1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "gc/shared/collectedHeap.inline.hpp"
  31 #include "gc/shared/gcLocker.hpp"
  32 #include "gc/shared/generation.hpp"
  33 #include "interpreter/bytecodeStream.hpp"
  34 #include "interpreter/bytecodeTracer.hpp"
  35 #include "interpreter/bytecodes.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/oopMapCache.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceClosure.hpp"
  41 #include "memory/metaspaceShared.hpp"
  42 #include "memory/oopFactory.hpp"
  43 #include "memory/resourceArea.hpp"
  44 #include "oops/constMethod.hpp"
  45 #include "oops/method.hpp"
  46 #include "oops/methodData.hpp"
  47 #include "oops/objArrayOop.inline.hpp"
  48 #include "oops/oop.inline.hpp"
  49 #include "oops/symbol.hpp"
  50 #include "prims/jvmtiExport.hpp"
  51 #include "prims/methodHandles.hpp"
  52 #include "prims/nativeLookup.hpp"
  53 #include "runtime/arguments.hpp"
  54 #include "runtime/compilationPolicy.hpp"
  55 #include "runtime/frame.inline.hpp"
  56 #include "runtime/handles.inline.hpp"
  57 #include "runtime/init.hpp"
  58 #include "runtime/orderAccess.inline.hpp"
  59 #include "runtime/relocator.hpp"
  60 #include "runtime/sharedRuntime.hpp"
  61 #include "runtime/signature.hpp"
  62 #include "utilities/align.hpp"
  63 #include "utilities/quickSort.hpp"
  64 #include "utilities/vmError.hpp"
  65 #include "utilities/xmlstream.hpp"
  66 
  67 // Implementation of Method
  68 
  69 Method* Method::allocate(ClassLoaderData* loader_data,
  70                          int byte_code_size,
  71                          AccessFlags access_flags,
  72                          InlineTableSizes* sizes,
  73                          ConstMethod::MethodType method_type,
  74                          TRAPS) {
  75   assert(!access_flags.is_native() || byte_code_size == 0,
  76          "native methods should not contain byte codes");
  77   ConstMethod* cm = ConstMethod::allocate(loader_data,
  78                                           byte_code_size,
  79                                           sizes,
  80                                           method_type,
  81                                           CHECK_NULL);
  82   int size = Method::size(access_flags.is_native());
  83   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  84 }
  85 
  86 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  87   NoSafepointVerifier no_safepoint;
  88   set_constMethod(xconst);
  89   set_access_flags(access_flags);
  90   set_intrinsic_id(vmIntrinsics::_none);
  91   set_force_inline(false);
  92   set_hidden(false);
  93   set_dont_inline(false);
  94   set_has_injected_profile(false);
  95   set_method_data(NULL);
  96   clear_method_counters();
  97   set_vtable_index(Method::garbage_vtable_index);
  98 
  99   // Fix and bury in Method*
 100   set_interpreter_entry(NULL); // sets i2i entry and from_int
 101   set_adapter_entry(NULL);
 102   clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
 103 
 104   if (access_flags.is_native()) {
 105     clear_native_function();
 106     set_signature_handler(NULL);
 107   }
 108 
 109   NOT_PRODUCT(set_compiled_invocation_count(0);)
 110 }
 111 
 112 // Release Method*.  The nmethod will be gone when we get here because
 113 // we've walked the code cache.
 114 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 115   MetadataFactory::free_metadata(loader_data, constMethod());
 116   set_constMethod(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_data());
 118   set_method_data(NULL);
 119   MetadataFactory::free_metadata(loader_data, method_counters());
 120   clear_method_counters();
 121   // The nmethod will be gone when we get here.
 122   if (code() != NULL) _code = NULL;
 123 }
 124 
 125 address Method::get_i2c_entry() {
 126   assert(adapter() != NULL, "must have");
 127   return adapter()->get_i2c_entry();
 128 }
 129 
 130 address Method::get_c2i_entry() {
 131   assert(adapter() != NULL, "must have");
 132   return adapter()->get_c2i_entry();
 133 }
 134 
 135 address Method::get_c2i_unverified_entry() {
 136   assert(adapter() != NULL, "must have");
 137   return adapter()->get_c2i_unverified_entry();
 138 }
 139 
 140 char* Method::name_and_sig_as_C_string() const {
 141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 149   const char* klass_name = klass->external_name();
 150   int klass_name_len  = (int)strlen(klass_name);
 151   int method_name_len = method_name->utf8_length();
 152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 154   strcpy(dest, klass_name);
 155   dest[klass_name_len] = '.';
 156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 158   dest[len] = 0;
 159   return dest;
 160 }
 161 
 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 163   Symbol* klass_name = klass->name();
 164   klass_name->as_klass_external_name(buf, size);
 165   int len = (int)strlen(buf);
 166 
 167   if (len < size - 1) {
 168     buf[len++] = '.';
 169 
 170     method_name->as_C_string(&(buf[len]), size - len);
 171     len = (int)strlen(buf);
 172 
 173     signature->as_C_string(&(buf[len]), size - len);
 174   }
 175 
 176   return buf;
 177 }
 178 
 179 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 181   // access exception table
 182   ExceptionTable table(mh());
 183   int length = table.length();
 184   // iterate through all entries sequentially
 185   constantPoolHandle pool(THREAD, mh->constants());
 186   for (int i = 0; i < length; i ++) {
 187     //reacquire the table in case a GC happened
 188     ExceptionTable table(mh());
 189     int beg_bci = table.start_pc(i);
 190     int end_bci = table.end_pc(i);
 191     assert(beg_bci <= end_bci, "inconsistent exception table");
 192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 193       // exception handler bci range covers throw_bci => investigate further
 194       int handler_bci = table.handler_pc(i);
 195       int klass_index = table.catch_type_index(i);
 196       if (klass_index == 0) {
 197         return handler_bci;
 198       } else if (ex_klass == NULL) {
 199         return handler_bci;
 200       } else {
 201         // we know the exception class => get the constraint class
 202         // this may require loading of the constraint class; if verification
 203         // fails or some other exception occurs, return handler_bci
 204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 205         assert(k != NULL, "klass not loaded");
 206         if (ex_klass->is_subtype_of(k)) {
 207           return handler_bci;
 208         }
 209       }
 210     }
 211   }
 212 
 213   return -1;
 214 }
 215 
 216 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 217   methodHandle h_this(Thread::current(), this);
 218   // Only GC uses the OopMapCache during thread stack root scanning
 219   // any other uses generate an oopmap but do not save it in the cache.
 220   if (Universe::heap()->is_gc_active()) {
 221     method_holder()->mask_for(h_this, bci, mask);
 222   } else {
 223     OopMapCache::compute_one_oop_map(h_this, bci, mask);
 224   }
 225   return;
 226 }
 227 
 228 
 229 int Method::bci_from(address bcp) const {
 230   if (is_native() && bcp == 0) {
 231     return 0;
 232   }
 233 #ifdef ASSERT
 234   {
 235     ResourceMark rm;
 236     if (!((is_native() && bcp == code_base()) || contains(bcp) || VMError::is_error_reported())) {
 237       tty->print("ouch!\n");
 238     }
 239     assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
 240            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 241            p2i(bcp), name_and_sig_as_C_string());
 242   }
 243 #endif
 244   return bcp - code_base();
 245 }
 246 
 247 
 248 int Method::validate_bci(int bci) const {
 249   return (bci == 0 || bci < code_size()) ? bci : -1;
 250 }
 251 
 252 // Return bci if it appears to be a valid bcp
 253 // Return -1 otherwise.
 254 // Used by profiling code, when invalid data is a possibility.
 255 // The caller is responsible for validating the Method* itself.
 256 int Method::validate_bci_from_bcp(address bcp) const {
 257   // keep bci as -1 if not a valid bci
 258   int bci = -1;
 259   if (bcp == 0 || bcp == code_base()) {
 260     // code_size() may return 0 and we allow 0 here
 261     // the method may be native
 262     bci = 0;
 263   } else if (contains(bcp)) {
 264     bci = bcp - code_base();
 265   }
 266   // Assert that if we have dodged any asserts, bci is negative.
 267   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 268   return bci;
 269 }
 270 
 271 address Method::bcp_from(int bci) const {
 272   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 273          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 274   address bcp = code_base() + bci;
 275   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 276   return bcp;
 277 }
 278 
 279 address Method::bcp_from(address bcp) const {
 280   if (is_native() && bcp == NULL) {
 281     return code_base();
 282   } else {
 283     return bcp;
 284   }
 285 }
 286 
 287 int Method::size(bool is_native) {
 288   // If native, then include pointers for native_function and signature_handler
 289   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 290   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 291   return align_metadata_size(header_size() + extra_words);
 292 }
 293 
 294 
 295 Symbol* Method::klass_name() const {
 296   return method_holder()->name();
 297 }
 298 
 299 
 300 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 301   log_trace(cds)("Iter(Method): %p", this);
 302 
 303   it->push(&_constMethod);
 304   it->push(&_method_data);
 305   it->push(&_method_counters);
 306 }
 307 
 308 // Attempt to return method oop to original state.  Clear any pointers
 309 // (to objects outside the shared spaces).  We won't be able to predict
 310 // where they should point in a new JVM.  Further initialize some
 311 // entries now in order allow them to be write protected later.
 312 
 313 void Method::remove_unshareable_info() {
 314   unlink_method();
 315 }
 316 
 317 void Method::set_vtable_index(int index) {
 318   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 319     // At runtime initialize_vtable is rerun as part of link_class_impl()
 320     // for a shared class loaded by the non-boot loader to obtain the loader
 321     // constraints based on the runtime classloaders' context.
