1 /*
   2  * Copyright (c) 1997, 2018, 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 "interpreter/bytecodeStream.hpp"
  32 #include "interpreter/bytecodeTracer.hpp"
  33 #include "interpreter/bytecodes.hpp"
  34 #include "interpreter/interpreter.hpp"
  35 #include "interpreter/oopMapCache.hpp"
  36 #include "memory/allocation.inline.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/metaspaceClosure.hpp"
  40 #include "memory/metaspaceShared.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "oops/constMethod.hpp"
  44 #include "oops/method.inline.hpp"
  45 #include "oops/methodData.hpp"
  46 #include "oops/objArrayOop.inline.hpp"
  47 #include "oops/oop.inline.hpp"
  48 #include "oops/symbol.hpp"
  49 #include "oops/valueKlass.hpp"
  50 #include "prims/jvmtiExport.hpp"
  51 #include "prims/methodHandles.hpp"
  52 #include "prims/nativeLookup.hpp"
  53 #include "runtime/arguments.hpp"
  54 #include "runtime/compilationPolicy.hpp"
  55 #include "runtime/frame.inline.hpp"
  56 #include "runtime/handles.inline.hpp"
  57 #include "runtime/init.hpp"
  58 #include "runtime/orderAccess.hpp"
  59 #include "runtime/relocator.hpp"
  60 #include "runtime/safepointVerifiers.hpp"
  61 #include "runtime/sharedRuntime.hpp"
  62 #include "runtime/signature.hpp"
  63 #include "utilities/align.hpp"
  64 #include "utilities/quickSort.hpp"
  65 #include "utilities/vmError.hpp"
  66 #include "utilities/xmlstream.hpp"
  67 
  68 // Implementation of Method
  69 
  70 Method* Method::allocate(ClassLoaderData* loader_data,
  71                          int byte_code_size,
  72                          AccessFlags access_flags,
  73                          InlineTableSizes* sizes,
  74                          ConstMethod::MethodType method_type,
  75                          TRAPS) {
  76   assert(!access_flags.is_native() || byte_code_size == 0,
  77          "native methods should not contain byte codes");
  78   ConstMethod* cm = ConstMethod::allocate(loader_data,
  79                                           byte_code_size,
  80                                           sizes,
  81                                           method_type,
  82                                           CHECK_NULL);
  83   int size = Method::size(access_flags.is_native());
  84   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  85 }
  86 
  87 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  88   NoSafepointVerifier no_safepoint;
  89   set_constMethod(xconst);
  90   set_access_flags(access_flags);
  91   set_intrinsic_id(vmIntrinsics::_none);
  92   set_force_inline(false);
  93   set_hidden(false);
  94   set_dont_inline(false);
  95   set_has_injected_profile(false);
  96   set_method_data(NULL);
  97   clear_method_counters();
  98   set_vtable_index(Method::garbage_vtable_index);
  99 
 100   // Fix and bury in Method*
 101   set_interpreter_entry(NULL); // sets i2i entry and from_int
 102   set_adapter_entry(NULL);
 103   clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
 104 
 105   if (access_flags.is_native()) {
 106     clear_native_function();
 107     set_signature_handler(NULL);
 108   }
 109   NOT_PRODUCT(set_compiled_invocation_count(0);)
 110 }
 111 
 112 // Release Method*.  The nmethod will be gone when we get here because
 113 // we've walked the code cache.
 114 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 115   MetadataFactory::free_metadata(loader_data, constMethod());
 116   set_constMethod(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_data());
 118   set_method_data(NULL);
 119   MetadataFactory::free_metadata(loader_data, method_counters());
 120   clear_method_counters();
 121   // The nmethod will be gone when we get here.
 122   if (code() != NULL) _code = NULL;
 123 }
 124 
 125 address Method::get_i2c_entry() {
 126   assert(adapter() != NULL, "must have");
 127   return adapter()->get_i2c_entry();
 128 }
 129 
 130 address Method::get_c2i_entry() {
 131   assert(adapter() != NULL, "must have");
 132   return adapter()->get_c2i_entry();
 133 }
 134 
 135 address Method::get_c2i_unverified_entry() {
 136   assert(adapter() != NULL, "must have");
 137   return adapter()->get_c2i_unverified_entry();
 138 }
 139 
 140 char* Method::name_and_sig_as_C_string() const {
 141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 149   const char* klass_name = klass->external_name();
 150   int klass_name_len  = (int)strlen(klass_name);
 151   int method_name_len = method_name->utf8_length();
 152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 154   strcpy(dest, klass_name);
 155   dest[klass_name_len] = '.';
 156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 158   dest[len] = 0;
 159   return dest;
 160 }
 161 
 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 163   Symbol* klass_name = klass->name();
 164   klass_name->as_klass_external_name(buf, size);
 165   int len = (int)strlen(buf);
 166 
 167   if (len < size - 1) {
 168     buf[len++] = '.';
 169 
 170     method_name->as_C_string(&(buf[len]), size - len);
 171     len = (int)strlen(buf);
 172 
 173     signature->as_C_string(&(buf[len]), size - len);
 174   }
 175 
 176   return buf;
 177 }
 178 
 179 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 181   // access exception table
 182   ExceptionTable table(mh());
 183   int length = table.length();
 184   // iterate through all entries sequentially
 185   constantPoolHandle pool(THREAD, mh->constants());
 186   for (int i = 0; i < length; i ++) {
 187     //reacquire the table in case a GC happened
 188     ExceptionTable table(mh());
 189     int beg_bci = table.start_pc(i);
 190     int end_bci = table.end_pc(i);
 191     assert(beg_bci <= end_bci, "inconsistent exception table");
 192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 193       // exception handler bci range covers throw_bci => investigate further
 194       int handler_bci = table.handler_pc(i);
 195       int klass_index = table.catch_type_index(i);
 196       if (klass_index == 0) {
 197         return handler_bci;
 198       } else if (ex_klass == NULL) {
 199         return handler_bci;
 200       } else {
 201         // we know the exception class => get the constraint class
 202         // this may require loading of the constraint class; if verification
 203         // fails or some other exception occurs, return handler_bci
 204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 205         assert(k != NULL, "klass not loaded");
 206         if (ex_klass->is_subtype_of(k)) {
 207           return handler_bci;
 208         }
 209       }
 210     }
 211   }
 212 
 213   return -1;
 214 }
 215 
 216 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 217   methodHandle h_this(Thread::current(), this);
 218   // Only GC uses the OopMapCache during thread stack root scanning
 219   // any other uses generate an oopmap but do not save it in the cache.
 220   if (Universe::heap()->is_gc_active()) {
 221     method_holder()->mask_for(h_this, bci, mask);
 222   } else {
 223     OopMapCache::compute_one_oop_map(h_this, bci, mask);
 224   }
 225   return;
 226 }
 227 
 228 
 229 int Method::bci_from(address bcp) const {
 230   if (is_native() && bcp == 0) {
 231     return 0;
 232   }
 233 #ifdef ASSERT
 234   {
 235     ResourceMark rm;
 236     assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
 237            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 238            p2i(bcp), name_and_sig_as_C_string());
 239   }
 240 #endif
 241   return bcp - code_base();
 242 }
 243 
 244 
 245 int Method::validate_bci(int bci) const {
 246   return (bci == 0 || bci < code_size()) ? bci : -1;
 247 }
 248 
 249 // Return bci if it appears to be a valid bcp
 250 // Return -1 otherwise.
 251 // Used by profiling code, when invalid data is a possibility.
 252 // The caller is responsible for validating the Method* itself.
 253 int Method::validate_bci_from_bcp(address bcp) const {
 254   // keep bci as -1 if not a valid bci
 255   int bci = -1;
 256   if (bcp == 0 || bcp == code_base()) {
 257     // code_size() may return 0 and we allow 0 here
 258     // the method may be native
 259     bci = 0;
 260   } else if (contains(bcp)) {
 261     bci = bcp - code_base();
 262   }
 263   // Assert that if we have dodged any asserts, bci is negative.
 264   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 265   return bci;
 266 }
 267 
 268 address Method::bcp_from(int bci) const {
 269   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 270          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 271   address bcp = code_base() + bci;
 272   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 273   return bcp;
 274 }
 275 
 276 address Method::bcp_from(address bcp) const {
 277   if (is_native() && bcp == NULL) {
 278     return code_base();
 279   } else {
 280     return bcp;
 281   }
 282 }
 283 
 284 int Method::size(bool is_native) {
 285   // If native, then include pointers for native_function and signature_handler
 286   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 287   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 288   return align_metadata_size(header_size() + extra_words);
 289 }
 290 
 291 
 292 Symbol* Method::klass_name() const {
 293   return method_holder()->name();
 294 }
 295 
 296 
 297 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 298   log_trace(cds)("Iter(Method): %p", this);
 299 
 300   it->push(&_constMethod);
 301   it->push(&_method_data);
 302   it->push(&_method_counters);
 303 }
 304 
 305 // Attempt to return method oop to original state.  Clear any pointers
 306 // (to objects outside the shared spaces).  We won't be able to predict
 307 // where they should point in a new JVM.  Further initialize some
 308 // entries now in order allow them to be write protected later.
 309 
 310 void Method::remove_unshareable_info() {
 311   unlink_method();
 312 }
 313 
 314 void Method::set_vtable_index(int index) {
 315   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 316     // At runtime initialize_vtable is rerun as part of link_class_impl()
 317     // for a shared class loaded by the non-boot loader to obtain the loader
 318     // constraints based on the runtime classloaders' context.
 319     return; // don't write into the shared class
 320   } else {
 321     _vtable_index = index;
 322   }
 323 }
 324 
 325 void Method::set_itable_index(int index) {
 326   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 327     // At runtime initialize_itable is rerun as part of link_class_impl()
 328     // for a shared class loaded by the non-boot loader to obtain the loader
 329     // constraints based on the runtime classloaders' context. The dumptime
 330     // itable index should be the same as the runtime index.
