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 "gc/shared/gcLocker.hpp"
  32 #include "gc/shared/generation.hpp"
  33 #include "interpreter/bytecodeStream.hpp"
  34 #include "interpreter/bytecodeTracer.hpp"
  35 #include "interpreter/bytecodes.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/oopMapCache.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceClosure.hpp"
  41 #include "memory/metaspaceShared.hpp"
  42 #include "memory/oopFactory.hpp"
  43 #include "memory/resourceArea.hpp"
  44 #include "memory/vtBuffer.hpp"
  45 #include "oops/constMethod.hpp"
  46 #include "oops/method.hpp"
  47 #include "oops/methodData.hpp"
  48 #include "oops/objArrayOop.inline.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "oops/symbol.hpp"
  51 #include "oops/valueKlass.hpp"
  52 #include "prims/jvmtiExport.hpp"
  53 #include "prims/methodHandles.hpp"
  54 #include "prims/nativeLookup.hpp"
  55 #include "runtime/arguments.hpp"
  56 #include "runtime/compilationPolicy.hpp"
  57 #include "runtime/frame.inline.hpp"
  58 #include "runtime/handles.inline.hpp"
  59 #include "runtime/init.hpp"
  60 #include "runtime/orderAccess.inline.hpp"
  61 #include "runtime/relocator.hpp"
  62 #include "runtime/sharedRuntime.hpp"
  63 #include "runtime/signature.hpp"
  64 #include "utilities/align.hpp"
  65 #include "utilities/quickSort.hpp"
  66 #include "utilities/vmError.hpp"
  67 #include "utilities/xmlstream.hpp"
  68 
  69 // Implementation of Method
  70 
  71 Method* Method::allocate(ClassLoaderData* loader_data,
  72                          int byte_code_size,
  73                          AccessFlags access_flags,
  74                          InlineTableSizes* sizes,
  75                          ConstMethod::MethodType method_type,
  76                          TRAPS) {
  77   assert(!access_flags.is_native() || byte_code_size == 0,
  78          "native methods should not contain byte codes");
  79   ConstMethod* cm = ConstMethod::allocate(loader_data,
  80                                           byte_code_size,
  81                                           sizes,
  82                                           method_type,
  83                                           CHECK_NULL);
  84   int size = Method::size(access_flags.is_native());
  85   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  86 }
  87 
  88 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  89   NoSafepointVerifier no_safepoint;
  90   set_constMethod(xconst);
  91   set_access_flags(access_flags);
  92   set_intrinsic_id(vmIntrinsics::_none);
  93   set_force_inline(false);
  94   set_hidden(false);
  95   set_dont_inline(false);
  96   set_has_injected_profile(false);
  97   set_method_data(NULL);
  98   clear_method_counters();
  99   set_vtable_index(Method::garbage_vtable_index);
 100 
 101   // Fix and bury in Method*
 102   set_interpreter_entry(NULL); // sets i2i entry and from_int
 103   set_adapter_entry(NULL);
 104   clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
 105 
 106   if (access_flags.is_native()) {
 107     clear_native_function();
 108     set_signature_handler(NULL);
 109   }
 110 
 111   initialize_max_vt_buffer();
 112 
 113   NOT_PRODUCT(set_compiled_invocation_count(0);)
 114 }
 115 
 116 // Release Method*.  The nmethod will be gone when we get here because
 117 // we've walked the code cache.
 118 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 119   MetadataFactory::free_metadata(loader_data, constMethod());
 120   set_constMethod(NULL);
 121   MetadataFactory::free_metadata(loader_data, method_data());
 122   set_method_data(NULL);
 123   MetadataFactory::free_metadata(loader_data, method_counters());
 124   clear_method_counters();
 125   // The nmethod will be gone when we get here.
 126   if (code() != NULL) _code = NULL;
 127 }
 128 
 129 address Method::get_i2c_entry() {
 130   assert(adapter() != NULL, "must have");
 131   return adapter()->get_i2c_entry();
 132 }
 133 
 134 address Method::get_c2i_entry() {
 135   assert(adapter() != NULL, "must have");
 136   return adapter()->get_c2i_entry();
 137 }
 138 
 139 address Method::get_c2i_unverified_entry() {
 140   assert(adapter() != NULL, "must have");
 141   return adapter()->get_c2i_unverified_entry();
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string() const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 149   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 150 }
 151 
 152 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 153   const char* klass_name = klass->external_name();
 154   int klass_name_len  = (int)strlen(klass_name);
 155   int method_name_len = method_name->utf8_length();
 156   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 157   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 158   strcpy(dest, klass_name);
 159   dest[klass_name_len] = '.';
 160   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 161   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 162   dest[len] = 0;
 163   return dest;
 164 }
 165 
 166 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 167   Symbol* klass_name = klass->name();
 168   klass_name->as_klass_external_name(buf, size);
 169   int len = (int)strlen(buf);
 170 
 171   if (len < size - 1) {
 172     buf[len++] = '.';
 173 
 174     method_name->as_C_string(&(buf[len]), size - len);
 175     len = (int)strlen(buf);
 176 
 177     signature->as_C_string(&(buf[len]), size - len);
 178   }
 179 
 180   return buf;
 181 }
 182 
 183 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 184   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 185   // access exception table
 186   ExceptionTable table(mh());
 187   int length = table.length();
 188   // iterate through all entries sequentially
 189   constantPoolHandle pool(THREAD, mh->constants());
 190   for (int i = 0; i < length; i ++) {
 191     //reacquire the table in case a GC happened
 192     ExceptionTable table(mh());
 193     int beg_bci = table.start_pc(i);
 194     int end_bci = table.end_pc(i);
 195     assert(beg_bci <= end_bci, "inconsistent exception table");
 196     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 197       // exception handler bci range covers throw_bci => investigate further
 198       int handler_bci = table.handler_pc(i);
 199       int klass_index = table.catch_type_index(i);
 200       if (klass_index == 0) {
 201         return handler_bci;
 202       } else if (ex_klass == NULL) {
 203         return handler_bci;
 204       } else {
 205         // we know the exception class => get the constraint class
 206         // this may require loading of the constraint class; if verification
 207         // fails or some other exception occurs, return handler_bci
 208         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 209         assert(k != NULL, "klass not loaded");
 210         if (ex_klass->is_subtype_of(k)) {
 211           return handler_bci;
 212         }
 213       }
 214     }
 215   }
 216 
 217   return -1;
 218 }
 219 
 220 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 221   methodHandle h_this(Thread::current(), this);
 222   // Only GC uses the OopMapCache during thread stack root scanning
 223   // any other uses generate an oopmap but do not save it in the cache.
 224   if (Universe::heap()->is_gc_active()) {
 225     method_holder()->mask_for(h_this, bci, mask);
 226   } else {
 227     OopMapCache::compute_one_oop_map(h_this, bci, mask);
 228   }
 229   return;
 230 }
 231 
 232 
 233 int Method::bci_from(address bcp) const {
 234   if (is_native() && bcp == 0) {
 235     return 0;
 236   }
 237 #ifdef ASSERT
 238   {
 239     ResourceMark rm;
 240     assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
 241            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 242            p2i(bcp), name_and_sig_as_C_string());
 243   }
 244 #endif
 245   return bcp - code_base();
 246 }
 247 
 248 
 249 int Method::validate_bci(int bci) const {
 250   return (bci == 0 || bci < code_size()) ? bci : -1;
 251 }
 252 
 253 // Return bci if it appears to be a valid bcp
 254 // Return -1 otherwise.
 255 // Used by profiling code, when invalid data is a possibility.
 256 // The caller is responsible for validating the Method* itself.
 257 int Method::validate_bci_from_bcp(address bcp) const {
 258   // keep bci as -1 if not a valid bci
 259   int bci = -1;
 260   if (bcp == 0 || bcp == code_base()) {
 261     // code_size() may return 0 and we allow 0 here
 262     // the method may be native
 263     bci = 0;
 264   } else if (contains(bcp)) {
 265     bci = bcp - code_base();
 266   }
 267   // Assert that if we have dodged any asserts, bci is negative.
 268   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 269   return bci;
 270 }
 271 
 272 address Method::bcp_from(int bci) const {
 273   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 274          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 275   address bcp = code_base() + bci;
 276   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 277   return bcp;
 278 }
 279 
 280 address Method::bcp_from(address bcp) const {
 281   if (is_native() && bcp == NULL) {
 282     return code_base();
 283   } else {
 284     return bcp;
 285   }
 286 }
 287 
 288 int Method::size(bool is_native) {
 289   // If native, then include pointers for native_function and signature_handler
 290   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 291   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 292   return align_metadata_size(header_size() + extra_words);
 293 }
 294 
 295 
 296 Symbol* Method::klass_name() const {
 297   return method_holder()->name();
 298 }
 299 
 300 
 301 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 302   log_trace(cds)("Iter(Method): %p", this);
 303 
 304   it->push(&_constMethod);
 305   it->push(&_method_data);
 306   it->push(&_method_counters);
 307 }
 308 
 309 // Attempt to return method oop to original state.  Clear any pointers
 310 // (to objects outside the shared spaces).  We won't be able to predict
 311 // where they should point in a new JVM.  Further initialize some
 312 // entries now in order allow them to be write protected later.
 313 
 314 void Method::remove_unshareable_info() {
 315   unlink_method();
 316 }
 317 
 318 void Method::set_vtable_index(int index) {
 319   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 320     // At runtime initialize_vtable is rerun as part of link_class_impl()
 321     // for a shared class loaded by the non-boot loader to obtain the loader
 322     // constraints based on the runtime classloaders' context.
 323     return; // don't write into the shared class
 324   } else {
 325     _vtable_index = index;
 326   }
 327 }
 328 
 329 void Method::set_itable_index(int index) {
 330   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 331     // At runtime initialize_itable is rerun as part of link_class_impl()
 332     // for a shared class loaded by the non-boot loader to obtain the loader
 333     // constraints based on the runtime classloaders' context. The dumptime
 334     // itable index should be the same as the runtime index.
