1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "gc/shared/collectedHeap.inline.hpp"
  31 #include "interpreter/bytecodeStream.hpp"
  32 #include "interpreter/bytecodeTracer.hpp"
  33 #include "interpreter/bytecodes.hpp"
  34 #include "interpreter/interpreter.hpp"
  35 #include "interpreter/oopMapCache.hpp"
  36 #include "memory/allocation.inline.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/metaspaceClosure.hpp"
  40 #include "memory/metaspaceShared.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "memory/vtBuffer.hpp"
  44 #include "oops/constMethod.hpp"
  45 #include "oops/method.inline.hpp"
  46 #include "oops/methodData.hpp"
  47 #include "oops/objArrayOop.inline.hpp"
  48 #include "oops/oop.inline.hpp"
  49 #include "oops/symbol.hpp"
  50 #include "oops/valueKlass.hpp"
  51 #include "prims/jvmtiExport.hpp"
  52 #include "prims/methodHandles.hpp"
  53 #include "prims/nativeLookup.hpp"
  54 #include "runtime/arguments.hpp"
  55 #include "runtime/compilationPolicy.hpp"
  56 #include "runtime/frame.inline.hpp"
  57 #include "runtime/handles.inline.hpp"
  58 #include "runtime/init.hpp"
  59 #include "runtime/orderAccess.hpp"
  60 #include "runtime/relocator.hpp"
  61 #include "runtime/safepointVerifiers.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 int Method::extra_stack_words() {
 457   // not an inline function, to avoid a header dependency on Interpreter
 458   return extra_stack_entries() * Interpreter::stackElementSize;
 459 }
 460 
 461 
 462 void Method::compute_size_of_parameters(Thread *thread) {
 463   ArgumentSizeComputer asc(signature());
 464   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 465 }
 466 
 467 BasicType Method::result_type() const {
 468   ResultTypeFinder rtf(signature());
 469   return rtf.type();
 470 }
 471 
 472 #ifdef ASSERT
 473 // ValueKlass the method is declared to return. This must not
 474 // safepoint as it is called with references live on the stack at
 475 // locations the GC is unaware of.
 476 ValueKlass* Method::returned_value_type(Thread* thread) const {
 477   assert(is_returning_vt(), "method return type should be value type");
 478   SignatureStream ss(signature());
 479   while (!ss.at_return_type()) {
 480     ss.next();
 481   }
 482   Handle class_loader(thread, method_holder()->class_loader());
 483   Handle protection_domain(thread, method_holder()->protection_domain());
 484   Klass* k = NULL;
 485   {
 486     NoSafepointVerifier nsv;
 487     k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
 488   }
 489   assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
 490   return ValueKlass::cast(k);
 491 }
 492 #endif
 493 
 494 bool Method::has_value_args() const {
 495   return adapter()->get_sig_extended() != NULL;
 496 }
 497 
 498 bool Method::is_empty_method() const {
 499   return  code_size() == 1
 500       && *code_base() == Bytecodes::_return;
 501 }
 502 
 503 
 504 bool Method::is_vanilla_constructor() const {
 505   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 506   // which only calls the superclass vanilla constructor and possibly does stores of
 507   // zero constants to local fields:
 508   //
 509   //   aload_0
 510   //   invokespecial
 511   //   indexbyte1
 512   //   indexbyte2
 513   //
 514   // followed by an (optional) sequence of:
 515   //
 516   //   aload_0
 517   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 518   //   putfield
 519   //   indexbyte1
 520   //   indexbyte2
 521   //
 522   // followed by:
 523   //
 524   //   return
 525 
 526   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 527   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 528   int size = code_size();
 529   // Check if size match
 530   if (size == 0 || size % 5 != 0) return false;
 531   address cb = code_base();
 532   int last = size - 1;
 533   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 534     // Does not call superclass default constructor
 535     return false;
 536   }
 537   // Check optional sequence
 538   for (int i = 4; i < last; i += 5) {
 539     if (cb[i] != Bytecodes::_aload_0) return false;
 540     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 541     if (cb[i+2] != Bytecodes::_putfield) return false;
 542   }
 543   return true;
 544 }
 545 
 546 
 547 bool Method::compute_has_loops_flag() {
 548   BytecodeStream bcs(this);
 549   Bytecodes::Code bc;
 550 
 551   while ((bc = bcs.next()) >= 0) {
 552     switch( bc ) {
 553       case Bytecodes::_ifeq:
 554       case Bytecodes::_ifnull:
 555       case Bytecodes::_iflt:
 556       case Bytecodes::_ifle:
 557       case Bytecodes::_ifne:
 558       case Bytecodes::_ifnonnull:
 559       case Bytecodes::_ifgt:
 560       case Bytecodes::_ifge:
 561       case Bytecodes::_if_icmpeq:
 562       case Bytecodes::_if_icmpne:
 563       case Bytecodes::_if_icmplt:
 564       case Bytecodes::_if_icmpgt:
 565       case Bytecodes::_if_icmple:
 566       case Bytecodes::_if_icmpge:
 567       case Bytecodes::_if_acmpeq:
 568       case Bytecodes::_if_acmpne:
 569       case Bytecodes::_goto:
 570       case Bytecodes::_jsr:
 571         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 572         break;
 573 
 574       case Bytecodes::_goto_w:
 575       case Bytecodes::_jsr_w:
 576         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 577         break;
 578 
 579       default:
 580         break;
 581     }
 582   }
 583   _access_flags.set_loops_flag_init();
 584   return _access_flags.has_loops();
 585 }
 586 
 587 bool Method::is_final_method(AccessFlags class_access_flags) const {
 588   // or "does_not_require_vtable_entry"
 589   // default method or overpass can occur, is not final (reuses vtable entry)
 590   // private methods in classes get vtable entries for backward class compatibility.
 591   if (is_overpass() || is_default_method())  return false;
 592   return is_final() || class_access_flags.is_final();
 593 }
 594 
 595 bool Method::is_final_method() const {
 596   return is_final_method(method_holder()->access_flags());
 597 }
 598 
 599 bool Method::is_default_method() const {
 600   if (method_holder() != NULL &&
 601       method_holder()->is_interface() &&
 602       !is_abstract() && !is_private()) {
 603     return true;
 604   } else {
 605     return false;
 606   }
 607 }
 608 
 609 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 610   if (is_final_method(class_access_flags))  return true;
 611 #ifdef ASSERT
 612   ResourceMark rm;
 613   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 614   if (class_access_flags.is_interface()) {
 615       assert(is_nonv == is_static() || is_nonv == is_private(),
 616              "nonvirtual unexpected for non-static, non-private: %s",
 617              name_and_sig_as_C_string());
 618   }
 619 #endif
 620   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 621   return vtable_index() == nonvirtual_vtable_index;
 622 }
 623 
 624 bool Method::can_be_statically_bound() const {
 625   return can_be_statically_bound(method_holder()->access_flags());
 626 }
 627 
 628 bool Method::is_accessor() const {
 629   return is_getter() || is_setter();
 630 }
 631 
 632 bool Method::is_getter() const {
 633   if (code_size() != 5) return false;
 634   if (size_of_parameters() != 1) return false;
 635   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 636   if (java_code_at(1) != Bytecodes::_getfield) return false;
 637   switch (java_code_at(4)) {
 638     case Bytecodes::_ireturn:
 639     case Bytecodes::_lreturn:
 640     case Bytecodes::_freturn:
 641     case Bytecodes::_dreturn:
 642     case Bytecodes::_areturn:
 643       break;
 644     default:
 645       return false;
 646   }
 647   return true;
 648 }
 649 
 650 bool Method::is_setter() const {
 651   if (code_size() != 6) return false;
 652   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 653   switch (java_code_at(1)) {
 654     case Bytecodes::_iload_1:
 655     case Bytecodes::_aload_1:
 656     case Bytecodes::_fload_1:
 657       if (size_of_parameters() != 2) return false;
 658       break;
 659     case Bytecodes::_dload_1:
 660     case Bytecodes::_lload_1:
 661       if (size_of_parameters() != 3) return false;
 662       break;
 663     default:
 664       return false;
 665   }
 666   if (java_code_at(2) != Bytecodes::_putfield) return false;
 667   if (java_code_at(5) != Bytecodes::_return)   return false;
 668   return true;
 669 }
 670 
 671 bool Method::is_constant_getter() const {
 672   int last_index = code_size() - 1;
 673   // Check if the first 1-3 bytecodes are a constant push
 674   // and the last bytecode is a return.