 331     assert(_vtable_index == itable_index_max - index,
 332            "archived itable index is different from runtime index");
 333     return; // don’t write into the shared class
 334   } else {
 335     _vtable_index = itable_index_max - index;
 336   }
 337   assert(valid_itable_index(), "");
 338 }
 339 
 340 
 341 
 342 bool Method::was_executed_more_than(int n) {
 343   // Invocation counter is reset when the Method* is compiled.
 344   // If the method has compiled code we therefore assume it has
 345   // be excuted more than n times.
 346   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 347     // interpreter doesn't bump invocation counter of trivial methods
 348     // compiler does not bump invocation counter of compiled methods
 349     return true;
 350   }
 351   else if ((method_counters() != NULL &&
 352             method_counters()->invocation_counter()->carry()) ||
 353            (method_data() != NULL &&
 354             method_data()->invocation_counter()->carry())) {
 355     // The carry bit is set when the counter overflows and causes
 356     // a compilation to occur.  We don't know how many times
 357     // the counter has been reset, so we simply assume it has
 358     // been executed more than n times.
 359     return true;
 360   } else {
 361     return invocation_count() > n;
 362   }
 363 }
 364 
 365 void Method::print_invocation_count() {
 366   if (is_static()) tty->print("static ");
 367   if (is_final()) tty->print("final ");
 368   if (is_synchronized()) tty->print("synchronized ");
 369   if (is_native()) tty->print("native ");
 370   tty->print("%s::", method_holder()->external_name());
 371   name()->print_symbol_on(tty);
 372   signature()->print_symbol_on(tty);
 373 
 374   if (WizardMode) {
 375     // dump the size of the byte codes
 376     tty->print(" {%d}", code_size());
 377   }
 378   tty->cr();
 379 
 380   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 381   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 382   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 383 #ifndef PRODUCT
 384   if (CountCompiledCalls) {
 385     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 386   }
 387 #endif
 388 }
 389 
 390 // Build a MethodData* object to hold information about this method
 391 // collected in the interpreter.
 392 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 393   // Do not profile the method if metaspace has hit an OOM previously
 394   // allocating profiling data. Callers clear pending exception so don't
 395   // add one here.
 396   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 397     return;
 398   }
 399 
 400   // Grab a lock here to prevent multiple
 401   // MethodData*s from being created.
 402   MutexLocker ml(MethodData_lock, THREAD);
 403   if (method->method_data() == NULL) {
 404     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 405     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 406     if (HAS_PENDING_EXCEPTION) {
 407       CompileBroker::log_metaspace_failure();
 408       ClassLoaderDataGraph::set_metaspace_oom(true);
 409       return;   // return the exception (which is cleared)
 410     }
 411 
 412     method->set_method_data(method_data);
 413     if (PrintMethodData && (Verbose || WizardMode)) {
 414       ResourceMark rm(THREAD);
 415       tty->print("build_interpreter_method_data for ");
 416       method->print_name(tty);
 417       tty->cr();
 418       // At the end of the run, the MDO, full of data, will be dumped.
 419     }
 420   }
 421 }
 422 
 423 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 424   // Do not profile the method if metaspace has hit an OOM previously
 425   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 426     return NULL;
 427   }
 428 
 429   methodHandle mh(m);
 430   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 431   if (HAS_PENDING_EXCEPTION) {
 432     CompileBroker::log_metaspace_failure();
 433     ClassLoaderDataGraph::set_metaspace_oom(true);
 434     return NULL;   // return the exception (which is cleared)
 435   }
 436   if (!mh->init_method_counters(counters)) {
 437     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 438   }
 439 
 440   if (LogTouchedMethods) {
 441     mh->log_touched(CHECK_NULL);
 442   }
 443 
 444   return mh->method_counters();
 445 }
 446 
 447 bool Method::init_method_counters(MethodCounters* counters) {
 448   // Try to install a pointer to MethodCounters, return true on success.
 449   return Atomic::replace_if_null(counters, &_method_counters);
 450 }
 451 
 452 int Method::extra_stack_words() {
 453   // not an inline function, to avoid a header dependency on Interpreter
 454   return extra_stack_entries() * Interpreter::stackElementSize;
 455 }
 456 
 457 
 458 void Method::compute_size_of_parameters(Thread *thread) {
 459   ArgumentSizeComputer asc(signature());
 460   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 461 }
 462 
 463 BasicType Method::result_type() const {
 464   ResultTypeFinder rtf(signature());
 465   return rtf.type();
 466 }
 467 
 468 #ifdef ASSERT
 469 // ValueKlass the method is declared to return. This must not
 470 // safepoint as it is called with references live on the stack at
 471 // locations the GC is unaware of.
 472 ValueKlass* Method::returned_value_type(Thread* thread) const {
 473   assert(is_returning_vt(), "method return type should be value type");
 474   SignatureStream ss(signature());
 475   while (!ss.at_return_type()) {
 476     ss.next();
 477   }
 478   Handle class_loader(thread, method_holder()->class_loader());
 479   Handle protection_domain(thread, method_holder()->protection_domain());
 480   Klass* k = NULL;
 481   {
 482     NoSafepointVerifier nsv;
 483     k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
 484   }
 485   assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
 486   return ValueKlass::cast(k);
 487 }
 488 #endif
 489 
 490 bool Method::has_value_args() const {
 491   return adapter()->get_sig_extended() != NULL;
 492 }
 493 
 494 bool Method::is_empty_method() const {
 495   return  code_size() == 1
 496       && *code_base() == Bytecodes::_return;
 497 }
 498 
 499 
 500 bool Method::is_vanilla_constructor() const {
 501   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 502   // which only calls the superclass vanilla constructor and possibly does stores of
 503   // zero constants to local fields:
 504   //
 505   //   aload_0
 506   //   invokespecial
 507   //   indexbyte1
 508   //   indexbyte2
 509   //
 510   // followed by an (optional) sequence of:
 511   //
 512   //   aload_0
 513   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 514   //   putfield
 515   //   indexbyte1
 516   //   indexbyte2
 517   //
 518   // followed by:
 519   //
 520   //   return
 521 
 522   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 523   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 524   int size = code_size();
 525   // Check if size match
 526   if (size == 0 || size % 5 != 0) return false;
 527   address cb = code_base();
 528   int last = size - 1;
 529   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 530     // Does not call superclass default constructor
 531     return false;
 532   }
 533   // Check optional sequence
 534   for (int i = 4; i < last; i += 5) {
 535     if (cb[i] != Bytecodes::_aload_0) return false;
 536     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 537     if (cb[i+2] != Bytecodes::_putfield) return false;
 538   }
 539   return true;
 540 }
 541 
 542 
 543 bool Method::compute_has_loops_flag() {
 544   BytecodeStream bcs(this);
 545   Bytecodes::Code bc;
 546 
 547   while ((bc = bcs.next()) >= 0) {
 548     switch( bc ) {
 549       case Bytecodes::_ifeq:
 550       case Bytecodes::_ifnull:
 551       case Bytecodes::_iflt:
 552       case Bytecodes::_ifle:
 553       case Bytecodes::_ifne:
 554       case Bytecodes::_ifnonnull:
 555       case Bytecodes::_ifgt:
 556       case Bytecodes::_ifge:
 557       case Bytecodes::_if_icmpeq:
 558       case Bytecodes::_if_icmpne:
 559       case Bytecodes::_if_icmplt:
 560       case Bytecodes::_if_icmpgt:
 561       case Bytecodes::_if_icmple:
 562       case Bytecodes::_if_icmpge:
 563       case Bytecodes::_if_acmpeq:
 564       case Bytecodes::_if_acmpne:
 565       case Bytecodes::_goto:
 566       case Bytecodes::_jsr:
 567         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 568         break;
 569 
 570       case Bytecodes::_goto_w:
 571       case Bytecodes::_jsr_w:
 572         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 573         break;
 574 
 575       default:
 576         break;
 577     }
 578   }
 579   _access_flags.set_loops_flag_init();
 580   return _access_flags.has_loops();
 581 }
 582 
 583 bool Method::is_final_method(AccessFlags class_access_flags) const {
 584   // or "does_not_require_vtable_entry"
 585   // default method or overpass can occur, is not final (reuses vtable entry)
 586   // private methods in classes get vtable entries for backward class compatibility.
