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                          InlineTableSizes* sizes,
  65                          ConstMethod::MethodType method_type,
  66                          TRAPS) {
  67   assert(!access_flags.is_native() || byte_code_size == 0,
  68          "native methods should not contain byte codes");
  69   ConstMethod* cm = ConstMethod::allocate(loader_data,
  70                                           byte_code_size,
  71                                           sizes,
  72                                           method_type,
  73                                           CHECK_NULL);
  74 
  75   int size = Method::size(access_flags.is_native());
  76 
  77   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  78 }
  79 
  80 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  81   No_Safepoint_Verifier no_safepoint;
  82   set_constMethod(xconst);
  83   set_access_flags(access_flags);
  84   set_method_size(size);
  85 #ifdef CC_INTERP
  86   set_result_index(T_VOID);
  87 #endif
  88   set_intrinsic_id(vmIntrinsics::_none);
  89   set_jfr_towrite(false);
  90   set_force_inline(false);
  91   set_hidden(false);
  92   set_dont_inline(false);
  93   set_method_data(NULL);
  94   set_method_counters(NULL);
  95   set_vtable_index(Method::garbage_vtable_index);
  96 
  97   // Fix and bury in Method*
  98   set_interpreter_entry(NULL); // sets i2i entry and from_int
  99   set_adapter_entry(NULL);
 100   clear_code(); // from_c/from_i get set to c2i/i2i
 101 
 102   if (access_flags.is_native()) {
 103     clear_native_function();
 104     set_signature_handler(NULL);
 105   }
 106 
 107   NOT_PRODUCT(set_compiled_invocation_count(0);)
 108 }
 109 
 110 // Release Method*.  The nmethod will be gone when we get here because
 111 // we've walked the code cache.
 112 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 113   MetadataFactory::free_metadata(loader_data, constMethod());
 114   set_constMethod(NULL);
 115   MetadataFactory::free_metadata(loader_data, method_data());
 116   set_method_data(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_counters());
 118   set_method_counters(NULL);
 119   // The nmethod will be gone when we get here.
 120   if (code() != NULL) _code = NULL;
 121 }
 122 
 123 address Method::get_i2c_entry() {
 124   assert(_adapter != NULL, "must have");
 125   return _adapter->get_i2c_entry();
 126 }
 127 
 128 address Method::get_c2i_entry() {
 129   assert(_adapter != NULL, "must have");
 130   return _adapter->get_c2i_entry();
 131 }
 132 
 133 address Method::get_c2i_unverified_entry() {
 134   assert(_adapter != NULL, "must have");
 135   return _adapter->get_c2i_unverified_entry();
 136 }
 137 
 138 char* Method::name_and_sig_as_C_string() const {
 139   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 140 }
 141 
 142 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 143   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 144 }
 145 
 146 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 147   const char* klass_name = klass->external_name();
 148   int klass_name_len  = (int)strlen(klass_name);
 149   int method_name_len = method_name->utf8_length();
 150   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 151   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 152   strcpy(dest, klass_name);
 153   dest[klass_name_len] = '.';
 154   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 155   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 156   dest[len] = 0;
 157   return dest;
 158 }
 159 
 160 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 161   Symbol* klass_name = klass->name();
 162   klass_name->as_klass_external_name(buf, size);
 163   int len = (int)strlen(buf);
 164 
 165   if (len < size - 1) {
 166     buf[len++] = '.';
 167 
 168     method_name->as_C_string(&(buf[len]), size - len);
 169     len = (int)strlen(buf);
 170 
 171     signature->as_C_string(&(buf[len]), size - len);
 172   }
 173 
 174   return buf;
 175 }
 176 
 177 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 178   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 179   // access exception table
 180   ExceptionTable table(mh());
 181   int length = table.length();
 182   // iterate through all entries sequentially
 183   constantPoolHandle pool(THREAD, mh->constants());
 184   for (int i = 0; i < length; i ++) {
 185     //reacquire the table in case a GC happened
 186     ExceptionTable table(mh());
 187     int beg_bci = table.start_pc(i);
 188     int end_bci = table.end_pc(i);
 189     assert(beg_bci <= end_bci, "inconsistent exception table");
 190     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 191       // exception handler bci range covers throw_bci => investigate further
 192       int handler_bci = table.handler_pc(i);
 193       int klass_index = table.catch_type_index(i);
 194       if (klass_index == 0) {
 195         return handler_bci;
 196       } else if (ex_klass.is_null()) {
 197         return handler_bci;
 198       } else {
 199         // we know the exception class => get the constraint class
 200         // this may require loading of the constraint class; if verification
 201         // fails or some other exception occurs, return handler_bci
 202         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 203         KlassHandle klass = KlassHandle(THREAD, k);
 204         assert(klass.not_null(), "klass not loaded");
 205         if (ex_klass->is_subtype_of(klass())) {
 206           return handler_bci;
 207         }
 208       }
 209     }
 210   }
 211 
 212   return -1;
 213 }
 214 
 215 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 216 
 217   Thread* myThread    = Thread::current();
 218   methodHandle h_this(myThread, this);
 219 #ifdef ASSERT
 220   bool has_capability = myThread->is_VM_thread() ||
 221                         myThread->is_ConcurrentGC_thread() ||
 222                         myThread->is_GC_task_thread();
 223 
 224   if (!has_capability) {
 225     if (!VerifyStack && !VerifyLastFrame) {
 226       // verify stack calls this outside VM thread
 227       warning("oopmap should only be accessed by the "
 228               "VM, GC task or CMS threads (or during debugging)");
 229       InterpreterOopMap local_mask;
 230       method_holder()->mask_for(h_this, bci, &local_mask);
 231       local_mask.print();
 232     }
 233   }
 234 #endif
 235   method_holder()->mask_for(h_this, bci, mask);
 236   return;
 237 }
 238 
 239 
 240 int Method::bci_from(address bcp) const {
 241 #ifdef ASSERT
 242   { ResourceMark rm;
 243   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 244          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 245   }
 246 #endif
 247   return bcp - code_base();
 248 }
 249 
 250 
 251 // Return (int)bcx if it appears to be a valid BCI.
