1 /*
   2  * Copyright (c) 1997, 2019, 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/classLoaderDataGraph.hpp"
  27 #include "classfile/metadataOnStackMark.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "code/debugInfoRec.hpp"
  31 #include "gc/shared/collectedHeap.inline.hpp"
  32 #include "interpreter/bytecodeStream.hpp"
  33 #include "interpreter/bytecodeTracer.hpp"
  34 #include "interpreter/bytecodes.hpp"
  35 #include "interpreter/interpreter.hpp"
  36 #include "interpreter/oopMapCache.hpp"
  37 #include "memory/allocation.inline.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceClosure.hpp"
  41 #include "memory/metaspaceShared.hpp"
  42 #include "memory/oopFactory.hpp"
  43 #include "memory/resourceArea.hpp"
  44 #include "memory/universe.hpp"
  45 #include "oops/constMethod.hpp"
  46 #include "oops/constantPool.hpp"
  47 #include "oops/method.inline.hpp"
  48 #include "oops/methodData.hpp"
  49 #include "oops/objArrayKlass.hpp"
  50 #include "oops/objArrayOop.inline.hpp"
  51 #include "oops/oop.inline.hpp"
  52 #include "oops/symbol.hpp"
  53 #include "oops/valueKlass.hpp"
  54 #include "prims/jvmtiExport.hpp"
  55 #include "prims/methodHandles.hpp"
  56 #include "prims/nativeLookup.hpp"
  57 #include "runtime/arguments.hpp"
  58 #include "runtime/compilationPolicy.hpp"
  59 #include "runtime/frame.inline.hpp"
  60 #include "runtime/handles.inline.hpp"
  61 #include "runtime/init.hpp"
  62 #include "runtime/orderAccess.hpp"
  63 #include "runtime/relocator.hpp"
  64 #include "runtime/safepointVerifiers.hpp"
  65 #include "runtime/sharedRuntime.hpp"
  66 #include "runtime/signature.hpp"
  67 #include "utilities/align.hpp"
  68 #include "utilities/quickSort.hpp"
  69 #include "utilities/vmError.hpp"
  70 #include "utilities/xmlstream.hpp"
  71 
  72 // Implementation of Method
  73 
  74 Method* Method::allocate(ClassLoaderData* loader_data,
  75                          int byte_code_size,
  76                          AccessFlags access_flags,
  77                          InlineTableSizes* sizes,
  78                          ConstMethod::MethodType method_type,
  79                          TRAPS) {
  80   assert(!access_flags.is_native() || byte_code_size == 0,
  81          "native methods should not contain byte codes");
  82   ConstMethod* cm = ConstMethod::allocate(loader_data,
  83                                           byte_code_size,
  84                                           sizes,
  85                                           method_type,
  86                                           CHECK_NULL);
  87   int size = Method::size(access_flags.is_native());
  88   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  89 }
  90 
  91 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  92   NoSafepointVerifier no_safepoint;
  93   set_constMethod(xconst);
  94   set_access_flags(access_flags);
  95   set_intrinsic_id(vmIntrinsics::_none);
  96   set_force_inline(false);
  97   set_hidden(false);
  98   set_dont_inline(false);
  99   set_has_injected_profile(false);
 100   set_method_data(NULL);
 101   clear_method_counters();
 102   set_vtable_index(Method::garbage_vtable_index);
 103 
 104   // Fix and bury in Method*
 105   set_interpreter_entry(NULL); // sets i2i entry and from_int
 106   set_adapter_entry(NULL);
 107   Method::clear_code(); // from_c/from_i get set to c2i/i2i
 108 
 109   if (access_flags.is_native()) {
 110     clear_native_function();
 111     set_signature_handler(NULL);
 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 #if INCLUDE_JVMCI
 122   if (method_data()) {
 123     FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
 124   }
 125 #endif
 126   MetadataFactory::free_metadata(loader_data, method_data());
 127   set_method_data(NULL);
 128   MetadataFactory::free_metadata(loader_data, method_counters());
 129   clear_method_counters();
 130   // The nmethod will be gone when we get here.
 131   if (code() != NULL) _code = NULL;
 132 }
 133 
 134 address Method::get_i2c_entry() {
 135   assert(adapter() != NULL, "must have");
 136   return adapter()->get_i2c_entry();
 137 }
 138 
 139 address Method::get_c2i_entry() {
 140   assert(adapter() != NULL, "must have");
 141   return adapter()->get_c2i_entry();
 142 }
 143 
 144 address Method::get_c2i_value_entry() {
 145   assert(adapter() != NULL, "must have");
 146   return adapter()->get_c2i_value_entry();
 147 }
 148 
 149 address Method::get_c2i_unverified_entry() {
 150   assert(adapter() != NULL, "must have");
 151   return adapter()->get_c2i_unverified_entry();
 152 }
 153 
 154 address Method::get_c2i_unverified_value_entry() {
 155   assert(adapter() != NULL, "must have");
 156   return adapter()->get_c2i_unverified_value_entry();
 157 }
 158 
 159 char* Method::name_and_sig_as_C_string() const {
 160   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 161 }
 162 
 163 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 164   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 165 }
 166 
 167 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 168   const char* klass_name = klass->external_name();
 169   int klass_name_len  = (int)strlen(klass_name);
 170   int method_name_len = method_name->utf8_length();
 171   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 172   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 173   strcpy(dest, klass_name);
 174   dest[klass_name_len] = '.';
 175   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 176   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 177   dest[len] = 0;
 178   return dest;
 179 }
 180 
 181 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 182   Symbol* klass_name = klass->name();
 183   klass_name->as_klass_external_name(buf, size);
 184   int len = (int)strlen(buf);
 185 
 186   if (len < size - 1) {
 187     buf[len++] = '.';
 188 
 189     method_name->as_C_string(&(buf[len]), size - len);
 190     len = (int)strlen(buf);
 191 
 192     signature->as_C_string(&(buf[len]), size - len);
 193   }
 194 
 195   return buf;
 196 }
 197 
 198 const char* Method::external_name() const {
 199   return external_name(constants()->pool_holder(), name(), signature());
 200 }
 201 
 202 void Method::print_external_name(outputStream *os) const {
 203   print_external_name(os, constants()->pool_holder(), name(), signature());
 204 }
 205 
 206 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
 207   stringStream ss;
 208   print_external_name(&ss, klass, method_name, signature);
 209   return ss.as_string();
 210 }
 211 
 212 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
 213   signature->print_as_signature_external_return_type(os);
 214   os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
 215   signature->print_as_signature_external_parameters(os);
 216   os->print(")");
 217 }
 218 
 219 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 220   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 221   // access exception table
 222   ExceptionTable table(mh());
 223   int length = table.length();
 224   // iterate through all entries sequentially
 225   constantPoolHandle pool(THREAD, mh->constants());
 226   for (int i = 0; i < length; i ++) {
 227     //reacquire the table in case a GC happened
 228     ExceptionTable table(mh());
 229     int beg_bci = table.start_pc(i);
 230     int end_bci = table.end_pc(i);
 231     assert(beg_bci <= end_bci, "inconsistent exception table");
 232     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 233       // exception handler bci range covers throw_bci => investigate further
 234       int handler_bci = table.handler_pc(i);
 235       int klass_index = table.catch_type_index(i);
 236       if (klass_index == 0) {
 237         return handler_bci;
 238       } else if (ex_klass == NULL) {
 239         return handler_bci;
 240       } else {
 241         // we know the exception class => get the constraint class
 242         // this may require loading of the constraint class; if verification
 243         // fails or some other exception occurs, return handler_bci
 244         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 245         assert(k != NULL, "klass not loaded");
 246         if (ex_klass->is_subtype_of(k)) {
 247           return handler_bci;
 248         }
 249       }
 250     }
 251   }
 252 
 253   return -1;
 254 }
 255 
 256 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 257   methodHandle h_this(Thread::current(), this);
 258   // Only GC uses the OopMapCache during thread stack root scanning
 259   // any other uses generate an oopmap but do not save it in the cache.
 260   if (Universe::heap()->is_gc_active()) {
 261     method_holder()->mask_for(h_this, bci, mask);
 262   } else {
 263     OopMapCache::compute_one_oop_map(h_this, bci, mask);
 264   }
 265   return;
 266 }
 267 
 268 
 269 int Method::bci_from(address bcp) const {
 270   if (is_native() && bcp == 0) {
 271     return 0;
 272   }
 273 #ifdef ASSERT
 274   {
 275     ResourceMark rm;
 276     assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
 277            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 278            p2i(bcp), name_and_sig_as_C_string());
 279   }
 280 #endif
 281   return bcp - code_base();
 282 }
 283 
 284 
 285 int Method::validate_bci(int bci) const {
 286   return (bci == 0 || bci < code_size()) ? bci : -1;
 287 }
 288 
 289 // Return bci if it appears to be a valid bcp
 290 // Return -1 otherwise.
 291 // Used by profiling code, when invalid data is a possibility.
 292 // The caller is responsible for validating the Method* itself.
 293 int Method::validate_bci_from_bcp(address bcp) const {
 294   // keep bci as -1 if not a valid bci
 295   int bci = -1;
 296   if (bcp == 0 || bcp == code_base()) {
 297     // code_size() may return 0 and we allow 0 here
 298     // the method may be native
 299     bci = 0;
 300   } else if (contains(bcp)) {
 301     bci = bcp - code_base();
 302   }
 303   // Assert that if we have dodged any asserts, bci is negative.
 304   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 305   return bci;
 306 }
 307 
 308 address Method::bcp_from(int bci) const {
 309   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 310          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 311   address bcp = code_base() + bci;
 312   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 313   return bcp;
 314 }
 315 
 316 address Method::bcp_from(address bcp) const {
 317   if (is_native() && bcp == NULL) {
 318     return code_base();
 319   } else {
 320     return bcp;
 321   }
 322 }
 323 
 324 int Method::size(bool is_native) {
 325   // If native, then include pointers for native_function and signature_handler
 326   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 327   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 328   return align_metadata_size(header_size() + extra_words);
 329 }
 330 
 331 
 332 Symbol* Method::klass_name() const {
 333   return method_holder()->name();
 334 }
 335 
 336 
 337 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 338   log_trace(cds)("Iter(Method): %p", this);
 339 
 340   it->push(&_constMethod);
 341   it->push(&_method_data);
 342   it->push(&_method_counters);
 343 }
 344 
 345 // Attempt to return method oop to original state.  Clear any pointers
 346 // (to objects outside the shared spaces).  We won't be able to predict
 347 // where they should point in a new JVM.  Further initialize some
 348 // entries now in order allow them to be write protected later.
