rev 56251 : imported patch 8226705-v1
rev 56252 : imported patch 8226705-v2

   1 /*
   2  * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoaderDataGraph.hpp"
  27 #include "classfile/metadataOnStackMark.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "code/debugInfoRec.hpp"
  31 #include "gc/shared/collectedHeap.inline.hpp"
  32 #include "interpreter/bytecodeStream.hpp"
  33 #include "interpreter/bytecodeTracer.hpp"
  34 #include "interpreter/bytecodes.hpp"
  35 #include "interpreter/interpreter.hpp"
  36 #include "interpreter/oopMapCache.hpp"
  37 #include "memory/allocation.inline.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceClosure.hpp"
  41 #include "memory/metaspaceShared.hpp"
  42 #include "memory/oopFactory.hpp"
  43 #include "memory/resourceArea.hpp"
  44 #include "memory/universe.hpp"
  45 #include "oops/constMethod.hpp"
  46 #include "oops/constantPool.hpp"
  47 #include "oops/method.inline.hpp"
  48 #include "oops/methodData.hpp"
  49 #include "oops/objArrayKlass.hpp"
  50 #include "oops/objArrayOop.inline.hpp"
  51 #include "oops/oop.inline.hpp"
  52 #include "oops/symbol.hpp"
  53 #include "prims/jvmtiExport.hpp"
  54 #include "prims/methodHandles.hpp"
  55 #include "prims/nativeLookup.hpp"
  56 #include "runtime/arguments.hpp"
  57 #include "runtime/compilationPolicy.hpp"
  58 #include "runtime/frame.inline.hpp"
  59 #include "runtime/handles.inline.hpp"
  60 #include "runtime/init.hpp"
  61 #include "runtime/orderAccess.hpp"
  62 #include "runtime/relocator.hpp"
  63 #include "runtime/safepointVerifiers.hpp"
  64 #include "runtime/sharedRuntime.hpp"
  65 #include "runtime/signature.hpp"
  66 #include "utilities/align.hpp"
  67 #include "utilities/quickSort.hpp"
  68 #include "utilities/vmError.hpp"
  69 #include "utilities/xmlstream.hpp"
  70 
  71 // Implementation of Method
  72 
  73 Method* Method::allocate(ClassLoaderData* loader_data,
  74                          int byte_code_size,
  75                          AccessFlags access_flags,
  76                          InlineTableSizes* sizes,
  77                          ConstMethod::MethodType method_type,
  78                          TRAPS) {
  79   assert(!access_flags.is_native() || byte_code_size == 0,
  80          "native methods should not contain byte codes");
  81   ConstMethod* cm = ConstMethod::allocate(loader_data,
  82                                           byte_code_size,
  83                                           sizes,
  84                                           method_type,
  85                                           CHECK_NULL);
  86   int size = Method::size(access_flags.is_native());
  87   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  88 }
  89 
  90 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  91   NoSafepointVerifier no_safepoint;
  92   set_constMethod(xconst);
  93   set_access_flags(access_flags);
  94   set_intrinsic_id(vmIntrinsics::_none);
  95   set_force_inline(false);
  96   set_hidden(false);
  97   set_dont_inline(false);
  98   set_has_injected_profile(false);
  99   set_method_data(NULL);
 100   clear_method_counters();
 101   set_vtable_index(Method::garbage_vtable_index);
 102 
 103   // Fix and bury in Method*
 104   set_interpreter_entry(NULL); // sets i2i entry and from_int
 105   set_adapter_entry(NULL);
 106   Method::clear_code(); // from_c/from_i get set to c2i/i2i
 107 
 108   if (access_flags.is_native()) {
 109     clear_native_function();
 110     set_signature_handler(NULL);
 111   }
 112 
 113   NOT_PRODUCT(set_compiled_invocation_count(0);)
 114 }
 115 
 116 // Release Method*.  The nmethod will be gone when we get here because
 117 // we've walked the code cache.
 118 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 119   MetadataFactory::free_metadata(loader_data, constMethod());
 120   set_constMethod(NULL);
 121 #if INCLUDE_JVMCI
 122   if (method_data()) {
 123     FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
 124   }
 125 #endif
 126   MetadataFactory::free_metadata(loader_data, method_data());
 127   set_method_data(NULL);
 128   MetadataFactory::free_metadata(loader_data, method_counters());
 129   clear_method_counters();
 130   // The nmethod will be gone when we get here.
 131   if (code() != NULL) _code = NULL;
 132 }
 133 
 134 address Method::get_i2c_entry() {
 135   assert(adapter() != NULL, "must have");
 136   return adapter()->get_i2c_entry();
 137 }
 138 
 139 address Method::get_c2i_entry() {
 140   assert(adapter() != NULL, "must have");
 141   return adapter()->get_c2i_entry();
 142 }
 143 
 144 address Method::get_c2i_unverified_entry() {
 145   assert(adapter() != NULL, "must have");
 146   return adapter()->get_c2i_unverified_entry();
 147 }
 148 
 149 address Method::get_c2i_no_clinit_check_entry() {
 150   assert(VM_Version::supports_fast_class_init_checks(), "");
 151   assert(adapter() != NULL, "must have");
 152   return adapter()->get_c2i_no_clinit_check_entry();
 153 }
 154 
 155 char* Method::name_and_sig_as_C_string() const {
 156   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 157 }
 158 
 159 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 160   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 161 }
 162 
 163 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 164   const char* klass_name = klass->external_name();
 165   int klass_name_len  = (int)strlen(klass_name);
 166   int method_name_len = method_name->utf8_length();
 167   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 168   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 169   strcpy(dest, klass_name);
 170   dest[klass_name_len] = '.';
 171   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 172   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 173   dest[len] = 0;
 174   return dest;
 175 }
 176 
 177 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 178   Symbol* klass_name = klass->name();
 179   klass_name->as_klass_external_name(buf, size);
 180   int len = (int)strlen(buf);
 181 
 182   if (len < size - 1) {
 183     buf[len++] = '.';
 184 
 185     method_name->as_C_string(&(buf[len]), size - len);
 186     len = (int)strlen(buf);
 187 
 188     signature->as_C_string(&(buf[len]), size - len);
 189   }
 190 
 191   return buf;
 192 }
 193 
 194 const char* Method::external_name() const {
 195   return external_name(constants()->pool_holder(), name(), signature());
 196 }
 197 
 198 void Method::print_external_name(outputStream *os) const {
 199   print_external_name(os, constants()->pool_holder(), name(), signature());
 200 }
 201 
 202 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
 203   stringStream ss;
 204   print_external_name(&ss, klass, method_name, signature);
 205   return ss.as_string();
 206 }
 207 
 208 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
 209   signature->print_as_signature_external_return_type(os);
 210   os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
 211   signature->print_as_signature_external_parameters(os);
 212   os->print(")");
 213 }
 214 
 215 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 216   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 217   // access exception table
 218   ExceptionTable table(mh());
 219   int length = table.length();
 220   // iterate through all entries sequentially
 221   constantPoolHandle pool(THREAD, mh->constants());
 222   for (int i = 0; i < length; i ++) {
 223     //reacquire the table in case a GC happened
 224     ExceptionTable table(mh());
 225     int beg_bci = table.start_pc(i);
 226     int end_bci = table.end_pc(i);
 227     assert(beg_bci <= end_bci, "inconsistent exception table");
 228     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 229       // exception handler bci range covers throw_bci => investigate further
 230       int handler_bci = table.handler_pc(i);
 231       int klass_index = table.catch_type_index(i);
 232       if (klass_index == 0) {
 233         return handler_bci;
 234       } else if (ex_klass == NULL) {
 235         return handler_bci;
 236       } else {
 237         // we know the exception class => get the constraint class
 238         // this may require loading of the constraint class; if verification
 239         // fails or some other exception occurs, return handler_bci
 240         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 241         assert(k != NULL, "klass not loaded");
 242         if (ex_klass->is_subtype_of(k)) {
 243           return handler_bci;
 244         }
 245       }
 246     }
 247   }
 248 
 249   return -1;
 250 }
 251 
 252 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 253   methodHandle h_this(Thread::current(), this);
 254   // Only GC uses the OopMapCache during thread stack root scanning
 255   // any other uses generate an oopmap but do not save it in the cache.
 256   if (Universe::heap()->is_gc_active()) {
 257     method_holder()->mask_for(h_this, bci, mask);
 258   } else {
 259     OopMapCache::compute_one_oop_map(h_this, bci, mask);
 260   }
 261   return;
 262 }
 263 
 264 
 265 int Method::bci_from(address bcp) const {
 266   if (is_native() && bcp == 0) {
 267     return 0;
 268   }
 269 #ifdef ASSERT
 270   {
 271     ResourceMark rm;
 272     assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
 273            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 274            p2i(bcp), name_and_sig_as_C_string());
 275   }
 276 #endif
 277   return bcp - code_base();
 278 }
 279 
 280 
 281 int Method::validate_bci(int bci) const {
 282   return (bci == 0 || bci < code_size()) ? bci : -1;
 283 }
 284 
 285 // Return bci if it appears to be a valid bcp
 286 // Return -1 otherwise.
 287 // Used by profiling code, when invalid data is a possibility.
 288 // The caller is responsible for validating the Method* itself.
 289 int Method::validate_bci_from_bcp(address bcp) const {
 290   // keep bci as -1 if not a valid bci
 291   int bci = -1;
 292   if (bcp == 0 || bcp == code_base()) {
 293     // code_size() may return 0 and we allow 0 here
 294     // the method may be native
 295     bci = 0;
 296   } else if (contains(bcp)) {
 297     bci = bcp - code_base();
 298   }
 299   // Assert that if we have dodged any asserts, bci is negative.
