072   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1073   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1074   if (TraceMethodHandles) {
1075     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1076   }
1077 
1078   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1079   name->increment_refcount();
1080   signature->increment_refcount();
1081 
1082   int cp_length = _imcp_limit;
1083   ClassLoaderData* loader_data = holder->class_loader_data();
1084   constantPoolHandle cp;
1085   {
1086     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1087     cp = constantPoolHandle(THREAD, cp_oop);
1088   }
1089   cp->set_pool_holder(InstanceKlass::cast(holder()));
1090   cp->symbol_at_put(_imcp_invoke_name,       name);
1091   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1092   cp->set_has_preresolution();
1093 
1094   // decide on access bits:  public or not?
1095   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1096   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1097   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1098   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1099 
1100   methodHandle m;
1101   {
1102     InlineTableSizes sizes;
1103     Method* m_oop = Method::allocate(loader_data, 0,
1104                                      accessFlags_from(flags_bits), &sizes,
1105                                      ConstMethod::NORMAL, CHECK_(empty));
1106     m = methodHandle(THREAD, m_oop);
1107   }
1108   m->set_constants(cp());
1109   m->set_name_index(_imcp_invoke_name);
1110   m->set_signature_index(_imcp_invoke_signature);
1111   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1112   assert(m->signature() == signature, "");
1113 #ifdef CC_INTERP
1114   ResultTypeFinder rtf(signature);
1115   m->set_result_index(rtf.type());
1116 #endif
1117   m->compute_size_of_parameters(THREAD);
1118   m->init_intrinsic_id();
1119   assert(m->is_method_handle_intrinsic(), "");
1120 #ifdef ASSERT
1121   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1122   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1123   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1124 #endif //ASSERT
1125 
1126   // Finally, set up its entry points.
1127   assert(m->can_be_statically_bound(), "");
1128   m->set_vtable_index(Method::nonvirtual_vtable_index);
1129   m->link_method(m, CHECK_(empty));
1130 
1131   if (TraceMethodHandles && (Verbose || WizardMode))
1132     m->print_on(tty);
1133 
1134   return m;
1135 }
1136 
1137 Klass* Method::check_non_bcp_klass(Klass* klass) {
1138   if (klass != NULL && klass->class_loader() != NULL) {
1139     if (klass->oop_is_objArray())
1140       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1141     return klass;
1142   }
1143   return NULL;
1144 }
1145 
1146 
1147 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1148                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1149   // Code below does not work for native methods - they should never get rewritten anyway
1150   assert(!m->is_native(), "cannot rewrite native methods");
1151   // Allocate new Method*
1152   AccessFlags flags = m->access_flags();
1153 
1154   ConstMethod* cm = m->constMethod();
1155   int checked_exceptions_len = cm->checked_exceptions_length();
1156   int localvariable_len = cm->localvariable_table_length();
1157   int exception_table_len = cm->exception_table_length();
1158   int method_parameters_len = cm->method_parameters_length();
1159   int method_annotations_len = cm->method_annotations_length();
1160   int parameter_annotations_len = cm->parameter_annotations_length();
1161   int type_annotations_len = cm->type_annotations_length();
1162   int default_annotations_len = cm->default_annotations_length();
1163 
1164   InlineTableSizes sizes(
1165       localvariable_len,
1166       new_compressed_linenumber_size,
1167       exception_table_len,
1168       checked_exceptions_len,
1169       method_parameters_len,
1170       cm->generic_signature_index(),
1171       method_annotations_len,
1172       parameter_annotations_len,
1173       type_annotations_len,
1174       default_annotations_len,
1175       0);
1176 
1177   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1178   Method* newm_oop = Method::allocate(loader_data,
1179                                       new_code_length,
1180                                       flags,
1181                                       &sizes,
1182                                       m->method_type(),
1183                                       CHECK_(methodHandle()));
1184   methodHandle newm (THREAD, newm_oop);
1185   int new_method_size = newm->method_size();
1186 
1187   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1188   ConstMethod* newcm = newm->constMethod();
1189   int new_const_method_size = newm->constMethod()->size();
1190 
1191   memcpy(newm(), m(), sizeof(Method));
1192 
1193   // Create shallow copy of ConstMethod.