 335     assert(_vtable_index == itable_index_max - index,
 336            "archived itable index is different from runtime index");
 337     return; // don’t write into the shared class
 338   } else {
 339     _vtable_index = itable_index_max - index;
 340   }
 341   assert(valid_itable_index(), "");
 342 }
 343 
 344 
 345 
 346 bool Method::was_executed_more_than(int n) {
 347   // Invocation counter is reset when the Method* is compiled.
 348   // If the method has compiled code we therefore assume it has
 349   // be excuted more than n times.
 350   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 351     // interpreter doesn't bump invocation counter of trivial methods
 352     // compiler does not bump invocation counter of compiled methods
 353     return true;
 354   }
 355   else if ((method_counters() != NULL &&
 356             method_counters()->invocation_counter()->carry()) ||
 357            (method_data() != NULL &&
 358             method_data()->invocation_counter()->carry())) {
 359     // The carry bit is set when the counter overflows and causes
 360     // a compilation to occur.  We don't know how many times
 361     // the counter has been reset, so we simply assume it has
 362     // been executed more than n times.
 363     return true;
 364   } else {
 365     return invocation_count() > n;
 366   }
 367 }
 368 
 369 void Method::print_invocation_count() {
 370   if (is_static()) tty->print("static ");
 371   if (is_final()) tty->print("final ");
 372   if (is_synchronized()) tty->print("synchronized ");
 373   if (is_native()) tty->print("native ");
 374   tty->print("%s::", method_holder()->external_name());
 375   name()->print_symbol_on(tty);
 376   signature()->print_symbol_on(tty);
 377 
 378   if (WizardMode) {
 379     // dump the size of the byte codes
 380     tty->print(" {%d}", code_size());
 381   }
 382   tty->cr();
 383 
 384   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 385   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 386   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 387 #ifndef PRODUCT
 388   if (CountCompiledCalls) {
 389     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 390   }
 391 #endif
 392 }
 393 
 394 // Build a MethodData* object to hold information about this method
 395 // collected in the interpreter.
 396 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 397   // Do not profile the method if metaspace has hit an OOM previously
 398   // allocating profiling data. Callers clear pending exception so don't
 399   // add one here.
 400   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 401     return;
 402   }
 403 
 404   // Grab a lock here to prevent multiple
 405   // MethodData*s from being created.
 406   MutexLocker ml(MethodData_lock, THREAD);
 407   if (method->method_data() == NULL) {
 408     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 409     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 410     if (HAS_PENDING_EXCEPTION) {
 411       CompileBroker::log_metaspace_failure();
 412       ClassLoaderDataGraph::set_metaspace_oom(true);
 413       return;   // return the exception (which is cleared)
 414     }
 415 
 416     method->set_method_data(method_data);
 417     if (PrintMethodData && (Verbose || WizardMode)) {
 418       ResourceMark rm(THREAD);
 419       tty->print("build_interpreter_method_data for ");
 420       method->print_name(tty);
 421       tty->cr();
 422       // At the end of the run, the MDO, full of data, will be dumped.
 423     }
 424   }
 425 }
 426 
 427 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 428   // Do not profile the method if metaspace has hit an OOM previously
 429   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 430     return NULL;
 431   }
 432 
 433   methodHandle mh(m);
 434   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 435   if (HAS_PENDING_EXCEPTION) {
 436     CompileBroker::log_metaspace_failure();
 437     ClassLoaderDataGraph::set_metaspace_oom(true);
 438     return NULL;   // return the exception (which is cleared)
 439   }
 440   if (!mh->init_method_counters(counters)) {
 441     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 442   }
 443 
 444   if (LogTouchedMethods) {
 445     mh->log_touched(CHECK_NULL);
 446   }
 447 
 448   return mh->method_counters();
 449 }
 450 
 451 bool Method::init_method_counters(MethodCounters* counters) {
 452   // Try to install a pointer to MethodCounters, return true on success.
 453   return Atomic::replace_if_null(counters, &_method_counters);
 454 }
 455 
 456 void Method::cleanup_inline_caches() {
 457   // The current system doesn't use inline caches in the interpreter
 458   // => nothing to do (keep this method around for future use)
 459 }
 460 
 461 
 462 int Method::extra_stack_words() {
 463   // not an inline function, to avoid a header dependency on Interpreter
 464   return extra_stack_entries() * Interpreter::stackElementSize;
 465 }
 466 
 467 
 468 void Method::compute_size_of_parameters(Thread *thread) {
 469   ArgumentSizeComputer asc(signature());
 470   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 471 }
 472 
 473 BasicType Method::result_type() const {
 474   ResultTypeFinder rtf(signature());
 475   return rtf.type();
 476 }
 477 
 478 #ifdef ASSERT
 479 // ValueKlass the method is declared to return. This must not
 480 // safepoint as it is called with references live on the stack at
 481 // locations the GC is unaware of.
 482 ValueKlass* Method::returned_value_type(Thread* thread) const {
 483   assert(is_returning_vt(), "method return type should be value type");
 484   SignatureStream ss(signature());
 485   while (!ss.at_return_type()) {
 486     ss.next();
 487   }
 488   Handle class_loader(thread, method_holder()->class_loader());
 489   Handle protection_domain(thread, method_holder()->protection_domain());
 490   Klass* k = NULL;
 491   {
 492     NoSafepointVerifier nsv;
 493     k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
 494   }
 495   assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
 496   return ValueKlass::cast(k);
 497 }
 498 #endif
 499 
 500 bool Method::is_empty_method() const {
 501   return  code_size() == 1
 502       && *code_base() == Bytecodes::_return;
 503 }
 504 
 505 
 506 bool Method::is_vanilla_constructor() const {
 507   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 508   // which only calls the superclass vanilla constructor and possibly does stores of
 509   // zero constants to local fields:
 510   //
 511   //   aload_0
 512   //   invokespecial
 513   //   indexbyte1
 514   //   indexbyte2
 515   //
 516   // followed by an (optional) sequence of:
 517   //
 518   //   aload_0
 519   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 520   //   putfield
 521   //   indexbyte1
 522   //   indexbyte2
 523   //
 524   // followed by:
 525   //
 526   //   return
 527 
 528   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 529   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 530   int size = code_size();
 531   // Check if size match
 532   if (size == 0 || size % 5 != 0) return false;
 533   address cb = code_base();
 534   int last = size - 1;
 535   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 536     // Does not call superclass default constructor
 537     return false;
 538   }
 539   // Check optional sequence
 540   for (int i = 4; i < last; i += 5) {
 541     if (cb[i] != Bytecodes::_aload_0) return false;
 542     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 543     if (cb[i+2] != Bytecodes::_putfield) return false;
 544   }
 545   return true;
 546 }
 547 
 548 
 549 bool Method::compute_has_loops_flag() {
 550   BytecodeStream bcs(this);
 551   Bytecodes::Code bc;
 552 
 553   while ((bc = bcs.next()) >= 0) {
 554     switch( bc ) {
 555       case Bytecodes::_ifeq:
 556       case Bytecodes::_ifnull:
 557       case Bytecodes::_iflt:
 558       case Bytecodes::_ifle:
 559       case Bytecodes::_ifne:
 560       case Bytecodes::_ifnonnull:
 561       case Bytecodes::_ifgt:
 562       case Bytecodes::_ifge:
 563       case Bytecodes::_if_icmpeq:
 564       case Bytecodes::_if_icmpne:
 565       case Bytecodes::_if_icmplt:
 566       case Bytecodes::_if_icmpgt:
 567       case Bytecodes::_if_icmple:
 568       case Bytecodes::_if_icmpge:
 569       case Bytecodes::_if_acmpeq:
 570       case Bytecodes::_if_acmpne:
 571       case Bytecodes::_goto:
 572       case Bytecodes::_jsr:
 573         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 574         break;
 575 
 576       case Bytecodes::_goto_w:
 577       case Bytecodes::_jsr_w:
 578         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 579         break;
 580 
 581       default:
 582         break;
 583     }
 584   }
 585   _access_flags.set_loops_flag_init();
 586   return _access_flags.has_loops();
 587 }
 588 
 589 bool Method::is_final_method(AccessFlags class_access_flags) const {
 590   // or "does_not_require_vtable_entry"
 591   // default method or overpass can occur, is not final (reuses vtable entry)
 592   // private methods in classes get vtable entries for backward class compatibility.