 675   return (2 <= code_size() && code_size() <= 4 &&
 676           Bytecodes::is_const(java_code_at(0)) &&
 677           Bytecodes::length_for(java_code_at(0)) == last_index &&
 678           Bytecodes::is_return(java_code_at(last_index)));
 679 }
 680 
 681 bool Method::is_initializer() const {
 682   return is_object_initializer() || is_static_initializer();
 683 }
 684 
 685 bool Method::has_valid_initializer_flags() const {
 686   return (is_static() ||
 687           method_holder()->major_version() < 51);
 688 }
 689 
 690 bool Method::is_static_initializer() const {
 691   // For classfiles version 51 or greater, ensure that the clinit method is
 692   // static.  Non-static methods with the name "<clinit>" are not static
 693   // initializers. (older classfiles exempted for backward compatibility)
 694   return name() == vmSymbols::class_initializer_name() &&
 695          has_valid_initializer_flags();
 696 }
 697 
 698 bool Method::is_object_initializer() const {
 699    return name() == vmSymbols::object_initializer_name();
 700 }
 701 
 702 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 703   int length = method->checked_exceptions_length();
 704   if (length == 0) {  // common case
 705     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 706   } else {
 707     methodHandle h_this(THREAD, method);
 708     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 709     objArrayHandle mirrors (THREAD, m_oop);
 710     for (int i = 0; i < length; i++) {
 711       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 712       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 713       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 714       mirrors->obj_at_put(i, k->java_mirror());
 715     }
 716     return mirrors;
 717   }
 718 };
 719 
 720 
 721 int Method::line_number_from_bci(int bci) const {
 722   int best_bci  =  0;
 723   int best_line = -1;
 724   if (bci == SynchronizationEntryBCI) bci = 0;
 725   if (0 <= bci && bci < code_size() && has_linenumber_table()) {
 726     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 727     // Not necessarily sorted and not necessarily one-to-one.
 728     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 729     while (stream.read_pair()) {
 730       if (stream.bci() == bci) {
 731         // perfect match
 732         return stream.line();
 733       } else {
 734         // update best_bci/line
 735         if (stream.bci() < bci && stream.bci() >= best_bci) {
 736           best_bci  = stream.bci();
 737           best_line = stream.line();
 738         }
 739       }
 740     }
 741   }
 742   return best_line;
 743 }
 744 
 745 
 746 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 747   if( constants()->tag_at(klass_index).is_unresolved_klass()) {
 748     Thread *thread = Thread::current();
 749     Symbol* klass_name = constants()->klass_name_at(klass_index);
 750     Handle loader(thread, method_holder()->class_loader());
 751     Handle prot  (thread, method_holder()->protection_domain());
 752     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 753   } else {
 754     return true;
 755   }
 756 }
 757 
 758 
 759 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 760   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 761   if (must_be_resolved) {
 762     // Make sure klass is resolved in constantpool.
 763     if (constants()->tag_at(klass_index).is_unresolved_klass()) {
 764       return false;
 765     }
 766   }
 767   return is_klass_loaded_by_klass_index(klass_index);
 768 }
 769 
 770 
 771 void Method::set_native_function(address function, bool post_event_flag) {
 772   assert(function != NULL, "use clear_native_function to unregister natives");
 773   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 774   address* native_function = native_function_addr();
 775 
 776   // We can see racers trying to place the same native function into place. Once
 777   // is plenty.
 778   address current = *native_function;
 779   if (current == function) return;
 780   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 781       function != NULL) {
 782     // native_method_throw_unsatisfied_link_error_entry() should only
 783     // be passed when post_event_flag is false.
 784     assert(function !=
 785       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 786       "post_event_flag mis-match");
 787 
 788     // post the bind event, and possible change the bind function
 789     JvmtiExport::post_native_method_bind(this, &function);
 790   }
 791   *native_function = function;
 792   // This function can be called more than once. We must make sure that we always
 793   // use the latest registered method -> check if a stub already has been generated.
 794   // If so, we have to make it not_entrant.
 795   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 796   if (nm != NULL) {
 797     nm->make_not_entrant();
 798   }
 799 }
 800 
 801 
 802 bool Method::has_native_function() const {
 803   if (is_method_handle_intrinsic())
 804     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 805   address func = native_function();
 806   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 807 }
 808 
 809 
 810 void Method::clear_native_function() {
 811   // Note: is_method_handle_intrinsic() is allowed here.
 812   set_native_function(
 813     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 814     !native_bind_event_is_interesting);
 815   clear_code();
 816 }
 817 
 818 address Method::critical_native_function() {
 819   methodHandle mh(this);
 820   return NativeLookup::lookup_critical_entry(mh);
 821 }
 822 
 823 
 824 void Method::set_signature_handler(address handler) {
 825   address* signature_handler =  signature_handler_addr();
 826   *signature_handler = handler;
 827 }
 828 
 829 
 830 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 831   if (PrintCompilation && report) {
 832     ttyLocker ttyl;
 833     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 834     if (comp_level == CompLevel_all) {
 835       tty->print("all levels ");
 836     } else {
 837       tty->print("levels ");
 838       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 839         tty->print("%d ", i);
 840       }
 841     }
 842     this->print_short_name(tty);
 843     int size = this->code_size();
 844     if (size > 0) {
 845       tty->print(" (%d bytes)", size);
 846     }
 847     if (reason != NULL) {
 848       tty->print("   %s", reason);
 849     }
 850     tty->cr();
 851   }
 852   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 853     ttyLocker ttyl;
 854     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 855                      os::current_thread_id(), is_osr, comp_level);
 856     if (reason != NULL) {
 857       xtty->print(" reason=\'%s\'", reason);
 858     }
 859     xtty->method(this);
 860     xtty->stamp();
 861     xtty->end_elem();
 862   }
 863 }
 864 
 865 bool Method::is_always_compilable() const {
 866   // Generated adapters must be compiled
 867   if (is_method_handle_intrinsic() && is_synthetic()) {
 868     assert(!is_not_c1_compilable(), "sanity check");
 869     assert(!is_not_c2_compilable(), "sanity check");
 870     return true;
 871   }
 872 
 873   return false;
 874 }
 875 
 876 bool Method::is_not_compilable(int comp_level) const {
 877   if (number_of_breakpoints() > 0)
 878     return true;
 879   if (is_always_compilable())
 880     return false;
 881   if (comp_level == CompLevel_any)
 882     return is_not_c1_compilable() || is_not_c2_compilable();
 883   if (is_c1_compile(comp_level))
 884     return is_not_c1_compilable();
 885   if (is_c2_compile(comp_level))
 886     return is_not_c2_compilable();
 887   return false;
 888 }
 889 
 890 // call this when compiler finds that this method is not compilable
 891 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 892   if (is_always_compilable()) {
 893     // Don't mark a method which should be always compilable
 894     return;
 895   }
 896   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 897   if (comp_level == CompLevel_all) {
 898     set_not_c1_compilable();
 899     set_not_c2_compilable();
 900   } else {
 901     if (is_c1_compile(comp_level))
 902       set_not_c1_compilable();
 903     if (is_c2_compile(comp_level))
 904       set_not_c2_compilable();
 905   }
 906   CompilationPolicy::policy()->disable_compilation(this);
 907   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 908 }
 909 
 910 bool Method::is_not_osr_compilable(int comp_level) const {
 911   if (is_not_compilable(comp_level))
 912     return true;
 913   if (comp_level == CompLevel_any)
 914     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 915   if (is_c1_compile(comp_level))
 916     return is_not_c1_osr_compilable();
 917   if (is_c2_compile(comp_level))
 918     return is_not_c2_osr_compilable();
 919   return false;
 920 }
 921 
 922 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 923   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 924   if (comp_level == CompLevel_all) {
 925     set_not_c1_osr_compilable();
 926     set_not_c2_osr_compilable();
 927   } else {
 928     if (is_c1_compile(comp_level))
 929       set_not_c1_osr_compilable();
 930     if (is_c2_compile(comp_level))
 931       set_not_c2_osr_compilable();
 932   }
 933   CompilationPolicy::policy()->disable_compilation(this);
 934   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 935 }
 936 
 937 // Revert to using the interpreter and clear out the nmethod
 938 void Method::clear_code(bool acquire_lock /* = true */) {
 939   MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
 940   // this may be NULL if c2i adapters have not been made yet
 941   // Only should happen at allocate time.