 587   if (is_overpass() || is_default_method())  return false;
 588   return is_final() || class_access_flags.is_final();
 589 }
 590 
 591 bool Method::is_final_method() const {
 592   return is_final_method(method_holder()->access_flags());
 593 }
 594 
 595 bool Method::is_default_method() const {
 596   if (method_holder() != NULL &&
 597       method_holder()->is_interface() &&
 598       !is_abstract() && !is_private()) {
 599     return true;
 600   } else {
 601     return false;
 602   }
 603 }
 604 
 605 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 606   if (is_final_method(class_access_flags))  return true;
 607 #ifdef ASSERT
 608   ResourceMark rm;
 609   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 610   if (class_access_flags.is_interface()) {
 611       assert(is_nonv == is_static() || is_nonv == is_private(),
 612              "nonvirtual unexpected for non-static, non-private: %s",
 613              name_and_sig_as_C_string());
 614   }
 615 #endif
 616   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 617   return vtable_index() == nonvirtual_vtable_index;
 618 }
 619 
 620 bool Method::can_be_statically_bound() const {
 621   return can_be_statically_bound(method_holder()->access_flags());
 622 }
 623 
 624 bool Method::is_accessor() const {
 625   return is_getter() || is_setter();
 626 }
 627 
 628 bool Method::is_getter() const {
 629   if (code_size() != 5) return false;
 630   if (size_of_parameters() != 1) return false;
 631   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 632   if (java_code_at(1) != Bytecodes::_getfield) return false;
 633   switch (java_code_at(4)) {
 634     case Bytecodes::_ireturn:
 635     case Bytecodes::_lreturn:
 636     case Bytecodes::_freturn:
 637     case Bytecodes::_dreturn:
 638     case Bytecodes::_areturn:
 639       break;
 640     default:
 641       return false;
 642   }
 643   return true;
 644 }
 645 
 646 bool Method::is_setter() const {
 647   if (code_size() != 6) return false;
 648   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 649   switch (java_code_at(1)) {
 650     case Bytecodes::_iload_1:
 651     case Bytecodes::_aload_1:
 652     case Bytecodes::_fload_1:
 653       if (size_of_parameters() != 2) return false;
 654       break;
 655     case Bytecodes::_dload_1:
 656     case Bytecodes::_lload_1:
 657       if (size_of_parameters() != 3) return false;
 658       break;
 659     default:
 660       return false;
 661   }
 662   if (java_code_at(2) != Bytecodes::_putfield) return false;
 663   if (java_code_at(5) != Bytecodes::_return)   return false;
 664   return true;
 665 }
 666 
 667 bool Method::is_constant_getter() const {
 668   int last_index = code_size() - 1;
 669   // Check if the first 1-3 bytecodes are a constant push
 670   // and the last bytecode is a return.
 671   return (2 <= code_size() && code_size() <= 4 &&
 672           Bytecodes::is_const(java_code_at(0)) &&
 673           Bytecodes::length_for(java_code_at(0)) == last_index &&
 674           Bytecodes::is_return(java_code_at(last_index)));
 675 }
 676 
 677 bool Method::is_initializer() const {
 678   return is_object_initializer() || is_static_initializer();
 679 }
 680 
 681 bool Method::has_valid_initializer_flags() const {
 682   return (is_static() ||
 683           method_holder()->major_version() < 51);
 684 }
 685 
 686 bool Method::is_static_initializer() const {
 687   // For classfiles version 51 or greater, ensure that the clinit method is
 688   // static.  Non-static methods with the name "<clinit>" are not static
 689   // initializers. (older classfiles exempted for backward compatibility)
 690   return name() == vmSymbols::class_initializer_name() &&
 691          has_valid_initializer_flags();
 692 }
 693 
 694 bool Method::is_object_initializer() const {
 695    return name() == vmSymbols::object_initializer_name();
 696 }
 697 
 698 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 699   int length = method->checked_exceptions_length();
 700   if (length == 0) {  // common case
 701     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 702   } else {
 703     methodHandle h_this(THREAD, method);
 704     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 705     objArrayHandle mirrors (THREAD, m_oop);
 706     for (int i = 0; i < length; i++) {
 707       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 708       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 709       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 710       mirrors->obj_at_put(i, k->java_mirror());
 711     }
 712     return mirrors;
 713   }
 714 };
 715 
 716 
 717 int Method::line_number_from_bci(int bci) const {
 718   int best_bci  =  0;
 719   int best_line = -1;
 720   if (bci == SynchronizationEntryBCI) bci = 0;
 721   if (0 <= bci && bci < code_size() && has_linenumber_table()) {
 722     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 723     // Not necessarily sorted and not necessarily one-to-one.
 724     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 725     while (stream.read_pair()) {
 726       if (stream.bci() == bci) {
 727         // perfect match
 728         return stream.line();
 729       } else {
 730         // update best_bci/line
 731         if (stream.bci() < bci && stream.bci() >= best_bci) {
 732           best_bci  = stream.bci();
 733           best_line = stream.line();
 734         }
 735       }
 736     }
 737   }
 738   return best_line;
 739 }
 740 
 741 
 742 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 743   if( constants()->tag_at(klass_index).is_unresolved_klass()) {
 744     Thread *thread = Thread::current();
 745     Symbol* klass_name = constants()->klass_name_at(klass_index);
 746     Handle loader(thread, method_holder()->class_loader());
 747     Handle prot  (thread, method_holder()->protection_domain());
 748     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 749   } else {
 750     return true;
 751   }
 752 }
 753 
 754 
 755 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 756   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 757   if (must_be_resolved) {
 758     // Make sure klass is resolved in constantpool.
 759     if (constants()->tag_at(klass_index).is_unresolved_klass()) {
 760       return false;
 761     }
 762   }
 763   return is_klass_loaded_by_klass_index(klass_index);
 764 }
 765 
 766 
 767 void Method::set_native_function(address function, bool post_event_flag) {
 768   assert(function != NULL, "use clear_native_function to unregister natives");
 769   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 770   address* native_function = native_function_addr();
 771 
 772   // We can see racers trying to place the same native function into place. Once
 773   // is plenty.
 774   address current = *native_function;
 775   if (current == function) return;
 776   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 777       function != NULL) {
 778     // native_method_throw_unsatisfied_link_error_entry() should only
 779     // be passed when post_event_flag is false.
 780     assert(function !=
 781       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 782       "post_event_flag mis-match");
 783 
 784     // post the bind event, and possible change the bind function
 785     JvmtiExport::post_native_method_bind(this, &function);
 786   }
 787   *native_function = function;
 788   // This function can be called more than once. We must make sure that we always
 789   // use the latest registered method -> check if a stub already has been generated.
 790   // If so, we have to make it not_entrant.
 791   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 792   if (nm != NULL) {
 793     nm->make_not_entrant();
 794   }
 795 }
 796 
 797 
 798 bool Method::has_native_function() const {
 799   if (is_method_handle_intrinsic())
 800     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 801   address func = native_function();
 802   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 803 }
 804 
 805 
 806 void Method::clear_native_function() {
 807   // Note: is_method_handle_intrinsic() is allowed here.
 808   set_native_function(
 809     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 810     !native_bind_event_is_interesting);
 811   clear_code();
 812 }
 813 
 814 address Method::critical_native_function() {
 815   methodHandle mh(this);
 816   return NativeLookup::lookup_critical_entry(mh);
 817 }
 818 
 819 
 820 void Method::set_signature_handler(address handler) {
 821   address* signature_handler =  signature_handler_addr();
 822   *signature_handler = handler;
 823 }
 824 
 825 
 826 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 827   if (PrintCompilation && report) {
 828     ttyLocker ttyl;
 829     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 830     if (comp_level == CompLevel_all) {
 831       tty->print("all levels ");
 832     } else {
 833       tty->print("levels ");
 834       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 835         tty->print("%d ", i);
 836       }
 837     }
 838     this->print_short_name(tty);
 839     int size = this->code_size();
 840     if (size > 0) {
 841       tty->print(" (%d bytes)", size);
 842     }
 843     if (reason != NULL) {
 844       tty->print("   %s", reason);
 845     }
 846     tty->cr();
 847   }
 848   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 849     ttyLocker ttyl;
 850     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 851                      os::current_thread_id(), is_osr, comp_level);
 852     if (reason != NULL) {
 853       xtty->print(" reason=\'%s\'", reason);
 854     }
 855     xtty->method(this);
 856     xtty->stamp();
 857     xtty->end_elem();
 858   }
 859 }
 860 
 861 bool Method::is_always_compilable() const {
 862   // Generated adapters must be compiled
 863   if (is_method_handle_intrinsic() && is_synthetic()) {
 864     assert(!is_not_c1_compilable(), "sanity check");
 865     assert(!is_not_c2_compilable(), "sanity check");
 866     return true;
 867   }
 868 
 869   return false;
 870 }
 871 
 872 bool Method::is_not_compilable(int comp_level) const {
 873   if (number_of_breakpoints() > 0)
 874     return true;
 875   if (is_always_compilable())
 876     return false;
 877   if (comp_level == CompLevel_any)
 878     return is_not_c1_compilable() || is_not_c2_compilable();
 879   if (is_c1_compile(comp_level))
 880     return is_not_c1_compilable();
 881   if (is_c2_compile(comp_level))
 882     return is_not_c2_compilable();
 883   return false;
 884 }
 885 
 886 // call this when compiler finds that this method is not compilable
 887 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 888   if (is_always_compilable()) {
 889     // Don't mark a method which should be always compilable
 890     return;
 891   }
 892   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 893   if (comp_level == CompLevel_all) {
 894     set_not_c1_compilable();
 895     set_not_c2_compilable();
 896   } else {
 897     if (is_c1_compile(comp_level))
 898       set_not_c1_compilable();
 899     if (is_c2_compile(comp_level))
 900       set_not_c2_compilable();
 901   }
 902   CompilationPolicy::policy()->disable_compilation(this);
 903   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 904 }
 905 
 906 bool Method::is_not_osr_compilable(int comp_level) const {
 907   if (is_not_compilable(comp_level))
 908     return true;
 909   if (comp_level == CompLevel_any)
 910     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 911   if (is_c1_compile(comp_level))
 912     return is_not_c1_osr_compilable();
 913   if (is_c2_compile(comp_level))
 914     return is_not_c2_osr_compilable();
 915   return false;
 916 }
 917 
 918 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 919   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 920   if (comp_level == CompLevel_all) {
 921     set_not_c1_osr_compilable();
 922     set_not_c2_osr_compilable();
 923   } else {
 924     if (is_c1_compile(comp_level))
 925       set_not_c1_osr_compilable();
 926     if (is_c2_compile(comp_level))
 927       set_not_c2_osr_compilable();
 928   }
 929   CompilationPolicy::policy()->disable_compilation(this);
 930   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 931 }
 932 
 933 // Revert to using the interpreter and clear out the nmethod
 934 void Method::clear_code(bool acquire_lock /* = true */) {
 935   MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
 936   // this may be NULL if c2i adapters have not been made yet
 937   // Only should happen at allocate time.