 252 // Return bci_from((address)bcx) if it appears to be a valid BCP.
 253 // Return -1 otherwise.
 254 // Used by profiling code, when invalid data is a possibility.
 255 // The caller is responsible for validating the Method* itself.
 256 int Method::validate_bci_from_bcx(intptr_t bcx) const {
 257   // keep bci as -1 if not a valid bci
 258   int bci = -1;
 259   if (bcx == 0 || (address)bcx == code_base()) {
 260     // code_size() may return 0 and we allow 0 here
 261     // the method may be native
 262     bci = 0;
 263   } else if (frame::is_bci(bcx)) {
 264     if (bcx < code_size()) {
 265       bci = (int)bcx;
 266     }
 267   } else if (contains((address)bcx)) {
 268     bci = (address)bcx - code_base();
 269   }
 270   // Assert that if we have dodged any asserts, bci is negative.
 271   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 272   return bci;
 273 }
 274 
 275 address Method::bcp_from(int bci) const {
 276   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), "illegal bci");
 277   address bcp = code_base() + bci;
 278   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 279   return bcp;
 280 }
 281 
 282 
 283 int Method::size(bool is_native) {
 284   // If native, then include pointers for native_function and signature_handler
 285   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 286   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 287   return align_object_size(header_size() + extra_words);
 288 }
 289 
 290 
 291 Symbol* Method::klass_name() const {
 292   Klass* k = method_holder();
 293   assert(k->is_klass(), "must be klass");
 294   InstanceKlass* ik = (InstanceKlass*) k;
 295   return ik->name();
 296 }
 297 
 298 
 299 // Attempt to return method oop to original state.  Clear any pointers
 300 // (to objects outside the shared spaces).  We won't be able to predict
 301 // where they should point in a new JVM.  Further initialize some
 302 // entries now in order allow them to be write protected later.
 303 
 304 void Method::remove_unshareable_info() {
 305   unlink_method();
 306 }
 307 
 308 
 309 bool Method::was_executed_more_than(int n) {
 310   // Invocation counter is reset when the Method* is compiled.
 311   // If the method has compiled code we therefore assume it has
 312   // be excuted more than n times.
 313   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 314     // interpreter doesn't bump invocation counter of trivial methods
 315     // compiler does not bump invocation counter of compiled methods
 316     return true;
 317   }
 318   else if ((method_counters() != NULL &&
 319             method_counters()->invocation_counter()->carry()) ||
 320            (method_data() != NULL &&
 321             method_data()->invocation_counter()->carry())) {
 322     // The carry bit is set when the counter overflows and causes
 323     // a compilation to occur.  We don't know how many times
 324     // the counter has been reset, so we simply assume it has
 325     // been executed more than n times.
 326     return true;
 327   } else {
 328     return invocation_count() > n;
 329   }
 330 }
 331 
 332 #ifndef PRODUCT
 333 void Method::print_invocation_count() {
 334   if (is_static()) tty->print("static ");
 335   if (is_final()) tty->print("final ");
 336   if (is_synchronized()) tty->print("synchronized ");
 337   if (is_native()) tty->print("native ");
 338   method_holder()->name()->print_symbol_on(tty);
 339   tty->print(".");
 340   name()->print_symbol_on(tty);
 341   signature()->print_symbol_on(tty);
 342 
 343   if (WizardMode) {
 344     // dump the size of the byte codes
 345     tty->print(" {%d}", code_size());
 346   }
 347   tty->cr();
 348 
 349   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 350   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 351   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 352   if (CountCompiledCalls) {
 353     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 354   }
 355 
 356 }
 357 #endif
 358 
 359 // Build a MethodData* object to hold information about this method
 360 // collected in the interpreter.
 361 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 362   // Do not profile method if current thread holds the pending list lock,
 363   // which avoids deadlock for acquiring the MethodData_lock.
 364   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 365     return;
 366   }
 367 
 368   // Grab a lock here to prevent multiple
 369   // MethodData*s from being created.
 370   MutexLocker ml(MethodData_lock, THREAD);
 371   if (method->method_data() == NULL) {
 372     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 373     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 374     method->set_method_data(method_data);
 375     if (PrintMethodData && (Verbose || WizardMode)) {
 376       ResourceMark rm(THREAD);
 377       tty->print("build_interpreter_method_data for ");
 378       method->print_name(tty);
 379       tty->cr();
 380       // At the end of the run, the MDO, full of data, will be dumped.