 942   if (adapter() == NULL) {
 943     _from_compiled_entry    = NULL;
 944     _from_compiled_value_entry = NULL;
 945   } else {
 946     _from_compiled_entry    = adapter()->get_c2i_entry();
 947     _from_compiled_value_entry = adapter()->get_c2i_entry();
 948   }
 949   OrderAccess::storestore();
 950   _from_interpreted_entry = _i2i_entry;
 951   OrderAccess::storestore();
 952   _code = NULL;
 953 }
 954 
 955 #if INCLUDE_CDS
 956 // Called by class data sharing to remove any entry points (which are not shared)
 957 void Method::unlink_method() {
 958   _code = NULL;
 959 
 960   assert(DumpSharedSpaces, "dump time only");
 961   // Set the values to what they should be at run time. Note that
 962   // this Method can no longer be executed during dump time.
 963   _i2i_entry = Interpreter::entry_for_cds_method(this);
 964   _from_interpreted_entry = _i2i_entry;
 965 
 966   if (is_native()) {
 967     *native_function_addr() = NULL;
 968     set_signature_handler(NULL);
 969   }
 970   NOT_PRODUCT(set_compiled_invocation_count(0);)
 971 
 972   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 973   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 974   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 975   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 976   _from_compiled_value_entry = cds_adapter->get_c2i_entry_trampoline();
 977   assert(*((int*)_from_compiled_value_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 978 
 979   set_method_data(NULL);
 980   clear_method_counters();
 981 }
 982 #endif
 983 
 984 /****************************************************************************
 985 // The following illustrates how the entries work for CDS shared Methods:
 986 //
 987 // Our goal is to delay writing into a shared Method until it's compiled.
 988 // Hence, we want to determine the initial values for _i2i_entry,
 989 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
 990 //
 991 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
 992 // They also have similar signatures so that they will share the same
 993 // AdapterHandlerEntry.
 994 //
 995 // _adapter_trampoline points to a fixed location in the RW section of
 996 // the CDS archive. This location initially contains a NULL pointer. When the
 997 // first of method A or B is linked, an AdapterHandlerEntry is allocated
 998 // dynamically, and its c2i/i2c entries are generated.
 999 //
1000 // _i2i_entry and _from_interpreted_entry initially points to the same
1001 // (fixed) location in the CODE section of the CDS archive. This contains
1002 // an unconditional branch to the actual entry for "zero_locals", which is
1003 // generated at run time and may be on an arbitrary address. Thus, the
1004 // unconditional branch is also generated at run time to jump to the correct
1005 // address.
1006 //
1007 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1008 // section. This address has enough space for an unconditional branch
1009 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1010 // initialized, and the address for the actual c2i_entry is known, we emit a
1011 // branch instruction here to branch to the actual c2i_entry.
1012 //
1013 // The effect of the extra branch on the i2i and c2i entries is negligible.
1014 //
1015 // The reason for putting _adapter_trampoline in RO is many shared Methods
1016 // share the same AdapterHandlerEntry, so we can save space in the RW section
1017 // by having the extra indirection.
1018 
1019 
1020 [Method A: RW]
1021   _constMethod ----> [ConstMethod: RO]
1022                        _adapter_trampoline -----------+
1023                                                       |
1024   _i2i_entry              (same value as method B)    |
1025   _from_interpreted_entry (same value as method B)    |
1026   _from_compiled_entry    (same value as method B)    |
1027                                                       |
1028                                                       |
1029 [Method B: RW]                               +--------+
1030   _constMethod ----> [ConstMethod: RO]       |
1031                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1032                                                                                  |
1033                                                  +-------------------------------+
1034                                                  |
1035                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1036                                                               _fingerprint
1037                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1038  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1039  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1040          |                |                                                             |                 |
1041          |                |  (_cds_entry_table: CODE)                                   |                 |
1042          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1043          |                |                               (allocated at run time)       |                 |
1044          |                |  ...                           [asm code ...]               |                 |
1045          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1046          |                                                                              |                 |
1047          |                                                                              |                 |
1048          +-[compiled]-------------------------------------------------------------------+                 |
1049                                                                                                           |
1050  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1051                                     [jmp c2i_entry] ------------------------------------------------------+
1052 
1053 ***/
1054 
1055 // Called when the method_holder is getting linked. Setup entrypoints so the method
1056 // is ready to be called from interpreter, compiler, and vtables.
1057 void Method::link_method(const methodHandle& h_method, TRAPS) {
1058   // If the code cache is full, we may reenter this function for the
1059   // leftover methods that weren't linked.
1060   if (is_shared()) {
1061     address entry = Interpreter::entry_for_cds_method(h_method);
1062     assert(entry != NULL && entry == _i2i_entry,
1063            "should be correctly set during dump time");
1064     if (adapter() != NULL) {
1065       return;
1066     }
1067     assert(entry == _from_interpreted_entry,
1068            "should be correctly set during dump time");
1069   } else if (_i2i_entry != NULL) {
1070     return;
1071   }
1072   assert( _code == NULL, "nothing compiled yet" );
1073 
1074   // Setup interpreter entrypoint
1075   assert(this == h_method(), "wrong h_method()" );
1076 
1077   if (!is_shared()) {
1078     assert(adapter() == NULL, "init'd to NULL");
1079     address entry = Interpreter::entry_for_method(h_method);
1080     assert(entry != NULL, "interpreter entry must be non-null");
1081     // Sets both _i2i_entry and _from_interpreted_entry
1082     set_interpreter_entry(entry);
1083   }
1084 
1085   // Don't overwrite already registered native entries.
1086   if (is_native() && !has_native_function()) {
1087     set_native_function(
1088       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1089       !native_bind_event_is_interesting);
1090   }
1091 
1092   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1093   // special handling of vtables.  An alternative is to make adapters more
1094   // lazily by calling make_adapter() from from_compiled_entry() for the
1095   // normal calls.  For vtable calls life gets more complicated.  When a
1096   // call-site goes mega-morphic we need adapters in all methods which can be
1097   // called from the vtable.  We need adapters on such methods that get loaded
1098   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1099   // problem we'll make these lazily later.
1100   (void) make_adapters(h_method, CHECK);
1101 
1102   // ONLY USE the h_method now as make_adapter may have blocked
1103 
1104 }
1105 
1106 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1107   // Adapters for compiled code are made eagerly here.  They are fairly
1108   // small (generally < 100 bytes) and quick to make (and cached and shared)
1109   // so making them eagerly shouldn't be too expensive.
1110   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh, CHECK_0);
1111   if (adapter == NULL ) {
1112     if (!is_init_completed()) {
1113       // Don't throw exceptions during VM initialization because java.lang.* classes
1114       // might not have been initialized, causing problems when constructing the
1115       // Java exception object.
1116       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1117     } else {
1118       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1119     }
1120   }
1121 
1122   if (mh->is_shared()) {
1123     assert(mh->adapter() == adapter, "must be");
1124     assert(mh->_from_compiled_entry != NULL, "must be");
1125     assert(mh->_from_compiled_value_entry != NULL, "must be");
1126   } else {
1127     mh->set_adapter_entry(adapter);
1128     mh->_from_compiled_entry = adapter->get_c2i_entry();
1129     mh->_from_compiled_value_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(this), "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   mh->_from_compiled_value_entry = mh->has_value_args() ? code->verified_value_entry_point() : code->verified_entry_point();
1199   OrderAccess::storestore();
1200   // Instantly compiled code can execute.