 300   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 301   return bci;
 302 }
 303 
 304 address Method::bcp_from(int bci) const {
 305   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 306          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 307   address bcp = code_base() + bci;
 308   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 309   return bcp;
 310 }
 311 
 312 address Method::bcp_from(address bcp) const {
 313   if (is_native() && bcp == NULL) {
 314     return code_base();
 315   } else {
 316     return bcp;
 317   }
 318 }
 319 
 320 int Method::size(bool is_native) {
 321   // If native, then include pointers for native_function and signature_handler
 322   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 323   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 324   return align_metadata_size(header_size() + extra_words);
 325 }
 326 
 327 
 328 Symbol* Method::klass_name() const {
 329   return method_holder()->name();
 330 }
 331 
 332 
 333 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 334   log_trace(cds)("Iter(Method): %p", this);
 335 
 336   it->push(&_constMethod);
 337   it->push(&_method_data);
 338   it->push(&_method_counters);
 339 }
 340 
 341 // Attempt to return method oop to original state.  Clear any pointers
 342 // (to objects outside the shared spaces).  We won't be able to predict
 343 // where they should point in a new JVM.  Further initialize some
 344 // entries now in order allow them to be write protected later.
 345 
 346 void Method::remove_unshareable_info() {
 347   unlink_method();
 348 }
 349 
 350 void Method::set_vtable_index(int index) {
 351   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 352     // At runtime initialize_vtable is rerun as part of link_class_impl()
 353     // for a shared class loaded by the non-boot loader to obtain the loader
 354     // constraints based on the runtime classloaders' context.
 355     return; // don't write into the shared class
 356   } else {
 357     _vtable_index = index;
 358   }
 359 }
 360 
 361 void Method::set_itable_index(int index) {
 362   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 363     // At runtime initialize_itable is rerun as part of link_class_impl()
 364     // for a shared class loaded by the non-boot loader to obtain the loader
 365     // constraints based on the runtime classloaders' context. The dumptime
 366     // itable index should be the same as the runtime index.
 367     assert(_vtable_index == itable_index_max - index,
 368            "archived itable index is different from runtime index");
 369     return; // don’t write into the shared class
 370   } else {
 371     _vtable_index = itable_index_max - index;
 372   }
 373   assert(valid_itable_index(), "");
 374 }
 375 
 376 
 377 
 378 bool Method::was_executed_more_than(int n) {
 379   // Invocation counter is reset when the Method* is compiled.
 380   // If the method has compiled code we therefore assume it has
 381   // be excuted more than n times.
 382   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 383     // interpreter doesn't bump invocation counter of trivial methods
 384     // compiler does not bump invocation counter of compiled methods
 385     return true;
 386   }
 387   else if ((method_counters() != NULL &&
 388             method_counters()->invocation_counter()->carry()) ||
 389            (method_data() != NULL &&
 390             method_data()->invocation_counter()->carry())) {
 391     // The carry bit is set when the counter overflows and causes
 392     // a compilation to occur.  We don't know how many times
 393     // the counter has been reset, so we simply assume it has
 394     // been executed more than n times.
 395     return true;
 396   } else {
 397     return invocation_count() > n;
 398   }
 399 }
 400 
 401 void Method::print_invocation_count() {
 402   if (is_static()) tty->print("static ");
 403   if (is_final()) tty->print("final ");
 404   if (is_synchronized()) tty->print("synchronized ");
 405   if (is_native()) tty->print("native ");
 406   tty->print("%s::", method_holder()->external_name());
 407   name()->print_symbol_on(tty);
 408   signature()->print_symbol_on(tty);
 409 
 410   if (WizardMode) {
 411     // dump the size of the byte codes
 412     tty->print(" {%d}", code_size());
 413   }
 414   tty->cr();
 415 
 416   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 417   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 418   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 419 #ifndef PRODUCT
 420   if (CountCompiledCalls) {
 421     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 422   }
 423 #endif
 424 }
 425 
 426 // Build a MethodData* object to hold information about this method
 427 // collected in the interpreter.
 428 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 429   // Do not profile the method if metaspace has hit an OOM previously
 430   // allocating profiling data. Callers clear pending exception so don't
 431   // add one here.
 432   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 433     return;
 434   }
 435 
 436   // Grab a lock here to prevent multiple
 437   // MethodData*s from being created.
 438   MutexLocker ml(MethodData_lock, THREAD);
 439   if (method->method_data() == NULL) {
 440     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 441     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 442     if (HAS_PENDING_EXCEPTION) {
 443       CompileBroker::log_metaspace_failure();
 444       ClassLoaderDataGraph::set_metaspace_oom(true);
 445       return;   // return the exception (which is cleared)
 446     }
 447 
 448     method->set_method_data(method_data);
 449     if (PrintMethodData && (Verbose || WizardMode)) {
 450       ResourceMark rm(THREAD);
 451       tty->print("build_interpreter_method_data for ");
 452       method->print_name(tty);
 453       tty->cr();
 454       // At the end of the run, the MDO, full of data, will be dumped.
 455     }
 456   }
 457 }
 458 
 459 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 460   // Do not profile the method if metaspace has hit an OOM previously
 461   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 462     return NULL;
 463   }
 464 
 465   methodHandle mh(m);
 466   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 467   if (HAS_PENDING_EXCEPTION) {
 468     CompileBroker::log_metaspace_failure();
 469     ClassLoaderDataGraph::set_metaspace_oom(true);
 470     return NULL;   // return the exception (which is cleared)
 471   }
 472   if (!mh->init_method_counters(counters)) {
 473     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 474   }
 475 
 476   if (LogTouchedMethods) {
 477     mh->log_touched(CHECK_NULL);
 478   }
 479 
 480   return mh->method_counters();
 481 }
 482 
 483 bool Method::init_method_counters(MethodCounters* counters) {
 484   // Try to install a pointer to MethodCounters, return true on success.
 485   return Atomic::replace_if_null(counters, &_method_counters);
 486 }
 487 
 488 int Method::extra_stack_words() {
 489   // not an inline function, to avoid a header dependency on Interpreter
 490   return extra_stack_entries() * Interpreter::stackElementSize;
 491 }
 492 
 493 
 494 void Method::compute_size_of_parameters(Thread *thread) {
 495   ArgumentSizeComputer asc(signature());
 496   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 497 }
 498 
 499 BasicType Method::result_type() const {
 500   ResultTypeFinder rtf(signature());
 501   return rtf.type();
 502 }
 503 
 504 
 505 bool Method::is_empty_method() const {
 506   return  code_size() == 1
 507       && *code_base() == Bytecodes::_return;
 508 }
 509 
 510 
 511 bool Method::is_vanilla_constructor() const {
 512   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 513   // which only calls the superclass vanilla constructor and possibly does stores of
 514   // zero constants to local fields:
 515   //
 516   //   aload_0
 517   //   invokespecial
 518   //   indexbyte1
 519   //   indexbyte2
 520   //
 521   // followed by an (optional) sequence of:
 522   //
 523   //   aload_0
 524   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 525   //   putfield
 526   //   indexbyte1
 527   //   indexbyte2
 528   //
 529   // followed by:
 530   //
 531   //   return
 532 
 533   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 534   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 535   int size = code_size();
 536   // Check if size match
 537   if (size == 0 || size % 5 != 0) return false;
 538   address cb = code_base();
 539   int last = size - 1;
 540   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 541     // Does not call superclass default constructor
 542     return false;
 543   }
 544   // Check optional sequence
 545   for (int i = 4; i < last; i += 5) {
 546     if (cb[i] != Bytecodes::_aload_0) return false;
 547     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 548     if (cb[i+2] != Bytecodes::_putfield) return false;
 549   }
 550   return true;
 551 }
 552 
 553 
 554 bool Method::compute_has_loops_flag() {
 555   BytecodeStream bcs(this);
 556   Bytecodes::Code bc;
 557 
 558   while ((bc = bcs.next()) >= 0) {
 559     switch( bc ) {
 560       case Bytecodes::_ifeq:
 561       case Bytecodes::_ifnull:
 562       case Bytecodes::_iflt:
 563       case Bytecodes::_ifle:
 564       case Bytecodes::_ifne:
 565       case Bytecodes::_ifnonnull:
 566       case Bytecodes::_ifgt:
 567       case Bytecodes::_ifge:
 568       case Bytecodes::_if_icmpeq:
 569       case Bytecodes::_if_icmpne:
 570       case Bytecodes::_if_icmplt:
 571       case Bytecodes::_if_icmpgt:
 572       case Bytecodes::_if_icmple:
 573       case Bytecodes::_if_icmpge:
 574       case Bytecodes::_if_acmpeq:
 575       case Bytecodes::_if_acmpne:
 576       case Bytecodes::_goto:
 577       case Bytecodes::_jsr:
 578         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 579         break;
 580 
 581       case Bytecodes::_goto_w:
 582       case Bytecodes::_jsr_w:
 583         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 584         break;
 585 
 586       default:
 587         break;
 588     }
 589   }
 590   _access_flags.set_loops_flag_init();
 591   return _access_flags.has_loops();
 592 }
 593 
 594 bool Method::is_final_method(AccessFlags class_access_flags) const {
 595   // or "does_not_require_vtable_entry"
 596   // default method or overpass can occur, is not final (reuses vtable entry)
 597   // private methods in classes get vtable entries for backward class compatibility.