 381     }
 382   }
 383 }
 384 
 385 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 386   methodHandle mh(m);
 387   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
 388   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
 389   if (mh->method_counters() == NULL) {
 390     mh->set_method_counters(counters);
 391   } else {
 392     MetadataFactory::free_metadata(loader_data, counters);
 393   }
 394   return mh->method_counters();
 395 }
 396 
 397 void Method::cleanup_inline_caches() {
 398   // The current system doesn't use inline caches in the interpreter
 399   // => nothing to do (keep this method around for future use)
 400 }
 401 
 402 
 403 int Method::extra_stack_words() {
 404   // not an inline function, to avoid a header dependency on Interpreter
 405   return extra_stack_entries() * Interpreter::stackElementSize;
 406 }
 407 
 408 
 409 void Method::compute_size_of_parameters(Thread *thread) {
 410   ArgumentSizeComputer asc(signature());
 411   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 412 }
 413 
 414 #ifdef CC_INTERP
 415 void Method::set_result_index(BasicType type)          {
 416   _result_index = Interpreter::BasicType_as_index(type);
 417 }
 418 #endif
 419 
 420 BasicType Method::result_type() const {
 421   ResultTypeFinder rtf(signature());
 422   return rtf.type();
 423 }
 424 
 425 
 426 bool Method::is_empty_method() const {
 427   return  code_size() == 1
 428       && *code_base() == Bytecodes::_return;
 429 }
 430 
 431 
 432 bool Method::is_vanilla_constructor() const {
 433   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 434   // which only calls the superclass vanilla constructor and possibly does stores of
 435   // zero constants to local fields:
 436   //
 437   //   aload_0
 438   //   invokespecial
 439   //   indexbyte1
 440   //   indexbyte2
 441   //
 442   // followed by an (optional) sequence of:
 443   //
 444   //   aload_0
 445   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 446   //   putfield
 447   //   indexbyte1
 448   //   indexbyte2
 449   //
 450   // followed by:
 451   //
 452   //   return
 453 
 454   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 455   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 456   int size = code_size();
 457   // Check if size match
 458   if (size == 0 || size % 5 != 0) return false;
 459   address cb = code_base();
 460   int last = size - 1;
 461   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 462     // Does not call superclass default constructor
 463     return false;
 464   }
 465   // Check optional sequence
 466   for (int i = 4; i < last; i += 5) {
 467     if (cb[i] != Bytecodes::_aload_0) return false;
 468     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 469     if (cb[i+2] != Bytecodes::_putfield) return false;
 470   }
 471   return true;
 472 }
 473 
 474 
 475 bool Method::compute_has_loops_flag() {
 476   BytecodeStream bcs(this);
 477   Bytecodes::Code bc;
 478 
 479   while ((bc = bcs.next()) >= 0) {
 480     switch( bc ) {
 481       case Bytecodes::_ifeq:
 482       case Bytecodes::_ifnull:
 483       case Bytecodes::_iflt:
 484       case Bytecodes::_ifle:
 485       case Bytecodes::_ifne:
 486       case Bytecodes::_ifnonnull:
 487       case Bytecodes::_ifgt:
 488       case Bytecodes::_ifge:
 489       case Bytecodes::_if_icmpeq:
 490       case Bytecodes::_if_icmpne:
 491       case Bytecodes::_if_icmplt:
 492       case Bytecodes::_if_icmpgt:
 493       case Bytecodes::_if_icmple:
 494       case Bytecodes::_if_icmpge:
 495       case Bytecodes::_if_acmpeq:
 496       case Bytecodes::_if_acmpne:
 497       case Bytecodes::_goto:
 498       case Bytecodes::_jsr:
 499         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 500         break;
 501 
 502       case Bytecodes::_goto_w:
 503       case Bytecodes::_jsr_w:
 504         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 505         break;
 506     }
 507   }
 508   _access_flags.set_loops_flag_init();
 509   return _access_flags.has_loops();
 510 }
 511 
 512 
 513 bool Method::is_final_method() const {
 514   // %%% Should return true for private methods also,
 515   // since there is no way to override them.