 593   if (is_overpass() || is_default_method())  return false;
 594   return is_final() || class_access_flags.is_final();
 595 }
 596 
 597 bool Method::is_final_method() const {
 598   return is_final_method(method_holder()->access_flags());
 599 }
 600 
 601 bool Method::is_default_method() const {
 602   if (method_holder() != NULL &&
 603       method_holder()->is_interface() &&
 604       !is_abstract() && !is_private()) {
 605     return true;
 606   } else {
 607     return false;
 608   }
 609 }
 610 
 611 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 612   if (is_final_method(class_access_flags))  return true;
 613 #ifdef ASSERT
 614   ResourceMark rm;
 615   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 616   if (class_access_flags.is_interface()) {
 617       assert(is_nonv == is_static() || is_nonv == is_private(),
 618              "nonvirtual unexpected for non-static, non-private: %s",
 619              name_and_sig_as_C_string());
 620   }
 621 #endif
 622   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 623   return vtable_index() == nonvirtual_vtable_index;
 624 }
 625 
 626 bool Method::can_be_statically_bound() const {
 627   return can_be_statically_bound(method_holder()->access_flags());
 628 }
 629 
 630 bool Method::is_accessor() const {
 631   return is_getter() || is_setter();
 632 }
 633 
 634 bool Method::is_getter() const {
 635   if (code_size() != 5) return false;
 636   if (size_of_parameters() != 1) return false;
 637   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 638   if (java_code_at(1) != Bytecodes::_getfield) return false;
 639   switch (java_code_at(4)) {
 640     case Bytecodes::_ireturn:
 641     case Bytecodes::_lreturn:
 642     case Bytecodes::_freturn:
 643     case Bytecodes::_dreturn:
 644     case Bytecodes::_areturn:
 645       break;
 646     default:
 647       return false;
 648   }
 649   return true;
 650 }
 651 
 652 bool Method::is_setter() const {
 653   if (code_size() != 6) return false;
 654   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 655   switch (java_code_at(1)) {
 656     case Bytecodes::_iload_1:
 657     case Bytecodes::_aload_1:
 658     case Bytecodes::_fload_1:
 659       if (size_of_parameters() != 2) return false;
 660       break;
 661     case Bytecodes::_dload_1:
 662     case Bytecodes::_lload_1:
 663       if (size_of_parameters() != 3) return false;
 664       break;
 665     default:
 666       return false;
 667   }
 668   if (java_code_at(2) != Bytecodes::_putfield) return false;
 669   if (java_code_at(5) != Bytecodes::_return)   return false;
 670   return true;
 671 }
 672 
 673 bool Method::is_constant_getter() const {
 674   int last_index = code_size() - 1;
 675   // Check if the first 1-3 bytecodes are a constant push
 676   // and the last bytecode is a return.
 677   return (2 <= code_size() && code_size() <= 4 &&
 678           Bytecodes::is_const(java_code_at(0)) &&
 679           Bytecodes::length_for(java_code_at(0)) == last_index &&
 680           Bytecodes::is_return(java_code_at(last_index)));
 681 }
 682 
 683 bool Method::is_initializer() const {
 684   return is_object_initializer() || is_static_initializer();
 685 }
 686 
 687 bool Method::has_valid_initializer_flags() const {
 688   return (is_static() ||
 689           method_holder()->major_version() < 51);
 690 }
 691 
 692 bool Method::is_static_initializer() const {
 693   // For classfiles version 51 or greater, ensure that the clinit method is
 694   // static.  Non-static methods with the name "<clinit>" are not static
 695   // initializers. (older classfiles exempted for backward compatibility)
 696   return name() == vmSymbols::class_initializer_name() &&
 697          has_valid_initializer_flags();
 698 }
 699 
 700 bool Method::is_object_initializer() const {
 701    return name() == vmSymbols::object_initializer_name();
 702 }
 703 
 704 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 705   int length = method->checked_exceptions_length();
 706   if (length == 0) {  // common case
 707     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 708   } else {
 709     methodHandle h_this(THREAD, method);
 710     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 711     objArrayHandle mirrors (THREAD, m_oop);
 712     for (int i = 0; i < length; i++) {
 713       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 714       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 715       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 716       mirrors->obj_at_put(i, k->java_mirror());
 717     }
 718     return mirrors;
 719   }
 720 };
 721 
 722 
 723 int Method::line_number_from_bci(int bci) const {
 724   if (bci == SynchronizationEntryBCI) bci = 0;
 725   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 726   int best_bci  =  0;
 727   int best_line = -1;
 728 
 729   if (has_linenumber_table()) {
 730     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 731     // Not necessarily sorted and not necessarily one-to-one.
 732     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 733     while (stream.read_pair()) {
 734       if (stream.bci() == bci) {
 735         // perfect match
 736         return stream.line();
 737       } else {
 738         // update best_bci/line
 739         if (stream.bci() < bci && stream.bci() >= best_bci) {
 740           best_bci  = stream.bci();
 741           best_line = stream.line();
 742         }
 743       }
 744     }
 745   }
 746   return best_line;
 747 }
 748 
 749 
 750 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 751   if( constants()->tag_at(klass_index).is_unresolved_klass() ||
 752       constants()->tag_at(klass_index).is_unresolved_value_type() ) {
 753     Thread *thread = Thread::current();
 754     Symbol* klass_name = constants()->klass_name_at(klass_index);
 755     Handle loader(thread, method_holder()->class_loader());
 756     Handle prot  (thread, method_holder()->protection_domain());
 757     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 758   } else {
 759     return true;
 760   }
 761 }
 762 
 763 
 764 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 765   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 766   if (must_be_resolved) {
 767     // Make sure klass is resolved in constantpool.
 768     if (constants()->tag_at(klass_index).is_unresolved_klass() ||
 769         constants()->tag_at(klass_index).is_unresolved_value_type()) {
 770       return false;
 771     }
 772   }
 773   return is_klass_loaded_by_klass_index(klass_index);
 774 }
 775 
 776 
 777 void Method::set_native_function(address function, bool post_event_flag) {
 778   assert(function != NULL, "use clear_native_function to unregister natives");
 779   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 780   address* native_function = native_function_addr();
 781 
 782   // We can see racers trying to place the same native function into place. Once
 783   // is plenty.
 784   address current = *native_function;
 785   if (current == function) return;
 786   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 787       function != NULL) {
 788     // native_method_throw_unsatisfied_link_error_entry() should only
 789     // be passed when post_event_flag is false.
 790     assert(function !=
 791       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 792       "post_event_flag mis-match");
 793 
 794     // post the bind event, and possible change the bind function
 795     JvmtiExport::post_native_method_bind(this, &function);
 796   }
 797   *native_function = function;
 798   // This function can be called more than once. We must make sure that we always
 799   // use the latest registered method -> check if a stub already has been generated.
 800   // If so, we have to make it not_entrant.
 801   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 802   if (nm != NULL) {
 803     nm->make_not_entrant();
 804   }
 805 }
 806 
 807 
 808 bool Method::has_native_function() const {
 809   if (is_method_handle_intrinsic())
 810     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 811   address func = native_function();
 812   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 813 }
 814 
 815 
 816 void Method::clear_native_function() {
 817   // Note: is_method_handle_intrinsic() is allowed here.
 818   set_native_function(
 819     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 820     !native_bind_event_is_interesting);
 821   clear_code();
 822 }
 823 
 824 address Method::critical_native_function() {
 825   methodHandle mh(this);
 826   return NativeLookup::lookup_critical_entry(mh);
 827 }
 828 
 829 
 830 void Method::set_signature_handler(address handler) {
 831   address* signature_handler =  signature_handler_addr();
 832   *signature_handler = handler;
 833 }
 834 
 835 
 836 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 837   if (PrintCompilation && report) {
 838     ttyLocker ttyl;
 839     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 840     if (comp_level == CompLevel_all) {
 841       tty->print("all levels ");
 842     } else {
 843       tty->print("levels ");
 844       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 845         tty->print("%d ", i);
 846       }
 847     }
 848     this->print_short_name(tty);
 849     int size = this->code_size();
 850     if (size > 0) {
 851       tty->print(" (%d bytes)", size);
 852     }
 853     if (reason != NULL) {
 854       tty->print("   %s", reason);
 855     }
 856     tty->cr();
 857   }
 858   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 859     ttyLocker ttyl;
 860     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 861                      os::current_thread_id(), is_osr, comp_level);
 862     if (reason != NULL) {
 863       xtty->print(" reason=\'%s\'", reason);
 864     }
 865     xtty->method(this);
 866     xtty->stamp();
 867     xtty->end_elem();
 868   }
 869 }
 870 
 871 bool Method::is_always_compilable() const {
 872   // Generated adapters must be compiled
 873   if (is_method_handle_intrinsic() && is_synthetic()) {
 874     assert(!is_not_c1_compilable(), "sanity check");
 875     assert(!is_not_c2_compilable(), "sanity check");
 876     return true;
 877   }
 878 
 879   return false;
 880 }
 881 
 882 bool Method::is_not_compilable(int comp_level) const {
 883   if (number_of_breakpoints() > 0)
 884     return true;
 885   if (is_always_compilable())
 886     return false;
 887   if (comp_level == CompLevel_any)
 888     return is_not_c1_compilable() || is_not_c2_compilable();
 889   if (is_c1_compile(comp_level))
 890     return is_not_c1_compilable();
 891   if (is_c2_compile(comp_level))
 892     return is_not_c2_compilable();
 893   return false;
 894 }
 895 
 896 // call this when compiler finds that this method is not compilable
 897 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 898   if (is_always_compilable()) {
 899     // Don't mark a method which should be always compilable
 900     return;
 901   }
 902   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 903   if (comp_level == CompLevel_all) {
 904     set_not_c1_compilable();
 905     set_not_c2_compilable();
 906   } else {
 907     if (is_c1_compile(comp_level))
 908       set_not_c1_compilable();
 909     if (is_c2_compile(comp_level))
 910       set_not_c2_compilable();
 911   }
 912   CompilationPolicy::policy()->disable_compilation(this);
 913   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 914 }
 915 
 916 bool Method::is_not_osr_compilable(int comp_level) const {
 917   if (is_not_compilable(comp_level))
 918     return true;
 919   if (comp_level == CompLevel_any)
 920     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 921   if (is_c1_compile(comp_level))
 922     return is_not_c1_osr_compilable();
 923   if (is_c2_compile(comp_level))
 924     return is_not_c2_osr_compilable();
 925   return false;
 926 }
 927 
 928 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 929   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 930   if (comp_level == CompLevel_all) {
 931     set_not_c1_osr_compilable();
 932     set_not_c2_osr_compilable();
 933   } else {
 934     if (is_c1_compile(comp_level))
 935       set_not_c1_osr_compilable();
 936     if (is_c2_compile(comp_level))
 937       set_not_c2_osr_compilable();
 938   }
 939   CompilationPolicy::policy()->disable_compilation(this);
 940   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 941 }
 942 
 943 // Revert to using the interpreter and clear out the nmethod
 944 void Method::clear_code(bool acquire_lock /* = true */) {
 945   MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
 946   // this may be NULL if c2i adapters have not been made yet
 947   // Only should happen at allocate time.
