1 /*
   2  * Copyright (c) 1997, 2016, 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/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "gc/shared/collectedHeap.inline.hpp"
  31 #include "gc/shared/gcLocker.hpp"
  32 #include "gc/shared/generation.hpp"
  33 #include "interpreter/bytecodeStream.hpp"
  34 #include "interpreter/bytecodeTracer.hpp"
  35 #include "interpreter/bytecodes.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/oopMapCache.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/oopFactory.hpp"
  41 #include "oops/constMethod.hpp"
  42 #include "oops/method.hpp"
  43 #include "oops/methodData.hpp"
  44 #include "oops/objArrayOop.inline.hpp"
  45 #include "oops/oop.inline.hpp"
  46 #include "oops/symbol.hpp"
  47 #include "prims/jvmtiExport.hpp"
  48 #include "prims/methodHandles.hpp"
  49 #include "prims/nativeLookup.hpp"
  50 #include "runtime/arguments.hpp"
  51 #include "runtime/compilationPolicy.hpp"
  52 #include "runtime/frame.inline.hpp"
  53 #include "runtime/handles.inline.hpp"
  54 #include "runtime/orderAccess.inline.hpp"
  55 #include "runtime/relocator.hpp"
  56 #include "runtime/sharedRuntime.hpp"
  57 #include "runtime/signature.hpp"
  58 #include "utilities/quickSort.hpp"
  59 #include "utilities/xmlstream.hpp"
  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   int size = Method::size(access_flags.is_native());
  77   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  78 }
  79 
  80 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  81   NoSafepointVerifier no_safepoint;
  82   set_constMethod(xconst);
  83   set_access_flags(access_flags);
  84 #ifdef CC_INTERP
  85   set_result_index(T_VOID);
  86 #endif
  87   set_intrinsic_id(vmIntrinsics::_none);
  88   set_jfr_towrite(false);
  89   set_force_inline(false);
  90   set_hidden(false);
  91   set_dont_inline(false);
  92   set_has_injected_profile(false);
  93   set_method_data(NULL);
  94   clear_method_counters();
  95   set_vtable_index(Method::garbage_vtable_index);
  96 
  97   // Fix and bury in Method*
  98   set_interpreter_entry(NULL); // sets i2i entry and from_int
  99   set_adapter_entry(NULL);
 100   clear_code(); // from_c/from_i get set to c2i/i2i
 101 
 102   if (access_flags.is_native()) {
 103     clear_native_function();
 104     set_signature_handler(NULL);
 105   }
 106 
 107   NOT_PRODUCT(set_compiled_invocation_count(0);)
 108 }
 109 
 110 // Release Method*.  The nmethod will be gone when we get here because
 111 // we've walked the code cache.
 112 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 113   MetadataFactory::free_metadata(loader_data, constMethod());
 114   set_constMethod(NULL);
 115   MetadataFactory::free_metadata(loader_data, method_data());
 116   set_method_data(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_counters());
 118   clear_method_counters();
 119   // The nmethod will be gone when we get here.
 120   if (code() != NULL) _code = NULL;
 121 }
 122 
 123 address Method::get_i2c_entry() {
 124   assert(_adapter != NULL, "must have");
 125   return _adapter->get_i2c_entry();
 126 }
 127 
 128 address Method::get_c2i_entry() {
 129   assert(_adapter != NULL, "must have");
 130   return _adapter->get_c2i_entry();
 131 }
 132 
 133 address Method::get_c2i_unverified_entry() {
 134   assert(_adapter != NULL, "must have");
 135   return _adapter->get_c2i_unverified_entry();
 136 }
 137 
 138 char* Method::name_and_sig_as_C_string() const {
 139   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 140 }
 141 
 142 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 143   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 144 }
 145 
 146 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 147   const char* klass_name = klass->external_name();
 148   int klass_name_len  = (int)strlen(klass_name);
 149   int method_name_len = method_name->utf8_length();
 150   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 151   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 152   strcpy(dest, klass_name);
 153   dest[klass_name_len] = '.';
 154   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 155   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 156   dest[len] = 0;
 157   return dest;
 158 }
 159 
 160 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 161   Symbol* klass_name = klass->name();
 162   klass_name->as_klass_external_name(buf, size);
 163   int len = (int)strlen(buf);
 164 
 165   if (len < size - 1) {
 166     buf[len++] = '.';
 167 
 168     method_name->as_C_string(&(buf[len]), size - len);
 169     len = (int)strlen(buf);
 170 
 171     signature->as_C_string(&(buf[len]), size - len);
 172   }
 173 
 174   return buf;
 175 }
 176 
 177 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 178   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 179   // access exception table
 180   ExceptionTable table(mh());
 181   int length = table.length();
 182   // iterate through all entries sequentially
 183   constantPoolHandle pool(THREAD, mh->constants());
 184   for (int i = 0; i < length; i ++) {
 185     //reacquire the table in case a GC happened
 186     ExceptionTable table(mh());
 187     int beg_bci = table.start_pc(i);
 188     int end_bci = table.end_pc(i);
 189     assert(beg_bci <= end_bci, "inconsistent exception table");
 190     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 191       // exception handler bci range covers throw_bci => investigate further
 192       int handler_bci = table.handler_pc(i);
 193       int klass_index = table.catch_type_index(i);
 194       if (klass_index == 0) {
 195         return handler_bci;
 196       } else if (ex_klass.is_null()) {
 197         return handler_bci;
 198       } else {
 199         // we know the exception class => get the constraint class
 200         // this may require loading of the constraint class; if verification
 201         // fails or some other exception occurs, return handler_bci
 202         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 203         KlassHandle klass = KlassHandle(THREAD, k);
 204         assert(klass.not_null(), "klass not loaded");
 205         if (ex_klass->is_subtype_of(klass())) {
 206           return handler_bci;
 207         }
 208       }
 209     }
 210   }
 211 
 212   return -1;
 213 }
 214 
 215 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 216 
 217   Thread* myThread    = Thread::current();
 218   methodHandle h_this(myThread, this);
 219 #if defined(ASSERT) && !INCLUDE_JVMCI
 220   bool has_capability = myThread->is_VM_thread() ||
 221                         myThread->is_ConcurrentGC_thread() ||
 222                         myThread->is_GC_task_thread();
 223 
 224   if (!has_capability) {
 225     if (!VerifyStack && !VerifyLastFrame) {
 226       // verify stack calls this outside VM thread
 227       warning("oopmap should only be accessed by the "
 228               "VM, GC task or CMS threads (or during debugging)");
 229       InterpreterOopMap local_mask;
 230       method_holder()->mask_for(h_this, bci, &local_mask);
 231       local_mask.print();
 232     }
 233   }
 234 #endif
 235   method_holder()->mask_for(h_this, bci, mask);
 236   return;
 237 }
 238 
 239 
 240 int Method::bci_from(address bcp) const {
 241   if (is_native() && bcp == 0) {
 242     return 0;
 243   }
 244 #ifdef ASSERT
 245   {
 246     ResourceMark rm;
 247     assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 248            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 249            p2i(bcp), name_and_sig_as_C_string());
 250   }
 251 #endif
 252   return bcp - code_base();
 253 }
 254 
 255 
 256 int Method::validate_bci(int bci) const {
 257   return (bci == 0 || bci < code_size()) ? bci : -1;
 258 }
 259 
 260 // Return bci 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_bcp(address bcp) const {
 265   // keep bci as -1 if not a valid bci
 266   int bci = -1;
 267   if (bcp == 0 || bcp == 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 (contains(bcp)) {
 272     bci = bcp - code_base();
 273   }
 274   // Assert that if we have dodged any asserts, bci is negative.
 275   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 276   return bci;
 277 }
 278 
 279 address Method::bcp_from(int bci) const {
 280   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()), "illegal bci: %d", bci);
 281   address bcp = code_base() + bci;
 282   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 283   return bcp;
 284 }
 285 
 286 address Method::bcp_from(address bcp) const {
 287   if (is_native() && bcp == NULL) {
 288     return code_base();
 289   } else {
 290     return bcp;
 291   }
 292 }
 293 
 294 int Method::size(bool is_native) {
 295   // If native, then include pointers for native_function and signature_handler
 296   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 297   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 298   return align_metadata_size(header_size() + extra_words);
 299 }
 300 
 301 
 302 Symbol* Method::klass_name() const {
 303   return method_holder()->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 ((method_counters() != NULL &&
 327             method_counters()->invocation_counter()->carry()) ||
 328            (method_data() != NULL &&
 329             method_data()->invocation_counter()->carry())) {
 330     // The carry bit is set when the counter overflows and causes
 331     // a compilation to occur.  We don't know how many times
 332     // the counter has been reset, so we simply assume it has
 333     // been executed more than n times.
 334     return true;
 335   } else {
 336     return invocation_count() > n;
 337   }
 338 }
 339 
 340 void Method::print_invocation_count() {
 341   if (is_static()) tty->print("static ");
 342   if (is_final()) tty->print("final ");
 343   if (is_synchronized()) tty->print("synchronized ");
 344   if (is_native()) tty->print("native ");
 345   tty->print("%s::", method_holder()->external_name());
 346   name()->print_symbol_on(tty);
 347   signature()->print_symbol_on(tty);
 348 
 349   if (WizardMode) {
 350     // dump the size of the byte codes
 351     tty->print(" {%d}", code_size());
 352   }
 353   tty->cr();
 354 
 355   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 356   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 357   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 358 #ifndef PRODUCT
 359   if (CountCompiledCalls) {
 360     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 361   }
 362 #endif
 363 }
 364 
 365 // Build a MethodData* object to hold information about this method
 366 // collected in the interpreter.