 938   if (adapter() == NULL) {
 939     _from_compiled_entry    = NULL;
 940     _from_compiled_value_entry = NULL;
 941   } else {
 942     _from_compiled_entry    = adapter()->get_c2i_entry();
 943     _from_compiled_value_entry = adapter()->get_c2i_entry();
 944   }
 945   OrderAccess::storestore();
 946   _from_interpreted_entry = _i2i_entry;
 947   OrderAccess::storestore();
 948   _code = NULL;
 949 }
 950 
 951 #if INCLUDE_CDS
 952 // Called by class data sharing to remove any entry points (which are not shared)
 953 void Method::unlink_method() {
 954   _code = NULL;
 955 
 956   assert(DumpSharedSpaces, "dump time only");
 957   // Set the values to what they should be at run time. Note that
 958   // this Method can no longer be executed during dump time.
 959   _i2i_entry = Interpreter::entry_for_cds_method(this);
 960   _from_interpreted_entry = _i2i_entry;
 961 
 962   if (is_native()) {
 963     *native_function_addr() = NULL;
 964     set_signature_handler(NULL);
 965   }
 966   NOT_PRODUCT(set_compiled_invocation_count(0);)
 967 
 968   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 969   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 970   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 971   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 972   _from_compiled_value_entry = cds_adapter->get_c2i_entry_trampoline();
 973   assert(*((int*)_from_compiled_value_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 974 
 975   set_method_data(NULL);
 976   clear_method_counters();
 977 }
 978 #endif
 979 
 980 /****************************************************************************
 981 // The following illustrates how the entries work for CDS shared Methods:
 982 //
 983 // Our goal is to delay writing into a shared Method until it's compiled.
 984 // Hence, we want to determine the initial values for _i2i_entry,
 985 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
 986 //
 987 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
 988 // They also have similar signatures so that they will share the same
 989 // AdapterHandlerEntry.
 990 //
 991 // _adapter_trampoline points to a fixed location in the RW section of
 992 // the CDS archive. This location initially contains a NULL pointer. When the
 993 // first of method A or B is linked, an AdapterHandlerEntry is allocated
 994 // dynamically, and its c2i/i2c entries are generated.
 995 //
 996 // _i2i_entry and _from_interpreted_entry initially points to the same
 997 // (fixed) location in the CODE section of the CDS archive. This contains
 998 // an unconditional branch to the actual entry for "zero_locals", which is
 999 // generated at run time and may be on an arbitrary address. Thus, the
1000 // unconditional branch is also generated at run time to jump to the correct
1001 // address.
1002 //
1003 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1004 // section. This address has enough space for an unconditional branch
1005 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1006 // initialized, and the address for the actual c2i_entry is known, we emit a
1007 // branch instruction here to branch to the actual c2i_entry.
1008 //
1009 // The effect of the extra branch on the i2i and c2i entries is negligible.
1010 //
1011 // The reason for putting _adapter_trampoline in RO is many shared Methods
1012 // share the same AdapterHandlerEntry, so we can save space in the RW section
1013 // by having the extra indirection.
1014 
1015 
1016 [Method A: RW]
1017   _constMethod ----> [ConstMethod: RO]
1018                        _adapter_trampoline -----------+
1019                                                       |
1020   _i2i_entry              (same value as method B)    |
1021   _from_interpreted_entry (same value as method B)    |
1022   _from_compiled_entry    (same value as method B)    |
1023                                                       |
1024                                                       |
1025 [Method B: RW]                               +--------+
1026   _constMethod ----> [ConstMethod: RO]       |
1027                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1028                                                                                  |
1029                                                  +-------------------------------+
1030                                                  |
1031                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1032                                                               _fingerprint
1033                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1034  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1035  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1036          |                |                                                             |                 |
1037          |                |  (_cds_entry_table: CODE)                                   |                 |
1038          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1039          |                |                               (allocated at run time)       |                 |
1040          |                |  ...                           [asm code ...]               |                 |
1041          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1042          |                                                                              |                 |
1043          |                                                                              |                 |
1044          +-[compiled]-------------------------------------------------------------------+                 |
1045                                                                                                           |
1046  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1047                                     [jmp c2i_entry] ------------------------------------------------------+
1048 
1049 ***/
1050 
1051 // Called when the method_holder is getting linked. Setup entrypoints so the method
1052 // is ready to be called from interpreter, compiler, and vtables.
1053 void Method::link_method(const methodHandle& h_method, TRAPS) {
1054   // If the code cache is full, we may reenter this function for the
1055   // leftover methods that weren't linked.
1056   if (is_shared()) {
1057     address entry = Interpreter::entry_for_cds_method(h_method);
1058     assert(entry != NULL && entry == _i2i_entry,
1059            "should be correctly set during dump time");
1060     if (adapter() != NULL) {
1061       return;
1062     }
1063     assert(entry == _from_interpreted_entry,
1064            "should be correctly set during dump time");
1065   } else if (_i2i_entry != NULL) {
1066     return;
1067   }
1068   assert( _code == NULL, "nothing compiled yet" );
1069 
1070   // Setup interpreter entrypoint
1071   assert(this == h_method(), "wrong h_method()" );
1072 
1073   if (!is_shared()) {
1074     assert(adapter() == NULL, "init'd to NULL");
1075     address entry = Interpreter::entry_for_method(h_method);
1076     assert(entry != NULL, "interpreter entry must be non-null");
1077     // Sets both _i2i_entry and _from_interpreted_entry
1078     set_interpreter_entry(entry);
1079   }
1080 
1081   // Don't overwrite already registered native entries.
1082   if (is_native() && !has_native_function()) {
1083     set_native_function(
1084       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1085       !native_bind_event_is_interesting);
1086   }
1087 
1088   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1089   // special handling of vtables.  An alternative is to make adapters more
1090   // lazily by calling make_adapter() from from_compiled_entry() for the
1091   // normal calls.  For vtable calls life gets more complicated.  When a
1092   // call-site goes mega-morphic we need adapters in all methods which can be
1093   // called from the vtable.  We need adapters on such methods that get loaded
1094   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1095   // problem we'll make these lazily later.
1096   (void) make_adapters(h_method, CHECK);
1097 
1098   // ONLY USE the h_method now as make_adapter may have blocked
1099 
1100 }
1101 
1102 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1103   // Adapters for compiled code are made eagerly here.  They are fairly
1104   // small (generally < 100 bytes) and quick to make (and cached and shared)
1105   // so making them eagerly shouldn't be too expensive.
1106   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh, CHECK_0);
1107   if (adapter == NULL ) {
1108     if (!is_init_completed()) {
1109       // Don't throw exceptions during VM initialization because java.lang.* classes
1110       // might not have been initialized, causing problems when constructing the
1111       // Java exception object.
1112       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1113     } else {
1114       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1115     }
1116   }
1117 
1118   if (mh->is_shared()) {
1119     assert(mh->adapter() == adapter, "must be");
1120     assert(mh->_from_compiled_entry != NULL, "must be");
1121     assert(mh->_from_compiled_value_entry != NULL, "must be");
1122   } else {
1123     mh->set_adapter_entry(adapter);
1124     mh->_from_compiled_entry = adapter->get_c2i_entry();
1125     mh->_from_compiled_value_entry = adapter->get_c2i_entry();
1126   }
1127   return adapter->get_c2i_entry();
1128 }
1129 
1130 void Method::restore_unshareable_info(TRAPS) {
1131   assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1132 
1133   // Since restore_unshareable_info can be called more than once for a method, don't
1134   // redo any work.
1135   if (adapter() == NULL) {
1136     methodHandle mh(THREAD, this);
1137     link_method(mh, CHECK);
1138   }
1139 }
1140 
1141 address Method::from_compiled_entry_no_trampoline() const {
1142   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1143   if (code) {
1144     return code->verified_entry_point();
1145   } else {
1146     return adapter()->get_c2i_entry();
1147   }
1148 }
1149 
1150 // The verified_code_entry() must be called when a invoke is resolved
1151 // on this method.
1152 
1153 // It returns the compiled code entry point, after asserting not null.
1154 // This function is called after potential safepoints so that nmethod
1155 // or adapter that it points to is still live and valid.
1156 // This function must not hit a safepoint!
1157 address Method::verified_code_entry() {
1158   debug_only(NoSafepointVerifier nsv;)
1159   assert(_from_compiled_entry != NULL, "must be set");
1160   return _from_compiled_entry;
1161 }
1162 
1163 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1164 // (could be racing a deopt).
1165 // Not inline to avoid circular ref.
1166 bool Method::check_code() const {
1167   // cached in a register or local.  There's a race on the value of the field.
1168   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1169   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1170 }
1171 
1172 // Install compiled code.  Instantly it can execute.
1173 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1174   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1175   assert( code, "use clear_code to remove code" );
1176   assert( mh->check_code(), "" );
1177 
1178   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1179 
1180   // These writes must happen in this order, because the interpreter will
1181   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1182   // which jumps to _from_compiled_entry.
1183   mh->_code = code;             // Assign before allowing compiled code to exec
1184 
1185   int comp_level = code->comp_level();
1186   // In theory there could be a race here. In practice it is unlikely
1187   // and not worth worrying about.
1188   if (comp_level > mh->highest_comp_level()) {
1189     mh->set_highest_comp_level(comp_level);
1190   }
1191 
1192   OrderAccess::storestore();
1193   mh->_from_compiled_entry = code->verified_entry_point();
1194   mh->_from_compiled_value_entry = mh->has_value_args() ? code->verified_value_entry_point() : code->verified_entry_point();
1195   OrderAccess::storestore();
1196   // Instantly compiled code can execute.