 349 
 350 void Method::remove_unshareable_info() {
 351   unlink_method();
 352 }
 353 
 354 void Method::set_vtable_index(int index) {
 355   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 356     // At runtime initialize_vtable is rerun as part of link_class_impl()
 357     // for a shared class loaded by the non-boot loader to obtain the loader
 358     // constraints based on the runtime classloaders' context.
 359     return; // don't write into the shared class
 360   } else {
 361     _vtable_index = index;
 362   }
 363 }
 364 
 365 void Method::set_itable_index(int index) {
 366   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 367     // At runtime initialize_itable is rerun as part of link_class_impl()
 368     // for a shared class loaded by the non-boot loader to obtain the loader
 369     // constraints based on the runtime classloaders' context. The dumptime
 370     // itable index should be the same as the runtime index.
 371     assert(_vtable_index == itable_index_max - index,
 372            "archived itable index is different from runtime index");
 373     return; // don’t write into the shared class
 374   } else {
 375     _vtable_index = itable_index_max - index;
 376   }
 377   assert(valid_itable_index(), "");
 378 }
 379 
 380 
 381 
 382 bool Method::was_executed_more_than(int n) {
 383   // Invocation counter is reset when the Method* is compiled.
 384   // If the method has compiled code we therefore assume it has
 385   // be excuted more than n times.
 386   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 387     // interpreter doesn't bump invocation counter of trivial methods
 388     // compiler does not bump invocation counter of compiled methods
 389     return true;
 390   }
 391   else if ((method_counters() != NULL &&
 392             method_counters()->invocation_counter()->carry()) ||
 393            (method_data() != NULL &&
 394             method_data()->invocation_counter()->carry())) {
 395     // The carry bit is set when the counter overflows and causes
 396     // a compilation to occur.  We don't know how many times
 397     // the counter has been reset, so we simply assume it has
 398     // been executed more than n times.
 399     return true;
 400   } else {
 401     return invocation_count() > n;
 402   }
 403 }
 404 
 405 void Method::print_invocation_count() {
 406   if (is_static()) tty->print("static ");
 407   if (is_final()) tty->print("final ");
 408   if (is_synchronized()) tty->print("synchronized ");
 409   if (is_native()) tty->print("native ");
 410   tty->print("%s::", method_holder()->external_name());
 411   name()->print_symbol_on(tty);
 412   signature()->print_symbol_on(tty);
 413 
 414   if (WizardMode) {
 415     // dump the size of the byte codes
 416     tty->print(" {%d}", code_size());
 417   }
 418   tty->cr();
 419 
 420   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 421   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 422   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 423 #ifndef PRODUCT
 424   if (CountCompiledCalls) {
 425     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 426   }
 427 #endif
 428 }
 429 
 430 // Build a MethodData* object to hold information about this method
 431 // collected in the interpreter.
 432 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 433   // Do not profile the method if metaspace has hit an OOM previously
 434   // allocating profiling data. Callers clear pending exception so don't
 435   // add one here.
 436   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 437     return;
 438   }
 439 
 440   // Grab a lock here to prevent multiple
 441   // MethodData*s from being created.
 442   MutexLocker ml(MethodData_lock, THREAD);
 443   if (method->method_data() == NULL) {
 444     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 445     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 446     if (HAS_PENDING_EXCEPTION) {
 447       CompileBroker::log_metaspace_failure();
 448       ClassLoaderDataGraph::set_metaspace_oom(true);
 449       return;   // return the exception (which is cleared)
 450     }
 451 
 452     method->set_method_data(method_data);
 453     if (PrintMethodData && (Verbose || WizardMode)) {
 454       ResourceMark rm(THREAD);
 455       tty->print("build_interpreter_method_data for ");
 456       method->print_name(tty);
 457       tty->cr();
 458       // At the end of the run, the MDO, full of data, will be dumped.
 459     }
 460   }
 461 }
 462 
 463 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 464   // Do not profile the method if metaspace has hit an OOM previously
 465   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 466     return NULL;
 467   }
 468 
 469   methodHandle mh(m);
 470   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 471   if (HAS_PENDING_EXCEPTION) {
 472     CompileBroker::log_metaspace_failure();
 473     ClassLoaderDataGraph::set_metaspace_oom(true);
 474     return NULL;   // return the exception (which is cleared)
 475   }
 476   if (!mh->init_method_counters(counters)) {
 477     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 478   }
 479 
 480   if (LogTouchedMethods) {
 481     mh->log_touched(CHECK_NULL);
 482   }
 483 
 484   return mh->method_counters();
 485 }
 486 
 487 bool Method::init_method_counters(MethodCounters* counters) {
 488   // Try to install a pointer to MethodCounters, return true on success.
 489   return Atomic::replace_if_null(counters, &_method_counters);
 490 }
 491 
 492 int Method::extra_stack_words() {
 493   // not an inline function, to avoid a header dependency on Interpreter
 494   return extra_stack_entries() * Interpreter::stackElementSize;
 495 }
 496 
 497 
 498 void Method::compute_size_of_parameters(Thread *thread) {
 499   ArgumentSizeComputer asc(signature());
 500   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 501 }
 502 
 503 BasicType Method::result_type() const {
 504   ResultTypeFinder rtf(signature());
 505   return rtf.type();
 506 }
 507 
 508 // ValueKlass the method is declared to return. This must not
 509 // safepoint as it is called with references live on the stack at
 510 // locations the GC is unaware of.
 511 ValueKlass* Method::returned_value_type(Thread* thread) const {
 512   SignatureStream ss(signature());
 513   while (!ss.at_return_type()) {
 514     ss.next();
 515   }
 516   Handle class_loader(thread, method_holder()->class_loader());
 517   Handle protection_domain(thread, method_holder()->protection_domain());
 518   Klass* k = NULL;
 519   {
 520     NoSafepointVerifier nsv;
 521     k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
 522   }
 523   assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
 524   return ValueKlass::cast(k);
 525 }
 526 
 527 bool Method::is_empty_method() const {
 528   return  code_size() == 1
 529       && *code_base() == Bytecodes::_return;
 530 }
 531 
 532 
 533 bool Method::is_vanilla_constructor() const {
 534   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 535   // which only calls the superclass vanilla constructor and possibly does stores of
 536   // zero constants to local fields:
 537   //
 538   //   aload_0
 539   //   invokespecial
 540   //   indexbyte1
 541   //   indexbyte2
 542   //
 543   // followed by an (optional) sequence of:
 544   //
 545   //   aload_0
 546   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 547   //   putfield
 548   //   indexbyte1
 549   //   indexbyte2
 550   //
 551   // followed by:
 552   //
 553   //   return
 554 
 555   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 556   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 557   int size = code_size();
 558   // Check if size match
 559   if (size == 0 || size % 5 != 0) return false;
 560   address cb = code_base();
 561   int last = size - 1;
 562   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 563     // Does not call superclass default constructor
 564     return false;
 565   }
 566   // Check optional sequence
 567   for (int i = 4; i < last; i += 5) {
 568     if (cb[i] != Bytecodes::_aload_0) return false;
 569     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 570     if (cb[i+2] != Bytecodes::_putfield) return false;
 571   }
 572   return true;
 573 }
 574 
 575 
 576 bool Method::compute_has_loops_flag() {
 577   BytecodeStream bcs(this);
 578   Bytecodes::Code bc;
 579 
 580   while ((bc = bcs.next()) >= 0) {
 581     switch( bc ) {
 582       case Bytecodes::_ifeq:
 583       case Bytecodes::_ifnull:
 584       case Bytecodes::_iflt:
 585       case Bytecodes::_ifle:
 586       case Bytecodes::_ifne:
 587       case Bytecodes::_ifnonnull:
 588       case Bytecodes::_ifgt:
 589       case Bytecodes::_ifge:
 590       case Bytecodes::_if_icmpeq:
 591       case Bytecodes::_if_icmpne:
 592       case Bytecodes::_if_icmplt:
 593       case Bytecodes::_if_icmpgt:
 594       case Bytecodes::_if_icmple:
 595       case Bytecodes::_if_icmpge:
 596       case Bytecodes::_if_acmpeq:
 597       case Bytecodes::_if_acmpne:
 598       case Bytecodes::_goto:
 599       case Bytecodes::_jsr:
 600         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 601         break;
 602 
 603       case Bytecodes::_goto_w:
 604       case Bytecodes::_jsr_w:
 605         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 606         break;
 607 
 608       default:
 609         break;
 610     }
 611   }
 612   _access_flags.set_loops_flag_init();
 613   return _access_flags.has_loops();
 614 }
 615 
 616 bool Method::is_final_method(AccessFlags class_access_flags) const {
 617   // or "does_not_require_vtable_entry"
 618   // default method or overpass can occur, is not final (reuses vtable entry)
 619   // private methods in classes get vtable entries for backward class compatibility.
