1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/debugInfoRec.hpp"
  29 #include "gc_interface/collectedHeap.inline.hpp"
  30 #include "interpreter/bytecodeStream.hpp"
  31 #include "interpreter/bytecodeTracer.hpp"
  32 #include "interpreter/bytecodes.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "memory/gcLocker.hpp"
  36 #include "memory/generation.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/oopFactory.hpp"
  40 #include "oops/constMethod.hpp"
  41 #include "oops/methodData.hpp"
  42 #include "oops/method.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "oops/symbol.hpp"
  45 #include "prims/jvmtiExport.hpp"
  46 #include "prims/methodHandles.hpp"
  47 #include "prims/nativeLookup.hpp"
  48 #include "runtime/arguments.hpp"
  49 #include "runtime/compilationPolicy.hpp"
  50 #include "runtime/frame.inline.hpp"
  51 #include "runtime/handles.inline.hpp"
  52 #include "runtime/orderAccess.inline.hpp"
  53 #include "runtime/relocator.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "utilities/quickSort.hpp"
  57 #include "utilities/xmlstream.hpp"
  58 
  59 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  60 
  61 // Implementation of Method
  62 
  63 Method* Method::allocate(ClassLoaderData* loader_data,
  64                          int byte_code_size,
  65                          AccessFlags access_flags,
  66                          InlineTableSizes* sizes,
  67                          ConstMethod::MethodType method_type,
  68                          TRAPS) {
  69   assert(!access_flags.is_native() || byte_code_size == 0,
  70          "native methods should not contain byte codes");
  71   ConstMethod* cm = ConstMethod::allocate(loader_data,
  72                                           byte_code_size,
  73                                           sizes,
  74                                           method_type,
  75                                           CHECK_NULL);
  76 
  77   int size = Method::size(access_flags.is_native());
  78 
  79   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  80 }
  81 
  82 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  83   No_Safepoint_Verifier no_safepoint;
  84   set_constMethod(xconst);
  85   set_access_flags(access_flags);
  86   set_method_size(size);
  87 #ifdef CC_INTERP
  88   set_result_index(T_VOID);
  89 #endif
  90   set_intrinsic_id(vmIntrinsics::_none);
  91   set_jfr_towrite(false);
  92   set_force_inline(false);
  93   set_hidden(false);
  94   set_dont_inline(false);
  95   set_method_data(NULL);
  96   set_method_counters(NULL);
  97   set_vtable_index(Method::garbage_vtable_index);
  98 
  99   // Fix and bury in Method*
 100   set_interpreter_entry(NULL); // sets i2i entry and from_int
 101   set_adapter_entry(NULL);
 102   clear_code(); // from_c/from_i get set to c2i/i2i
 103 
 104   if (access_flags.is_native()) {
 105     clear_native_function();
 106     set_signature_handler(NULL);
 107   }
 108 
 109   NOT_PRODUCT(set_compiled_invocation_count(0);)
 110 }
 111 
 112 // Release Method*.  The nmethod will be gone when we get here because
 113 // we've walked the code cache.
 114 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 115   MetadataFactory::free_metadata(loader_data, constMethod());
 116   set_constMethod(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_data());
 118   set_method_data(NULL);
 119   MetadataFactory::free_metadata(loader_data, method_counters());
 120   set_method_counters(NULL);
 121   // The nmethod will be gone when we get here.
 122   if (code() != NULL) _code = NULL;
 123 }
 124 
 125 address Method::get_i2c_entry() {
 126   assert(_adapter != NULL, "must have");
 127   return _adapter->get_i2c_entry();
 128 }
 129 
 130 address Method::get_c2i_entry() {
 131   assert(_adapter != NULL, "must have");
 132   return _adapter->get_c2i_entry();
 133 }
 134 
 135 address Method::get_c2i_unverified_entry() {
 136   assert(_adapter != NULL, "must have");
 137   return _adapter->get_c2i_unverified_entry();
 138 }
 139 
 140 char* Method::name_and_sig_as_C_string() const {
 141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 149   const char* klass_name = klass->external_name();
 150   int klass_name_len  = (int)strlen(klass_name);
 151   int method_name_len = method_name->utf8_length();
 152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 154   strcpy(dest, klass_name);
 155   dest[klass_name_len] = '.';
 156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 158   dest[len] = 0;
 159   return dest;
 160 }
 161 
 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 163   Symbol* klass_name = klass->name();
 164   klass_name->as_klass_external_name(buf, size);
 165   int len = (int)strlen(buf);
 166 
 167   if (len < size - 1) {
 168     buf[len++] = '.';
 169 
 170     method_name->as_C_string(&(buf[len]), size - len);
 171     len = (int)strlen(buf);
 172 
 173     signature->as_C_string(&(buf[len]), size - len);
 174   }
 175 
 176   return buf;
 177 }
 178 
 179 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 181   // access exception table
 182   ExceptionTable table(mh());
 183   int length = table.length();
 184   // iterate through all entries sequentially
 185   constantPoolHandle pool(THREAD, mh->constants());
 186   for (int i = 0; i < length; i ++) {
 187     //reacquire the table in case a GC happened
 188     ExceptionTable table(mh());
 189     int beg_bci = table.start_pc(i);
 190     int end_bci = table.end_pc(i);
 191     assert(beg_bci <= end_bci, "inconsistent exception table");
 192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 193       // exception handler bci range covers throw_bci => investigate further
 194       int handler_bci = table.handler_pc(i);
 195       int klass_index = table.catch_type_index(i);
 196       if (klass_index == 0) {
 197         return handler_bci;
 198       } else if (ex_klass.is_null()) {
 199         return handler_bci;
 200       } else {
 201         // we know the exception class => get the constraint class
 202         // this may require loading of the constraint class; if verification
 203         // fails or some other exception occurs, return handler_bci
 204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 205         KlassHandle klass = KlassHandle(THREAD, k);
 206         assert(klass.not_null(), "klass not loaded");
 207         if (ex_klass->is_subtype_of(klass())) {
 208           return handler_bci;
 209         }
 210       }
 211     }
 212   }
 213 
 214   return -1;
 215 }
 216 
 217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 218 
 219   Thread* myThread    = Thread::current();
 220   methodHandle h_this(myThread, this);
 221 #ifdef ASSERT
 222   bool has_capability = myThread->is_VM_thread() ||
 223                         myThread->is_ConcurrentGC_thread() ||
 224                         myThread->is_GC_task_thread();
 225 
 226   if (!has_capability) {
 227     if (!VerifyStack && !VerifyLastFrame) {
 228       // verify stack calls this outside VM thread
 229       warning("oopmap should only be accessed by the "
 230               "VM, GC task or CMS threads (or during debugging)");
 231       InterpreterOopMap local_mask;
 232       method_holder()->mask_for(h_this, bci, &local_mask);
 233       local_mask.print();
 234     }
 235   }
 236 #endif
 237   method_holder()->mask_for(h_this, bci, mask);
 238   return;
 239 }
 240 
 241 
 242 int Method::bci_from(address bcp) const {
 243   if (is_native() && bcp == 0) {
 244     return 0;
 245   }
 246 #ifdef ASSERT
 247   { ResourceMark rm;
 248   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 249          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 250   }
 251 #endif
 252   return bcp - code_base();
 253 }
 254 
 255 
 256 int Method::validate_bci(int bci) const {
 257   return (bci == 0 || bci < code_size()) ? bci : -1;
 258 }
 259 
 260 // Return bci if it appears to be a valid bcp
 261 // Return -1 otherwise.
 262 // Used by profiling code, when invalid data is a possibility.
 263 // The caller is responsible for validating the Method* itself.
 264 int Method::validate_bci_from_bcp(address bcp) const {
 265   // keep bci as -1 if not a valid bci
 266   int bci = -1;
 267   if (bcp == 0 || bcp == code_base()) {
 268     // code_size() may return 0 and we allow 0 here
 269     // the method may be native
 270     bci = 0;
 271   } else if (contains(bcp)) {
 272     bci = bcp - code_base();
 273   }
 274   // Assert that if we have dodged any asserts, bci is negative.
