1 /*
   2  * Copyright (c) 1997, 2013, 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/relocator.hpp"
  53 #include "runtime/sharedRuntime.hpp"
  54 #include "runtime/signature.hpp"
  55 #include "utilities/quickSort.hpp"
  56 #include "utilities/xmlstream.hpp"
  57 
  58 
  59 // Implementation of Method
  60 
  61 Method* Method::allocate(ClassLoaderData* loader_data,
  62                          int byte_code_size,
  63                          AccessFlags access_flags,
  64                          int compressed_line_number_size,
  65                          int localvariable_table_length,
  66                          int exception_table_length,
  67                          int checked_exceptions_length,
  68                          int method_parameters_length,
  69                          u2  generic_signature_index,
  70                          ConstMethod::MethodType method_type,
  71                          TRAPS) {
  72   assert(!access_flags.is_native() || byte_code_size == 0,
  73          "native methods should not contain byte codes");
  74   ConstMethod* cm = ConstMethod::allocate(loader_data,
  75                                           byte_code_size,
  76                                           compressed_line_number_size,
  77                                           localvariable_table_length,
  78                                           exception_table_length,
  79                                           checked_exceptions_length,
  80                                           method_parameters_length,
  81                                           generic_signature_index,
  82                                           method_type,
  83                                           CHECK_NULL);
  84 
  85   int size = Method::size(access_flags.is_native());
  86 
  87   return new (loader_data, size, false, THREAD) Method(cm, access_flags, size);
  88 }
  89 
  90 Method::Method(ConstMethod* xconst,
  91                              AccessFlags access_flags, int size) {
  92   No_Safepoint_Verifier no_safepoint;
  93   set_constMethod(xconst);
  94   set_access_flags(access_flags);
  95   set_method_size(size);
  96   set_name_index(0);
  97   set_signature_index(0);
  98 #ifdef CC_INTERP
  99   set_result_index(T_VOID);
 100 #endif
 101   set_constants(NULL);
 102   set_max_stack(0);
 103   set_max_locals(0);
 104   set_intrinsic_id(vmIntrinsics::_none);
 105   set_jfr_towrite(false);
 106   set_method_data(NULL);
 107   set_interpreter_throwout_count(0);
 108   set_vtable_index(Method::garbage_vtable_index);
 109 
 110   // Fix and bury in Method*
 111   set_interpreter_entry(NULL); // sets i2i entry and from_int
 112   set_adapter_entry(NULL);
 113   clear_code(); // from_c/from_i get set to c2i/i2i
 114 
 115   if (access_flags.is_native()) {
 116     clear_native_function();
 117     set_signature_handler(NULL);
 118   }
 119 
 120   NOT_PRODUCT(set_compiled_invocation_count(0);)
 121   set_interpreter_invocation_count(0);
 122   invocation_counter()->init();
 123   backedge_counter()->init();
 124   clear_number_of_breakpoints();
 125 
 126 #ifdef TIERED
 127   set_rate(0);
 128   set_prev_event_count(0);
 129   set_prev_time(0);
 130 #endif
 131 }
 132 
 133 // Release Method*.  The nmethod will be gone when we get here because
 134 // we've walked the code cache.
 135 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 136   MetadataFactory::free_metadata(loader_data, constMethod());
 137   set_constMethod(NULL);
 138   MetadataFactory::free_metadata(loader_data, method_data());
 139   set_method_data(NULL);
 140   // The nmethod will be gone when we get here.
 141   if (code() != NULL) _code = NULL;
 142 }
 143 
 144 address Method::get_i2c_entry() {
 145   assert(_adapter != NULL, "must have");
 146   return _adapter->get_i2c_entry();
 147 }
 148 
 149 address Method::get_c2i_entry() {
 150   assert(_adapter != NULL, "must have");
 151   return _adapter->get_c2i_entry();
 152 }
 153 
 154 address Method::get_c2i_unverified_entry() {
 155   assert(_adapter != NULL, "must have");
 156   return _adapter->get_c2i_unverified_entry();
 157 }
 158 
 159 char* Method::name_and_sig_as_C_string() const {
 160   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 161 }
 162 
 163 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 164   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 165 }
 166 
 167 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 168   const char* klass_name = klass->external_name();
 169   int klass_name_len  = (int)strlen(klass_name);
 170   int method_name_len = method_name->utf8_length();
 171   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 172   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 173   strcpy(dest, klass_name);
 174   dest[klass_name_len] = '.';
 175   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 176   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 177   dest[len] = 0;
 178   return dest;
 179 }
 180 
 181 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 182   Symbol* klass_name = klass->name();
 183   klass_name->as_klass_external_name(buf, size);
 184   int len = (int)strlen(buf);
 185 
 186   if (len < size - 1) {
 187     buf[len++] = '.';
 188 
 189     method_name->as_C_string(&(buf[len]), size - len);
 190     len = (int)strlen(buf);
 191 
 192     signature->as_C_string(&(buf[len]), size - len);
 193   }
 194 
 195   return buf;
 196 }
 197 
 198 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 199   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 200   // access exception table
 201   ExceptionTable table(mh());
 202   int length = table.length();
 203   // iterate through all entries sequentially
 204   constantPoolHandle pool(THREAD, mh->constants());
 205   for (int i = 0; i < length; i ++) {
 206     //reacquire the table in case a GC happened
 207     ExceptionTable table(mh());
 208     int beg_bci = table.start_pc(i);
 209     int end_bci = table.end_pc(i);
 210     assert(beg_bci <= end_bci, "inconsistent exception table");
 211     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 212       // exception handler bci range covers throw_bci => investigate further
 213       int handler_bci = table.handler_pc(i);
 214       int klass_index = table.catch_type_index(i);
 215       if (klass_index == 0) {
 216         return handler_bci;
 217       } else if (ex_klass.is_null()) {
 218         return handler_bci;
 219       } else {
 220         // we know the exception class => get the constraint class
 221         // this may require loading of the constraint class; if verification
 222         // fails or some other exception occurs, return handler_bci
 223         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 224         KlassHandle klass = KlassHandle(THREAD, k);
 225         assert(klass.not_null(), "klass not loaded");
 226         if (ex_klass->is_subtype_of(klass())) {
 227           return handler_bci;
 228         }
 229       }
 230     }
 231   }
 232 
 233   return -1;
 234 }
 235 
 236 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 237 
 238   Thread* myThread    = Thread::current();
 239   methodHandle h_this(myThread, this);
 240 #ifdef ASSERT
 241   bool has_capability = myThread->is_VM_thread() ||
 242                         myThread->is_ConcurrentGC_thread() ||
 243                         myThread->is_GC_task_thread();
 244 
 245   if (!has_capability) {
 246     if (!VerifyStack && !VerifyLastFrame) {
 247       // verify stack calls this outside VM thread
 248       warning("oopmap should only be accessed by the "
 249               "VM, GC task or CMS threads (or during debugging)");
 250       InterpreterOopMap local_mask;
 251       method_holder()->mask_for(h_this, bci, &local_mask);
 252       local_mask.print();
 253     }
 254   }
 255 #endif
 256   method_holder()->mask_for(h_this, bci, mask);
 257   return;
 258 }
 259 
 260 
 261 int Method::bci_from(address bcp) const {
 262 #ifdef ASSERT
 263   { ResourceMark rm;
 264   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 265          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 266   }
 267 #endif
 268   return bcp - code_base();
 269 }
 270 
 271 
 272 // Return (int)bcx if it appears to be a valid BCI.
 273 // Return bci_from((address)bcx) if it appears to be a valid BCP.
 274 // Return -1 otherwise.
 275 // Used by profiling code, when invalid data is a possibility.
 276 // The caller is responsible for validating the Method* itself.
 277 int Method::validate_bci_from_bcx(intptr_t bcx) const {
 278   // keep bci as -1 if not a valid bci
 279   int bci = -1;
 280   if (bcx == 0 || (address)bcx == code_base()) {
 281     // code_size() may return 0 and we allow 0 here
 282     // the method may be native
 283     bci = 0;
 284   } else if (frame::is_bci(bcx)) {
 285     if (bcx < code_size()) {
 286       bci = (int)bcx;
 287     }
 288   } else if (contains((address)bcx)) {
 289     bci = (address)bcx - code_base();
 290   }
 291   // Assert that if we have dodged any asserts, bci is negative.