1194   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1195 
1196   // Reset correct method/const method, method size, and parameter info
1197   newm->set_constMethod(newcm);
1198   newm->constMethod()->set_code_size(new_code_length);
1199   newm->constMethod()->set_constMethod_size(new_const_method_size);
1200   newm->set_method_size(new_method_size);
1201   assert(newm->code_size() == new_code_length, "check");
1202   assert(newm->method_parameters_length() == method_parameters_len, "check");
1203   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1204   assert(newm->exception_table_length() == exception_table_len, "check");
1205   assert(newm->localvariable_table_length() == localvariable_len, "check");
1206   // Copy new byte codes
1207   memcpy(newm->code_base(), new_code, new_code_length);
1208   // Copy line number table
1209   if (new_compressed_linenumber_size > 0) {
1210     memcpy(newm->compressed_linenumber_table(),
1211            new_compressed_linenumber_table,
1212            new_compressed_linenumber_size);
1213   }
1214   // Copy method_parameters
1215   if (method_parameters_len > 0) {
1216     memcpy(newm->method_parameters_start(),
1217            m->method_parameters_start(),
1218            method_parameters_len * sizeof(MethodParametersElement));
1219   }
1220   // Copy checked_exceptions
1221   if (checked_exceptions_len > 0) {
1222     memcpy(newm->checked_exceptions_start(),
1223            m->checked_exceptions_start(),
1224            checked_exceptions_len * sizeof(CheckedExceptionElement));
1225   }
1226   // Copy exception table
1227   if (exception_table_len > 0) {
1228     memcpy(newm->exception_table_start(),
1229            m->exception_table_start(),
1230            exception_table_len * sizeof(ExceptionTableElement));
1231   }
1232   // Copy local variable number table
1233   if (localvariable_len > 0) {
1234     memcpy(newm->localvariable_table_start(),
1235            m->localvariable_table_start(),
1236            localvariable_len * sizeof(LocalVariableTableElement));
1237   }
1238   // Copy stackmap table
1239   if (m->has_stackmap_table()) {
1240     int code_attribute_length = m->stackmap_data()->length();
1241     Array<u1>* stackmap_data =
1242       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1243     memcpy((void*)stackmap_data->adr_at(0),
1244            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1245     newm->set_stackmap_data(stackmap_data);
1246   }
1247 
1248   // copy annotations over to new method
1249   newcm->copy_annotations_from(cm);
1250   return newm;
1251 }
1252 
1253 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1254   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1255   // because we are not loading from core libraries
1256   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1257   // which does not use the class default class loader so we check for its loader here
1258   InstanceKlass* ik = InstanceKlass::cast(holder);
1259   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1260     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1261   }
1262 
1263   // see if the klass name is well-known:
1264   Symbol* klass_name = ik->name();
1265   return vmSymbols::find_sid(klass_name);
1266 }
1267 
1268 void Method::init_intrinsic_id() {
1269   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1270   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1271   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1272   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1273 
1274   // the klass name is well-known:
1275   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1276   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1277 
1278   // ditto for method and signature:
1279   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1280   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1281       && name_id == vmSymbols::NO_SID)
1282     return;
1283   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1284   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1285       && sig_id == vmSymbols::NO_SID)  return;
1286   jshort flags = access_flags().as_short();
1287 
1288   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1289   if (id != vmIntrinsics::_none) {
1290     set_intrinsic_id(id);
1291     return;
1292   }
1293 
1294   // A few slightly irregular cases:
1295   switch (klass_id) {
1296   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1297     // Second chance: check in regular Math.
1298     switch (name_id) {
1299     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1300     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1301     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1302       // pretend it is the corresponding method in the non-strict class:
1303       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1304       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1305       break;
1306     }
1307     break;
1308 
1309   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1310   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1311     if (!is_native())  break;
1312     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1313     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1314       id = vmIntrinsics::_none;
1315     break;
1316   }
1317 
1318   if (id != vmIntrinsics::_none) {
1319     // Set up its iid.  It is an alias method.
1320     set_intrinsic_id(id);
1321     return;
1322   }
1323 }
1324 
1325 // These two methods are static since a GC may move the Method
1326 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1327   if (THREAD->is_Compiler_thread()) {
1328     // There is nothing useful this routine can do from within the Compile thread.
1329     // Hopefully, the signature contains only well-known classes.
1330     // We could scan for this and return true/false, but the caller won't care.