 275   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 276   return bci;
 277 }
 278 
 279 address Method::bcp_from(int bci) const {
 280   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), err_msg("illegal bci: %d", bci));
 281   address bcp = code_base() + bci;
 282   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 283   return bcp;
 284 }
 285 
 286 address Method::bcp_from(address bcp) const {
 287   if (is_native() && bcp == 0) {
 288     return code_base() + (intptr_t)bcp;
 289   } else {
 290     return bcp;
 291   }
 292 }
 293 
 294 int Method::size(bool is_native) {
 295   // If native, then include pointers for native_function and signature_handler
 296   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 297   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 298   return align_object_size(header_size() + extra_words);
 299 }
 300 
 301 
 302 Symbol* Method::klass_name() const {
 303   Klass* k = method_holder();
 304   assert(k->is_klass(), "must be klass");
 305   InstanceKlass* ik = (InstanceKlass*) k;
 306   return ik->name();
 307 }
 308 
 309 
 310 // Attempt to return method oop to original state.  Clear any pointers
 311 // (to objects outside the shared spaces).  We won't be able to predict
 312 // where they should point in a new JVM.  Further initialize some
 313 // entries now in order allow them to be write protected later.
 314 
 315 void Method::remove_unshareable_info() {
 316   unlink_method();
 317 }
 318 
 319 
 320 bool Method::was_executed_more_than(int n) {
 321   // Invocation counter is reset when the Method* is compiled.
 322   // If the method has compiled code we therefore assume it has
 323   // be excuted more than n times.
 324   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 325     // interpreter doesn't bump invocation counter of trivial methods
 326     // compiler does not bump invocation counter of compiled methods
 327     return true;
 328   }
 329   else if ((method_counters() != NULL &&
 330             method_counters()->invocation_counter()->carry()) ||
 331            (method_data() != NULL &&
 332             method_data()->invocation_counter()->carry())) {
 333     // The carry bit is set when the counter overflows and causes
 334     // a compilation to occur.  We don't know how many times
 335     // the counter has been reset, so we simply assume it has
 336     // been executed more than n times.
 337     return true;
 338   } else {
 339     return invocation_count() > n;
 340   }
 341 }
 342 
 343 void Method::print_invocation_count() {
 344   if (is_static()) tty->print("static ");
 345   if (is_final()) tty->print("final ");
 346   if (is_synchronized()) tty->print("synchronized ");
 347   if (is_native()) tty->print("native ");
 348   tty->print("%s::", method_holder()->external_name());
 349   name()->print_symbol_on(tty);
 350   signature()->print_symbol_on(tty);
 351 
 352   if (WizardMode) {
 353     // dump the size of the byte codes
 354     tty->print(" {%d}", code_size());
 355   }
 356   tty->cr();
 357 
 358   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 359   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 360   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 361 #ifndef PRODUCT
 362   if (CountCompiledCalls) {
 363     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 364   }
 365 #endif
 366 }
 367 
 368 // Build a MethodData* object to hold information about this method
 369 // collected in the interpreter.
 370 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 371   // Do not profile method if current thread holds the pending list lock,
 372   // which avoids deadlock for acquiring the MethodData_lock.
 373   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 374     return;
 375   }
 376 
 377   // Grab a lock here to prevent multiple
 378   // MethodData*s from being created.
 379   MutexLocker ml(MethodData_lock, THREAD);
 380   if (method->method_data() == NULL) {
 381     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 382     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 383     method->set_method_data(method_data);
 384     if (PrintMethodData && (Verbose || WizardMode)) {
 385       ResourceMark rm(THREAD);
 386       tty->print("build_interpreter_method_data for ");
 387       method->print_name(tty);
 388       tty->cr();
 389       // At the end of the run, the MDO, full of data, will be dumped.
 390     }
 391   }
 392 }
 393 
 394 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 395   methodHandle mh(m);
 396   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
 397   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
 398   if (mh->method_counters() == NULL) {
 399     mh->set_method_counters(counters);
 400   } else {
 401     MetadataFactory::free_metadata(loader_data, counters);
 402   }
 403   return mh->method_counters();
 404 }
 405 
 406 void Method::cleanup_inline_caches() {
 407   // The current system doesn't use inline caches in the interpreter
 408   // => nothing to do (keep this method around for future use)
 409 }
 410 
 411 
 412 int Method::extra_stack_words() {
 413   // not an inline function, to avoid a header dependency on Interpreter
 414   return extra_stack_entries() * Interpreter::stackElementSize;
 415 }
 416 
 417 
 418 void Method::compute_size_of_parameters(Thread *thread) {
 419   ArgumentSizeComputer asc(signature());
 420   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 421 }
 422 
 423 #ifdef CC_INTERP
 424 void Method::set_result_index(BasicType type)          {
 425   _result_index = Interpreter::BasicType_as_index(type);
 426 }
 427 #endif
 428 
 429 BasicType Method::result_type() const {
 430   ResultTypeFinder rtf(signature());
 431   return rtf.type();
 432 }
 433 
 434 
 435 bool Method::is_empty_method() const {
 436   return  code_size() == 1
 437       && *code_base() == Bytecodes::_return;
 438 }
 439 
 440 
 441 bool Method::is_vanilla_constructor() const {
 442   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 443   // which only calls the superclass vanilla constructor and possibly does stores of
 444   // zero constants to local fields:
 445   //
 446   //   aload_0
 447   //   invokespecial
 448   //   indexbyte1
 449   //   indexbyte2
 450   //
 451   // followed by an (optional) sequence of:
 452   //
 453   //   aload_0
 454   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 455   //   putfield
 456   //   indexbyte1
 457   //   indexbyte2
 458   //
 459   // followed by:
 460   //
 461   //   return
 462 
 463   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 464   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 465   int size = code_size();
 466   // Check if size match
 467   if (size == 0 || size % 5 != 0) return false;
 468   address cb = code_base();
 469   int last = size - 1;
 470   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 471     // Does not call superclass default constructor
 472     return false;
 473   }
 474   // Check optional sequence
 475   for (int i = 4; i < last; i += 5) {
 476     if (cb[i] != Bytecodes::_aload_0) return false;
 477     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 478     if (cb[i+2] != Bytecodes::_putfield) return false;
 479   }
 480   return true;
 481 }
 482 
 483 
 484 bool Method::compute_has_loops_flag() {
 485   BytecodeStream bcs(this);
 486   Bytecodes::Code bc;
 487 
 488   while ((bc = bcs.next()) >= 0) {
 489     switch( bc ) {
 490       case Bytecodes::_ifeq:
 491       case Bytecodes::_ifnull:
 492       case Bytecodes::_iflt:
 493       case Bytecodes::_ifle:
 494       case Bytecodes::_ifne:
 495       case Bytecodes::_ifnonnull:
 496       case Bytecodes::_ifgt:
 497       case Bytecodes::_ifge:
 498       case Bytecodes::_if_icmpeq:
 499       case Bytecodes::_if_icmpne:
 500       case Bytecodes::_if_icmplt:
 501       case Bytecodes::_if_icmpgt:
 502       case Bytecodes::_if_icmple:
 503       case Bytecodes::_if_icmpge:
 504       case Bytecodes::_if_acmpeq:
 505       case Bytecodes::_if_acmpne:
 506       case Bytecodes::_goto:
 507       case Bytecodes::_jsr:
 508         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 509         break;
 510 
 511       case Bytecodes::_goto_w:
 512       case Bytecodes::_jsr_w:
 513         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 514         break;
 515     }
 516   }
 517   _access_flags.set_loops_flag_init();
 518   return _access_flags.has_loops();
 519 }
 520 
 521 bool Method::is_final_method(AccessFlags class_access_flags) const {
 522   // or "does_not_require_vtable_entry"
 523   // default method or overpass can occur, is not final (reuses vtable entry)
 524   // private methods get vtable entries for backward class compatibility.