 292   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 293   return bci;
 294 }
 295 
 296 address Method::bcp_from(int bci) const {
 297   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), "illegal bci");
 298   address bcp = code_base() + bci;
 299   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 300   return bcp;
 301 }
 302 
 303 
 304 int Method::size(bool is_native) {
 305   // If native, then include pointers for native_function and signature_handler
 306   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 307   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 308   return align_object_size(header_size() + extra_words);
 309 }
 310 
 311 
 312 Symbol* Method::klass_name() const {
 313   Klass* k = method_holder();
 314   assert(k->is_klass(), "must be klass");
 315   InstanceKlass* ik = (InstanceKlass*) k;
 316   return ik->name();
 317 }
 318 
 319 
 320 void Method::set_interpreter_kind() {
 321   int kind = Interpreter::method_kind(this);
 322   assert(kind != Interpreter::invalid,
 323          "interpreter entry must be valid");
 324   set_interpreter_kind(kind);
 325 }
 326 
 327 
 328 // Attempt to return method oop to original state.  Clear any pointers
 329 // (to objects outside the shared spaces).  We won't be able to predict
 330 // where they should point in a new JVM.  Further initialize some
 331 // entries now in order allow them to be write protected later.
 332 
 333 void Method::remove_unshareable_info() {
 334   unlink_method();
 335   set_interpreter_kind();
 336 }
 337 
 338 
 339 bool Method::was_executed_more_than(int n) {
 340   // Invocation counter is reset when the Method* is compiled.
 341   // If the method has compiled code we therefore assume it has
 342   // be excuted more than n times.
 343   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 344     // interpreter doesn't bump invocation counter of trivial methods
 345     // compiler does not bump invocation counter of compiled methods
 346     return true;
 347   }
 348   else if (_invocation_counter.carry() || (method_data() != NULL && method_data()->invocation_counter()->carry())) {
 349     // The carry bit is set when the counter overflows and causes
 350     // a compilation to occur.  We don't know how many times
 351     // the counter has been reset, so we simply assume it has
 352     // been executed more than n times.
 353     return true;
 354   } else {
 355     return invocation_count() > n;
 356   }
 357 }
 358 
 359 #ifndef PRODUCT
 360 void Method::print_invocation_count() {
 361   if (is_static()) tty->print("static ");
 362   if (is_final()) tty->print("final ");
 363   if (is_synchronized()) tty->print("synchronized ");
 364   if (is_native()) tty->print("native ");
 365   method_holder()->name()->print_symbol_on(tty);
 366   tty->print(".");
 367   name()->print_symbol_on(tty);
 368   signature()->print_symbol_on(tty);
 369 
 370   if (WizardMode) {
 371     // dump the size of the byte codes
 372     tty->print(" {%d}", code_size());
 373   }
 374   tty->cr();
 375 
 376   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 377   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 378   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 379   if (CountCompiledCalls) {
 380     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 381   }
 382 
 383 }
 384 #endif
 385 
 386 // Build a MethodData* object to hold information about this method
 387 // collected in the interpreter.
 388 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 389   // Do not profile method if current thread holds the pending list lock,
 390   // which avoids deadlock for acquiring the MethodData_lock.
 391   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 392     return;
 393   }
 394 
 395   // Grab a lock here to prevent multiple
 396   // MethodData*s from being created.
 397   MutexLocker ml(MethodData_lock, THREAD);
 398   if (method->method_data() == NULL) {
 399     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 400     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 401     method->set_method_data(method_data);
 402     if (PrintMethodData && (Verbose || WizardMode)) {
 403       ResourceMark rm(THREAD);
 404       tty->print("build_interpreter_method_data for ");
 405       method->print_name(tty);
 406       tty->cr();
 407       // At the end of the run, the MDO, full of data, will be dumped.
 408     }
 409   }
 410 }
 411 
 412 void Method::cleanup_inline_caches() {
 413   // The current system doesn't use inline caches in the interpreter
 414   // => nothing to do (keep this method around for future use)
 415 }
 416 
 417 
 418 int Method::extra_stack_words() {
 419   // not an inline function, to avoid a header dependency on Interpreter
 420   return extra_stack_entries() * Interpreter::stackElementSize;
 421 }
 422 
 423 
 424 void Method::compute_size_of_parameters(Thread *thread) {
 425   ArgumentSizeComputer asc(signature());
 426   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 427 }
 428 
 429 #ifdef CC_INTERP
 430 void Method::set_result_index(BasicType type)          {
 431   _result_index = Interpreter::BasicType_as_index(type);
 432 }
 433 #endif
 434 
 435 BasicType Method::result_type() const {
 436   ResultTypeFinder rtf(signature());
 437   return rtf.type();
 438 }
 439 
 440 
 441 bool Method::is_empty_method() const {
 442   return  code_size() == 1
 443       && *code_base() == Bytecodes::_return;
 444 }
 445 
 446 
 447 bool Method::is_vanilla_constructor() const {
 448   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 449   // which only calls the superclass vanilla constructor and possibly does stores of
 450   // zero constants to local fields:
 451   //
 452   //   aload_0
 453   //   invokespecial
 454   //   indexbyte1
 455   //   indexbyte2
 456   //
 457   // followed by an (optional) sequence of:
 458   //
 459   //   aload_0
 460   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 461   //   putfield
 462   //   indexbyte1
 463   //   indexbyte2
 464   //
 465   // followed by:
 466   //
 467   //   return
 468 
 469   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 470   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 471   int size = code_size();
 472   // Check if size match
 473   if (size == 0 || size % 5 != 0) return false;
 474   address cb = code_base();
 475   int last = size - 1;
 476   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 477     // Does not call superclass default constructor
 478     return false;
 479   }
 480   // Check optional sequence
 481   for (int i = 4; i < last; i += 5) {
 482     if (cb[i] != Bytecodes::_aload_0) return false;
 483     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 484     if (cb[i+2] != Bytecodes::_putfield) return false;
 485   }
 486   return true;
 487 }
 488 
 489 
 490 bool Method::compute_has_loops_flag() {
 491   BytecodeStream bcs(this);
 492   Bytecodes::Code bc;
 493 
 494   while ((bc = bcs.next()) >= 0) {
 495     switch( bc ) {
 496       case Bytecodes::_ifeq:
 497       case Bytecodes::_ifnull:
 498       case Bytecodes::_iflt:
 499       case Bytecodes::_ifle:
 500       case Bytecodes::_ifne:
 501       case Bytecodes::_ifnonnull:
 502       case Bytecodes::_ifgt:
 503       case Bytecodes::_ifge:
 504       case Bytecodes::_if_icmpeq:
 505       case Bytecodes::_if_icmpne:
 506       case Bytecodes::_if_icmplt:
 507       case Bytecodes::_if_icmpgt:
 508       case Bytecodes::_if_icmple:
 509       case Bytecodes::_if_icmpge:
 510       case Bytecodes::_if_acmpeq:
 511       case Bytecodes::_if_acmpne:
 512       case Bytecodes::_goto:
 513       case Bytecodes::_jsr:
 514         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 515         break;
 516 
 517       case Bytecodes::_goto_w:
 518       case Bytecodes::_jsr_w:
 519         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 520         break;
 521     }
 522   }
 523   _access_flags.set_loops_flag_init();
 524   return _access_flags.has_loops();
 525 }
 526 
 527 
 528 bool Method::is_final_method() const {
 529   // %%% Should return true for private methods also,
 530   // since there is no way to override them.