1331     return false;
1332   }
1333   bool sig_is_loaded = true;
1334   Handle class_loader(THREAD, m->method_holder()->class_loader());
1335   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1336   ResourceMark rm(THREAD);
1337   Symbol*  signature = m->signature();
1338   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1339     if (ss.is_object()) {
1340       Symbol* sym = ss.as_symbol(CHECK_(false));
1341       Symbol*  name  = sym;
1342       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1343                                              protection_domain, THREAD);
1344       // We are loading classes eagerly. If a ClassNotFoundException or
1345       // a LinkageError was generated, be sure to ignore it.
1346       if (HAS_PENDING_EXCEPTION) {
1347         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1348             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1349           CLEAR_PENDING_EXCEPTION;
1350         } else {
1351           return false;
1352         }
1353       }
1354       if( klass == NULL) { sig_is_loaded = false; }
1355     }
1356   }
1357   return sig_is_loaded;
1358 }
1359 
1360 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1361   Handle class_loader(THREAD, m->method_holder()->class_loader());
1362   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1363   ResourceMark rm(THREAD);
1364   Symbol*  signature = m->signature();
1365   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1366     if (ss.type() == T_OBJECT) {
1367       Symbol* name = ss.as_symbol_or_null();
1368       if (name == NULL) return true;
1369       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1370       if (klass == NULL) return true;
1371     }
1372   }
1373   return false;
1374 }
1375 
1376 // Exposed so field engineers can debug VM
1377 void Method::print_short_name(outputStream* st) {
1378   ResourceMark rm;
1379 #ifdef PRODUCT
1380   st->print(" %s::", method_holder()->external_name());
1381 #else
1382   st->print(" %s::", method_holder()->internal_name());
1383 #endif
1384   name()->print_symbol_on(st);
1385   if (WizardMode) signature()->print_symbol_on(st);
1386   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1387     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1388 }
1389 
1390 // Comparer for sorting an object array containing
1391 // Method*s.
1392 static int method_comparator(Method* a, Method* b) {
1393   return a->name()->fast_compare(b->name());
1394 }
1395 
1396 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1397 // default_methods also uses this without the ordering for fast find_method
1398 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1399   int length = methods->length();
1400   if (length > 1) {
1401     {
1402       No_Safepoint_Verifier nsv;
1403       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1404     }
1405     // Reset method ordering
1406     if (set_idnums) {
1407       for (int i = 0; i < length; i++) {
1408         Method* m = methods->at(i);
1409         m->set_method_idnum(i);
1410       }
1411     }
1412   }
1413 }
1414 
1415 //-----------------------------------------------------------------------------------
1416 // Non-product code unless JVM/TI needs it
1417 
1418 #if !defined(PRODUCT) || INCLUDE_JVMTI
1419 class SignatureTypePrinter : public SignatureTypeNames {
1420  private:
1421   outputStream* _st;
1422   bool _use_separator;
1423 
1424   void type_name(const char* name) {
1425     if (_use_separator) _st->print(", ");
1426     _st->print("%s", name);
1427     _use_separator = true;
1428   }
1429 
1430  public:
1431   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1432     _st = st;
1433     _use_separator = false;
1434   }
1435 
1436   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1437   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1438 };
1439 
1440 
1441 void Method::print_name(outputStream* st) {
1442   Thread *thread = Thread::current();
1443   ResourceMark rm(thread);
1444   SignatureTypePrinter sig(signature(), st);
1445   st->print("%s ", is_static() ? "static" : "virtual");
1446   sig.print_returntype();
1447   st->print(" %s.", method_holder()->internal_name());
1448   name()->print_symbol_on(st);
1449   st->print("(");
1450   sig.print_parameters();
1451   st->print(")");
1452 }
1453 #endif // !PRODUCT || INCLUDE_JVMTI
1454 
1455 
1456 void Method::print_codes_on(outputStream* st) const {
1457   print_codes_on(0, code_size(), st);
1458 }
1459 
1460 void Method::print_codes_on(int from, int to, outputStream* st) const {
1461   Thread *thread = Thread::current();
1462   ResourceMark rm(thread);
1463   methodHandle mh (thread, (Method*)this);
1464   BytecodeStream s(mh);
1465   s.set_interval(from, to);
1466   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1467   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1468 }
1469 
1470 
1471 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1472 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1473 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1474 // as end-of-stream terminator.
1475 
1476 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1477   // bci and line number does not compress into single byte.