 525   if (is_overpass() || is_default_method())  return false;
 526   return is_final() || class_access_flags.is_final();
 527 }
 528 
 529 bool Method::is_final_method() const {
 530   return is_final_method(method_holder()->access_flags());
 531 }
 532 
 533 bool Method::is_default_method() const {
 534   if (method_holder() != NULL &&
 535       method_holder()->is_interface() &&
 536       !is_abstract()) {
 537     return true;
 538   } else {
 539     return false;
 540   }
 541 }
 542 
 543 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 544   if (is_final_method(class_access_flags))  return true;
 545 #ifdef ASSERT
 546   ResourceMark rm;
 547   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 548   if (class_access_flags.is_interface()) {
 549       assert(is_nonv == is_static(), err_msg("is_nonv=%s", name_and_sig_as_C_string()));
 550   }
 551 #endif
 552   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 553   return vtable_index() == nonvirtual_vtable_index;
 554 }
 555 
 556 bool Method::can_be_statically_bound() const {
 557   return can_be_statically_bound(method_holder()->access_flags());
 558 }
 559 
 560 bool Method::is_accessor() const {
 561   if (code_size() != 5) return false;
 562   if (size_of_parameters() != 1) return false;
 563   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 564   if (java_code_at(1) != Bytecodes::_getfield) return false;
 565   if (java_code_at(4) != Bytecodes::_areturn &&
 566       java_code_at(4) != Bytecodes::_ireturn ) return false;
 567   return true;
 568 }
 569 
 570 
 571 bool Method::is_initializer() const {
 572   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 573 }
 574 
 575 bool Method::has_valid_initializer_flags() const {
 576   return (is_static() ||
 577           method_holder()->major_version() < 51);
 578 }
 579 
 580 bool Method::is_static_initializer() const {
 581   // For classfiles version 51 or greater, ensure that the clinit method is
 582   // static.  Non-static methods with the name "<clinit>" are not static
 583   // initializers. (older classfiles exempted for backward compatibility)
 584   return name() == vmSymbols::class_initializer_name() &&
 585          has_valid_initializer_flags();
 586 }
 587 
 588 
 589 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 590   int length = method->checked_exceptions_length();
 591   if (length == 0) {  // common case
 592     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 593   } else {
 594     methodHandle h_this(THREAD, method);
 595     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 596     objArrayHandle mirrors (THREAD, m_oop);
 597     for (int i = 0; i < length; i++) {
 598       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 599       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 600       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 601       mirrors->obj_at_put(i, k->java_mirror());
 602     }
 603     return mirrors;
 604   }
 605 };
 606 
 607 
 608 int Method::line_number_from_bci(int bci) const {
 609   if (bci == SynchronizationEntryBCI) bci = 0;
 610   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 611   int best_bci  =  0;
 612   int best_line = -1;
 613 
 614   if (has_linenumber_table()) {
 615     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 616     // Not necessarily sorted and not necessarily one-to-one.
 617     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 618     while (stream.read_pair()) {
 619       if (stream.bci() == bci) {
 620         // perfect match
 621         return stream.line();
 622       } else {
 623         // update best_bci/line
 624         if (stream.bci() < bci && stream.bci() >= best_bci) {
 625           best_bci  = stream.bci();
 626           best_line = stream.line();
 627         }
 628       }
 629     }
 630   }
 631   return best_line;
 632 }
 633 
 634 
 635 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 636   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 637     Thread *thread = Thread::current();
 638     Symbol* klass_name = constants()->klass_name_at(klass_index);
 639     Handle loader(thread, method_holder()->class_loader());
 640     Handle prot  (thread, method_holder()->protection_domain());
 641     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 642   } else {
 643     return true;
 644   }
 645 }
 646 
 647 
 648 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 649   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 650   if (must_be_resolved) {
 651     // Make sure klass is resolved in constantpool.
 652     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 653   }
 654   return is_klass_loaded_by_klass_index(klass_index);
 655 }
 656 
 657 
 658 void Method::set_native_function(address function, bool post_event_flag) {
 659   assert(function != NULL, "use clear_native_function to unregister natives");
 660   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 661   address* native_function = native_function_addr();
 662 
 663   // We can see racers trying to place the same native function into place. Once
 664   // is plenty.
 665   address current = *native_function;
 666   if (current == function) return;
 667   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 668       function != NULL) {
 669     // native_method_throw_unsatisfied_link_error_entry() should only
 670     // be passed when post_event_flag is false.
 671     assert(function !=
 672       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 673       "post_event_flag mis-match");
 674 
 675     // post the bind event, and possible change the bind function
 676     JvmtiExport::post_native_method_bind(this, &function);
 677   }
 678   *native_function = function;
 679   // This function can be called more than once. We must make sure that we always
 680   // use the latest registered method -> check if a stub already has been generated.
 681   // If so, we have to make it not_entrant.
 682   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 683   if (nm != NULL) {
 684     nm->make_not_entrant();
 685   }
 686 }
 687 
 688 
 689 bool Method::has_native_function() const {
 690   if (is_method_handle_intrinsic())
 691     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 692   address func = native_function();
 693   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 694 }
 695 
 696 
 697 void Method::clear_native_function() {
 698   // Note: is_method_handle_intrinsic() is allowed here.
 699   set_native_function(
 700     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 701     !native_bind_event_is_interesting);
 702   clear_code();
 703 }
 704 
 705 address Method::critical_native_function() {
 706   methodHandle mh(this);
 707   return NativeLookup::lookup_critical_entry(mh);
 708 }
 709 
 710 
 711 void Method::set_signature_handler(address handler) {
 712   address* signature_handler =  signature_handler_addr();
 713   *signature_handler = handler;
 714 }
 715 
 716 
 717 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 718   if (PrintCompilation && report) {
 719     ttyLocker ttyl;
 720     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 721     if (comp_level == CompLevel_all) {
 722       tty->print("all levels ");
 723     } else {
 724       tty->print("levels ");
 725       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 726         tty->print("%d ", i);
 727       }
 728     }
 729     this->print_short_name(tty);
 730     int size = this->code_size();
 731     if (size > 0) {
 732       tty->print(" (%d bytes)", size);
 733     }
 734     if (reason != NULL) {
 735       tty->print("   %s", reason);
 736     }
 737     tty->cr();
 738   }
 739   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 740     ttyLocker ttyl;
 741     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 742                      os::current_thread_id(), is_osr, comp_level);
 743     if (reason != NULL) {
 744       xtty->print(" reason=\'%s\'", reason);
 745     }
 746     xtty->method(this);
 747     xtty->stamp();
 748     xtty->end_elem();
 749   }
 750 }
 751 
 752 bool Method::is_always_compilable() const {
 753   // Generated adapters must be compiled
 754   if (is_method_handle_intrinsic() && is_synthetic()) {
 755     assert(!is_not_c1_compilable(), "sanity check");
 756     assert(!is_not_c2_compilable(), "sanity check");
 757     return true;
 758   }
 759 
 760   return false;
 761 }
 762 
 763 bool Method::is_not_compilable(int comp_level) const {
 764   if (number_of_breakpoints() > 0)
 765     return true;
 766   if (is_always_compilable())
 767     return false;
 768   if (comp_level == CompLevel_any)
 769     return is_not_c1_compilable() || is_not_c2_compilable();
 770   if (is_c1_compile(comp_level))
 771     return is_not_c1_compilable();
 772   if (is_c2_compile(comp_level))
 773     return is_not_c2_compilable();
 774   return false;
 775 }
 776 
 777 // call this when compiler finds that this method is not compilable
 778 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 779   if (is_always_compilable()) {
 780     // Don't mark a method which should be always compilable
 781     return;
 782   }
 783   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 784   if (comp_level == CompLevel_all) {
 785     set_not_c1_compilable();
 786     set_not_c2_compilable();
 787   } else {
 788     if (is_c1_compile(comp_level))
 789       set_not_c1_compilable();
 790     if (is_c2_compile(comp_level))
 791       set_not_c2_compilable();
 792   }
 793   CompilationPolicy::policy()->disable_compilation(this);
 794   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 795 }
 796 
 797 bool Method::is_not_osr_compilable(int comp_level) const {
 798   if (is_not_compilable(comp_level))
 799     return true;
 800   if (comp_level == CompLevel_any)
 801     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 802   if (is_c1_compile(comp_level))
 803     return is_not_c1_osr_compilable();
 804   if (is_c2_compile(comp_level))
 805     return is_not_c2_osr_compilable();
 806   return false;
 807 }
 808 
 809 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 810   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 811   if (comp_level == CompLevel_all) {
 812     set_not_c1_osr_compilable();
 813     set_not_c2_osr_compilable();
 814   } else {
 815     if (is_c1_compile(comp_level))
 816       set_not_c1_osr_compilable();
 817     if (is_c2_compile(comp_level))
 818       set_not_c2_osr_compilable();
 819   }
 820   CompilationPolicy::policy()->disable_compilation(this);
 821   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 822 }
 823 
 824 // Revert to using the interpreter and clear out the nmethod
 825 void Method::clear_code() {
 826 
 827   // this may be NULL if c2i adapters have not been made yet
 828   // Only should happen at allocate time.