 531   return is_final() || method_holder()->is_final();
 532 }
 533 
 534 
 535 bool Method::is_strict_method() const {
 536   return is_strict();
 537 }
 538 
 539 
 540 bool Method::can_be_statically_bound() const {
 541   if (is_final_method())  return true;
 542   return vtable_index() == nonvirtual_vtable_index;
 543 }
 544 
 545 
 546 bool Method::is_accessor() const {
 547   if (code_size() != 5) return false;
 548   if (size_of_parameters() != 1) return false;
 549   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 550   if (java_code_at(1) != Bytecodes::_getfield) return false;
 551   if (java_code_at(4) != Bytecodes::_areturn &&
 552       java_code_at(4) != Bytecodes::_ireturn ) return false;
 553   return true;
 554 }
 555 
 556 
 557 bool Method::is_initializer() const {
 558   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 559 }
 560 
 561 bool Method::has_valid_initializer_flags() const {
 562   return (is_static() ||
 563           method_holder()->major_version() < 51);
 564 }
 565 
 566 bool Method::is_static_initializer() const {
 567   // For classfiles version 51 or greater, ensure that the clinit method is
 568   // static.  Non-static methods with the name "<clinit>" are not static
 569   // initializers. (older classfiles exempted for backward compatibility)
 570   return name() == vmSymbols::class_initializer_name() &&
 571          has_valid_initializer_flags();
 572 }
 573 
 574 
 575 objArrayHandle Method::resolved_checked_exceptions_impl(Method* this_oop, TRAPS) {
 576   int length = this_oop->checked_exceptions_length();
 577   if (length == 0) {  // common case
 578     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 579   } else {
 580     methodHandle h_this(THREAD, this_oop);
 581     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 582     objArrayHandle mirrors (THREAD, m_oop);
 583     for (int i = 0; i < length; i++) {
 584       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 585       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 586       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 587       mirrors->obj_at_put(i, k->java_mirror());
 588     }
 589     return mirrors;
 590   }
 591 };
 592 
 593 
 594 int Method::line_number_from_bci(int bci) const {
 595   if (bci == SynchronizationEntryBCI) bci = 0;
 596   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 597   int best_bci  =  0;
 598   int best_line = -1;
 599 
 600   if (has_linenumber_table()) {
 601     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 602     // Not necessarily sorted and not necessarily one-to-one.
 603     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 604     while (stream.read_pair()) {
 605       if (stream.bci() == bci) {
 606         // perfect match
 607         return stream.line();
 608       } else {
 609         // update best_bci/line
 610         if (stream.bci() < bci && stream.bci() >= best_bci) {
 611           best_bci  = stream.bci();
 612           best_line = stream.line();
 613         }
 614       }
 615     }
 616   }
 617   return best_line;
 618 }
 619 
 620 
 621 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 622   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 623     Thread *thread = Thread::current();
 624     Symbol* klass_name = constants()->klass_name_at(klass_index);
 625     Handle loader(thread, method_holder()->class_loader());
 626     Handle prot  (thread, method_holder()->protection_domain());
 627     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 628   } else {
 629     return true;
 630   }
 631 }
 632 
 633 
 634 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 635   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 636   if (must_be_resolved) {
 637     // Make sure klass is resolved in constantpool.
 638     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 639   }
 640   return is_klass_loaded_by_klass_index(klass_index);
 641 }
 642 
 643 
 644 void Method::set_native_function(address function, bool post_event_flag) {
 645   assert(function != NULL, "use clear_native_function to unregister natives");
 646   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 647   address* native_function = native_function_addr();
 648 
 649   // We can see racers trying to place the same native function into place. Once
 650   // is plenty.
 651   address current = *native_function;
 652   if (current == function) return;
 653   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 654       function != NULL) {
 655     // native_method_throw_unsatisfied_link_error_entry() should only
 656     // be passed when post_event_flag is false.
 657     assert(function !=
 658       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 659       "post_event_flag mis-match");
 660 
 661     // post the bind event, and possible change the bind function
 662     JvmtiExport::post_native_method_bind(this, &function);
 663   }
 664   *native_function = function;
 665   // This function can be called more than once. We must make sure that we always
 666   // use the latest registered method -> check if a stub already has been generated.
 667   // If so, we have to make it not_entrant.
 668   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 669   if (nm != NULL) {
 670     nm->make_not_entrant();
 671   }
 672 }
 673 
 674 
 675 bool Method::has_native_function() const {
 676   if (is_method_handle_intrinsic())
 677     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 678   address func = native_function();
 679   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 680 }
 681 
 682 
 683 void Method::clear_native_function() {
 684   // Note: is_method_handle_intrinsic() is allowed here.
 685   set_native_function(
 686     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 687     !native_bind_event_is_interesting);
 688   clear_code();
 689 }
 690 
 691 address Method::critical_native_function() {
 692   methodHandle mh(this);
 693   return NativeLookup::lookup_critical_entry(mh);
 694 }
 695 
 696 
 697 void Method::set_signature_handler(address handler) {
 698   address* signature_handler =  signature_handler_addr();
 699   *signature_handler = handler;
 700 }
 701 
 702 
 703 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report) {
 704   if (PrintCompilation && report) {
 705     ttyLocker ttyl;
 706     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 707     if (comp_level == CompLevel_all) {
 708       tty->print("all levels ");
 709     } else {
 710       tty->print("levels ");
 711       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 712         tty->print("%d ", i);
 713       }
 714     }
 715     this->print_short_name(tty);
 716     int size = this->code_size();
 717     if (size > 0)
 718       tty->print(" (%d bytes)", size);
 719     tty->cr();
 720   }
 721   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 722     ttyLocker ttyl;
 723     xtty->begin_elem("make_not_%scompilable thread='" UINTX_FORMAT "'",
 724                      is_osr ? "osr_" : "", os::current_thread_id());
 725     xtty->method(this);
 726     xtty->stamp();
 727     xtty->end_elem();
 728   }
 729 }
 730 
 731 bool Method::is_not_compilable(int comp_level) const {
 732   if (number_of_breakpoints() > 0)
 733     return true;
 734   if (is_method_handle_intrinsic())
 735     return !is_synthetic();  // the generated adapters must be compiled
 736   if (comp_level == CompLevel_any)
 737     return is_not_c1_compilable() || is_not_c2_compilable();
 738   if (is_c1_compile(comp_level))
 739     return is_not_c1_compilable();
 740   if (is_c2_compile(comp_level))
 741     return is_not_c2_compilable();
 742   return false;
 743 }
 744 
 745 // call this when compiler finds that this method is not compilable
 746 void Method::set_not_compilable(int comp_level, bool report) {
 747   print_made_not_compilable(comp_level, /*is_osr*/ false, report);
 748   if (comp_level == CompLevel_all) {
 749     set_not_c1_compilable();
 750     set_not_c2_compilable();
 751   } else {
 752     if (is_c1_compile(comp_level))
 753       set_not_c1_compilable();
 754     if (is_c2_compile(comp_level))
 755       set_not_c2_compilable();
 756   }
 757   CompilationPolicy::policy()->disable_compilation(this);
 758 }
 759 
 760 bool Method::is_not_osr_compilable(int comp_level) const {
 761   if (is_not_compilable(comp_level))
 762     return true;
 763   if (comp_level == CompLevel_any)
 764     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 765   if (is_c1_compile(comp_level))
 766     return is_not_c1_osr_compilable();
 767   if (is_c2_compile(comp_level))
 768     return is_not_c2_osr_compilable();
 769   return false;
 770 }
 771 
 772 void Method::set_not_osr_compilable(int comp_level, bool report) {
 773   print_made_not_compilable(comp_level, /*is_osr*/ true, report);
 774   if (comp_level == CompLevel_all) {
 775     set_not_c1_osr_compilable();
 776     set_not_c2_osr_compilable();
 777   } else {
 778     if (is_c1_compile(comp_level))
 779       set_not_c1_osr_compilable();
 780     if (is_c2_compile(comp_level))
 781       set_not_c2_osr_compilable();
 782   }
 783   CompilationPolicy::policy()->disable_compilation(this);
 784 }
 785 
 786 // Revert to using the interpreter and clear out the nmethod
 787 void Method::clear_code() {
 788 
 789   // this may be NULL if c2i adapters have not been made yet
 790   // Only should happen at allocate time.