 367 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 368   // Do not profile the method if metaspace has hit an OOM previously
 369   // allocating profiling data. Callers clear pending exception so don't
 370   // add one here.
 371   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 372     return;
 373   }
 374 
 375   // Do not profile method if current thread holds the pending list lock,
 376   // which avoids deadlock for acquiring the MethodData_lock.
 377   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 378     return;
 379   }
 380 
 381   // Grab a lock here to prevent multiple
 382   // MethodData*s from being created.
 383   MutexLocker ml(MethodData_lock, THREAD);
 384   if (method->method_data() == NULL) {
 385     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 386     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 387     if (HAS_PENDING_EXCEPTION) {
 388       CompileBroker::log_metaspace_failure();
 389       ClassLoaderDataGraph::set_metaspace_oom(true);
 390       return;   // return the exception (which is cleared)
 391     }
 392 
 393     method->set_method_data(method_data);
 394     if (PrintMethodData && (Verbose || WizardMode)) {
 395       ResourceMark rm(THREAD);
 396       tty->print("build_interpreter_method_data for ");
 397       method->print_name(tty);
 398       tty->cr();
 399       // At the end of the run, the MDO, full of data, will be dumped.
 400     }
 401   }
 402 }
 403 
 404 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 405   // Do not profile the method if metaspace has hit an OOM previously
 406   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 407     return NULL;
 408   }
 409 
 410   methodHandle mh(m);
 411   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 412   if (HAS_PENDING_EXCEPTION) {
 413     CompileBroker::log_metaspace_failure();
 414     ClassLoaderDataGraph::set_metaspace_oom(true);
 415     return NULL;   // return the exception (which is cleared)
 416   }
 417   if (!mh->init_method_counters(counters)) {
 418     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 419   }
 420 
 421   if (LogTouchedMethods) {
 422     mh->log_touched(CHECK_NULL);
 423   }
 424 
 425   return mh->method_counters();
 426 }
 427 
 428 void Method::cleanup_inline_caches() {
 429   // The current system doesn't use inline caches in the interpreter
 430   // => nothing to do (keep this method around for future use)
 431 }
 432 
 433 
 434 int Method::extra_stack_words() {
 435   // not an inline function, to avoid a header dependency on Interpreter
 436   return extra_stack_entries() * Interpreter::stackElementSize;
 437 }
 438 
 439 
 440 void Method::compute_size_of_parameters(Thread *thread) {
 441   ArgumentSizeComputer asc(signature());
 442   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 443 }
 444 
 445 #ifdef CC_INTERP
 446 void Method::set_result_index(BasicType type)          {
 447   _result_index = Interpreter::BasicType_as_index(type);
 448 }
 449 #endif
 450 
 451 BasicType Method::result_type() const {
 452   ResultTypeFinder rtf(signature());
 453   return rtf.type();
 454 }
 455 
 456 
 457 bool Method::is_empty_method() const {
 458   return  code_size() == 1
 459       && *code_base() == Bytecodes::_return;
 460 }
 461 
 462 
 463 bool Method::is_vanilla_constructor() const {
 464   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 465   // which only calls the superclass vanilla constructor and possibly does stores of
 466   // zero constants to local fields:
 467   //
 468   //   aload_0
 469   //   invokespecial
 470   //   indexbyte1
 471   //   indexbyte2
 472   //
 473   // followed by an (optional) sequence of:
 474   //
 475   //   aload_0
 476   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 477   //   putfield
 478   //   indexbyte1
 479   //   indexbyte2
 480   //
 481   // followed by:
 482   //
 483   //   return
 484 
 485   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 486   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 487   int size = code_size();
 488   // Check if size match
 489   if (size == 0 || size % 5 != 0) return false;
 490   address cb = code_base();
 491   int last = size - 1;
 492   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 493     // Does not call superclass default constructor
 494     return false;
 495   }
 496   // Check optional sequence
 497   for (int i = 4; i < last; i += 5) {
 498     if (cb[i] != Bytecodes::_aload_0) return false;
 499     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 500     if (cb[i+2] != Bytecodes::_putfield) return false;
 501   }
 502   return true;
 503 }
 504 
 505 
 506 bool Method::compute_has_loops_flag() {
 507   BytecodeStream bcs(this);
 508   Bytecodes::Code bc;
 509 
 510   while ((bc = bcs.next()) >= 0) {
 511     switch( bc ) {
 512       case Bytecodes::_ifeq:
 513       case Bytecodes::_ifnull:
 514       case Bytecodes::_iflt:
 515       case Bytecodes::_ifle:
 516       case Bytecodes::_ifne:
 517       case Bytecodes::_ifnonnull:
 518       case Bytecodes::_ifgt:
 519       case Bytecodes::_ifge:
 520       case Bytecodes::_if_icmpeq:
 521       case Bytecodes::_if_icmpne:
 522       case Bytecodes::_if_icmplt:
 523       case Bytecodes::_if_icmpgt:
 524       case Bytecodes::_if_icmple:
 525       case Bytecodes::_if_icmpge:
 526       case Bytecodes::_if_acmpeq:
 527       case Bytecodes::_if_acmpne:
 528       case Bytecodes::_goto:
 529       case Bytecodes::_jsr:
 530         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 531         break;
 532 
 533       case Bytecodes::_goto_w:
 534       case Bytecodes::_jsr_w:
 535         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 536         break;
 537     }
 538   }
 539   _access_flags.set_loops_flag_init();
 540   return _access_flags.has_loops();
 541 }
 542 
 543 bool Method::is_final_method(AccessFlags class_access_flags) const {
 544   // or "does_not_require_vtable_entry"
 545   // default method or overpass can occur, is not final (reuses vtable entry)
 546   // private methods get vtable entries for backward class compatibility.
 547   if (is_overpass() || is_default_method())  return false;
 548   return is_final() || class_access_flags.is_final();
 549 }
 550 
 551 bool Method::is_final_method() const {
 552   return is_final_method(method_holder()->access_flags());
 553 }
 554 
 555 bool Method::is_default_method() const {
 556   if (method_holder() != NULL &&
 557       method_holder()->is_interface() &&
 558       !is_abstract()) {
 559     return true;
 560   } else {
 561     return false;
 562   }
 563 }
 564 
 565 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 566   if (is_final_method(class_access_flags))  return true;
 567 #ifdef ASSERT
 568   ResourceMark rm;
 569   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 570   if (class_access_flags.is_interface()) {
 571     assert(is_nonv == is_static(), "is_nonv=%s", name_and_sig_as_C_string());
 572   }
 573 #endif
 574   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 575   return vtable_index() == nonvirtual_vtable_index;
 576 }
 577 
 578 bool Method::can_be_statically_bound() const {
 579   return can_be_statically_bound(method_holder()->access_flags());
 580 }
 581 
 582 bool Method::is_accessor() const {
 583   return is_getter() || is_setter();
 584 }
 585 
 586 bool Method::is_getter() const {
 587   if (code_size() != 5) return false;
 588   if (size_of_parameters() != 1) return false;
 589   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 590   if (java_code_at(1) != Bytecodes::_getfield) return false;
 591   switch (java_code_at(4)) {
 592     case Bytecodes::_ireturn:
 593     case Bytecodes::_lreturn:
 594     case Bytecodes::_freturn:
 595     case Bytecodes::_dreturn:
 596     case Bytecodes::_areturn:
 597       break;
 598     default:
 599       return false;
 600   }
 601   return true;
 602 }
 603 
 604 bool Method::is_setter() const {
 605   if (code_size() != 6) return false;
 606   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 607   switch (java_code_at(1)) {
 608     case Bytecodes::_iload_1:
 609     case Bytecodes::_aload_1:
 610     case Bytecodes::_fload_1:
 611       if (size_of_parameters() != 2) return false;
 612       break;
 613     case Bytecodes::_dload_1:
 614     case Bytecodes::_lload_1:
 615       if (size_of_parameters() != 3) return false;
 616       break;
 617     default:
 618       return false;
 619   }
 620   if (java_code_at(2) != Bytecodes::_putfield) return false;
 621   if (java_code_at(5) != Bytecodes::_return)   return false;
 622   return true;
 623 }
 624 
 625 bool Method::is_constant_getter() const {
 626   int last_index = code_size() - 1;
 627   // Check if the first 1-3 bytecodes are a constant push
 628   // and the last bytecode is a return.
 629   return (2 <= code_size() && code_size() <= 4 &&
 630           Bytecodes::is_const(java_code_at(0)) &&
 631           Bytecodes::length_for(java_code_at(0)) == last_index &&
 632           Bytecodes::is_return(java_code_at(last_index)));
 633 }
 634 
 635 bool Method::is_initializer() const {
 636   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 637 }
 638 
 639 bool Method::has_valid_initializer_flags() const {
 640   return (is_static() ||
 641           method_holder()->major_version() < 51);
 642 }
 643 
 644 bool Method::is_static_initializer() const {
 645   // For classfiles version 51 or greater, ensure that the clinit method is
 646   // static.  Non-static methods with the name "<clinit>" are not static
 647   // initializers. (older classfiles exempted for backward compatibility)
 648   return name() == vmSymbols::class_initializer_name() &&
 649          has_valid_initializer_flags();
 650 }
 651 
 652 
 653 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 654   int length = method->checked_exceptions_length();
 655   if (length == 0) {  // common case
 656     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 657   } else {
 658     methodHandle h_this(THREAD, method);
 659     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 660     objArrayHandle mirrors (THREAD, m_oop);
 661     for (int i = 0; i < length; i++) {
 662       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 663       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 664       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 665       mirrors->obj_at_put(i, k->java_mirror());
 666     }
 667     return mirrors;
 668   }
 669 };
 670 
 671 
 672 int Method::line_number_from_bci(int bci) const {
 673   if (bci == SynchronizationEntryBCI) bci = 0;
 674   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 675   int best_bci  =  0;
 676   int best_line = -1;
 677 
 678   if (has_linenumber_table()) {
 679     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 680     // Not necessarily sorted and not necessarily one-to-one.