 322     return; // don't write into the shared class
 323   } else {
 324     _vtable_index = index;
 325   }
 326 }
 327 
 328 void Method::set_itable_index(int index) {
 329   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 330     // At runtime initialize_itable is rerun as part of link_class_impl()
 331     // for a shared class loaded by the non-boot loader to obtain the loader
 332     // constraints based on the runtime classloaders' context. The dumptime
 333     // itable index should be the same as the runtime index.
 334     assert(_vtable_index == itable_index_max - index,
 335            "archived itable index is different from runtime index");
 336     return; // don’t write into the shared class
 337   } else {
 338     _vtable_index = itable_index_max - index;
 339   }
 340   assert(valid_itable_index(), "");
 341 }
 342 
 343 
 344 
 345 bool Method::was_executed_more_than(int n) {
 346   // Invocation counter is reset when the Method* is compiled.
 347   // If the method has compiled code we therefore assume it has
 348   // be excuted more than n times.
 349   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 350     // interpreter doesn't bump invocation counter of trivial methods
 351     // compiler does not bump invocation counter of compiled methods
 352     return true;
 353   }
 354   else if ((method_counters() != NULL &&
 355             method_counters()->invocation_counter()->carry()) ||
 356            (method_data() != NULL &&
 357             method_data()->invocation_counter()->carry())) {
 358     // The carry bit is set when the counter overflows and causes
 359     // a compilation to occur.  We don't know how many times
 360     // the counter has been reset, so we simply assume it has
 361     // been executed more than n times.
 362     return true;
 363   } else {
 364     return invocation_count() > n;
 365   }
 366 }
 367 
 368 void Method::print_invocation_count() {
 369   if (is_static()) tty->print("static ");
 370   if (is_final()) tty->print("final ");
 371   if (is_synchronized()) tty->print("synchronized ");
 372   if (is_native()) tty->print("native ");
 373   tty->print("%s::", method_holder()->external_name());
 374   name()->print_symbol_on(tty);
 375   signature()->print_symbol_on(tty);
 376 
 377   if (WizardMode) {
 378     // dump the size of the byte codes
 379     tty->print(" {%d}", code_size());
 380   }
 381   tty->cr();
 382 
 383   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 384   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 385   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 386 #ifndef PRODUCT
 387   if (CountCompiledCalls) {
 388     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 389   }
 390 #endif
 391 }
 392 
 393 // Build a MethodData* object to hold information about this method
 394 // collected in the interpreter.
 395 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 396   // Do not profile the method if metaspace has hit an OOM previously
 397   // allocating profiling data. Callers clear pending exception so don't
 398   // add one here.
 399   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 400     return;
 401   }
 402 
 403   // Grab a lock here to prevent multiple
 404   // MethodData*s from being created.
 405   MutexLocker ml(MethodData_lock, THREAD);
 406   if (method->method_data() == NULL) {
 407     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 408     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 409     if (HAS_PENDING_EXCEPTION) {
 410       CompileBroker::log_metaspace_failure();
 411       ClassLoaderDataGraph::set_metaspace_oom(true);
 412       return;   // return the exception (which is cleared)
 413     }
 414 
 415     method->set_method_data(method_data);
 416     if (PrintMethodData && (Verbose || WizardMode)) {
 417       ResourceMark rm(THREAD);
 418       tty->print("build_interpreter_method_data for ");
 419       method->print_name(tty);
 420       tty->cr();
 421       // At the end of the run, the MDO, full of data, will be dumped.
 422     }
 423   }
 424 }
 425 
 426 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 427   // Do not profile the method if metaspace has hit an OOM previously
 428   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 429     return NULL;
 430   }
 431 
 432   methodHandle mh(m);
 433   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 434   if (HAS_PENDING_EXCEPTION) {
 435     CompileBroker::log_metaspace_failure();
 436     ClassLoaderDataGraph::set_metaspace_oom(true);
 437     return NULL;   // return the exception (which is cleared)
 438   }
 439   if (!mh->init_method_counters(counters)) {
 440     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 441   }
 442 
 443   if (LogTouchedMethods) {
 444     mh->log_touched(CHECK_NULL);
 445   }
 446 
 447   return mh->method_counters();
 448 }
 449 
 450 void Method::cleanup_inline_caches() {
 451   // The current system doesn't use inline caches in the interpreter
 452   // => nothing to do (keep this method around for future use)
 453 }
 454 
 455 
 456 int Method::extra_stack_words() {
 457   // not an inline function, to avoid a header dependency on Interpreter
 458   return extra_stack_entries() * Interpreter::stackElementSize;
 459 }
 460 
 461 
 462 void Method::compute_size_of_parameters(Thread *thread) {
 463   ArgumentSizeComputer asc(signature());
 464   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 465 }
 466 
 467 BasicType Method::result_type() const {
 468   ResultTypeFinder rtf(signature());
 469   return rtf.type();
 470 }
 471 
 472 
 473 bool Method::is_empty_method() const {
 474   return  code_size() == 1
 475       && *code_base() == Bytecodes::_return;
 476 }
 477 
 478 
 479 bool Method::is_vanilla_constructor() const {
 480   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 481   // which only calls the superclass vanilla constructor and possibly does stores of
 482   // zero constants to local fields:
 483   //
 484   //   aload_0
 485   //   invokespecial
 486   //   indexbyte1
 487   //   indexbyte2
 488   //
 489   // followed by an (optional) sequence of:
 490   //
 491   //   aload_0
 492   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 493   //   putfield
 494   //   indexbyte1
 495   //   indexbyte2
 496   //
 497   // followed by:
 498   //
 499   //   return
 500 
 501   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 502   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 503   int size = code_size();
 504   // Check if size match
 505   if (size == 0 || size % 5 != 0) return false;
 506   address cb = code_base();
 507   int last = size - 1;
 508   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 509     // Does not call superclass default constructor
 510     return false;
 511   }
 512   // Check optional sequence
 513   for (int i = 4; i < last; i += 5) {
 514     if (cb[i] != Bytecodes::_aload_0) return false;
 515     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 516     if (cb[i+2] != Bytecodes::_putfield) return false;
 517   }
 518   return true;
 519 }
 520 
 521 
 522 bool Method::compute_has_loops_flag() {
 523   BytecodeStream bcs(this);
 524   Bytecodes::Code bc;
 525 
 526   while ((bc = bcs.next()) >= 0) {
 527     switch( bc ) {
 528       case Bytecodes::_ifeq:
 529       case Bytecodes::_ifnull:
 530       case Bytecodes::_iflt:
 531       case Bytecodes::_ifle:
 532       case Bytecodes::_ifne:
 533       case Bytecodes::_ifnonnull:
 534       case Bytecodes::_ifgt:
 535       case Bytecodes::_ifge:
 536       case Bytecodes::_if_icmpeq:
 537       case Bytecodes::_if_icmpne:
 538       case Bytecodes::_if_icmplt:
 539       case Bytecodes::_if_icmpgt:
 540       case Bytecodes::_if_icmple:
 541       case Bytecodes::_if_icmpge:
 542       case Bytecodes::_if_acmpeq:
 543       case Bytecodes::_if_acmpne:
 544       case Bytecodes::_goto:
 545       case Bytecodes::_jsr:
 546         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 547         break;
 548 
 549       case Bytecodes::_goto_w:
 550       case Bytecodes::_jsr_w:
 551         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 552         break;
 553 
 554       default:
 555         break;
 556     }
 557   }
 558   _access_flags.set_loops_flag_init();
 559   return _access_flags.has_loops();
 560 }
 561 
 562 bool Method::is_final_method(AccessFlags class_access_flags) const {
 563   // or "does_not_require_vtable_entry"
 564   // default method or overpass can occur, is not final (reuses vtable entry)
 565   // private methods in classes get vtable entries for backward class compatibility.
 566   if (is_overpass() || is_default_method())  return false;
 567   return is_final() || class_access_flags.is_final();
 568 }
 569 
 570 bool Method::is_final_method() const {
 571   return is_final_method(method_holder()->access_flags());
 572 }
 573 
 574 bool Method::is_default_method() const {
 575   if (method_holder() != NULL &&
 576       method_holder()->is_interface() &&
 577       !is_abstract() && !is_private()) {
 578     return true;
 579   } else {
 580     return false;
 581   }
 582 }
 583 
 584 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 585   if (is_final_method(class_access_flags))  return true;
 586 #ifdef ASSERT
 587   ResourceMark rm;
 588   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 589   if (class_access_flags.is_interface()) {
 590       assert(is_nonv == is_static() || is_nonv == is_private(),
 591              "nonvirtual unexpected for non-static, non-private: %s",
 592              name_and_sig_as_C_string());
 593   }
 594 #endif
 595   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 596   return vtable_index() == nonvirtual_vtable_index;
 597 }
 598 
 599 bool Method::can_be_statically_bound() const {
 600   return can_be_statically_bound(method_holder()->access_flags());
 601 }
 602 
 603 bool Method::is_accessor() const {
 604   return is_getter() || is_setter();
 605 }
 606 
 607 bool Method::is_getter() const {
 608   if (code_size() != 5) return false;
 609   if (size_of_parameters() != 1) return false;
 610   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 611   if (java_code_at(1) != Bytecodes::_getfield) return false;
 612   switch (java_code_at(4)) {
 613     case Bytecodes::_ireturn:
 614     case Bytecodes::_lreturn:
 615     case Bytecodes::_freturn:
 616     case Bytecodes::_dreturn:
 617     case Bytecodes::_areturn:
 618       break;
 619     default:
 620       return false;
 621   }
 622   return true;
 623 }
 624 
 625 bool Method::is_setter() const {
 626   if (code_size() != 6) return false;
 627   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 628   switch (java_code_at(1)) {
 629     case Bytecodes::_iload_1:
 630     case Bytecodes::_aload_1:
 631     case Bytecodes::_fload_1:
 632       if (size_of_parameters() != 2) return false;
 633       break;
 634     case Bytecodes::_dload_1:
 635     case Bytecodes::_lload_1:
 636       if (size_of_parameters() != 3) return false;
 637       break;
 638     default:
 639       return false;
 640   }
 641   if (java_code_at(2) != Bytecodes::_putfield) return false;
 642   if (java_code_at(5) != Bytecodes::_return)   return false;
 643   return true;
 644 }
 645 
 646 bool Method::is_constant_getter() const {
 647   int last_index = code_size() - 1;
 648   // Check if the first 1-3 bytecodes are a constant push
 649   // and the last bytecode is a return.