 829   if (_adapter == NULL) {
 830     _from_compiled_entry    = NULL;
 831   } else {
 832     _from_compiled_entry    = _adapter->get_c2i_entry();
 833   }
 834   OrderAccess::storestore();
 835   _from_interpreted_entry = _i2i_entry;
 836   OrderAccess::storestore();
 837   _code = NULL;
 838 }
 839 
 840 // Called by class data sharing to remove any entry points (which are not shared)
 841 void Method::unlink_method() {
 842   _code = NULL;
 843   _i2i_entry = NULL;
 844   _from_interpreted_entry = NULL;
 845   if (is_native()) {
 846     *native_function_addr() = NULL;
 847     set_signature_handler(NULL);
 848   }
 849   NOT_PRODUCT(set_compiled_invocation_count(0);)
 850   _adapter = NULL;
 851   _from_compiled_entry = NULL;
 852 
 853   // In case of DumpSharedSpaces, _method_data should always be NULL.
 854   //
 855   // During runtime (!DumpSharedSpaces), when we are cleaning a
 856   // shared class that failed to load, this->link_method() may
 857   // have already been called (before an exception happened), so
 858   // this->_method_data may not be NULL.
 859   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 860 
 861   set_method_data(NULL);
 862   set_method_counters(NULL);
 863 }
 864 
 865 // Called when the method_holder is getting linked. Setup entrypoints so the method
 866 // is ready to be called from interpreter, compiler, and vtables.
 867 void Method::link_method(methodHandle h_method, TRAPS) {
 868   // If the code cache is full, we may reenter this function for the
 869   // leftover methods that weren't linked.
 870   if (_i2i_entry != NULL) return;
 871 
 872   assert(_adapter == NULL, "init'd to NULL" );
 873   assert( _code == NULL, "nothing compiled yet" );
 874 
 875   // Setup interpreter entrypoint
 876   assert(this == h_method(), "wrong h_method()" );
 877   address entry = Interpreter::entry_for_method(h_method);
 878   assert(entry != NULL, "interpreter entry must be non-null");
 879   // Sets both _i2i_entry and _from_interpreted_entry
 880   set_interpreter_entry(entry);
 881 
 882   // Don't overwrite already registered native entries.
 883   if (is_native() && !has_native_function()) {
 884     set_native_function(
 885       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 886       !native_bind_event_is_interesting);
 887   }
 888 
 889   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 890   // special handling of vtables.  An alternative is to make adapters more
 891   // lazily by calling make_adapter() from from_compiled_entry() for the
 892   // normal calls.  For vtable calls life gets more complicated.  When a
 893   // call-site goes mega-morphic we need adapters in all methods which can be
 894   // called from the vtable.  We need adapters on such methods that get loaded
 895   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 896   // problem we'll make these lazily later.
 897   (void) make_adapters(h_method, CHECK);
 898 
 899   // ONLY USE the h_method now as make_adapter may have blocked
 900 
 901 }
 902 
 903 address Method::make_adapters(methodHandle mh, TRAPS) {
 904   // Adapters for compiled code are made eagerly here.  They are fairly
 905   // small (generally < 100 bytes) and quick to make (and cached and shared)
 906   // so making them eagerly shouldn't be too expensive.
 907   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 908   if (adapter == NULL ) {
 909     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 910   }
 911 
 912   mh->set_adapter_entry(adapter);
 913   mh->_from_compiled_entry = adapter->get_c2i_entry();
 914   return adapter->get_c2i_entry();
 915 }
 916 
 917 void Method::restore_unshareable_info(TRAPS) {
 918   // Since restore_unshareable_info can be called more than once for a method, don't
 919   // redo any work.   If this field is restored, there is nothing to do.
 920   if (_from_compiled_entry == NULL) {
 921     // restore method's vtable by calling a virtual function
 922     restore_vtable();
 923 
 924     methodHandle mh(THREAD, this);
 925     link_method(mh, CHECK);
 926   }
 927 }
 928 
 929 
 930 // The verified_code_entry() must be called when a invoke is resolved
 931 // on this method.
 932 
 933 // It returns the compiled code entry point, after asserting not null.
 934 // This function is called after potential safepoints so that nmethod
 935 // or adapter that it points to is still live and valid.
 936 // This function must not hit a safepoint!
 937 address Method::verified_code_entry() {
 938   debug_only(No_Safepoint_Verifier nsv;)
 939   assert(_from_compiled_entry != NULL, "must be set");
 940   return _from_compiled_entry;
 941 }
 942 
 943 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 944 // (could be racing a deopt).
 945 // Not inline to avoid circular ref.
 946 bool Method::check_code() const {
 947   // cached in a register or local.  There's a race on the value of the field.
 948   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 949   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 950 }
 951 
 952 // Install compiled code.  Instantly it can execute.
 953 void Method::set_code(methodHandle mh, nmethod *code) {
 954   assert( code, "use clear_code to remove code" );
 955   assert( mh->check_code(), "" );
 956 
 957   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 958 
 959   // These writes must happen in this order, because the interpreter will
 960   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 961   // which jumps to _from_compiled_entry.
 962   mh->_code = code;             // Assign before allowing compiled code to exec
 963 
 964   int comp_level = code->comp_level();
 965   // In theory there could be a race here. In practice it is unlikely
 966   // and not worth worrying about.
 967   if (comp_level > mh->highest_comp_level()) {
 968     mh->set_highest_comp_level(comp_level);
 969   }
 970 
 971   OrderAccess::storestore();
 972 #ifdef SHARK
 973   mh->_from_interpreted_entry = code->insts_begin();
 974 #else //!SHARK
 975   mh->_from_compiled_entry = code->verified_entry_point();
 976   OrderAccess::storestore();
 977   // Instantly compiled code can execute.
 978   if (!mh->is_method_handle_intrinsic())
 979     mh->_from_interpreted_entry = mh->get_i2c_entry();
 980 #endif //!SHARK
 981 }
 982 
 983 
 984 bool Method::is_overridden_in(Klass* k) const {
 985   InstanceKlass* ik = InstanceKlass::cast(k);
 986 
 987   if (ik->is_interface()) return false;
 988 
 989   // If method is an interface, we skip it - except if it
 990   // is a miranda method
 991   if (method_holder()->is_interface()) {
 992     // Check that method is not a miranda method
 993     if (ik->lookup_method(name(), signature()) == NULL) {
 994       // No implementation exist - so miranda method
 995       return false;
 996     }
 997     return true;
 998   }
 999 
1000   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1001   assert(ik->vtable() != NULL, "vtable should exist");
1002   if (!has_vtable_index()) {
1003     return false;
1004   } else {
1005     Method* vt_m = ik->method_at_vtable(vtable_index());
1006     return vt_m != this;
1007   }
1008 }
1009 
1010 
1011 // give advice about whether this Method* should be cached or not
1012 bool Method::should_not_be_cached() const {
1013   if (is_old()) {
1014     // This method has been redefined. It is either EMCP or obsolete
1015     // and we don't want to cache it because that would pin the method
1016     // down and prevent it from being collectible if and when it
1017     // finishes executing.