 681     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 682     while (stream.read_pair()) {
 683       if (stream.bci() == bci) {
 684         // perfect match
 685         return stream.line();
 686       } else {
 687         // update best_bci/line
 688         if (stream.bci() < bci && stream.bci() >= best_bci) {
 689           best_bci  = stream.bci();
 690           best_line = stream.line();
 691         }
 692       }
 693     }
 694   }
 695   return best_line;
 696 }
 697 
 698 
 699 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 700   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 701     Thread *thread = Thread::current();
 702     Symbol* klass_name = constants()->klass_name_at(klass_index);
 703     Handle loader(thread, method_holder()->class_loader());
 704     Handle prot  (thread, method_holder()->protection_domain());
 705     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 706   } else {
 707     return true;
 708   }
 709 }
 710 
 711 
 712 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 713   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 714   if (must_be_resolved) {
 715     // Make sure klass is resolved in constantpool.
 716     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 717   }
 718   return is_klass_loaded_by_klass_index(klass_index);
 719 }
 720 
 721 
 722 void Method::set_native_function(address function, bool post_event_flag) {
 723   assert(function != NULL, "use clear_native_function to unregister natives");
 724   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 725   address* native_function = native_function_addr();
 726 
 727   // We can see racers trying to place the same native function into place. Once
 728   // is plenty.
 729   address current = *native_function;
 730   if (current == function) return;
 731   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 732       function != NULL) {
 733     // native_method_throw_unsatisfied_link_error_entry() should only
 734     // be passed when post_event_flag is false.
 735     assert(function !=
 736       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 737       "post_event_flag mis-match");
 738 
 739     // post the bind event, and possible change the bind function
 740     JvmtiExport::post_native_method_bind(this, &function);
 741   }
 742   *native_function = function;
 743   // This function can be called more than once. We must make sure that we always
 744   // use the latest registered method -> check if a stub already has been generated.
 745   // If so, we have to make it not_entrant.
 746   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 747   if (nm != NULL) {
 748     nm->make_not_entrant();
 749   }
 750 }
 751 
 752 
 753 bool Method::has_native_function() const {
 754   if (is_method_handle_intrinsic())
 755     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 756   address func = native_function();
 757   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 758 }
 759 
 760 
 761 void Method::clear_native_function() {
 762   // Note: is_method_handle_intrinsic() is allowed here.
 763   set_native_function(
 764     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 765     !native_bind_event_is_interesting);
 766   clear_code();
 767 }
 768 
 769 address Method::critical_native_function() {
 770   methodHandle mh(this);
 771   return NativeLookup::lookup_critical_entry(mh);
 772 }
 773 
 774 
 775 void Method::set_signature_handler(address handler) {
 776   address* signature_handler =  signature_handler_addr();
 777   *signature_handler = handler;
 778 }
 779 
 780 
 781 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 782   if (PrintCompilation && report) {
 783     ttyLocker ttyl;
 784     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 785     if (comp_level == CompLevel_all) {
 786       tty->print("all levels ");
 787     } else {
 788       tty->print("levels ");
 789       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 790         tty->print("%d ", i);
 791       }
 792     }
 793     this->print_short_name(tty);
 794     int size = this->code_size();
 795     if (size > 0) {
 796       tty->print(" (%d bytes)", size);
 797     }
 798     if (reason != NULL) {
 799       tty->print("   %s", reason);
 800     }
 801     tty->cr();
 802   }
 803   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 804     ttyLocker ttyl;
 805     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 806                      os::current_thread_id(), is_osr, comp_level);
 807     if (reason != NULL) {
 808       xtty->print(" reason=\'%s\'", reason);
 809     }
 810     xtty->method(this);
 811     xtty->stamp();
 812     xtty->end_elem();
 813   }
 814 }
 815 
 816 bool Method::is_always_compilable() const {
 817   // Generated adapters must be compiled
 818   if (is_method_handle_intrinsic() && is_synthetic()) {
 819     assert(!is_not_c1_compilable(), "sanity check");
 820     assert(!is_not_c2_compilable(), "sanity check");
 821     return true;
 822   }
 823 
 824   return false;
 825 }
 826 
 827 bool Method::is_not_compilable(int comp_level) const {
 828   if (number_of_breakpoints() > 0)
 829     return true;
 830   if (is_always_compilable())
 831     return false;
 832   if (comp_level == CompLevel_any)
 833     return is_not_c1_compilable() || is_not_c2_compilable();
 834   if (is_c1_compile(comp_level))
 835     return is_not_c1_compilable();
 836   if (is_c2_compile(comp_level))
 837     return is_not_c2_compilable();
 838   return false;
 839 }
 840 
 841 // call this when compiler finds that this method is not compilable
 842 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 843   if (is_always_compilable()) {
 844     // Don't mark a method which should be always compilable
 845     return;
 846   }
 847   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 848   if (comp_level == CompLevel_all) {
 849     set_not_c1_compilable();
 850     set_not_c2_compilable();
 851   } else {
 852     if (is_c1_compile(comp_level))
 853       set_not_c1_compilable();
 854     if (is_c2_compile(comp_level))
 855       set_not_c2_compilable();
 856   }
 857   CompilationPolicy::policy()->disable_compilation(this);
 858   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 859 }
 860 
 861 bool Method::is_not_osr_compilable(int comp_level) const {
 862   if (is_not_compilable(comp_level))
 863     return true;
 864   if (comp_level == CompLevel_any)
 865     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 866   if (is_c1_compile(comp_level))
 867     return is_not_c1_osr_compilable();
 868   if (is_c2_compile(comp_level))
 869     return is_not_c2_osr_compilable();
 870   return false;
 871 }
 872 
 873 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 874   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 875   if (comp_level == CompLevel_all) {
 876     set_not_c1_osr_compilable();
 877     set_not_c2_osr_compilable();
 878   } else {
 879     if (is_c1_compile(comp_level))
 880       set_not_c1_osr_compilable();
 881     if (is_c2_compile(comp_level))
 882       set_not_c2_osr_compilable();
 883   }
 884   CompilationPolicy::policy()->disable_compilation(this);
 885   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 886 }
 887 
 888 // Revert to using the interpreter and clear out the nmethod
 889 void Method::clear_code() {
 890 
 891   // this may be NULL if c2i adapters have not been made yet
 892   // Only should happen at allocate time.
 893   if (_adapter == NULL) {
 894     _from_compiled_entry    = NULL;
 895   } else {
 896     _from_compiled_entry    = _adapter->get_c2i_entry();
 897   }
 898   OrderAccess::storestore();
 899   _from_interpreted_entry = _i2i_entry;
 900   OrderAccess::storestore();
 901   _code = NULL;
 902 }
 903 
 904 // Called by class data sharing to remove any entry points (which are not shared)
 905 void Method::unlink_method() {
 906   _code = NULL;
 907   _i2i_entry = NULL;
 908   _from_interpreted_entry = NULL;
 909   if (is_native()) {
 910     *native_function_addr() = NULL;
 911     set_signature_handler(NULL);
 912   }
 913   NOT_PRODUCT(set_compiled_invocation_count(0);)
 914   _adapter = NULL;
 915   _from_compiled_entry = NULL;
 916 
 917   // In case of DumpSharedSpaces, _method_data should always be NULL.
 918   //
 919   // During runtime (!DumpSharedSpaces), when we are cleaning a
 920   // shared class that failed to load, this->link_method() may
 921   // have already been called (before an exception happened), so
 922   // this->_method_data may not be NULL.
 923   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 924 
 925   set_method_data(NULL);
 926   clear_method_counters();
 927 }
 928 
 929 // Called when the method_holder is getting linked. Setup entrypoints so the method
 930 // is ready to be called from interpreter, compiler, and vtables.
 931 void Method::link_method(const methodHandle& h_method, TRAPS) {
 932   // If the code cache is full, we may reenter this function for the
 933   // leftover methods that weren't linked.
 934   if (_i2i_entry != NULL) return;
 935 
 936   assert(_adapter == NULL, "init'd to NULL" );
 937   assert( _code == NULL, "nothing compiled yet" );
 938 
 939   // Setup interpreter entrypoint
 940   assert(this == h_method(), "wrong h_method()" );
 941   address entry = Interpreter::entry_for_method(h_method);
 942   assert(entry != NULL, "interpreter entry must be non-null");
 943   // Sets both _i2i_entry and _from_interpreted_entry
 944   set_interpreter_entry(entry);
 945 
 946   // Don't overwrite already registered native entries.
 947   if (is_native() && !has_native_function()) {
 948     set_native_function(
 949       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 950       !native_bind_event_is_interesting);
 951   }
 952 
 953   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 954   // special handling of vtables.  An alternative is to make adapters more
 955   // lazily by calling make_adapter() from from_compiled_entry() for the
 956   // normal calls.  For vtable calls life gets more complicated.  When a
 957   // call-site goes mega-morphic we need adapters in all methods which can be
 958   // called from the vtable.  We need adapters on such methods that get loaded
 959   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 960   // problem we'll make these lazily later.