1478   // Write out escape character and use regular compression for bci and line number.
1479   write_byte((jubyte)0xFF);
1480   write_signed_int(bci_delta);
1481   write_signed_int(line_delta);
1482 }
1483 
1484 // See comment in method.hpp which explains why this exists.
1485 #if defined(_M_AMD64) && _MSC_VER >= 1400
1486 #pragma optimize("", off)
1487 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1488   write_pair_inline(bci, line);
1489 }
1490 #pragma optimize("", on)
1491 #endif
1492 
1493 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1494   _bci = 0;
1495   _line = 0;
1496 };
1497 
1498 
1499 bool CompressedLineNumberReadStream::read_pair() {
1500   jubyte next = read_byte();
1501   // Check for terminator
1502   if (next == 0) return false;
1503   if (next == 0xFF) {
1504     // Escape character, regular compression used
1505     _bci  += read_signed_int();
1506     _line += read_signed_int();
1507   } else {
1508     // Single byte compression used
1509     _bci  += next >> 3;
1510     _line += next & 0x7;
1511   }
1512   return true;
1513 }
1514 
1515 
1516 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1517   BreakpointInfo* bp = method_holder()->breakpoints();
1518   for (; bp != NULL; bp = bp->next()) {
1519     if (bp->match(this, bci)) {
1520       return bp->orig_bytecode();
1521     }
1522   }
1523   {
1524     ResourceMark rm;
1525     fatal(err_msg("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci));
1526   }
1527   return Bytecodes::_shouldnotreachhere;
1528 }
1529 
1530 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1531   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1532   BreakpointInfo* bp = method_holder()->breakpoints();
1533   for (; bp != NULL; bp = bp->next()) {
1534     if (bp->match(this, bci)) {
1535       bp->set_orig_bytecode(code);
1536       // and continue, in case there is more than one
1537     }
1538   }
1539 }
1540 
1541 void Method::set_breakpoint(int bci) {
1542   InstanceKlass* ik = method_holder();
1543   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1544   bp->set_next(ik->breakpoints());
1545   ik->set_breakpoints(bp);
1546   // do this last:
1547   bp->set(this);
1548 }
1549 
1550 static void clear_matches(Method* m, int bci) {
1551   InstanceKlass* ik = m->method_holder();
1552   BreakpointInfo* prev_bp = NULL;
1553   BreakpointInfo* next_bp;
1554   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1555     next_bp = bp->next();
1556     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1557     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1558       // do this first:
1559       bp->clear(m);
1560       // unhook it
1561       if (prev_bp != NULL)
1562         prev_bp->set_next(next_bp);
1563       else
1564         ik->set_breakpoints(next_bp);
1565       delete bp;
1566       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1567       // at same location. So we have multiple matching (method_index and bci)
1568       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1569       // breakpoint for clear_breakpoint request and keep all other method versions
1570       // BreakpointInfo for future clear_breakpoint request.
1571       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1572       // which is being called when class is unloaded. We delete all the Breakpoint
1573       // information for all versions of method. We may not correctly restore the original
1574       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1575       // so these methods won't be used anymore.
1576       if (bci >= 0) {
1577         break;
1578       }
1579     } else {
1580       // This one is a keeper.