 650   return (2 <= code_size() && code_size() <= 4 &&
 651           Bytecodes::is_const(java_code_at(0)) &&
 652           Bytecodes::length_for(java_code_at(0)) == last_index &&
 653           Bytecodes::is_return(java_code_at(last_index)));
 654 }
 655 
 656 bool Method::is_initializer() const {
 657   return is_object_initializer() || is_static_initializer();
 658 }
 659 
 660 bool Method::has_valid_initializer_flags() const {
 661   return (is_static() ||
 662           method_holder()->major_version() < 51);
 663 }
 664 
 665 bool Method::is_static_initializer() const {
 666   // For classfiles version 51 or greater, ensure that the clinit method is
 667   // static.  Non-static methods with the name "<clinit>" are not static
 668   // initializers. (older classfiles exempted for backward compatibility)
 669   return name() == vmSymbols::class_initializer_name() &&
 670          has_valid_initializer_flags();
 671 }
 672 
 673 bool Method::is_object_initializer() const {
 674    return name() == vmSymbols::object_initializer_name();
 675 }
 676 
 677 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 678   int length = method->checked_exceptions_length();
 679   if (length == 0) {  // common case
 680     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 681   } else {
 682     methodHandle h_this(THREAD, method);
 683     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 684     objArrayHandle mirrors (THREAD, m_oop);
 685     for (int i = 0; i < length; i++) {
 686       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 687       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 688       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 689       mirrors->obj_at_put(i, k->java_mirror());
 690     }
 691     return mirrors;
 692   }
 693 };
 694 
 695 
 696 int Method::line_number_from_bci(int bci) const {
 697   if (bci == SynchronizationEntryBCI) bci = 0;
 698   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 699   int best_bci  =  0;
 700   int best_line = -1;
 701 
 702   if (has_linenumber_table()) {
 703     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 704     // Not necessarily sorted and not necessarily one-to-one.
 705     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 706     while (stream.read_pair()) {
 707       if (stream.bci() == bci) {
 708         // perfect match
 709         return stream.line();
 710       } else {
 711         // update best_bci/line
 712         if (stream.bci() < bci && stream.bci() >= best_bci) {
 713           best_bci  = stream.bci();
 714           best_line = stream.line();
 715         }
 716       }
 717     }
 718   }
 719   return best_line;
 720 }
 721 
 722 
 723 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 724   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 725     Thread *thread = Thread::current();
 726     Symbol* klass_name = constants()->klass_name_at(klass_index);
 727     Handle loader(thread, method_holder()->class_loader());
 728     Handle prot  (thread, method_holder()->protection_domain());
 729     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 730   } else {
 731     return true;
 732   }
 733 }
 734 
 735 
 736 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 737   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 738   if (must_be_resolved) {
 739     // Make sure klass is resolved in constantpool.
 740     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 741   }
 742   return is_klass_loaded_by_klass_index(klass_index);
 743 }
 744 
 745 
 746 void Method::set_native_function(address function, bool post_event_flag) {
 747   assert(function != NULL, "use clear_native_function to unregister natives");
 748   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 749   address* native_function = native_function_addr();
 750 
 751   // We can see racers trying to place the same native function into place. Once
 752   // is plenty.
 753   address current = *native_function;
 754   if (current == function) return;
 755   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 756       function != NULL) {
 757     // native_method_throw_unsatisfied_link_error_entry() should only
 758     // be passed when post_event_flag is false.
 759     assert(function !=
 760       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 761       "post_event_flag mis-match");
 762 
 763     // post the bind event, and possible change the bind function
 764     JvmtiExport::post_native_method_bind(this, &function);
 765   }
 766   *native_function = function;
 767   // This function can be called more than once. We must make sure that we always
 768   // use the latest registered method -> check if a stub already has been generated.
 769   // If so, we have to make it not_entrant.
 770   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 771   if (nm != NULL) {
 772     nm->make_not_entrant();
 773   }
 774 }
 775 
 776 
 777 bool Method::has_native_function() const {
 778   if (is_method_handle_intrinsic())
 779     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 780   address func = native_function();
 781   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 782 }
 783 
 784 
 785 void Method::clear_native_function() {
 786   // Note: is_method_handle_intrinsic() is allowed here.
 787   set_native_function(
 788     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 789     !native_bind_event_is_interesting);
 790   clear_code();
 791 }
 792 
 793 address Method::critical_native_function() {
 794   methodHandle mh(this);
 795   return NativeLookup::lookup_critical_entry(mh);
 796 }
 797 
 798 
 799 void Method::set_signature_handler(address handler) {
 800   address* signature_handler =  signature_handler_addr();
 801   *signature_handler = handler;
 802 }
 803 
 804 
 805 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 806   if (PrintCompilation && report) {
 807     ttyLocker ttyl;
 808     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 809     if (comp_level == CompLevel_all) {
 810       tty->print("all levels ");
 811     } else {
 812       tty->print("levels ");
 813       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 814         tty->print("%d ", i);
 815       }
 816     }
 817     this->print_short_name(tty);
 818     int size = this->code_size();
 819     if (size > 0) {
 820       tty->print(" (%d bytes)", size);
 821     }
 822     if (reason != NULL) {
 823       tty->print("   %s", reason);
 824     }
 825     tty->cr();
 826   }
 827   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 828     ttyLocker ttyl;
 829     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 830                      os::current_thread_id(), is_osr, comp_level);
 831     if (reason != NULL) {
 832       xtty->print(" reason=\'%s\'", reason);
 833     }
 834     xtty->method(this);
 835     xtty->stamp();
 836     xtty->end_elem();
 837   }
 838 }
 839 
 840 bool Method::is_always_compilable() const {
 841   // Generated adapters must be compiled
 842   if (is_method_handle_intrinsic() && is_synthetic()) {
 843     assert(!is_not_c1_compilable(), "sanity check");
 844     assert(!is_not_c2_compilable(), "sanity check");
 845     return true;
 846   }
 847 
 848   return false;
 849 }
 850 
 851 bool Method::is_not_compilable(int comp_level) const {
 852   if (number_of_breakpoints() > 0)
 853     return true;
 854   if (is_always_compilable())
 855     return false;
 856   if (comp_level == CompLevel_any)
 857     return is_not_c1_compilable() || is_not_c2_compilable();
 858   if (is_c1_compile(comp_level))
 859     return is_not_c1_compilable();
 860   if (is_c2_compile(comp_level))
 861     return is_not_c2_compilable();
 862   return false;
 863 }
 864 
 865 // call this when compiler finds that this method is not compilable
 866 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 867   if (is_always_compilable()) {
 868     // Don't mark a method which should be always compilable
 869     return;
 870   }
 871   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 872   if (comp_level == CompLevel_all) {
 873     set_not_c1_compilable();
 874     set_not_c2_compilable();
 875   } else {
 876     if (is_c1_compile(comp_level))
 877       set_not_c1_compilable();
 878     if (is_c2_compile(comp_level))
 879       set_not_c2_compilable();
 880   }
 881   CompilationPolicy::policy()->disable_compilation(this);
 882   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 883 }
 884 
 885 bool Method::is_not_osr_compilable(int comp_level) const {
 886   if (is_not_compilable(comp_level))
 887     return true;
 888   if (comp_level == CompLevel_any)
 889     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 890   if (is_c1_compile(comp_level))
 891     return is_not_c1_osr_compilable();
 892   if (is_c2_compile(comp_level))
 893     return is_not_c2_osr_compilable();
 894   return false;
 895 }
 896 
 897 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 898   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 899   if (comp_level == CompLevel_all) {
 900     set_not_c1_osr_compilable();
 901     set_not_c2_osr_compilable();
 902   } else {
 903     if (is_c1_compile(comp_level))
 904       set_not_c1_osr_compilable();
 905     if (is_c2_compile(comp_level))
 906       set_not_c2_osr_compilable();
 907   }
 908   CompilationPolicy::policy()->disable_compilation(this);
 909   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 910 }
 911 
 912 // Revert to using the interpreter and clear out the nmethod
 913 void Method::clear_code(bool acquire_lock /* = true */) {
 914   MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
 915   // this may be NULL if c2i adapters have not been made yet
 916   // Only should happen at allocate time.
 917   if (adapter() == NULL) {
 918     _from_compiled_entry    = NULL;
 919   } else {
 920     _from_compiled_entry    = adapter()->get_c2i_entry();
 921   }
 922   OrderAccess::storestore();
 923   _from_interpreted_entry = _i2i_entry;
 924   OrderAccess::storestore();
 925   _code = NULL;
 926 }
 927 
 928 #if INCLUDE_CDS
 929 // Called by class data sharing to remove any entry points (which are not shared)
 930 void Method::unlink_method() {
 931   _code = NULL;
 932 
 933   assert(DumpSharedSpaces, "dump time only");
 934   // Set the values to what they should be at run time. Note that
 935   // this Method can no longer be executed during dump time.