1197   if (!mh->is_method_handle_intrinsic())
1198     mh->_from_interpreted_entry = mh->get_i2c_entry();
1199 }
1200 
1201 
1202 bool Method::is_overridden_in(Klass* k) const {
1203   InstanceKlass* ik = InstanceKlass::cast(k);
1204 
1205   if (ik->is_interface()) return false;
1206 
1207   // If method is an interface, we skip it - except if it
1208   // is a miranda method
1209   if (method_holder()->is_interface()) {
1210     // Check that method is not a miranda method
1211     if (ik->lookup_method(name(), signature()) == NULL) {
1212       // No implementation exist - so miranda method
1213       return false;
1214     }
1215     return true;
1216   }
1217 
1218   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1219   if (!has_vtable_index()) {
1220     return false;
1221   } else {
1222     Method* vt_m = ik->method_at_vtable(vtable_index());
1223     return vt_m != this;
1224   }
1225 }
1226 
1227 
1228 // give advice about whether this Method* should be cached or not
1229 bool Method::should_not_be_cached() const {
1230   if (is_old()) {
1231     // This method has been redefined. It is either EMCP or obsolete
1232     // and we don't want to cache it because that would pin the method
1233     // down and prevent it from being collectible if and when it
1234     // finishes executing.
1235     return true;
1236   }
1237 
1238   // caching this method should be just fine
1239   return false;
1240 }
1241 
1242 
1243 /**
1244  *  Returns true if this is one of the specially treated methods for
1245  *  security related stack walks (like Reflection.getCallerClass).
1246  */
1247 bool Method::is_ignored_by_security_stack_walk() const {
1248   if (intrinsic_id() == vmIntrinsics::_invoke) {
1249     // This is Method.invoke() -- ignore it
1250     return true;
1251   }
1252   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1253     // This is an auxilary frame -- ignore it
1254     return true;
1255   }
1256   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1257     // This is an internal adapter frame for method handles -- ignore it
1258     return true;
1259   }
1260   return false;
1261 }
1262 
1263 
1264 // Constant pool structure for invoke methods:
1265 enum {
1266   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1267   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1268   _imcp_limit
1269 };
1270 
1271 // Test if this method is an MH adapter frame generated by Java code.
1272 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1273 bool Method::is_compiled_lambda_form() const {
1274   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1275 }
1276 
1277 // Test if this method is an internal MH primitive method.
1278 bool Method::is_method_handle_intrinsic() const {
1279   vmIntrinsics::ID iid = intrinsic_id();
1280   return (MethodHandles::is_signature_polymorphic(iid) &&
1281           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1282 }
1283 
1284 bool Method::has_member_arg() const {
1285   vmIntrinsics::ID iid = intrinsic_id();
1286   return (MethodHandles::is_signature_polymorphic(iid) &&
1287           MethodHandles::has_member_arg(iid));
1288 }
1289 
1290 // Make an instance of a signature-polymorphic internal MH primitive.
1291 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1292                                                          Symbol* signature,
1293                                                          TRAPS) {
1294   ResourceMark rm;
1295   methodHandle empty;
1296 
1297   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1298   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1299   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1300   if (TraceMethodHandles) {
1301     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1302   }
1303 
1304   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1305   name->increment_refcount();
1306   signature->increment_refcount();
1307 
1308   int cp_length = _imcp_limit;
1309   ClassLoaderData* loader_data = holder->class_loader_data();
1310   constantPoolHandle cp;
1311   {
1312     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1313     cp = constantPoolHandle(THREAD, cp_oop);
1314   }
1315   cp->set_pool_holder(holder);
1316   cp->symbol_at_put(_imcp_invoke_name,       name);
1317   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1318   cp->set_has_preresolution();
1319 
1320   // decide on access bits:  public or not?
1321   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1322   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1323   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1324   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1325 
1326   methodHandle m;
1327   {
1328     InlineTableSizes sizes;
1329     Method* m_oop = Method::allocate(loader_data, 0,
1330                                      accessFlags_from(flags_bits), &sizes,
1331                                      ConstMethod::NORMAL, CHECK_(empty));
1332     m = methodHandle(THREAD, m_oop);
1333   }
1334   m->set_constants(cp());
1335   m->set_name_index(_imcp_invoke_name);
1336   m->set_signature_index(_imcp_invoke_signature);
1337   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1338   assert(m->signature() == signature, "");
1339   ResultTypeFinder rtf(signature);
1340   m->constMethod()->set_result_type(rtf.type());
1341   m->compute_size_of_parameters(THREAD);
1342   m->init_intrinsic_id();
1343   assert(m->is_method_handle_intrinsic(), "");
1344 #ifdef ASSERT
1345   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1346   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1347   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1348 #endif //ASSERT
1349 
1350   // Finally, set up its entry points.
1351   assert(m->can_be_statically_bound(), "");
1352   m->set_vtable_index(Method::nonvirtual_vtable_index);
1353   m->link_method(m, CHECK_(empty));
1354 
1355   if (TraceMethodHandles && (Verbose || WizardMode)) {
1356     ttyLocker ttyl;
1357     m->print_on(tty);
1358   }
1359 
1360   return m;
1361 }
1362 
1363 Klass* Method::check_non_bcp_klass(Klass* klass) {
1364   if (klass != NULL && klass->class_loader() != NULL) {
1365     if (klass->is_objArray_klass())
1366       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1367     return klass;
1368   }
1369   return NULL;
1370 }
1371 
1372 
1373 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1374                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1375   // Code below does not work for native methods - they should never get rewritten anyway
1376   assert(!m->is_native(), "cannot rewrite native methods");
1377   // Allocate new Method*
1378   AccessFlags flags = m->access_flags();
1379 
1380   ConstMethod* cm = m->constMethod();
1381   int checked_exceptions_len = cm->checked_exceptions_length();
1382   int localvariable_len = cm->localvariable_table_length();
1383   int exception_table_len = cm->exception_table_length();
1384   int method_parameters_len = cm->method_parameters_length();
1385   int method_annotations_len = cm->method_annotations_length();
1386   int parameter_annotations_len = cm->parameter_annotations_length();
1387   int type_annotations_len = cm->type_annotations_length();
1388   int default_annotations_len = cm->default_annotations_length();
1389 
1390   InlineTableSizes sizes(
1391       localvariable_len,
1392       new_compressed_linenumber_size,
1393       exception_table_len,
1394       checked_exceptions_len,
1395       method_parameters_len,
1396       cm->generic_signature_index(),
1397       method_annotations_len,
1398       parameter_annotations_len,
1399       type_annotations_len,
1400       default_annotations_len,
1401       0);
1402 
1403   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1404   Method* newm_oop = Method::allocate(loader_data,
1405                                       new_code_length,
1406                                       flags,
1407                                       &sizes,
1408                                       m->method_type(),
1409                                       CHECK_(methodHandle()));
1410   methodHandle newm (THREAD, newm_oop);
1411 
1412   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1413   ConstMethod* newcm = newm->constMethod();
1414   int new_const_method_size = newm->constMethod()->size();
1415 
1416   // This works because the source and target are both Methods. Some compilers
1417   // (e.g., clang) complain that the target vtable pointer will be stomped,
1418   // so cast away newm()'s and m()'s Methodness.
1419   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1420 
1421   // Create shallow copy of ConstMethod.
1422   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1423 
1424   // Reset correct method/const method, method size, and parameter info
1425   newm->set_constMethod(newcm);
1426   newm->constMethod()->set_code_size(new_code_length);
1427   newm->constMethod()->set_constMethod_size(new_const_method_size);
1428   assert(newm->code_size() == new_code_length, "check");
1429   assert(newm->method_parameters_length() == method_parameters_len, "check");
1430   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1431   assert(newm->exception_table_length() == exception_table_len, "check");
1432   assert(newm->localvariable_table_length() == localvariable_len, "check");
1433   // Copy new byte codes
1434   memcpy(newm->code_base(), new_code, new_code_length);
1435   // Copy line number table
1436   if (new_compressed_linenumber_size > 0) {
1437     memcpy(newm->compressed_linenumber_table(),
1438            new_compressed_linenumber_table,
1439            new_compressed_linenumber_size);
1440   }
1441   // Copy method_parameters
1442   if (method_parameters_len > 0) {
1443     memcpy(newm->method_parameters_start(),
1444            m->method_parameters_start(),
1445            method_parameters_len * sizeof(MethodParametersElement));
1446   }
1447   // Copy checked_exceptions
1448   if (checked_exceptions_len > 0) {
1449     memcpy(newm->checked_exceptions_start(),
1450            m->checked_exceptions_start(),
1451            checked_exceptions_len * sizeof(CheckedExceptionElement));
1452   }
1453   // Copy exception table
1454   if (exception_table_len > 0) {
1455     memcpy(newm->exception_table_start(),
1456            m->exception_table_start(),
1457            exception_table_len * sizeof(ExceptionTableElement));
1458   }
1459   // Copy local variable number table
1460   if (localvariable_len > 0) {
1461     memcpy(newm->localvariable_table_start(),
1462            m->localvariable_table_start(),
1463            localvariable_len * sizeof(LocalVariableTableElement));
1464   }
1465   // Copy stackmap table
1466   if (m->has_stackmap_table()) {
1467     int code_attribute_length = m->stackmap_data()->length();
1468     Array<u1>* stackmap_data =
1469       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1470     memcpy((void*)stackmap_data->adr_at(0),
1471            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1472     newm->set_stackmap_data(stackmap_data);
1473   }
1474 
1475   // copy annotations over to new method
1476   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1477   return newm;
1478 }
1479 
1480 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1481   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1482   // because we are not loading from core libraries
1483   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1484   // which does not use the class default class loader so we check for its loader here
1485   const InstanceKlass* ik = InstanceKlass::cast(holder);
1486   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1487     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1488   }
1489 
1490   // see if the klass name is well-known:
1491   Symbol* klass_name = ik->name();
1492   return vmSymbols::find_sid(klass_name);
1493 }
1494 
1495 void Method::init_intrinsic_id() {
1496   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1497   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1498   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1499   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1500 
1501   // the klass name is well-known:
1502   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1503   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1504 
1505   // ditto for method and signature:
1506   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1507   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1508       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1509       && name_id == vmSymbols::NO_SID) {
1510     return;
1511   }
1512   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1513   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1514       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1515       && sig_id == vmSymbols::NO_SID) {
1516     return;
1517   }
1518   jshort flags = access_flags().as_short();
1519 
1520   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1521   if (id != vmIntrinsics::_none) {
1522     set_intrinsic_id(id);
1523     if (id == vmIntrinsics::_Class_cast) {
1524       // Even if the intrinsic is rejected, we want to inline this simple method.