 620   if (is_overpass() || is_default_method())  return false;
 621   return is_final() || class_access_flags.is_final();
 622 }
 623 
 624 bool Method::is_final_method() const {
 625   return is_final_method(method_holder()->access_flags());
 626 }
 627 
 628 bool Method::is_default_method() const {
 629   if (method_holder() != NULL &&
 630       method_holder()->is_interface() &&
 631       !is_abstract() && !is_private()) {
 632     return true;
 633   } else {
 634     return false;
 635   }
 636 }
 637 
 638 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 639   if (is_final_method(class_access_flags))  return true;
 640 #ifdef ASSERT
 641   ResourceMark rm;
 642   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 643   if (class_access_flags.is_interface()) {
 644       assert(is_nonv == is_static() || is_nonv == is_private(),
 645              "nonvirtual unexpected for non-static, non-private: %s",
 646              name_and_sig_as_C_string());
 647   }
 648 #endif
 649   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 650   return vtable_index() == nonvirtual_vtable_index;
 651 }
 652 
 653 bool Method::can_be_statically_bound() const {
 654   return can_be_statically_bound(method_holder()->access_flags());
 655 }
 656 
 657 bool Method::can_be_statically_bound(InstanceKlass* context) const {
 658   return (method_holder() == context) && can_be_statically_bound();
 659 }
 660 
 661 bool Method::is_accessor() const {
 662   return is_getter() || is_setter();
 663 }
 664 
 665 bool Method::is_getter() const {
 666   if (code_size() != 5) return false;
 667   if (size_of_parameters() != 1) return false;
 668   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 669   if (java_code_at(1) != Bytecodes::_getfield) return false;
 670   switch (java_code_at(4)) {
 671     case Bytecodes::_ireturn:
 672     case Bytecodes::_lreturn:
 673     case Bytecodes::_freturn:
 674     case Bytecodes::_dreturn:
 675     case Bytecodes::_areturn:
 676       break;
 677     default:
 678       return false;
 679   }
 680   return true;
 681 }
 682 
 683 bool Method::is_setter() const {
 684   if (code_size() != 6) return false;
 685   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 686   switch (java_code_at(1)) {
 687     case Bytecodes::_iload_1:
 688     case Bytecodes::_aload_1:
 689     case Bytecodes::_fload_1:
 690       if (size_of_parameters() != 2) return false;
 691       break;
 692     case Bytecodes::_dload_1:
 693     case Bytecodes::_lload_1:
 694       if (size_of_parameters() != 3) return false;
 695       break;
 696     default:
 697       return false;
 698   }
 699   if (java_code_at(2) != Bytecodes::_putfield) return false;
 700   if (java_code_at(5) != Bytecodes::_return)   return false;
 701   return true;
 702 }
 703 
 704 bool Method::is_constant_getter() const {
 705   int last_index = code_size() - 1;
 706   // Check if the first 1-3 bytecodes are a constant push
 707   // and the last bytecode is a return.
 708   return (2 <= code_size() && code_size() <= 4 &&
 709           Bytecodes::is_const(java_code_at(0)) &&
 710           Bytecodes::length_for(java_code_at(0)) == last_index &&
 711           Bytecodes::is_return(java_code_at(last_index)));
 712 }
 713 
 714 bool Method::is_object_constructor_or_class_initializer() const {
 715   return (is_object_constructor() || is_class_initializer());
 716 }
 717 
 718 bool Method::is_class_initializer() const {
 719   // For classfiles version 51 or greater, ensure that the clinit method is
 720   // static.  Non-static methods with the name "<clinit>" are not static
 721   // initializers. (older classfiles exempted for backward compatibility)
 722   return (name() == vmSymbols::class_initializer_name() &&
 723           (is_static() ||
 724            method_holder()->major_version() < 51));
 725 }
 726 
 727 // A method named <init>, if non-static, is a classic object constructor.
 728 bool Method::is_object_constructor() const {
 729    return name() == vmSymbols::object_initializer_name() && !is_static();
 730 }
 731 
 732 // A static method named <init> is a factory for an inline class.
 733 bool Method::is_static_init_factory() const {
 734    return name() == vmSymbols::object_initializer_name() && is_static();
 735 }
 736 
 737 bool Method::needs_clinit_barrier() const {
 738   return is_static() && !method_holder()->is_initialized();
 739 }
 740 
 741 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 742   int length = method->checked_exceptions_length();
 743   if (length == 0) {  // common case
 744     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 745   } else {
 746     methodHandle h_this(THREAD, method);
 747     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 748     objArrayHandle mirrors (THREAD, m_oop);
 749     for (int i = 0; i < length; i++) {
 750       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 751       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 752       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 753       mirrors->obj_at_put(i, k->java_mirror());
 754     }
 755     return mirrors;
 756   }
 757 };
 758 
 759 
 760 int Method::line_number_from_bci(int bci) const {
 761   int best_bci  =  0;
 762   int best_line = -1;
 763   if (bci == SynchronizationEntryBCI) bci = 0;
 764   if (0 <= bci && bci < code_size() && has_linenumber_table()) {
 765     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 766     // Not necessarily sorted and not necessarily one-to-one.
 767     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 768     while (stream.read_pair()) {
 769       if (stream.bci() == bci) {
 770         // perfect match
 771         return stream.line();
 772       } else {
 773         // update best_bci/line
 774         if (stream.bci() < bci && stream.bci() >= best_bci) {
 775           best_bci  = stream.bci();
 776           best_line = stream.line();
 777         }
 778       }
 779     }
 780   }
 781   return best_line;
 782 }
 783 
 784 
 785 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 786   if( constants()->tag_at(klass_index).is_unresolved_klass()) {
 787     Thread *thread = Thread::current();
 788     Symbol* klass_name = constants()->klass_name_at(klass_index);
 789     Handle loader(thread, method_holder()->class_loader());
 790     Handle prot  (thread, method_holder()->protection_domain());
 791     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 792   } else {
 793     return true;
 794   }
 795 }
 796 
 797 
 798 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 799   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 800   if (must_be_resolved) {
 801     // Make sure klass is resolved in constantpool.
 802     if (constants()->tag_at(klass_index).is_unresolved_klass()) {
 803       return false;
 804     }
 805   }
 806   return is_klass_loaded_by_klass_index(klass_index);
 807 }
 808 
 809 
 810 void Method::set_native_function(address function, bool post_event_flag) {
 811   assert(function != NULL, "use clear_native_function to unregister natives");
 812   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 813   address* native_function = native_function_addr();
 814 
 815   // We can see racers trying to place the same native function into place. Once
 816   // is plenty.
 817   address current = *native_function;
 818   if (current == function) return;
 819   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 820       function != NULL) {
 821     // native_method_throw_unsatisfied_link_error_entry() should only
 822     // be passed when post_event_flag is false.
 823     assert(function !=
 824       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 825       "post_event_flag mis-match");
 826 
 827     // post the bind event, and possible change the bind function
 828     JvmtiExport::post_native_method_bind(this, &function);
 829   }
 830   *native_function = function;
 831   // This function can be called more than once. We must make sure that we always
 832   // use the latest registered method -> check if a stub already has been generated.
 833   // If so, we have to make it not_entrant.
 834   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 835   if (nm != NULL) {
 836     nm->make_not_entrant();
 837   }
 838 }
 839 
 840 
 841 bool Method::has_native_function() const {
 842   if (is_method_handle_intrinsic())
 843     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 844   address func = native_function();
 845   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 846 }
 847 
 848 
 849 void Method::clear_native_function() {
 850   // Note: is_method_handle_intrinsic() is allowed here.
 851   set_native_function(
 852     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 853     !native_bind_event_is_interesting);
 854   this->unlink_code();
 855 }
 856 
 857 address Method::critical_native_function() {
 858   methodHandle mh(this);
 859   return NativeLookup::lookup_critical_entry(mh);
 860 }
 861 
 862 
 863 void Method::set_signature_handler(address handler) {
 864   address* signature_handler =  signature_handler_addr();
 865   *signature_handler = handler;
 866 }
 867 
 868 
 869 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 870   assert(reason != NULL, "must provide a reason");
 871   if (PrintCompilation && report) {
 872     ttyLocker ttyl;
 873     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 874     if (comp_level == CompLevel_all) {
 875       tty->print("all levels ");
 876     } else {
 877       tty->print("levels ");
 878       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 879         tty->print("%d ", i);
 880       }
 881     }
 882     this->print_short_name(tty);
 883     int size = this->code_size();
 884     if (size > 0) {
 885       tty->print(" (%d bytes)", size);
 886     }
 887     if (reason != NULL) {
 888       tty->print("   %s", reason);
 889     }
 890     tty->cr();
 891   }
 892   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 893     ttyLocker ttyl;
 894     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 895                      os::current_thread_id(), is_osr, comp_level);
 896     if (reason != NULL) {
 897       xtty->print(" reason=\'%s\'", reason);
 898     }
 899     xtty->method(this);
 900     xtty->stamp();
 901     xtty->end_elem();
 902   }
 903 }
 904 
 905 bool Method::is_always_compilable() const {
 906   // Generated adapters must be compiled
 907   if (is_method_handle_intrinsic() && is_synthetic()) {
 908     assert(!is_not_c1_compilable(), "sanity check");
 909     assert(!is_not_c2_compilable(), "sanity check");
 910     return true;
 911   }
 912 
 913   return false;
 914 }
 915 
 916 bool Method::is_not_compilable(int comp_level) const {
 917   if (number_of_breakpoints() > 0)
 918     return true;
 919   if (is_always_compilable())
 920     return false;
 921   if (comp_level == CompLevel_any)
 922     return is_not_c1_compilable() || is_not_c2_compilable();
 923   if (is_c1_compile(comp_level))
 924     return is_not_c1_compilable();
 925   if (is_c2_compile(comp_level))
 926     return is_not_c2_compilable();
 927   return false;
 928 }
 929 
 930 // call this when compiler finds that this method is not compilable
 931 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
 932   if (is_always_compilable()) {
 933     // Don't mark a method which should be always compilable
 934     return;
 935   }
 936   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 937   if (comp_level == CompLevel_all) {
 938     set_not_c1_compilable();
 939     set_not_c2_compilable();
 940   } else {
 941     if (is_c1_compile(comp_level))
 942       set_not_c1_compilable();
 943     if (is_c2_compile(comp_level))
 944       set_not_c2_compilable();
 945   }
 946   CompilationPolicy::policy()->disable_compilation(this);
 947   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 948 }
 949 
 950 bool Method::is_not_osr_compilable(int comp_level) const {
 951   if (is_not_compilable(comp_level))
 952     return true;
 953   if (comp_level == CompLevel_any)
 954     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 955   if (is_c1_compile(comp_level))
 956     return is_not_c1_osr_compilable();
 957   if (is_c2_compile(comp_level))
 958     return is_not_c2_osr_compilable();
 959   return false;
 960 }
 961 
 962 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
 963   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 964   if (comp_level == CompLevel_all) {
 965     set_not_c1_osr_compilable();
 966     set_not_c2_osr_compilable();
 967   } else {
 968     if (is_c1_compile(comp_level))
 969       set_not_c1_osr_compilable();
 970     if (is_c2_compile(comp_level))
 971       set_not_c2_osr_compilable();
 972   }
 973   CompilationPolicy::policy()->disable_compilation(this);
 974   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 975 }
 976 
 977 // Revert to using the interpreter and clear out the nmethod
 978 void Method::clear_code() {
 979   // this may be NULL if c2i adapters have not been made yet
 980   // Only should happen at allocate time.