 791   if (_adapter == NULL) {
 792     _from_compiled_entry    = NULL;
 793   } else {
 794     _from_compiled_entry    = _adapter->get_c2i_entry();
 795   }
 796   OrderAccess::storestore();
 797   _from_interpreted_entry = _i2i_entry;
 798   OrderAccess::storestore();
 799   _code = NULL;
 800 }
 801 
 802 // Called by class data sharing to remove any entry points (which are not shared)
 803 void Method::unlink_method() {
 804   _code = NULL;
 805   _i2i_entry = NULL;
 806   _from_interpreted_entry = NULL;
 807   if (is_native()) {
 808     *native_function_addr() = NULL;
 809     set_signature_handler(NULL);
 810   }
 811   NOT_PRODUCT(set_compiled_invocation_count(0);)
 812   invocation_counter()->reset();
 813   backedge_counter()->reset();
 814   _adapter = NULL;
 815   _from_compiled_entry = NULL;
 816   assert(_method_data == NULL, "unexpected method data?");
 817   set_method_data(NULL);
 818   set_interpreter_throwout_count(0);
 819   set_interpreter_invocation_count(0);
 820 }
 821 
 822 // Called when the method_holder is getting linked. Setup entrypoints so the method
 823 // is ready to be called from interpreter, compiler, and vtables.
 824 void Method::link_method(methodHandle h_method, TRAPS) {
 825   // If the code cache is full, we may reenter this function for the
 826   // leftover methods that weren't linked.
 827   if (_i2i_entry != NULL) return;
 828 
 829   assert(_adapter == NULL, "init'd to NULL" );
 830   assert( _code == NULL, "nothing compiled yet" );
 831 
 832   // Setup interpreter entrypoint
 833   assert(this == h_method(), "wrong h_method()" );
 834   address entry = Interpreter::entry_for_method(h_method);
 835   assert(entry != NULL, "interpreter entry must be non-null");
 836   // Sets both _i2i_entry and _from_interpreted_entry
 837   set_interpreter_entry(entry);
 838   if (is_native() && !is_method_handle_intrinsic()) {
 839     set_native_function(
 840       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 841       !native_bind_event_is_interesting);
 842   }
 843 
 844   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 845   // special handling of vtables.  An alternative is to make adapters more
 846   // lazily by calling make_adapter() from from_compiled_entry() for the
 847   // normal calls.  For vtable calls life gets more complicated.  When a
 848   // call-site goes mega-morphic we need adapters in all methods which can be
 849   // called from the vtable.  We need adapters on such methods that get loaded
 850   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 851   // problem we'll make these lazily later.
 852   (void) make_adapters(h_method, CHECK);
 853 
 854   // ONLY USE the h_method now as make_adapter may have blocked
 855 
 856 }
 857 
 858 address Method::make_adapters(methodHandle mh, TRAPS) {
 859   // Adapters for compiled code are made eagerly here.  They are fairly
 860   // small (generally < 100 bytes) and quick to make (and cached and shared)
 861   // so making them eagerly shouldn't be too expensive.
 862   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 863   if (adapter == NULL ) {
 864     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 865   }
 866 
 867   mh->set_adapter_entry(adapter);
 868   mh->_from_compiled_entry = adapter->get_c2i_entry();
 869   return adapter->get_c2i_entry();
 870 }
 871 
 872 // The verified_code_entry() must be called when a invoke is resolved
 873 // on this method.
 874 
 875 // It returns the compiled code entry point, after asserting not null.
 876 // This function is called after potential safepoints so that nmethod
 877 // or adapter that it points to is still live and valid.
 878 // This function must not hit a safepoint!
 879 address Method::verified_code_entry() {
 880   debug_only(No_Safepoint_Verifier nsv;)
 881   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 882   if (code == NULL && UseCodeCacheFlushing) {
 883     nmethod *saved_code = CodeCache::find_and_remove_saved_code(this);
 884     if (saved_code != NULL) {
 885       methodHandle method(this);
 886       assert( ! saved_code->is_osr_method(), "should not get here for osr" );
 887       set_code( method, saved_code );
 888     }
 889   }
 890 
 891   assert(_from_compiled_entry != NULL, "must be set");
 892   return _from_compiled_entry;
 893 }
 894 
 895 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 896 // (could be racing a deopt).
 897 // Not inline to avoid circular ref.
 898 bool Method::check_code() const {
 899   // cached in a register or local.  There's a race on the value of the field.
 900   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 901   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 902 }
 903 
 904 // Install compiled code.  Instantly it can execute.
 905 void Method::set_code(methodHandle mh, nmethod *code) {
 906   assert( code, "use clear_code to remove code" );
 907   assert( mh->check_code(), "" );
 908 
 909   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 910 
 911   // These writes must happen in this order, because the interpreter will
 912   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 913   // which jumps to _from_compiled_entry.
 914   mh->_code = code;             // Assign before allowing compiled code to exec
 915 
 916   int comp_level = code->comp_level();
 917   // In theory there could be a race here. In practice it is unlikely
 918   // and not worth worrying about.
 919   if (comp_level > mh->highest_comp_level()) {
 920     mh->set_highest_comp_level(comp_level);
 921   }
 922 
 923   OrderAccess::storestore();
 924 #ifdef SHARK
 925   mh->_from_interpreted_entry = code->insts_begin();
 926 #else //!SHARK
 927   mh->_from_compiled_entry = code->verified_entry_point();
 928   OrderAccess::storestore();
 929   // Instantly compiled code can execute.
 930   if (!mh->is_method_handle_intrinsic())
 931     mh->_from_interpreted_entry = mh->get_i2c_entry();
 932 #endif //!SHARK
 933 }
 934 
 935 
 936 bool Method::is_overridden_in(Klass* k) const {
 937   InstanceKlass* ik = InstanceKlass::cast(k);
 938 
 939   if (ik->is_interface()) return false;
 940 
 941   // If method is an interface, we skip it - except if it
 942   // is a miranda method
 943   if (method_holder()->is_interface()) {
 944     // Check that method is not a miranda method
 945     if (ik->lookup_method(name(), signature()) == NULL) {
 946       // No implementation exist - so miranda method
 947       return false;
 948     }
 949     return true;
 950   }
 951 
 952   assert(ik->is_subclass_of(method_holder()), "should be subklass");
 953   assert(ik->vtable() != NULL, "vtable should exist");
 954   if (vtable_index() == nonvirtual_vtable_index) {
 955     return false;
 956   } else {
 957     Method* vt_m = ik->method_at_vtable(vtable_index());
 958     return vt_m != this;
 959   }
 960 }
 961 
 962 
 963 // give advice about whether this Method* should be cached or not
 964 bool Method::should_not_be_cached() const {
 965   if (is_old()) {
 966     // This method has been redefined. It is either EMCP or obsolete
 967     // and we don't want to cache it because that would pin the method
 968     // down and prevent it from being collectible if and when it
 969     // finishes executing.
 970     return true;
 971   }
 972 
 973   // caching this method should be just fine
 974   return false;
 975 }
 976 
 977 // Constant pool structure for invoke methods:
 978 enum {
 979   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
 980   _imcp_invoke_signature,       // utf8: (variable Symbol*)
 981   _imcp_limit
 982 };
 983 
 984 // Test if this method is an MH adapter frame generated by Java code.
 985 // Cf. java/lang/invoke/InvokerBytecodeGenerator
 986 bool Method::is_compiled_lambda_form() const {
 987   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
 988 }
 989 
 990 // Test if this method is an internal MH primitive method.
 991 bool Method::is_method_handle_intrinsic() const {
 992   vmIntrinsics::ID iid = intrinsic_id();
 993   return (MethodHandles::is_signature_polymorphic(iid) &&
 994           MethodHandles::is_signature_polymorphic_intrinsic(iid));
 995 }
 996 
 997 bool Method::has_member_arg() const {
 998   vmIntrinsics::ID iid = intrinsic_id();
 999   return (MethodHandles::is_signature_polymorphic(iid) &&
1000           MethodHandles::has_member_arg(iid));
1001 }
1002 
1003 // Make an instance of a signature-polymorphic internal MH primitive.