1201   if (!mh->is_method_handle_intrinsic())
1202     mh->_from_interpreted_entry = mh->get_i2c_entry();
1203 }
1204 
1205 
1206 bool Method::is_overridden_in(Klass* k) const {
1207   InstanceKlass* ik = InstanceKlass::cast(k);
1208 
1209   if (ik->is_interface()) return false;
1210 
1211   // If method is an interface, we skip it - except if it
1212   // is a miranda method
1213   if (method_holder()->is_interface()) {
1214     // Check that method is not a miranda method
1215     if (ik->lookup_method(name(), signature()) == NULL) {
1216       // No implementation exist - so miranda method
1217       return false;
1218     }
1219     return true;
1220   }
1221 
1222   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1223   if (!has_vtable_index()) {
1224     return false;
1225   } else {
1226     Method* vt_m = ik->method_at_vtable(vtable_index());
1227     return vt_m != this;
1228   }
1229 }
1230 
1231 
1232 // give advice about whether this Method* should be cached or not
1233 bool Method::should_not_be_cached() const {
1234   if (is_old()) {
1235     // This method has been redefined. It is either EMCP or obsolete
1236     // and we don't want to cache it because that would pin the method
1237     // down and prevent it from being collectible if and when it
1238     // finishes executing.
1239     return true;
1240   }
1241 
1242   // caching this method should be just fine
1243   return false;
1244 }
1245 
1246 
1247 /**
1248  *  Returns true if this is one of the specially treated methods for
1249  *  security related stack walks (like Reflection.getCallerClass).
1250  */
1251 bool Method::is_ignored_by_security_stack_walk() const {
1252   if (intrinsic_id() == vmIntrinsics::_invoke) {
1253     // This is Method.invoke() -- ignore it
1254     return true;
1255   }
1256   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1257     // This is an auxilary frame -- ignore it
1258     return true;
1259   }
1260   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1261     // This is an internal adapter frame for method handles -- ignore it
1262     return true;
1263   }
1264   return false;
1265 }
1266 
1267 
1268 // Constant pool structure for invoke methods:
1269 enum {
1270   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1271   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1272   _imcp_limit
1273 };
1274 
1275 // Test if this method is an MH adapter frame generated by Java code.
1276 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1277 bool Method::is_compiled_lambda_form() const {
1278   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1279 }
1280 
1281 // Test if this method is an internal MH primitive method.
1282 bool Method::is_method_handle_intrinsic() const {
1283   vmIntrinsics::ID iid = intrinsic_id();
1284   return (MethodHandles::is_signature_polymorphic(iid) &&
1285           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1286 }
1287 
1288 bool Method::has_member_arg() const {
1289   vmIntrinsics::ID iid = intrinsic_id();
1290   return (MethodHandles::is_signature_polymorphic(iid) &&
1291           MethodHandles::has_member_arg(iid));
1292 }
1293 
1294 // Make an instance of a signature-polymorphic internal MH primitive.
1295 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1296                                                          Symbol* signature,
1297                                                          TRAPS) {
1298   ResourceMark rm;
1299   methodHandle empty;
1300 
1301   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1302   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1303   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1304   if (TraceMethodHandles) {
1305     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1306   }
1307 
1308   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1309   name->increment_refcount();
1310   signature->increment_refcount();
1311 
1312   int cp_length = _imcp_limit;
1313   ClassLoaderData* loader_data = holder->class_loader_data();
1314   constantPoolHandle cp;
1315   {
1316     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1317     cp = constantPoolHandle(THREAD, cp_oop);
1318   }
1319   cp->set_pool_holder(holder);
1320   cp->symbol_at_put(_imcp_invoke_name,       name);
1321   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1322   cp->set_has_preresolution();
1323 
1324   // decide on access bits:  public or not?
1325   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1326   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1327   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1328   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1329 
1330   methodHandle m;
1331   {
1332     InlineTableSizes sizes;
1333     Method* m_oop = Method::allocate(loader_data, 0,
1334                                      accessFlags_from(flags_bits), &sizes,
1335                                      ConstMethod::NORMAL, CHECK_(empty));
1336     m = methodHandle(THREAD, m_oop);
1337   }
1338   m->set_constants(cp());
1339   m->set_name_index(_imcp_invoke_name);
1340   m->set_signature_index(_imcp_invoke_signature);
1341   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1342   assert(m->signature() == signature, "");
1343   ResultTypeFinder rtf(signature);
1344   m->constMethod()->set_result_type(rtf.type());
1345   m->compute_size_of_parameters(THREAD);
1346   m->init_intrinsic_id();
1347   assert(m->is_method_handle_intrinsic(), "");
1348 #ifdef ASSERT
1349   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1350   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1351   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1352 #endif //ASSERT
1353 
1354   // Finally, set up its entry points.
1355   assert(m->can_be_statically_bound(), "");
1356   m->set_vtable_index(Method::nonvirtual_vtable_index);
1357   m->link_method(m, CHECK_(empty));
1358 
1359   if (TraceMethodHandles && (Verbose || WizardMode)) {
1360     ttyLocker ttyl;
1361     m->print_on(tty);
1362   }
1363 
1364   return m;
1365 }
1366 
1367 Klass* Method::check_non_bcp_klass(Klass* klass) {
1368   if (klass != NULL && klass->class_loader() != NULL) {
1369     if (klass->is_objArray_klass())
1370       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1371     return klass;
1372   }
1373   return NULL;
1374 }
1375 
1376 
1377 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1378                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1379   // Code below does not work for native methods - they should never get rewritten anyway
1380   assert(!m->is_native(), "cannot rewrite native methods");
1381   // Allocate new Method*
1382   AccessFlags flags = m->access_flags();
1383 
1384   ConstMethod* cm = m->constMethod();
1385   int checked_exceptions_len = cm->checked_exceptions_length();
1386   int localvariable_len = cm->localvariable_table_length();
1387   int exception_table_len = cm->exception_table_length();
1388   int method_parameters_len = cm->method_parameters_length();
1389   int method_annotations_len = cm->method_annotations_length();
1390   int parameter_annotations_len = cm->parameter_annotations_length();
1391   int type_annotations_len = cm->type_annotations_length();
1392   int default_annotations_len = cm->default_annotations_length();
1393 
1394   InlineTableSizes sizes(
1395       localvariable_len,
1396       new_compressed_linenumber_size,
1397       exception_table_len,
1398       checked_exceptions_len,
1399       method_parameters_len,
1400       cm->generic_signature_index(),
1401       method_annotations_len,
1402       parameter_annotations_len,
1403       type_annotations_len,
1404       default_annotations_len,
1405       0);
1406 
1407   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1408   Method* newm_oop = Method::allocate(loader_data,
1409                                       new_code_length,
1410                                       flags,
1411                                       &sizes,
1412                                       m->method_type(),
1413                                       CHECK_(methodHandle()));
1414   methodHandle newm (THREAD, newm_oop);
1415 
1416   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1417   ConstMethod* newcm = newm->constMethod();
1418   int new_const_method_size = newm->constMethod()->size();
1419 
1420   // This works because the source and target are both Methods. Some compilers
1421   // (e.g., clang) complain that the target vtable pointer will be stomped,
1422   // so cast away newm()'s and m()'s Methodness.
1423   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1424 
1425   // Create shallow copy of ConstMethod.