1525       set_force_inline(true);
1526     }
1527     return;
1528   }
1529 
1530   // A few slightly irregular cases:
1531   switch (klass_id) {
1532   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1533     // Second chance: check in regular Math.
1534     switch (name_id) {
1535     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1536     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1537     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1538       // pretend it is the corresponding method in the non-strict class:
1539       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1540       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1541       break;
1542     default:
1543       break;
1544     }
1545     break;
1546 
1547   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1548   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1549   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1550     if (!is_native())  break;
1551     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1552     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1553       id = vmIntrinsics::_none;
1554     break;
1555 
1556   default:
1557     break;
1558   }
1559 
1560   if (id != vmIntrinsics::_none) {
1561     // Set up its iid.  It is an alias method.
1562     set_intrinsic_id(id);
1563     return;
1564   }
1565 }
1566 
1567 // These two methods are static since a GC may move the Method
1568 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1569   if (!THREAD->can_call_java()) {
1570     // There is nothing useful this routine can do from within the Compile thread.
1571     // Hopefully, the signature contains only well-known classes.
1572     // We could scan for this and return true/false, but the caller won't care.
1573     return false;
1574   }
1575   bool sig_is_loaded = true;
1576   Handle class_loader(THREAD, m->method_holder()->class_loader());
1577   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1578   ResourceMark rm(THREAD);
1579   Symbol*  signature = m->signature();
1580   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1581     if (ss.is_object()) {
1582       Symbol* sym = ss.as_symbol(CHECK_(false));
1583       Symbol*  name  = sym;
1584       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1585                                              protection_domain, THREAD);
1586       // We are loading classes eagerly. If a ClassNotFoundException or
1587       // a LinkageError was generated, be sure to ignore it.
1588       if (HAS_PENDING_EXCEPTION) {
1589         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1590             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1591           CLEAR_PENDING_EXCEPTION;
1592         } else {
1593           return false;
1594         }
1595       }
1596       if( klass == NULL) { sig_is_loaded = false; }
1597     }
1598   }
1599   return sig_is_loaded;
1600 }
1601 
1602 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1603   Handle class_loader(THREAD, m->method_holder()->class_loader());
1604   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1605   ResourceMark rm(THREAD);
1606   Symbol*  signature = m->signature();
1607   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1608     if (ss.type() == T_OBJECT) {
1609       Symbol* name = ss.as_symbol_or_null();
1610       if (name == NULL) return true;
1611       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1612       if (klass == NULL) return true;
1613     }
1614   }
1615   return false;
1616 }
1617 
1618 // Exposed so field engineers can debug VM
1619 void Method::print_short_name(outputStream* st) {
1620   ResourceMark rm;
1621 #ifdef PRODUCT
1622   st->print(" %s::", method_holder()->external_name());
1623 #else
1624   st->print(" %s::", method_holder()->internal_name());
1625 #endif
1626   name()->print_symbol_on(st);
1627   if (WizardMode) signature()->print_symbol_on(st);
1628   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1629     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1630 }
1631 
1632 // Comparer for sorting an object array containing
1633 // Method*s.
1634 static int method_comparator(Method* a, Method* b) {
1635   return a->name()->fast_compare(b->name());
1636 }
1637 
1638 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1639 // default_methods also uses this without the ordering for fast find_method
1640 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1641   int length = methods->length();
1642   if (length > 1) {
1643     {
1644       NoSafepointVerifier nsv;
1645       QuickSort::sort(methods->data(), length, method_comparator, idempotent);
1646     }
1647     // Reset method ordering
1648     if (set_idnums) {
1649       for (int i = 0; i < length; i++) {
1650         Method* m = methods->at(i);
1651         m->set_method_idnum(i);
1652         m->set_orig_method_idnum(i);
1653       }
1654     }
1655   }
1656 }
1657 
1658 //-----------------------------------------------------------------------------------
1659 // Non-product code unless JVM/TI needs it
1660 
1661 #if !defined(PRODUCT) || INCLUDE_JVMTI
1662 class SignatureTypePrinter : public SignatureTypeNames {
1663  private:
1664   outputStream* _st;
1665   bool _use_separator;
1666 
1667   void type_name(const char* name) {
1668     if (_use_separator) _st->print(", ");
1669     _st->print("%s", name);
1670     _use_separator = true;
1671   }
1672 
1673  public:
1674   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1675     _st = st;
1676     _use_separator = false;
1677   }
1678 
1679   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1680   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1681 };
1682 
1683 
1684 void Method::print_name(outputStream* st) {
1685   Thread *thread = Thread::current();
1686   ResourceMark rm(thread);
1687   st->print("%s ", is_static() ? "static" : "virtual");
1688   if (WizardMode) {
1689     st->print("%s.", method_holder()->internal_name());
1690     name()->print_symbol_on(st);
1691     signature()->print_symbol_on(st);
1692   } else {
1693     SignatureTypePrinter sig(signature(), st);
1694     sig.print_returntype();
1695     st->print(" %s.", method_holder()->internal_name());
1696     name()->print_symbol_on(st);
1697     st->print("(");
1698     sig.print_parameters();
1699     st->print(")");
1700   }
1701 }
1702 #endif // !PRODUCT || INCLUDE_JVMTI
1703 
1704 
1705 void Method::print_codes_on(outputStream* st) const {
1706   print_codes_on(0, code_size(), st);
1707 }
1708 
1709 void Method::print_codes_on(int from, int to, outputStream* st) const {
1710   Thread *thread = Thread::current();
1711   ResourceMark rm(thread);
1712   methodHandle mh (thread, (Method*)this);
1713   BytecodeStream s(mh);
1714   s.set_interval(from, to);
1715   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1716   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1717 }
1718 
1719 
1720 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1721 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1722 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1723 // as end-of-stream terminator.
1724 
1725 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1726   // bci and line number does not compress into single byte.
1727   // Write out escape character and use regular compression for bci and line number.
1728   write_byte((jubyte)0xFF);
1729   write_signed_int(bci_delta);
1730   write_signed_int(line_delta);
1731 }
1732 
1733 // See comment in method.hpp which explains why this exists.
1734 #if defined(_M_AMD64) && _MSC_VER >= 1400
1735 #pragma optimize("", off)
1736 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1737   write_pair_inline(bci, line);
1738 }
1739 #pragma optimize("", on)
1740 #endif
1741 
1742 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1743   _bci = 0;
1744   _line = 0;
1745 };
1746 
1747 
1748 bool CompressedLineNumberReadStream::read_pair() {
1749   jubyte next = read_byte();
1750   // Check for terminator
1751   if (next == 0) return false;
1752   if (next == 0xFF) {
1753     // Escape character, regular compression used
1754     _bci  += read_signed_int();
1755     _line += read_signed_int();
1756   } else {
1757     // Single byte compression used
1758     _bci  += next >> 3;
1759     _line += next & 0x7;
1760   }
1761   return true;
1762 }
1763 
1764 #if INCLUDE_JVMTI
1765 
1766 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1767   BreakpointInfo* bp = method_holder()->breakpoints();
1768   for (; bp != NULL; bp = bp->next()) {
1769     if (bp->match(this, bci)) {
1770       return bp->orig_bytecode();
1771     }
1772   }
1773   {
1774     ResourceMark rm;
1775     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1776   }
1777   return Bytecodes::_shouldnotreachhere;
1778 }
1779 
1780 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1781   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1782   BreakpointInfo* bp = method_holder()->breakpoints();
1783   for (; bp != NULL; bp = bp->next()) {
1784     if (bp->match(this, bci)) {
1785       bp->set_orig_bytecode(code);
1786       // and continue, in case there is more than one
1787     }
1788   }
1789 }
1790 
1791 void Method::set_breakpoint(int bci) {
1792   InstanceKlass* ik = method_holder();
1793   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1794   bp->set_next(ik->breakpoints());
1795   ik->set_breakpoints(bp);
1796   // do this last:
1797   bp->set(this);
1798 }
1799 
1800 static void clear_matches(Method* m, int bci) {
1801   InstanceKlass* ik = m->method_holder();
1802   BreakpointInfo* prev_bp = NULL;
1803   BreakpointInfo* next_bp;
1804   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1805     next_bp = bp->next();
1806     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1807     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1808       // do this first:
1809       bp->clear(m);
1810       // unhook it
1811       if (prev_bp != NULL)
1812         prev_bp->set_next(next_bp);
1813       else
1814         ik->set_breakpoints(next_bp);
1815       delete bp;
1816       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1817       // at same location. So we have multiple matching (method_index and bci)
1818       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1819       // breakpoint for clear_breakpoint request and keep all other method versions
1820       // BreakpointInfo for future clear_breakpoint request.
1821       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1822       // which is being called when class is unloaded. We delete all the Breakpoint
1823       // information for all versions of method. We may not correctly restore the original
1824       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1825       // so these methods won't be used anymore.
1826       if (bci >= 0) {
1827         break;
1828       }
1829     } else {
1830       // This one is a keeper.