1018     return true;
1019   }
1020 
1021   // caching this method should be just fine
1022   return false;
1023 }
1024 
1025 
1026 /**
1027  *  Returns true if this is one of the specially treated methods for
1028  *  security related stack walks (like Reflection.getCallerClass).
1029  */
1030 bool Method::is_ignored_by_security_stack_walk() const {
1031   if (intrinsic_id() == vmIntrinsics::_invoke) {
1032     // This is Method.invoke() -- ignore it
1033     return true;
1034   }
1035   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1036     // This is an auxilary frame -- ignore it
1037     return true;
1038   }
1039   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1040     // This is an internal adapter frame for method handles -- ignore it
1041     return true;
1042   }
1043   return false;
1044 }
1045 
1046 
1047 // Constant pool structure for invoke methods:
1048 enum {
1049   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1050   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1051   _imcp_limit
1052 };
1053 
1054 // Test if this method is an MH adapter frame generated by Java code.
1055 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1056 bool Method::is_compiled_lambda_form() const {
1057   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1058 }
1059 
1060 // Test if this method is an internal MH primitive method.
1061 bool Method::is_method_handle_intrinsic() const {
1062   vmIntrinsics::ID iid = intrinsic_id();
1063   return (MethodHandles::is_signature_polymorphic(iid) &&
1064           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1065 }
1066 
1067 bool Method::has_member_arg() const {
1068   vmIntrinsics::ID iid = intrinsic_id();
1069   return (MethodHandles::is_signature_polymorphic(iid) &&
1070           MethodHandles::has_member_arg(iid));
1071 }
1072 
1073 // Make an instance of a signature-polymorphic internal MH primitive.
1074 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1075                                                          Symbol* signature,
1076                                                          TRAPS) {
1077   ResourceMark rm;
1078   methodHandle empty;
1079 
1080   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1081   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1082   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1083   if (TraceMethodHandles) {
1084     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1085   }
1086 
1087   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1088   name->increment_refcount();
1089   signature->increment_refcount();
1090 
1091   int cp_length = _imcp_limit;
1092   ClassLoaderData* loader_data = holder->class_loader_data();
1093   constantPoolHandle cp;
1094   {
1095     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1096     cp = constantPoolHandle(THREAD, cp_oop);
1097   }
1098   cp->set_pool_holder(InstanceKlass::cast(holder()));
1099   cp->symbol_at_put(_imcp_invoke_name,       name);
1100   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1101   cp->set_has_preresolution();
1102 
1103   // decide on access bits:  public or not?
1104   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1105   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1106   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1107   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1108 
1109   methodHandle m;
1110   {
1111     InlineTableSizes sizes;
1112     Method* m_oop = Method::allocate(loader_data, 0,
1113                                      accessFlags_from(flags_bits), &sizes,
1114                                      ConstMethod::NORMAL, CHECK_(empty));
1115     m = methodHandle(THREAD, m_oop);
1116   }
1117   m->set_constants(cp());
1118   m->set_name_index(_imcp_invoke_name);
1119   m->set_signature_index(_imcp_invoke_signature);
1120   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1121   assert(m->signature() == signature, "");
1122 #ifdef CC_INTERP
1123   ResultTypeFinder rtf(signature);
1124   m->set_result_index(rtf.type());
1125 #endif
1126   m->compute_size_of_parameters(THREAD);
1127   m->init_intrinsic_id();
1128   assert(m->is_method_handle_intrinsic(), "");
1129 #ifdef ASSERT
1130   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1131   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1132   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1133 #endif //ASSERT
1134 
1135   // Finally, set up its entry points.
1136   assert(m->can_be_statically_bound(), "");
1137   m->set_vtable_index(Method::nonvirtual_vtable_index);
1138   m->link_method(m, CHECK_(empty));
1139 
1140   if (TraceMethodHandles && (Verbose || WizardMode))
1141     m->print_on(tty);
1142 
1143   return m;
1144 }
1145 
1146 Klass* Method::check_non_bcp_klass(Klass* klass) {
1147   if (klass != NULL && klass->class_loader() != NULL) {
1148     if (klass->oop_is_objArray())
1149       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1150     return klass;
1151   }
1152   return NULL;
1153 }
1154 
1155 
1156 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1157                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1158   // Code below does not work for native methods - they should never get rewritten anyway
1159   assert(!m->is_native(), "cannot rewrite native methods");
1160   // Allocate new Method*
1161   AccessFlags flags = m->access_flags();
1162 
1163   ConstMethod* cm = m->constMethod();
1164   int checked_exceptions_len = cm->checked_exceptions_length();
1165   int localvariable_len = cm->localvariable_table_length();
1166   int exception_table_len = cm->exception_table_length();
1167   int method_parameters_len = cm->method_parameters_length();
1168   int method_annotations_len = cm->method_annotations_length();
1169   int parameter_annotations_len = cm->parameter_annotations_length();
1170   int type_annotations_len = cm->type_annotations_length();
1171   int default_annotations_len = cm->default_annotations_length();
1172 
1173   InlineTableSizes sizes(
1174       localvariable_len,
1175       new_compressed_linenumber_size,
1176       exception_table_len,
1177       checked_exceptions_len,
1178       method_parameters_len,
1179       cm->generic_signature_index(),
1180       method_annotations_len,
1181       parameter_annotations_len,
1182       type_annotations_len,
1183       default_annotations_len,
1184       0);
1185 
1186   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1187   Method* newm_oop = Method::allocate(loader_data,
1188                                       new_code_length,
1189                                       flags,
1190                                       &sizes,
1191                                       m->method_type(),
1192                                       CHECK_(methodHandle()));
1193   methodHandle newm (THREAD, newm_oop);
1194   int new_method_size = newm->method_size();
1195 
1196   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1197   ConstMethod* newcm = newm->constMethod();
1198   int new_const_method_size = newm->constMethod()->size();
1199 
1200   memcpy(newm(), m(), sizeof(Method));
1201 
1202   // Create shallow copy of ConstMethod.
1203   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1204 
1205   // Reset correct method/const method, method size, and parameter info
1206   newm->set_constMethod(newcm);
1207   newm->constMethod()->set_code_size(new_code_length);
1208   newm->constMethod()->set_constMethod_size(new_const_method_size);
1209   newm->set_method_size(new_method_size);
1210   assert(newm->code_size() == new_code_length, "check");
1211   assert(newm->method_parameters_length() == method_parameters_len, "check");
1212   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1213   assert(newm->exception_table_length() == exception_table_len, "check");
1214   assert(newm->localvariable_table_length() == localvariable_len, "check");
1215   // Copy new byte codes
1216   memcpy(newm->code_base(), new_code, new_code_length);
1217   // Copy line number table
1218   if (new_compressed_linenumber_size > 0) {
1219     memcpy(newm->compressed_linenumber_table(),
1220            new_compressed_linenumber_table,
1221            new_compressed_linenumber_size);
1222   }
1223   // Copy method_parameters
1224   if (method_parameters_len > 0) {
1225     memcpy(newm->method_parameters_start(),
1226            m->method_parameters_start(),
1227            method_parameters_len * sizeof(MethodParametersElement));
1228   }
1229   // Copy checked_exceptions
1230   if (checked_exceptions_len > 0) {
1231     memcpy(newm->checked_exceptions_start(),
1232            m->checked_exceptions_start(),
1233            checked_exceptions_len * sizeof(CheckedExceptionElement));
1234   }
1235   // Copy exception table
1236   if (exception_table_len > 0) {
1237     memcpy(newm->exception_table_start(),
1238            m->exception_table_start(),
1239            exception_table_len * sizeof(ExceptionTableElement));
1240   }
1241   // Copy local variable number table
1242   if (localvariable_len > 0) {
1243     memcpy(newm->localvariable_table_start(),
1244            m->localvariable_table_start(),
1245            localvariable_len * sizeof(LocalVariableTableElement));
1246   }
1247   // Copy stackmap table
1248   if (m->has_stackmap_table()) {
1249     int code_attribute_length = m->stackmap_data()->length();
1250     Array<u1>* stackmap_data =
1251       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1252     memcpy((void*)stackmap_data->adr_at(0),
1253            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1254     newm->set_stackmap_data(stackmap_data);
1255   }
1256 
1257   // copy annotations over to new method
1258   newcm->copy_annotations_from(cm);
1259   return newm;
1260 }
1261 
1262 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1263   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1264   // because we are not loading from core libraries
1265   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1266   // which does not use the class default class loader so we check for its loader here
1267   InstanceKlass* ik = InstanceKlass::cast(holder);
1268   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1269     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1270   }
1271 
1272   // see if the klass name is well-known:
1273   Symbol* klass_name = ik->name();
1274   return vmSymbols::find_sid(klass_name);
1275 }
1276 
1277 void Method::init_intrinsic_id() {
1278   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1279   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1280   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1281   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1282 
1283   // the klass name is well-known:
1284   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1285   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1286 
1287   // ditto for method and signature:
1288   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1289   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1290       && name_id == vmSymbols::NO_SID)
1291     return;
1292   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1293   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1294       && sig_id == vmSymbols::NO_SID)  return;
1295   jshort flags = access_flags().as_short();
1296 
1297   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1298   if (id != vmIntrinsics::_none) {
1299     set_intrinsic_id(id);
1300     return;
1301   }
1302 
1303   // A few slightly irregular cases:
1304   switch (klass_id) {
1305   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1306     // Second chance: check in regular Math.