 948   if (adapter() == NULL) {
 949     _from_compiled_entry    = NULL;
 950   } else {
 951     _from_compiled_entry    = adapter()->get_c2i_entry();
 952   }
 953   OrderAccess::storestore();
 954   _from_interpreted_entry = _i2i_entry;
 955   OrderAccess::storestore();
 956   _code = NULL;
 957 }
 958 
 959 #if INCLUDE_CDS
 960 // Called by class data sharing to remove any entry points (which are not shared)
 961 void Method::unlink_method() {
 962   _code = NULL;
 963 
 964   assert(DumpSharedSpaces, "dump time only");
 965   // Set the values to what they should be at run time. Note that
 966   // this Method can no longer be executed during dump time.
 967   _i2i_entry = Interpreter::entry_for_cds_method(this);
 968   _from_interpreted_entry = _i2i_entry;
 969 
 970   if (is_native()) {
 971     *native_function_addr() = NULL;
 972     set_signature_handler(NULL);
 973   }
 974   NOT_PRODUCT(set_compiled_invocation_count(0);)
 975 
 976   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 977   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 978   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 979   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 980 
 981   set_method_data(NULL);
 982   clear_method_counters();
 983 }
 984 #endif
 985 
 986 /****************************************************************************
 987 // The following illustrates how the entries work for CDS shared Methods:
 988 //
 989 // Our goal is to delay writing into a shared Method until it's compiled.
 990 // Hence, we want to determine the initial values for _i2i_entry,
 991 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
 992 //
 993 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
 994 // They also have similar signatures so that they will share the same
 995 // AdapterHandlerEntry.
 996 //
 997 // _adapter_trampoline points to a fixed location in the RW section of
 998 // the CDS archive. This location initially contains a NULL pointer. When the
 999 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1000 // dynamically, and its c2i/i2c entries are generated.
1001 //
1002 // _i2i_entry and _from_interpreted_entry initially points to the same
1003 // (fixed) location in the CODE section of the CDS archive. This contains
1004 // an unconditional branch to the actual entry for "zero_locals", which is
1005 // generated at run time and may be on an arbitrary address. Thus, the
1006 // unconditional branch is also generated at run time to jump to the correct
1007 // address.
1008 //
1009 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1010 // section. This address has enough space for an unconditional branch
1011 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1012 // initialized, and the address for the actual c2i_entry is known, we emit a
1013 // branch instruction here to branch to the actual c2i_entry.
1014 //
1015 // The effect of the extra branch on the i2i and c2i entries is negligible.
1016 //
1017 // The reason for putting _adapter_trampoline in RO is many shared Methods
1018 // share the same AdapterHandlerEntry, so we can save space in the RW section
1019 // by having the extra indirection.
1020 
1021 
1022 [Method A: RW]
1023   _constMethod ----> [ConstMethod: RO]
1024                        _adapter_trampoline -----------+
1025                                                       |
1026   _i2i_entry              (same value as method B)    |
1027   _from_interpreted_entry (same value as method B)    |
1028   _from_compiled_entry    (same value as method B)    |
1029                                                       |
1030                                                       |
1031 [Method B: RW]                               +--------+
1032   _constMethod ----> [ConstMethod: RO]       |
1033                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1034                                                                                  |
1035                                                  +-------------------------------+
1036                                                  |
1037                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1038                                                               _fingerprint
1039                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1040  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1041  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1042          |                |                                                             |                 |
1043          |                |  (_cds_entry_table: CODE)                                   |                 |
1044          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1045          |                |                               (allocated at run time)       |                 |
1046          |                |  ...                           [asm code ...]               |                 |
1047          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1048          |                                                                              |                 |
1049          |                                                                              |                 |
1050          +-[compiled]-------------------------------------------------------------------+                 |
1051                                                                                                           |
1052  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1053                                     [jmp c2i_entry] ------------------------------------------------------+
1054 
1055 ***/
1056 
1057 // Called when the method_holder is getting linked. Setup entrypoints so the method
1058 // is ready to be called from interpreter, compiler, and vtables.
1059 void Method::link_method(const methodHandle& h_method, TRAPS) {
1060   // If the code cache is full, we may reenter this function for the
1061   // leftover methods that weren't linked.
1062   if (is_shared()) {
1063     address entry = Interpreter::entry_for_cds_method(h_method);
1064     assert(entry != NULL && entry == _i2i_entry,
1065            "should be correctly set during dump time");
1066     if (adapter() != NULL) {
1067       return;
1068     }
1069     assert(entry == _from_interpreted_entry,
1070            "should be correctly set during dump time");
1071   } else if (_i2i_entry != NULL) {
1072     return;
1073   }
1074   assert( _code == NULL, "nothing compiled yet" );
1075 
1076   // Setup interpreter entrypoint
1077   assert(this == h_method(), "wrong h_method()" );
1078 
1079   if (!is_shared()) {
1080     assert(adapter() == NULL, "init'd to NULL");
1081     address entry = Interpreter::entry_for_method(h_method);
1082     assert(entry != NULL, "interpreter entry must be non-null");
1083     // Sets both _i2i_entry and _from_interpreted_entry
1084     set_interpreter_entry(entry);
1085   }
1086 
1087   // Don't overwrite already registered native entries.
1088   if (is_native() && !has_native_function()) {
1089     set_native_function(
1090       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1091       !native_bind_event_is_interesting);
1092   }
1093 
1094   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1095   // special handling of vtables.  An alternative is to make adapters more
1096   // lazily by calling make_adapter() from from_compiled_entry() for the
1097   // normal calls.  For vtable calls life gets more complicated.  When a
1098   // call-site goes mega-morphic we need adapters in all methods which can be
1099   // called from the vtable.  We need adapters on such methods that get loaded
1100   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1101   // problem we'll make these lazily later.
1102   (void) make_adapters(h_method, CHECK);
1103 
1104   // ONLY USE the h_method now as make_adapter may have blocked
1105 
1106 }
1107 
1108 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1109   // Adapters for compiled code are made eagerly here.  They are fairly
1110   // small (generally < 100 bytes) and quick to make (and cached and shared)
1111   // so making them eagerly shouldn't be too expensive.
1112   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh, CHECK_0);
1113   if (adapter == NULL ) {
1114     if (!is_init_completed()) {
1115       // Don't throw exceptions during VM initialization because java.lang.* classes
1116       // might not have been initialized, causing problems when constructing the
1117       // Java exception object.
1118       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1119     } else {
1120       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1121     }
1122   }
1123 
1124   if (mh->is_shared()) {
1125     assert(mh->adapter() == adapter, "must be");
1126     assert(mh->_from_compiled_entry != NULL, "must be");
1127   } else {
1128     mh->set_adapter_entry(adapter);
1129     mh->_from_compiled_entry = adapter->get_c2i_entry();
1130   }
1131   return adapter->get_c2i_entry();
1132 }
1133 
1134 void Method::restore_unshareable_info(TRAPS) {
1135   assert(is_method() && is_valid_method(), "ensure C++ vtable is restored");
1136 
1137   // Since restore_unshareable_info can be called more than once for a method, don't
1138   // redo any work.
1139   if (adapter() == NULL) {
1140     methodHandle mh(THREAD, this);
1141     link_method(mh, CHECK);
1142   }
1143 }
1144 
1145 address Method::from_compiled_entry_no_trampoline() const {
1146   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1147   if (code) {
1148     return code->verified_entry_point();
1149   } else {
1150     return adapter()->get_c2i_entry();
1151   }
1152 }
1153 
1154 // The verified_code_entry() must be called when a invoke is resolved
1155 // on this method.
1156 
1157 // It returns the compiled code entry point, after asserting not null.
1158 // This function is called after potential safepoints so that nmethod
1159 // or adapter that it points to is still live and valid.
1160 // This function must not hit a safepoint!
1161 address Method::verified_code_entry() {
1162   debug_only(NoSafepointVerifier nsv;)
1163   assert(_from_compiled_entry != NULL, "must be set");
1164   return _from_compiled_entry;
1165 }
1166 
1167 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1168 // (could be racing a deopt).
1169 // Not inline to avoid circular ref.
1170 bool Method::check_code() const {
1171   // cached in a register or local.  There's a race on the value of the field.
1172   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1173   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1174 }
1175 
1176 // Install compiled code.  Instantly it can execute.
1177 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1178   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1179   assert( code, "use clear_code to remove code" );
1180   assert( mh->check_code(), "" );
1181 
1182   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1183 
1184   // These writes must happen in this order, because the interpreter will
1185   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1186   // which jumps to _from_compiled_entry.
1187   mh->_code = code;             // Assign before allowing compiled code to exec
1188 
1189   int comp_level = code->comp_level();
1190   // In theory there could be a race here. In practice it is unlikely
1191   // and not worth worrying about.
1192   if (comp_level > mh->highest_comp_level()) {
1193     mh->set_highest_comp_level(comp_level);
1194   }
1195 
1196   OrderAccess::storestore();
1197   mh->_from_compiled_entry = code->verified_entry_point();
1198   OrderAccess::storestore();
1199   // Instantly compiled code can execute.