1831       prev_bp = bp;
1832     }
1833   }
1834 }
1835 
1836 void Method::clear_breakpoint(int bci) {
1837   assert(bci >= 0, "");
1838   clear_matches(this, bci);
1839 }
1840 
1841 void Method::clear_all_breakpoints() {
1842   clear_matches(this, -1);
1843 }
1844 
1845 #endif // INCLUDE_JVMTI
1846 
1847 int Method::invocation_count() {
1848   MethodCounters *mcs = method_counters();
1849   if (TieredCompilation) {
1850     MethodData* const mdo = method_data();
1851     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1852         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1853       return InvocationCounter::count_limit;
1854     } else {
1855       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1856              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1857     }
1858   } else {
1859     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1860   }
1861 }
1862 
1863 int Method::backedge_count() {
1864   MethodCounters *mcs = method_counters();
1865   if (TieredCompilation) {
1866     MethodData* const mdo = method_data();
1867     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1868         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1869       return InvocationCounter::count_limit;
1870     } else {
1871       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1872              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1873     }
1874   } else {
1875     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1876   }
1877 }
1878 
1879 int Method::highest_comp_level() const {
1880   const MethodCounters* mcs = method_counters();
1881   if (mcs != NULL) {
1882     return mcs->highest_comp_level();
1883   } else {
1884     return CompLevel_none;
1885   }
1886 }
1887 
1888 int Method::highest_osr_comp_level() const {
1889   const MethodCounters* mcs = method_counters();
1890   if (mcs != NULL) {
1891     return mcs->highest_osr_comp_level();
1892   } else {
1893     return CompLevel_none;
1894   }
1895 }
1896 
1897 void Method::set_highest_comp_level(int level) {
1898   MethodCounters* mcs = method_counters();
1899   if (mcs != NULL) {
1900     mcs->set_highest_comp_level(level);
1901   }
1902 }
1903 
1904 void Method::set_highest_osr_comp_level(int level) {
1905   MethodCounters* mcs = method_counters();
1906   if (mcs != NULL) {
1907     mcs->set_highest_osr_comp_level(level);
1908   }
1909 }
1910 
1911 #if INCLUDE_JVMTI
1912 
1913 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1914   _bci = bci;
1915   _name_index = m->name_index();
1916   _signature_index = m->signature_index();
1917   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1918   if (_orig_bytecode == Bytecodes::_breakpoint)
1919     _orig_bytecode = m->orig_bytecode_at(_bci);
1920   _next = NULL;
1921 }
1922 
1923 void BreakpointInfo::set(Method* method) {
1924 #ifdef ASSERT
1925   {
1926     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1927     if (code == Bytecodes::_breakpoint)
1928       code = method->orig_bytecode_at(_bci);
1929     assert(orig_bytecode() == code, "original bytecode must be the same");
1930   }
1931 #endif
1932   Thread *thread = Thread::current();
1933   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1934   method->incr_number_of_breakpoints(thread);
1935   SystemDictionary::notice_modification();
1936   {
1937     // Deoptimize all dependents on this method
1938     HandleMark hm(thread);
1939     methodHandle mh(thread, method);
1940     CodeCache::flush_dependents_on_method(mh);
1941   }
1942 }
1943 
1944 void BreakpointInfo::clear(Method* method) {
1945   *method->bcp_from(_bci) = orig_bytecode();
1946   assert(method->number_of_breakpoints() > 0, "must not go negative");
1947   method->decr_number_of_breakpoints(Thread::current());
1948 }
1949 
1950 #endif // INCLUDE_JVMTI
1951 
1952 // jmethodID handling
1953 
1954 // This is a block allocating object, sort of like JNIHandleBlock, only a
1955 // lot simpler.
1956 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1957 // never get rid of it.
1958 
1959 static const int min_block_size = 8;
1960 
1961 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1962   friend class JNIMethodBlock;
1963   Method**        _methods;
1964   int             _number_of_methods;
1965   int             _top;
1966   JNIMethodBlockNode* _next;
1967 
1968  public:
1969 
1970   JNIMethodBlockNode(int num_methods = min_block_size);
1971 
1972   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1973 
1974   void ensure_methods(int num_addl_methods) {
1975     if (_top < _number_of_methods) {
1976       num_addl_methods -= _number_of_methods - _top;
1977       if (num_addl_methods <= 0) {
1978         return;
1979       }
1980     }
1981     if (_next == NULL) {
1982       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1983     } else {
1984       _next->ensure_methods(num_addl_methods);
1985     }
1986   }
1987 };
1988 
1989 class JNIMethodBlock : public CHeapObj<mtClass> {
1990   JNIMethodBlockNode _head;
1991   JNIMethodBlockNode *_last_free;
1992  public:
1993   static Method* const _free_method;
1994 
1995   JNIMethodBlock(int initial_capacity = min_block_size)
1996       : _head(initial_capacity), _last_free(&_head) {}
1997 
1998   void ensure_methods(int num_addl_methods) {
1999     _last_free->ensure_methods(num_addl_methods);
2000   }
2001 
2002   Method** add_method(Method* m) {
2003     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2004       if (b->_top < b->_number_of_methods) {
2005         // top points to the next free entry.
2006         int i = b->_top;
2007         b->_methods[i] = m;
2008         b->_top++;
2009         _last_free = b;
2010         return &(b->_methods[i]);
2011       } else if (b->_top == b->_number_of_methods) {
2012         // if the next free entry ran off the block see if there's a free entry
2013         for (int i = 0; i < b->_number_of_methods; i++) {
2014           if (b->_methods[i] == _free_method) {
2015             b->_methods[i] = m;
2016             _last_free = b;
2017             return &(b->_methods[i]);
2018           }
2019         }
2020         // Only check each block once for frees.  They're very unlikely.
2021         // Increment top past the end of the block.
2022         b->_top++;
2023       }
2024       // need to allocate a next block.
2025       if (b->_next == NULL) {
2026         b->_next = _last_free = new JNIMethodBlockNode();
2027       }
2028     }
2029     guarantee(false, "Should always allocate a free block");
2030     return NULL;
2031   }
2032 
2033   bool contains(Method** m) {
2034     if (m == NULL) return false;
2035     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2036       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2037         // This is a bit of extra checking, for two reasons.  One is
2038         // that contains() deals with pointers that are passed in by
2039         // JNI code, so making sure that the pointer is aligned
2040         // correctly is valuable.  The other is that <= and > are
2041         // technically not defined on pointers, so the if guard can
2042         // pass spuriously; no modern compiler is likely to make that
2043         // a problem, though (and if one did, the guard could also
2044         // fail spuriously, which would be bad).
2045         ptrdiff_t idx = m - b->_methods;
2046         if (b->_methods + idx == m) {
2047           return true;
2048         }
2049       }
2050     }
2051     return false;  // not found
2052   }
2053 
2054   // Doesn't really destroy it, just marks it as free so it can be reused.
2055   void destroy_method(Method** m) {
2056 #ifdef ASSERT
2057     assert(contains(m), "should be a methodID");
2058 #endif // ASSERT
2059     *m = _free_method;
2060   }
2061 
2062   // During class unloading the methods are cleared, which is different
2063   // than freed.
2064   void clear_all_methods() {
2065     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2066       for (int i = 0; i< b->_number_of_methods; i++) {
2067         b->_methods[i] = NULL;
2068       }
2069     }
2070   }
2071 #ifndef PRODUCT
2072   int count_methods() {
2073     // count all allocated methods
2074     int count = 0;
2075     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2076       for (int i = 0; i< b->_number_of_methods; i++) {
2077         if (b->_methods[i] != _free_method) count++;
2078       }
2079     }
2080     return count;
2081   }
2082 #endif // PRODUCT
2083 };
2084 
2085 // Something that can't be mistaken for an address or a markOop
2086 Method* const JNIMethodBlock::_free_method = (Method*)55;
2087 
2088 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2089   _number_of_methods = MAX2(num_methods, min_block_size);
2090   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2091   for (int i = 0; i < _number_of_methods; i++) {
2092     _methods[i] = JNIMethodBlock::_free_method;
2093   }
2094 }
2095 
2096 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2097   ClassLoaderData* cld = loader_data;
2098   if (!SafepointSynchronize::is_at_safepoint()) {
2099     // Have to add jmethod_ids() to class loader data thread-safely.
2100     // Also have to add the method to the list safely, which the cld lock
2101     // protects as well.
2102     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2103     if (cld->jmethod_ids() == NULL) {
2104       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2105     } else {
2106       cld->jmethod_ids()->ensure_methods(capacity);
2107     }
2108   } else {
2109     // At safepoint, we are single threaded and can set this.
2110     if (cld->jmethod_ids() == NULL) {
2111       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2112     } else {
2113       cld->jmethod_ids()->ensure_methods(capacity);
2114     }
2115   }
2116 }
2117 
2118 // Add a method id to the jmethod_ids
2119 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2120   ClassLoaderData* cld = loader_data;
2121 
2122   if (!SafepointSynchronize::is_at_safepoint()) {
2123     // Have to add jmethod_ids() to class loader data thread-safely.
2124     // Also have to add the method to the list safely, which the cld lock
2125     // protects as well.
2126     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2127     if (cld->jmethod_ids() == NULL) {
2128       cld->set_jmethod_ids(new JNIMethodBlock());
2129     }
2130     // jmethodID is a pointer to Method*
2131     return (jmethodID)cld->jmethod_ids()->add_method(m);
2132   } else {
2133     // At safepoint, we are single threaded and can set this.
2134     if (cld->jmethod_ids() == NULL) {
2135       cld->set_jmethod_ids(new JNIMethodBlock());
2136     }
2137     // jmethodID is a pointer to Method*
2138     return (jmethodID)cld->jmethod_ids()->add_method(m);
2139   }
2140 }
2141 
2142 // Mark a jmethodID as free.  This is called when there is a data race in
2143 // InstanceKlass while creating the jmethodID cache.