 936   _i2i_entry = Interpreter::entry_for_cds_method(this);
 937   _from_interpreted_entry = _i2i_entry;
 938 
 939   if (is_native()) {
 940     *native_function_addr() = NULL;
 941     set_signature_handler(NULL);
 942   }
 943   NOT_PRODUCT(set_compiled_invocation_count(0);)
 944 
 945   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 946   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 947   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 948   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 949 
 950   set_method_data(NULL);
 951   clear_method_counters();
 952 }
 953 #endif
 954 
 955 /****************************************************************************
 956 // The following illustrates how the entries work for CDS shared Methods:
 957 //
 958 // Our goal is to delay writing into a shared Method until it's compiled.
 959 // Hence, we want to determine the initial values for _i2i_entry,
 960 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
 961 //
 962 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
 963 // They also have similar signatures so that they will share the same
 964 // AdapterHandlerEntry.
 965 //
 966 // _adapter_trampoline points to a fixed location in the RW section of
 967 // the CDS archive. This location initially contains a NULL pointer. When the
 968 // first of method A or B is linked, an AdapterHandlerEntry is allocated
 969 // dynamically, and its c2i/i2c entries are generated.
 970 //
 971 // _i2i_entry and _from_interpreted_entry initially points to the same
 972 // (fixed) location in the CODE section of the CDS archive. This contains
 973 // an unconditional branch to the actual entry for "zero_locals", which is
 974 // generated at run time and may be on an arbitrary address. Thus, the
 975 // unconditional branch is also generated at run time to jump to the correct
 976 // address.
 977 //
 978 // Similarly, _from_compiled_entry points to a fixed address in the CODE
 979 // section. This address has enough space for an unconditional branch
 980 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
 981 // initialized, and the address for the actual c2i_entry is known, we emit a
 982 // branch instruction here to branch to the actual c2i_entry.
 983 //
 984 // The effect of the extra branch on the i2i and c2i entries is negligible.
 985 //
 986 // The reason for putting _adapter_trampoline in RO is many shared Methods
 987 // share the same AdapterHandlerEntry, so we can save space in the RW section
 988 // by having the extra indirection.
 989 
 990 
 991 [Method A: RW]
 992   _constMethod ----> [ConstMethod: RO]
 993                        _adapter_trampoline -----------+
 994                                                       |
 995   _i2i_entry              (same value as method B)    |
 996   _from_interpreted_entry (same value as method B)    |
 997   _from_compiled_entry    (same value as method B)    |
 998                                                       |
 999                                                       |
1000 [Method B: RW]                               +--------+
1001   _constMethod ----> [ConstMethod: RO]       |
1002                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1003                                                                                  |
1004                                                  +-------------------------------+
1005                                                  |
1006                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1007                                                               _fingerprint
1008                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1009  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1010  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1011          |                |                                                             |                 |
1012          |                |  (_cds_entry_table: CODE)                                   |                 |
1013          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1014          |                |                               (allocated at run time)       |                 |
1015          |                |  ...                           [asm code ...]               |                 |
1016          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1017          |                                                                              |                 |
1018          |                                                                              |                 |
1019          +-[compiled]-------------------------------------------------------------------+                 |
1020                                                                                                           |
1021  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1022                                     [jmp c2i_entry] ------------------------------------------------------+
1023 
1024 ***/
1025 
1026 // Called when the method_holder is getting linked. Setup entrypoints so the method
1027 // is ready to be called from interpreter, compiler, and vtables.
1028 void Method::link_method(const methodHandle& h_method, TRAPS) {
1029   // If the code cache is full, we may reenter this function for the
1030   // leftover methods that weren't linked.
1031   if (is_shared()) {
1032     address entry = Interpreter::entry_for_cds_method(h_method);
1033     assert(entry != NULL && entry == _i2i_entry,
1034            "should be correctly set during dump time");
1035     if (adapter() != NULL) {
1036       return;
1037     }
1038     assert(entry == _from_interpreted_entry,
1039            "should be correctly set during dump time");
1040   } else if (_i2i_entry != NULL) {
1041     return;
1042   }
1043   assert( _code == NULL, "nothing compiled yet" );
1044 
1045   // Setup interpreter entrypoint
1046   assert(this == h_method(), "wrong h_method()" );
1047 
1048   if (!is_shared()) {
1049     assert(adapter() == NULL, "init'd to NULL");
1050     address entry = Interpreter::entry_for_method(h_method);
1051     assert(entry != NULL, "interpreter entry must be non-null");
1052     // Sets both _i2i_entry and _from_interpreted_entry
1053     set_interpreter_entry(entry);
1054   }
1055 
1056   // Don't overwrite already registered native entries.
1057   if (is_native() && !has_native_function()) {
1058     set_native_function(
1059       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1060       !native_bind_event_is_interesting);
1061   }
1062 
1063   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1064   // special handling of vtables.  An alternative is to make adapters more
1065   // lazily by calling make_adapter() from from_compiled_entry() for the
1066   // normal calls.  For vtable calls life gets more complicated.  When a
1067   // call-site goes mega-morphic we need adapters in all methods which can be
1068   // called from the vtable.  We need adapters on such methods that get loaded
1069   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1070   // problem we'll make these lazily later.
1071   (void) make_adapters(h_method, CHECK);
1072 
1073   // ONLY USE the h_method now as make_adapter may have blocked
1074 
1075 }
1076 
1077 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1078   // Adapters for compiled code are made eagerly here.  They are fairly
1079   // small (generally < 100 bytes) and quick to make (and cached and shared)
1080   // so making them eagerly shouldn't be too expensive.
1081   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1082   if (adapter == NULL ) {
1083     if (!is_init_completed()) {
1084       // Don't throw exceptions during VM initialization because java.lang.* classes
1085       // might not have been initialized, causing problems when constructing the
1086       // Java exception object.
1087       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1088     } else {
1089       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1090     }
1091   }
1092 
1093   if (mh->is_shared()) {
1094     assert(mh->adapter() == adapter, "must be");
1095     assert(mh->_from_compiled_entry != NULL, "must be");
1096   } else {
1097     mh->set_adapter_entry(adapter);
1098     mh->_from_compiled_entry = adapter->get_c2i_entry();
1099   }
1100   return adapter->get_c2i_entry();
1101 }
1102 
1103 void Method::restore_unshareable_info(TRAPS) {
1104   assert(is_method() && is_valid_method(), "ensure C++ vtable is restored");
1105 
1106   // Since restore_unshareable_info can be called more than once for a method, don't
1107   // redo any work.
1108   if (adapter() == NULL) {
1109     methodHandle mh(THREAD, this);
1110     link_method(mh, CHECK);
1111   }
1112 }
1113 
1114 volatile address Method::from_compiled_entry_no_trampoline() const {
1115   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1116   if (code) {
1117     return code->verified_entry_point();
1118   } else {
1119     return adapter()->get_c2i_entry();
1120   }
1121 }
1122 
1123 // The verified_code_entry() must be called when a invoke is resolved
1124 // on this method.
1125 
1126 // It returns the compiled code entry point, after asserting not null.
1127 // This function is called after potential safepoints so that nmethod
1128 // or adapter that it points to is still live and valid.
1129 // This function must not hit a safepoint!
1130 address Method::verified_code_entry() {
1131   debug_only(NoSafepointVerifier nsv;)
1132   assert(_from_compiled_entry != NULL, "must be set");
1133   return _from_compiled_entry;
1134 }
1135 
1136 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1137 // (could be racing a deopt).
1138 // Not inline to avoid circular ref.
1139 bool Method::check_code() const {
1140   // cached in a register or local.  There's a race on the value of the field.
1141   CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1142   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1143 }
1144 
1145 // Install compiled code.  Instantly it can execute.
1146 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1147   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1148   assert( code, "use clear_code to remove code" );
1149   assert( mh->check_code(), "" );
1150 
1151   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1152 
1153   // These writes must happen in this order, because the interpreter will
1154   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1155   // which jumps to _from_compiled_entry.
1156   mh->_code = code;             // Assign before allowing compiled code to exec
1157 
1158   int comp_level = code->comp_level();
1159   // In theory there could be a race here. In practice it is unlikely
1160   // and not worth worrying about.
1161   if (comp_level > mh->highest_comp_level()) {
1162     mh->set_highest_comp_level(comp_level);
1163   }
1164 
1165   OrderAccess::storestore();
1166 #ifdef SHARK
1167   mh->_from_interpreted_entry = code->insts_begin();
1168 #else //!SHARK
1169   mh->_from_compiled_entry = code->verified_entry_point();
1170   OrderAccess::storestore();
1171   // Instantly compiled code can execute.
1172   if (!mh->is_method_handle_intrinsic())
1173     mh->_from_interpreted_entry = mh->get_i2c_entry();
1174 #endif //!SHARK
1175 }
1176 
1177 
1178 bool Method::is_overridden_in(Klass* k) const {
1179   InstanceKlass* ik = InstanceKlass::cast(k);
1180 
1181   if (ik->is_interface()) return false;
1182 
1183   // If method is an interface, we skip it - except if it
1184   // is a miranda method
1185   if (method_holder()->is_interface()) {
1186     // Check that method is not a miranda method
1187     if (ik->lookup_method(name(), signature()) == NULL) {
1188       // No implementation exist - so miranda method
1189       return false;
1190     }
1191     return true;
1192   }
1193 
1194   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1195   if (!has_vtable_index()) {
1196     return false;
1197   } else {
1198     Method* vt_m = ik->method_at_vtable(vtable_index());
1199     return vt_m != this;
1200   }
1201 }
1202 
1203 
1204 // give advice about whether this Method* should be cached or not
1205 bool Method::should_not_be_cached() const {
1206   if (is_old()) {
1207     // This method has been redefined. It is either EMCP or obsolete
1208     // and we don't want to cache it because that would pin the method
1209     // down and prevent it from being collectible if and when it
1210     // finishes executing.