 961   (void) make_adapters(h_method, CHECK);
 962 
 963   // ONLY USE the h_method now as make_adapter may have blocked
 964 
 965 }
 966 
 967 address Method::make_adapters(methodHandle mh, TRAPS) {
 968   // Adapters for compiled code are made eagerly here.  They are fairly
 969   // small (generally < 100 bytes) and quick to make (and cached and shared)
 970   // so making them eagerly shouldn't be too expensive.
 971   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 972   if (adapter == NULL ) {
 973     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
 974   }
 975 
 976   mh->set_adapter_entry(adapter);
 977   mh->_from_compiled_entry = adapter->get_c2i_entry();
 978   return adapter->get_c2i_entry();
 979 }
 980 
 981 void Method::restore_unshareable_info(TRAPS) {
 982   // Since restore_unshareable_info can be called more than once for a method, don't
 983   // redo any work.   If this field is restored, there is nothing to do.
 984   if (_from_compiled_entry == NULL) {
 985     // restore method's vtable by calling a virtual function
 986     restore_vtable();
 987 
 988     methodHandle mh(THREAD, this);
 989     link_method(mh, CHECK);
 990   }
 991 }
 992 
 993 
 994 // The verified_code_entry() must be called when a invoke is resolved
 995 // on this method.
 996 
 997 // It returns the compiled code entry point, after asserting not null.
 998 // This function is called after potential safepoints so that nmethod
 999 // or adapter that it points to is still live and valid.
1000 // This function must not hit a safepoint!
1001 address Method::verified_code_entry() {
1002   debug_only(NoSafepointVerifier nsv;)
1003   assert(_from_compiled_entry != NULL, "must be set");
1004   return _from_compiled_entry;
1005 }
1006 
1007 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1008 // (could be racing a deopt).
1009 // Not inline to avoid circular ref.
1010 bool Method::check_code() const {
1011   // cached in a register or local.  There's a race on the value of the field.
1012   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1013   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1014 }
1015 
1016 // Install compiled code.  Instantly it can execute.
1017 void Method::set_code(methodHandle mh, nmethod *code) {
1018   assert( code, "use clear_code to remove code" );
1019   assert( mh->check_code(), "" );
1020 
1021   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1022 
1023   // These writes must happen in this order, because the interpreter will
1024   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1025   // which jumps to _from_compiled_entry.
1026   mh->_code = code;             // Assign before allowing compiled code to exec
1027 
1028   int comp_level = code->comp_level();
1029   // In theory there could be a race here. In practice it is unlikely
1030   // and not worth worrying about.
1031   if (comp_level > mh->highest_comp_level()) {
1032     mh->set_highest_comp_level(comp_level);
1033   }
1034 
1035   OrderAccess::storestore();
1036 #ifdef SHARK
1037   mh->_from_interpreted_entry = code->insts_begin();
1038 #else //!SHARK
1039   mh->_from_compiled_entry = code->verified_entry_point();
1040   OrderAccess::storestore();
1041   // Instantly compiled code can execute.
1042   if (!mh->is_method_handle_intrinsic())
1043     mh->_from_interpreted_entry = mh->get_i2c_entry();
1044 #endif //!SHARK
1045 }
1046 
1047 
1048 bool Method::is_overridden_in(Klass* k) const {
1049   InstanceKlass* ik = InstanceKlass::cast(k);
1050 
1051   if (ik->is_interface()) return false;
1052 
1053   // If method is an interface, we skip it - except if it
1054   // is a miranda method
1055   if (method_holder()->is_interface()) {
1056     // Check that method is not a miranda method
1057     if (ik->lookup_method(name(), signature()) == NULL) {
1058       // No implementation exist - so miranda method
1059       return false;
1060     }
1061     return true;
1062   }
1063 
1064   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1065   assert(ik->vtable() != NULL, "vtable should exist");
1066   if (!has_vtable_index()) {
1067     return false;
1068   } else {
1069     Method* vt_m = ik->method_at_vtable(vtable_index());
1070     return vt_m != this;
1071   }
1072 }
1073 
1074 
1075 // give advice about whether this Method* should be cached or not
1076 bool Method::should_not_be_cached() const {
1077   if (is_old()) {
1078     // This method has been redefined. It is either EMCP or obsolete
1079     // and we don't want to cache it because that would pin the method
1080     // down and prevent it from being collectible if and when it
1081     // finishes executing.
1082     return true;
1083   }
1084 
1085   // caching this method should be just fine
1086   return false;
1087 }
1088 
1089 
1090 /**
1091  *  Returns true if this is one of the specially treated methods for
1092  *  security related stack walks (like Reflection.getCallerClass).
1093  */
1094 bool Method::is_ignored_by_security_stack_walk() const {
1095   if (intrinsic_id() == vmIntrinsics::_invoke) {
1096     // This is Method.invoke() -- ignore it
1097     return true;
1098   }
1099   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1100     // This is an auxilary frame -- ignore it
1101     return true;
1102   }
1103   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1104     // This is an internal adapter frame for method handles -- ignore it
1105     return true;
1106   }
1107   return false;
1108 }
1109 
1110 
1111 // Constant pool structure for invoke methods:
1112 enum {
1113   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1114   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1115   _imcp_limit
1116 };
1117 
1118 // Test if this method is an MH adapter frame generated by Java code.
1119 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1120 bool Method::is_compiled_lambda_form() const {
1121   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1122 }
1123 
1124 // Test if this method is an internal MH primitive method.
1125 bool Method::is_method_handle_intrinsic() const {
1126   vmIntrinsics::ID iid = intrinsic_id();
1127   return (MethodHandles::is_signature_polymorphic(iid) &&
1128           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1129 }
1130 
1131 bool Method::has_member_arg() const {
1132   vmIntrinsics::ID iid = intrinsic_id();
1133   return (MethodHandles::is_signature_polymorphic(iid) &&
1134           MethodHandles::has_member_arg(iid));
1135 }
1136 
1137 // Make an instance of a signature-polymorphic internal MH primitive.
1138 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1139                                                          Symbol* signature,
1140                                                          TRAPS) {
1141   ResourceMark rm;
1142   methodHandle empty;
1143 
1144   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1145   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1146   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1147   if (TraceMethodHandles) {
1148     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1149   }
1150 
1151   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1152   name->increment_refcount();
1153   signature->increment_refcount();
1154 
1155   int cp_length = _imcp_limit;
1156   ClassLoaderData* loader_data = holder->class_loader_data();
1157   constantPoolHandle cp;
1158   {
1159     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1160     cp = constantPoolHandle(THREAD, cp_oop);
1161   }
1162   cp->set_pool_holder(InstanceKlass::cast(holder()));
1163   cp->symbol_at_put(_imcp_invoke_name,       name);
1164   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1165   cp->set_has_preresolution();
1166 
1167   // decide on access bits:  public or not?
1168   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1169   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1170   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1171   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1172 
1173   methodHandle m;
1174   {
1175     InlineTableSizes sizes;
1176     Method* m_oop = Method::allocate(loader_data, 0,
1177                                      accessFlags_from(flags_bits), &sizes,
1178                                      ConstMethod::NORMAL, CHECK_(empty));
1179     m = methodHandle(THREAD, m_oop);
1180   }
1181   m->set_constants(cp());
1182   m->set_name_index(_imcp_invoke_name);
1183   m->set_signature_index(_imcp_invoke_signature);
1184   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1185   assert(m->signature() == signature, "");
1186 #ifdef CC_INTERP
1187   ResultTypeFinder rtf(signature);
1188   m->set_result_index(rtf.type());
1189 #endif
1190   m->compute_size_of_parameters(THREAD);
1191   m->init_intrinsic_id();
1192   assert(m->is_method_handle_intrinsic(), "");
1193 #ifdef ASSERT
1194   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1195   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1196   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1197 #endif //ASSERT
1198 
1199   // Finally, set up its entry points.
1200   assert(m->can_be_statically_bound(), "");
1201   m->set_vtable_index(Method::nonvirtual_vtable_index);
1202   m->link_method(m, CHECK_(empty));
1203 
1204   if (TraceMethodHandles && (Verbose || WizardMode)) {
1205     ttyLocker ttyl;
1206     m->print_on(tty);
1207   }
1208 
1209   return m;
1210 }
1211 
1212 Klass* Method::check_non_bcp_klass(Klass* klass) {
1213   if (klass != NULL && klass->class_loader() != NULL) {
1214     if (klass->is_objArray_klass())
1215       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1216     return klass;
1217   }
1218   return NULL;
1219 }
1220 
1221 
1222 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1223                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1224   // Code below does not work for native methods - they should never get rewritten anyway
1225   assert(!m->is_native(), "cannot rewrite native methods");
1226   // Allocate new Method*
1227   AccessFlags flags = m->access_flags();
1228 
1229   ConstMethod* cm = m->constMethod();
1230   int checked_exceptions_len = cm->checked_exceptions_length();
1231   int localvariable_len = cm->localvariable_table_length();
1232   int exception_table_len = cm->exception_table_length();
1233   int method_parameters_len = cm->method_parameters_length();
1234   int method_annotations_len = cm->method_annotations_length();
1235   int parameter_annotations_len = cm->parameter_annotations_length();
1236   int type_annotations_len = cm->type_annotations_length();
1237   int default_annotations_len = cm->default_annotations_length();
1238 
1239   InlineTableSizes sizes(
1240       localvariable_len,
1241       new_compressed_linenumber_size,
1242       exception_table_len,
1243       checked_exceptions_len,
1244       method_parameters_len,
1245       cm->generic_signature_index(),
1246       method_annotations_len,
1247       parameter_annotations_len,
1248       type_annotations_len,
1249       default_annotations_len,
1250       0);
1251 
1252   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1253   Method* newm_oop = Method::allocate(loader_data,
1254                                       new_code_length,
1255                                       flags,
1256                                       &sizes,
1257                                       m->method_type(),
1258                                       CHECK_(methodHandle()));
1259   methodHandle newm (THREAD, newm_oop);
1260 
1261   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1262   ConstMethod* newcm = newm->constMethod();
1263   int new_const_method_size = newm->constMethod()->size();
1264 
1265   memcpy(newm(), m(), sizeof(Method));
1266 
1267   // Create shallow copy of ConstMethod.