 981   if (adapter() == NULL) {
 982     _from_compiled_entry    = NULL;
 983     _from_compiled_value_entry = NULL;
 984     _from_compiled_value_ro_entry = NULL;
 985   } else {
 986     _from_compiled_entry    = adapter()->get_c2i_entry();
 987     _from_compiled_value_entry = adapter()->get_c2i_value_entry();
 988     _from_compiled_value_ro_entry = adapter()->get_c2i_value_ro_entry();
 989   }
 990   OrderAccess::storestore();
 991   _from_interpreted_entry = _i2i_entry;
 992   OrderAccess::storestore();
 993   _code = NULL;
 994 }
 995 
 996 void Method::unlink_code(CompiledMethod *compare) {
 997   MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
 998   // We need to check if either the _code or _from_compiled_code_entry_point
 999   // refer to this nmethod because there is a race in setting these two fields
1000   // in Method* as seen in bugid 4947125.
1001   // If the vep() points to the zombie nmethod, the memory for the nmethod
1002   // could be flushed and the compiler and vtable stubs could still call
1003   // through it.
1004   if (code() == compare ||
1005       from_compiled_entry() == compare->verified_entry_point()) {
1006     clear_code();
1007   }
1008 }
1009 
1010 void Method::unlink_code() {
1011   MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1012   clear_code();
1013 }
1014 
1015 #if INCLUDE_CDS
1016 // Called by class data sharing to remove any entry points (which are not shared)
1017 void Method::unlink_method() {
1018   _code = NULL;
1019 
1020   assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
1021   // Set the values to what they should be at run time. Note that
1022   // this Method can no longer be executed during dump time.
1023   _i2i_entry = Interpreter::entry_for_cds_method(this);
1024   _from_interpreted_entry = _i2i_entry;
1025 
1026   if (DynamicDumpSharedSpaces) {
1027     assert(_from_compiled_entry != NULL, "sanity");
1028   } else {
1029     // TODO: Simplify the adapter trampoline allocation for static archiving.
1030     //       Remove the use of CDSAdapterHandlerEntry.
1031     CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
1032     constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
1033     _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
1034     assert(*((int*)_from_compiled_entry) == 0,
1035            "must be NULL during dump time, to be initialized at run time");
1036     _from_compiled_value_ro_entry = cds_adapter->get_c2i_entry_trampoline(); // FIXME - doesn't work if you have value args!
1037     assert(*((int*)_from_compiled_value_ro_entry) == 0,
1038            "must be NULL during dump time, to be initialized at run time");
1039     _from_compiled_value_entry  = cds_adapter->get_c2i_entry_trampoline(); // FIXME - doesn't work if you have value args (or this is value type)!
1040     assert(*((int*)_from_compiled_value_entry) == 0,
1041            "must be NULL during dump time, to be initialized at run time");
1042     assert(!method_holder()->is_value(), "FIXME: valuetype not supported by CDS");
1043   }
1044 
1045   if (is_native()) {
1046     *native_function_addr() = NULL;
1047     set_signature_handler(NULL);
1048   }
1049   NOT_PRODUCT(set_compiled_invocation_count(0);)
1050 
1051   set_method_data(NULL);
1052   clear_method_counters();
1053 }
1054 #endif
1055 
1056 /****************************************************************************
1057 // The following illustrates how the entries work for CDS shared Methods:
1058 //
1059 // Our goal is to delay writing into a shared Method until it's compiled.
1060 // Hence, we want to determine the initial values for _i2i_entry,
1061 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1062 //
1063 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1064 // They also have similar signatures so that they will share the same
1065 // AdapterHandlerEntry.
1066 //
1067 // _adapter_trampoline points to a fixed location in the RW section of
1068 // the CDS archive. This location initially contains a NULL pointer. When the
1069 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1070 // dynamically, and its c2i/i2c entries are generated.
1071 //
1072 // _i2i_entry and _from_interpreted_entry initially points to the same
1073 // (fixed) location in the CODE section of the CDS archive. This contains
1074 // an unconditional branch to the actual entry for "zero_locals", which is
1075 // generated at run time and may be on an arbitrary address. Thus, the
1076 // unconditional branch is also generated at run time to jump to the correct
1077 // address.
1078 //
1079 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1080 // section. This address has enough space for an unconditional branch
1081 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1082 // initialized, and the address for the actual c2i_entry is known, we emit a
1083 // branch instruction here to branch to the actual c2i_entry.
1084 //
1085 // The effect of the extra branch on the i2i and c2i entries is negligible.
1086 //
1087 // The reason for putting _adapter_trampoline in RO is many shared Methods
1088 // share the same AdapterHandlerEntry, so we can save space in the RW section
1089 // by having the extra indirection.
1090 
1091 
1092 [Method A: RW]
1093   _constMethod ----> [ConstMethod: RO]
1094                        _adapter_trampoline -----------+
1095                                                       |
1096   _i2i_entry              (same value as method B)    |
1097   _from_interpreted_entry (same value as method B)    |
1098   _from_compiled_entry    (same value as method B)    |
1099                                                       |
1100                                                       |
1101 [Method B: RW]                               +--------+
1102   _constMethod ----> [ConstMethod: RO]       |
1103                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1104                                                                                  |
1105                                                  +-------------------------------+
1106                                                  |
1107                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1108                                                               _fingerprint
1109                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1110  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1111  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1112          |                |                                                             |                 |
1113          |                |  (_cds_entry_table: CODE)                                   |                 |
1114          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1115          |                |                               (allocated at run time)       |                 |
1116          |                |  ...                           [asm code ...]               |                 |
1117          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1118          |                                                                              |                 |
1119          |                                                                              |                 |
1120          +-[compiled]-------------------------------------------------------------------+                 |
1121                                                                                                           |
1122  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1123                                     [jmp c2i_entry] ------------------------------------------------------+
1124 
1125 ***/
1126 
1127 // Called when the method_holder is getting linked. Setup entrypoints so the method
1128 // is ready to be called from interpreter, compiler, and vtables.
1129 void Method::link_method(const methodHandle& h_method, TRAPS) {
1130   // If the code cache is full, we may reenter this function for the
1131   // leftover methods that weren't linked.
1132   if (is_shared()) {
1133     address entry = Interpreter::entry_for_cds_method(h_method);
1134     assert(entry != NULL && entry == _i2i_entry,
1135            "should be correctly set during dump time");
1136     if (adapter() != NULL) {
1137       return;
1138     }
1139     assert(entry == _from_interpreted_entry,
1140            "should be correctly set during dump time");
1141   } else if (_i2i_entry != NULL) {
1142     return;
1143   }
1144   assert( _code == NULL, "nothing compiled yet" );
1145 
1146   // Setup interpreter entrypoint
1147   assert(this == h_method(), "wrong h_method()" );
1148 
1149   if (!is_shared()) {
1150     assert(adapter() == NULL, "init'd to NULL");
1151     address entry = Interpreter::entry_for_method(h_method);
1152     assert(entry != NULL, "interpreter entry must be non-null");
1153     // Sets both _i2i_entry and _from_interpreted_entry
1154     set_interpreter_entry(entry);
1155   }
1156 
1157   // Don't overwrite already registered native entries.
1158   if (is_native() && !has_native_function()) {
1159     set_native_function(
1160       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1161       !native_bind_event_is_interesting);
1162   }
1163 
1164   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1165   // special handling of vtables.  An alternative is to make adapters more
1166   // lazily by calling make_adapter() from from_compiled_entry() for the
1167   // normal calls.  For vtable calls life gets more complicated.  When a
1168   // call-site goes mega-morphic we need adapters in all methods which can be
1169   // called from the vtable.  We need adapters on such methods that get loaded
1170   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1171   // problem we'll make these lazily later.
1172   (void) make_adapters(h_method, CHECK);
1173 
1174   // ONLY USE the h_method now as make_adapter may have blocked
1175 
1176 }
1177 
1178 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1179   // Adapters for compiled code are made eagerly here.  They are fairly
1180   // small (generally < 100 bytes) and quick to make (and cached and shared)
1181   // so making them eagerly shouldn't be too expensive.
1182   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1183   if (adapter == NULL ) {
1184     if (!is_init_completed()) {
1185       // Don't throw exceptions during VM initialization because java.lang.* classes
1186       // might not have been initialized, causing problems when constructing the
1187       // Java exception object.
1188       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1189     } else {
1190       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1191     }
1192   }
1193 
1194   if (mh->is_shared()) {
1195     assert(mh->adapter() == adapter, "must be");
1196     assert(mh->_from_compiled_entry != NULL, "must be");
1197     assert(mh->_from_compiled_value_entry != NULL, "must be");
1198     assert(mh->_from_compiled_value_ro_entry != NULL, "must be");
1199   } else {
1200     mh->set_adapter_entry(adapter);
1201     mh->_from_compiled_entry = adapter->get_c2i_entry();
1202     mh->_from_compiled_value_entry = adapter->get_c2i_value_entry();
1203     mh->_from_compiled_value_ro_entry = adapter->get_c2i_value_ro_entry();
1204   }
1205   return adapter->get_c2i_entry();
1206 }
1207 
1208 void Method::restore_unshareable_info(TRAPS) {
1209   assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1210 
1211   // Since restore_unshareable_info can be called more than once for a method, don't
1212   // redo any work.
1213   if (adapter() == NULL) {
1214     methodHandle mh(THREAD, this);
1215     link_method(mh, CHECK);
1216   }
1217 }
1218 
1219 address Method::from_compiled_entry_no_trampoline(bool caller_is_c1) const {
1220   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1221   if (caller_is_c1) {
1222     // C1 - value arguments are passed as objects
1223     if (code) {
1224       return code->verified_value_entry_point();
1225     } else {
1226       return adapter()->get_c2i_value_entry();
1227     }
1228   } else {
1229     // C2 - value arguments may be passed as fields
1230     if (code) {
1231       return code->verified_entry_point();
1232     } else {
1233       return adapter()->get_c2i_entry();
1234     }
1235   }
1236 }
1237 
1238 // The verified_code_entry() must be called when a invoke is resolved
1239 // on this method.