1307     switch (name_id) {
1308     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1309     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1310     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1311       // pretend it is the corresponding method in the non-strict class:
1312       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1313       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1314       break;
1315     }
1316     break;
1317 
1318   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1319   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1320     if (!is_native())  break;
1321     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1322     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1323       id = vmIntrinsics::_none;
1324     break;
1325   }
1326 
1327   if (id != vmIntrinsics::_none) {
1328     // Set up its iid.  It is an alias method.
1329     set_intrinsic_id(id);
1330     return;
1331   }
1332 }
1333 
1334 // These two methods are static since a GC may move the Method
1335 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1336   if (THREAD->is_Compiler_thread()) {
1337     // There is nothing useful this routine can do from within the Compile thread.
1338     // Hopefully, the signature contains only well-known classes.
1339     // We could scan for this and return true/false, but the caller won't care.
1340     return false;
1341   }
1342   bool sig_is_loaded = true;
1343   Handle class_loader(THREAD, m->method_holder()->class_loader());
1344   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1345   ResourceMark rm(THREAD);
1346   Symbol*  signature = m->signature();
1347   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1348     if (ss.is_object()) {
1349       Symbol* sym = ss.as_symbol(CHECK_(false));
1350       Symbol*  name  = sym;
1351       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1352                                              protection_domain, THREAD);
1353       // We are loading classes eagerly. If a ClassNotFoundException or
1354       // a LinkageError was generated, be sure to ignore it.
1355       if (HAS_PENDING_EXCEPTION) {
1356         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1357             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1358           CLEAR_PENDING_EXCEPTION;
1359         } else {
1360           return false;
1361         }
1362       }
1363       if( klass == NULL) { sig_is_loaded = false; }
1364     }
1365   }
1366   return sig_is_loaded;
1367 }
1368 
1369 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1370   Handle class_loader(THREAD, m->method_holder()->class_loader());
1371   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1372   ResourceMark rm(THREAD);
1373   Symbol*  signature = m->signature();
1374   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1375     if (ss.type() == T_OBJECT) {
1376       Symbol* name = ss.as_symbol_or_null();
1377       if (name == NULL) return true;
1378       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1379       if (klass == NULL) return true;
1380     }
1381   }
1382   return false;
1383 }
1384 
1385 // Exposed so field engineers can debug VM
1386 void Method::print_short_name(outputStream* st) {
1387   ResourceMark rm;
1388 #ifdef PRODUCT
1389   st->print(" %s::", method_holder()->external_name());
1390 #else
1391   st->print(" %s::", method_holder()->internal_name());
1392 #endif
1393   name()->print_symbol_on(st);
1394   if (WizardMode) signature()->print_symbol_on(st);
1395   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1396     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1397 }
1398 
1399 // Comparer for sorting an object array containing
1400 // Method*s.
1401 static int method_comparator(Method* a, Method* b) {
1402   return a->name()->fast_compare(b->name());
1403 }
1404 
1405 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1406 // default_methods also uses this without the ordering for fast find_method
1407 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1408   int length = methods->length();
1409   if (length > 1) {
1410     {
1411       No_Safepoint_Verifier nsv;
1412       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1413     }
1414     // Reset method ordering
1415     if (set_idnums) {
1416       for (int i = 0; i < length; i++) {
1417         Method* m = methods->at(i);
1418         m->set_method_idnum(i);
1419       }
1420     }
1421   }
1422 }
1423 
1424 //-----------------------------------------------------------------------------------
1425 // Non-product code unless JVM/TI needs it
1426 
1427 #if !defined(PRODUCT) || INCLUDE_JVMTI
1428 class SignatureTypePrinter : public SignatureTypeNames {
1429  private:
1430   outputStream* _st;
1431   bool _use_separator;
1432 
1433   void type_name(const char* name) {
1434     if (_use_separator) _st->print(", ");
1435     _st->print("%s", name);
1436     _use_separator = true;
1437   }
1438 
1439  public:
1440   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1441     _st = st;
1442     _use_separator = false;
1443   }
1444 
1445   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1446   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1447 };
1448 
1449 
1450 void Method::print_name(outputStream* st) {
1451   Thread *thread = Thread::current();
1452   ResourceMark rm(thread);
1453   SignatureTypePrinter sig(signature(), st);
1454   st->print("%s ", is_static() ? "static" : "virtual");
1455   sig.print_returntype();
1456   st->print(" %s.", method_holder()->internal_name());
1457   name()->print_symbol_on(st);
1458   st->print("(");
1459   sig.print_parameters();
1460   st->print(")");
1461 }
1462 #endif // !PRODUCT || INCLUDE_JVMTI
1463 
1464 
1465 void Method::print_codes_on(outputStream* st) const {
1466   print_codes_on(0, code_size(), st);
1467 }
1468 
1469 void Method::print_codes_on(int from, int to, outputStream* st) const {
1470   Thread *thread = Thread::current();
1471   ResourceMark rm(thread);
1472   methodHandle mh (thread, (Method*)this);
1473   BytecodeStream s(mh);
1474   s.set_interval(from, to);
1475   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1476   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1477 }
1478 
1479 
1480 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1481 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1482 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1483 // as end-of-stream terminator.
1484 
1485 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1486   // bci and line number does not compress into single byte.
1487   // Write out escape character and use regular compression for bci and line number.
1488   write_byte((jubyte)0xFF);
1489   write_signed_int(bci_delta);
1490   write_signed_int(line_delta);
1491 }
1492 
1493 // See comment in method.hpp which explains why this exists.