1268   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1269 
1270   // Reset correct method/const method, method size, and parameter info
1271   newm->set_constMethod(newcm);
1272   newm->constMethod()->set_code_size(new_code_length);
1273   newm->constMethod()->set_constMethod_size(new_const_method_size);
1274   assert(newm->code_size() == new_code_length, "check");
1275   assert(newm->method_parameters_length() == method_parameters_len, "check");
1276   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1277   assert(newm->exception_table_length() == exception_table_len, "check");
1278   assert(newm->localvariable_table_length() == localvariable_len, "check");
1279   // Copy new byte codes
1280   memcpy(newm->code_base(), new_code, new_code_length);
1281   // Copy line number table
1282   if (new_compressed_linenumber_size > 0) {
1283     memcpy(newm->compressed_linenumber_table(),
1284            new_compressed_linenumber_table,
1285            new_compressed_linenumber_size);
1286   }
1287   // Copy method_parameters
1288   if (method_parameters_len > 0) {
1289     memcpy(newm->method_parameters_start(),
1290            m->method_parameters_start(),
1291            method_parameters_len * sizeof(MethodParametersElement));
1292   }
1293   // Copy checked_exceptions
1294   if (checked_exceptions_len > 0) {
1295     memcpy(newm->checked_exceptions_start(),
1296            m->checked_exceptions_start(),
1297            checked_exceptions_len * sizeof(CheckedExceptionElement));
1298   }
1299   // Copy exception table
1300   if (exception_table_len > 0) {
1301     memcpy(newm->exception_table_start(),
1302            m->exception_table_start(),
1303            exception_table_len * sizeof(ExceptionTableElement));
1304   }
1305   // Copy local variable number table
1306   if (localvariable_len > 0) {
1307     memcpy(newm->localvariable_table_start(),
1308            m->localvariable_table_start(),
1309            localvariable_len * sizeof(LocalVariableTableElement));
1310   }
1311   // Copy stackmap table
1312   if (m->has_stackmap_table()) {
1313     int code_attribute_length = m->stackmap_data()->length();
1314     Array<u1>* stackmap_data =
1315       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1316     memcpy((void*)stackmap_data->adr_at(0),
1317            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1318     newm->set_stackmap_data(stackmap_data);
1319   }
1320 
1321   // copy annotations over to new method
1322   newcm->copy_annotations_from(cm);
1323   return newm;
1324 }
1325 
1326 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1327   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1328   // because we are not loading from core libraries
1329   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1330   // which does not use the class default class loader so we check for its loader here
1331   const InstanceKlass* ik = InstanceKlass::cast(holder);
1332   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1333     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1334   }
1335 
1336   // see if the klass name is well-known:
1337   Symbol* klass_name = ik->name();
1338   return vmSymbols::find_sid(klass_name);
1339 }
1340 
1341 static bool is_unsafe_alias(vmSymbols::SID name_id) {
1342   // All 70 intrinsic candidate methods from sun.misc.Unsafe in 1.8.
1343   // Some have the same method name but different signature, e.g.
1344   // getByte(long), getByte(Object,long)
1345   switch (name_id) {
1346     case vmSymbols::VM_SYMBOL_ENUM_NAME(allocateInstance_name):
1347     case vmSymbols::VM_SYMBOL_ENUM_NAME(copyMemory_name):
1348     case vmSymbols::VM_SYMBOL_ENUM_NAME(loadFence_name):
1349     case vmSymbols::VM_SYMBOL_ENUM_NAME(storeFence_name):
1350     case vmSymbols::VM_SYMBOL_ENUM_NAME(fullFence_name):
1351     case vmSymbols::VM_SYMBOL_ENUM_NAME(getObject_name):
1352     case vmSymbols::VM_SYMBOL_ENUM_NAME(getBoolean_name):
1353     case vmSymbols::VM_SYMBOL_ENUM_NAME(getByte_name):
1354     case vmSymbols::VM_SYMBOL_ENUM_NAME(getShort_name):
1355     case vmSymbols::VM_SYMBOL_ENUM_NAME(getChar_name):
1356     case vmSymbols::VM_SYMBOL_ENUM_NAME(getInt_name):
1357     case vmSymbols::VM_SYMBOL_ENUM_NAME(getLong_name):
1358     case vmSymbols::VM_SYMBOL_ENUM_NAME(getFloat_name):
1359     case vmSymbols::VM_SYMBOL_ENUM_NAME(getDouble_name):
1360     case vmSymbols::VM_SYMBOL_ENUM_NAME(putObject_name):
1361     case vmSymbols::VM_SYMBOL_ENUM_NAME(putBoolean_name):
1362     case vmSymbols::VM_SYMBOL_ENUM_NAME(putByte_name):
1363     case vmSymbols::VM_SYMBOL_ENUM_NAME(putShort_name):
1364     case vmSymbols::VM_SYMBOL_ENUM_NAME(putChar_name):
1365     case vmSymbols::VM_SYMBOL_ENUM_NAME(putInt_name):
1366     case vmSymbols::VM_SYMBOL_ENUM_NAME(putLong_name):
1367     case vmSymbols::VM_SYMBOL_ENUM_NAME(putFloat_name):
1368     case vmSymbols::VM_SYMBOL_ENUM_NAME(putDouble_name):
1369     case vmSymbols::VM_SYMBOL_ENUM_NAME(getObjectVolatile_name):
1370     case vmSymbols::VM_SYMBOL_ENUM_NAME(getBooleanVolatile_name):
1371     case vmSymbols::VM_SYMBOL_ENUM_NAME(getByteVolatile_name):
1372     case vmSymbols::VM_SYMBOL_ENUM_NAME(getShortVolatile_name):
1373     case vmSymbols::VM_SYMBOL_ENUM_NAME(getCharVolatile_name):
1374     case vmSymbols::VM_SYMBOL_ENUM_NAME(getIntVolatile_name):
1375     case vmSymbols::VM_SYMBOL_ENUM_NAME(getLongVolatile_name):
1376     case vmSymbols::VM_SYMBOL_ENUM_NAME(getFloatVolatile_name):
1377     case vmSymbols::VM_SYMBOL_ENUM_NAME(getDoubleVolatile_name):
1378     case vmSymbols::VM_SYMBOL_ENUM_NAME(putObjectVolatile_name):
1379     case vmSymbols::VM_SYMBOL_ENUM_NAME(putBooleanVolatile_name):
1380     case vmSymbols::VM_SYMBOL_ENUM_NAME(putByteVolatile_name):
1381     case vmSymbols::VM_SYMBOL_ENUM_NAME(putShortVolatile_name):
1382     case vmSymbols::VM_SYMBOL_ENUM_NAME(putCharVolatile_name):
1383     case vmSymbols::VM_SYMBOL_ENUM_NAME(putIntVolatile_name):
1384     case vmSymbols::VM_SYMBOL_ENUM_NAME(putLongVolatile_name):
1385     case vmSymbols::VM_SYMBOL_ENUM_NAME(putFloatVolatile_name):
1386     case vmSymbols::VM_SYMBOL_ENUM_NAME(putDoubleVolatile_name):
1387     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAddress_name):
1388     case vmSymbols::VM_SYMBOL_ENUM_NAME(putAddress_name):
1389     case vmSymbols::VM_SYMBOL_ENUM_NAME(compareAndSwapObject_name):
1390     case vmSymbols::VM_SYMBOL_ENUM_NAME(compareAndSwapLong_name):
1391     case vmSymbols::VM_SYMBOL_ENUM_NAME(compareAndSwapInt_name):
1392     case vmSymbols::VM_SYMBOL_ENUM_NAME(putOrderedObject_name):
1393     case vmSymbols::VM_SYMBOL_ENUM_NAME(putOrderedLong_name):
1394     case vmSymbols::VM_SYMBOL_ENUM_NAME(putOrderedInt_name):
1395     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAndAddInt_name):
1396     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAndAddLong_name):
1397     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAndSetInt_name):
1398     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAndSetLong_name):
1399     case vmSymbols::VM_SYMBOL_ENUM_NAME(getAndSetObject_name):
1400     case vmSymbols::VM_SYMBOL_ENUM_NAME(park_name):
1401     case vmSymbols::VM_SYMBOL_ENUM_NAME(unpark_name):
1402       return true;
1403   }
1404 
1405   return false;
1406 }
1407 
1408 void Method::init_intrinsic_id() {
1409   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1410   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1411   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1412   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1413 
1414   // the klass name is well-known:
1415   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1416   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1417 
1418   // ditto for method and signature:
1419   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1420   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1421       && name_id == vmSymbols::NO_SID)
1422     return;
1423   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1424   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1425       && sig_id == vmSymbols::NO_SID)  return;
1426   jshort flags = access_flags().as_short();
1427 
1428   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1429   if (id != vmIntrinsics::_none) {
1430     set_intrinsic_id(id);
1431     if (id == vmIntrinsics::_Class_cast) {
1432       // Even if the intrinsic is rejected, we want to inline this simple method.