1581       prev_bp = bp;
1582     }
1583   }
1584 }
1585 
1586 void Method::clear_breakpoint(int bci) {
1587   assert(bci >= 0, "");
1588   clear_matches(this, bci);
1589 }
1590 
1591 void Method::clear_all_breakpoints() {
1592   clear_matches(this, -1);
1593 }
1594 
1595 
1596 int Method::invocation_count() {
1597   MethodCounters *mcs = method_counters();
1598   if (TieredCompilation) {
1599     MethodData* const mdo = method_data();
1600     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1601         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1602       return InvocationCounter::count_limit;
1603     } else {
1604       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1605              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1606     }
1607   } else {
1608     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1609   }
1610 }
1611 
1612 int Method::backedge_count() {
1613   MethodCounters *mcs = method_counters();
1614   if (TieredCompilation) {
1615     MethodData* const mdo = method_data();
1616     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1617         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1618       return InvocationCounter::count_limit;
1619     } else {
1620       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1621              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1622     }
1623   } else {
1624     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1625   }
1626 }
1627 
1628 int Method::highest_comp_level() const {
1629   const MethodData* mdo = method_data();
1630   if (mdo != NULL) {
1631     return mdo->highest_comp_level();
1632   } else {
1633     return CompLevel_none;
1634   }
1635 }
1636 
1637 int Method::highest_osr_comp_level() const {
1638   const MethodData* mdo = method_data();
1639   if (mdo != NULL) {
1640     return mdo->highest_osr_comp_level();
1641   } else {
1642     return CompLevel_none;
1643   }
1644 }
1645 
1646 void Method::set_highest_comp_level(int level) {
1647   MethodData* mdo = method_data();
1648   if (mdo != NULL) {
1649     mdo->set_highest_comp_level(level);
1650   }
1651 }
1652 
1653 void Method::set_highest_osr_comp_level(int level) {
1654   MethodData* mdo = method_data();
1655   if (mdo != NULL) {
1656     mdo->set_highest_osr_comp_level(level);
1657   }
1658 }
1659 
1660 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1661   _bci = bci;
1662   _name_index = m->name_index();
1663   _signature_index = m->signature_index();
1664   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1665   if (_orig_bytecode == Bytecodes::_breakpoint)
1666     _orig_bytecode = m->orig_bytecode_at(_bci);
1667   _next = NULL;
1668 }
1669 
1670 void BreakpointInfo::set(Method* method) {
1671 #ifdef ASSERT
1672   {
1673     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1674     if (code == Bytecodes::_breakpoint)
1675       code = method->orig_bytecode_at(_bci);
1676     assert(orig_bytecode() == code, "original bytecode must be the same");
1677   }
1678 #endif
1679   Thread *thread = Thread::current();
1680   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1681   method->incr_number_of_breakpoints(thread);
1682   SystemDictionary::notice_modification();
1683   {
1684     // Deoptimize all dependents on this method
1685     HandleMark hm(thread);
1686     methodHandle mh(thread, method);
1687     Universe::flush_dependents_on_method(mh);
1688   }
1689 }
1690 
1691 void BreakpointInfo::clear(Method* method) {
1692   *method->bcp_from(_bci) = orig_bytecode();
1693   assert(method->number_of_breakpoints() > 0, "must not go negative");
1694   method->decr_number_of_breakpoints(Thread::current());
1695 }
1696 
1697 // jmethodID handling
1698 
1699 // This is a block allocating object, sort of like JNIHandleBlock, only a
1700 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1701 // deleted and so we can do some suboptimal things.
1702 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1703 // never get rid of it.
1704 // It would be nice to be able to parameterize the number of methods for
1705 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1706 // into templates.
1707 
1708 // I feel like this brain dead class should exist somewhere in the STL
1709 
1710 class JNIMethodBlock : public CHeapObj<mtClass> {
1711   enum { number_of_methods = 8 };
1712 
1713   Method*         _methods[number_of_methods];
1714   int             _top;
1715   JNIMethodBlock* _next;
1716  public:
1717   static Method* const _free_method;
1718 
1719   JNIMethodBlock() : _next(NULL), _top(0) {
1720     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1721   }
1722 
1723   Method** add_method(Method* m) {
1724     if (_top < number_of_methods) {
1725       // top points to the next free entry.
1726       int i = _top;
1727       _methods[i] = m;
1728       _top++;
1729       return &_methods[i];
1730     } else if (_top == number_of_methods) {
1731       // if the next free entry ran off the block see if there's a free entry
1732       for (int i = 0; i< number_of_methods; i++) {
1733         if (_methods[i] == _free_method) {
1734           _methods[i] = m;
1735           return &_methods[i];
1736         }
1737       }
1738       // Only check each block once for frees.  They're very unlikely.
1739       // Increment top past the end of the block.
1740       _top++;
1741     }
1742     // need to allocate a next block.
1743     if (_next == NULL) {
1744       _next = new JNIMethodBlock();
1745     }
1746     return _next->add_method(m);
1747   }
1748 
1749   bool contains(Method** m) {
1750     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1751       for (int i = 0; i< number_of_methods; i++) {
1752         if (&(b->_methods[i]) == m) {
1753           return true;
1754         }
1755       }
1756     }
1757     return false;  // not found
1758   }
1759 
1760   // Doesn't really destroy it, just marks it as free so it can be reused.
1761   void destroy_method(Method** m) {
1762 #ifdef ASSERT
1763     assert(contains(m), "should be a methodID");
1764 #endif // ASSERT
1765     *m = _free_method;
1766   }
1767 
1768   // During class unloading the methods are cleared, which is different
1769   // than freed.