 516   return is_final() || method_holder()->is_final();
 517 }
 518 
 519 
 520 bool Method::is_strict_method() const {
 521   return is_strict();
 522 }
 523 
 524 
 525 bool Method::can_be_statically_bound() const {
 526   if (is_final_method())  return true;
 527   return vtable_index() == nonvirtual_vtable_index;
 528 }
 529 
 530 
 531 bool Method::is_accessor() const {
 532   if (code_size() != 5) return false;
 533   if (size_of_parameters() != 1) return false;
 534   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 535   if (java_code_at(1) != Bytecodes::_getfield) return false;
 536   if (java_code_at(4) != Bytecodes::_areturn &&
 537       java_code_at(4) != Bytecodes::_ireturn ) return false;
 538   return true;
 539 }
 540 
 541 
 542 bool Method::is_initializer() const {
 543   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 544 }
 545 
 546 bool Method::has_valid_initializer_flags() const {
 547   return (is_static() ||
 548           method_holder()->major_version() < 51);
 549 }
 550 
 551 bool Method::is_static_initializer() const {
 552   // For classfiles version 51 or greater, ensure that the clinit method is
 553   // static.  Non-static methods with the name "<clinit>" are not static
 554   // initializers. (older classfiles exempted for backward compatibility)
 555   return name() == vmSymbols::class_initializer_name() &&
 556          has_valid_initializer_flags();
 557 }
 558 
 559 
 560 objArrayHandle Method::resolved_checked_exceptions_impl(Method* this_oop, TRAPS) {
 561   int length = this_oop->checked_exceptions_length();
 562   if (length == 0) {  // common case
 563     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 564   } else {
 565     methodHandle h_this(THREAD, this_oop);
 566     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 567     objArrayHandle mirrors (THREAD, m_oop);
 568     for (int i = 0; i < length; i++) {
 569       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 570       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 571       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 572       mirrors->obj_at_put(i, k->java_mirror());
 573     }
 574     return mirrors;
 575   }
 576 };
 577 
 578 
 579 int Method::line_number_from_bci(int bci) const {
 580   if (bci == SynchronizationEntryBCI) bci = 0;
 581   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 582   int best_bci  =  0;
 583   int best_line = -1;
 584 
 585   if (has_linenumber_table()) {
 586     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 587     // Not necessarily sorted and not necessarily one-to-one.
 588     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 589     while (stream.read_pair()) {
 590       if (stream.bci() == bci) {
 591         // perfect match
 592         return stream.line();
 593       } else {
 594         // update best_bci/line
 595         if (stream.bci() < bci && stream.bci() >= best_bci) {
 596           best_bci  = stream.bci();
 597           best_line = stream.line();
 598         }
 599       }
 600     }
 601   }
 602   return best_line;
 603 }
 604 
 605 
 606 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 607   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 608     Thread *thread = Thread::current();
 609     Symbol* klass_name = constants()->klass_name_at(klass_index);
 610     Handle loader(thread, method_holder()->class_loader());
 611     Handle prot  (thread, method_holder()->protection_domain());
 612     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 613   } else {
 614     return true;
 615   }
 616 }
 617 
 618 
 619 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 620   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 621   if (must_be_resolved) {
 622     // Make sure klass is resolved in constantpool.
 623     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 624   }
 625   return is_klass_loaded_by_klass_index(klass_index);
 626 }
 627 
 628 
 629 void Method::set_native_function(address function, bool post_event_flag) {
 630   assert(function != NULL, "use clear_native_function to unregister natives");
 631   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 632   address* native_function = native_function_addr();
 633 
 634   // We can see racers trying to place the same native function into place. Once
 635   // is plenty.
 636   address current = *native_function;
 637   if (current == function) return;
 638   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 639       function != NULL) {
 640     // native_method_throw_unsatisfied_link_error_entry() should only
 641     // be passed when post_event_flag is false.
 642     assert(function !=
 643       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 644       "post_event_flag mis-match");
 645 
 646     // post the bind event, and possible change the bind function
 647     JvmtiExport::post_native_method_bind(this, &function);
 648   }
 649   *native_function = function;
 650   // This function can be called more than once. We must make sure that we always
 651   // use the latest registered method -> check if a stub already has been generated.
 652   // If so, we have to make it not_entrant.
 653   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 654   if (nm != NULL) {
 655     nm->make_not_entrant();
 656   }
 657 }
 658 
 659 
 660 bool Method::has_native_function() const {
 661   if (is_method_handle_intrinsic())
 662     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 663   address func = native_function();
 664   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 665 }
 666 
 667 
 668 void Method::clear_native_function() {
 669   // Note: is_method_handle_intrinsic() is allowed here.