1426   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1427 
1428   // Reset correct method/const method, method size, and parameter info
1429   newm->set_constMethod(newcm);
1430   newm->constMethod()->set_code_size(new_code_length);
1431   newm->constMethod()->set_constMethod_size(new_const_method_size);
1432   assert(newm->code_size() == new_code_length, "check");
1433   assert(newm->method_parameters_length() == method_parameters_len, "check");
1434   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1435   assert(newm->exception_table_length() == exception_table_len, "check");
1436   assert(newm->localvariable_table_length() == localvariable_len, "check");
1437   // Copy new byte codes
1438   memcpy(newm->code_base(), new_code, new_code_length);
1439   // Copy line number table
1440   if (new_compressed_linenumber_size > 0) {
1441     memcpy(newm->compressed_linenumber_table(),
1442            new_compressed_linenumber_table,
1443            new_compressed_linenumber_size);
1444   }
1445   // Copy method_parameters
1446   if (method_parameters_len > 0) {
1447     memcpy(newm->method_parameters_start(),
1448            m->method_parameters_start(),
1449            method_parameters_len * sizeof(MethodParametersElement));
1450   }
1451   // Copy checked_exceptions
1452   if (checked_exceptions_len > 0) {
1453     memcpy(newm->checked_exceptions_start(),
1454            m->checked_exceptions_start(),
1455            checked_exceptions_len * sizeof(CheckedExceptionElement));
1456   }
1457   // Copy exception table
1458   if (exception_table_len > 0) {
1459     memcpy(newm->exception_table_start(),
1460            m->exception_table_start(),
1461            exception_table_len * sizeof(ExceptionTableElement));
1462   }
1463   // Copy local variable number table
1464   if (localvariable_len > 0) {
1465     memcpy(newm->localvariable_table_start(),
1466            m->localvariable_table_start(),
1467            localvariable_len * sizeof(LocalVariableTableElement));
1468   }
1469   // Copy stackmap table
1470   if (m->has_stackmap_table()) {
1471     int code_attribute_length = m->stackmap_data()->length();
1472     Array<u1>* stackmap_data =
1473       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1474     memcpy((void*)stackmap_data->adr_at(0),
1475            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1476     newm->set_stackmap_data(stackmap_data);
1477   }
1478 
1479   // copy annotations over to new method
1480   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1481   return newm;
1482 }
1483 
1484 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1485   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1486   // because we are not loading from core libraries
1487   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1488   // which does not use the class default class loader so we check for its loader here
1489   const InstanceKlass* ik = InstanceKlass::cast(holder);
1490   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1491     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1492   }
1493 
1494   // see if the klass name is well-known:
1495   Symbol* klass_name = ik->name();
1496   return vmSymbols::find_sid(klass_name);
1497 }
1498 
1499 void Method::init_intrinsic_id() {
1500   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1501   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1502   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1503   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1504 
1505   // the klass name is well-known:
1506   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1507   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1508 
1509   // ditto for method and signature:
1510   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1511   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1512       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1513       && name_id == vmSymbols::NO_SID) {
1514     return;
1515   }
1516   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1517   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1518       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1519       && sig_id == vmSymbols::NO_SID) {
1520     return;
1521   }
1522   jshort flags = access_flags().as_short();
1523 
1524   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1525   if (id != vmIntrinsics::_none) {
1526     set_intrinsic_id(id);
1527     if (id == vmIntrinsics::_Class_cast) {
1528       // Even if the intrinsic is rejected, we want to inline this simple method.
1529       set_force_inline(true);
1530     }
1531     return;
1532   }
1533 
1534   // A few slightly irregular cases:
1535   switch (klass_id) {
1536   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1537     // Second chance: check in regular Math.
1538     switch (name_id) {
1539     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1540     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1541     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1542       // pretend it is the corresponding method in the non-strict class:
1543       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1544       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1545       break;
1546     default:
1547       break;
1548     }
1549     break;
1550 
1551   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1552   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1553   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1554     if (!is_native())  break;
1555     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1556     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1557       id = vmIntrinsics::_none;
1558     break;
1559 
1560   default:
1561     break;
1562   }
1563 
1564   if (id != vmIntrinsics::_none) {
1565     // Set up its iid.  It is an alias method.
1566     set_intrinsic_id(id);
1567     return;
1568   }
1569 }
1570 
1571 // These two methods are static since a GC may move the Method
1572 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1573   if (!THREAD->can_call_java()) {
1574     // There is nothing useful this routine can do from within the Compile thread.
1575     // Hopefully, the signature contains only well-known classes.
1576     // We could scan for this and return true/false, but the caller won't care.
1577     return false;
1578   }
1579   bool sig_is_loaded = true;
1580   Handle class_loader(THREAD, m->method_holder()->class_loader());
1581   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1582   ResourceMark rm(THREAD);
1583   Symbol*  signature = m->signature();
1584   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1585     if (ss.is_object()) {
1586       Symbol* sym = ss.as_symbol(CHECK_(false));
1587       Symbol*  name  = sym;
1588       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1589                                              protection_domain, THREAD);
1590       // We are loading classes eagerly. If a ClassNotFoundException or
1591       // a LinkageError was generated, be sure to ignore it.
1592       if (HAS_PENDING_EXCEPTION) {
1593         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1594             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1595           CLEAR_PENDING_EXCEPTION;
1596         } else {
1597           return false;
1598         }
1599       }
1600       if( klass == NULL) { sig_is_loaded = false; }
1601     }
1602   }
1603   return sig_is_loaded;
1604 }
1605 
1606 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1607   Handle class_loader(THREAD, m->method_holder()->class_loader());
1608   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1609   ResourceMark rm(THREAD);
1610   Symbol*  signature = m->signature();
1611   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1612     if (ss.type() == T_OBJECT) {
1613       Symbol* name = ss.as_symbol_or_null();
1614       if (name == NULL) return true;
1615       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1616       if (klass == NULL) return true;
1617     }
1618   }
1619   return false;
1620 }
1621 
1622 // Exposed so field engineers can debug VM
1623 void Method::print_short_name(outputStream* st) {
1624   ResourceMark rm;
1625 #ifdef PRODUCT
1626   st->print(" %s::", method_holder()->external_name());
1627 #else
1628   st->print(" %s::", method_holder()->internal_name());
1629 #endif
1630   name()->print_symbol_on(st);
1631   if (WizardMode) signature()->print_symbol_on(st);
1632   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1633     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1634 }
1635 
1636 // Comparer for sorting an object array containing
1637 // Method*s.
1638 static int method_comparator(Method* a, Method* b) {
1639   return a->name()->fast_compare(b->name());
1640 }
1641 
1642 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1643 // default_methods also uses this without the ordering for fast find_method
1644 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1645   int length = methods->length();
1646   if (length > 1) {
1647     {
1648       NoSafepointVerifier nsv;
1649       QuickSort::sort(methods->data(), length, method_comparator, idempotent);
1650     }
1651     // Reset method ordering
1652     if (set_idnums) {
1653       for (int i = 0; i < length; i++) {
1654         Method* m = methods->at(i);
1655         m->set_method_idnum(i);
1656         m->set_orig_method_idnum(i);
1657       }
1658     }
1659   }
1660 }
1661 
1662 //-----------------------------------------------------------------------------------
1663 // Non-product code unless JVM/TI needs it
1664 
1665 #if !defined(PRODUCT) || INCLUDE_JVMTI
1666 class SignatureTypePrinter : public SignatureTypeNames {
1667  private:
1668   outputStream* _st;
1669   bool _use_separator;
1670 
1671   void type_name(const char* name) {
1672     if (_use_separator) _st->print(", ");
1673     _st->print("%s", name);
1674     _use_separator = true;
1675   }
1676 
1677  public:
1678   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1679     _st = st;
1680     _use_separator = false;
1681   }
1682 
1683   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1684   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1685 };
1686 
1687 
1688 void Method::print_name(outputStream* st) {
1689   Thread *thread = Thread::current();
1690   ResourceMark rm(thread);
1691   st->print("%s ", is_static() ? "static" : "virtual");
1692   if (WizardMode) {
1693     st->print("%s.", method_holder()->internal_name());
1694     name()->print_symbol_on(st);
1695     signature()->print_symbol_on(st);
1696   } else {
1697     SignatureTypePrinter sig(signature(), st);
1698     sig.print_returntype();
1699     st->print(" %s.", method_holder()->internal_name());
1700     name()->print_symbol_on(st);
1701     st->print("(");
1702     sig.print_parameters();
1703     st->print(")");
1704   }
1705 }
1706 #endif // !PRODUCT || INCLUDE_JVMTI
1707 
1708 
1709 void Method::print_codes_on(outputStream* st) const {
1710   print_codes_on(0, code_size(), st);
1711 }
1712 
1713 void Method::print_codes_on(int from, int to, outputStream* st) const {
1714   Thread *thread = Thread::current();
1715   ResourceMark rm(thread);
1716   methodHandle mh (thread, (Method*)this);
1717   BytecodeStream s(mh);
1718   s.set_interval(from, to);
1719   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1720   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1721 }
1722 
1723 
1724 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1725 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1726 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1727 // as end-of-stream terminator.