 598   if (is_overpass() || is_default_method())  return false;
 599   return is_final() || class_access_flags.is_final();
 600 }
 601 
 602 bool Method::is_final_method() const {
 603   return is_final_method(method_holder()->access_flags());
 604 }
 605 
 606 bool Method::is_default_method() const {
 607   if (method_holder() != NULL &&
 608       method_holder()->is_interface() &&
 609       !is_abstract() && !is_private()) {
 610     return true;
 611   } else {
 612     return false;
 613   }
 614 }
 615 
 616 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 617   if (is_final_method(class_access_flags))  return true;
 618 #ifdef ASSERT
 619   ResourceMark rm;
 620   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 621   if (class_access_flags.is_interface()) {
 622       assert(is_nonv == is_static() || is_nonv == is_private(),
 623              "nonvirtual unexpected for non-static, non-private: %s",
 624              name_and_sig_as_C_string());
 625   }
 626 #endif
 627   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 628   return vtable_index() == nonvirtual_vtable_index;
 629 }
 630 
 631 bool Method::can_be_statically_bound() const {
 632   return can_be_statically_bound(method_holder()->access_flags());
 633 }
 634 
 635 bool Method::can_be_statically_bound(InstanceKlass* context) const {
 636   return (method_holder() == context) && can_be_statically_bound();
 637 }
 638 
 639 bool Method::is_accessor() const {
 640   return is_getter() || is_setter();
 641 }
 642 
 643 bool Method::is_getter() const {
 644   if (code_size() != 5) return false;
 645   if (size_of_parameters() != 1) return false;
 646   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 647   if (java_code_at(1) != Bytecodes::_getfield) return false;
 648   switch (java_code_at(4)) {
 649     case Bytecodes::_ireturn:
 650     case Bytecodes::_lreturn:
 651     case Bytecodes::_freturn:
 652     case Bytecodes::_dreturn:
 653     case Bytecodes::_areturn:
 654       break;
 655     default:
 656       return false;
 657   }
 658   return true;
 659 }
 660 
 661 bool Method::is_setter() const {
 662   if (code_size() != 6) return false;
 663   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 664   switch (java_code_at(1)) {
 665     case Bytecodes::_iload_1:
 666     case Bytecodes::_aload_1:
 667     case Bytecodes::_fload_1:
 668       if (size_of_parameters() != 2) return false;
 669       break;
 670     case Bytecodes::_dload_1:
 671     case Bytecodes::_lload_1:
 672       if (size_of_parameters() != 3) return false;
 673       break;
 674     default:
 675       return false;
 676   }
 677   if (java_code_at(2) != Bytecodes::_putfield) return false;
 678   if (java_code_at(5) != Bytecodes::_return)   return false;
 679   return true;
 680 }
 681 
 682 bool Method::is_constant_getter() const {
 683   int last_index = code_size() - 1;
 684   // Check if the first 1-3 bytecodes are a constant push
 685   // and the last bytecode is a return.
 686   return (2 <= code_size() && code_size() <= 4 &&
 687           Bytecodes::is_const(java_code_at(0)) &&
 688           Bytecodes::length_for(java_code_at(0)) == last_index &&
 689           Bytecodes::is_return(java_code_at(last_index)));
 690 }
 691 
 692 bool Method::is_initializer() const {
 693   return is_object_initializer() || is_static_initializer();
 694 }
 695 
 696 bool Method::has_valid_initializer_flags() const {
 697   return (is_static() ||
 698           method_holder()->major_version() < 51);
 699 }
 700 
 701 bool Method::is_static_initializer() const {
 702   // For classfiles version 51 or greater, ensure that the clinit method is
 703   // static.  Non-static methods with the name "<clinit>" are not static
 704   // initializers. (older classfiles exempted for backward compatibility)
 705   return name() == vmSymbols::class_initializer_name() &&
 706          has_valid_initializer_flags();
 707 }
 708 
 709 bool Method::is_object_initializer() const {
 710    return name() == vmSymbols::object_initializer_name();
 711 }
 712 
 713 bool Method::needs_clinit_barrier() const {
 714   return is_static() && !method_holder()->is_initialized();
 715 }
 716 
 717 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 718   int length = method->checked_exceptions_length();
 719   if (length == 0) {  // common case
 720     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 721   } else {
 722     methodHandle h_this(THREAD, method);
 723     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 724     objArrayHandle mirrors (THREAD, m_oop);
 725     for (int i = 0; i < length; i++) {
 726       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 727       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 728       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 729       mirrors->obj_at_put(i, k->java_mirror());
 730     }
 731     return mirrors;
 732   }
 733 };
 734 
 735 
 736 int Method::line_number_from_bci(int bci) const {
 737   int best_bci  =  0;
 738   int best_line = -1;
 739   if (bci == SynchronizationEntryBCI) bci = 0;
 740   if (0 <= bci && bci < code_size() && has_linenumber_table()) {
 741     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 742     // Not necessarily sorted and not necessarily one-to-one.
 743     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 744     while (stream.read_pair()) {
 745       if (stream.bci() == bci) {
 746         // perfect match
 747         return stream.line();
 748       } else {
 749         // update best_bci/line
 750         if (stream.bci() < bci && stream.bci() >= best_bci) {
 751           best_bci  = stream.bci();
 752           best_line = stream.line();
 753         }
 754       }
 755     }
 756   }
 757   return best_line;
 758 }
 759 
 760 
 761 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 762   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 763     Thread *thread = Thread::current();
 764     Symbol* klass_name = constants()->klass_name_at(klass_index);
 765     Handle loader(thread, method_holder()->class_loader());
 766     Handle prot  (thread, method_holder()->protection_domain());
 767     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 768   } else {
 769     return true;
 770   }
 771 }
 772 
 773 
 774 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 775   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 776   if (must_be_resolved) {
 777     // Make sure klass is resolved in constantpool.
 778     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 779   }
 780   return is_klass_loaded_by_klass_index(klass_index);
 781 }
 782 
 783 
 784 void Method::set_native_function(address function, bool post_event_flag) {
 785   assert(function != NULL, "use clear_native_function to unregister natives");
 786   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 787   address* native_function = native_function_addr();
 788 
 789   // We can see racers trying to place the same native function into place. Once
 790   // is plenty.
 791   address current = *native_function;
 792   if (current == function) return;
 793   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 794       function != NULL) {
 795     // native_method_throw_unsatisfied_link_error_entry() should only
 796     // be passed when post_event_flag is false.
 797     assert(function !=
 798       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 799       "post_event_flag mis-match");
 800 
 801     // post the bind event, and possible change the bind function
 802     JvmtiExport::post_native_method_bind(this, &function);
 803   }
 804   *native_function = function;
 805   // This function can be called more than once. We must make sure that we always
 806   // use the latest registered method -> check if a stub already has been generated.
 807   // If so, we have to make it not_entrant.
 808   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 809   if (nm != NULL) {
 810     nm->make_not_entrant();
 811   }
 812 }
 813 
 814 
 815 bool Method::has_native_function() const {
 816   if (is_method_handle_intrinsic())
 817     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 818   address func = native_function();
 819   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 820 }
 821 
 822 
 823 void Method::clear_native_function() {
 824   // Note: is_method_handle_intrinsic() is allowed here.
 825   set_native_function(
 826     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 827     !native_bind_event_is_interesting);
 828   this->unlink_code();
 829 }
 830 
 831 
 832 void Method::set_signature_handler(address handler) {
 833   address* signature_handler =  signature_handler_addr();
 834   *signature_handler = handler;
 835 }
 836 
 837 
 838 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 839   assert(reason != NULL, "must provide a reason");
 840   if (PrintCompilation && report) {
 841     ttyLocker ttyl;
 842     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 843     if (comp_level == CompLevel_all) {
 844       tty->print("all levels ");
 845     } else {
 846       tty->print("level %d ", comp_level);
 847     }
 848     this->print_short_name(tty);
 849     int size = this->code_size();
 850     if (size > 0) {
 851       tty->print(" (%d bytes)", size);
 852     }
 853     if (reason != NULL) {
 854       tty->print("   %s", reason);
 855     }
 856     tty->cr();
 857   }
 858   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 859     ttyLocker ttyl;
 860     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 861                      os::current_thread_id(), is_osr, comp_level);
 862     if (reason != NULL) {
 863       xtty->print(" reason=\'%s\'", reason);
 864     }
 865     xtty->method(this);
 866     xtty->stamp();
 867     xtty->end_elem();
 868   }
 869 }
 870 
 871 bool Method::is_always_compilable() const {
 872   // Generated adapters must be compiled
 873   if (is_method_handle_intrinsic() && is_synthetic()) {
 874     assert(!is_not_c1_compilable(), "sanity check");
 875     assert(!is_not_c2_compilable(), "sanity check");
 876     return true;
 877   }
 878 
 879   return false;
 880 }
 881 
 882 bool Method::is_not_compilable(int comp_level) const {
 883   if (number_of_breakpoints() > 0)
 884     return true;
 885   if (is_always_compilable())
 886     return false;
 887   if (comp_level == CompLevel_any)
 888     return is_not_c1_compilable() || is_not_c2_compilable();
 889   if (is_c1_compile(comp_level))
 890     return is_not_c1_compilable();
 891   if (is_c2_compile(comp_level))
 892     return is_not_c2_compilable();
 893   return false;
 894 }
 895 
 896 // call this when compiler finds that this method is not compilable
 897 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
 898   if (is_always_compilable()) {
 899     // Don't mark a method which should be always compilable
 900     return;
 901   }
 902   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 903   if (comp_level == CompLevel_all) {
 904     set_not_c1_compilable();
 905     set_not_c2_compilable();
 906   } else {
 907     if (is_c1_compile(comp_level))
 908       set_not_c1_compilable();
 909     if (is_c2_compile(comp_level))
 910       set_not_c2_compilable();
 911   }
 912   CompilationPolicy::policy()->disable_compilation(this);
 913   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 914 }
 915 
 916 bool Method::is_not_osr_compilable(int comp_level) const {
 917   if (is_not_compilable(comp_level))
 918     return true;
 919   if (comp_level == CompLevel_any)
 920     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 921   if (is_c1_compile(comp_level))
 922     return is_not_c1_osr_compilable();
 923   if (is_c2_compile(comp_level))
 924     return is_not_c2_osr_compilable();
 925   return false;
 926 }
 927 
 928 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
 929   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 930   if (comp_level == CompLevel_all) {
 931     set_not_c1_osr_compilable();
 932     set_not_c2_osr_compilable();
 933   } else {
 934     if (is_c1_compile(comp_level))
 935       set_not_c1_osr_compilable();
 936     if (is_c2_compile(comp_level))
 937       set_not_c2_osr_compilable();
 938   }
 939   CompilationPolicy::policy()->disable_compilation(this);
 940   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 941 }
 942 
 943 // Revert to using the interpreter and clear out the nmethod
 944 void Method::clear_code() {

 945   // this may be NULL if c2i adapters have not been made yet
 946   // Only should happen at allocate time.