 670   set_native_function(
 671     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 672     !native_bind_event_is_interesting);
 673   clear_code();
 674 }
 675 
 676 address Method::critical_native_function() {
 677   methodHandle mh(this);
 678   return NativeLookup::lookup_critical_entry(mh);
 679 }
 680 
 681 
 682 void Method::set_signature_handler(address handler) {
 683   address* signature_handler =  signature_handler_addr();
 684   *signature_handler = handler;
 685 }
 686 
 687 
 688 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 689   if (PrintCompilation && report) {
 690     ttyLocker ttyl;
 691     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 692     if (comp_level == CompLevel_all) {
 693       tty->print("all levels ");
 694     } else {
 695       tty->print("levels ");
 696       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 697         tty->print("%d ", i);
 698       }
 699     }
 700     this->print_short_name(tty);
 701     int size = this->code_size();
 702     if (size > 0) {
 703       tty->print(" (%d bytes)", size);
 704     }
 705     if (reason != NULL) {
 706       tty->print("   %s", reason);
 707     }
 708     tty->cr();
 709   }
 710   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 711     ttyLocker ttyl;
 712     xtty->begin_elem("make_not_%scompilable thread='" UINTX_FORMAT "'",
 713                      is_osr ? "osr_" : "", os::current_thread_id());
 714     if (reason != NULL) {
 715       xtty->print(" reason=\'%s\'", reason);
 716     }
 717     xtty->method(this);
 718     xtty->stamp();
 719     xtty->end_elem();
 720   }
 721 }
 722 
 723 bool Method::is_not_compilable(int comp_level) const {
 724   if (number_of_breakpoints() > 0)
 725     return true;
 726   if (is_method_handle_intrinsic())
 727     return !is_synthetic();  // the generated adapters must be compiled
 728   if (comp_level == CompLevel_any)
 729     return is_not_c1_compilable() || is_not_c2_compilable();
 730   if (is_c1_compile(comp_level))
 731     return is_not_c1_compilable();
 732   if (is_c2_compile(comp_level))
 733     return is_not_c2_compilable();
 734   return false;
 735 }
 736 
 737 // call this when compiler finds that this method is not compilable
 738 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 739   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 740   if (comp_level == CompLevel_all) {
 741     set_not_c1_compilable();
 742     set_not_c2_compilable();
 743   } else {
 744     if (is_c1_compile(comp_level))
 745       set_not_c1_compilable();
 746     if (is_c2_compile(comp_level))
 747       set_not_c2_compilable();
 748   }
 749   CompilationPolicy::policy()->disable_compilation(this);
 750 }
 751 
 752 bool Method::is_not_osr_compilable(int comp_level) const {
 753   if (is_not_compilable(comp_level))
 754     return true;
 755   if (comp_level == CompLevel_any)
 756     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 757   if (is_c1_compile(comp_level))
 758     return is_not_c1_osr_compilable();
 759   if (is_c2_compile(comp_level))
 760     return is_not_c2_osr_compilable();
 761   return false;
 762 }
 763 
 764 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 765   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 766   if (comp_level == CompLevel_all) {
 767     set_not_c1_osr_compilable();
 768     set_not_c2_osr_compilable();
 769   } else {
 770     if (is_c1_compile(comp_level))
 771       set_not_c1_osr_compilable();
 772     if (is_c2_compile(comp_level))
 773       set_not_c2_osr_compilable();
 774   }
 775   CompilationPolicy::policy()->disable_compilation(this);
 776 }
 777 
 778 // Revert to using the interpreter and clear out the nmethod
 779 void Method::clear_code() {
 780 
 781   // this may be NULL if c2i adapters have not been made yet
 782   // Only should happen at allocate time.
 783   if (_adapter == NULL) {
 784     _from_compiled_entry    = NULL;
 785   } else {
 786     _from_compiled_entry    = _adapter->get_c2i_entry();
 787   }
 788   OrderAccess::storestore();
 789   _from_interpreted_entry = _i2i_entry;
 790   OrderAccess::storestore();
 791   _code = NULL;
 792 }
 793 
 794 // Called by class data sharing to remove any entry points (which are not shared)
 795 void Method::unlink_method() {
 796   _code = NULL;
 797   _i2i_entry = NULL;
 798   _from_interpreted_entry = NULL;
 799   if (is_native()) {
 800     *native_function_addr() = NULL;
 801     set_signature_handler(NULL);
 802   }
 803   NOT_PRODUCT(set_compiled_invocation_count(0);)
 804   _adapter = NULL;
 805   _from_compiled_entry = NULL;
 806 
 807   // In case of DumpSharedSpaces, _method_data should always be NULL.
 808   //
 809   // During runtime (!DumpSharedSpaces), when we are cleaning a
 810   // shared class that failed to load, this->link_method() may
 811   // have already been called (before an exception happened), so
 812   // this->_method_data may not be NULL.
 813   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 814 
 815   set_method_data(NULL);
 816   set_method_counters(NULL);
 817 }
 818 
 819 // Called when the method_holder is getting linked. Setup entrypoints so the method
 820 // is ready to be called from interpreter, compiler, and vtables.
 821 void Method::link_method(methodHandle h_method, TRAPS) {
 822   // If the code cache is full, we may reenter this function for the
 823   // leftover methods that weren't linked.
 824   if (_i2i_entry != NULL) return;
 825 
 826   assert(_adapter == NULL, "init'd to NULL" );
 827   assert( _code == NULL, "nothing compiled yet" );
 828 
 829   // Setup interpreter entrypoint
 830   assert(this == h_method(), "wrong h_method()" );
 831   address entry = Interpreter::entry_for_method(h_method);
 832   assert(entry != NULL, "interpreter entry must be non-null");
 833   // Sets both _i2i_entry and _from_interpreted_entry
 834   set_interpreter_entry(entry);
 835 
 836   // Don't overwrite already registered native entries.
 837   if (is_native() && !has_native_function()) {
 838     set_native_function(
 839       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 840       !native_bind_event_is_interesting);
 841   }
 842 
 843   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 844   // special handling of vtables.  An alternative is to make adapters more
 845   // lazily by calling make_adapter() from from_compiled_entry() for the
 846   // normal calls.  For vtable calls life gets more complicated.  When a
 847   // call-site goes mega-morphic we need adapters in all methods which can be
 848   // called from the vtable.  We need adapters on such methods that get loaded
 849   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 850   // problem we'll make these lazily later.