1494 #if defined(_M_AMD64) && _MSC_VER >= 1400
1495 #pragma optimize("", off)
1496 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1497   write_pair_inline(bci, line);
1498 }
1499 #pragma optimize("", on)
1500 #endif
1501 
1502 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1503   _bci = 0;
1504   _line = 0;
1505 };
1506 
1507 
1508 bool CompressedLineNumberReadStream::read_pair() {
1509   jubyte next = read_byte();
1510   // Check for terminator
1511   if (next == 0) return false;
1512   if (next == 0xFF) {
1513     // Escape character, regular compression used
1514     _bci  += read_signed_int();
1515     _line += read_signed_int();
1516   } else {
1517     // Single byte compression used
1518     _bci  += next >> 3;
1519     _line += next & 0x7;
1520   }
1521   return true;
1522 }
1523 
1524 
1525 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1526   BreakpointInfo* bp = method_holder()->breakpoints();
1527   for (; bp != NULL; bp = bp->next()) {
1528     if (bp->match(this, bci)) {
1529       return bp->orig_bytecode();
1530     }
1531   }
1532   {
1533     ResourceMark rm;
1534     fatal(err_msg("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci));
1535   }
1536   return Bytecodes::_shouldnotreachhere;
1537 }
1538 
1539 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1540   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1541   BreakpointInfo* bp = method_holder()->breakpoints();
1542   for (; bp != NULL; bp = bp->next()) {
1543     if (bp->match(this, bci)) {
1544       bp->set_orig_bytecode(code);
1545       // and continue, in case there is more than one
1546     }
1547   }
1548 }
1549 
1550 void Method::set_breakpoint(int bci) {
1551   InstanceKlass* ik = method_holder();
1552   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1553   bp->set_next(ik->breakpoints());
1554   ik->set_breakpoints(bp);
1555   // do this last:
1556   bp->set(this);
1557 }
1558 
1559 static void clear_matches(Method* m, int bci) {
1560   InstanceKlass* ik = m->method_holder();
1561   BreakpointInfo* prev_bp = NULL;
1562   BreakpointInfo* next_bp;
1563   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1564     next_bp = bp->next();
1565     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1566     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1567       // do this first:
1568       bp->clear(m);
1569       // unhook it
1570       if (prev_bp != NULL)
1571         prev_bp->set_next(next_bp);
1572       else
1573         ik->set_breakpoints(next_bp);
1574       delete bp;
1575       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1576       // at same location. So we have multiple matching (method_index and bci)
1577       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1578       // breakpoint for clear_breakpoint request and keep all other method versions
1579       // BreakpointInfo for future clear_breakpoint request.
1580       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1581       // which is being called when class is unloaded. We delete all the Breakpoint
1582       // information for all versions of method. We may not correctly restore the original
1583       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1584       // so these methods won't be used anymore.
1585       if (bci >= 0) {
1586         break;
1587       }
1588     } else {
1589       // This one is a keeper.
1590       prev_bp = bp;
1591     }
1592   }
1593 }
1594 
1595 void Method::clear_breakpoint(int bci) {
1596   assert(bci >= 0, "");
1597   clear_matches(this, bci);
1598 }
1599 
1600 void Method::clear_all_breakpoints() {
1601   clear_matches(this, -1);
1602 }
1603 
1604 
1605 int Method::invocation_count() {
1606   MethodCounters *mcs = method_counters();
1607   if (TieredCompilation) {
1608     MethodData* const mdo = method_data();
1609     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1610         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1611       return InvocationCounter::count_limit;
1612     } else {
1613       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1614              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1615     }
1616   } else {
1617     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1618   }
1619 }
1620 
1621 int Method::backedge_count() {
1622   MethodCounters *mcs = method_counters();
1623   if (TieredCompilation) {
1624     MethodData* const mdo = method_data();
1625     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1626         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1627       return InvocationCounter::count_limit;
1628     } else {
1629       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1630              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1631     }
1632   } else {
1633     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1634   }
1635 }
1636 
1637 int Method::highest_comp_level() const {
1638   const MethodData* mdo = method_data();
1639   if (mdo != NULL) {
1640     return mdo->highest_comp_level();
1641   } else {
1642     return CompLevel_none;
1643   }
1644 }
1645 
1646 int Method::highest_osr_comp_level() const {
1647   const MethodData* mdo = method_data();
1648   if (mdo != NULL) {
1649     return mdo->highest_osr_comp_level();
1650   } else {
1651     return CompLevel_none;
1652   }
1653 }
1654 
1655 void Method::set_highest_comp_level(int level) {
1656   MethodData* mdo = method_data();
1657   if (mdo != NULL) {
1658     mdo->set_highest_comp_level(level);
1659   }
1660 }
1661 
1662 void Method::set_highest_osr_comp_level(int level) {
1663   MethodData* mdo = method_data();
1664   if (mdo != NULL) {
1665     mdo->set_highest_osr_comp_level(level);
1666   }
1667 }
1668 
1669 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1670   _bci = bci;
1671   _name_index = m->name_index();
1672   _signature_index = m->signature_index();
1673   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1674   if (_orig_bytecode == Bytecodes::_breakpoint)
1675     _orig_bytecode = m->orig_bytecode_at(_bci);
1676   _next = NULL;
1677 }
1678 
1679 void BreakpointInfo::set(Method* method) {
1680 #ifdef ASSERT
1681   {
1682     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1683     if (code == Bytecodes::_breakpoint)
1684       code = method->orig_bytecode_at(_bci);
1685     assert(orig_bytecode() == code, "original bytecode must be the same");
1686   }
1687 #endif
1688   Thread *thread = Thread::current();
1689   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1690   method->incr_number_of_breakpoints(thread);
1691   SystemDictionary::notice_modification();
1692   {
1693     // Deoptimize all dependents on this method
1694     HandleMark hm(thread);
1695     methodHandle mh(thread, method);
1696     Universe::flush_dependents_on_method(mh);
1697   }
1698 }
1699 
1700 void BreakpointInfo::clear(Method* method) {
1701   *method->bcp_from(_bci) = orig_bytecode();
1702   assert(method->number_of_breakpoints() > 0, "must not go negative");
1703   method->decr_number_of_breakpoints(Thread::current());
1704 }
1705 
1706 // jmethodID handling
1707 
1708 // This is a block allocating object, sort of like JNIHandleBlock, only a
1709 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1710 // deleted and so we can do some suboptimal things.
1711 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1712 // never get rid of it.
1713 // It would be nice to be able to parameterize the number of methods for
1714 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1715 // into templates.
1716 
1717 // I feel like this brain dead class should exist somewhere in the STL
1718 
1719 class JNIMethodBlock : public CHeapObj<mtClass> {
1720   enum { number_of_methods = 8 };
1721 
1722   Method*         _methods[number_of_methods];
1723   int             _top;
1724   JNIMethodBlock* _next;
1725  public:
1726   static Method* const _free_method;
1727 
1728   JNIMethodBlock() : _next(NULL), _top(0) {
1729     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1730   }
1731 
1732   Method** add_method(Method* m) {
1733     if (_top < number_of_methods) {
1734       // top points to the next free entry.
1735       int i = _top;
1736       _methods[i] = m;
1737       _top++;
1738       return &_methods[i];
1739     } else if (_top == number_of_methods) {
1740       // if the next free entry ran off the block see if there's a free entry
1741       for (int i = 0; i< number_of_methods; i++) {
1742         if (_methods[i] == _free_method) {
1743           _methods[i] = m;
1744           return &_methods[i];
1745         }
1746       }
1747       // Only check each block once for frees.  They're very unlikely.
1748       // Increment top past the end of the block.
1749       _top++;
1750     }
1751     // need to allocate a next block.
1752     if (_next == NULL) {
1753       _next = new JNIMethodBlock();
1754     }
1755     return _next->add_method(m);
1756   }
1757 
1758   bool contains(Method** m) {
1759     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1760       for (int i = 0; i< number_of_methods; i++) {
1761         if (&(b->_methods[i]) == m) {
1762           return true;
1763         }
1764       }
1765     }
1766     return false;  // not found
1767   }
1768 
1769   // Doesn't really destroy it, just marks it as free so it can be reused.
1770   void destroy_method(Method** m) {
1771 #ifdef ASSERT
1772     assert(contains(m), "should be a methodID");
1773 #endif // ASSERT
1774     *m = _free_method;
1775   }
1776 
1777   // During class unloading the methods are cleared, which is different
1778   // than freed.