 947   if (adapter() == NULL) {
 948     _from_compiled_entry    = NULL;
 949   } else {
 950     _from_compiled_entry    = adapter()->get_c2i_entry();
 951   }
 952   OrderAccess::storestore();
 953   _from_interpreted_entry = _i2i_entry;
 954   OrderAccess::storestore();
 955   _code = NULL;
 956 }
 957 
 958 void Method::unlink_code(CompiledMethod *compare) {
 959   MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
 960   // We need to check if either the _code or _from_compiled_code_entry_point
 961   // refer to this nmethod because there is a race in setting these two fields
 962   // in Method* as seen in bugid 4947125.
 963   // If the vep() points to the zombie nmethod, the memory for the nmethod
 964   // could be flushed and the compiler and vtable stubs could still call
 965   // through it.
 966   if (code() == compare ||
 967       from_compiled_entry() == compare->verified_entry_point()) {
 968     clear_code();
 969   }
 970 }
 971 
 972 void Method::unlink_code() {
 973   MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
 974   clear_code();
 975 }
 976 
 977 #if INCLUDE_CDS
 978 // Called by class data sharing to remove any entry points (which are not shared)
 979 void Method::unlink_method() {
 980   _code = NULL;
 981 
 982   assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
 983   // Set the values to what they should be at run time. Note that
 984   // this Method can no longer be executed during dump time.
 985   _i2i_entry = Interpreter::entry_for_cds_method(this);
 986   _from_interpreted_entry = _i2i_entry;
 987 
 988   if (DynamicDumpSharedSpaces) {
 989     assert(_from_compiled_entry != NULL, "sanity");
 990   } else {
 991     // TODO: Simplify the adapter trampoline allocation for static archiving.
 992     //       Remove the use of CDSAdapterHandlerEntry.
 993     CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 994     constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 995     _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 996     assert(*((int*)_from_compiled_entry) == 0,
 997            "must be NULL during dump time, to be initialized at run time");
 998   }
 999 
1000   if (is_native()) {
1001     *native_function_addr() = NULL;
1002     set_signature_handler(NULL);
1003   }
1004   NOT_PRODUCT(set_compiled_invocation_count(0);)
1005 
1006   set_method_data(NULL);
1007   clear_method_counters();
1008 }
1009 #endif
1010 
1011 /****************************************************************************
1012 // The following illustrates how the entries work for CDS shared Methods:
1013 //
1014 // Our goal is to delay writing into a shared Method until it's compiled.
1015 // Hence, we want to determine the initial values for _i2i_entry,
1016 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1017 //
1018 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1019 // They also have similar signatures so that they will share the same
1020 // AdapterHandlerEntry.
1021 //
1022 // _adapter_trampoline points to a fixed location in the RW section of
1023 // the CDS archive. This location initially contains a NULL pointer. When the
1024 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1025 // dynamically, and its c2i/i2c entries are generated.
1026 //
1027 // _i2i_entry and _from_interpreted_entry initially points to the same
1028 // (fixed) location in the CODE section of the CDS archive. This contains
1029 // an unconditional branch to the actual entry for "zero_locals", which is
1030 // generated at run time and may be on an arbitrary address. Thus, the
1031 // unconditional branch is also generated at run time to jump to the correct
1032 // address.
1033 //
1034 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1035 // section. This address has enough space for an unconditional branch
1036 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1037 // initialized, and the address for the actual c2i_entry is known, we emit a
1038 // branch instruction here to branch to the actual c2i_entry.
1039 //
1040 // The effect of the extra branch on the i2i and c2i entries is negligible.
1041 //
1042 // The reason for putting _adapter_trampoline in RO is many shared Methods
1043 // share the same AdapterHandlerEntry, so we can save space in the RW section
1044 // by having the extra indirection.
1045 
1046 
1047 [Method A: RW]
1048   _constMethod ----> [ConstMethod: RO]
1049                        _adapter_trampoline -----------+
1050                                                       |
1051   _i2i_entry              (same value as method B)    |
1052   _from_interpreted_entry (same value as method B)    |
1053   _from_compiled_entry    (same value as method B)    |
1054                                                       |
1055                                                       |
1056 [Method B: RW]                               +--------+
1057   _constMethod ----> [ConstMethod: RO]       |
1058                        _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1059                                                                                  |
1060                                                  +-------------------------------+
1061                                                  |
1062                                                  +----> [AdapterHandlerEntry] (allocated at run time)
1063                                                               _fingerprint
1064                                                               _c2i_entry ---------------------------------+->[c2i entry..]
1065  _i2i_entry  -------------+                                   _i2c_entry ---------------+-> [i2c entry..] |
1066  _from_interpreted_entry  |                                   _c2i_unverified_entry     |                 |
1067          |                |                                   _c2i_no_clinit_check_entry|                 |
1068          |                |  (_cds_entry_table: CODE)                                   |                 |
1069          |                +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") |                 |
1070          |                |                               (allocated at run time)       |                 |
1071          |                |  ...                           [asm code ...]               |                 |
1072          +-[not compiled]-+  [n]: jmp _entry_table[n]                                   |                 |
1073          |                                                                              |                 |
1074          |                                                                              |                 |
1075          +-[compiled]-------------------------------------------------------------------+                 |
1076                                                                                                           |
1077  _from_compiled_entry------------>  (_c2i_entry_trampoline: CODE)                                         |
1078                                     [jmp c2i_entry] ------------------------------------------------------+
1079 
1080 ***/
1081 
1082 // Called when the method_holder is getting linked. Setup entrypoints so the method
1083 // is ready to be called from interpreter, compiler, and vtables.
1084 void Method::link_method(const methodHandle& h_method, TRAPS) {
1085   // If the code cache is full, we may reenter this function for the
1086   // leftover methods that weren't linked.
1087   if (is_shared()) {
1088     address entry = Interpreter::entry_for_cds_method(h_method);
1089     assert(entry != NULL && entry == _i2i_entry,
1090            "should be correctly set during dump time");
1091     if (adapter() != NULL) {
1092       return;
1093     }
1094     assert(entry == _from_interpreted_entry,
1095            "should be correctly set during dump time");
1096   } else if (_i2i_entry != NULL) {
1097     return;
1098   }
1099   assert( _code == NULL, "nothing compiled yet" );
1100 
1101   // Setup interpreter entrypoint
1102   assert(this == h_method(), "wrong h_method()" );
1103 
1104   if (!is_shared()) {
1105     assert(adapter() == NULL, "init'd to NULL");
1106     address entry = Interpreter::entry_for_method(h_method);
1107     assert(entry != NULL, "interpreter entry must be non-null");
1108     // Sets both _i2i_entry and _from_interpreted_entry
1109     set_interpreter_entry(entry);
1110   }
1111 
1112   // Don't overwrite already registered native entries.
1113   if (is_native() && !has_native_function()) {
1114     set_native_function(
1115       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1116       !native_bind_event_is_interesting);
1117   }
1118 
1119   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1120   // special handling of vtables.  An alternative is to make adapters more
1121   // lazily by calling make_adapter() from from_compiled_entry() for the
1122   // normal calls.  For vtable calls life gets more complicated.  When a
1123   // call-site goes mega-morphic we need adapters in all methods which can be
1124   // called from the vtable.  We need adapters on such methods that get loaded
1125   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1126   // problem we'll make these lazily later.
1127   (void) make_adapters(h_method, CHECK);
1128 
1129   // ONLY USE the h_method now as make_adapter may have blocked
1130 
1131 }
1132 
1133 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1134   // Adapters for compiled code are made eagerly here.  They are fairly
1135   // small (generally < 100 bytes) and quick to make (and cached and shared)
1136   // so making them eagerly shouldn't be too expensive.
1137   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1138   if (adapter == NULL ) {
1139     if (!is_init_completed()) {
1140       // Don't throw exceptions during VM initialization because java.lang.* classes
1141       // might not have been initialized, causing problems when constructing the
1142       // Java exception object.
1143       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1144     } else {
1145       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1146     }
1147   }
1148 
1149   if (mh->is_shared()) {
1150     assert(mh->adapter() == adapter, "must be");
1151     assert(mh->_from_compiled_entry != NULL, "must be");
1152   } else {
1153     mh->set_adapter_entry(adapter);
1154     mh->_from_compiled_entry = adapter->get_c2i_entry();
1155   }
1156   return adapter->get_c2i_entry();
1157 }
1158 
1159 void Method::restore_unshareable_info(TRAPS) {
1160   assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1161 
1162   // Since restore_unshareable_info can be called more than once for a method, don't
1163   // redo any work.
1164   if (adapter() == NULL) {
1165     methodHandle mh(THREAD, this);
1166     link_method(mh, CHECK);
1167   }
1168 }
1169 
1170 address Method::from_compiled_entry_no_trampoline() const {
1171   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1172   if (code) {
1173     return code->verified_entry_point();
1174   } else {
1175     return adapter()->get_c2i_entry();
1176   }
1177 }
1178 
1179 // The verified_code_entry() must be called when a invoke is resolved
1180 // on this method.
1181 
1182 // It returns the compiled code entry point, after asserting not null.
1183 // This function is called after potential safepoints so that nmethod
1184 // or adapter that it points to is still live and valid.
1185 // This function must not hit a safepoint!
1186 address Method::verified_code_entry() {
1187   debug_only(NoSafepointVerifier nsv;)
1188   assert(_from_compiled_entry != NULL, "must be set");
1189   return _from_compiled_entry;
1190 }
1191 
1192 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1193 // (could be racing a deopt).
1194 // Not inline to avoid circular ref.