 851   (void) make_adapters(h_method, CHECK);
 852 
 853   // ONLY USE the h_method now as make_adapter may have blocked
 854 
 855 }
 856 
 857 address Method::make_adapters(methodHandle mh, TRAPS) {
 858   // Adapters for compiled code are made eagerly here.  They are fairly
 859   // small (generally < 100 bytes) and quick to make (and cached and shared)
 860   // so making them eagerly shouldn't be too expensive.
 861   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 862   if (adapter == NULL ) {
 863     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 864   }
 865 
 866   mh->set_adapter_entry(adapter);
 867   mh->_from_compiled_entry = adapter->get_c2i_entry();
 868   return adapter->get_c2i_entry();
 869 }
 870 
 871 // The verified_code_entry() must be called when a invoke is resolved
 872 // on this method.
 873 
 874 // It returns the compiled code entry point, after asserting not null.
 875 // This function is called after potential safepoints so that nmethod
 876 // or adapter that it points to is still live and valid.
 877 // This function must not hit a safepoint!
 878 address Method::verified_code_entry() {
 879   debug_only(No_Safepoint_Verifier nsv;)
 880   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 881   if (code == NULL && UseCodeCacheFlushing) {
 882     nmethod *saved_code = CodeCache::reanimate_saved_code(this);
 883     if (saved_code != NULL) {
 884       methodHandle method(this);
 885       assert( ! saved_code->is_osr_method(), "should not get here for osr" );
 886       set_code( method, saved_code );
 887     }
 888   }
 889 
 890   assert(_from_compiled_entry != NULL, "must be set");
 891   return _from_compiled_entry;
 892 }
 893 
 894 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 895 // (could be racing a deopt).
 896 // Not inline to avoid circular ref.
 897 bool Method::check_code() const {
 898   // cached in a register or local.  There's a race on the value of the field.
 899   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 900   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 901 }
 902 
 903 // Install compiled code.  Instantly it can execute.
 904 void Method::set_code(methodHandle mh, nmethod *code) {
 905   assert( code, "use clear_code to remove code" );
 906   assert( mh->check_code(), "" );
 907 
 908   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 909 
 910   // These writes must happen in this order, because the interpreter will
 911   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 912   // which jumps to _from_compiled_entry.
 913   mh->_code = code;             // Assign before allowing compiled code to exec
 914 
 915   int comp_level = code->comp_level();
 916   // In theory there could be a race here. In practice it is unlikely
 917   // and not worth worrying about.
 918   if (comp_level > mh->highest_comp_level()) {
 919     mh->set_highest_comp_level(comp_level);
 920   }
 921 
 922   OrderAccess::storestore();
 923 #ifdef SHARK
 924   mh->_from_interpreted_entry = code->insts_begin();
 925 #else //!SHARK
 926   mh->_from_compiled_entry = code->verified_entry_point();
 927   OrderAccess::storestore();
 928   // Instantly compiled code can execute.
 929   if (!mh->is_method_handle_intrinsic())
 930     mh->_from_interpreted_entry = mh->get_i2c_entry();
 931 #endif //!SHARK
 932 }
 933 
 934 
 935 bool Method::is_overridden_in(Klass* k) const {
 936   InstanceKlass* ik = InstanceKlass::cast(k);
 937 
 938   if (ik->is_interface()) return false;
 939 
 940   // If method is an interface, we skip it - except if it
 941   // is a miranda method
 942   if (method_holder()->is_interface()) {
 943     // Check that method is not a miranda method
 944     if (ik->lookup_method(name(), signature()) == NULL) {
 945       // No implementation exist - so miranda method
 946       return false;
 947     }
 948     return true;
 949   }
 950 
 951   assert(ik->is_subclass_of(method_holder()), "should be subklass");
 952   assert(ik->vtable() != NULL, "vtable should exist");
 953   if (vtable_index() == nonvirtual_vtable_index) {
 954     return false;
 955   } else {
 956     Method* vt_m = ik->method_at_vtable(vtable_index());
 957     return vt_m != this;
 958   }
 959 }
 960 
 961 
 962 // give advice about whether this Method* should be cached or not
 963 bool Method::should_not_be_cached() const {
 964   if (is_old()) {
 965     // This method has been redefined. It is either EMCP or obsolete
 966     // and we don't want to cache it because that would pin the method
 967     // down and prevent it from being collectible if and when it
 968     // finishes executing.
 969     return true;
 970   }
 971 
 972   // caching this method should be just fine
 973   return false;
 974 }
 975 
 976 
 977 /**
 978  *  Returns true if this is one of the specially treated methods for
 979  *  security related stack walks (like Reflection.getCallerClass).
 980  */
 981 bool Method::is_ignored_by_security_stack_walk() const {
 982   const bool use_new_reflection = JDK_Version::is_gte_jdk14x_version() && UseNewReflection;
 983 
 984   assert(intrinsic_id() != vmIntrinsics::_invoke || Universe::reflect_invoke_cache()->is_same_method((Method*)this), "sanity");
 985   if (intrinsic_id() == vmIntrinsics::_invoke) {
 986     // This is Method.invoke() -- ignore it
 987     return true;
 988   }
 989   if (use_new_reflection &&
 990       method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
 991     // This is an auxilary frame -- ignore it
 992     return true;
 993   }
 994   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
 995     // This is an internal adapter frame for method handles -- ignore it
 996     return true;
 997   }
 998   return false;
 999 }
1000 
1001 
1002 // Constant pool structure for invoke methods:
1003 enum {
1004   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1005   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1006   _imcp_limit
1007 };
1008 
1009 // Test if this method is an MH adapter frame generated by Java code.