1211     return true;
1212   }
1213 
1214   // caching this method should be just fine
1215   return false;
1216 }
1217 
1218 
1219 /**
1220  *  Returns true if this is one of the specially treated methods for
1221  *  security related stack walks (like Reflection.getCallerClass).
1222  */
1223 bool Method::is_ignored_by_security_stack_walk() const {
1224   if (intrinsic_id() == vmIntrinsics::_invoke) {
1225     // This is Method.invoke() -- ignore it
1226     return true;
1227   }
1228   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1229     // This is an auxilary frame -- ignore it
1230     return true;
1231   }
1232   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1233     // This is an internal adapter frame for method handles -- ignore it
1234     return true;
1235   }
1236   return false;
1237 }
1238 
1239 
1240 // Constant pool structure for invoke methods:
1241 enum {
1242   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1243   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1244   _imcp_limit
1245 };
1246 
1247 // Test if this method is an MH adapter frame generated by Java code.
1248 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1249 bool Method::is_compiled_lambda_form() const {
1250   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1251 }
1252 
1253 // Test if this method is an internal MH primitive method.
1254 bool Method::is_method_handle_intrinsic() const {
1255   vmIntrinsics::ID iid = intrinsic_id();
1256   return (MethodHandles::is_signature_polymorphic(iid) &&
1257           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1258 }
1259 
1260 bool Method::has_member_arg() const {
1261   vmIntrinsics::ID iid = intrinsic_id();
1262   return (MethodHandles::is_signature_polymorphic(iid) &&
1263           MethodHandles::has_member_arg(iid));
1264 }
1265 
1266 // Make an instance of a signature-polymorphic internal MH primitive.
1267 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1268                                                          Symbol* signature,
1269                                                          TRAPS) {
1270   ResourceMark rm;
1271   methodHandle empty;
1272 
1273   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1274   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1275   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1276   if (TraceMethodHandles) {
1277     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1278   }
1279 
1280   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1281   name->increment_refcount();
1282   signature->increment_refcount();
1283 
1284   int cp_length = _imcp_limit;
1285   ClassLoaderData* loader_data = holder->class_loader_data();
1286   constantPoolHandle cp;
1287   {
1288     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1289     cp = constantPoolHandle(THREAD, cp_oop);
1290   }
1291   cp->set_pool_holder(holder);
1292   cp->symbol_at_put(_imcp_invoke_name,       name);
1293   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1294   cp->set_has_preresolution();
1295 
1296   // decide on access bits:  public or not?
1297   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1298   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1299   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1300   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1301 
1302   methodHandle m;
1303   {
1304     InlineTableSizes sizes;
1305     Method* m_oop = Method::allocate(loader_data, 0,
1306                                      accessFlags_from(flags_bits), &sizes,
1307                                      ConstMethod::NORMAL, CHECK_(empty));
1308     m = methodHandle(THREAD, m_oop);
1309   }
1310   m->set_constants(cp());
1311   m->set_name_index(_imcp_invoke_name);
1312   m->set_signature_index(_imcp_invoke_signature);
1313   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1314   assert(m->signature() == signature, "");
1315   ResultTypeFinder rtf(signature);
1316   m->constMethod()->set_result_type(rtf.type());
1317   m->compute_size_of_parameters(THREAD);
1318   m->init_intrinsic_id();
1319   assert(m->is_method_handle_intrinsic(), "");
1320 #ifdef ASSERT
1321   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1322   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1323   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1324 #endif //ASSERT
1325 
1326   // Finally, set up its entry points.
1327   assert(m->can_be_statically_bound(), "");
1328   m->set_vtable_index(Method::nonvirtual_vtable_index);
1329   m->link_method(m, CHECK_(empty));
1330 
1331   if (TraceMethodHandles && (Verbose || WizardMode)) {
1332     ttyLocker ttyl;
1333     m->print_on(tty);
1334   }
1335 
1336   return m;
1337 }
1338 
1339 Klass* Method::check_non_bcp_klass(Klass* klass) {
1340   if (klass != NULL && klass->class_loader() != NULL) {
1341     if (klass->is_objArray_klass())
1342       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1343     return klass;
1344   }
1345   return NULL;
1346 }
1347 
1348 
1349 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1350                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1351   // Code below does not work for native methods - they should never get rewritten anyway
1352   assert(!m->is_native(), "cannot rewrite native methods");
1353   // Allocate new Method*
1354   AccessFlags flags = m->access_flags();
1355 
1356   ConstMethod* cm = m->constMethod();
1357   int checked_exceptions_len = cm->checked_exceptions_length();
1358   int localvariable_len = cm->localvariable_table_length();
1359   int exception_table_len = cm->exception_table_length();
1360   int method_parameters_len = cm->method_parameters_length();
1361   int method_annotations_len = cm->method_annotations_length();
1362   int parameter_annotations_len = cm->parameter_annotations_length();
1363   int type_annotations_len = cm->type_annotations_length();
1364   int default_annotations_len = cm->default_annotations_length();
1365 
1366   InlineTableSizes sizes(
1367       localvariable_len,
1368       new_compressed_linenumber_size,
1369       exception_table_len,
1370       checked_exceptions_len,
1371       method_parameters_len,
1372       cm->generic_signature_index(),
1373       method_annotations_len,
1374       parameter_annotations_len,
1375       type_annotations_len,
1376       default_annotations_len,
1377       0);
1378 
1379   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1380   Method* newm_oop = Method::allocate(loader_data,
1381                                       new_code_length,
1382                                       flags,
1383                                       &sizes,
1384                                       m->method_type(),
1385                                       CHECK_(methodHandle()));
1386   methodHandle newm (THREAD, newm_oop);
1387 
1388   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1389   ConstMethod* newcm = newm->constMethod();
1390   int new_const_method_size = newm->constMethod()->size();
1391 
1392   // This works because the source and target are both Methods. Some compilers
1393   // (e.g., clang) complain that the target vtable pointer will be stomped,
1394   // so cast away newm()'s and m()'s Methodness.
1395   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1396 
1397   // Create shallow copy of ConstMethod.
1398   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1399 
1400   // Reset correct method/const method, method size, and parameter info
1401   newm->set_constMethod(newcm);
1402   newm->constMethod()->set_code_size(new_code_length);
1403   newm->constMethod()->set_constMethod_size(new_const_method_size);
1404   assert(newm->code_size() == new_code_length, "check");
1405   assert(newm->method_parameters_length() == method_parameters_len, "check");
1406   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1407   assert(newm->exception_table_length() == exception_table_len, "check");
1408   assert(newm->localvariable_table_length() == localvariable_len, "check");
1409   // Copy new byte codes
1410   memcpy(newm->code_base(), new_code, new_code_length);
1411   // Copy line number table
1412   if (new_compressed_linenumber_size > 0) {
1413     memcpy(newm->compressed_linenumber_table(),
1414            new_compressed_linenumber_table,
1415            new_compressed_linenumber_size);
1416   }
1417   // Copy method_parameters
1418   if (method_parameters_len > 0) {
1419     memcpy(newm->method_parameters_start(),
1420            m->method_parameters_start(),
1421            method_parameters_len * sizeof(MethodParametersElement));
1422   }
1423   // Copy checked_exceptions
1424   if (checked_exceptions_len > 0) {
1425     memcpy(newm->checked_exceptions_start(),
1426            m->checked_exceptions_start(),
1427            checked_exceptions_len * sizeof(CheckedExceptionElement));
1428   }
1429   // Copy exception table
1430   if (exception_table_len > 0) {
1431     memcpy(newm->exception_table_start(),
1432            m->exception_table_start(),
1433            exception_table_len * sizeof(ExceptionTableElement));
1434   }
1435   // Copy local variable number table
1436   if (localvariable_len > 0) {
1437     memcpy(newm->localvariable_table_start(),
1438            m->localvariable_table_start(),
1439            localvariable_len * sizeof(LocalVariableTableElement));
1440   }
1441   // Copy stackmap table
1442   if (m->has_stackmap_table()) {
1443     int code_attribute_length = m->stackmap_data()->length();
1444     Array<u1>* stackmap_data =
1445       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1446     memcpy((void*)stackmap_data->adr_at(0),
1447            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1448     newm->set_stackmap_data(stackmap_data);
1449   }
1450 
1451   // copy annotations over to new method
1452   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1453   return newm;
1454 }
1455 
1456 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1457   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1458   // because we are not loading from core libraries
1459   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1460   // which does not use the class default class loader so we check for its loader here
1461   const InstanceKlass* ik = InstanceKlass::cast(holder);
1462   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1463     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1464   }
1465 
1466   // see if the klass name is well-known:
1467   Symbol* klass_name = ik->name();
1468   return vmSymbols::find_sid(klass_name);
1469 }
1470 
1471 void Method::init_intrinsic_id() {
1472   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1473   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1474   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1475   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1476 
1477   // the klass name is well-known:
1478   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1479   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1480 
1481   // ditto for method and signature:
1482   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1483   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1484       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1485       && name_id == vmSymbols::NO_SID) {
1486     return;
1487   }
1488   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1489   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1490       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1491       && sig_id == vmSymbols::NO_SID) {
1492     return;
1493   }
1494   jshort flags = access_flags().as_short();
1495 
1496   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1497   if (id != vmIntrinsics::_none) {
1498     set_intrinsic_id(id);
1499     if (id == vmIntrinsics::_Class_cast) {
1500       // Even if the intrinsic is rejected, we want to inline this simple method.