1195 bool Method::check_code() const {
1196   // cached in a register or local.  There's a race on the value of the field.
1197   CompiledMethod *code = OrderAccess::load_acquire(&_code);
1198   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1199 }
1200 
1201 // Install compiled code.  Instantly it can execute.
1202 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1203   assert_lock_strong(CompiledMethod_lock);
1204   assert( code, "use clear_code to remove code" );
1205   assert( mh->check_code(), "" );
1206 
1207   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1208 
1209   // These writes must happen in this order, because the interpreter will
1210   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1211   // which jumps to _from_compiled_entry.
1212   mh->_code = code;             // Assign before allowing compiled code to exec
1213 
1214   int comp_level = code->comp_level();
1215   // In theory there could be a race here. In practice it is unlikely
1216   // and not worth worrying about.
1217   if (comp_level > mh->highest_comp_level()) {
1218     mh->set_highest_comp_level(comp_level);
1219   }
1220 
1221   OrderAccess::storestore();
1222   mh->_from_compiled_entry = code->verified_entry_point();
1223   OrderAccess::storestore();
1224   // Instantly compiled code can execute.
1225   if (!mh->is_method_handle_intrinsic())
1226     mh->_from_interpreted_entry = mh->get_i2c_entry();
1227 }
1228 
1229 
1230 bool Method::is_overridden_in(Klass* k) const {
1231   InstanceKlass* ik = InstanceKlass::cast(k);
1232 
1233   if (ik->is_interface()) return false;
1234 
1235   // If method is an interface, we skip it - except if it
1236   // is a miranda method
1237   if (method_holder()->is_interface()) {
1238     // Check that method is not a miranda method
1239     if (ik->lookup_method(name(), signature()) == NULL) {
1240       // No implementation exist - so miranda method
1241       return false;
1242     }
1243     return true;
1244   }
1245 
1246   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1247   if (!has_vtable_index()) {
1248     return false;
1249   } else {
1250     Method* vt_m = ik->method_at_vtable(vtable_index());
1251     return vt_m != this;
1252   }
1253 }
1254 
1255 
1256 // give advice about whether this Method* should be cached or not
1257 bool Method::should_not_be_cached() const {
1258   if (is_old()) {
1259     // This method has been redefined. It is either EMCP or obsolete
1260     // and we don't want to cache it because that would pin the method
1261     // down and prevent it from being collectible if and when it
1262     // finishes executing.
1263     return true;
1264   }
1265 
1266   // caching this method should be just fine
1267   return false;
1268 }
1269 
1270 
1271 /**
1272  *  Returns true if this is one of the specially treated methods for
1273  *  security related stack walks (like Reflection.getCallerClass).
1274  */
1275 bool Method::is_ignored_by_security_stack_walk() const {
1276   if (intrinsic_id() == vmIntrinsics::_invoke) {
1277     // This is Method.invoke() -- ignore it
1278     return true;
1279   }
1280   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1281     // This is an auxilary frame -- ignore it
1282     return true;
1283   }
1284   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1285     // This is an internal adapter frame for method handles -- ignore it
1286     return true;
1287   }
1288   return false;
1289 }
1290 
1291 
1292 // Constant pool structure for invoke methods:
1293 enum {
1294   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1295   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1296   _imcp_limit
1297 };
1298 
1299 // Test if this method is an MH adapter frame generated by Java code.
1300 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1301 bool Method::is_compiled_lambda_form() const {
1302   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1303 }
1304 
1305 // Test if this method is an internal MH primitive method.
1306 bool Method::is_method_handle_intrinsic() const {
1307   vmIntrinsics::ID iid = intrinsic_id();
1308   return (MethodHandles::is_signature_polymorphic(iid) &&
1309           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1310 }
1311 
1312 bool Method::has_member_arg() const {
1313   vmIntrinsics::ID iid = intrinsic_id();
1314   return (MethodHandles::is_signature_polymorphic(iid) &&
1315           MethodHandles::has_member_arg(iid));
1316 }
1317 
1318 // Make an instance of a signature-polymorphic internal MH primitive.
1319 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1320                                                          Symbol* signature,
1321                                                          TRAPS) {
1322   ResourceMark rm;
1323   methodHandle empty;
1324 
1325   InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1326   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1327   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1328   if (TraceMethodHandles) {
1329     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1330   }
1331 
1332   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1333   name->increment_refcount();
1334   signature->increment_refcount();
1335 
1336   int cp_length = _imcp_limit;
1337   ClassLoaderData* loader_data = holder->class_loader_data();
1338   constantPoolHandle cp;
1339   {
1340     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1341     cp = constantPoolHandle(THREAD, cp_oop);
1342   }
1343   cp->set_pool_holder(holder);
1344   cp->symbol_at_put(_imcp_invoke_name,       name);
1345   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1346   cp->set_has_preresolution();
1347 
1348   // decide on access bits:  public or not?
1349   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1350   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1351   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1352   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1353 
1354   methodHandle m;
1355   {
1356     InlineTableSizes sizes;
1357     Method* m_oop = Method::allocate(loader_data, 0,
1358                                      accessFlags_from(flags_bits), &sizes,
1359                                      ConstMethod::NORMAL, CHECK_(empty));
1360     m = methodHandle(THREAD, m_oop);
1361   }
1362   m->set_constants(cp());
1363   m->set_name_index(_imcp_invoke_name);
1364   m->set_signature_index(_imcp_invoke_signature);
1365   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1366   assert(m->signature() == signature, "");
1367   ResultTypeFinder rtf(signature);
1368   m->constMethod()->set_result_type(rtf.type());
1369   m->compute_size_of_parameters(THREAD);
1370   m->init_intrinsic_id();
1371   assert(m->is_method_handle_intrinsic(), "");
1372 #ifdef ASSERT
1373   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1374   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1375   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1376 #endif //ASSERT
1377 
1378   // Finally, set up its entry points.
1379   assert(m->can_be_statically_bound(), "");
1380   m->set_vtable_index(Method::nonvirtual_vtable_index);
1381   m->link_method(m, CHECK_(empty));
1382 
1383   if (TraceMethodHandles && (Verbose || WizardMode)) {
1384     ttyLocker ttyl;
1385     m->print_on(tty);
1386   }
1387 
1388   return m;
1389 }
1390 
1391 Klass* Method::check_non_bcp_klass(Klass* klass) {
1392   if (klass != NULL && klass->class_loader() != NULL) {
1393     if (klass->is_objArray_klass())
1394       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1395     return klass;
1396   }
1397   return NULL;
1398 }
1399 
1400 
1401 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1402                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1403   // Code below does not work for native methods - they should never get rewritten anyway
1404   assert(!m->is_native(), "cannot rewrite native methods");
1405   // Allocate new Method*
1406   AccessFlags flags = m->access_flags();
1407 
1408   ConstMethod* cm = m->constMethod();
1409   int checked_exceptions_len = cm->checked_exceptions_length();
1410   int localvariable_len = cm->localvariable_table_length();
1411   int exception_table_len = cm->exception_table_length();
1412   int method_parameters_len = cm->method_parameters_length();
1413   int method_annotations_len = cm->method_annotations_length();
1414   int parameter_annotations_len = cm->parameter_annotations_length();
1415   int type_annotations_len = cm->type_annotations_length();
1416   int default_annotations_len = cm->default_annotations_length();
1417 
1418   InlineTableSizes sizes(
1419       localvariable_len,
1420       new_compressed_linenumber_size,
1421       exception_table_len,
1422       checked_exceptions_len,
1423       method_parameters_len,
1424       cm->generic_signature_index(),
1425       method_annotations_len,
1426       parameter_annotations_len,
1427       type_annotations_len,
1428       default_annotations_len,
1429       0);
1430 
1431   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1432   Method* newm_oop = Method::allocate(loader_data,
1433                                       new_code_length,
1434                                       flags,
1435                                       &sizes,
1436                                       m->method_type(),
1437                                       CHECK_(methodHandle()));
1438   methodHandle newm (THREAD, newm_oop);
1439 
1440   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1441   ConstMethod* newcm = newm->constMethod();
1442   int new_const_method_size = newm->constMethod()->size();
1443 
1444   // This works because the source and target are both Methods. Some compilers
1445   // (e.g., clang) complain that the target vtable pointer will be stomped,
1446   // so cast away newm()'s and m()'s Methodness.
1447   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1448 
1449   // Create shallow copy of ConstMethod.