1240 
1241 // It returns the compiled code entry point, after asserting not null.
1242 // This function is called after potential safepoints so that nmethod
1243 // or adapter that it points to is still live and valid.
1244 // This function must not hit a safepoint!
1245 address Method::verified_code_entry() {
1246   debug_only(NoSafepointVerifier nsv;)
1247   assert(_from_compiled_entry != NULL, "must be set");
1248   return _from_compiled_entry;
1249 }
1250 
1251 address Method::verified_value_code_entry() {
1252   debug_only(NoSafepointVerifier nsv;)
1253   assert(_from_compiled_value_entry != NULL, "must be set");
1254   return _from_compiled_value_entry;
1255 }
1256 
1257 address Method::verified_value_ro_code_entry() {
1258   debug_only(NoSafepointVerifier nsv;)
1259   assert(_from_compiled_value_ro_entry != NULL, "must be set");
1260   return _from_compiled_value_ro_entry;
1261 }
1262 
1263 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1264 // (could be racing a deopt).
1265 // Not inline to avoid circular ref.
1266 bool Method::check_code() const {
1267   // cached in a register or local.  There's a race on the value of the field.
1268   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1269   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1270 }
1271 
1272 // Install compiled code.  Instantly it can execute.
1273 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1274   MutexLocker pl(CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1275   assert( code, "use clear_code to remove code" );
1276   assert( mh->check_code(), "" );
1277 
1278   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1279 
1280   // These writes must happen in this order, because the interpreter will
1281   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1282   // which jumps to _from_compiled_entry.
1283   mh->_code = code;             // Assign before allowing compiled code to exec
1284 
1285   int comp_level = code->comp_level();
1286   // In theory there could be a race here. In practice it is unlikely
1287   // and not worth worrying about.
1288   if (comp_level > mh->highest_comp_level()) {
1289     mh->set_highest_comp_level(comp_level);
1290   }
1291 
1292   OrderAccess::storestore();
1293   mh->_from_compiled_entry = code->verified_entry_point();
1294   mh->_from_compiled_value_entry = code->verified_value_entry_point();
1295   mh->_from_compiled_value_ro_entry = code->verified_value_ro_entry_point();
1296   OrderAccess::storestore();
1297   // Instantly compiled code can execute.
1298   if (!mh->is_method_handle_intrinsic())
1299     mh->_from_interpreted_entry = mh->get_i2c_entry();
1300 }
1301 
1302 
1303 bool Method::is_overridden_in(Klass* k) const {
1304   InstanceKlass* ik = InstanceKlass::cast(k);
1305 
1306   if (ik->is_interface()) return false;
1307 
1308   // If method is an interface, we skip it - except if it
1309   // is a miranda method
1310   if (method_holder()->is_interface()) {
1311     // Check that method is not a miranda method
1312     if (ik->lookup_method(name(), signature()) == NULL) {
1313       // No implementation exist - so miranda method
1314       return false;
1315     }
1316     return true;
1317   }
1318 
1319   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1320   if (!has_vtable_index()) {
1321     return false;
1322   } else {
1323     Method* vt_m = ik->method_at_vtable(vtable_index());
1324     return vt_m != this;
1325   }
1326 }
1327 
1328 
1329 // give advice about whether this Method* should be cached or not
1330 bool Method::should_not_be_cached() const {
1331   if (is_old()) {
1332     // This method has been redefined. It is either EMCP or obsolete
1333     // and we don't want to cache it because that would pin the method
1334     // down and prevent it from being collectible if and when it
1335     // finishes executing.
1336     return true;
1337   }
1338 
1339   // caching this method should be just fine
1340   return false;
1341 }
1342 
1343 
1344 /**
1345  *  Returns true if this is one of the specially treated methods for
1346  *  security related stack walks (like Reflection.getCallerClass).
1347  */
1348 bool Method::is_ignored_by_security_stack_walk() const {
1349   if (intrinsic_id() == vmIntrinsics::_invoke) {
1350     // This is Method.invoke() -- ignore it
1351     return true;
1352   }
1353   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1354     // This is an auxilary frame -- ignore it
1355     return true;
1356   }
1357   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1358     // This is an internal adapter frame for method handles -- ignore it
1359     return true;
1360   }
1361   return false;
1362 }
1363 
1364 
1365 // Constant pool structure for invoke methods:
1366 enum {
1367   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1368   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1369   _imcp_limit
1370 };
1371 
1372 // Test if this method is an MH adapter frame generated by Java code.
1373 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1374 bool Method::is_compiled_lambda_form() const {
1375   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1376 }
1377 
1378 // Test if this method is an internal MH primitive method.
1379 bool Method::is_method_handle_intrinsic() const {
1380   vmIntrinsics::ID iid = intrinsic_id();
1381   return (MethodHandles::is_signature_polymorphic(iid) &&
1382           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1383 }
1384 
1385 bool Method::has_member_arg() const {
1386   vmIntrinsics::ID iid = intrinsic_id();
1387   return (MethodHandles::is_signature_polymorphic(iid) &&
1388           MethodHandles::has_member_arg(iid));
1389 }
1390 
1391 // Make an instance of a signature-polymorphic internal MH primitive.
1392 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1393                                                          Symbol* signature,
1394                                                          TRAPS) {
1395   ResourceMark rm;
1396   methodHandle empty;
1397 
1398   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1399   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1400   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1401   if (TraceMethodHandles) {
1402     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1403   }
1404 
1405   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1406   name->increment_refcount();
1407   signature->increment_refcount();
1408 
1409   int cp_length = _imcp_limit;
1410   ClassLoaderData* loader_data = holder->class_loader_data();
1411   constantPoolHandle cp;
1412   {
1413     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1414     cp = constantPoolHandle(THREAD, cp_oop);
1415   }
1416   cp->set_pool_holder(holder);
1417   cp->symbol_at_put(_imcp_invoke_name,       name);
1418   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1419   cp->set_has_preresolution();
1420 
1421   // decide on access bits:  public or not?
1422   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1423   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1424   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1425   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1426 
1427   methodHandle m;
1428   {
1429     InlineTableSizes sizes;
1430     Method* m_oop = Method::allocate(loader_data, 0,
1431                                      accessFlags_from(flags_bits), &sizes,
1432                                      ConstMethod::NORMAL, CHECK_(empty));
1433     m = methodHandle(THREAD, m_oop);
1434   }
1435   m->set_constants(cp());
1436   m->set_name_index(_imcp_invoke_name);
1437   m->set_signature_index(_imcp_invoke_signature);
1438   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1439   assert(m->signature() == signature, "");
1440   ResultTypeFinder rtf(signature);
1441   m->constMethod()->set_result_type(rtf.type());
1442   m->compute_size_of_parameters(THREAD);
1443   m->init_intrinsic_id();
1444   assert(m->is_method_handle_intrinsic(), "");
1445 #ifdef ASSERT
1446   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1447   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1448   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1449 #endif //ASSERT
1450 
1451   // Finally, set up its entry points.
1452   assert(m->can_be_statically_bound(), "");
1453   m->set_vtable_index(Method::nonvirtual_vtable_index);
1454   m->link_method(m, CHECK_(empty));
1455 
1456   if (TraceMethodHandles && (Verbose || WizardMode)) {
1457     ttyLocker ttyl;
1458     m->print_on(tty);
1459   }
1460 
1461   return m;
1462 }
1463 
1464 Klass* Method::check_non_bcp_klass(Klass* klass) {
1465   if (klass != NULL && klass->class_loader() != NULL) {
1466     if (klass->is_objArray_klass())
1467       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1468     return klass;
1469   }
1470   return NULL;
1471 }
1472 
1473 
1474 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1475                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1476   // Code below does not work for native methods - they should never get rewritten anyway
1477   assert(!m->is_native(), "cannot rewrite native methods");
1478   // Allocate new Method*
1479   AccessFlags flags = m->access_flags();
1480 
1481   ConstMethod* cm = m->constMethod();
1482   int checked_exceptions_len = cm->checked_exceptions_length();
1483   int localvariable_len = cm->localvariable_table_length();
1484   int exception_table_len = cm->exception_table_length();
1485   int method_parameters_len = cm->method_parameters_length();
1486   int method_annotations_len = cm->method_annotations_length();
1487   int parameter_annotations_len = cm->parameter_annotations_length();
1488   int type_annotations_len = cm->type_annotations_length();
1489   int default_annotations_len = cm->default_annotations_length();
1490 
1491   InlineTableSizes sizes(
1492       localvariable_len,
1493       new_compressed_linenumber_size,
1494       exception_table_len,
1495       checked_exceptions_len,
1496       method_parameters_len,
1497       cm->generic_signature_index(),
1498       method_annotations_len,
1499       parameter_annotations_len,
1500       type_annotations_len,
1501       default_annotations_len,
1502       0);
1503 
1504   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1505   Method* newm_oop = Method::allocate(loader_data,
1506                                       new_code_length,
1507                                       flags,
1508                                       &sizes,
1509                                       m->method_type(),
1510                                       CHECK_(methodHandle()));
1511   methodHandle newm (THREAD, newm_oop);
1512 
1513   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1514   ConstMethod* newcm = newm->constMethod();
1515   int new_const_method_size = newm->constMethod()->size();
1516 
1517   // This works because the source and target are both Methods. Some compilers
1518   // (e.g., clang) complain that the target vtable pointer will be stomped,
1519   // so cast away newm()'s and m()'s Methodness.
1520   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1521 
1522   // Create shallow copy of ConstMethod.