1779   void clear_all_methods() {
1780     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1781       for (int i = 0; i< number_of_methods; i++) {
1782         _methods[i] = NULL;
1783       }
1784     }
1785   }
1786 #ifndef PRODUCT
1787   int count_methods() {
1788     // count all allocated methods
1789     int count = 0;
1790     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1791       for (int i = 0; i< number_of_methods; i++) {
1792         if (_methods[i] != _free_method) count++;
1793       }
1794     }
1795     return count;
1796   }
1797 #endif // PRODUCT
1798 };
1799 
1800 // Something that can't be mistaken for an address or a markOop
1801 Method* const JNIMethodBlock::_free_method = (Method*)55;
1802 
1803 // Add a method id to the jmethod_ids
1804 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1805   ClassLoaderData* cld = loader_data;
1806 
1807   if (!SafepointSynchronize::is_at_safepoint()) {
1808     // Have to add jmethod_ids() to class loader data thread-safely.
1809     // Also have to add the method to the list safely, which the cld lock
1810     // protects as well.
1811     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1812     if (cld->jmethod_ids() == NULL) {
1813       cld->set_jmethod_ids(new JNIMethodBlock());
1814     }
1815     // jmethodID is a pointer to Method*
1816     return (jmethodID)cld->jmethod_ids()->add_method(m);
1817   } else {
1818     // At safepoint, we are single threaded and can set this.
1819     if (cld->jmethod_ids() == NULL) {
1820       cld->set_jmethod_ids(new JNIMethodBlock());
1821     }
1822     // jmethodID is a pointer to Method*
1823     return (jmethodID)cld->jmethod_ids()->add_method(m);
1824   }
1825 }
1826 
1827 // Mark a jmethodID as free.  This is called when there is a data race in
1828 // InstanceKlass while creating the jmethodID cache.
1829 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1830   ClassLoaderData* cld = loader_data;
1831   Method** ptr = (Method**)m;
1832   assert(cld->jmethod_ids() != NULL, "should have method handles");
1833   cld->jmethod_ids()->destroy_method(ptr);
1834 }
1835 
1836 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1837   // Can't assert the method_holder is the same because the new method has the
1838   // scratch method holder.
1839   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1840            == new_method->method_holder()->class_loader(),
1841          "changing to a different class loader");
1842   // Just change the method in place, jmethodID pointer doesn't change.
1843   *((Method**)jmid) = new_method;
1844 }
1845 
1846 bool Method::is_method_id(jmethodID mid) {
1847   Method* m = resolve_jmethod_id(mid);
1848   assert(m != NULL, "should be called with non-null method");
1849   InstanceKlass* ik = m->method_holder();
1850   ClassLoaderData* cld = ik->class_loader_data();
1851   if (cld->jmethod_ids() == NULL) return false;
1852   return (cld->jmethod_ids()->contains((Method**)mid));
1853 }
1854 
1855 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1856   if (mid == NULL) return NULL;
1857   Method* o = resolve_jmethod_id(mid);
1858   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1859     return NULL;
1860   }
1861   return o;
1862 };
1863 
1864 void Method::set_on_stack(const bool value) {
1865   // Set both the method itself and its constant pool.  The constant pool
1866   // on stack means some method referring to it is also on the stack.
1867   _access_flags.set_on_stack(value);
1868   constants()->set_on_stack(value);
1869   if (value) MetadataOnStackMark::record(this);
1870 }
1871 
1872 // Called when the class loader is unloaded to make all methods weak.
1873 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1874   loader_data->jmethod_ids()->clear_all_methods();
1875 }
1876 
1877 bool Method::has_method_vptr(const void* ptr) {
1878   Method m;
1879   // This assumes that the vtbl pointer is the first word of a C++ object.
1880   // This assumption is also in universe.cpp patch_klass_vtble
1881   void* vtbl2 = dereference_vptr((const void*)&m);
1882   void* this_vtbl = dereference_vptr(ptr);
1883   return vtbl2 == this_vtbl;
1884 }
1885 
1886 // Check that this pointer is valid by checking that the vtbl pointer matches
1887 bool Method::is_valid_method() const {
1888   if (this == NULL) {
1889     return false;
1890   } else if (!is_metaspace_object()) {
1891     return false;
1892   } else {
1893     return has_method_vptr((const void*)this);
1894   }
1895 }
1896 
1897 #ifndef PRODUCT
1898 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1899   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1900 }
1901 #endif // PRODUCT
1902 
1903 
1904 // Printing
1905 
1906 #ifndef PRODUCT
1907 
1908 void Method::print_on(outputStream* st) const {
1909   ResourceMark rm;
1910   assert(is_method(), "must be method");
1911   st->print_cr("%s", internal_name());
1912   // get the effect of PrintOopAddress, always, for methods:
1913   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1914   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1915   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1916   constants()->print_value_on(st); st->cr();
1917   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1918   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1919   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1920   st->print_cr(" - max stack:         %d",   max_stack());
1921   st->print_cr(" - max locals:        %d",   max_locals());
1922   st->print_cr(" - size of params:    %d",   size_of_parameters());
1923   st->print_cr(" - method size:       %d",   method_size());
1924   if (intrinsic_id() != vmIntrinsics::_none)
1925     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1926   if (highest_comp_level() != CompLevel_none)
1927     st->print_cr(" - highest level:     %d", highest_comp_level());
1928   st->print_cr(" - vtable index:      %d",   _vtable_index);
1929   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1930   st->print(   " - adapters:          ");
1931   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1932   if (a == NULL)
1933     st->print_cr(INTPTR_FORMAT, a);
1934   else
1935     a->print_adapter_on(st);
1936   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1937   st->print_cr(" - code size:         %d",   code_size());
1938   if (code_size() != 0) {
1939     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1940     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1941   }
1942   if (method_data() != NULL) {
1943     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1944   }
1945   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1946   if (checked_exceptions_length() > 0) {
1947     CheckedExceptionElement* table = checked_exceptions_start();
1948     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1949     if (Verbose) {
1950       for (int i = 0; i < checked_exceptions_length(); i++) {
1951         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1952       }
1953     }
1954   }
1955   if (has_linenumber_table()) {
1956     u_char* table = compressed_linenumber_table();
1957     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1958     if (Verbose) {
1959       CompressedLineNumberReadStream stream(table);
1960       while (stream.read_pair()) {
1961         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1962       }
1963     }
1964   }
1965   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1966   if (localvariable_table_length() > 0) {
1967     LocalVariableTableElement* table = localvariable_table_start();
1968     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1969     if (Verbose) {
1970       for (int i = 0; i < localvariable_table_length(); i++) {
1971         int bci = table[i].start_bci;
1972         int len = table[i].length;
1973         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1974         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
1975         int slot = table[i].slot;
1976         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
1977       }
1978     }
1979   }
1980   if (code() != NULL) {
1981     st->print   (" - compiled code: ");
1982     code()->print_value_on(st);
1983   }
1984   if (is_native()) {
1985     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
1986     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
1987   }
1988 }
1989 
1990 #endif //PRODUCT
1991 
1992 void Method::print_value_on(outputStream* st) const {
1993   assert(is_method(), "must be method");
1994   st->print("%s", internal_name());
1995   print_address_on(st);
1996   st->print(" ");
1997   name()->print_value_on(st);
1998   st->print(" ");
1999   signature()->print_value_on(st);
2000   st->print(" in ");
2001   method_holder()->print_value_on(st);
2002   if (WizardMode) st->print("#%d", _vtable_index);
2003   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2004   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2005 }
2006 
2007 #if INCLUDE_SERVICES
2008 // Size Statistics
2009 void Method::collect_statistics(KlassSizeStats *sz) const {
2010   int mysize = sz->count(this);
2011   sz->_method_bytes += mysize;
2012   sz->_method_all_bytes += mysize;
2013   sz->_rw_bytes += mysize;
2014 
2015   if (constMethod()) {
2016     constMethod()->collect_statistics(sz);
2017   }
2018   if (method_data()) {
2019     method_data()->collect_statistics(sz);
2020   }
2021 }
2022 #endif // INCLUDE_SERVICES
2023 
2024 // Verification
2025 
2026 void Method::verify_on(outputStream* st) {
2027   guarantee(is_method(), "object must be method");
2028   guarantee(constants()->is_constantPool(), "should be constant pool");
2029   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2030   MethodData* md = method_data();
2031   guarantee(md == NULL ||
2032       md->is_methodData(), "should be method data");
2033 }