1200   if (!mh->is_method_handle_intrinsic())
1201     mh->_from_interpreted_entry = mh->get_i2c_entry();
1202 }
1203 
1204 
1205 bool Method::is_overridden_in(Klass* k) const {
1206   InstanceKlass* ik = InstanceKlass::cast(k);
1207 
1208   if (ik->is_interface()) return false;
1209 
1210   // If method is an interface, we skip it - except if it
1211   // is a miranda method
1212   if (method_holder()->is_interface()) {
1213     // Check that method is not a miranda method
1214     if (ik->lookup_method(name(), signature()) == NULL) {
1215       // No implementation exist - so miranda method
1216       return false;
1217     }
1218     return true;
1219   }
1220 
1221   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1222   if (!has_vtable_index()) {
1223     return false;
1224   } else {
1225     Method* vt_m = ik->method_at_vtable(vtable_index());
1226     return vt_m != this;
1227   }
1228 }
1229 
1230 
1231 // give advice about whether this Method* should be cached or not
1232 bool Method::should_not_be_cached() const {
1233   if (is_old()) {
1234     // This method has been redefined. It is either EMCP or obsolete
1235     // and we don't want to cache it because that would pin the method
1236     // down and prevent it from being collectible if and when it
1237     // finishes executing.
1238     return true;
1239   }
1240 
1241   // caching this method should be just fine
1242   return false;
1243 }
1244 
1245 
1246 /**
1247  *  Returns true if this is one of the specially treated methods for
1248  *  security related stack walks (like Reflection.getCallerClass).
1249  */
1250 bool Method::is_ignored_by_security_stack_walk() const {
1251   if (intrinsic_id() == vmIntrinsics::_invoke) {
1252     // This is Method.invoke() -- ignore it
1253     return true;
1254   }
1255   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1256     // This is an auxilary frame -- ignore it
1257     return true;
1258   }
1259   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1260     // This is an internal adapter frame for method handles -- ignore it
1261     return true;
1262   }
1263   return false;
1264 }
1265 
1266 
1267 // Constant pool structure for invoke methods:
1268 enum {
1269   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1270   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1271   _imcp_limit
1272 };
1273 
1274 // Test if this method is an MH adapter frame generated by Java code.
1275 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1276 bool Method::is_compiled_lambda_form() const {
1277   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1278 }
1279 
1280 // Test if this method is an internal MH primitive method.
1281 bool Method::is_method_handle_intrinsic() const {
1282   vmIntrinsics::ID iid = intrinsic_id();
1283   return (MethodHandles::is_signature_polymorphic(iid) &&
1284           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1285 }
1286 
1287 bool Method::has_member_arg() const {
1288   vmIntrinsics::ID iid = intrinsic_id();
1289   return (MethodHandles::is_signature_polymorphic(iid) &&
1290           MethodHandles::has_member_arg(iid));
1291 }
1292 
1293 // Make an instance of a signature-polymorphic internal MH primitive.
1294 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1295                                                          Symbol* signature,
1296                                                          TRAPS) {
1297   ResourceMark rm;
1298   methodHandle empty;
1299 
1300   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1301   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1302   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1303   if (TraceMethodHandles) {
1304     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1305   }
1306 
1307   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1308   name->increment_refcount();
1309   signature->increment_refcount();
1310 
1311   int cp_length = _imcp_limit;
1312   ClassLoaderData* loader_data = holder->class_loader_data();
1313   constantPoolHandle cp;
1314   {
1315     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1316     cp = constantPoolHandle(THREAD, cp_oop);
1317   }
1318   cp->set_pool_holder(holder);
1319   cp->symbol_at_put(_imcp_invoke_name,       name);
1320   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1321   cp->set_has_preresolution();
1322 
1323   // decide on access bits:  public or not?
1324   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1325   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1326   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1327   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1328 
1329   methodHandle m;
1330   {
1331     InlineTableSizes sizes;
1332     Method* m_oop = Method::allocate(loader_data, 0,
1333                                      accessFlags_from(flags_bits), &sizes,
1334                                      ConstMethod::NORMAL, CHECK_(empty));
1335     m = methodHandle(THREAD, m_oop);
1336   }
1337   m->set_constants(cp());
1338   m->set_name_index(_imcp_invoke_name);
1339   m->set_signature_index(_imcp_invoke_signature);
1340   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1341   assert(m->signature() == signature, "");
1342   ResultTypeFinder rtf(signature);
1343   m->constMethod()->set_result_type(rtf.type());
1344   m->compute_size_of_parameters(THREAD);
1345   m->init_intrinsic_id();
1346   assert(m->is_method_handle_intrinsic(), "");
1347 #ifdef ASSERT
1348   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1349   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1350   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1351 #endif //ASSERT
1352 
1353   // Finally, set up its entry points.
1354   assert(m->can_be_statically_bound(), "");
1355   m->set_vtable_index(Method::nonvirtual_vtable_index);
1356   m->link_method(m, CHECK_(empty));
1357 
1358   if (TraceMethodHandles && (Verbose || WizardMode)) {
1359     ttyLocker ttyl;
1360     m->print_on(tty);
1361   }
1362 
1363   return m;
1364 }
1365 
1366 Klass* Method::check_non_bcp_klass(Klass* klass) {
1367   if (klass != NULL && klass->class_loader() != NULL) {
1368     if (klass->is_objArray_klass())
1369       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1370     return klass;
1371   }
1372   return NULL;
1373 }
1374 
1375 
1376 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1377                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1378   // Code below does not work for native methods - they should never get rewritten anyway
1379   assert(!m->is_native(), "cannot rewrite native methods");
1380   // Allocate new Method*
1381   AccessFlags flags = m->access_flags();
1382 
1383   ConstMethod* cm = m->constMethod();
1384   int checked_exceptions_len = cm->checked_exceptions_length();
1385   int localvariable_len = cm->localvariable_table_length();
1386   int exception_table_len = cm->exception_table_length();
1387   int method_parameters_len = cm->method_parameters_length();
1388   int method_annotations_len = cm->method_annotations_length();
1389   int parameter_annotations_len = cm->parameter_annotations_length();
1390   int type_annotations_len = cm->type_annotations_length();
1391   int default_annotations_len = cm->default_annotations_length();
1392 
1393   InlineTableSizes sizes(
1394       localvariable_len,
1395       new_compressed_linenumber_size,
1396       exception_table_len,
1397       checked_exceptions_len,
1398       method_parameters_len,
1399       cm->generic_signature_index(),
1400       method_annotations_len,
1401       parameter_annotations_len,
1402       type_annotations_len,
1403       default_annotations_len,
1404       0);
1405 
1406   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1407   Method* newm_oop = Method::allocate(loader_data,
1408                                       new_code_length,
1409                                       flags,
1410                                       &sizes,
1411                                       m->method_type(),
1412                                       CHECK_(methodHandle()));
1413   methodHandle newm (THREAD, newm_oop);
1414 
1415   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1416   ConstMethod* newcm = newm->constMethod();
1417   int new_const_method_size = newm->constMethod()->size();
1418 
1419   // This works because the source and target are both Methods. Some compilers
1420   // (e.g., clang) complain that the target vtable pointer will be stomped,
1421   // so cast away newm()'s and m()'s Methodness.
1422   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1423 
1424   // Create shallow copy of ConstMethod.
1425   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1426 
1427   // Reset correct method/const method, method size, and parameter info
1428   newm->set_constMethod(newcm);
1429   newm->constMethod()->set_code_size(new_code_length);
1430   newm->constMethod()->set_constMethod_size(new_const_method_size);
1431   assert(newm->code_size() == new_code_length, "check");
1432   assert(newm->method_parameters_length() == method_parameters_len, "check");
1433   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1434   assert(newm->exception_table_length() == exception_table_len, "check");
1435   assert(newm->localvariable_table_length() == localvariable_len, "check");
1436   // Copy new byte codes
1437   memcpy(newm->code_base(), new_code, new_code_length);
1438   // Copy line number table
1439   if (new_compressed_linenumber_size > 0) {
1440     memcpy(newm->compressed_linenumber_table(),
1441            new_compressed_linenumber_table,
1442            new_compressed_linenumber_size);
1443   }
1444   // Copy method_parameters
1445   if (method_parameters_len > 0) {
1446     memcpy(newm->method_parameters_start(),
1447            m->method_parameters_start(),
1448            method_parameters_len * sizeof(MethodParametersElement));
1449   }
1450   // Copy checked_exceptions
1451   if (checked_exceptions_len > 0) {
1452     memcpy(newm->checked_exceptions_start(),
1453            m->checked_exceptions_start(),
1454            checked_exceptions_len * sizeof(CheckedExceptionElement));
1455   }
1456   // Copy exception table
1457   if (exception_table_len > 0) {
1458     memcpy(newm->exception_table_start(),
1459            m->exception_table_start(),
1460            exception_table_len * sizeof(ExceptionTableElement));
1461   }
1462   // Copy local variable number table
1463   if (localvariable_len > 0) {
1464     memcpy(newm->localvariable_table_start(),
1465            m->localvariable_table_start(),
1466            localvariable_len * sizeof(LocalVariableTableElement));
1467   }
1468   // Copy stackmap table
1469   if (m->has_stackmap_table()) {
1470     int code_attribute_length = m->stackmap_data()->length();
1471     Array<u1>* stackmap_data =
1472       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1473     memcpy((void*)stackmap_data->adr_at(0),
1474            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1475     newm->set_stackmap_data(stackmap_data);
1476   }
1477 
1478   // copy annotations over to new method
1479   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1480   return newm;
1481 }
1482 
1483 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1484   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1485   // because we are not loading from core libraries
1486   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1487   // which does not use the class default class loader so we check for its loader here
1488   const InstanceKlass* ik = InstanceKlass::cast(holder);
1489   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1490     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1491   }
1492 
1493   // see if the klass name is well-known:
1494   Symbol* klass_name = ik->name();
1495   return vmSymbols::find_sid(klass_name);
1496 }
1497 
1498 void Method::init_intrinsic_id() {
1499   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1500   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1501   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1502   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1503 
1504   // the klass name is well-known:
1505   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1506   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1507 
1508   // ditto for method and signature:
1509   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1510   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1511       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1512       && name_id == vmSymbols::NO_SID) {
1513     return;
1514   }
1515   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1516   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1517       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1518       && sig_id == vmSymbols::NO_SID) {
1519     return;
1520   }
1521   jshort flags = access_flags().as_short();
1522 
1523   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1524   if (id != vmIntrinsics::_none) {
1525     set_intrinsic_id(id);
1526     if (id == vmIntrinsics::_Class_cast) {
1527       // Even if the intrinsic is rejected, we want to inline this simple method.