1523   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1524 
1525   // Reset correct method/const method, method size, and parameter info
1526   newm->set_constMethod(newcm);
1527   newm->constMethod()->set_code_size(new_code_length);
1528   newm->constMethod()->set_constMethod_size(new_const_method_size);
1529   assert(newm->code_size() == new_code_length, "check");
1530   assert(newm->method_parameters_length() == method_parameters_len, "check");
1531   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1532   assert(newm->exception_table_length() == exception_table_len, "check");
1533   assert(newm->localvariable_table_length() == localvariable_len, "check");
1534   // Copy new byte codes
1535   memcpy(newm->code_base(), new_code, new_code_length);
1536   // Copy line number table
1537   if (new_compressed_linenumber_size > 0) {
1538     memcpy(newm->compressed_linenumber_table(),
1539            new_compressed_linenumber_table,
1540            new_compressed_linenumber_size);
1541   }
1542   // Copy method_parameters
1543   if (method_parameters_len > 0) {
1544     memcpy(newm->method_parameters_start(),
1545            m->method_parameters_start(),
1546            method_parameters_len * sizeof(MethodParametersElement));
1547   }
1548   // Copy checked_exceptions
1549   if (checked_exceptions_len > 0) {
1550     memcpy(newm->checked_exceptions_start(),
1551            m->checked_exceptions_start(),
1552            checked_exceptions_len * sizeof(CheckedExceptionElement));
1553   }
1554   // Copy exception table
1555   if (exception_table_len > 0) {
1556     memcpy(newm->exception_table_start(),
1557            m->exception_table_start(),
1558            exception_table_len * sizeof(ExceptionTableElement));
1559   }
1560   // Copy local variable number table
1561   if (localvariable_len > 0) {
1562     memcpy(newm->localvariable_table_start(),
1563            m->localvariable_table_start(),
1564            localvariable_len * sizeof(LocalVariableTableElement));
1565   }
1566   // Copy stackmap table
1567   if (m->has_stackmap_table()) {
1568     int code_attribute_length = m->stackmap_data()->length();
1569     Array<u1>* stackmap_data =
1570       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1571     memcpy((void*)stackmap_data->adr_at(0),
1572            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1573     newm->set_stackmap_data(stackmap_data);
1574   }
1575 
1576   // copy annotations over to new method
1577   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1578   return newm;
1579 }
1580 
1581 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1582   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1583   // because we are not loading from core libraries
1584   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1585   // which does not use the class default class loader so we check for its loader here
1586   const InstanceKlass* ik = InstanceKlass::cast(holder);
1587   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1588     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1589   }
1590 
1591   // see if the klass name is well-known:
1592   Symbol* klass_name = ik->name();
1593   return vmSymbols::find_sid(klass_name);
1594 }
1595 
1596 void Method::init_intrinsic_id() {
1597   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1598   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1599   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1600   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1601 
1602   // the klass name is well-known:
1603   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1604   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1605 
1606   // ditto for method and signature:
1607   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1608   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1609       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1610       && name_id == vmSymbols::NO_SID) {
1611     return;
1612   }
1613   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1614   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1615       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1616       && sig_id == vmSymbols::NO_SID) {
1617     return;
1618   }
1619   jshort flags = access_flags().as_short();
1620 
1621   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1622   if (id != vmIntrinsics::_none) {
1623     set_intrinsic_id(id);
1624     if (id == vmIntrinsics::_Class_cast) {
1625       // Even if the intrinsic is rejected, we want to inline this simple method.
1626       set_force_inline(true);
1627     }
1628     return;
1629   }
1630 
1631   // A few slightly irregular cases:
1632   switch (klass_id) {
1633   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1634     // Second chance: check in regular Math.
1635     switch (name_id) {
1636     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1637     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1638     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1639       // pretend it is the corresponding method in the non-strict class:
1640       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1641       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1642       break;
1643     default:
1644       break;
1645     }
1646     break;
1647 
1648   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1649   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1650   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1651     if (!is_native())  break;
1652     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1653     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1654       id = vmIntrinsics::_none;
1655     break;
1656 
1657   default:
1658     break;
1659   }
1660 
1661   if (id != vmIntrinsics::_none) {
1662     // Set up its iid.  It is an alias method.
1663     set_intrinsic_id(id);
1664     return;
1665   }
1666 }
1667 
1668 // These two methods are static since a GC may move the Method
1669 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1670   if (!THREAD->can_call_java()) {
1671     // There is nothing useful this routine can do from within the Compile thread.
1672     // Hopefully, the signature contains only well-known classes.
1673     // We could scan for this and return true/false, but the caller won't care.
1674     return false;
1675   }
1676   bool sig_is_loaded = true;
1677   Handle class_loader(THREAD, m->method_holder()->class_loader());
1678   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1679   ResourceMark rm(THREAD);
1680   Symbol*  signature = m->signature();
1681   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1682     if (ss.is_object()) {
1683       Symbol* sym = ss.as_symbol();
1684       Symbol*  name  = sym;
1685       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1686                                              protection_domain, THREAD);
1687       // We are loading classes eagerly. If a ClassNotFoundException or
1688       // a LinkageError was generated, be sure to ignore it.
1689       if (HAS_PENDING_EXCEPTION) {
1690         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1691             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1692           CLEAR_PENDING_EXCEPTION;
1693         } else {
1694           return false;
1695         }
1696       }
1697       if( klass == NULL) { sig_is_loaded = false; }
1698     }
1699   }
1700   return sig_is_loaded;
1701 }
1702 
1703 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1704   Handle class_loader(THREAD, m->method_holder()->class_loader());
1705   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1706   ResourceMark rm(THREAD);
1707   Symbol*  signature = m->signature();
1708   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1709     if (ss.type() == T_OBJECT) {
1710       Symbol* name = ss.as_symbol_or_null();
1711       if (name == NULL) return true;
1712       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1713       if (klass == NULL) return true;
1714     }
1715   }
1716   return false;
1717 }
1718 
1719 // Exposed so field engineers can debug VM
1720 void Method::print_short_name(outputStream* st) {
1721   ResourceMark rm;
1722 #ifdef PRODUCT
1723   st->print(" %s::", method_holder()->external_name());
1724 #else
1725   st->print(" %s::", method_holder()->internal_name());
1726 #endif
1727   name()->print_symbol_on(st);
1728   if (WizardMode) signature()->print_symbol_on(st);
1729   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1730     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1731 }
1732 
1733 // Comparer for sorting an object array containing
1734 // Method*s.
1735 static int method_comparator(Method* a, Method* b) {
1736   return a->name()->fast_compare(b->name());
1737 }
1738 
1739 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1740 // default_methods also uses this without the ordering for fast find_method
1741 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1742   int length = methods->length();
1743   if (length > 1) {
1744     {
1745       NoSafepointVerifier nsv;
1746       QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1747     }
1748     // Reset method ordering
1749     if (set_idnums) {
1750       for (int i = 0; i < length; i++) {
1751         Method* m = methods->at(i);
1752         m->set_method_idnum(i);
1753         m->set_orig_method_idnum(i);
1754       }
1755     }
1756   }
1757 }
1758 
1759 //-----------------------------------------------------------------------------------
1760 // Non-product code unless JVM/TI needs it
1761 
1762 #if !defined(PRODUCT) || INCLUDE_JVMTI
1763 class SignatureTypePrinter : public SignatureTypeNames {
1764  private:
1765   outputStream* _st;
1766   bool _use_separator;
1767 
1768   void type_name(const char* name) {
1769     if (_use_separator) _st->print(", ");
1770     _st->print("%s", name);
1771     _use_separator = true;
1772   }
1773 
1774  public:
1775   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1776     _st = st;
1777     _use_separator = false;
1778   }
1779 
1780   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1781   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1782 };
1783 
1784 
1785 void Method::print_name(outputStream* st) {
1786   Thread *thread = Thread::current();
1787   ResourceMark rm(thread);
1788   st->print("%s ", is_static() ? "static" : "virtual");
1789   if (WizardMode) {
1790     st->print("%s.", method_holder()->internal_name());
1791     name()->print_symbol_on(st);
1792     signature()->print_symbol_on(st);
1793   } else {
1794     SignatureTypePrinter sig(signature(), st);
1795     sig.print_returntype();
1796     st->print(" %s.", method_holder()->internal_name());
1797     name()->print_symbol_on(st);
1798     st->print("(");
1799     sig.print_parameters();
1800     st->print(")");
1801   }
1802 }
1803 #endif // !PRODUCT || INCLUDE_JVMTI
1804 
1805 
1806 void Method::print_codes_on(outputStream* st) const {
1807   print_codes_on(0, code_size(), st);
1808 }
1809 
1810 void Method::print_codes_on(int from, int to, outputStream* st) const {
1811   Thread *thread = Thread::current();
1812   ResourceMark rm(thread);
1813   methodHandle mh (thread, (Method*)this);
1814   BytecodeStream s(mh);
1815   s.set_interval(from, to);
1816   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1817   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1818 }
1819 
1820 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1821   _bci = 0;
1822   _line = 0;
1823 };
1824 
1825 bool CompressedLineNumberReadStream::read_pair() {
1826   jubyte next = read_byte();
1827   // Check for terminator
1828   if (next == 0) return false;
1829   if (next == 0xFF) {
1830     // Escape character, regular compression used
1831     _bci  += read_signed_int();
1832     _line += read_signed_int();
1833   } else {
1834     // Single byte compression used
1835     _bci  += next >> 3;
1836     _line += next & 0x7;
1837   }
1838   return true;
1839 }
1840 
1841 #if INCLUDE_JVMTI
1842 
1843 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1844   BreakpointInfo* bp = method_holder()->breakpoints();
1845   for (; bp != NULL; bp = bp->next()) {
1846     if (bp->match(this, bci)) {
1847       return bp->orig_bytecode();
1848     }
1849   }
1850   {
1851     ResourceMark rm;
1852     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1853   }
1854   return Bytecodes::_shouldnotreachhere;
1855 }
1856 
1857 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1858   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1859   BreakpointInfo* bp = method_holder()->breakpoints();
1860   for (; bp != NULL; bp = bp->next()) {
1861     if (bp->match(this, bci)) {
1862       bp->set_orig_bytecode(code);
1863       // and continue, in case there is more than one
1864     }
1865   }
1866 }
1867 
1868 void Method::set_breakpoint(int bci) {
1869   InstanceKlass* ik = method_holder();
1870   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1871   bp->set_next(ik->breakpoints());
1872   ik->set_breakpoints(bp);
1873   // do this last:
1874   bp->set(this);
1875 }
1876 
1877 static void clear_matches(Method* m, int bci) {
1878   InstanceKlass* ik = m->method_holder();
1879   BreakpointInfo* prev_bp = NULL;
1880   BreakpointInfo* next_bp;
1881   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1882     next_bp = bp->next();
1883     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1884     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1885       // do this first:
1886       bp->clear(m);
1887       // unhook it
1888       if (prev_bp != NULL)
1889         prev_bp->set_next(next_bp);
1890       else
1891         ik->set_breakpoints(next_bp);
1892       delete bp;
1893       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1894       // at same location. So we have multiple matching (method_index and bci)
1895       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1896       // breakpoint for clear_breakpoint request and keep all other method versions
1897       // BreakpointInfo for future clear_breakpoint request.