1770   void clear_all_methods() {
1771     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1772       for (int i = 0; i< number_of_methods; i++) {
1773         _methods[i] = NULL;
1774       }
1775     }
1776   }
1777 #ifndef PRODUCT
1778   int count_methods() {
1779     // count all allocated methods
1780     int count = 0;
1781     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1782       for (int i = 0; i< number_of_methods; i++) {
1783         if (_methods[i] != _free_method) count++;
1784       }
1785     }
1786     return count;
1787   }
1788 #endif // PRODUCT
1789 };
1790 
1791 // Something that can't be mistaken for an address or a markOop
1792 Method* const JNIMethodBlock::_free_method = (Method*)55;
1793 
1794 // Add a method id to the jmethod_ids
1795 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1796   ClassLoaderData* cld = loader_data;
1797 
1798   if (!SafepointSynchronize::is_at_safepoint()) {
1799     // Have to add jmethod_ids() to class loader data thread-safely.
1800     // Also have to add the method to the list safely, which the cld lock
1801     // protects as well.
1802     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1803     if (cld->jmethod_ids() == NULL) {
1804       cld->set_jmethod_ids(new JNIMethodBlock());
1805     }
1806     // jmethodID is a pointer to Method*
1807     return (jmethodID)cld->jmethod_ids()->add_method(m);
1808   } else {
1809     // At safepoint, we are single threaded and can set this.
1810     if (cld->jmethod_ids() == NULL) {
1811       cld->set_jmethod_ids(new JNIMethodBlock());
1812     }
1813     // jmethodID is a pointer to Method*
1814     return (jmethodID)cld->jmethod_ids()->add_method(m);
1815   }
1816 }
1817 
1818 // Mark a jmethodID as free.  This is called when there is a data race in
1819 // InstanceKlass while creating the jmethodID cache.
1820 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1821   ClassLoaderData* cld = loader_data;
1822   Method** ptr = (Method**)m;
1823   assert(cld->jmethod_ids() != NULL, "should have method handles");
1824   cld->jmethod_ids()->destroy_method(ptr);
1825 }
1826 
1827 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1828   // Can't assert the method_holder is the same because the new method has the
1829   // scratch method holder.
1830   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1831            == new_method->method_holder()->class_loader(),
1832          "changing to a different class loader");
1833   // Just change the method in place, jmethodID pointer doesn't change.
1834   *((Method**)jmid) = new_method;
1835 }
1836 
1837 bool Method::is_method_id(jmethodID mid) {
1838   Method* m = resolve_jmethod_id(mid);
1839   assert(m != NULL, "should be called with non-null method");
1840   InstanceKlass* ik = m->method_holder();
1841   ClassLoaderData* cld = ik->class_loader_data();
1842   if (cld->jmethod_ids() == NULL) return false;
1843   return (cld->jmethod_ids()->contains((Method**)mid));
1844 }
1845 
1846 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1847   if (mid == NULL) return NULL;
1848   Method* o = resolve_jmethod_id(mid);
1849   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1850     return NULL;
1851   }
1852   return o;
1853 };
1854 
1855 void Method::set_on_stack(const bool value) {
1856   // Set both the method itself and its constant pool.  The constant pool
1857   // on stack means some method referring to it is also on the stack.
1858   _access_flags.set_on_stack(value);
1859   constants()->set_on_stack(value);
1860   if (value) MetadataOnStackMark::record(this);
1861 }
1862 
1863 // Called when the class loader is unloaded to make all methods weak.
1864 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1865   loader_data->jmethod_ids()->clear_all_methods();
1866 }
1867 
1868 bool Method::has_method_vptr(const void* ptr) {
1869   Method m;
1870   // This assumes that the vtbl pointer is the first word of a C++ object.