1528       set_force_inline(true);
1529     }
1530     return;
1531   }
1532 
1533   // A few slightly irregular cases:
1534   switch (klass_id) {
1535   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1536     // Second chance: check in regular Math.
1537     switch (name_id) {
1538     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1539     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1540     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1541       // pretend it is the corresponding method in the non-strict class:
1542       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1543       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1544       break;
1545     default:
1546       break;
1547     }
1548     break;
1549 
1550   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1551   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1552   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1553     if (!is_native())  break;
1554     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1555     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1556       id = vmIntrinsics::_none;
1557     break;
1558 
1559   default:
1560     break;
1561   }
1562 
1563   if (id != vmIntrinsics::_none) {
1564     // Set up its iid.  It is an alias method.
1565     set_intrinsic_id(id);
1566     return;
1567   }
1568 }
1569 
1570 // These two methods are static since a GC may move the Method
1571 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1572   if (!THREAD->can_call_java()) {
1573     // There is nothing useful this routine can do from within the Compile thread.
1574     // Hopefully, the signature contains only well-known classes.
1575     // We could scan for this and return true/false, but the caller won't care.
1576     return false;
1577   }
1578   bool sig_is_loaded = true;
1579   Handle class_loader(THREAD, m->method_holder()->class_loader());
1580   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1581   ResourceMark rm(THREAD);
1582   Symbol*  signature = m->signature();
1583   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1584     if (ss.is_object()) {
1585       Symbol* sym = ss.as_symbol(CHECK_(false));
1586       Symbol*  name  = sym;
1587       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1588                                              protection_domain, THREAD);
1589       // We are loading classes eagerly. If a ClassNotFoundException or
1590       // a LinkageError was generated, be sure to ignore it.
1591       if (HAS_PENDING_EXCEPTION) {
1592         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1593             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1594           CLEAR_PENDING_EXCEPTION;
1595         } else {
1596           return false;
1597         }
1598       }
1599       if( klass == NULL) { sig_is_loaded = false; }
1600     }
1601   }
1602   return sig_is_loaded;
1603 }
1604 
1605 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1606   Handle class_loader(THREAD, m->method_holder()->class_loader());
1607   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1608   ResourceMark rm(THREAD);
1609   Symbol*  signature = m->signature();
1610   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1611     if (ss.type() == T_OBJECT) {
1612       Symbol* name = ss.as_symbol_or_null();
1613       if (name == NULL) return true;
1614       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1615       if (klass == NULL) return true;
1616     }
1617   }
1618   return false;
1619 }
1620 
1621 // Exposed so field engineers can debug VM
1622 void Method::print_short_name(outputStream* st) {
1623   ResourceMark rm;
1624 #ifdef PRODUCT
1625   st->print(" %s::", method_holder()->external_name());
1626 #else
1627   st->print(" %s::", method_holder()->internal_name());
1628 #endif
1629   name()->print_symbol_on(st);
1630   if (WizardMode) signature()->print_symbol_on(st);
1631   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1632     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1633 }
1634 
1635 // Comparer for sorting an object array containing
1636 // Method*s.
1637 static int method_comparator(Method* a, Method* b) {
1638   return a->name()->fast_compare(b->name());
1639 }
1640 
1641 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1642 // default_methods also uses this without the ordering for fast find_method
1643 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1644   int length = methods->length();
1645   if (length > 1) {
1646     {
1647       NoSafepointVerifier nsv;
1648       QuickSort::sort(methods->data(), length, method_comparator, idempotent);
1649     }
1650     // Reset method ordering
1651     if (set_idnums) {
1652       for (int i = 0; i < length; i++) {
1653         Method* m = methods->at(i);
1654         m->set_method_idnum(i);
1655         m->set_orig_method_idnum(i);
1656       }
1657     }
1658   }
1659 }
1660 
1661 //-----------------------------------------------------------------------------------
1662 // Non-product code unless JVM/TI needs it
1663 
1664 #if !defined(PRODUCT) || INCLUDE_JVMTI
1665 class SignatureTypePrinter : public SignatureTypeNames {
1666  private:
1667   outputStream* _st;
1668   bool _use_separator;
1669 
1670   void type_name(const char* name) {
1671     if (_use_separator) _st->print(", ");
1672     _st->print("%s", name);
1673     _use_separator = true;
1674   }
1675 
1676  public:
1677   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1678     _st = st;
1679     _use_separator = false;
1680   }
1681 
1682   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1683   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1684 };
1685 
1686 
1687 void Method::print_name(outputStream* st) {
1688   Thread *thread = Thread::current();
1689   ResourceMark rm(thread);
1690   st->print("%s ", is_static() ? "static" : "virtual");
1691   if (WizardMode) {
1692     st->print("%s.", method_holder()->internal_name());
1693     name()->print_symbol_on(st);
1694     signature()->print_symbol_on(st);
1695   } else {
1696     SignatureTypePrinter sig(signature(), st);
1697     sig.print_returntype();
1698     st->print(" %s.", method_holder()->internal_name());
1699     name()->print_symbol_on(st);
1700     st->print("(");
1701     sig.print_parameters();
1702     st->print(")");
1703   }
1704 }
1705 #endif // !PRODUCT || INCLUDE_JVMTI
1706 
1707 
1708 void Method::print_codes_on(outputStream* st) const {
1709   print_codes_on(0, code_size(), st);
1710 }
1711 
1712 void Method::print_codes_on(int from, int to, outputStream* st) const {
1713   Thread *thread = Thread::current();
1714   ResourceMark rm(thread);
1715   methodHandle mh (thread, (Method*)this);
1716   BytecodeStream s(mh);
1717   s.set_interval(from, to);
1718   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1719   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1720 }
1721 
1722 
1723 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1724 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1725 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1726 // as end-of-stream terminator.
1727 
1728 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1729   // bci and line number does not compress into single byte.
1730   // Write out escape character and use regular compression for bci and line number.
1731   write_byte((jubyte)0xFF);
1732   write_signed_int(bci_delta);
1733   write_signed_int(line_delta);
1734 }
1735 
1736 // See comment in method.hpp which explains why this exists.
1737 #if defined(_M_AMD64) && _MSC_VER >= 1400
1738 #pragma optimize("", off)
1739 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1740   write_pair_inline(bci, line);
1741 }
1742 #pragma optimize("", on)
1743 #endif
1744 
1745 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1746   _bci = 0;
1747   _line = 0;
1748 };
1749 
1750 
1751 bool CompressedLineNumberReadStream::read_pair() {
1752   jubyte next = read_byte();
1753   // Check for terminator
1754   if (next == 0) return false;
1755   if (next == 0xFF) {
1756     // Escape character, regular compression used
1757     _bci  += read_signed_int();
1758     _line += read_signed_int();
1759   } else {
1760     // Single byte compression used
1761     _bci  += next >> 3;
1762     _line += next & 0x7;
1763   }
1764   return true;
1765 }
1766 
1767 #if INCLUDE_JVMTI
1768 
1769 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1770   BreakpointInfo* bp = method_holder()->breakpoints();
1771   for (; bp != NULL; bp = bp->next()) {
1772     if (bp->match(this, bci)) {
1773       return bp->orig_bytecode();
1774     }
1775   }
1776   {
1777     ResourceMark rm;
1778     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1779   }
1780   return Bytecodes::_shouldnotreachhere;
1781 }
1782 
1783 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1784   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1785   BreakpointInfo* bp = method_holder()->breakpoints();
1786   for (; bp != NULL; bp = bp->next()) {
1787     if (bp->match(this, bci)) {
1788       bp->set_orig_bytecode(code);
1789       // and continue, in case there is more than one
1790     }
1791   }
1792 }
1793 
1794 void Method::set_breakpoint(int bci) {
1795   InstanceKlass* ik = method_holder();
1796   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1797   bp->set_next(ik->breakpoints());
1798   ik->set_breakpoints(bp);
1799   // do this last:
1800   bp->set(this);
1801 }
1802 
1803 static void clear_matches(Method* m, int bci) {
1804   InstanceKlass* ik = m->method_holder();
1805   BreakpointInfo* prev_bp = NULL;
1806   BreakpointInfo* next_bp;
1807   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1808     next_bp = bp->next();
1809     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1810     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1811       // do this first:
1812       bp->clear(m);
1813       // unhook it
1814       if (prev_bp != NULL)
1815         prev_bp->set_next(next_bp);
1816       else
1817         ik->set_breakpoints(next_bp);
1818       delete bp;
1819       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1820       // at same location. So we have multiple matching (method_index and bci)
1821       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1822       // breakpoint for clear_breakpoint request and keep all other method versions
1823       // BreakpointInfo for future clear_breakpoint request.
1824       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1825       // which is being called when class is unloaded. We delete all the Breakpoint
1826       // information for all versions of method. We may not correctly restore the original
1827       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1828       // so these methods won't be used anymore.
1829       if (bci >= 0) {
1830         break;
1831       }
1832     } else {
1833       // This one is a keeper.