1004 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1005                                                          Symbol* signature,
1006                                                          TRAPS) {
1007   ResourceMark rm;
1008   methodHandle empty;
1009 
1010   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1011   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1012   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1013   if (TraceMethodHandles) {
1014     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1015   }
1016 
1017   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1018   name->increment_refcount();
1019   signature->increment_refcount();
1020 
1021   int cp_length = _imcp_limit;
1022   ClassLoaderData* loader_data = holder->class_loader_data();
1023   constantPoolHandle cp;
1024   {
1025     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1026     cp = constantPoolHandle(THREAD, cp_oop);
1027   }
1028   cp->set_pool_holder(InstanceKlass::cast(holder()));
1029   cp->symbol_at_put(_imcp_invoke_name,       name);
1030   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1031   cp->set_has_preresolution();
1032 
1033   // decide on access bits:  public or not?
1034   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1035   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1036   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1037   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1038 
1039   methodHandle m;
1040   {
1041     Method* m_oop = Method::allocate(loader_data, 0,
1042                                      accessFlags_from(flags_bits),
1043                                      0, 0, 0, 0, 0, 0,
1044                                      ConstMethod::NORMAL, CHECK_(empty));
1045     m = methodHandle(THREAD, m_oop);
1046   }
1047   m->set_constants(cp());
1048   m->set_name_index(_imcp_invoke_name);
1049   m->set_signature_index(_imcp_invoke_signature);
1050   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1051   assert(m->signature() == signature, "");
1052 #ifdef CC_INTERP
1053   ResultTypeFinder rtf(signature);
1054   m->set_result_index(rtf.type());
1055 #endif
1056   m->compute_size_of_parameters(THREAD);
1057   m->init_intrinsic_id();
1058   assert(m->is_method_handle_intrinsic(), "");
1059 #ifdef ASSERT
1060   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1061   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1062   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1063 #endif //ASSERT
1064 
1065   // Finally, set up its entry points.
1066   assert(m->can_be_statically_bound(), "");
1067   m->set_vtable_index(Method::nonvirtual_vtable_index);
1068   m->link_method(m, CHECK_(empty));
1069 
1070   if (TraceMethodHandles && (Verbose || WizardMode))
1071     m->print_on(tty);
1072 
1073   return m;
1074 }
1075 
1076 Klass* Method::check_non_bcp_klass(Klass* klass) {
1077   if (klass != NULL && klass->class_loader() != NULL) {
1078     if (klass->oop_is_objArray())
1079       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1080     return klass;
1081   }
1082   return NULL;
1083 }
1084 
1085 
1086 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1087                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1088   // Code below does not work for native methods - they should never get rewritten anyway
1089   assert(!m->is_native(), "cannot rewrite native methods");
1090   // Allocate new Method*
1091   AccessFlags flags = m->access_flags();
1092   u2  generic_signature_index = m->generic_signature_index();
1093   int checked_exceptions_len = m->checked_exceptions_length();
1094   int localvariable_len = m->localvariable_table_length();
1095   int exception_table_len = m->exception_table_length();
1096   int method_parameters_len = m->method_parameters_length();
1097 
1098   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1099   Method* newm_oop = Method::allocate(loader_data,
1100                                       new_code_length,
1101                                       flags,
1102                                       new_compressed_linenumber_size,
1103                                       localvariable_len,
1104                                       exception_table_len,
1105                                       checked_exceptions_len,
1106                                       method_parameters_len,
1107                                       generic_signature_index,
1108                                       m->method_type(),
1109                                       CHECK_(methodHandle()));
1110   methodHandle newm (THREAD, newm_oop);
1111   int new_method_size = newm->method_size();
1112 
1113   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1114   ConstMethod* newcm = newm->constMethod();
1115   int new_const_method_size = newm->constMethod()->size();
1116 
1117   memcpy(newm(), m(), sizeof(Method));
1118 
1119   // Create shallow copy of ConstMethod.
1120   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1121 
1122   // Reset correct method/const method, method size, and parameter info
1123   newm->set_constMethod(newcm);
1124   newm->constMethod()->set_code_size(new_code_length);
1125   newm->constMethod()->set_constMethod_size(new_const_method_size);
1126   newm->set_method_size(new_method_size);
1127   assert(newm->code_size() == new_code_length, "check");
1128   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1129   assert(newm->exception_table_length() == exception_table_len, "check");
1130   assert(newm->localvariable_table_length() == localvariable_len, "check");
1131   // Copy new byte codes
1132   memcpy(newm->code_base(), new_code, new_code_length);
1133   // Copy line number table
1134   if (new_compressed_linenumber_size > 0) {
1135     memcpy(newm->compressed_linenumber_table(),
1136            new_compressed_linenumber_table,
1137            new_compressed_linenumber_size);
1138   }
1139   // Copy checked_exceptions
1140   if (checked_exceptions_len > 0) {
1141     memcpy(newm->checked_exceptions_start(),
1142            m->checked_exceptions_start(),
1143            checked_exceptions_len * sizeof(CheckedExceptionElement));
1144   }
1145   // Copy exception table
1146   if (exception_table_len > 0) {
1147     memcpy(newm->exception_table_start(),
1148            m->exception_table_start(),
1149            exception_table_len * sizeof(ExceptionTableElement));
1150   }
1151   // Copy local variable number table
1152   if (localvariable_len > 0) {
1153     memcpy(newm->localvariable_table_start(),
1154            m->localvariable_table_start(),
1155            localvariable_len * sizeof(LocalVariableTableElement));
1156   }
1157   // Copy stackmap table
1158   if (m->has_stackmap_table()) {
1159     int code_attribute_length = m->stackmap_data()->length();
1160     Array<u1>* stackmap_data =
1161       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1162     memcpy((void*)stackmap_data->adr_at(0),
1163            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1164     newm->set_stackmap_data(stackmap_data);
1165   }
1166 
1167   return newm;
1168 }
1169 
1170 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1171   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1172   // because we are not loading from core libraries
1173   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1174   // which does not use the class default class loader so we check for its loader here
1175   if ((InstanceKlass::cast(holder)->class_loader() != NULL) &&
1176        InstanceKlass::cast(holder)->class_loader()->klass()->name() != vmSymbols::sun_misc_Launcher_ExtClassLoader()) {
1177     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1178   }
1179 
1180   // see if the klass name is well-known:
1181   Symbol* klass_name = InstanceKlass::cast(holder)->name();
1182   return vmSymbols::find_sid(klass_name);
1183 }
1184 
1185 void Method::init_intrinsic_id() {
1186   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1187   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1188   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1189   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1190 
1191   // the klass name is well-known:
1192   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1193   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1194 
1195   // ditto for method and signature:
1196   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1197   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1198       && name_id == vmSymbols::NO_SID)
1199     return;
1200   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1201   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1202       && sig_id == vmSymbols::NO_SID)  return;
1203   jshort flags = access_flags().as_short();
1204 
1205   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1206   if (id != vmIntrinsics::_none) {
1207     set_intrinsic_id(id);
1208     return;
1209   }
1210 
1211   // A few slightly irregular cases:
1212   switch (klass_id) {
1213   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1214     // Second chance: check in regular Math.
1215     switch (name_id) {
1216     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1217     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1218     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1219       // pretend it is the corresponding method in the non-strict class:
1220       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1221       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1222       break;
1223     }
1224     break;
1225 
1226   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1227   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1228     if (!is_native())  break;
1229     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1230     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1231       id = vmIntrinsics::_none;
1232     break;
1233   }
1234 
1235   if (id != vmIntrinsics::_none) {
1236     // Set up its iid.  It is an alias method.
1237     set_intrinsic_id(id);
1238     return;
1239   }
1240 }
1241 
1242 // These two methods are static since a GC may move the Method
1243 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1244   if (THREAD->is_Compiler_thread()) {
1245     // There is nothing useful this routine can do from within the Compile thread.
1246     // Hopefully, the signature contains only well-known classes.