1501       set_force_inline(true);
1502     }
1503     return;
1504   }
1505 
1506   // A few slightly irregular cases:
1507   switch (klass_id) {
1508   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1509     // Second chance: check in regular Math.
1510     switch (name_id) {
1511     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1512     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1513     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1514       // pretend it is the corresponding method in the non-strict class:
1515       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1516       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1517       break;
1518     default:
1519       break;
1520     }
1521     break;
1522 
1523   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1524   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1525   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1526     if (!is_native())  break;
1527     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1528     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1529       id = vmIntrinsics::_none;
1530     break;
1531 
1532   default:
1533     break;
1534   }
1535 
1536   if (id != vmIntrinsics::_none) {
1537     // Set up its iid.  It is an alias method.
1538     set_intrinsic_id(id);
1539     return;
1540   }
1541 }
1542 
1543 // These two methods are static since a GC may move the Method
1544 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1545   if (!THREAD->can_call_java()) {
1546     // There is nothing useful this routine can do from within the Compile thread.
1547     // Hopefully, the signature contains only well-known classes.
1548     // We could scan for this and return true/false, but the caller won't care.
1549     return false;
1550   }
1551   bool sig_is_loaded = true;
1552   Handle class_loader(THREAD, m->method_holder()->class_loader());
1553   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1554   ResourceMark rm(THREAD);
1555   Symbol*  signature = m->signature();
1556   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1557     if (ss.is_object()) {
1558       Symbol* sym = ss.as_symbol(CHECK_(false));
1559       Symbol*  name  = sym;
1560       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1561                                              protection_domain, THREAD);
1562       // We are loading classes eagerly. If a ClassNotFoundException or
1563       // a LinkageError was generated, be sure to ignore it.
1564       if (HAS_PENDING_EXCEPTION) {
1565         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1566             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1567           CLEAR_PENDING_EXCEPTION;
1568         } else {
1569           return false;
1570         }
1571       }
1572       if( klass == NULL) { sig_is_loaded = false; }
1573     }
1574   }
1575   return sig_is_loaded;
1576 }
1577 
1578 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1579   Handle class_loader(THREAD, m->method_holder()->class_loader());
1580   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1581   ResourceMark rm(THREAD);
1582   Symbol*  signature = m->signature();
1583   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1584     if (ss.type() == T_OBJECT) {
1585       Symbol* name = ss.as_symbol_or_null();
1586       if (name == NULL) return true;
1587       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1588       if (klass == NULL) return true;
1589     }
1590   }
1591   return false;
1592 }
1593 
1594 // Exposed so field engineers can debug VM
1595 void Method::print_short_name(outputStream* st) {
1596   ResourceMark rm;
1597 #ifdef PRODUCT
1598   st->print(" %s::", method_holder()->external_name());
1599 #else
1600   st->print(" %s::", method_holder()->internal_name());
1601 #endif
1602   name()->print_symbol_on(st);
1603   if (WizardMode) signature()->print_symbol_on(st);
1604   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1605     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1606 }
1607 
1608 // Comparer for sorting an object array containing
1609 // Method*s.
1610 static int method_comparator(Method* a, Method* b) {
1611   return a->name()->fast_compare(b->name());
1612 }
1613 
1614 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1615 // default_methods also uses this without the ordering for fast find_method
1616 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1617   int length = methods->length();
1618   if (length > 1) {
1619     {
1620       NoSafepointVerifier nsv;
1621       QuickSort::sort(methods->data(), length, method_comparator, idempotent);
1622     }
1623     // Reset method ordering
1624     if (set_idnums) {
1625       for (int i = 0; i < length; i++) {
1626         Method* m = methods->at(i);
1627         m->set_method_idnum(i);
1628         m->set_orig_method_idnum(i);
1629       }
1630     }
1631   }
1632 }
1633 
1634 //-----------------------------------------------------------------------------------
1635 // Non-product code unless JVM/TI needs it
1636 
1637 #if !defined(PRODUCT) || INCLUDE_JVMTI
1638 class SignatureTypePrinter : public SignatureTypeNames {
1639  private:
1640   outputStream* _st;
1641   bool _use_separator;
1642 
1643   void type_name(const char* name) {
1644     if (_use_separator) _st->print(", ");
1645     _st->print("%s", name);
1646     _use_separator = true;
1647   }
1648 
1649  public:
1650   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1651     _st = st;
1652     _use_separator = false;
1653   }
1654 
1655   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1656   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1657 };
1658 
1659 
1660 void Method::print_name(outputStream* st) {
1661   Thread *thread = Thread::current();
1662   ResourceMark rm(thread);
1663   st->print("%s ", is_static() ? "static" : "virtual");
1664   if (WizardMode) {
1665     st->print("%s.", method_holder()->internal_name());
1666     name()->print_symbol_on(st);
1667     signature()->print_symbol_on(st);
1668   } else {
1669     SignatureTypePrinter sig(signature(), st);
1670     sig.print_returntype();
1671     st->print(" %s.", method_holder()->internal_name());
1672     name()->print_symbol_on(st);
1673     st->print("(");
1674     sig.print_parameters();
1675     st->print(")");
1676   }
1677 }
1678 #endif // !PRODUCT || INCLUDE_JVMTI
1679 
1680 
1681 void Method::print_codes_on(outputStream* st) const {
1682   print_codes_on(0, code_size(), st);
1683 }
1684 
1685 void Method::print_codes_on(int from, int to, outputStream* st) const {
1686   Thread *thread = Thread::current();
1687   ResourceMark rm(thread);
1688   methodHandle mh (thread, (Method*)this);
1689   BytecodeStream s(mh);
1690   s.set_interval(from, to);
1691   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1692   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1693 }
1694 
1695 
1696 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1697 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1698 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1699 // as end-of-stream terminator.
1700 
1701 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1702   // bci and line number does not compress into single byte.
1703   // Write out escape character and use regular compression for bci and line number.
1704   write_byte((jubyte)0xFF);
1705   write_signed_int(bci_delta);
1706   write_signed_int(line_delta);
1707 }
1708 
1709 // See comment in method.hpp which explains why this exists.
1710 #if defined(_M_AMD64) && _MSC_VER >= 1400
1711 #pragma optimize("", off)
1712 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1713   write_pair_inline(bci, line);
1714 }
1715 #pragma optimize("", on)
1716 #endif
1717 
1718 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1719   _bci = 0;
1720   _line = 0;
1721 };
1722 
1723 
1724 bool CompressedLineNumberReadStream::read_pair() {
1725   jubyte next = read_byte();
1726   // Check for terminator
1727   if (next == 0) return false;
1728   if (next == 0xFF) {
1729     // Escape character, regular compression used
1730     _bci  += read_signed_int();
1731     _line += read_signed_int();
1732   } else {
1733     // Single byte compression used
1734     _bci  += next >> 3;
1735     _line += next & 0x7;
1736   }
1737   return true;
1738 }
1739 
1740 #if INCLUDE_JVMTI
1741 
1742 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1743   BreakpointInfo* bp = method_holder()->breakpoints();
1744   for (; bp != NULL; bp = bp->next()) {
1745     if (bp->match(this, bci)) {
1746       return bp->orig_bytecode();
1747     }
1748   }
1749   {
1750     ResourceMark rm;
1751     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1752   }
1753   return Bytecodes::_shouldnotreachhere;
1754 }
1755 
1756 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1757   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1758   BreakpointInfo* bp = method_holder()->breakpoints();
1759   for (; bp != NULL; bp = bp->next()) {
1760     if (bp->match(this, bci)) {
1761       bp->set_orig_bytecode(code);
1762       // and continue, in case there is more than one
1763     }
1764   }
1765 }
1766 
1767 void Method::set_breakpoint(int bci) {
1768   InstanceKlass* ik = method_holder();
1769   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1770   bp->set_next(ik->breakpoints());
1771   ik->set_breakpoints(bp);
1772   // do this last:
1773   bp->set(this);
1774 }
1775 
1776 static void clear_matches(Method* m, int bci) {
1777   InstanceKlass* ik = m->method_holder();
1778   BreakpointInfo* prev_bp = NULL;
1779   BreakpointInfo* next_bp;
1780   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1781     next_bp = bp->next();
1782     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1783     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1784       // do this first:
1785       bp->clear(m);
1786       // unhook it
1787       if (prev_bp != NULL)
1788         prev_bp->set_next(next_bp);
1789       else
1790         ik->set_breakpoints(next_bp);
1791       delete bp;
1792       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1793       // at same location. So we have multiple matching (method_index and bci)
1794       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1795       // breakpoint for clear_breakpoint request and keep all other method versions
1796       // BreakpointInfo for future clear_breakpoint request.
1797       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1798       // which is being called when class is unloaded. We delete all the Breakpoint
1799       // information for all versions of method. We may not correctly restore the original
1800       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1801       // so these methods won't be used anymore.
1802       if (bci >= 0) {
1803         break;
1804       }
1805     } else {
1806       // This one is a keeper.