1450   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1451 
1452   // Reset correct method/const method, method size, and parameter info
1453   newm->set_constMethod(newcm);
1454   newm->constMethod()->set_code_size(new_code_length);
1455   newm->constMethod()->set_constMethod_size(new_const_method_size);
1456   assert(newm->code_size() == new_code_length, "check");
1457   assert(newm->method_parameters_length() == method_parameters_len, "check");
1458   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1459   assert(newm->exception_table_length() == exception_table_len, "check");
1460   assert(newm->localvariable_table_length() == localvariable_len, "check");
1461   // Copy new byte codes
1462   memcpy(newm->code_base(), new_code, new_code_length);
1463   // Copy line number table
1464   if (new_compressed_linenumber_size > 0) {
1465     memcpy(newm->compressed_linenumber_table(),
1466            new_compressed_linenumber_table,
1467            new_compressed_linenumber_size);
1468   }
1469   // Copy method_parameters
1470   if (method_parameters_len > 0) {
1471     memcpy(newm->method_parameters_start(),
1472            m->method_parameters_start(),
1473            method_parameters_len * sizeof(MethodParametersElement));
1474   }
1475   // Copy checked_exceptions
1476   if (checked_exceptions_len > 0) {
1477     memcpy(newm->checked_exceptions_start(),
1478            m->checked_exceptions_start(),
1479            checked_exceptions_len * sizeof(CheckedExceptionElement));
1480   }
1481   // Copy exception table
1482   if (exception_table_len > 0) {
1483     memcpy(newm->exception_table_start(),
1484            m->exception_table_start(),
1485            exception_table_len * sizeof(ExceptionTableElement));
1486   }
1487   // Copy local variable number table
1488   if (localvariable_len > 0) {
1489     memcpy(newm->localvariable_table_start(),
1490            m->localvariable_table_start(),
1491            localvariable_len * sizeof(LocalVariableTableElement));
1492   }
1493   // Copy stackmap table
1494   if (m->has_stackmap_table()) {
1495     int code_attribute_length = m->stackmap_data()->length();
1496     Array<u1>* stackmap_data =
1497       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1498     memcpy((void*)stackmap_data->adr_at(0),
1499            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1500     newm->set_stackmap_data(stackmap_data);
1501   }
1502 
1503   // copy annotations over to new method
1504   newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1505   return newm;
1506 }
1507 
1508 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1509   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1510   // because we are not loading from core libraries
1511   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1512   // which does not use the class default class loader so we check for its loader here
1513   const InstanceKlass* ik = InstanceKlass::cast(holder);
1514   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1515     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1516   }
1517 
1518   // see if the klass name is well-known:
1519   Symbol* klass_name = ik->name();
1520   return vmSymbols::find_sid(klass_name);
1521 }
1522 
1523 void Method::init_intrinsic_id() {
1524   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1525   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1526   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1527   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1528 
1529   // the klass name is well-known:
1530   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1531   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1532 
1533   // ditto for method and signature:
1534   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1535   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1536       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1537       && name_id == vmSymbols::NO_SID) {
1538     return;
1539   }
1540   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1541   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1542       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1543       && sig_id == vmSymbols::NO_SID) {
1544     return;
1545   }
1546   jshort flags = access_flags().as_short();
1547 
1548   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1549   if (id != vmIntrinsics::_none) {
1550     set_intrinsic_id(id);
1551     if (id == vmIntrinsics::_Class_cast) {
1552       // Even if the intrinsic is rejected, we want to inline this simple method.
1553       set_force_inline(true);
1554     }
1555     return;
1556   }
1557 
1558   // A few slightly irregular cases:
1559   switch (klass_id) {
1560   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1561     // Second chance: check in regular Math.
1562     switch (name_id) {
1563     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1564     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1565     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1566       // pretend it is the corresponding method in the non-strict class:
1567       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1568       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1569       break;
1570     default:
1571       break;
1572     }
1573     break;
1574 
1575   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1576   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1577   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1578     if (!is_native())  break;
1579     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1580     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1581       id = vmIntrinsics::_none;
1582     break;
1583 
1584   default:
1585     break;
1586   }
1587 
1588   if (id != vmIntrinsics::_none) {
1589     // Set up its iid.  It is an alias method.
1590     set_intrinsic_id(id);
1591     return;
1592   }
1593 }
1594 
1595 // These two methods are static since a GC may move the Method
1596 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1597   if (!THREAD->can_call_java()) {
1598     // There is nothing useful this routine can do from within the Compile thread.
1599     // Hopefully, the signature contains only well-known classes.
1600     // We could scan for this and return true/false, but the caller won't care.
1601     return false;
1602   }
1603   bool sig_is_loaded = true;
1604   Handle class_loader(THREAD, m->method_holder()->class_loader());
1605   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1606   ResourceMark rm(THREAD);
1607   Symbol*  signature = m->signature();
1608   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1609     if (ss.is_object()) {
1610       Symbol* sym = ss.as_symbol();
1611       Symbol*  name  = sym;
1612       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1613                                              protection_domain, THREAD);
1614       // We are loading classes eagerly. If a ClassNotFoundException or
1615       // a LinkageError was generated, be sure to ignore it.
1616       if (HAS_PENDING_EXCEPTION) {
1617         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1618             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1619           CLEAR_PENDING_EXCEPTION;
1620         } else {
1621           return false;
1622         }
1623       }
1624       if( klass == NULL) { sig_is_loaded = false; }
1625     }
1626   }
1627   return sig_is_loaded;
1628 }
1629 
1630 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1631   Handle class_loader(THREAD, m->method_holder()->class_loader());
1632   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1633   ResourceMark rm(THREAD);
1634   Symbol*  signature = m->signature();
1635   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1636     if (ss.type() == T_OBJECT) {
1637       Symbol* name = ss.as_symbol_or_null();
1638       if (name == NULL) return true;
1639       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1640       if (klass == NULL) return true;
1641     }
1642   }
1643   return false;
1644 }
1645 
1646 // Exposed so field engineers can debug VM
1647 void Method::print_short_name(outputStream* st) {
1648   ResourceMark rm;
1649 #ifdef PRODUCT
1650   st->print(" %s::", method_holder()->external_name());
1651 #else
1652   st->print(" %s::", method_holder()->internal_name());
1653 #endif
1654   name()->print_symbol_on(st);
1655   if (WizardMode) signature()->print_symbol_on(st);
1656   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1657     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1658 }
1659 
1660 // Comparer for sorting an object array containing
1661 // Method*s.
1662 static int method_comparator(Method* a, Method* b) {
1663   return a->name()->fast_compare(b->name());
1664 }
1665 
1666 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1667 // default_methods also uses this without the ordering for fast find_method
1668 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1669   int length = methods->length();
1670   if (length > 1) {
1671     {
1672       NoSafepointVerifier nsv;
1673       QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1674     }
1675     // Reset method ordering
1676     if (set_idnums) {
1677       for (int i = 0; i < length; i++) {
1678         Method* m = methods->at(i);
1679         m->set_method_idnum(i);
1680         m->set_orig_method_idnum(i);
1681       }
1682     }
1683   }
1684 }
1685 
1686 //-----------------------------------------------------------------------------------
1687 // Non-product code unless JVM/TI needs it
1688 
1689 #if !defined(PRODUCT) || INCLUDE_JVMTI
1690 class SignatureTypePrinter : public SignatureTypeNames {
1691  private:
1692   outputStream* _st;
1693   bool _use_separator;
1694 
1695   void type_name(const char* name) {
1696     if (_use_separator) _st->print(", ");
1697     _st->print("%s", name);
1698     _use_separator = true;
1699   }
1700 
1701  public:
1702   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1703     _st = st;
1704     _use_separator = false;
1705   }
1706 
1707   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1708   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1709 };
1710 
1711 
1712 void Method::print_name(outputStream* st) {
1713   Thread *thread = Thread::current();
1714   ResourceMark rm(thread);
1715   st->print("%s ", is_static() ? "static" : "virtual");
1716   if (WizardMode) {
1717     st->print("%s.", method_holder()->internal_name());
1718     name()->print_symbol_on(st);
1719     signature()->print_symbol_on(st);
1720   } else {
1721     SignatureTypePrinter sig(signature(), st);
1722     sig.print_returntype();
1723     st->print(" %s.", method_holder()->internal_name());
1724     name()->print_symbol_on(st);
1725     st->print("(");
1726     sig.print_parameters();
1727     st->print(")");
1728   }
1729 }
1730 #endif // !PRODUCT || INCLUDE_JVMTI
1731 
1732 
1733 void Method::print_codes_on(outputStream* st) const {
1734   print_codes_on(0, code_size(), st);
1735 }
1736 
1737 void Method::print_codes_on(int from, int to, outputStream* st) const {
1738   Thread *thread = Thread::current();
1739   ResourceMark rm(thread);
1740   methodHandle mh (thread, (Method*)this);
1741   BytecodeStream s(mh);
1742   s.set_interval(from, to);
1743   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1744   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1745 }
1746 
1747 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1748   _bci = 0;
1749   _line = 0;
1750 };
1751 
1752 bool CompressedLineNumberReadStream::read_pair() {
1753   jubyte next = read_byte();
1754   // Check for terminator
1755   if (next == 0) return false;
1756   if (next == 0xFF) {
1757     // Escape character, regular compression used
1758     _bci  += read_signed_int();
1759     _line += read_signed_int();
1760   } else {
1761     // Single byte compression used
1762     _bci  += next >> 3;
1763     _line += next & 0x7;
1764   }
1765   return true;
1766 }
1767 
1768 #if INCLUDE_JVMTI
1769 
1770 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1771   BreakpointInfo* bp = method_holder()->breakpoints();
1772   for (; bp != NULL; bp = bp->next()) {
1773     if (bp->match(this, bci)) {
1774       return bp->orig_bytecode();
1775     }
1776   }
1777   {
1778     ResourceMark rm;
1779     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1780   }
1781   return Bytecodes::_shouldnotreachhere;
1782 }
1783 
1784 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1785   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1786   BreakpointInfo* bp = method_holder()->breakpoints();
1787   for (; bp != NULL; bp = bp->next()) {
1788     if (bp->match(this, bci)) {
1789       bp->set_orig_bytecode(code);
1790       // and continue, in case there is more than one
1791     }
1792   }
1793 }
1794 
1795 void Method::set_breakpoint(int bci) {
1796   InstanceKlass* ik = method_holder();
1797   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1798   bp->set_next(ik->breakpoints());
1799   ik->set_breakpoints(bp);
1800   // do this last:
1801   bp->set(this);
1802 }
1803 
1804 static void clear_matches(Method* m, int bci) {
1805   InstanceKlass* ik = m->method_holder();
1806   BreakpointInfo* prev_bp = NULL;
1807   BreakpointInfo* next_bp;
1808   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1809     next_bp = bp->next();
1810     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1811     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1812       // do this first:
1813       bp->clear(m);
1814       // unhook it
1815       if (prev_bp != NULL)
1816         prev_bp->set_next(next_bp);
1817       else
1818         ik->set_breakpoints(next_bp);
1819       delete bp;
1820       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1821       // at same location. So we have multiple matching (method_index and bci)
1822       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1823       // breakpoint for clear_breakpoint request and keep all other method versions
1824       // BreakpointInfo for future clear_breakpoint request.
1825       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1826       // which is being called when class is unloaded. We delete all the Breakpoint
1827       // information for all versions of method. We may not correctly restore the original
1828       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1829       // so these methods won't be used anymore.
