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