1807       prev_bp = bp;
1808     }
1809   }
1810 }
1811 
1812 void Method::clear_breakpoint(int bci) {
1813   assert(bci >= 0, "");
1814   clear_matches(this, bci);
1815 }
1816 
1817 void Method::clear_all_breakpoints() {
1818   clear_matches(this, -1);
1819 }
1820 
1821 #endif // INCLUDE_JVMTI
1822 
1823 int Method::invocation_count() {
1824   MethodCounters *mcs = method_counters();
1825   if (TieredCompilation) {
1826     MethodData* const mdo = method_data();
1827     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1828         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1829       return InvocationCounter::count_limit;
1830     } else {
1831       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1832              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1833     }
1834   } else {
1835     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1836   }
1837 }
1838 
1839 int Method::backedge_count() {
1840   MethodCounters *mcs = method_counters();
1841   if (TieredCompilation) {
1842     MethodData* const mdo = method_data();
1843     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1844         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1845       return InvocationCounter::count_limit;
1846     } else {
1847       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1848              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1849     }
1850   } else {
1851     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1852   }
1853 }
1854 
1855 int Method::highest_comp_level() const {
1856   const MethodCounters* mcs = method_counters();
1857   if (mcs != NULL) {
1858     return mcs->highest_comp_level();
1859   } else {
1860     return CompLevel_none;
1861   }
1862 }
1863 
1864 int Method::highest_osr_comp_level() const {
1865   const MethodCounters* mcs = method_counters();
1866   if (mcs != NULL) {
1867     return mcs->highest_osr_comp_level();
1868   } else {
1869     return CompLevel_none;
1870   }
1871 }
1872 
1873 void Method::set_highest_comp_level(int level) {
1874   MethodCounters* mcs = method_counters();
1875   if (mcs != NULL) {
1876     mcs->set_highest_comp_level(level);
1877   }
1878 }
1879 
1880 void Method::set_highest_osr_comp_level(int level) {
1881   MethodCounters* mcs = method_counters();
1882   if (mcs != NULL) {
1883     mcs->set_highest_osr_comp_level(level);
1884   }
1885 }
1886 
1887 #if INCLUDE_JVMTI
1888 
1889 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1890   _bci = bci;
1891   _name_index = m->name_index();
1892   _signature_index = m->signature_index();
1893   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1894   if (_orig_bytecode == Bytecodes::_breakpoint)
1895     _orig_bytecode = m->orig_bytecode_at(_bci);
1896   _next = NULL;
1897 }
1898 
1899 void BreakpointInfo::set(Method* method) {
1900 #ifdef ASSERT
1901   {
1902     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1903     if (code == Bytecodes::_breakpoint)
1904       code = method->orig_bytecode_at(_bci);
1905     assert(orig_bytecode() == code, "original bytecode must be the same");
1906   }
1907 #endif
1908   Thread *thread = Thread::current();
1909   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1910   method->incr_number_of_breakpoints(thread);
1911   SystemDictionary::notice_modification();
1912   {
1913     // Deoptimize all dependents on this method
1914     HandleMark hm(thread);
1915     methodHandle mh(thread, method);
1916     CodeCache::flush_dependents_on_method(mh);
1917   }
1918 }
1919 
1920 void BreakpointInfo::clear(Method* method) {
1921   *method->bcp_from(_bci) = orig_bytecode();
1922   assert(method->number_of_breakpoints() > 0, "must not go negative");
1923   method->decr_number_of_breakpoints(Thread::current());
1924 }
1925 
1926 #endif // INCLUDE_JVMTI
1927 
1928 // jmethodID handling
1929 
1930 // This is a block allocating object, sort of like JNIHandleBlock, only a
1931 // lot simpler.
1932 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1933 // never get rid of it.
1934 
1935 static const int min_block_size = 8;
1936 
1937 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1938   friend class JNIMethodBlock;
1939   Method**        _methods;
1940   int             _number_of_methods;
1941   int             _top;
1942   JNIMethodBlockNode* _next;
1943 
1944  public:
1945 
1946   JNIMethodBlockNode(int num_methods = min_block_size);
1947 
1948   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1949 
1950   void ensure_methods(int num_addl_methods) {
1951     if (_top < _number_of_methods) {
1952       num_addl_methods -= _number_of_methods - _top;
1953       if (num_addl_methods <= 0) {
1954         return;
1955       }
1956     }
1957     if (_next == NULL) {
1958       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1959     } else {
1960       _next->ensure_methods(num_addl_methods);
1961     }
1962   }
1963 };
1964 
1965 class JNIMethodBlock : public CHeapObj<mtClass> {
1966   JNIMethodBlockNode _head;
1967   JNIMethodBlockNode *_last_free;
1968  public:
1969   static Method* const _free_method;
1970 
1971   JNIMethodBlock(int initial_capacity = min_block_size)
1972       : _head(initial_capacity), _last_free(&_head) {}
1973 
1974   void ensure_methods(int num_addl_methods) {
1975     _last_free->ensure_methods(num_addl_methods);
1976   }
1977 
1978   Method** add_method(Method* m) {
1979     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1980       if (b->_top < b->_number_of_methods) {
1981         // top points to the next free entry.
1982         int i = b->_top;
1983         b->_methods[i] = m;
1984         b->_top++;
1985         _last_free = b;
1986         return &(b->_methods[i]);
1987       } else if (b->_top == b->_number_of_methods) {
1988         // if the next free entry ran off the block see if there's a free entry
1989         for (int i = 0; i < b->_number_of_methods; i++) {
1990           if (b->_methods[i] == _free_method) {
1991             b->_methods[i] = m;
1992             _last_free = b;
1993             return &(b->_methods[i]);
1994           }
1995         }
1996         // Only check each block once for frees.  They're very unlikely.
1997         // Increment top past the end of the block.
1998         b->_top++;
1999       }
2000       // need to allocate a next block.
2001       if (b->_next == NULL) {
2002         b->_next = _last_free = new JNIMethodBlockNode();
2003       }
2004     }
2005     guarantee(false, "Should always allocate a free block");
2006     return NULL;
2007   }
2008 
2009   bool contains(Method** m) {
2010     if (m == NULL) return false;
2011     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2012       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2013         // This is a bit of extra checking, for two reasons.  One is
2014         // that contains() deals with pointers that are passed in by
2015         // JNI code, so making sure that the pointer is aligned
2016         // correctly is valuable.  The other is that <= and > are
2017         // technically not defined on pointers, so the if guard can
2018         // pass spuriously; no modern compiler is likely to make that
2019         // a problem, though (and if one did, the guard could also
2020         // fail spuriously, which would be bad).
2021         ptrdiff_t idx = m - b->_methods;
2022         if (b->_methods + idx == m) {
2023           return true;
2024         }
2025       }
2026     }
2027     return false;  // not found
2028   }
2029 
2030   // Doesn't really destroy it, just marks it as free so it can be reused.
2031   void destroy_method(Method** m) {
2032 #ifdef ASSERT
2033     assert(contains(m), "should be a methodID");
2034 #endif // ASSERT
2035     *m = _free_method;
2036   }
2037 
2038   // During class unloading the methods are cleared, which is different
2039   // than freed.
2040   void clear_all_methods() {
2041     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2042       for (int i = 0; i< b->_number_of_methods; i++) {
2043         b->_methods[i] = NULL;
2044       }
2045     }
2046   }
2047 #ifndef PRODUCT
2048   int count_methods() {
2049     // count all allocated methods
2050     int count = 0;
2051     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2052       for (int i = 0; i< b->_number_of_methods; i++) {
2053         if (b->_methods[i] != _free_method) count++;
2054       }
2055     }
2056     return count;
2057   }
2058 #endif // PRODUCT
2059 };
2060 
2061 // Something that can't be mistaken for an address or a markOop
2062 Method* const JNIMethodBlock::_free_method = (Method*)55;
2063 
2064 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
2065   _number_of_methods = MAX2(num_methods, min_block_size);
2066   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2067   for (int i = 0; i < _number_of_methods; i++) {
2068     _methods[i] = JNIMethodBlock::_free_method;
2069   }
2070 }
2071 
2072 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2073   ClassLoaderData* cld = loader_data;
2074   if (!SafepointSynchronize::is_at_safepoint()) {
2075     // Have to add jmethod_ids() to class loader data thread-safely.
2076     // Also have to add the method to the list safely, which the cld lock
2077     // protects as well.
2078     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2079     if (cld->jmethod_ids() == NULL) {
2080       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2081     } else {
2082       cld->jmethod_ids()->ensure_methods(capacity);
2083     }
2084   } else {
2085     // At safepoint, we are single threaded and can set this.
2086     if (cld->jmethod_ids() == NULL) {
2087       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2088     } else {
2089       cld->jmethod_ids()->ensure_methods(capacity);
2090     }
2091   }
2092 }
2093 
2094 // Add a method id to the jmethod_ids
2095 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2096   ClassLoaderData* cld = loader_data;
2097 
2098   if (!SafepointSynchronize::is_at_safepoint()) {
2099     // Have to add jmethod_ids() to class loader data thread-safely.
2100     // Also have to add the method to the list safely, which the cld lock
2101     // protects as well.
2102     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2103     if (cld->jmethod_ids() == NULL) {
2104       cld->set_jmethod_ids(new JNIMethodBlock());
2105     }
2106     // jmethodID is a pointer to Method*
2107     return (jmethodID)cld->jmethod_ids()->add_method(m);
2108   } else {
2109     // At safepoint, we are single threaded and can set this.
2110     if (cld->jmethod_ids() == NULL) {
2111       cld->set_jmethod_ids(new JNIMethodBlock());
2112     }
2113     // jmethodID is a pointer to Method*
2114     return (jmethodID)cld->jmethod_ids()->add_method(m);
2115   }
2116 }
2117 
2118 // Mark a jmethodID as free.  This is called when there is a data race in
2119 // InstanceKlass while creating the jmethodID cache.