1728 
1729 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1730   // bci and line number does not compress into single byte.
1731   // Write out escape character and use regular compression for bci and line number.
1732   write_byte((jubyte)0xFF);
1733   write_signed_int(bci_delta);
1734   write_signed_int(line_delta);
1735 }
1736 
1737 // See comment in method.hpp which explains why this exists.
1738 #if defined(_M_AMD64) && _MSC_VER >= 1400
1739 #pragma optimize("", off)
1740 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1741   write_pair_inline(bci, line);
1742 }
1743 #pragma optimize("", on)
1744 #endif
1745 
1746 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1747   _bci = 0;
1748   _line = 0;
1749 };
1750 
1751 
1752 bool CompressedLineNumberReadStream::read_pair() {
1753   jubyte next = read_byte();
1754   // Check for terminator
1755   if (next == 0) return false;
1756   if (next == 0xFF) {
1757     // Escape character, regular compression used
1758     _bci  += read_signed_int();
1759     _line += read_signed_int();
1760   } else {
1761     // Single byte compression used
1762     _bci  += next >> 3;
1763     _line += next & 0x7;
1764   }
1765   return true;
1766 }
1767 
1768 #if INCLUDE_JVMTI
1769 
1770 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1771   BreakpointInfo* bp = method_holder()->breakpoints();
1772   for (; bp != NULL; bp = bp->next()) {
1773     if (bp->match(this, bci)) {
1774       return bp->orig_bytecode();
1775     }
1776   }
1777   {
1778     ResourceMark rm;
1779     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1780   }
1781   return Bytecodes::_shouldnotreachhere;
1782 }
1783 
1784 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1785   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1786   BreakpointInfo* bp = method_holder()->breakpoints();
1787   for (; bp != NULL; bp = bp->next()) {
1788     if (bp->match(this, bci)) {
1789       bp->set_orig_bytecode(code);
1790       // and continue, in case there is more than one
1791     }
1792   }
1793 }
1794 
1795 void Method::set_breakpoint(int bci) {
1796   InstanceKlass* ik = method_holder();
1797   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1798   bp->set_next(ik->breakpoints());
1799   ik->set_breakpoints(bp);
1800   // do this last:
1801   bp->set(this);
1802 }
1803 
1804 static void clear_matches(Method* m, int bci) {
1805   InstanceKlass* ik = m->method_holder();
1806   BreakpointInfo* prev_bp = NULL;
1807   BreakpointInfo* next_bp;
1808   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1809     next_bp = bp->next();
1810     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1811     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1812       // do this first:
1813       bp->clear(m);
1814       // unhook it
1815       if (prev_bp != NULL)
1816         prev_bp->set_next(next_bp);
1817       else
1818         ik->set_breakpoints(next_bp);
1819       delete bp;
1820       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1821       // at same location. So we have multiple matching (method_index and bci)
1822       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1823       // breakpoint for clear_breakpoint request and keep all other method versions
1824       // BreakpointInfo for future clear_breakpoint request.
1825       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1826       // which is being called when class is unloaded. We delete all the Breakpoint
1827       // information for all versions of method. We may not correctly restore the original
1828       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1829       // so these methods won't be used anymore.
1830       if (bci >= 0) {
1831         break;
1832       }
1833     } else {
1834       // This one is a keeper.
1835       prev_bp = bp;
1836     }
1837   }
1838 }
1839 
1840 void Method::clear_breakpoint(int bci) {
1841   assert(bci >= 0, "");
1842   clear_matches(this, bci);
1843 }
1844 
1845 void Method::clear_all_breakpoints() {
1846   clear_matches(this, -1);
1847 }
1848 
1849 #endif // INCLUDE_JVMTI
1850 
1851 int Method::invocation_count() {
1852   MethodCounters *mcs = method_counters();
1853   if (TieredCompilation) {
1854     MethodData* const mdo = method_data();
1855     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1856         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1857       return InvocationCounter::count_limit;
1858     } else {
1859       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1860              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1861     }
1862   } else {
1863     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1864   }
1865 }
1866 
1867 int Method::backedge_count() {
1868   MethodCounters *mcs = method_counters();
1869   if (TieredCompilation) {
1870     MethodData* const mdo = method_data();
1871     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1872         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1873       return InvocationCounter::count_limit;
1874     } else {
1875       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1876              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1877     }
1878   } else {
1879     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1880   }
1881 }
1882 
1883 void Method::initialize_max_vt_buffer() {
1884   long long max_entries = constMethod()->max_locals() + constMethod()->max_stack();
1885   max_entries *= 2; // Add margin for loops
1886   long long max_size = max_entries * (BigValueTypeThreshold + 8); // 8 -> header size
1887   int max_chunks = (int)(max_size / VTBufferChunk::max_alloc_size()) + 1;
1888   set_max_vt_buffer(MAX2(MinimumVTBufferChunkPerFrame, max_chunks));
1889 }
1890 
1891 int Method::highest_comp_level() const {
1892   const MethodCounters* mcs = method_counters();
1893   if (mcs != NULL) {
1894     return mcs->highest_comp_level();
1895   } else {
1896     return CompLevel_none;
1897   }
1898 }
1899 
1900 int Method::highest_osr_comp_level() const {
1901   const MethodCounters* mcs = method_counters();
1902   if (mcs != NULL) {
1903     return mcs->highest_osr_comp_level();
1904   } else {
1905     return CompLevel_none;
1906   }
1907 }
1908 
1909 void Method::set_highest_comp_level(int level) {
1910   MethodCounters* mcs = method_counters();
1911   if (mcs != NULL) {
1912     mcs->set_highest_comp_level(level);
1913   }
1914 }
1915 
1916 void Method::set_highest_osr_comp_level(int level) {
1917   MethodCounters* mcs = method_counters();
1918   if (mcs != NULL) {
1919     mcs->set_highest_osr_comp_level(level);
1920   }
1921 }
1922 
1923 #if INCLUDE_JVMTI
1924 
1925 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1926   _bci = bci;
1927   _name_index = m->name_index();
1928   _signature_index = m->signature_index();
1929   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1930   if (_orig_bytecode == Bytecodes::_breakpoint)
1931     _orig_bytecode = m->orig_bytecode_at(_bci);
1932   _next = NULL;
1933 }
1934 
1935 void BreakpointInfo::set(Method* method) {
1936 #ifdef ASSERT
1937   {
1938     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1939     if (code == Bytecodes::_breakpoint)
1940       code = method->orig_bytecode_at(_bci);
1941     assert(orig_bytecode() == code, "original bytecode must be the same");
1942   }
1943 #endif
1944   Thread *thread = Thread::current();
1945   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1946   method->incr_number_of_breakpoints(thread);
1947   SystemDictionary::notice_modification();
1948   {
1949     // Deoptimize all dependents on this method
1950     HandleMark hm(thread);
1951     methodHandle mh(thread, method);
1952     CodeCache::flush_dependents_on_method(mh);
1953   }
1954 }
1955 
1956 void BreakpointInfo::clear(Method* method) {
1957   *method->bcp_from(_bci) = orig_bytecode();
1958   assert(method->number_of_breakpoints() > 0, "must not go negative");
1959   method->decr_number_of_breakpoints(Thread::current());
1960 }
1961 
1962 #endif // INCLUDE_JVMTI
1963 
1964 // jmethodID handling
1965 
1966 // This is a block allocating object, sort of like JNIHandleBlock, only a
1967 // lot simpler.