1010 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1011 bool Method::is_compiled_lambda_form() const {
1012   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1013 }
1014 
1015 // Test if this method is an internal MH primitive method.
1016 bool Method::is_method_handle_intrinsic() const {
1017   vmIntrinsics::ID iid = intrinsic_id();
1018   return (MethodHandles::is_signature_polymorphic(iid) &&
1019           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1020 }
1021 
1022 bool Method::has_member_arg() const {
1023   vmIntrinsics::ID iid = intrinsic_id();
1024   return (MethodHandles::is_signature_polymorphic(iid) &&
1025           MethodHandles::has_member_arg(iid));
1026 }
1027 
1028 // Make an instance of a signature-polymorphic internal MH primitive.
1029 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1030                                                          Symbol* signature,
1031                                                          TRAPS) {
1032   ResourceMark rm;
1033   methodHandle empty;
1034 
1035   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1036   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1037   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1038   if (TraceMethodHandles) {
1039     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1040   }
1041 
1042   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1043   name->increment_refcount();
1044   signature->increment_refcount();
1045 
1046   int cp_length = _imcp_limit;
1047   ClassLoaderData* loader_data = holder->class_loader_data();
1048   constantPoolHandle cp;
1049   {
1050     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1051     cp = constantPoolHandle(THREAD, cp_oop);
1052   }
1053   cp->set_pool_holder(InstanceKlass::cast(holder()));
1054   cp->symbol_at_put(_imcp_invoke_name,       name);
1055   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1056   cp->set_has_preresolution();
1057 
1058   // decide on access bits:  public or not?
1059   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1060   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1061   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1062   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1063 
1064   methodHandle m;
1065   {
1066     InlineTableSizes sizes;
1067     Method* m_oop = Method::allocate(loader_data, 0,
1068                                      accessFlags_from(flags_bits), &sizes,
1069                                      ConstMethod::NORMAL, CHECK_(empty));
1070     m = methodHandle(THREAD, m_oop);
1071   }
1072   m->set_constants(cp());
1073   m->set_name_index(_imcp_invoke_name);
1074   m->set_signature_index(_imcp_invoke_signature);
1075   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1076   assert(m->signature() == signature, "");
1077 #ifdef CC_INTERP
1078   ResultTypeFinder rtf(signature);
1079   m->set_result_index(rtf.type());
1080 #endif
1081   m->compute_size_of_parameters(THREAD);
1082   m->init_intrinsic_id();
1083   assert(m->is_method_handle_intrinsic(), "");
1084 #ifdef ASSERT
1085   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1086   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1087   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1088 #endif //ASSERT
1089 
1090   // Finally, set up its entry points.
1091   assert(m->can_be_statically_bound(), "");
1092   m->set_vtable_index(Method::nonvirtual_vtable_index);
1093   m->link_method(m, CHECK_(empty));
1094 
1095   if (TraceMethodHandles && (Verbose || WizardMode))
1096     m->print_on(tty);
1097 
1098   return m;
1099 }
1100 
1101 Klass* Method::check_non_bcp_klass(Klass* klass) {
1102   if (klass != NULL && klass->class_loader() != NULL) {
1103     if (klass->oop_is_objArray())
1104       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1105     return klass;
1106   }
1107   return NULL;
1108 }
1109 
1110 
1111 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1112                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1113   // Code below does not work for native methods - they should never get rewritten anyway
1114   assert(!m->is_native(), "cannot rewrite native methods");
1115   // Allocate new Method*
1116   AccessFlags flags = m->access_flags();
1117 
1118   ConstMethod* cm = m->constMethod();
1119   int checked_exceptions_len = cm->checked_exceptions_length();
1120   int localvariable_len = cm->localvariable_table_length();
1121   int exception_table_len = cm->exception_table_length();
1122   int method_parameters_len = cm->method_parameters_length();
1123   int method_annotations_len = cm->method_annotations_length();
1124   int parameter_annotations_len = cm->parameter_annotations_length();
1125   int type_annotations_len = cm->type_annotations_length();
1126   int default_annotations_len = cm->default_annotations_length();
1127 
1128   InlineTableSizes sizes(
1129       localvariable_len,
1130       new_compressed_linenumber_size,
1131       exception_table_len,
1132       checked_exceptions_len,
1133       method_parameters_len,
1134       cm->generic_signature_index(),
1135       method_annotations_len,
1136       parameter_annotations_len,
1137       type_annotations_len,
1138       default_annotations_len,
1139       0);
1140 
1141   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1142   Method* newm_oop = Method::allocate(loader_data,
1143                                       new_code_length,
1144                                       flags,
1145                                       &sizes,
1146                                       m->method_type(),
1147                                       CHECK_(methodHandle()));
1148   methodHandle newm (THREAD, newm_oop);
1149   int new_method_size = newm->method_size();
1150 
1151   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1152   ConstMethod* newcm = newm->constMethod();
1153   int new_const_method_size = newm->constMethod()->size();
1154 
1155   memcpy(newm(), m(), sizeof(Method));
1156 
1157   // Create shallow copy of ConstMethod.