1247     // We could scan for this and return true/false, but the caller won't care.
1248     return false;
1249   }
1250   bool sig_is_loaded = true;
1251   Handle class_loader(THREAD, m->method_holder()->class_loader());
1252   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1253   ResourceMark rm(THREAD);
1254   Symbol*  signature = m->signature();
1255   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1256     if (ss.is_object()) {
1257       Symbol* sym = ss.as_symbol(CHECK_(false));
1258       Symbol*  name  = sym;
1259       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1260                                              protection_domain, THREAD);
1261       // We are loading classes eagerly. If a ClassNotFoundException or
1262       // a LinkageError was generated, be sure to ignore it.
1263       if (HAS_PENDING_EXCEPTION) {
1264         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1265             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1266           CLEAR_PENDING_EXCEPTION;
1267         } else {
1268           return false;
1269         }
1270       }
1271       if( klass == NULL) { sig_is_loaded = false; }
1272     }
1273   }
1274   return sig_is_loaded;
1275 }
1276 
1277 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1278   Handle class_loader(THREAD, m->method_holder()->class_loader());
1279   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1280   ResourceMark rm(THREAD);
1281   Symbol*  signature = m->signature();
1282   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1283     if (ss.type() == T_OBJECT) {
1284       Symbol* name = ss.as_symbol_or_null();
1285       if (name == NULL) return true;
1286       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1287       if (klass == NULL) return true;
1288     }
1289   }
1290   return false;
1291 }
1292 
1293 // Exposed so field engineers can debug VM
1294 void Method::print_short_name(outputStream* st) {
1295   ResourceMark rm;
1296 #ifdef PRODUCT
1297   st->print(" %s::", method_holder()->external_name());
1298 #else
1299   st->print(" %s::", method_holder()->internal_name());
1300 #endif
1301   name()->print_symbol_on(st);
1302   if (WizardMode) signature()->print_symbol_on(st);
1303   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1304     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1305 }
1306 
1307 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1308 static void reorder_based_on_method_index(Array<Method*>* methods,
1309                                           Array<AnnotationArray*>* annotations,
1310                                           GrowableArray<AnnotationArray*>* temp_array) {
1311   if (annotations == NULL) {
1312     return;
1313   }
1314 
1315   int length = methods->length();
1316   int i;
1317   // Copy to temp array
1318   temp_array->clear();
1319   for (i = 0; i < length; i++) {
1320     temp_array->append(annotations->at(i));
1321   }
1322 
1323   // Copy back using old method indices
1324   for (i = 0; i < length; i++) {
1325     Method* m = methods->at(i);
1326     annotations->at_put(i, temp_array->at(m->method_idnum()));
1327   }
1328 }
1329 
1330 // Comparer for sorting an object array containing
1331 // Method*s.
1332 static int method_comparator(Method* a, Method* b) {
1333   return a->name()->fast_compare(b->name());
1334 }
1335 
1336 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1337 void Method::sort_methods(Array<Method*>* methods,
1338                                  Array<AnnotationArray*>* methods_annotations,
1339                                  Array<AnnotationArray*>* methods_parameter_annotations,
1340                                  Array<AnnotationArray*>* methods_default_annotations,
1341                                  Array<AnnotationArray*>* methods_type_annotations,
1342                                  bool idempotent) {
1343   int length = methods->length();
1344   if (length > 1) {
1345     bool do_annotations = false;
1346     if (methods_annotations != NULL ||
1347         methods_parameter_annotations != NULL ||
1348         methods_default_annotations != NULL ||
1349         methods_type_annotations != NULL) {
1350       do_annotations = true;
1351     }
1352     if (do_annotations) {
1353       // Remember current method ordering so we can reorder annotations
1354       for (int i = 0; i < length; i++) {
1355         Method* m = methods->at(i);
1356         m->set_method_idnum(i);
1357       }
1358     }
1359     {
1360       No_Safepoint_Verifier nsv;
1361       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1362     }
1363 
1364     // Sort annotations if necessary
1365     assert(methods_annotations == NULL           || methods_annotations->length() == methods->length(), "");
1366     assert(methods_parameter_annotations == NULL || methods_parameter_annotations->length() == methods->length(), "");
1367     assert(methods_default_annotations == NULL   || methods_default_annotations->length() == methods->length(), "");
1368     assert(methods_type_annotations == NULL   || methods_type_annotations->length() == methods->length(), "");
1369     if (do_annotations) {
1370       ResourceMark rm;
1371       // Allocate temporary storage
1372       GrowableArray<AnnotationArray*>* temp_array = new GrowableArray<AnnotationArray*>(length);
1373       reorder_based_on_method_index(methods, methods_annotations, temp_array);
1374       reorder_based_on_method_index(methods, methods_parameter_annotations, temp_array);
1375       reorder_based_on_method_index(methods, methods_default_annotations, temp_array);
1376       reorder_based_on_method_index(methods, methods_type_annotations, temp_array);
1377     }
1378 
1379     // Reset method ordering
1380     for (int i = 0; i < length; i++) {
1381       Method* m = methods->at(i);
1382       m->set_method_idnum(i);
1383     }
1384   }
1385 }
1386 
1387 
1388 class SignatureTypePrinter : public SignatureTypeNames {
1389  private:
1390   outputStream* _st;
1391   bool _use_separator;
1392 
1393   void type_name(const char* name) {
1394     if (_use_separator) _st->print(", ");
1395     _st->print(name);
1396     _use_separator = true;
1397   }
1398 
1399  public:
1400   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1401     _st = st;
1402     _use_separator = false;
1403   }
1404 
1405   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1406   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1407 };
1408 
1409 
1410 void Method::print_name(outputStream* st) {
1411   Thread *thread = Thread::current();
1412   ResourceMark rm(thread);
1413   SignatureTypePrinter sig(signature(), st);
1414   st->print("%s ", is_static() ? "static" : "virtual");
1415   sig.print_returntype();
1416   st->print(" %s.", method_holder()->internal_name());
1417   name()->print_symbol_on(st);
1418   st->print("(");
1419   sig.print_parameters();
1420   st->print(")");
1421 }
1422 
1423 
1424 //-----------------------------------------------------------------------------------
1425 // Non-product code
1426 
1427 #ifndef PRODUCT
1428 void Method::print_codes_on(outputStream* st) const {
1429   print_codes_on(0, code_size(), st);
1430 }
1431 
1432 void Method::print_codes_on(int from, int to, outputStream* st) const {
1433   Thread *thread = Thread::current();
1434   ResourceMark rm(thread);
1435   methodHandle mh (thread, (Method*)this);
1436   BytecodeStream s(mh);
1437   s.set_interval(from, to);
1438   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1439   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1440 }
1441 #endif // not PRODUCT
1442 
1443 
1444 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1445 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1446 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1447 // as end-of-stream terminator.
1448 
1449 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1450   // bci and line number does not compress into single byte.
1451   // Write out escape character and use regular compression for bci and line number.
1452   write_byte((jubyte)0xFF);
1453   write_signed_int(bci_delta);
1454   write_signed_int(line_delta);
1455 }
1456 
1457 // See comment in method.hpp which explains why this exists.