1968 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1969 // never get rid of it.
1970 
1971 static const int min_block_size = 8;
1972 
1973 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1974   friend class JNIMethodBlock;
1975   Method**        _methods;
1976   int             _number_of_methods;
1977   int             _top;
1978   JNIMethodBlockNode* _next;
1979 
1980  public:
1981 
1982   JNIMethodBlockNode(int num_methods = min_block_size);
1983 
1984   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1985 
1986   void ensure_methods(int num_addl_methods) {
1987     if (_top < _number_of_methods) {
1988       num_addl_methods -= _number_of_methods - _top;
1989       if (num_addl_methods <= 0) {
1990         return;
1991       }
1992     }
1993     if (_next == NULL) {
1994       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1995     } else {
1996       _next->ensure_methods(num_addl_methods);
1997     }
1998   }
1999 };
2000 
2001 class JNIMethodBlock : public CHeapObj<mtClass> {
2002   JNIMethodBlockNode _head;
2003   JNIMethodBlockNode *_last_free;
2004  public:
2005   static Method* const _free_method;
2006 
2007   JNIMethodBlock(int initial_capacity = min_block_size)
2008       : _head(initial_capacity), _last_free(&_head) {}
2009 
2010   void ensure_methods(int num_addl_methods) {
2011     _last_free->ensure_methods(num_addl_methods);
2012   }
2013 
2014   Method** add_method(Method* m) {
2015     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2016       if (b->_top < b->_number_of_methods) {
2017         // top points to the next free entry.
2018         int i = b->_top;
2019         b->_methods[i] = m;
2020         b->_top++;
2021         _last_free = b;
2022         return &(b->_methods[i]);
2023       } else if (b->_top == b->_number_of_methods) {
2024         // if the next free entry ran off the block see if there's a free entry
2025         for (int i = 0; i < b->_number_of_methods; i++) {
2026           if (b->_methods[i] == _free_method) {
2027             b->_methods[i] = m;
2028             _last_free = b;
2029             return &(b->_methods[i]);
2030           }
2031         }
2032         // Only check each block once for frees.  They're very unlikely.
2033         // Increment top past the end of the block.
2034         b->_top++;
2035       }
2036       // need to allocate a next block.
2037       if (b->_next == NULL) {
2038         b->_next = _last_free = new JNIMethodBlockNode();
2039       }
2040     }
2041     guarantee(false, "Should always allocate a free block");
2042     return NULL;
2043   }
2044 
2045   bool contains(Method** m) {
2046     if (m == NULL) return false;
2047     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2048       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2049         // This is a bit of extra checking, for two reasons.  One is
2050         // that contains() deals with pointers that are passed in by
2051         // JNI code, so making sure that the pointer is aligned
2052         // correctly is valuable.  The other is that <= and > are
2053         // technically not defined on pointers, so the if guard can
2054         // pass spuriously; no modern compiler is likely to make that
2055         // a problem, though (and if one did, the guard could also
2056         // fail spuriously, which would be bad).
2057         ptrdiff_t idx = m - b->_methods;
2058         if (b->_methods + idx == m) {
2059           return true;
2060         }
2061       }
2062     }
2063     return false;  // not found
2064   }
2065 
2066   // Doesn't really destroy it, just marks it as free so it can be reused.
2067   void destroy_method(Method** m) {
2068 #ifdef ASSERT
2069     assert(contains(m), "should be a methodID");
2070 #endif // ASSERT
2071     *m = _free_method;
2072   }
2073 
2074   // During class unloading the methods are cleared, which is different
2075   // than freed.
2076   void clear_all_methods() {
2077     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2078       for (int i = 0; i< b->_number_of_methods; i++) {
2079         b->_methods[i] = NULL;
2080       }
2081     }
2082   }
2083 #ifndef PRODUCT
2084   int count_methods() {
2085     // count all allocated methods
2086     int count = 0;
2087     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2088       for (int i = 0; i< b->_number_of_methods; i++) {
2089         if (b->_methods[i] != _free_method) count++;
2090       }
2091     }
2092     return count;
2093   }
2094 #endif // PRODUCT
2095 };
2096 
2097 // Something that can't be mistaken for an address or a markOop
2098 Method* const JNIMethodBlock::_free_method = (Method*)55;
2099 
2100 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2101   _number_of_methods = MAX2(num_methods, min_block_size);
2102   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2103   for (int i = 0; i < _number_of_methods; i++) {
2104     _methods[i] = JNIMethodBlock::_free_method;
2105   }
2106 }
2107 
2108 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2109   ClassLoaderData* cld = loader_data;
2110   if (!SafepointSynchronize::is_at_safepoint()) {
2111     // Have to add jmethod_ids() to class loader data thread-safely.
2112     // Also have to add the method to the list safely, which the cld lock
2113     // protects as well.
2114     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2115     if (cld->jmethod_ids() == NULL) {
2116       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2117     } else {
2118       cld->jmethod_ids()->ensure_methods(capacity);
2119     }
2120   } else {
2121     // At safepoint, we are single threaded and can set this.
2122     if (cld->jmethod_ids() == NULL) {
2123       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2124     } else {
2125       cld->jmethod_ids()->ensure_methods(capacity);
2126     }
2127   }
2128 }
2129 
2130 // Add a method id to the jmethod_ids
2131 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2132   ClassLoaderData* cld = loader_data;
2133 
2134   if (!SafepointSynchronize::is_at_safepoint()) {
2135     // Have to add jmethod_ids() to class loader data thread-safely.
2136     // Also have to add the method to the list safely, which the cld lock
2137     // protects as well.
2138     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2139     if (cld->jmethod_ids() == NULL) {
2140       cld->set_jmethod_ids(new JNIMethodBlock());
2141     }
2142     // jmethodID is a pointer to Method*
2143     return (jmethodID)cld->jmethod_ids()->add_method(m);
2144   } else {
2145     // At safepoint, we are single threaded and can set this.
2146     if (cld->jmethod_ids() == NULL) {
2147       cld->set_jmethod_ids(new JNIMethodBlock());
2148     }
2149     // jmethodID is a pointer to Method*
2150     return (jmethodID)cld->jmethod_ids()->add_method(m);
2151   }
2152 }
2153 
2154 // Mark a jmethodID as free.  This is called when there is a data race in
2155 // InstanceKlass while creating the jmethodID cache.
2156 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2157   ClassLoaderData* cld = loader_data;
2158   Method** ptr = (Method**)m;
2159   assert(cld->jmethod_ids() != NULL, "should have method handles");
2160   cld->jmethod_ids()->destroy_method(ptr);
2161 }
2162 
2163 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2164   // Can't assert the method_holder is the same because the new method has the
2165   // scratch method holder.
2166   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2167            == new_method->method_holder()->class_loader(),
2168          "changing to a different class loader");
2169   // Just change the method in place, jmethodID pointer doesn't change.
2170   *((Method**)jmid) = new_method;
2171 }
2172 
2173 bool Method::is_method_id(jmethodID mid) {
2174   Method* m = resolve_jmethod_id(mid);
2175   assert(m != NULL, "should be called with non-null method");
2176   InstanceKlass* ik = m->method_holder();
2177   ClassLoaderData* cld = ik->class_loader_data();
2178   if (cld->jmethod_ids() == NULL) return false;
2179   return (cld->jmethod_ids()->contains((Method**)mid));
2180 }
2181 
2182 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2183   if (mid == NULL) return NULL;
2184   Method* o = resolve_jmethod_id(mid);
2185   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2186     return NULL;
2187   }
2188   return o;
2189 };
2190 
2191 void Method::set_on_stack(const bool value) {
2192   // Set both the method itself and its constant pool.  The constant pool
2193   // on stack means some method referring to it is also on the stack.
2194   constants()->set_on_stack(value);
2195 
2196   bool already_set = on_stack();
2197   _access_flags.set_on_stack(value);
2198   if (value && !already_set) {
2199     MetadataOnStackMark::record(this);
2200   }
2201 }
2202 
2203 // Called when the class loader is unloaded to make all methods weak.