1898       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1899       // which is being called when class is unloaded. We delete all the Breakpoint
1900       // information for all versions of method. We may not correctly restore the original
1901       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1902       // so these methods won't be used anymore.
1903       if (bci >= 0) {
1904         break;
1905       }
1906     } else {
1907       // This one is a keeper.
1908       prev_bp = bp;
1909     }
1910   }
1911 }
1912 
1913 void Method::clear_breakpoint(int bci) {
1914   assert(bci >= 0, "");
1915   clear_matches(this, bci);
1916 }
1917 
1918 void Method::clear_all_breakpoints() {
1919   clear_matches(this, -1);
1920 }
1921 
1922 #endif // INCLUDE_JVMTI
1923 
1924 int Method::invocation_count() {
1925   MethodCounters *mcs = method_counters();
1926   if (TieredCompilation) {
1927     MethodData* const mdo = method_data();
1928     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1929         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1930       return InvocationCounter::count_limit;
1931     } else {
1932       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1933              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1934     }
1935   } else {
1936     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1937   }
1938 }
1939 
1940 int Method::backedge_count() {
1941   MethodCounters *mcs = method_counters();
1942   if (TieredCompilation) {
1943     MethodData* const mdo = method_data();
1944     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1945         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1946       return InvocationCounter::count_limit;
1947     } else {
1948       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1949              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1950     }
1951   } else {
1952     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1953   }
1954 }
1955 
1956 int Method::highest_comp_level() const {
1957   const MethodCounters* mcs = method_counters();
1958   if (mcs != NULL) {
1959     return mcs->highest_comp_level();
1960   } else {
1961     return CompLevel_none;
1962   }
1963 }
1964 
1965 int Method::highest_osr_comp_level() const {
1966   const MethodCounters* mcs = method_counters();
1967   if (mcs != NULL) {
1968     return mcs->highest_osr_comp_level();
1969   } else {
1970     return CompLevel_none;
1971   }
1972 }
1973 
1974 void Method::set_highest_comp_level(int level) {
1975   MethodCounters* mcs = method_counters();
1976   if (mcs != NULL) {
1977     mcs->set_highest_comp_level(level);
1978   }
1979 }
1980 
1981 void Method::set_highest_osr_comp_level(int level) {
1982   MethodCounters* mcs = method_counters();
1983   if (mcs != NULL) {
1984     mcs->set_highest_osr_comp_level(level);
1985   }
1986 }
1987 
1988 #if INCLUDE_JVMTI
1989 
1990 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1991   _bci = bci;
1992   _name_index = m->name_index();
1993   _signature_index = m->signature_index();
1994   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1995   if (_orig_bytecode == Bytecodes::_breakpoint)
1996     _orig_bytecode = m->orig_bytecode_at(_bci);
1997   _next = NULL;
1998 }
1999 
2000 void BreakpointInfo::set(Method* method) {
2001 #ifdef ASSERT
2002   {
2003     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2004     if (code == Bytecodes::_breakpoint)
2005       code = method->orig_bytecode_at(_bci);
2006     assert(orig_bytecode() == code, "original bytecode must be the same");
2007   }
2008 #endif
2009   Thread *thread = Thread::current();
2010   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2011   method->incr_number_of_breakpoints(thread);
2012   SystemDictionary::notice_modification();
2013   {
2014     // Deoptimize all dependents on this method
2015     HandleMark hm(thread);
2016     methodHandle mh(thread, method);
2017     CodeCache::flush_dependents_on_method(mh);
2018   }
2019 }
2020 
2021 void BreakpointInfo::clear(Method* method) {
2022   *method->bcp_from(_bci) = orig_bytecode();
2023   assert(method->number_of_breakpoints() > 0, "must not go negative");
2024   method->decr_number_of_breakpoints(Thread::current());
2025 }
2026 
2027 #endif // INCLUDE_JVMTI
2028 
2029 // jmethodID handling
2030 
2031 // This is a block allocating object, sort of like JNIHandleBlock, only a
2032 // lot simpler.
2033 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2034 // never get rid of it.
2035 
2036 static const int min_block_size = 8;
2037 
2038 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2039   friend class JNIMethodBlock;
2040   Method**        _methods;
2041   int             _number_of_methods;
2042   int             _top;
2043   JNIMethodBlockNode* _next;
2044 
2045  public:
2046 
2047   JNIMethodBlockNode(int num_methods = min_block_size);
2048 
2049   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2050 
2051   void ensure_methods(int num_addl_methods) {
2052     if (_top < _number_of_methods) {
2053       num_addl_methods -= _number_of_methods - _top;
2054       if (num_addl_methods <= 0) {
2055         return;
2056       }
2057     }
2058     if (_next == NULL) {
2059       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2060     } else {
2061       _next->ensure_methods(num_addl_methods);
2062     }
2063   }
2064 };
2065 
2066 class JNIMethodBlock : public CHeapObj<mtClass> {
2067   JNIMethodBlockNode _head;
2068   JNIMethodBlockNode *_last_free;
2069  public:
2070   static Method* const _free_method;
2071 
2072   JNIMethodBlock(int initial_capacity = min_block_size)
2073       : _head(initial_capacity), _last_free(&_head) {}
2074 
2075   void ensure_methods(int num_addl_methods) {
2076     _last_free->ensure_methods(num_addl_methods);
2077   }
2078 
2079   Method** add_method(Method* m) {
2080     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2081       if (b->_top < b->_number_of_methods) {
2082         // top points to the next free entry.
2083         int i = b->_top;
2084         b->_methods[i] = m;
2085         b->_top++;
2086         _last_free = b;
2087         return &(b->_methods[i]);
2088       } else if (b->_top == b->_number_of_methods) {
2089         // if the next free entry ran off the block see if there's a free entry
2090         for (int i = 0; i < b->_number_of_methods; i++) {
2091           if (b->_methods[i] == _free_method) {
2092             b->_methods[i] = m;
2093             _last_free = b;
2094             return &(b->_methods[i]);
2095           }
2096         }
2097         // Only check each block once for frees.  They're very unlikely.
2098         // Increment top past the end of the block.
2099         b->_top++;
2100       }
2101       // need to allocate a next block.
2102       if (b->_next == NULL) {
2103         b->_next = _last_free = new JNIMethodBlockNode();
2104       }
2105     }
2106     guarantee(false, "Should always allocate a free block");
2107     return NULL;
2108   }
2109 
2110   bool contains(Method** m) {
2111     if (m == NULL) return false;
2112     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2113       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2114         // This is a bit of extra checking, for two reasons.  One is
2115         // that contains() deals with pointers that are passed in by
2116         // JNI code, so making sure that the pointer is aligned
2117         // correctly is valuable.  The other is that <= and > are
2118         // technically not defined on pointers, so the if guard can
2119         // pass spuriously; no modern compiler is likely to make that
2120         // a problem, though (and if one did, the guard could also
2121         // fail spuriously, which would be bad).
2122         ptrdiff_t idx = m - b->_methods;
2123         if (b->_methods + idx == m) {
2124           return true;
2125         }
2126       }
2127     }
2128     return false;  // not found
2129   }
2130 
2131   // Doesn't really destroy it, just marks it as free so it can be reused.
2132   void destroy_method(Method** m) {
2133 #ifdef ASSERT
2134     assert(contains(m), "should be a methodID");
2135 #endif // ASSERT
2136     *m = _free_method;
2137   }
2138 
2139   // During class unloading the methods are cleared, which is different
2140   // than freed.
2141   void clear_all_methods() {
2142     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2143       for (int i = 0; i< b->_number_of_methods; i++) {
2144         b->_methods[i] = NULL;
2145       }
2146     }
2147   }
2148 #ifndef PRODUCT
2149   int count_methods() {
2150     // count all allocated methods
2151     int count = 0;
2152     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2153       for (int i = 0; i< b->_number_of_methods; i++) {
2154         if (b->_methods[i] != _free_method) count++;
2155       }
2156     }
2157     return count;
2158   }
2159 #endif // PRODUCT
2160 };
2161 
2162 // Something that can't be mistaken for an address or a markOop
2163 Method* const JNIMethodBlock::_free_method = (Method*)55;
2164 
2165 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2166   _number_of_methods = MAX2(num_methods, min_block_size);
2167   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2168   for (int i = 0; i < _number_of_methods; i++) {
2169     _methods[i] = JNIMethodBlock::_free_method;
2170   }
2171 }
2172 
2173 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2174   ClassLoaderData* cld = loader_data;
2175   if (!SafepointSynchronize::is_at_safepoint()) {
2176     // Have to add jmethod_ids() to class loader data thread-safely.
2177     // Also have to add the method to the list safely, which the cld lock
2178     // protects as well.
2179     MutexLocker ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2180     if (cld->jmethod_ids() == NULL) {
2181       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2182     } else {
2183       cld->jmethod_ids()->ensure_methods(capacity);
2184     }
2185   } else {
2186     // At safepoint, we are single threaded and can set this.
2187     if (cld->jmethod_ids() == NULL) {
2188       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2189     } else {
2190       cld->jmethod_ids()->ensure_methods(capacity);
2191     }
2192   }
2193 }
2194 
2195 // Add a method id to the jmethod_ids
2196 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2197   ClassLoaderData* cld = loader_data;
2198 
2199   if (!SafepointSynchronize::is_at_safepoint()) {
2200     // Have to add jmethod_ids() to class loader data thread-safely.
2201     // Also have to add the method to the list safely, which the cld lock
2202     // protects as well.
2203     MutexLocker ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2204     if (cld->jmethod_ids() == NULL) {
2205       cld->set_jmethod_ids(new JNIMethodBlock());
2206     }
2207     // jmethodID is a pointer to Method*
2208     return (jmethodID)cld->jmethod_ids()->add_method(m);
2209   } else {
2210     // At safepoint, we are single threaded and can set this.