1871   // This assumption is also in universe.cpp patch_klass_vtble
1872   void* vtbl2 = dereference_vptr((const void*)&m);
1873   void* this_vtbl = dereference_vptr(ptr);
1874   return vtbl2 == this_vtbl;
1875 }
1876 
1877 // Check that this pointer is valid by checking that the vtbl pointer matches
1878 bool Method::is_valid_method() const {
1879   if (this == NULL) {
1880     return false;
1881   } else if (!is_metaspace_object()) {
1882     return false;
1883   } else {
1884     return has_method_vptr((const void*)this);
1885   }
1886 }
1887 
1888 #ifndef PRODUCT
1889 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1890   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1891 }
1892 #endif // PRODUCT
1893 
1894 
1895 // Printing
1896 
1897 #ifndef PRODUCT
1898 
1899 void Method::print_on(outputStream* st) const {
1900   ResourceMark rm;
1901   assert(is_method(), "must be method");
1902   st->print_cr("%s", internal_name());
1903   // get the effect of PrintOopAddress, always, for methods:
1904   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1905   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1906   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1907   constants()->print_value_on(st); st->cr();
1908   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1909   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1910   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1911   st->print_cr(" - max stack:         %d",   max_stack());
1912   st->print_cr(" - max locals:        %d",   max_locals());
1913   st->print_cr(" - size of params:    %d",   size_of_parameters());
1914   st->print_cr(" - method size:       %d",   method_size());
1915   if (intrinsic_id() != vmIntrinsics::_none)
1916     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1917   if (highest_comp_level() != CompLevel_none)
1918     st->print_cr(" - highest level:     %d", highest_comp_level());
1919   st->print_cr(" - vtable index:      %d",   _vtable_index);
1920   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1921   st->print(   " - adapters:          ");
1922   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1923   if (a == NULL)
1924     st->print_cr(INTPTR_FORMAT, a);
1925   else
1926     a->print_adapter_on(st);
1927   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1928   st->print_cr(" - code size:         %d",   code_size());
1929   if (code_size() != 0) {
1930     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1931     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1932   }
1933   if (method_data() != NULL) {
1934     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1935   }
1936   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1937   if (checked_exceptions_length() > 0) {
1938     CheckedExceptionElement* table = checked_exceptions_start();
1939     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1940     if (Verbose) {
1941       for (int i = 0; i < checked_exceptions_length(); i++) {
1942         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1943       }
1944     }
1945   }
1946   if (has_linenumber_table()) {
1947     u_char* table = compressed_linenumber_table();
1948     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1949     if (Verbose) {
1950       CompressedLineNumberReadStream stream(table);
1951       while (stream.read_pair()) {
1952         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1953       }
1954     }
1955   }
1956   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1957   if (localvariable_table_length() > 0) {
1958     LocalVariableTableElement* table = localvariable_table_start();
1959     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1960     if (Verbose) {
1961       for (int i = 0; i < localvariable_table_length(); i++) {
1962         int bci = table[i].start_bci;
1963         int len = table[i].length;
1964         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1965         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
1966         int slot = table[i].slot;
1967         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
1968       }
1969     }
1970   }
1971   if (code() != NULL) {
1972     st->print   (" - compiled code: ");
1973     code()->print_value_on(st);
1974   }
1975   if (is_native()) {
1976     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
1977     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
1978   }
1979 }
1980 
1981 #endif //PRODUCT
1982 
1983 void Method::print_value_on(outputStream* st) const {
1984   assert(is_method(), "must be method");
1985   st->print("%s", internal_name());
1986   print_address_on(st);
1987   st->print(" ");
1988   name()->print_value_on(st);
1989   st->print(" ");
1990   signature()->print_value_on(st);
1991   st->print(" in ");
1992   method_holder()->print_value_on(st);
1993   if (WizardMode) st->print("#%d", _vtable_index);
1994   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
1995   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
1996 }
1997 
1998 #if INCLUDE_SERVICES
1999 // Size Statistics
2000 void Method::collect_statistics(KlassSizeStats *sz) const {
2001   int mysize = sz->count(this);
2002   sz->_method_bytes += mysize;
2003   sz->_method_all_bytes += mysize;
2004   sz->_rw_bytes += mysize;
2005 
2006   if (constMethod()) {
2007     constMethod()->collect_statistics(sz);
2008   }
2009   if (method_data()) {
2010     method_data()->collect_statistics(sz);
2011   }
2012 }
2013 #endif // INCLUDE_SERVICES
2014 
2015 // Verification
2016 
2017 void Method::verify_on(outputStream* st) {
2018   guarantee(is_method(), "object must be method");
2019   guarantee(constants()->is_constantPool(), "should be constant pool");
2020   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2021   MethodData* md = method_data();
2022   guarantee(md == NULL ||
2023       md->is_methodData(), "should be method data");
2024 }