1834       prev_bp = bp;
1835     }
1836   }
1837 }
1838 
1839 void Method::clear_breakpoint(int bci) {
1840   assert(bci >= 0, "");
1841   clear_matches(this, bci);
1842 }
1843 
1844 void Method::clear_all_breakpoints() {
1845   clear_matches(this, -1);
1846 }
1847 
1848 #endif // INCLUDE_JVMTI
1849 
1850 int Method::invocation_count() {
1851   MethodCounters *mcs = method_counters();
1852   if (TieredCompilation) {
1853     MethodData* const mdo = method_data();
1854     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1855         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1856       return InvocationCounter::count_limit;
1857     } else {
1858       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1859              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1860     }
1861   } else {
1862     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1863   }
1864 }
1865 
1866 int Method::backedge_count() {
1867   MethodCounters *mcs = method_counters();
1868   if (TieredCompilation) {
1869     MethodData* const mdo = method_data();
1870     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1871         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1872       return InvocationCounter::count_limit;
1873     } else {
1874       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1875              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1876     }
1877   } else {
1878     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1879   }
1880 }
1881 
1882 void Method::initialize_max_vt_buffer() {
1883   long long max_entries = constMethod()->max_locals() + constMethod()->max_stack();
1884   max_entries *= 2; // Add margin for loops
1885   long long max_size = max_entries * (BigValueTypeThreshold + 8); // 8 -> header size
1886   int max_chunks = (int)(max_size / VTBufferChunk::max_alloc_size()) + 1;
1887   set_max_vt_buffer(MAX2(MinimumVTBufferChunkPerFrame, max_chunks));
1888 }
1889 
1890 int Method::highest_comp_level() const {
1891   const MethodCounters* mcs = method_counters();
1892   if (mcs != NULL) {
1893     return mcs->highest_comp_level();
1894   } else {
1895     return CompLevel_none;
1896   }
1897 }
1898 
1899 int Method::highest_osr_comp_level() const {
1900   const MethodCounters* mcs = method_counters();
1901   if (mcs != NULL) {
1902     return mcs->highest_osr_comp_level();
1903   } else {
1904     return CompLevel_none;
1905   }
1906 }
1907 
1908 void Method::set_highest_comp_level(int level) {
1909   MethodCounters* mcs = method_counters();
1910   if (mcs != NULL) {
1911     mcs->set_highest_comp_level(level);
1912   }
1913 }
1914 
1915 void Method::set_highest_osr_comp_level(int level) {
1916   MethodCounters* mcs = method_counters();
1917   if (mcs != NULL) {
1918     mcs->set_highest_osr_comp_level(level);
1919   }
1920 }
1921 
1922 #if INCLUDE_JVMTI
1923 
1924 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1925   _bci = bci;
1926   _name_index = m->name_index();
1927   _signature_index = m->signature_index();
1928   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1929   if (_orig_bytecode == Bytecodes::_breakpoint)
1930     _orig_bytecode = m->orig_bytecode_at(_bci);
1931   _next = NULL;
1932 }
1933 
1934 void BreakpointInfo::set(Method* method) {
1935 #ifdef ASSERT
1936   {
1937     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1938     if (code == Bytecodes::_breakpoint)
1939       code = method->orig_bytecode_at(_bci);
1940     assert(orig_bytecode() == code, "original bytecode must be the same");
1941   }
1942 #endif
1943   Thread *thread = Thread::current();
1944   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1945   method->incr_number_of_breakpoints(thread);
1946   SystemDictionary::notice_modification();
1947   {
1948     // Deoptimize all dependents on this method
1949     HandleMark hm(thread);
1950     methodHandle mh(thread, method);
1951     CodeCache::flush_dependents_on_method(mh);
1952   }
1953 }
1954 
1955 void BreakpointInfo::clear(Method* method) {
1956   *method->bcp_from(_bci) = orig_bytecode();
1957   assert(method->number_of_breakpoints() > 0, "must not go negative");
1958   method->decr_number_of_breakpoints(Thread::current());
1959 }
1960 
1961 #endif // INCLUDE_JVMTI
1962 
1963 // jmethodID handling
1964 
1965 // This is a block allocating object, sort of like JNIHandleBlock, only a
1966 // lot simpler.
1967 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1968 // never get rid of it.
1969 
1970 static const int min_block_size = 8;
1971 
1972 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1973   friend class JNIMethodBlock;
1974   Method**        _methods;
1975   int             _number_of_methods;
1976   int             _top;
1977   JNIMethodBlockNode* _next;
1978 
1979  public:
1980 
1981   JNIMethodBlockNode(int num_methods = min_block_size);
1982 
1983   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1984 
1985   void ensure_methods(int num_addl_methods) {
1986     if (_top < _number_of_methods) {
1987       num_addl_methods -= _number_of_methods - _top;
1988       if (num_addl_methods <= 0) {
1989         return;
1990       }
1991     }
1992     if (_next == NULL) {
1993       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1994     } else {
1995       _next->ensure_methods(num_addl_methods);
1996     }
1997   }
1998 };
1999 
2000 class JNIMethodBlock : public CHeapObj<mtClass> {
2001   JNIMethodBlockNode _head;
2002   JNIMethodBlockNode *_last_free;
2003  public:
2004   static Method* const _free_method;
2005 
2006   JNIMethodBlock(int initial_capacity = min_block_size)
2007       : _head(initial_capacity), _last_free(&_head) {}
2008 
2009   void ensure_methods(int num_addl_methods) {
2010     _last_free->ensure_methods(num_addl_methods);
2011   }
2012 
2013   Method** add_method(Method* m) {
2014     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2015       if (b->_top < b->_number_of_methods) {
2016         // top points to the next free entry.
2017         int i = b->_top;
2018         b->_methods[i] = m;
2019         b->_top++;
2020         _last_free = b;
2021         return &(b->_methods[i]);
2022       } else if (b->_top == b->_number_of_methods) {
2023         // if the next free entry ran off the block see if there's a free entry
2024         for (int i = 0; i < b->_number_of_methods; i++) {
2025           if (b->_methods[i] == _free_method) {
2026             b->_methods[i] = m;
2027             _last_free = b;
2028             return &(b->_methods[i]);
2029           }
2030         }
2031         // Only check each block once for frees.  They're very unlikely.
2032         // Increment top past the end of the block.
2033         b->_top++;
2034       }
2035       // need to allocate a next block.
2036       if (b->_next == NULL) {
2037         b->_next = _last_free = new JNIMethodBlockNode();
2038       }
2039     }
2040     guarantee(false, "Should always allocate a free block");
2041     return NULL;
2042   }
2043 
2044   bool contains(Method** m) {
2045     if (m == NULL) return false;
2046     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2047       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2048         // This is a bit of extra checking, for two reasons.  One is
2049         // that contains() deals with pointers that are passed in by
2050         // JNI code, so making sure that the pointer is aligned
2051         // correctly is valuable.  The other is that <= and > are
2052         // technically not defined on pointers, so the if guard can
2053         // pass spuriously; no modern compiler is likely to make that
2054         // a problem, though (and if one did, the guard could also
2055         // fail spuriously, which would be bad).
2056         ptrdiff_t idx = m - b->_methods;
2057         if (b->_methods + idx == m) {
2058           return true;
2059         }
2060       }
2061     }
2062     return false;  // not found
2063   }
2064 
2065   // Doesn't really destroy it, just marks it as free so it can be reused.
2066   void destroy_method(Method** m) {
2067 #ifdef ASSERT
2068     assert(contains(m), "should be a methodID");
2069 #endif // ASSERT
2070     *m = _free_method;
2071   }
2072 
2073   // During class unloading the methods are cleared, which is different
2074   // than freed.
2075   void clear_all_methods() {
2076     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2077       for (int i = 0; i< b->_number_of_methods; i++) {
2078         b->_methods[i] = NULL;
2079       }
2080     }
2081   }
2082 #ifndef PRODUCT
2083   int count_methods() {
2084     // count all allocated methods
2085     int count = 0;
2086     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2087       for (int i = 0; i< b->_number_of_methods; i++) {
2088         if (b->_methods[i] != _free_method) count++;
2089       }
2090     }
2091     return count;
2092   }
2093 #endif // PRODUCT
2094 };
2095 
2096 // Something that can't be mistaken for an address or a markOop
2097 Method* const JNIMethodBlock::_free_method = (Method*)55;
2098 
2099 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
2100   _number_of_methods = MAX2(num_methods, min_block_size);
2101   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2102   for (int i = 0; i < _number_of_methods; i++) {
2103     _methods[i] = JNIMethodBlock::_free_method;
2104   }
2105 }
2106 
2107 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2108   ClassLoaderData* cld = loader_data;
2109   if (!SafepointSynchronize::is_at_safepoint()) {
2110     // Have to add jmethod_ids() to class loader data thread-safely.
2111     // Also have to add the method to the list safely, which the cld lock
2112     // protects as well.
2113     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2114     if (cld->jmethod_ids() == NULL) {
2115       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2116     } else {
2117       cld->jmethod_ids()->ensure_methods(capacity);
2118     }
2119   } else {
2120     // At safepoint, we are single threaded and can set this.
2121     if (cld->jmethod_ids() == NULL) {
2122       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2123     } else {
2124       cld->jmethod_ids()->ensure_methods(capacity);
2125     }
2126   }
2127 }
2128 
2129 // Add a method id to the jmethod_ids
2130 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2131   ClassLoaderData* cld = loader_data;
2132 
2133   if (!SafepointSynchronize::is_at_safepoint()) {
2134     // Have to add jmethod_ids() to class loader data thread-safely.
2135     // Also have to add the method to the list safely, which the cld lock
2136     // protects as well.
2137     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2138     if (cld->jmethod_ids() == NULL) {
2139       cld->set_jmethod_ids(new JNIMethodBlock());
2140     }
2141     // jmethodID is a pointer to Method*
2142     return (jmethodID)cld->jmethod_ids()->add_method(m);
2143   } else {
2144     // At safepoint, we are single threaded and can set this.
2145     if (cld->jmethod_ids() == NULL) {
2146       cld->set_jmethod_ids(new JNIMethodBlock());
2147     }
2148     // jmethodID is a pointer to Method*
2149     return (jmethodID)cld->jmethod_ids()->add_method(m);
2150   }
2151 }
2152 
2153 // Mark a jmethodID as free.  This is called when there is a data race in
2154 // InstanceKlass while creating the jmethodID cache.