1433       set_force_inline(true);
1434     }
1435     return;
1436   }
1437 
1438   // A few slightly irregular cases:
1439   switch (klass_id) {
1440   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1441     // Second chance: check in regular Math.
1442     switch (name_id) {
1443     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1444     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1445     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1446       // pretend it is the corresponding method in the non-strict class:
1447       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1448       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1449       break;
1450     }
1451     break;
1452 
1453   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1454   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1455     if (!is_native())  break;
1456     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1457     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1458       id = vmIntrinsics::_none;
1459     break;
1460 
1461   case vmSymbols::VM_SYMBOL_ENUM_NAME(sun_misc_Unsafe):
1462     // Map sun.misc.Unsafe to jdk.internal.misc.Unsafe
1463     if (!is_unsafe_alias(name_id))  break;
1464     // pretend it is the corresponding method in the internal Unsafe class:
1465     klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(jdk_internal_misc_Unsafe);
1466     id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1467     break;
1468   }
1469 
1470   if (id != vmIntrinsics::_none) {
1471     // Set up its iid.  It is an alias method.
1472     set_intrinsic_id(id);
1473     return;
1474   }
1475 }
1476 
1477 // These two methods are static since a GC may move the Method
1478 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1479   if (!THREAD->can_call_java()) {
1480     // There is nothing useful this routine can do from within the Compile thread.
1481     // Hopefully, the signature contains only well-known classes.
1482     // We could scan for this and return true/false, but the caller won't care.
1483     return false;
1484   }
1485   bool sig_is_loaded = true;
1486   Handle class_loader(THREAD, m->method_holder()->class_loader());
1487   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1488   ResourceMark rm(THREAD);
1489   Symbol*  signature = m->signature();
1490   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1491     if (ss.is_object()) {
1492       Symbol* sym = ss.as_symbol(CHECK_(false));
1493       Symbol*  name  = sym;
1494       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1495                                              protection_domain, THREAD);
1496       // We are loading classes eagerly. If a ClassNotFoundException or
1497       // a LinkageError was generated, be sure to ignore it.
1498       if (HAS_PENDING_EXCEPTION) {
1499         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1500             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1501           CLEAR_PENDING_EXCEPTION;
1502         } else {
1503           return false;
1504         }
1505       }
1506       if( klass == NULL) { sig_is_loaded = false; }
1507     }
1508   }
1509   return sig_is_loaded;
1510 }
1511 
1512 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1513   Handle class_loader(THREAD, m->method_holder()->class_loader());
1514   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1515   ResourceMark rm(THREAD);
1516   Symbol*  signature = m->signature();
1517   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1518     if (ss.type() == T_OBJECT) {
1519       Symbol* name = ss.as_symbol_or_null();
1520       if (name == NULL) return true;
1521       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1522       if (klass == NULL) return true;
1523     }
1524   }
1525   return false;
1526 }
1527 
1528 // Exposed so field engineers can debug VM
1529 void Method::print_short_name(outputStream* st) {
1530   ResourceMark rm;
1531 #ifdef PRODUCT
1532   st->print(" %s::", method_holder()->external_name());
1533 #else
1534   st->print(" %s::", method_holder()->internal_name());
1535 #endif
1536   name()->print_symbol_on(st);
1537   if (WizardMode) signature()->print_symbol_on(st);
1538   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1539     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1540 }
1541 
1542 // Comparer for sorting an object array containing
1543 // Method*s.
1544 static int method_comparator(Method* a, Method* b) {
1545   return a->name()->fast_compare(b->name());
1546 }
1547 
1548 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1549 // default_methods also uses this without the ordering for fast find_method
1550 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1551   int length = methods->length();
1552   if (length > 1) {
1553     {
1554       NoSafepointVerifier nsv;
1555       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1556     }
1557     // Reset method ordering
1558     if (set_idnums) {
1559       for (int i = 0; i < length; i++) {
1560         Method* m = methods->at(i);
1561         m->set_method_idnum(i);
1562         m->set_orig_method_idnum(i);
1563       }
1564     }
1565   }
1566 }
1567 
1568 //-----------------------------------------------------------------------------------
1569 // Non-product code unless JVM/TI needs it
1570 
1571 #if !defined(PRODUCT) || INCLUDE_JVMTI
1572 class SignatureTypePrinter : public SignatureTypeNames {
1573  private:
1574   outputStream* _st;
1575   bool _use_separator;
1576 
1577   void type_name(const char* name) {
1578     if (_use_separator) _st->print(", ");
1579     _st->print("%s", name);
1580     _use_separator = true;
1581   }
1582 
1583  public:
1584   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1585     _st = st;
1586     _use_separator = false;
1587   }
1588 
1589   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1590   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1591 };
1592 
1593 
1594 void Method::print_name(outputStream* st) {
1595   Thread *thread = Thread::current();
1596   ResourceMark rm(thread);
1597   st->print("%s ", is_static() ? "static" : "virtual");
1598   if (WizardMode) {
1599     st->print("%s.", method_holder()->internal_name());
1600     name()->print_symbol_on(st);
1601     signature()->print_symbol_on(st);
1602   } else {
1603     SignatureTypePrinter sig(signature(), st);
1604     sig.print_returntype();
1605     st->print(" %s.", method_holder()->internal_name());
1606     name()->print_symbol_on(st);
1607     st->print("(");
1608     sig.print_parameters();
1609     st->print(")");
1610   }
1611 }
1612 #endif // !PRODUCT || INCLUDE_JVMTI
1613 
1614 
1615 void Method::print_codes_on(outputStream* st) const {
1616   print_codes_on(0, code_size(), st);
1617 }
1618 
1619 void Method::print_codes_on(int from, int to, outputStream* st) const {
1620   Thread *thread = Thread::current();
1621   ResourceMark rm(thread);
1622   methodHandle mh (thread, (Method*)this);
1623   BytecodeStream s(mh);
1624   s.set_interval(from, to);
1625   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1626   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1627 }
1628 
1629 
1630 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1631 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1632 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1633 // as end-of-stream terminator.
1634 
1635 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1636   // bci and line number does not compress into single byte.
1637   // Write out escape character and use regular compression for bci and line number.
1638   write_byte((jubyte)0xFF);
1639   write_signed_int(bci_delta);
1640   write_signed_int(line_delta);
1641 }
1642 
1643 // See comment in method.hpp which explains why this exists.
1644 #if defined(_M_AMD64) && _MSC_VER >= 1400
1645 #pragma optimize("", off)
1646 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1647   write_pair_inline(bci, line);
1648 }
1649 #pragma optimize("", on)
1650 #endif
1651 
1652 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1653   _bci = 0;
1654   _line = 0;
1655 };
1656 
1657 
1658 bool CompressedLineNumberReadStream::read_pair() {
1659   jubyte next = read_byte();
1660   // Check for terminator
1661   if (next == 0) return false;
1662   if (next == 0xFF) {
1663     // Escape character, regular compression used
1664     _bci  += read_signed_int();
1665     _line += read_signed_int();
1666   } else {
1667     // Single byte compression used
1668     _bci  += next >> 3;
1669     _line += next & 0x7;
1670   }
1671   return true;
1672 }
1673 
1674 
1675 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1676   BreakpointInfo* bp = method_holder()->breakpoints();
1677   for (; bp != NULL; bp = bp->next()) {
1678     if (bp->match(this, bci)) {
1679       return bp->orig_bytecode();
1680     }
1681   }
1682   {
1683     ResourceMark rm;
1684     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1685   }
1686   return Bytecodes::_shouldnotreachhere;
1687 }
1688 
1689 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1690   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1691   BreakpointInfo* bp = method_holder()->breakpoints();
1692   for (; bp != NULL; bp = bp->next()) {
1693     if (bp->match(this, bci)) {
1694       bp->set_orig_bytecode(code);
1695       // and continue, in case there is more than one
1696     }
1697   }
1698 }
1699 
1700 void Method::set_breakpoint(int bci) {
1701   InstanceKlass* ik = method_holder();
1702   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1703   bp->set_next(ik->breakpoints());
1704   ik->set_breakpoints(bp);
1705   // do this last:
1706   bp->set(this);
1707 }
1708 
1709 static void clear_matches(Method* m, int bci) {
1710   InstanceKlass* ik = m->method_holder();
1711   BreakpointInfo* prev_bp = NULL;
1712   BreakpointInfo* next_bp;
1713   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1714     next_bp = bp->next();
1715     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1716     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1717       // do this first:
1718       bp->clear(m);
1719       // unhook it
1720       if (prev_bp != NULL)
1721         prev_bp->set_next(next_bp);
1722       else
1723         ik->set_breakpoints(next_bp);
1724       delete bp;
1725       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1726       // at same location. So we have multiple matching (method_index and bci)
1727       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1728       // breakpoint for clear_breakpoint request and keep all other method versions
1729       // BreakpointInfo for future clear_breakpoint request.
1730       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1731       // which is being called when class is unloaded. We delete all the Breakpoint
1732       // information for all versions of method. We may not correctly restore the original
1733       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1734       // so these methods won't be used anymore.
1735       if (bci >= 0) {
1736         break;
1737       }
1738     } else {
1739       // This one is a keeper.