1458 #if defined(_M_AMD64) && _MSC_VER >= 1400
1459 #pragma optimize("", off)
1460 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1461   write_pair_inline(bci, line);
1462 }
1463 #pragma optimize("", on)
1464 #endif
1465 
1466 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1467   _bci = 0;
1468   _line = 0;
1469 };
1470 
1471 
1472 bool CompressedLineNumberReadStream::read_pair() {
1473   jubyte next = read_byte();
1474   // Check for terminator
1475   if (next == 0) return false;
1476   if (next == 0xFF) {
1477     // Escape character, regular compression used
1478     _bci  += read_signed_int();
1479     _line += read_signed_int();
1480   } else {
1481     // Single byte compression used
1482     _bci  += next >> 3;
1483     _line += next & 0x7;
1484   }
1485   return true;
1486 }
1487 
1488 
1489 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1490   BreakpointInfo* bp = method_holder()->breakpoints();
1491   for (; bp != NULL; bp = bp->next()) {
1492     if (bp->match(this, bci)) {
1493       return bp->orig_bytecode();
1494     }
1495   }
1496   ShouldNotReachHere();
1497   return Bytecodes::_shouldnotreachhere;
1498 }
1499 
1500 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1501   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1502   BreakpointInfo* bp = method_holder()->breakpoints();
1503   for (; bp != NULL; bp = bp->next()) {
1504     if (bp->match(this, bci)) {
1505       bp->set_orig_bytecode(code);
1506       // and continue, in case there is more than one
1507     }
1508   }
1509 }
1510 
1511 void Method::set_breakpoint(int bci) {
1512   InstanceKlass* ik = method_holder();
1513   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1514   bp->set_next(ik->breakpoints());
1515   ik->set_breakpoints(bp);
1516   // do this last:
1517   bp->set(this);
1518 }
1519 
1520 static void clear_matches(Method* m, int bci) {
1521   InstanceKlass* ik = m->method_holder();
1522   BreakpointInfo* prev_bp = NULL;
1523   BreakpointInfo* next_bp;
1524   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1525     next_bp = bp->next();
1526     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1527     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1528       // do this first:
1529       bp->clear(m);
1530       // unhook it
1531       if (prev_bp != NULL)
1532         prev_bp->set_next(next_bp);
1533       else
1534         ik->set_breakpoints(next_bp);
1535       delete bp;
1536       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1537       // at same location. So we have multiple matching (method_index and bci)
1538       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1539       // breakpoint for clear_breakpoint request and keep all other method versions
1540       // BreakpointInfo for future clear_breakpoint request.
1541       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1542       // which is being called when class is unloaded. We delete all the Breakpoint
1543       // information for all versions of method. We may not correctly restore the original
1544       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1545       // so these methods won't be used anymore.
1546       if (bci >= 0) {
1547         break;
1548       }
1549     } else {
1550       // This one is a keeper.
1551       prev_bp = bp;
1552     }
1553   }
1554 }
1555 
1556 void Method::clear_breakpoint(int bci) {
1557   assert(bci >= 0, "");
1558   clear_matches(this, bci);
1559 }
1560 
1561 void Method::clear_all_breakpoints() {
1562   clear_matches(this, -1);
1563 }
1564 
1565 
1566 int Method::invocation_count() {
1567   if (TieredCompilation) {
1568     MethodData* const mdo = method_data();
1569     if (invocation_counter()->carry() || ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1570       return InvocationCounter::count_limit;
1571     } else {
1572       return invocation_counter()->count() + ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1573     }
1574   } else {
1575     return invocation_counter()->count();
1576   }
1577 }
1578 
1579 int Method::backedge_count() {
1580   if (TieredCompilation) {
1581     MethodData* const mdo = method_data();
1582     if (backedge_counter()->carry() || ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1583       return InvocationCounter::count_limit;
1584     } else {
1585       return backedge_counter()->count() + ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1586     }
1587   } else {
1588     return backedge_counter()->count();
1589   }
1590 }
1591 
1592 int Method::highest_comp_level() const {
1593   MethodData* mdo = method_data();
1594   if (mdo != NULL) {
1595     return mdo->highest_comp_level();
1596   } else {
1597     return CompLevel_none;
1598   }
1599 }
1600 
1601 int Method::highest_osr_comp_level() const {
1602   MethodData* mdo = method_data();
1603   if (mdo != NULL) {
1604     return mdo->highest_osr_comp_level();
1605   } else {
1606     return CompLevel_none;
1607   }
1608 }
1609 
1610 void Method::set_highest_comp_level(int level) {
1611   MethodData* mdo = method_data();
1612   if (mdo != NULL) {
1613     mdo->set_highest_comp_level(level);
1614   }
1615 }
1616 
1617 void Method::set_highest_osr_comp_level(int level) {
1618   MethodData* mdo = method_data();
1619   if (mdo != NULL) {
1620     mdo->set_highest_osr_comp_level(level);
1621   }
1622 }
1623 
1624 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1625   _bci = bci;
1626   _name_index = m->name_index();
1627   _signature_index = m->signature_index();
1628   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1629   if (_orig_bytecode == Bytecodes::_breakpoint)
1630     _orig_bytecode = m->orig_bytecode_at(_bci);
1631   _next = NULL;
1632 }
1633 
1634 void BreakpointInfo::set(Method* method) {
1635 #ifdef ASSERT
1636   {
1637     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1638     if (code == Bytecodes::_breakpoint)
1639       code = method->orig_bytecode_at(_bci);
1640     assert(orig_bytecode() == code, "original bytecode must be the same");
1641   }
1642 #endif
1643   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1644   method->incr_number_of_breakpoints();
1645   SystemDictionary::notice_modification();
1646   {
1647     // Deoptimize all dependents on this method
1648     Thread *thread = Thread::current();
1649     HandleMark hm(thread);
1650     methodHandle mh(thread, method);
1651     Universe::flush_dependents_on_method(mh);
1652   }
1653 }
1654 
1655 void BreakpointInfo::clear(Method* method) {
1656   *method->bcp_from(_bci) = orig_bytecode();
1657   assert(method->number_of_breakpoints() > 0, "must not go negative");
1658   method->decr_number_of_breakpoints();
1659 }
1660 
1661 // jmethodID handling
1662 
1663 // This is a block allocating object, sort of like JNIHandleBlock, only a
1664 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1665 // deleted and so we can do some suboptimal things.
1666 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1667 // never get rid of it.
1668 // It would be nice to be able to parameterize the number of methods for
1669 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1670 // into templates.
1671 
1672 // I feel like this brain dead class should exist somewhere in the STL
1673 
1674 class JNIMethodBlock : public CHeapObj<mtClass> {
1675   enum { number_of_methods = 8 };
1676 
1677   Method*         _methods[number_of_methods];
1678   int             _top;
1679   JNIMethodBlock* _next;
1680  public:
1681   static Method* const _free_method;
1682 
1683   JNIMethodBlock() : _next(NULL), _top(0) {
1684     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1685   }
1686 
1687   Method** add_method(Method* m) {
1688     if (_top < number_of_methods) {
1689       // top points to the next free entry.
1690       int i = _top;
1691       _methods[i] = m;
1692       _top++;
1693       return &_methods[i];
1694     } else if (_top == number_of_methods) {
1695       // if the next free entry ran off the block see if there's a free entry
1696       for (int i = 0; i< number_of_methods; i++) {
1697         if (_methods[i] == _free_method) {
1698           _methods[i] = m;
1699           return &_methods[i];
1700         }
1701       }
1702       // Only check each block once for frees.  They're very unlikely.
1703       // Increment top past the end of the block.
1704       _top++;
1705     }
1706     // need to allocate a next block.
1707     if (_next == NULL) {
1708       _next = new JNIMethodBlock();
1709     }
1710     return _next->add_method(m);
1711   }
1712 
1713   bool contains(Method** m) {
1714     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1715       for (int i = 0; i< number_of_methods; i++) {
1716         if (&(b->_methods[i]) == m) {
1717           return true;
1718         }
1719       }
1720     }
1721     return false;  // not found
1722   }
1723 
1724   // Doesn't really destroy it, just marks it as free so it can be reused.
1725   void destroy_method(Method** m) {
1726 #ifdef ASSERT
1727     assert(contains(m), "should be a methodID");
1728 #endif // ASSERT
1729     *m = _free_method;
1730   }
1731 
1732   // During class unloading the methods are cleared, which is different
1733   // than freed.
1734   void clear_all_methods() {
1735     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1736       for (int i = 0; i< number_of_methods; i++) {
1737         _methods[i] = NULL;
1738       }
1739     }
1740   }
1741 #ifndef PRODUCT
1742   int count_methods() {
1743     // count all allocated methods
1744     int count = 0;
1745     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1746       for (int i = 0; i< number_of_methods; i++) {
1747         if (_methods[i] != _free_method) count++;
1748       }
1749     }
1750     return count;
1751   }
1752 #endif // PRODUCT
1753 };
1754 
1755 // Something that can't be mistaken for an address or a markOop
1756 Method* const JNIMethodBlock::_free_method = (Method*)55;
1757 
1758 // Add a method id to the jmethod_ids
1759 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1760   ClassLoaderData* cld = loader_data;
1761 
1762   if (!SafepointSynchronize::is_at_safepoint()) {
1763     // Have to add jmethod_ids() to class loader data thread-safely.