2204 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2205   loader_data->jmethod_ids()->clear_all_methods();
2206 }
2207 
2208 bool Method::has_method_vptr(const void* ptr) {
2209   Method m;
2210   // This assumes that the vtbl pointer is the first word of a C++ object.
2211   return dereference_vptr(&m) == dereference_vptr(ptr);
2212 }
2213 
2214 // Check that this pointer is valid by checking that the vtbl pointer matches
2215 bool Method::is_valid_method(const Method* m) {
2216   if (m == NULL) {
2217     return false;
2218   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2219     // Quick sanity check on pointer.
2220     return false;
2221   } else if (m->is_shared()) {
2222     return MetaspaceShared::is_valid_shared_method(m);
2223   } else if (Metaspace::contains_non_shared(m)) {
2224     return has_method_vptr((const void*)m);
2225   } else {
2226     return false;
2227   }
2228 }
2229 
2230 #ifndef PRODUCT
2231 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2232   out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2233 }
2234 #endif // PRODUCT
2235 
2236 
2237 // Printing
2238 
2239 #ifndef PRODUCT
2240 
2241 void Method::print_on(outputStream* st) const {
2242   ResourceMark rm;
2243   assert(is_method(), "must be method");
2244   st->print_cr("%s", internal_name());
2245   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2246   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2247   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2248   constants()->print_value_on(st); st->cr();
2249   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2250   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2251   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2252   st->print_cr(" - max stack:         %d",   max_stack());
2253   st->print_cr(" - max locals:        %d",   max_locals());
2254   st->print_cr(" - size of params:    %d",   size_of_parameters());
2255   st->print_cr(" - method size:       %d",   method_size());
2256   if (intrinsic_id() != vmIntrinsics::_none)
2257     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2258   if (highest_comp_level() != CompLevel_none)
2259     st->print_cr(" - highest level:     %d", highest_comp_level());
2260   st->print_cr(" - vtable index:      %d",   _vtable_index);
2261   if (valid_itable_index())
2262     st->print_cr(" - itable index:      %d",   itable_index());
2263   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2264   st->print(   " - adapters:          ");
2265   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2266   if (a == NULL)
2267     st->print_cr(INTPTR_FORMAT, p2i(a));
2268   else
2269     a->print_adapter_on(st);
2270   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2271   st->print_cr(" - code size:         %d",   code_size());
2272   if (code_size() != 0) {
2273     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2274     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2275   }
2276   if (method_data() != NULL) {
2277     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2278   }
2279   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2280   if (checked_exceptions_length() > 0) {
2281     CheckedExceptionElement* table = checked_exceptions_start();
2282     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2283     if (Verbose) {
2284       for (int i = 0; i < checked_exceptions_length(); i++) {
2285         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2286       }
2287     }
2288   }
2289   if (has_linenumber_table()) {
2290     u_char* table = compressed_linenumber_table();
2291     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2292     if (Verbose) {
2293       CompressedLineNumberReadStream stream(table);
2294       while (stream.read_pair()) {
2295         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2296       }
2297     }
2298   }
2299   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2300   if (localvariable_table_length() > 0) {
2301     LocalVariableTableElement* table = localvariable_table_start();
2302     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2303     if (Verbose) {
2304       for (int i = 0; i < localvariable_table_length(); i++) {
2305         int bci = table[i].start_bci;
2306         int len = table[i].length;
2307         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2308         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2309         int slot = table[i].slot;
2310         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2311       }
2312     }
2313   }
2314   if (code() != NULL) {
2315     st->print   (" - compiled code: ");
2316     code()->print_value_on(st);
2317   }
2318   if (is_native()) {
2319     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2320     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2321   }
2322 }
2323 
2324 void Method::print_linkage_flags(outputStream* st) {
2325   access_flags().print_on(st);
2326   if (is_default_method()) {
2327     st->print("default ");
2328   }
2329   if (is_overpass()) {
2330     st->print("overpass ");
2331   }
2332 }
2333 #endif //PRODUCT
2334 
2335 void Method::print_value_on(outputStream* st) const {
2336   assert(is_method(), "must be method");
2337   st->print("%s", internal_name());
2338   print_address_on(st);
2339   st->print(" ");
2340   if (WizardMode) access_flags().print_on(st);
2341   name()->print_value_on(st);
2342   st->print(" ");
2343   signature()->print_value_on(st);
2344   st->print(" in ");
2345   method_holder()->print_value_on(st);
2346   if (WizardMode) st->print("#%d", _vtable_index);
2347   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2348   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2349 }
2350 
2351 #if INCLUDE_SERVICES
2352 // Size Statistics
2353 void Method::collect_statistics(KlassSizeStats *sz) const {
2354   int mysize = sz->count(this);
2355   sz->_method_bytes += mysize;
2356   sz->_method_all_bytes += mysize;
2357   sz->_rw_bytes += mysize;
2358 
2359   if (constMethod()) {
2360     constMethod()->collect_statistics(sz);
2361   }
2362   if (method_data()) {
2363     method_data()->collect_statistics(sz);
2364   }
2365 }
2366 #endif // INCLUDE_SERVICES
2367 
2368 // LogTouchedMethods and PrintTouchedMethods
2369 
2370 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2371 // the Method may be garbage collected. Let's roll our own hash table.
2372 class TouchedMethodRecord : CHeapObj<mtTracing> {
2373 public:
2374   // It's OK to store Symbols here because they will NOT be GC'ed if
2375   // LogTouchedMethods is enabled.
2376   TouchedMethodRecord* _next;
2377   Symbol* _class_name;
2378   Symbol* _method_name;
2379   Symbol* _method_signature;
2380 };
2381 
2382 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2383 static TouchedMethodRecord** _touched_method_table = NULL;
2384 
2385 void Method::log_touched(TRAPS) {
2386 
2387   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2388   Symbol* my_class = klass_name();
2389   Symbol* my_name  = name();
2390   Symbol* my_sig   = signature();
2391 
2392   unsigned int hash = my_class->identity_hash() +
2393                       my_name->identity_hash() +
2394                       my_sig->identity_hash();
2395   juint index = juint(hash) % table_size;
2396 
2397   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2398   if (_touched_method_table == NULL) {
2399     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2400                                               mtTracing, CURRENT_PC);
2401     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2402   }
2403 
2404   TouchedMethodRecord* ptr = _touched_method_table[index];
2405   while (ptr) {
2406     if (ptr->_class_name       == my_class &&
2407         ptr->_method_name      == my_name &&
2408         ptr->_method_signature == my_sig) {
2409       return;
2410     }
2411     if (ptr->_next == NULL) break;
2412     ptr = ptr->_next;
2413   }
2414   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2415   my_class->increment_refcount();
2416   my_name->increment_refcount();
2417   my_sig->increment_refcount();
2418   nptr->_class_name         = my_class;
2419   nptr->_method_name        = my_name;
2420   nptr->_method_signature   = my_sig;
2421   nptr->_next               = NULL;
2422 
2423   if (ptr == NULL) {
2424     // first
2425     _touched_method_table[index] = nptr;
2426   } else {
2427     ptr->_next = nptr;
2428   }
2429 }
2430 
2431 void Method::print_touched_methods(outputStream* out) {
2432   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2433   out->print_cr("# Method::print_touched_methods version 1");
2434   if (_touched_method_table) {
2435     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2436       TouchedMethodRecord* ptr = _touched_method_table[i];
2437       while(ptr) {
2438         ptr->_class_name->print_symbol_on(out);       out->print(".");
2439         ptr->_method_name->print_symbol_on(out);      out->print(":");
2440         ptr->_method_signature->print_symbol_on(out); out->cr();
2441         ptr = ptr->_next;
2442       }
2443     }
2444   }
2445 }
2446 
2447 // Verification
2448 
2449 void Method::verify_on(outputStream* st) {
2450   guarantee(is_method(), "object must be method");
2451   guarantee(constants()->is_constantPool(), "should be constant pool");
2452   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2453   MethodData* md = method_data();
2454   guarantee(md == NULL ||
2455       md->is_methodData(), "should be method data");
2456 }