1740       prev_bp = bp;
1741     }
1742   }
1743 }
1744 
1745 void Method::clear_breakpoint(int bci) {
1746   assert(bci >= 0, "");
1747   clear_matches(this, bci);
1748 }
1749 
1750 void Method::clear_all_breakpoints() {
1751   clear_matches(this, -1);
1752 }
1753 
1754 
1755 int Method::invocation_count() {
1756   MethodCounters *mcs = method_counters();
1757   if (TieredCompilation) {
1758     MethodData* const mdo = method_data();
1759     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1760         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1761       return InvocationCounter::count_limit;
1762     } else {
1763       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1764              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1765     }
1766   } else {
1767     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1768   }
1769 }
1770 
1771 int Method::backedge_count() {
1772   MethodCounters *mcs = method_counters();
1773   if (TieredCompilation) {
1774     MethodData* const mdo = method_data();
1775     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1776         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1777       return InvocationCounter::count_limit;
1778     } else {
1779       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1780              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1781     }
1782   } else {
1783     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1784   }
1785 }
1786 
1787 int Method::highest_comp_level() const {
1788   const MethodCounters* mcs = method_counters();
1789   if (mcs != NULL) {
1790     return mcs->highest_comp_level();
1791   } else {
1792     return CompLevel_none;
1793   }
1794 }
1795 
1796 int Method::highest_osr_comp_level() const {
1797   const MethodCounters* mcs = method_counters();
1798   if (mcs != NULL) {
1799     return mcs->highest_osr_comp_level();
1800   } else {
1801     return CompLevel_none;
1802   }
1803 }
1804 
1805 void Method::set_highest_comp_level(int level) {
1806   MethodCounters* mcs = method_counters();
1807   if (mcs != NULL) {
1808     mcs->set_highest_comp_level(level);
1809   }
1810 }
1811 
1812 void Method::set_highest_osr_comp_level(int level) {
1813   MethodCounters* mcs = method_counters();
1814   if (mcs != NULL) {
1815     mcs->set_highest_osr_comp_level(level);
1816   }
1817 }
1818 
1819 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1820   _bci = bci;
1821   _name_index = m->name_index();
1822   _signature_index = m->signature_index();
1823   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1824   if (_orig_bytecode == Bytecodes::_breakpoint)
1825     _orig_bytecode = m->orig_bytecode_at(_bci);
1826   _next = NULL;
1827 }
1828 
1829 void BreakpointInfo::set(Method* method) {
1830 #ifdef ASSERT
1831   {
1832     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1833     if (code == Bytecodes::_breakpoint)
1834       code = method->orig_bytecode_at(_bci);
1835     assert(orig_bytecode() == code, "original bytecode must be the same");
1836   }
1837 #endif
1838   Thread *thread = Thread::current();
1839   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1840   method->incr_number_of_breakpoints(thread);
1841   SystemDictionary::notice_modification();
1842   {
1843     // Deoptimize all dependents on this method
1844     HandleMark hm(thread);
1845     methodHandle mh(thread, method);
1846     CodeCache::flush_dependents_on_method(mh);
1847   }
1848 }
1849 
1850 void BreakpointInfo::clear(Method* method) {
1851   *method->bcp_from(_bci) = orig_bytecode();
1852   assert(method->number_of_breakpoints() > 0, "must not go negative");
1853   method->decr_number_of_breakpoints(Thread::current());
1854 }
1855 
1856 // jmethodID handling
1857 
1858 // This is a block allocating object, sort of like JNIHandleBlock, only a
1859 // lot simpler.
1860 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1861 // never get rid of it.
1862 
1863 static const int min_block_size = 8;
1864 
1865 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1866   friend class JNIMethodBlock;
1867   Method**        _methods;
1868   int             _number_of_methods;
1869   int             _top;
1870   JNIMethodBlockNode* _next;
1871 
1872  public:
1873 
1874   JNIMethodBlockNode(int num_methods = min_block_size);
1875 
1876   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1877 
1878   void ensure_methods(int num_addl_methods) {
1879     if (_top < _number_of_methods) {
1880       num_addl_methods -= _number_of_methods - _top;
1881       if (num_addl_methods <= 0) {
1882         return;
1883       }
1884     }
1885     if (_next == NULL) {
1886       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1887     } else {
1888       _next->ensure_methods(num_addl_methods);
1889     }
1890   }
1891 };
1892 
1893 class JNIMethodBlock : public CHeapObj<mtClass> {
1894   JNIMethodBlockNode _head;
1895   JNIMethodBlockNode *_last_free;
1896  public:
1897   static Method* const _free_method;
1898 
1899   JNIMethodBlock(int initial_capacity = min_block_size)
1900       : _head(initial_capacity), _last_free(&_head) {}
1901 
1902   void ensure_methods(int num_addl_methods) {
1903     _last_free->ensure_methods(num_addl_methods);
1904   }
1905 
1906   Method** add_method(Method* m) {
1907     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1908       if (b->_top < b->_number_of_methods) {
1909         // top points to the next free entry.
1910         int i = b->_top;
1911         b->_methods[i] = m;
1912         b->_top++;
1913         _last_free = b;
1914         return &(b->_methods[i]);
1915       } else if (b->_top == b->_number_of_methods) {
1916         // if the next free entry ran off the block see if there's a free entry
1917         for (int i = 0; i < b->_number_of_methods; i++) {
1918           if (b->_methods[i] == _free_method) {
1919             b->_methods[i] = m;
1920             _last_free = b;
1921             return &(b->_methods[i]);
1922           }
1923         }
1924         // Only check each block once for frees.  They're very unlikely.
1925         // Increment top past the end of the block.
1926         b->_top++;
1927       }
1928       // need to allocate a next block.
1929       if (b->_next == NULL) {
1930         b->_next = _last_free = new JNIMethodBlockNode();
1931       }
1932     }
1933     guarantee(false, "Should always allocate a free block");
1934     return NULL;
1935   }
1936 
1937   bool contains(Method** m) {
1938     if (m == NULL) return false;
1939     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1940       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
1941         // This is a bit of extra checking, for two reasons.  One is
1942         // that contains() deals with pointers that are passed in by
1943         // JNI code, so making sure that the pointer is aligned
1944         // correctly is valuable.  The other is that <= and > are
1945         // technically not defined on pointers, so the if guard can
1946         // pass spuriously; no modern compiler is likely to make that
1947         // a problem, though (and if one did, the guard could also
1948         // fail spuriously, which would be bad).
1949         ptrdiff_t idx = m - b->_methods;
1950         if (b->_methods + idx == m) {
1951           return true;
1952         }
1953       }
1954     }
1955     return false;  // not found
1956   }
1957 
1958   // Doesn't really destroy it, just marks it as free so it can be reused.
1959   void destroy_method(Method** m) {
1960 #ifdef ASSERT
1961     assert(contains(m), "should be a methodID");
1962 #endif // ASSERT
1963     *m = _free_method;
1964   }
1965 
1966   // During class unloading the methods are cleared, which is different
1967   // than freed.
1968   void clear_all_methods() {
1969     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1970       for (int i = 0; i< b->_number_of_methods; i++) {
1971         b->_methods[i] = NULL;
1972       }
1973     }
1974   }
1975 #ifndef PRODUCT
1976   int count_methods() {
1977     // count all allocated methods
1978     int count = 0;
1979     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1980       for (int i = 0; i< b->_number_of_methods; i++) {
1981         if (b->_methods[i] != _free_method) count++;
1982       }
1983     }
1984     return count;
1985   }
1986 #endif // PRODUCT
1987 };
1988 
1989 // Something that can't be mistaken for an address or a markOop
1990 Method* const JNIMethodBlock::_free_method = (Method*)55;
1991 
1992 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
1993   _number_of_methods = MAX2(num_methods, min_block_size);
1994   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
1995   for (int i = 0; i < _number_of_methods; i++) {
1996     _methods[i] = JNIMethodBlock::_free_method;
1997   }
1998 }
1999 
2000 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2001   ClassLoaderData* cld = loader_data;
2002   if (!SafepointSynchronize::is_at_safepoint()) {
2003     // Have to add jmethod_ids() to class loader data thread-safely.
2004     // Also have to add the method to the list safely, which the cld lock
2005     // protects as well.
2006     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2007     if (cld->jmethod_ids() == NULL) {
2008       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2009     } else {
2010       cld->jmethod_ids()->ensure_methods(capacity);
2011     }
2012   } else {
2013     // At safepoint, we are single threaded and can set this.
2014     if (cld->jmethod_ids() == NULL) {
2015       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2016     } else {
2017       cld->jmethod_ids()->ensure_methods(capacity);
2018     }
2019   }
2020 }
2021 
2022 // Add a method id to the jmethod_ids
2023 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2024   ClassLoaderData* cld = loader_data;
2025 
2026   if (!SafepointSynchronize::is_at_safepoint()) {
2027     // Have to add jmethod_ids() to class loader data thread-safely.
2028     // Also have to add the method to the list safely, which the cld lock
2029     // protects as well.
2030     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2031     if (cld->jmethod_ids() == NULL) {
2032       cld->set_jmethod_ids(new JNIMethodBlock());
2033     }
2034     // jmethodID is a pointer to Method*
2035     return (jmethodID)cld->jmethod_ids()->add_method(m);
2036   } else {
2037     // At safepoint, we are single threaded and can set this.
2038     if (cld->jmethod_ids() == NULL) {
2039       cld->set_jmethod_ids(new JNIMethodBlock());
2040     }
2041     // jmethodID is a pointer to Method*
2042     return (jmethodID)cld->jmethod_ids()->add_method(m);
2043   }
2044 }
2045 
2046 // Mark a jmethodID as free.  This is called when there is a data race in
2047 // InstanceKlass while creating the jmethodID cache.