1764     // Also have to add the method to the list safely, which the cld lock
1765     // protects as well.
1766     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1767     if (cld->jmethod_ids() == NULL) {
1768       cld->set_jmethod_ids(new JNIMethodBlock());
1769     }
1770     // jmethodID is a pointer to Method*
1771     return (jmethodID)cld->jmethod_ids()->add_method(m);
1772   } else {
1773     // At safepoint, we are single threaded and can set this.
1774     if (cld->jmethod_ids() == NULL) {
1775       cld->set_jmethod_ids(new JNIMethodBlock());
1776     }
1777     // jmethodID is a pointer to Method*
1778     return (jmethodID)cld->jmethod_ids()->add_method(m);
1779   }
1780 }
1781 
1782 // Mark a jmethodID as free.  This is called when there is a data race in
1783 // InstanceKlass while creating the jmethodID cache.
1784 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1785   ClassLoaderData* cld = loader_data;
1786   Method** ptr = (Method**)m;
1787   assert(cld->jmethod_ids() != NULL, "should have method handles");
1788   cld->jmethod_ids()->destroy_method(ptr);
1789 }
1790 
1791 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1792   // Can't assert the method_holder is the same because the new method has the
1793   // scratch method holder.
1794   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1795            == new_method->method_holder()->class_loader(),
1796          "changing to a different class loader");
1797   // Just change the method in place, jmethodID pointer doesn't change.
1798   *((Method**)jmid) = new_method;
1799 }
1800 
1801 bool Method::is_method_id(jmethodID mid) {
1802   Method* m = resolve_jmethod_id(mid);
1803   assert(m != NULL, "should be called with non-null method");
1804   InstanceKlass* ik = m->method_holder();
1805   ClassLoaderData* cld = ik->class_loader_data();
1806   if (cld->jmethod_ids() == NULL) return false;
1807   return (cld->jmethod_ids()->contains((Method**)mid));
1808 }
1809 
1810 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1811   if (mid == NULL) return NULL;
1812   Method* o = resolve_jmethod_id(mid);
1813   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1814     return NULL;
1815   }
1816   return o;
1817 };
1818 
1819 void Method::set_on_stack(const bool value) {
1820   // Set both the method itself and its constant pool.  The constant pool
1821   // on stack means some method referring to it is also on the stack.
1822   _access_flags.set_on_stack(value);
1823   constants()->set_on_stack(value);
1824   if (value) MetadataOnStackMark::record(this);
1825 }
1826 
1827 // Called when the class loader is unloaded to make all methods weak.
1828 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1829   loader_data->jmethod_ids()->clear_all_methods();
1830 }
1831 
1832 
1833 // Check that this pointer is valid by checking that the vtbl pointer matches
1834 bool Method::is_valid_method() const {
1835   if (this == NULL) {
1836     return false;
1837   } else if (!is_metaspace_object()) {
1838     return false;
1839   } else {
1840     Method m;
1841     // This assumes that the vtbl pointer is the first word of a C++ object.
1842     // This assumption is also in universe.cpp patch_klass_vtble
1843     void* vtbl2 = dereference_vptr((void*)&m);
1844     void* this_vtbl = dereference_vptr((void*)this);
1845     return vtbl2 == this_vtbl;
1846   }
1847 }
1848 
1849 #ifndef PRODUCT
1850 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1851   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1852 }
1853 #endif // PRODUCT
1854 
1855 
1856 // Printing
1857 
1858 #ifndef PRODUCT
1859 
1860 void Method::print_on(outputStream* st) const {
1861   ResourceMark rm;
1862   assert(is_method(), "must be method");
1863   st->print_cr(internal_name());
1864   // get the effect of PrintOopAddress, always, for methods:
1865   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1866   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1867   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1868   constants()->print_value_on(st); st->cr();
1869   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1870   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1871   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1872   st->print_cr(" - max stack:         %d",   max_stack());
1873   st->print_cr(" - max locals:        %d",   max_locals());
1874   st->print_cr(" - size of params:    %d",   size_of_parameters());
1875   st->print_cr(" - method size:       %d",   method_size());
1876   if (intrinsic_id() != vmIntrinsics::_none)
1877     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1878   if (highest_comp_level() != CompLevel_none)
1879     st->print_cr(" - highest level:     %d", highest_comp_level());
1880   st->print_cr(" - vtable index:      %d",   _vtable_index);
1881   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1882   st->print(   " - adapters:          ");
1883   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1884   if (a == NULL)
1885     st->print_cr(INTPTR_FORMAT, a);
1886   else
1887     a->print_adapter_on(st);
1888   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1889   st->print_cr(" - code size:         %d",   code_size());
1890   if (code_size() != 0) {
1891     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1892     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1893   }
1894   if (method_data() != NULL) {
1895     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1896   }
1897   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1898   if (checked_exceptions_length() > 0) {
1899     CheckedExceptionElement* table = checked_exceptions_start();
1900     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1901     if (Verbose) {
1902       for (int i = 0; i < checked_exceptions_length(); i++) {
1903         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1904       }
1905     }
1906   }
1907   if (has_linenumber_table()) {
1908     u_char* table = compressed_linenumber_table();
1909     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1910     if (Verbose) {
1911       CompressedLineNumberReadStream stream(table);
1912       while (stream.read_pair()) {
1913         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1914       }
1915     }
1916   }
1917   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1918   if (localvariable_table_length() > 0) {
1919     LocalVariableTableElement* table = localvariable_table_start();
1920     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1921     if (Verbose) {
1922       for (int i = 0; i < localvariable_table_length(); i++) {
1923         int bci = table[i].start_bci;
1924         int len = table[i].length;
1925         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1926         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
1927         int slot = table[i].slot;
1928         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
1929       }
1930     }
1931   }
1932   if (code() != NULL) {
1933     st->print   (" - compiled code: ");
1934     code()->print_value_on(st);
1935   }
1936   if (is_native()) {
1937     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
1938     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
1939   }
1940 }
1941 
1942 #endif //PRODUCT
1943 
1944 void Method::print_value_on(outputStream* st) const {
1945   assert(is_method(), "must be method");
1946   st->print_cr(internal_name());
1947   print_address_on(st);
1948   st->print(" ");
1949   name()->print_value_on(st);
1950   st->print(" ");
1951   signature()->print_value_on(st);
1952   st->print(" in ");
1953   method_holder()->print_value_on(st);
1954   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
1955   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
1956 }
1957 
1958 #if INCLUDE_SERVICES
1959 // Size Statistics
1960 void Method::collect_statistics(KlassSizeStats *sz) const {
1961   int mysize = sz->count(this);
1962   sz->_method_bytes += mysize;
1963   sz->_method_all_bytes += mysize;
1964   sz->_rw_bytes += mysize;
1965 
1966   if (constMethod()) {
1967     constMethod()->collect_statistics(sz);
1968   }
1969   if (method_data()) {
1970     method_data()->collect_statistics(sz);
1971   }
1972 }
1973 #endif // INCLUDE_SERVICES
1974 
1975 // Verification
1976 
1977 void Method::verify_on(outputStream* st) {
1978   guarantee(is_method(), "object must be method");
1979   guarantee(is_metadata(),  "should be metadata");
1980   guarantee(constants()->is_constantPool(), "should be constant pool");
1981   guarantee(constants()->is_metadata(), "should be metadata");
1982   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
1983   guarantee(constMethod()->is_metadata(), "should be metadata");
1984   MethodData* md = method_data();
1985   guarantee(md == NULL ||
1986       md->is_metadata(), "should be metadata");
1987   guarantee(md == NULL ||
1988       md->is_methodData(), "should be method data");
1989 }