1830       if (bci >= 0) {
1831         break;
1832       }
1833     } else {
1834       // This one is a keeper.
1835       prev_bp = bp;
1836     }
1837   }
1838 }
1839 
1840 void Method::clear_breakpoint(int bci) {
1841   assert(bci >= 0, "");
1842   clear_matches(this, bci);
1843 }
1844 
1845 void Method::clear_all_breakpoints() {
1846   clear_matches(this, -1);
1847 }
1848 
1849 #endif // INCLUDE_JVMTI
1850 
1851 int Method::invocation_count() {
1852   MethodCounters *mcs = method_counters();
1853   if (TieredCompilation) {
1854     MethodData* const mdo = method_data();
1855     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1856         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1857       return InvocationCounter::count_limit;
1858     } else {
1859       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1860              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1861     }
1862   } else {
1863     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1864   }
1865 }
1866 
1867 int Method::backedge_count() {
1868   MethodCounters *mcs = method_counters();
1869   if (TieredCompilation) {
1870     MethodData* const mdo = method_data();
1871     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1872         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1873       return InvocationCounter::count_limit;
1874     } else {
1875       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1876              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1877     }
1878   } else {
1879     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1880   }
1881 }
1882 
1883 int Method::highest_comp_level() const {
1884   const MethodCounters* mcs = method_counters();
1885   if (mcs != NULL) {
1886     return mcs->highest_comp_level();
1887   } else {
1888     return CompLevel_none;
1889   }
1890 }
1891 
1892 int Method::highest_osr_comp_level() const {
1893   const MethodCounters* mcs = method_counters();
1894   if (mcs != NULL) {
1895     return mcs->highest_osr_comp_level();
1896   } else {
1897     return CompLevel_none;
1898   }
1899 }
1900 
1901 void Method::set_highest_comp_level(int level) {
1902   MethodCounters* mcs = method_counters();
1903   if (mcs != NULL) {
1904     mcs->set_highest_comp_level(level);
1905   }
1906 }
1907 
1908 void Method::set_highest_osr_comp_level(int level) {
1909   MethodCounters* mcs = method_counters();
1910   if (mcs != NULL) {
1911     mcs->set_highest_osr_comp_level(level);
1912   }
1913 }
1914 
1915 #if INCLUDE_JVMTI
1916 
1917 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1918   _bci = bci;
1919   _name_index = m->name_index();
1920   _signature_index = m->signature_index();
1921   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1922   if (_orig_bytecode == Bytecodes::_breakpoint)
1923     _orig_bytecode = m->orig_bytecode_at(_bci);
1924   _next = NULL;
1925 }
1926 
1927 void BreakpointInfo::set(Method* method) {
1928 #ifdef ASSERT
1929   {
1930     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1931     if (code == Bytecodes::_breakpoint)
1932       code = method->orig_bytecode_at(_bci);
1933     assert(orig_bytecode() == code, "original bytecode must be the same");
1934   }
1935 #endif
1936   Thread *thread = Thread::current();
1937   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1938   method->incr_number_of_breakpoints(thread);
1939   {
1940     // Deoptimize all dependents on this method
1941     HandleMark hm(thread);
1942     methodHandle mh(thread, method);
1943     CodeCache::flush_dependents_on_method(mh);
1944   }
1945 }
1946 
1947 void BreakpointInfo::clear(Method* method) {
1948   *method->bcp_from(_bci) = orig_bytecode();
1949   assert(method->number_of_breakpoints() > 0, "must not go negative");
1950   method->decr_number_of_breakpoints(Thread::current());
1951 }
1952 
1953 #endif // INCLUDE_JVMTI
1954 
1955 // jmethodID handling
1956 
1957 // This is a block allocating object, sort of like JNIHandleBlock, only a
1958 // lot simpler.
1959 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1960 // never get rid of it.
1961 
1962 static const int min_block_size = 8;
1963 
1964 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1965   friend class JNIMethodBlock;
1966   Method**        _methods;
1967   int             _number_of_methods;
1968   int             _top;
1969   JNIMethodBlockNode* _next;
1970 
1971  public:
1972 
1973   JNIMethodBlockNode(int num_methods = min_block_size);
1974 
1975   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1976 
1977   void ensure_methods(int num_addl_methods) {
1978     if (_top < _number_of_methods) {
1979       num_addl_methods -= _number_of_methods - _top;
1980       if (num_addl_methods <= 0) {
1981         return;
1982       }
1983     }
1984     if (_next == NULL) {
1985       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1986     } else {
1987       _next->ensure_methods(num_addl_methods);
1988     }
1989   }
1990 };
1991 
1992 class JNIMethodBlock : public CHeapObj<mtClass> {
1993   JNIMethodBlockNode _head;
1994   JNIMethodBlockNode *_last_free;
1995  public:
1996   static Method* const _free_method;
1997 
1998   JNIMethodBlock(int initial_capacity = min_block_size)
1999       : _head(initial_capacity), _last_free(&_head) {}
2000 
2001   void ensure_methods(int num_addl_methods) {
2002     _last_free->ensure_methods(num_addl_methods);
2003   }
2004 
2005   Method** add_method(Method* m) {
2006     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2007       if (b->_top < b->_number_of_methods) {
2008         // top points to the next free entry.
2009         int i = b->_top;
2010         b->_methods[i] = m;
2011         b->_top++;
2012         _last_free = b;
2013         return &(b->_methods[i]);
2014       } else if (b->_top == b->_number_of_methods) {
2015         // if the next free entry ran off the block see if there's a free entry
2016         for (int i = 0; i < b->_number_of_methods; i++) {
2017           if (b->_methods[i] == _free_method) {
2018             b->_methods[i] = m;
2019             _last_free = b;
2020             return &(b->_methods[i]);
2021           }
2022         }
2023         // Only check each block once for frees.  They're very unlikely.
2024         // Increment top past the end of the block.
2025         b->_top++;
2026       }
2027       // need to allocate a next block.
2028       if (b->_next == NULL) {
2029         b->_next = _last_free = new JNIMethodBlockNode();
2030       }
2031     }
2032     guarantee(false, "Should always allocate a free block");
2033     return NULL;
2034   }
2035 
2036   bool contains(Method** m) {
2037     if (m == NULL) return false;
2038     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2039       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2040         // This is a bit of extra checking, for two reasons.  One is
2041         // that contains() deals with pointers that are passed in by
2042         // JNI code, so making sure that the pointer is aligned
2043         // correctly is valuable.  The other is that <= and > are
2044         // technically not defined on pointers, so the if guard can
2045         // pass spuriously; no modern compiler is likely to make that
2046         // a problem, though (and if one did, the guard could also
2047         // fail spuriously, which would be bad).
2048         ptrdiff_t idx = m - b->_methods;
2049         if (b->_methods + idx == m) {
2050           return true;
2051         }
2052       }
2053     }
2054     return false;  // not found
2055   }
2056 
2057   // Doesn't really destroy it, just marks it as free so it can be reused.
2058   void destroy_method(Method** m) {
2059 #ifdef ASSERT
2060     assert(contains(m), "should be a methodID");
2061 #endif // ASSERT
2062     *m = _free_method;
2063   }
2064 
2065   // During class unloading the methods are cleared, which is different
2066   // than freed.
2067   void clear_all_methods() {
2068     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2069       for (int i = 0; i< b->_number_of_methods; i++) {
2070         b->_methods[i] = NULL;
2071       }
2072     }
2073   }
2074 #ifndef PRODUCT
2075   int count_methods() {
2076     // count all allocated methods
2077     int count = 0;
2078     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2079       for (int i = 0; i< b->_number_of_methods; i++) {
2080         if (b->_methods[i] != _free_method) count++;
2081       }
2082     }
2083     return count;
2084   }
2085 #endif // PRODUCT
2086 };
2087 
2088 // Something that can't be mistaken for an address or a markWord
2089 Method* const JNIMethodBlock::_free_method = (Method*)55;
2090 
2091 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2092   _number_of_methods = MAX2(num_methods, min_block_size);
2093   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2094   for (int i = 0; i < _number_of_methods; i++) {
2095     _methods[i] = JNIMethodBlock::_free_method;
2096   }
2097 }
2098 
2099 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2100   ClassLoaderData* cld = loader_data;
2101   if (!SafepointSynchronize::is_at_safepoint()) {
2102     // Have to add jmethod_ids() to class loader data thread-safely.
2103     // Also have to add the method to the list safely, which the cld lock
2104     // protects as well.
2105     MutexLocker ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2106     if (cld->jmethod_ids() == NULL) {
2107       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2108     } else {
2109       cld->jmethod_ids()->ensure_methods(capacity);
2110     }
2111   } else {
2112     // At safepoint, we are single threaded and can set this.
2113     if (cld->jmethod_ids() == NULL) {
2114       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2115     } else {
2116       cld->jmethod_ids()->ensure_methods(capacity);
2117     }
2118   }
2119 }
2120 
2121 // Add a method id to the jmethod_ids
2122 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2123   ClassLoaderData* cld = loader_data;
2124 
2125   if (!SafepointSynchronize::is_at_safepoint()) {
2126     // Have to add jmethod_ids() to class loader data thread-safely.
2127     // Also have to add the method to the list safely, which the cld lock
2128     // protects as well.
2129     MutexLocker ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2130     if (cld->jmethod_ids() == NULL) {
2131       cld->set_jmethod_ids(new JNIMethodBlock());
2132     }
2133     // jmethodID is a pointer to Method*
2134     return (jmethodID)cld->jmethod_ids()->add_method(m);
2135   } else {
2136     // At safepoint, we are single threaded and can set this.
2137     if (cld->jmethod_ids() == NULL) {
2138       cld->set_jmethod_ids(new JNIMethodBlock());
2139     }
2140     // jmethodID is a pointer to Method*
2141     return (jmethodID)cld->jmethod_ids()->add_method(m);
2142   }
2143 }
2144 
2145 // Mark a jmethodID as free.  This is called when there is a data race in
2146 // InstanceKlass while creating the jmethodID cache.