2048 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2049   ClassLoaderData* cld = loader_data;
2050   Method** ptr = (Method**)m;
2051   assert(cld->jmethod_ids() != NULL, "should have method handles");
2052   cld->jmethod_ids()->destroy_method(ptr);
2053 }
2054 
2055 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2056   // Can't assert the method_holder is the same because the new method has the
2057   // scratch method holder.
2058   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2059            == new_method->method_holder()->class_loader(),
2060          "changing to a different class loader");
2061   // Just change the method in place, jmethodID pointer doesn't change.
2062   *((Method**)jmid) = new_method;
2063 }
2064 
2065 bool Method::is_method_id(jmethodID mid) {
2066   Method* m = resolve_jmethod_id(mid);
2067   assert(m != NULL, "should be called with non-null method");
2068   InstanceKlass* ik = m->method_holder();
2069   ClassLoaderData* cld = ik->class_loader_data();
2070   if (cld->jmethod_ids() == NULL) return false;
2071   return (cld->jmethod_ids()->contains((Method**)mid));
2072 }
2073 
2074 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2075   if (mid == NULL) return NULL;
2076   Method* o = resolve_jmethod_id(mid);
2077   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2078     return NULL;
2079   }
2080   return o;
2081 };
2082 
2083 void Method::set_on_stack(const bool value) {
2084   // Set both the method itself and its constant pool.  The constant pool
2085   // on stack means some method referring to it is also on the stack.
2086   constants()->set_on_stack(value);
2087 
2088   bool already_set = on_stack();
2089   _access_flags.set_on_stack(value);
2090   if (value && !already_set) {
2091     MetadataOnStackMark::record(this);
2092   }
2093 }
2094 
2095 // Called when the class loader is unloaded to make all methods weak.
2096 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2097   loader_data->jmethod_ids()->clear_all_methods();
2098 }
2099 
2100 bool Method::has_method_vptr(const void* ptr) {
2101   Method m;
2102   // This assumes that the vtbl pointer is the first word of a C++ object.
2103   // This assumption is also in universe.cpp patch_klass_vtble
2104   return dereference_vptr(&m) == dereference_vptr(ptr);
2105 }
2106 
2107 // Check that this pointer is valid by checking that the vtbl pointer matches
2108 bool Method::is_valid_method() const {
2109   if (this == NULL) {
2110     return false;
2111   } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2112     // Quick sanity check on pointer.
2113     return false;
2114   } else if (!is_metaspace_object()) {
2115     return false;
2116   } else {
2117     return has_method_vptr((const void*)this);
2118   }
2119 }
2120 
2121 #ifndef PRODUCT
2122 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2123   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2124 }
2125 #endif // PRODUCT
2126 
2127 
2128 // Printing
2129 
2130 #ifndef PRODUCT
2131 
2132 void Method::print_on(outputStream* st) const {
2133   ResourceMark rm;
2134   assert(is_method(), "must be method");
2135   st->print_cr("%s", internal_name());
2136   // get the effect of PrintOopAddress, always, for methods:
2137   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2138   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2139   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2140   constants()->print_value_on(st); st->cr();
2141   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2142   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2143   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2144   st->print_cr(" - max stack:         %d",   max_stack());
2145   st->print_cr(" - max locals:        %d",   max_locals());
2146   st->print_cr(" - size of params:    %d",   size_of_parameters());
2147   st->print_cr(" - method size:       %d",   method_size());
2148   if (intrinsic_id() != vmIntrinsics::_none)
2149     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2150   if (highest_comp_level() != CompLevel_none)
2151     st->print_cr(" - highest level:     %d", highest_comp_level());
2152   st->print_cr(" - vtable index:      %d",   _vtable_index);
2153   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2154   st->print(   " - adapters:          ");
2155   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2156   if (a == NULL)
2157     st->print_cr(INTPTR_FORMAT, p2i(a));
2158   else
2159     a->print_adapter_on(st);
2160   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2161   st->print_cr(" - code size:         %d",   code_size());
2162   if (code_size() != 0) {
2163     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2164     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2165   }
2166   if (method_data() != NULL) {
2167     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2168   }
2169   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2170   if (checked_exceptions_length() > 0) {
2171     CheckedExceptionElement* table = checked_exceptions_start();
2172     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2173     if (Verbose) {
2174       for (int i = 0; i < checked_exceptions_length(); i++) {
2175         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2176       }
2177     }
2178   }
2179   if (has_linenumber_table()) {
2180     u_char* table = compressed_linenumber_table();
2181     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2182     if (Verbose) {
2183       CompressedLineNumberReadStream stream(table);
2184       while (stream.read_pair()) {
2185         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2186       }
2187     }
2188   }
2189   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2190   if (localvariable_table_length() > 0) {
2191     LocalVariableTableElement* table = localvariable_table_start();
2192     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2193     if (Verbose) {
2194       for (int i = 0; i < localvariable_table_length(); i++) {
2195         int bci = table[i].start_bci;
2196         int len = table[i].length;
2197         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2198         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2199         int slot = table[i].slot;
2200         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2201       }
2202     }
2203   }
2204   if (code() != NULL) {
2205     st->print   (" - compiled code: ");
2206     code()->print_value_on(st);
2207   }
2208   if (is_native()) {
2209     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2210     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2211   }
2212 }
2213 
2214 void Method::print_linkage_flags(outputStream* st) {
2215   access_flags().print_on(st);
2216   if (is_default_method()) {
2217     st->print("default ");
2218   }
2219   if (is_overpass()) {
2220     st->print("overpass ");
2221   }
2222 }
2223 #endif //PRODUCT
2224 
2225 void Method::print_value_on(outputStream* st) const {
2226   assert(is_method(), "must be method");
2227   st->print("%s", internal_name());
2228   print_address_on(st);
2229   st->print(" ");
2230   name()->print_value_on(st);
2231   st->print(" ");
2232   signature()->print_value_on(st);
2233   st->print(" in ");
2234   method_holder()->print_value_on(st);
2235   if (WizardMode) st->print("#%d", _vtable_index);
2236   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2237   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2238 }
2239 
2240 #if INCLUDE_SERVICES
2241 // Size Statistics
2242 void Method::collect_statistics(KlassSizeStats *sz) const {
2243   int mysize = sz->count(this);
2244   sz->_method_bytes += mysize;
2245   sz->_method_all_bytes += mysize;
2246   sz->_rw_bytes += mysize;
2247 
2248   if (constMethod()) {
2249     constMethod()->collect_statistics(sz);
2250   }
2251   if (method_data()) {
2252     method_data()->collect_statistics(sz);
2253   }
2254 }
2255 #endif // INCLUDE_SERVICES
2256 
2257 // LogTouchedMethods and PrintTouchedMethods
2258 
2259 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2260 // the Method may be garbage collected. Let's roll our own hash table.
2261 class TouchedMethodRecord : CHeapObj<mtTracing> {
2262 public:
2263   // It's OK to store Symbols here because they will NOT be GC'ed if
2264   // LogTouchedMethods is enabled.
2265   TouchedMethodRecord* _next;
2266   Symbol* _class_name;
2267   Symbol* _method_name;
2268   Symbol* _method_signature;
2269 };
2270 
2271 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2272 static TouchedMethodRecord** _touched_method_table = NULL;
2273 
2274 void Method::log_touched(TRAPS) {
2275 
2276   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2277   Symbol* my_class = klass_name();
2278   Symbol* my_name  = name();
2279   Symbol* my_sig   = signature();
2280 
2281   unsigned int hash = my_class->identity_hash() +
2282                       my_name->identity_hash() +
2283                       my_sig->identity_hash();
2284   juint index = juint(hash) % table_size;
2285 
2286   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2287   if (_touched_method_table == NULL) {
2288     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2289                                               mtTracing, CURRENT_PC);
2290     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2291   }
2292 
2293   TouchedMethodRecord* ptr = _touched_method_table[index];
2294   while (ptr) {
2295     if (ptr->_class_name       == my_class &&
2296         ptr->_method_name      == my_name &&
2297         ptr->_method_signature == my_sig) {
2298       return;
2299     }
2300     if (ptr->_next == NULL) break;
2301     ptr = ptr->_next;
2302   }
2303   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2304   my_class->set_permanent();  // prevent reclaimed by GC
2305   my_name->set_permanent();
2306   my_sig->set_permanent();
2307   nptr->_class_name         = my_class;
2308   nptr->_method_name        = my_name;
2309   nptr->_method_signature   = my_sig;
2310   nptr->_next               = NULL;
2311 
2312   if (ptr == NULL) {
2313     // first
2314     _touched_method_table[index] = nptr;
2315   } else {
2316     ptr->_next = nptr;
2317   }
2318 }
2319 
2320 void Method::print_touched_methods(outputStream* out) {
2321   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2322   out->print_cr("# Method::print_touched_methods version 1");
2323   if (_touched_method_table) {
2324     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2325       TouchedMethodRecord* ptr = _touched_method_table[i];
2326       while(ptr) {
2327         ptr->_class_name->print_symbol_on(out);       out->print(".");
2328         ptr->_method_name->print_symbol_on(out);      out->print(":");
2329         ptr->_method_signature->print_symbol_on(out); out->cr();
2330         ptr = ptr->_next;
2331       }
2332     }
2333   }
2334 }
2335 
2336 // Verification
2337 
2338 void Method::verify_on(outputStream* st) {
2339   guarantee(is_method(), "object must be method");
2340   guarantee(constants()->is_constantPool(), "should be constant pool");
2341   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2342   MethodData* md = method_data();
2343   guarantee(md == NULL ||
2344       md->is_methodData(), "should be method data");
2345 }