2144 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2145   ClassLoaderData* cld = loader_data;
2146   Method** ptr = (Method**)m;
2147   assert(cld->jmethod_ids() != NULL, "should have method handles");
2148   cld->jmethod_ids()->destroy_method(ptr);
2149 }
2150 
2151 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2152   // Can't assert the method_holder is the same because the new method has the
2153   // scratch method holder.
2154   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2155            == new_method->method_holder()->class_loader(),
2156          "changing to a different class loader");
2157   // Just change the method in place, jmethodID pointer doesn't change.
2158   *((Method**)jmid) = new_method;
2159 }
2160 
2161 bool Method::is_method_id(jmethodID mid) {
2162   Method* m = resolve_jmethod_id(mid);
2163   assert(m != NULL, "should be called with non-null method");
2164   InstanceKlass* ik = m->method_holder();
2165   ClassLoaderData* cld = ik->class_loader_data();
2166   if (cld->jmethod_ids() == NULL) return false;
2167   return (cld->jmethod_ids()->contains((Method**)mid));
2168 }
2169 
2170 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2171   if (mid == NULL) return NULL;
2172   Method* o = resolve_jmethod_id(mid);
2173   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2174     return NULL;
2175   }
2176   return o;
2177 };
2178 
2179 void Method::set_on_stack(const bool value) {
2180   // Set both the method itself and its constant pool.  The constant pool
2181   // on stack means some method referring to it is also on the stack.
2182   constants()->set_on_stack(value);
2183 
2184   bool already_set = on_stack();
2185   _access_flags.set_on_stack(value);
2186   if (value && !already_set) {
2187     MetadataOnStackMark::record(this);
2188   }
2189 }
2190 
2191 // Called when the class loader is unloaded to make all methods weak.
2192 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2193   loader_data->jmethod_ids()->clear_all_methods();
2194 }
2195 
2196 bool Method::has_method_vptr(const void* ptr) {
2197   Method m;
2198   // This assumes that the vtbl pointer is the first word of a C++ object.
2199   return dereference_vptr(&m) == dereference_vptr(ptr);
2200 }
2201 
2202 // Check that this pointer is valid by checking that the vtbl pointer matches
2203 bool Method::is_valid_method(const Method* m) {
2204   if (m == NULL) {
2205     return false;
2206   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2207     // Quick sanity check on pointer.
2208     return false;
2209   } else if (m->is_shared()) {
2210     return MetaspaceShared::is_valid_shared_method(m);
2211   } else if (Metaspace::contains_non_shared(m)) {
2212     return has_method_vptr((const void*)m);
2213   } else {
2214     return false;
2215   }
2216 }
2217 
2218 #ifndef PRODUCT
2219 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2220   out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2221 }
2222 #endif // PRODUCT
2223 
2224 
2225 // Printing
2226 
2227 #ifndef PRODUCT
2228 
2229 void Method::print_on(outputStream* st) const {
2230   ResourceMark rm;
2231   assert(is_method(), "must be method");
2232   st->print_cr("%s", internal_name());
2233   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2234   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2235   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2236   constants()->print_value_on(st); st->cr();
2237   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2238   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2239   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2240   st->print_cr(" - max stack:         %d",   max_stack());
2241   st->print_cr(" - max locals:        %d",   max_locals());
2242   st->print_cr(" - size of params:    %d",   size_of_parameters());
2243   st->print_cr(" - method size:       %d",   method_size());
2244   if (intrinsic_id() != vmIntrinsics::_none)
2245     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2246   if (highest_comp_level() != CompLevel_none)
2247     st->print_cr(" - highest level:     %d", highest_comp_level());
2248   st->print_cr(" - vtable index:      %d",   _vtable_index);
2249   if (valid_itable_index())
2250     st->print_cr(" - itable index:      %d",   itable_index());
2251   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2252   st->print(   " - adapters:          ");
2253   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2254   if (a == NULL)
2255     st->print_cr(INTPTR_FORMAT, p2i(a));
2256   else
2257     a->print_adapter_on(st);
2258   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2259   st->print_cr(" - code size:         %d",   code_size());
2260   if (code_size() != 0) {
2261     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2262     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2263   }
2264   if (method_data() != NULL) {
2265     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2266   }
2267   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2268   if (checked_exceptions_length() > 0) {
2269     CheckedExceptionElement* table = checked_exceptions_start();
2270     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2271     if (Verbose) {
2272       for (int i = 0; i < checked_exceptions_length(); i++) {
2273         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2274       }
2275     }
2276   }
2277   if (has_linenumber_table()) {
2278     u_char* table = compressed_linenumber_table();
2279     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2280     if (Verbose) {
2281       CompressedLineNumberReadStream stream(table);
2282       while (stream.read_pair()) {
2283         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2284       }
2285     }
2286   }
2287   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2288   if (localvariable_table_length() > 0) {
2289     LocalVariableTableElement* table = localvariable_table_start();
2290     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2291     if (Verbose) {
2292       for (int i = 0; i < localvariable_table_length(); i++) {
2293         int bci = table[i].start_bci;
2294         int len = table[i].length;
2295         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2296         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2297         int slot = table[i].slot;
2298         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2299       }
2300     }
2301   }
2302   if (code() != NULL) {
2303     st->print   (" - compiled code: ");
2304     code()->print_value_on(st);
2305   }
2306   if (is_native()) {
2307     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2308     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2309   }
2310 }
2311 
2312 void Method::print_linkage_flags(outputStream* st) {
2313   access_flags().print_on(st);
2314   if (is_default_method()) {
2315     st->print("default ");
2316   }
2317   if (is_overpass()) {
2318     st->print("overpass ");
2319   }
2320 }
2321 #endif //PRODUCT
2322 
2323 void Method::print_value_on(outputStream* st) const {
2324   assert(is_method(), "must be method");
2325   st->print("%s", internal_name());
2326   print_address_on(st);
2327   st->print(" ");
2328   if (WizardMode) access_flags().print_on(st);
2329   name()->print_value_on(st);
2330   st->print(" ");
2331   signature()->print_value_on(st);
2332   st->print(" in ");
2333   method_holder()->print_value_on(st);
2334   if (WizardMode) st->print("#%d", _vtable_index);
2335   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2336   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2337 }
2338 
2339 #if INCLUDE_SERVICES
2340 // Size Statistics
2341 void Method::collect_statistics(KlassSizeStats *sz) const {
2342   int mysize = sz->count(this);
2343   sz->_method_bytes += mysize;
2344   sz->_method_all_bytes += mysize;
2345   sz->_rw_bytes += mysize;
2346 
2347   if (constMethod()) {
2348     constMethod()->collect_statistics(sz);
2349   }
2350   if (method_data()) {
2351     method_data()->collect_statistics(sz);
2352   }
2353 }
2354 #endif // INCLUDE_SERVICES
2355 
2356 // LogTouchedMethods and PrintTouchedMethods
2357 
2358 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2359 // the Method may be garbage collected. Let's roll our own hash table.
2360 class TouchedMethodRecord : CHeapObj<mtTracing> {
2361 public:
2362   // It's OK to store Symbols here because they will NOT be GC'ed if
2363   // LogTouchedMethods is enabled.
2364   TouchedMethodRecord* _next;
2365   Symbol* _class_name;
2366   Symbol* _method_name;
2367   Symbol* _method_signature;
2368 };
2369 
2370 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2371 static TouchedMethodRecord** _touched_method_table = NULL;
2372 
2373 void Method::log_touched(TRAPS) {
2374 
2375   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2376   Symbol* my_class = klass_name();
2377   Symbol* my_name  = name();
2378   Symbol* my_sig   = signature();
2379 
2380   unsigned int hash = my_class->identity_hash() +
2381                       my_name->identity_hash() +
2382                       my_sig->identity_hash();
2383   juint index = juint(hash) % table_size;
2384 
2385   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2386   if (_touched_method_table == NULL) {
2387     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2388                                               mtTracing, CURRENT_PC);
2389     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2390   }
2391 
2392   TouchedMethodRecord* ptr = _touched_method_table[index];
2393   while (ptr) {
2394     if (ptr->_class_name       == my_class &&
2395         ptr->_method_name      == my_name &&
2396         ptr->_method_signature == my_sig) {
2397       return;
2398     }
2399     if (ptr->_next == NULL) break;
2400     ptr = ptr->_next;
2401   }
2402   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2403   my_class->increment_refcount();
2404   my_name->increment_refcount();
2405   my_sig->increment_refcount();
2406   nptr->_class_name         = my_class;
2407   nptr->_method_name        = my_name;
2408   nptr->_method_signature   = my_sig;
2409   nptr->_next               = NULL;
2410 
2411   if (ptr == NULL) {
2412     // first
2413     _touched_method_table[index] = nptr;
2414   } else {
2415     ptr->_next = nptr;
2416   }
2417 }
2418 
2419 void Method::print_touched_methods(outputStream* out) {
2420   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2421   out->print_cr("# Method::print_touched_methods version 1");
2422   if (_touched_method_table) {
2423     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2424       TouchedMethodRecord* ptr = _touched_method_table[i];
2425       while(ptr) {
2426         ptr->_class_name->print_symbol_on(out);       out->print(".");
2427         ptr->_method_name->print_symbol_on(out);      out->print(":");
2428         ptr->_method_signature->print_symbol_on(out); out->cr();
2429         ptr = ptr->_next;
2430       }
2431     }
2432   }
2433 }
2434 
2435 // Verification
2436 
2437 void Method::verify_on(outputStream* st) {
2438   guarantee(is_method(), "object must be method");
2439   guarantee(constants()->is_constantPool(), "should be constant pool");
2440   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2441   MethodData* md = method_data();
2442   guarantee(md == NULL ||
2443       md->is_methodData(), "should be method data");
2444 }