2147 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2148   ClassLoaderData* cld = loader_data;
2149   Method** ptr = (Method**)m;
2150   assert(cld->jmethod_ids() != NULL, "should have method handles");
2151   cld->jmethod_ids()->destroy_method(ptr);
2152 }
2153 
2154 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2155   // Can't assert the method_holder is the same because the new method has the
2156   // scratch method holder.
2157   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2158            == new_method->method_holder()->class_loader() ||
2159            new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2160          "changing to a different class loader");
2161   // Just change the method in place, jmethodID pointer doesn't change.
2162   *((Method**)jmid) = new_method;
2163 }
2164 
2165 bool Method::is_method_id(jmethodID mid) {
2166   Method* m = resolve_jmethod_id(mid);
2167   assert(m != NULL, "should be called with non-null method");
2168   InstanceKlass* ik = m->method_holder();
2169   ClassLoaderData* cld = ik->class_loader_data();
2170   if (cld->jmethod_ids() == NULL) return false;
2171   return (cld->jmethod_ids()->contains((Method**)mid));
2172 }
2173 
2174 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2175   if (mid == NULL) return NULL;
2176   Method* o = resolve_jmethod_id(mid);
2177   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2178     return NULL;
2179   }
2180   return o;
2181 };
2182 
2183 void Method::set_on_stack(const bool value) {
2184   // Set both the method itself and its constant pool.  The constant pool
2185   // on stack means some method referring to it is also on the stack.
2186   constants()->set_on_stack(value);
2187 
2188   bool already_set = on_stack();
2189   _access_flags.set_on_stack(value);
2190   if (value && !already_set) {
2191     MetadataOnStackMark::record(this);
2192   }
2193   assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2194          "emcp methods cannot run after emcp bit is cleared");
2195 }
2196 
2197 // Called when the class loader is unloaded to make all methods weak.
2198 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2199   loader_data->jmethod_ids()->clear_all_methods();
2200 }
2201 
2202 bool Method::has_method_vptr(const void* ptr) {
2203   Method m;
2204   // This assumes that the vtbl pointer is the first word of a C++ object.
2205   return dereference_vptr(&m) == dereference_vptr(ptr);
2206 }
2207 
2208 // Check that this pointer is valid by checking that the vtbl pointer matches
2209 bool Method::is_valid_method(const Method* m) {
2210   if (m == NULL) {
2211     return false;
2212   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2213     // Quick sanity check on pointer.
2214     return false;
2215   } else if (m->is_shared()) {
2216     return MetaspaceShared::is_valid_shared_method(m);
2217   } else if (Metaspace::contains_non_shared(m)) {
2218     return has_method_vptr((const void*)m);
2219   } else {
2220     return false;
2221   }
2222 }
2223 
2224 #ifndef PRODUCT
2225 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2226   out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2227 }
2228 #endif // PRODUCT
2229 
2230 
2231 // Printing
2232 
2233 #ifndef PRODUCT
2234 
2235 void Method::print_on(outputStream* st) const {
2236   ResourceMark rm;
2237   assert(is_method(), "must be method");
2238   st->print_cr("%s", internal_name());
2239   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2240   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2241   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2242   constants()->print_value_on(st); st->cr();
2243   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2244   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2245   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2246   st->print_cr(" - max stack:         %d",   max_stack());
2247   st->print_cr(" - max locals:        %d",   max_locals());
2248   st->print_cr(" - size of params:    %d",   size_of_parameters());
2249   st->print_cr(" - method size:       %d",   method_size());
2250   if (intrinsic_id() != vmIntrinsics::_none)
2251     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2252   if (highest_comp_level() != CompLevel_none)
2253     st->print_cr(" - highest level:     %d", highest_comp_level());
2254   st->print_cr(" - vtable index:      %d",   _vtable_index);
2255   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2256   st->print(   " - adapters:          ");
2257   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2258   if (a == NULL)
2259     st->print_cr(INTPTR_FORMAT, p2i(a));
2260   else
2261     a->print_adapter_on(st);
2262   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2263   st->print_cr(" - code size:         %d",   code_size());
2264   if (code_size() != 0) {
2265     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2266     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2267   }
2268   if (method_data() != NULL) {
2269     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2270   }
2271   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2272   if (checked_exceptions_length() > 0) {
2273     CheckedExceptionElement* table = checked_exceptions_start();
2274     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2275     if (Verbose) {
2276       for (int i = 0; i < checked_exceptions_length(); i++) {
2277         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2278       }
2279     }
2280   }
2281   if (has_linenumber_table()) {
2282     u_char* table = compressed_linenumber_table();
2283     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2284     if (Verbose) {
2285       CompressedLineNumberReadStream stream(table);
2286       while (stream.read_pair()) {
2287         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2288       }
2289     }
2290   }
2291   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2292   if (localvariable_table_length() > 0) {
2293     LocalVariableTableElement* table = localvariable_table_start();
2294     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2295     if (Verbose) {
2296       for (int i = 0; i < localvariable_table_length(); i++) {
2297         int bci = table[i].start_bci;
2298         int len = table[i].length;
2299         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2300         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2301         int slot = table[i].slot;
2302         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2303       }
2304     }
2305   }
2306   if (code() != NULL) {
2307     st->print   (" - compiled code: ");
2308     code()->print_value_on(st);
2309   }
2310   if (is_native()) {
2311     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2312     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2313   }
2314 }
2315 
2316 void Method::print_linkage_flags(outputStream* st) {
2317   access_flags().print_on(st);
2318   if (is_default_method()) {
2319     st->print("default ");
2320   }
2321   if (is_overpass()) {
2322     st->print("overpass ");
2323   }
2324 }
2325 #endif //PRODUCT
2326 
2327 void Method::print_value_on(outputStream* st) const {
2328   assert(is_method(), "must be method");
2329   st->print("%s", internal_name());
2330   print_address_on(st);
2331   st->print(" ");
2332   name()->print_value_on(st);
2333   st->print(" ");
2334   signature()->print_value_on(st);
2335   st->print(" in ");
2336   method_holder()->print_value_on(st);
2337   if (WizardMode) st->print("#%d", _vtable_index);
2338   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2339   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2340 }
2341 
2342 #if INCLUDE_SERVICES
2343 // Size Statistics
2344 void Method::collect_statistics(KlassSizeStats *sz) const {
2345   int mysize = sz->count(this);
2346   sz->_method_bytes += mysize;
2347   sz->_method_all_bytes += mysize;
2348   sz->_rw_bytes += mysize;
2349 
2350   if (constMethod()) {
2351     constMethod()->collect_statistics(sz);
2352   }
2353   if (method_data()) {
2354     method_data()->collect_statistics(sz);
2355   }
2356 }
2357 #endif // INCLUDE_SERVICES
2358 
2359 // LogTouchedMethods and PrintTouchedMethods
2360 
2361 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2362 // the Method may be garbage collected. Let's roll our own hash table.
2363 class TouchedMethodRecord : CHeapObj<mtTracing> {
2364 public:
2365   // It's OK to store Symbols here because they will NOT be GC'ed if
2366   // LogTouchedMethods is enabled.
2367   TouchedMethodRecord* _next;
2368   Symbol* _class_name;
2369   Symbol* _method_name;
2370   Symbol* _method_signature;
2371 };
2372 
2373 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2374 static TouchedMethodRecord** _touched_method_table = NULL;
2375 
2376 void Method::log_touched(TRAPS) {
2377 
2378   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2379   Symbol* my_class = klass_name();
2380   Symbol* my_name  = name();
2381   Symbol* my_sig   = signature();
2382 
2383   unsigned int hash = my_class->identity_hash() +
2384                       my_name->identity_hash() +
2385                       my_sig->identity_hash();
2386   juint index = juint(hash) % table_size;
2387 
2388   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2389   if (_touched_method_table == NULL) {
2390     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2391                                               mtTracing, CURRENT_PC);
2392     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2393   }
2394 
2395   TouchedMethodRecord* ptr = _touched_method_table[index];
2396   while (ptr) {
2397     if (ptr->_class_name       == my_class &&
2398         ptr->_method_name      == my_name &&
2399         ptr->_method_signature == my_sig) {
2400       return;
2401     }
2402     if (ptr->_next == NULL) break;
2403     ptr = ptr->_next;
2404   }
2405   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2406   my_class->increment_refcount();
2407   my_name->increment_refcount();
2408   my_sig->increment_refcount();
2409   nptr->_class_name         = my_class;
2410   nptr->_method_name        = my_name;
2411   nptr->_method_signature   = my_sig;
2412   nptr->_next               = NULL;
2413 
2414   if (ptr == NULL) {
2415     // first
2416     _touched_method_table[index] = nptr;
2417   } else {
2418     ptr->_next = nptr;
2419   }
2420 }
2421 
2422 void Method::print_touched_methods(outputStream* out) {
2423   MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2424   out->print_cr("# Method::print_touched_methods version 1");
2425   if (_touched_method_table) {
2426     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2427       TouchedMethodRecord* ptr = _touched_method_table[i];
2428       while(ptr) {
2429         ptr->_class_name->print_symbol_on(out);       out->print(".");
2430         ptr->_method_name->print_symbol_on(out);      out->print(":");
2431         ptr->_method_signature->print_symbol_on(out); out->cr();
2432         ptr = ptr->_next;
2433       }
2434     }
2435   }
2436 }
2437 
2438 // Verification
2439 
2440 void Method::verify_on(outputStream* st) {
2441   guarantee(is_method(), "object must be method");
2442   guarantee(constants()->is_constantPool(), "should be constant pool");
2443   MethodData* md = method_data();
2444   guarantee(md == NULL ||
2445       md->is_methodData(), "should be method data");
2446 }
--- EOF ---