2211     if (cld->jmethod_ids() == NULL) {
2212       cld->set_jmethod_ids(new JNIMethodBlock());
2213     }
2214     // jmethodID is a pointer to Method*
2215     return (jmethodID)cld->jmethod_ids()->add_method(m);
2216   }
2217 }
2218 
2219 // Mark a jmethodID as free.  This is called when there is a data race in
2220 // InstanceKlass while creating the jmethodID cache.
2221 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2222   ClassLoaderData* cld = loader_data;
2223   Method** ptr = (Method**)m;
2224   assert(cld->jmethod_ids() != NULL, "should have method handles");
2225   cld->jmethod_ids()->destroy_method(ptr);
2226 }
2227 
2228 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2229   // Can't assert the method_holder is the same because the new method has the
2230   // scratch method holder.
2231   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2232            == new_method->method_holder()->class_loader() ||
2233            new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2234          "changing to a different class loader");
2235   // Just change the method in place, jmethodID pointer doesn't change.
2236   *((Method**)jmid) = new_method;
2237 }
2238 
2239 bool Method::is_method_id(jmethodID mid) {
2240   Method* m = resolve_jmethod_id(mid);
2241   assert(m != NULL, "should be called with non-null method");
2242   InstanceKlass* ik = m->method_holder();
2243   ClassLoaderData* cld = ik->class_loader_data();
2244   if (cld->jmethod_ids() == NULL) return false;
2245   return (cld->jmethod_ids()->contains((Method**)mid));
2246 }
2247 
2248 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2249   if (mid == NULL) return NULL;
2250   Method* o = resolve_jmethod_id(mid);
2251   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2252     return NULL;
2253   }
2254   return o;
2255 };
2256 
2257 void Method::set_on_stack(const bool value) {
2258   // Set both the method itself and its constant pool.  The constant pool
2259   // on stack means some method referring to it is also on the stack.
2260   constants()->set_on_stack(value);
2261 
2262   bool already_set = on_stack();
2263   _access_flags.set_on_stack(value);
2264   if (value && !already_set) {
2265     MetadataOnStackMark::record(this);
2266   }
2267   assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2268          "emcp methods cannot run after emcp bit is cleared");
2269 }
2270 
2271 // Called when the class loader is unloaded to make all methods weak.
2272 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2273   loader_data->jmethod_ids()->clear_all_methods();
2274 }
2275 
2276 bool Method::has_method_vptr(const void* ptr) {
2277   Method m;
2278   // This assumes that the vtbl pointer is the first word of a C++ object.
2279   return dereference_vptr(&m) == dereference_vptr(ptr);
2280 }
2281 
2282 // Check that this pointer is valid by checking that the vtbl pointer matches
2283 bool Method::is_valid_method(const Method* m) {
2284   if (m == NULL) {
2285     return false;
2286   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2287     // Quick sanity check on pointer.
2288     return false;
2289   } else if (m->is_shared()) {
2290     return MetaspaceShared::is_valid_shared_method(m);
2291   } else if (Metaspace::contains_non_shared(m)) {
2292     return has_method_vptr((const void*)m);
2293   } else {
2294     return false;
2295   }
2296 }
2297 
2298 #ifndef PRODUCT
2299 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2300   out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2301 }
2302 #endif // PRODUCT
2303 
2304 
2305 // Printing
2306 
2307 #ifndef PRODUCT
2308 
2309 void Method::print_on(outputStream* st) const {
2310   ResourceMark rm;
2311   assert(is_method(), "must be method");
2312   st->print_cr("%s", internal_name());
2313   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2314   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2315   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2316   constants()->print_value_on(st); st->cr();
2317   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2318   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2319   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2320   st->print_cr(" - max stack:         %d",   max_stack());
2321   st->print_cr(" - max locals:        %d",   max_locals());
2322   st->print_cr(" - size of params:    %d",   size_of_parameters());
2323   st->print_cr(" - method size:       %d",   method_size());
2324   if (intrinsic_id() != vmIntrinsics::_none)
2325     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2326   if (highest_comp_level() != CompLevel_none)
2327     st->print_cr(" - highest level:     %d", highest_comp_level());
2328   st->print_cr(" - vtable index:      %d",   _vtable_index);
2329   if (valid_itable_index())
2330     st->print_cr(" - itable index:      %d",   itable_index());
2331   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2332   st->print(   " - adapters:          ");
2333   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2334   if (a == NULL)
2335     st->print_cr(INTPTR_FORMAT, p2i(a));
2336   else
2337     a->print_adapter_on(st);
2338   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2339   st->print_cr(" - code size:         %d",   code_size());
2340   if (code_size() != 0) {
2341     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2342     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2343   }
2344   if (method_data() != NULL) {
2345     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2346   }
2347   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2348   if (checked_exceptions_length() > 0) {
2349     CheckedExceptionElement* table = checked_exceptions_start();
2350     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2351     if (Verbose) {
2352       for (int i = 0; i < checked_exceptions_length(); i++) {
2353         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2354       }
2355     }
2356   }
2357   if (has_linenumber_table()) {
2358     u_char* table = compressed_linenumber_table();
2359     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2360     if (Verbose) {
2361       CompressedLineNumberReadStream stream(table);
2362       while (stream.read_pair()) {
2363         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2364       }
2365     }
2366   }
2367   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2368   if (localvariable_table_length() > 0) {
2369     LocalVariableTableElement* table = localvariable_table_start();
2370     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2371     if (Verbose) {
2372       for (int i = 0; i < localvariable_table_length(); i++) {
2373         int bci = table[i].start_bci;
2374         int len = table[i].length;
2375         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2376         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2377         int slot = table[i].slot;
2378         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2379       }
2380     }
2381   }
2382   if (code() != NULL) {
2383     st->print   (" - compiled code: ");
2384     code()->print_value_on(st);
2385   }
2386   if (is_native()) {
2387     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2388     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2389   }
2390 }
2391 
2392 void Method::print_linkage_flags(outputStream* st) {
2393   access_flags().print_on(st);
2394   if (is_default_method()) {
2395     st->print("default ");
2396   }
2397   if (is_overpass()) {
2398     st->print("overpass ");
2399   }
2400 }
2401 #endif //PRODUCT
2402 
2403 void Method::print_value_on(outputStream* st) const {
2404   assert(is_method(), "must be method");
2405   st->print("%s", internal_name());
2406   print_address_on(st);
2407   st->print(" ");
2408   if (WizardMode) access_flags().print_on(st);
2409   name()->print_value_on(st);
2410   st->print(" ");
2411   signature()->print_value_on(st);
2412   st->print(" in ");
2413   method_holder()->print_value_on(st);
2414   if (WizardMode) st->print("#%d", _vtable_index);
2415   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2416   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2417 }
2418 
2419 #if INCLUDE_SERVICES
2420 // Size Statistics
2421 void Method::collect_statistics(KlassSizeStats *sz) const {
2422   int mysize = sz->count(this);
2423   sz->_method_bytes += mysize;
2424   sz->_method_all_bytes += mysize;
2425   sz->_rw_bytes += mysize;
2426 
2427   if (constMethod()) {
2428     constMethod()->collect_statistics(sz);
2429   }
2430   if (method_data()) {
2431     method_data()->collect_statistics(sz);
2432   }
2433 }
2434 #endif // INCLUDE_SERVICES
2435 
2436 // LogTouchedMethods and PrintTouchedMethods
2437 
2438 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2439 // the Method may be garbage collected. Let's roll our own hash table.
2440 class TouchedMethodRecord : CHeapObj<mtTracing> {
2441 public:
2442   // It's OK to store Symbols here because they will NOT be GC'ed if
2443   // LogTouchedMethods is enabled.
2444   TouchedMethodRecord* _next;
2445   Symbol* _class_name;
2446   Symbol* _method_name;
2447   Symbol* _method_signature;
2448 };
2449 
2450 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2451 static TouchedMethodRecord** _touched_method_table = NULL;
2452 
2453 void Method::log_touched(TRAPS) {
2454 
2455   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2456   Symbol* my_class = klass_name();
2457   Symbol* my_name  = name();
2458   Symbol* my_sig   = signature();
2459 
2460   unsigned int hash = my_class->identity_hash() +
2461                       my_name->identity_hash() +
2462                       my_sig->identity_hash();
2463   juint index = juint(hash) % table_size;
2464 
2465   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2466   if (_touched_method_table == NULL) {
2467     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2468                                               mtTracing, CURRENT_PC);
2469     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2470   }
2471 
2472   TouchedMethodRecord* ptr = _touched_method_table[index];
2473   while (ptr) {
2474     if (ptr->_class_name       == my_class &&
2475         ptr->_method_name      == my_name &&
2476         ptr->_method_signature == my_sig) {
2477       return;
2478     }
2479     if (ptr->_next == NULL) break;
2480     ptr = ptr->_next;
2481   }
2482   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2483   my_class->increment_refcount();
2484   my_name->increment_refcount();
2485   my_sig->increment_refcount();
2486   nptr->_class_name         = my_class;
2487   nptr->_method_name        = my_name;
2488   nptr->_method_signature   = my_sig;
2489   nptr->_next               = NULL;
2490 
2491   if (ptr == NULL) {
2492     // first
2493     _touched_method_table[index] = nptr;
2494   } else {
2495     ptr->_next = nptr;
2496   }
2497 }
2498 
2499 void Method::print_touched_methods(outputStream* out) {
2500   MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2501   out->print_cr("# Method::print_touched_methods version 1");
2502   if (_touched_method_table) {
2503     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2504       TouchedMethodRecord* ptr = _touched_method_table[i];
2505       while(ptr) {
2506         ptr->_class_name->print_symbol_on(out);       out->print(".");
2507         ptr->_method_name->print_symbol_on(out);      out->print(":");
2508         ptr->_method_signature->print_symbol_on(out); out->cr();
2509         ptr = ptr->_next;
2510       }
2511     }
2512   }
2513 }
2514 
2515 // Verification
2516 
2517 void Method::verify_on(outputStream* st) {
2518   guarantee(is_method(), "object must be method");
2519   guarantee(constants()->is_constantPool(), "should be constant pool");
2520   MethodData* md = method_data();
2521   guarantee(md == NULL ||
2522       md->is_methodData(), "should be method data");
2523 }