2120 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2121   ClassLoaderData* cld = loader_data;
2122   Method** ptr = (Method**)m;
2123   assert(cld->jmethod_ids() != NULL, "should have method handles");
2124   cld->jmethod_ids()->destroy_method(ptr);
2125 }
2126 
2127 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2128   // Can't assert the method_holder is the same because the new method has the
2129   // scratch method holder.
2130   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2131            == new_method->method_holder()->class_loader(),
2132          "changing to a different class loader");
2133   // Just change the method in place, jmethodID pointer doesn't change.
2134   *((Method**)jmid) = new_method;
2135 }
2136 
2137 bool Method::is_method_id(jmethodID mid) {
2138   Method* m = resolve_jmethod_id(mid);
2139   assert(m != NULL, "should be called with non-null method");
2140   InstanceKlass* ik = m->method_holder();
2141   ClassLoaderData* cld = ik->class_loader_data();
2142   if (cld->jmethod_ids() == NULL) return false;
2143   return (cld->jmethod_ids()->contains((Method**)mid));
2144 }
2145 
2146 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2147   if (mid == NULL) return NULL;
2148   Method* o = resolve_jmethod_id(mid);
2149   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2150     return NULL;
2151   }
2152   return o;
2153 };
2154 
2155 void Method::set_on_stack(const bool value) {
2156   // Set both the method itself and its constant pool.  The constant pool
2157   // on stack means some method referring to it is also on the stack.
2158   constants()->set_on_stack(value);
2159 
2160   bool already_set = on_stack();
2161   _access_flags.set_on_stack(value);
2162   if (value && !already_set) {
2163     MetadataOnStackMark::record(this);
2164   }
2165 }
2166 
2167 // Called when the class loader is unloaded to make all methods weak.
2168 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2169   loader_data->jmethod_ids()->clear_all_methods();
2170 }
2171 
2172 bool Method::has_method_vptr(const void* ptr) {
2173   Method m;
2174   // This assumes that the vtbl pointer is the first word of a C++ object.
2175   return dereference_vptr(&m) == dereference_vptr(ptr);
2176 }
2177 
2178 // Check that this pointer is valid by checking that the vtbl pointer matches
2179 bool Method::is_valid_method() const {
2180   if (this == NULL) {
2181     return false;
2182   } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2183     // Quick sanity check on pointer.
2184     return false;
2185   } else if (MetaspaceShared::is_in_shared_space(this)) {
2186     return MetaspaceShared::is_valid_shared_method(this);
2187   } else if (Metaspace::contains_non_shared(this)) {
2188     return has_method_vptr((const void*)this);
2189   } else {
2190     return false;
2191   }
2192 }
2193 
2194 #ifndef PRODUCT
2195 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2196   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2197 }
2198 #endif // PRODUCT
2199 
2200 
2201 // Printing
2202 
2203 #ifndef PRODUCT
2204 
2205 void Method::print_on(outputStream* st) const {
2206   ResourceMark rm;
2207   assert(is_method(), "must be method");
2208   st->print_cr("%s", internal_name());
2209   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2210   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2211   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2212   constants()->print_value_on(st); st->cr();
2213   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2214   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2215   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2216   st->print_cr(" - max stack:         %d",   max_stack());
2217   st->print_cr(" - max locals:        %d",   max_locals());
2218   st->print_cr(" - size of params:    %d",   size_of_parameters());
2219   st->print_cr(" - method size:       %d",   method_size());
2220   if (intrinsic_id() != vmIntrinsics::_none)
2221     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2222   if (highest_comp_level() != CompLevel_none)
2223     st->print_cr(" - highest level:     %d", highest_comp_level());
2224   st->print_cr(" - vtable index:      %d",   _vtable_index);
2225   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2226   st->print(   " - adapters:          ");
2227   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2228   if (a == NULL)
2229     st->print_cr(INTPTR_FORMAT, p2i(a));
2230   else
2231     a->print_adapter_on(st);
2232   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2233   st->print_cr(" - code size:         %d",   code_size());
2234   if (code_size() != 0) {
2235     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2236     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2237   }
2238   if (method_data() != NULL) {
2239     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2240   }
2241   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2242   if (checked_exceptions_length() > 0) {
2243     CheckedExceptionElement* table = checked_exceptions_start();
2244     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2245     if (Verbose) {
2246       for (int i = 0; i < checked_exceptions_length(); i++) {
2247         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2248       }
2249     }
2250   }
2251   if (has_linenumber_table()) {
2252     u_char* table = compressed_linenumber_table();
2253     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2254     if (Verbose) {
2255       CompressedLineNumberReadStream stream(table);
2256       while (stream.read_pair()) {
2257         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2258       }
2259     }
2260   }
2261   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2262   if (localvariable_table_length() > 0) {
2263     LocalVariableTableElement* table = localvariable_table_start();
2264     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2265     if (Verbose) {
2266       for (int i = 0; i < localvariable_table_length(); i++) {
2267         int bci = table[i].start_bci;
2268         int len = table[i].length;
2269         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2270         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2271         int slot = table[i].slot;
2272         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2273       }
2274     }
2275   }
2276   if (code() != NULL) {
2277     st->print   (" - compiled code: ");
2278     code()->print_value_on(st);
2279   }
2280   if (is_native()) {
2281     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2282     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2283   }
2284 }
2285 
2286 void Method::print_linkage_flags(outputStream* st) {
2287   access_flags().print_on(st);
2288   if (is_default_method()) {
2289     st->print("default ");
2290   }
2291   if (is_overpass()) {
2292     st->print("overpass ");
2293   }
2294 }
2295 #endif //PRODUCT
2296 
2297 void Method::print_value_on(outputStream* st) const {
2298   assert(is_method(), "must be method");
2299   st->print("%s", internal_name());
2300   print_address_on(st);
2301   st->print(" ");
2302   name()->print_value_on(st);
2303   st->print(" ");
2304   signature()->print_value_on(st);
2305   st->print(" in ");
2306   method_holder()->print_value_on(st);
2307   if (WizardMode) st->print("#%d", _vtable_index);
2308   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2309   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2310 }
2311 
2312 #if INCLUDE_SERVICES
2313 // Size Statistics
2314 void Method::collect_statistics(KlassSizeStats *sz) const {
2315   int mysize = sz->count(this);
2316   sz->_method_bytes += mysize;
2317   sz->_method_all_bytes += mysize;
2318   sz->_rw_bytes += mysize;
2319 
2320   if (constMethod()) {
2321     constMethod()->collect_statistics(sz);
2322   }
2323   if (method_data()) {
2324     method_data()->collect_statistics(sz);
2325   }
2326 }
2327 #endif // INCLUDE_SERVICES
2328 
2329 // LogTouchedMethods and PrintTouchedMethods
2330 
2331 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2332 // the Method may be garbage collected. Let's roll our own hash table.
2333 class TouchedMethodRecord : CHeapObj<mtTracing> {
2334 public:
2335   // It's OK to store Symbols here because they will NOT be GC'ed if
2336   // LogTouchedMethods is enabled.
2337   TouchedMethodRecord* _next;
2338   Symbol* _class_name;
2339   Symbol* _method_name;
2340   Symbol* _method_signature;
2341 };
2342 
2343 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2344 static TouchedMethodRecord** _touched_method_table = NULL;
2345 
2346 void Method::log_touched(TRAPS) {
2347 
2348   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2349   Symbol* my_class = klass_name();
2350   Symbol* my_name  = name();
2351   Symbol* my_sig   = signature();
2352 
2353   unsigned int hash = my_class->identity_hash() +
2354                       my_name->identity_hash() +
2355                       my_sig->identity_hash();
2356   juint index = juint(hash) % table_size;
2357 
2358   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2359   if (_touched_method_table == NULL) {
2360     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2361                                               mtTracing, CURRENT_PC);
2362     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2363   }
2364 
2365   TouchedMethodRecord* ptr = _touched_method_table[index];
2366   while (ptr) {
2367     if (ptr->_class_name       == my_class &&
2368         ptr->_method_name      == my_name &&
2369         ptr->_method_signature == my_sig) {
2370       return;
2371     }
2372     if (ptr->_next == NULL) break;
2373     ptr = ptr->_next;
2374   }
2375   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2376   my_class->set_permanent();  // prevent reclaimed by GC
2377   my_name->set_permanent();
2378   my_sig->set_permanent();
2379   nptr->_class_name         = my_class;
2380   nptr->_method_name        = my_name;
2381   nptr->_method_signature   = my_sig;
2382   nptr->_next               = NULL;
2383 
2384   if (ptr == NULL) {
2385     // first
2386     _touched_method_table[index] = nptr;
2387   } else {
2388     ptr->_next = nptr;
2389   }
2390 }
2391 
2392 void Method::print_touched_methods(outputStream* out) {
2393   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2394   out->print_cr("# Method::print_touched_methods version 1");
2395   if (_touched_method_table) {
2396     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2397       TouchedMethodRecord* ptr = _touched_method_table[i];
2398       while(ptr) {
2399         ptr->_class_name->print_symbol_on(out);       out->print(".");
2400         ptr->_method_name->print_symbol_on(out);      out->print(":");
2401         ptr->_method_signature->print_symbol_on(out); out->cr();
2402         ptr = ptr->_next;
2403       }
2404     }
2405   }
2406 }
2407 
2408 // Verification
2409 
2410 void Method::verify_on(outputStream* st) {
2411   guarantee(is_method(), "object must be method");
2412   guarantee(constants()->is_constantPool(), "should be constant pool");
2413   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2414   MethodData* md = method_data();
2415   guarantee(md == NULL ||
2416       md->is_methodData(), "should be method data");
2417 }
--- EOF ---