2155 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2156   ClassLoaderData* cld = loader_data;
2157   Method** ptr = (Method**)m;
2158   assert(cld->jmethod_ids() != NULL, "should have method handles");
2159   cld->jmethod_ids()->destroy_method(ptr);
2160 }
2161 
2162 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2163   // Can't assert the method_holder is the same because the new method has the
2164   // scratch method holder.
2165   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2166            == new_method->method_holder()->class_loader(),
2167          "changing to a different class loader");
2168   // Just change the method in place, jmethodID pointer doesn't change.
2169   *((Method**)jmid) = new_method;
2170 }
2171 
2172 bool Method::is_method_id(jmethodID mid) {
2173   Method* m = resolve_jmethod_id(mid);
2174   assert(m != NULL, "should be called with non-null method");
2175   InstanceKlass* ik = m->method_holder();
2176   ClassLoaderData* cld = ik->class_loader_data();
2177   if (cld->jmethod_ids() == NULL) return false;
2178   return (cld->jmethod_ids()->contains((Method**)mid));
2179 }
2180 
2181 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2182   if (mid == NULL) return NULL;
2183   Method* o = resolve_jmethod_id(mid);
2184   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2185     return NULL;
2186   }
2187   return o;
2188 };
2189 
2190 void Method::set_on_stack(const bool value) {
2191   // Set both the method itself and its constant pool.  The constant pool
2192   // on stack means some method referring to it is also on the stack.
2193   constants()->set_on_stack(value);
2194 
2195   bool already_set = on_stack();
2196   _access_flags.set_on_stack(value);
2197   if (value && !already_set) {
2198     MetadataOnStackMark::record(this);
2199   }
2200 }
2201 
2202 // Called when the class loader is unloaded to make all methods weak.
2203 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2204   loader_data->jmethod_ids()->clear_all_methods();
2205 }
2206 
2207 bool Method::has_method_vptr(const void* ptr) {
2208   Method m;
2209   // This assumes that the vtbl pointer is the first word of a C++ object.
2210   return dereference_vptr(&m) == dereference_vptr(ptr);
2211 }
2212 
2213 // Check that this pointer is valid by checking that the vtbl pointer matches
2214 bool Method::is_valid_method() const {
2215   if (this == NULL) {
2216     return false;
2217   } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2218     // Quick sanity check on pointer.
2219     return false;
2220   } else if (is_shared()) {
2221     return MetaspaceShared::is_valid_shared_method(this);
2222   } else if (Metaspace::contains_non_shared(this)) {
2223     return has_method_vptr((const void*)this);
2224   } else {
2225     return false;
2226   }
2227 }
2228 
2229 #ifndef PRODUCT
2230 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2231   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2232 }
2233 #endif // PRODUCT
2234 
2235 
2236 // Printing
2237 
2238 #ifndef PRODUCT
2239 
2240 void Method::print_on(outputStream* st) const {
2241   ResourceMark rm;
2242   assert(is_method(), "must be method");
2243   st->print_cr("%s", internal_name());
2244   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2245   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2246   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2247   constants()->print_value_on(st); st->cr();
2248   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2249   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2250   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2251   st->print_cr(" - max stack:         %d",   max_stack());
2252   st->print_cr(" - max locals:        %d",   max_locals());
2253   st->print_cr(" - size of params:    %d",   size_of_parameters());
2254   st->print_cr(" - method size:       %d",   method_size());
2255   if (intrinsic_id() != vmIntrinsics::_none)
2256     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2257   if (highest_comp_level() != CompLevel_none)
2258     st->print_cr(" - highest level:     %d", highest_comp_level());
2259   st->print_cr(" - vtable index:      %d",   _vtable_index);
2260   if (valid_itable_index())
2261     st->print_cr(" - itable index:      %d",   itable_index());
2262   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2263   st->print(   " - adapters:          ");
2264   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2265   if (a == NULL)
2266     st->print_cr(INTPTR_FORMAT, p2i(a));
2267   else
2268     a->print_adapter_on(st);
2269   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2270   st->print_cr(" - code size:         %d",   code_size());
2271   if (code_size() != 0) {
2272     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2273     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2274   }
2275   if (method_data() != NULL) {
2276     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2277   }
2278   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2279   if (checked_exceptions_length() > 0) {
2280     CheckedExceptionElement* table = checked_exceptions_start();
2281     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2282     if (Verbose) {
2283       for (int i = 0; i < checked_exceptions_length(); i++) {
2284         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2285       }
2286     }
2287   }
2288   if (has_linenumber_table()) {
2289     u_char* table = compressed_linenumber_table();
2290     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2291     if (Verbose) {
2292       CompressedLineNumberReadStream stream(table);
2293       while (stream.read_pair()) {
2294         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2295       }
2296     }
2297   }
2298   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2299   if (localvariable_table_length() > 0) {
2300     LocalVariableTableElement* table = localvariable_table_start();
2301     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2302     if (Verbose) {
2303       for (int i = 0; i < localvariable_table_length(); i++) {
2304         int bci = table[i].start_bci;
2305         int len = table[i].length;
2306         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2307         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2308         int slot = table[i].slot;
2309         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2310       }
2311     }
2312   }
2313   if (code() != NULL) {
2314     st->print   (" - compiled code: ");
2315     code()->print_value_on(st);
2316   }
2317   if (is_native()) {
2318     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2319     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2320   }
2321 }
2322 
2323 void Method::print_linkage_flags(outputStream* st) {
2324   access_flags().print_on(st);
2325   if (is_default_method()) {
2326     st->print("default ");
2327   }
2328   if (is_overpass()) {
2329     st->print("overpass ");
2330   }
2331 }
2332 #endif //PRODUCT
2333 
2334 void Method::print_value_on(outputStream* st) const {
2335   assert(is_method(), "must be method");
2336   st->print("%s", internal_name());
2337   print_address_on(st);
2338   st->print(" ");
2339   if (WizardMode) access_flags().print_on(st);
2340   name()->print_value_on(st);
2341   st->print(" ");
2342   signature()->print_value_on(st);
2343   st->print(" in ");
2344   method_holder()->print_value_on(st);
2345   if (WizardMode) st->print("#%d", _vtable_index);
2346   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2347   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2348 }
2349 
2350 #if INCLUDE_SERVICES
2351 // Size Statistics
2352 void Method::collect_statistics(KlassSizeStats *sz) const {
2353   int mysize = sz->count(this);
2354   sz->_method_bytes += mysize;
2355   sz->_method_all_bytes += mysize;
2356   sz->_rw_bytes += mysize;
2357 
2358   if (constMethod()) {
2359     constMethod()->collect_statistics(sz);
2360   }
2361   if (method_data()) {
2362     method_data()->collect_statistics(sz);
2363   }
2364 }
2365 #endif // INCLUDE_SERVICES
2366 
2367 // LogTouchedMethods and PrintTouchedMethods
2368 
2369 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2370 // the Method may be garbage collected. Let's roll our own hash table.
2371 class TouchedMethodRecord : CHeapObj<mtTracing> {
2372 public:
2373   // It's OK to store Symbols here because they will NOT be GC'ed if
2374   // LogTouchedMethods is enabled.
2375   TouchedMethodRecord* _next;
2376   Symbol* _class_name;
2377   Symbol* _method_name;
2378   Symbol* _method_signature;
2379 };
2380 
2381 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2382 static TouchedMethodRecord** _touched_method_table = NULL;
2383 
2384 void Method::log_touched(TRAPS) {
2385 
2386   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2387   Symbol* my_class = klass_name();
2388   Symbol* my_name  = name();
2389   Symbol* my_sig   = signature();
2390 
2391   unsigned int hash = my_class->identity_hash() +
2392                       my_name->identity_hash() +
2393                       my_sig->identity_hash();
2394   juint index = juint(hash) % table_size;
2395 
2396   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2397   if (_touched_method_table == NULL) {
2398     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2399                                               mtTracing, CURRENT_PC);
2400     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2401   }
2402 
2403   TouchedMethodRecord* ptr = _touched_method_table[index];
2404   while (ptr) {
2405     if (ptr->_class_name       == my_class &&
2406         ptr->_method_name      == my_name &&
2407         ptr->_method_signature == my_sig) {
2408       return;
2409     }
2410     if (ptr->_next == NULL) break;
2411     ptr = ptr->_next;
2412   }
2413   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2414   my_class->set_permanent();  // prevent reclaimed by GC
2415   my_name->set_permanent();
2416   my_sig->set_permanent();
2417   nptr->_class_name         = my_class;
2418   nptr->_method_name        = my_name;
2419   nptr->_method_signature   = my_sig;
2420   nptr->_next               = NULL;
2421 
2422   if (ptr == NULL) {
2423     // first
2424     _touched_method_table[index] = nptr;
2425   } else {
2426     ptr->_next = nptr;
2427   }
2428 }
2429 
2430 void Method::print_touched_methods(outputStream* out) {
2431   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2432   out->print_cr("# Method::print_touched_methods version 1");
2433   if (_touched_method_table) {
2434     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2435       TouchedMethodRecord* ptr = _touched_method_table[i];
2436       while(ptr) {
2437         ptr->_class_name->print_symbol_on(out);       out->print(".");
2438         ptr->_method_name->print_symbol_on(out);      out->print(":");
2439         ptr->_method_signature->print_symbol_on(out); out->cr();
2440         ptr = ptr->_next;
2441       }
2442     }
2443   }
2444 }
2445 
2446 // Verification
2447 
2448 void Method::verify_on(outputStream* st) {
2449   guarantee(is_method(), "object must be method");
2450   guarantee(constants()->is_constantPool(), "should be constant pool");
2451   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2452   MethodData* md = method_data();
2453   guarantee(md == NULL ||
2454       md->is_methodData(), "should be method data");
2455 }