1158   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1159 
1160   // Reset correct method/const method, method size, and parameter info
1161   newm->set_constMethod(newcm);
1162   newm->constMethod()->set_code_size(new_code_length);
1163   newm->constMethod()->set_constMethod_size(new_const_method_size);
1164   newm->set_method_size(new_method_size);
1165   assert(newm->code_size() == new_code_length, "check");
1166   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1167   assert(newm->exception_table_length() == exception_table_len, "check");
1168   assert(newm->localvariable_table_length() == localvariable_len, "check");
1169   // Copy new byte codes
1170   memcpy(newm->code_base(), new_code, new_code_length);
1171   // Copy line number table
1172   if (new_compressed_linenumber_size > 0) {
1173     memcpy(newm->compressed_linenumber_table(),
1174            new_compressed_linenumber_table,
1175            new_compressed_linenumber_size);
1176   }
1177   // Copy checked_exceptions
1178   if (checked_exceptions_len > 0) {
1179     memcpy(newm->checked_exceptions_start(),
1180            m->checked_exceptions_start(),
1181            checked_exceptions_len * sizeof(CheckedExceptionElement));
1182   }
1183   // Copy exception table
1184   if (exception_table_len > 0) {
1185     memcpy(newm->exception_table_start(),
1186            m->exception_table_start(),
1187            exception_table_len * sizeof(ExceptionTableElement));
1188   }
1189   // Copy local variable number table
1190   if (localvariable_len > 0) {
1191     memcpy(newm->localvariable_table_start(),
1192            m->localvariable_table_start(),
1193            localvariable_len * sizeof(LocalVariableTableElement));
1194   }
1195   // Copy stackmap table
1196   if (m->has_stackmap_table()) {
1197     int code_attribute_length = m->stackmap_data()->length();
1198     Array<u1>* stackmap_data =
1199       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1200     memcpy((void*)stackmap_data->adr_at(0),
1201            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1202     newm->set_stackmap_data(stackmap_data);
1203   }
1204 
1205   // copy annotations over to new method
1206   newcm->copy_annotations_from(cm);
1207   return newm;
1208 }
1209 
1210 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1211   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1212   // because we are not loading from core libraries
1213   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1214   // which does not use the class default class loader so we check for its loader here
1215   InstanceKlass* ik = InstanceKlass::cast(holder);
1216   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1217     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1218   }
1219 
1220   // see if the klass name is well-known:
1221   Symbol* klass_name = ik->name();
1222   return vmSymbols::find_sid(klass_name);
1223 }
1224 
1225 void Method::init_intrinsic_id() {
1226   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1227   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1228   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1229   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1230 
1231   // the klass name is well-known:
1232   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1233   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1234 
1235   // ditto for method and signature:
1236   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1237   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1238       && name_id == vmSymbols::NO_SID)
1239     return;
1240   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1241   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1242       && sig_id == vmSymbols::NO_SID)  return;
1243   jshort flags = access_flags().as_short();
1244 
1245   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1246   if (id != vmIntrinsics::_none) {
1247     set_intrinsic_id(id);
1248     return;
1249   }
1250 
1251   // A few slightly irregular cases:
1252   switch (klass_id) {
1253   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1254     // Second chance: check in regular Math.
1255     switch (name_id) {
1256     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1257     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1258     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1259       // pretend it is the corresponding method in the non-strict class:
1260       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1261       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1262       break;
1263     }
1264     break;
1265 
1266   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1267   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1268     if (!is_native())  break;
1269     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1270     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1271       id = vmIntrinsics::_none;
1272     break;
1273   }
1274 
1275   if (id != vmIntrinsics::_none) {
1276     // Set up its iid.  It is an alias method.
1277     set_intrinsic_id(id);
1278     return;
1279   }
1280 }
1281 
1282 // These two methods are static since a GC may move the Method
1283 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1284   if (THREAD->is_Compiler_thread()) {
1285     // There is nothing useful this routine can do from within the Compile thread.
1286     // Hopefully, the signature contains only well-known classes.
1287     // We could scan for this and return true/false, but the caller won't care.
1288     return false;
1289   }
1290   bool sig_is_loaded = true;
1291   Handle class_loader(THREAD, m->method_holder()->class_loader());
1292   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1293   ResourceMark rm(THREAD);
1294   Symbol*  signature = m->signature();
1295   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1296     if (ss.is_object()) {
1297       Symbol* sym = ss.as_symbol(CHECK_(false));
1298       Symbol*  name  = sym;
1299       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1300                                              protection_domain, THREAD);
1301       // We are loading classes eagerly. If a ClassNotFoundException or
1302       // a LinkageError was generated, be sure to ignore it.
1303       if (HAS_PENDING_EXCEPTION) {
1304         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1305             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1306           CLEAR_PENDING_EXCEPTION;
1307         } else {
1308           return false;
1309         }
1310       }
1311       if( klass == NULL) { sig_is_loaded = false; }
1312     }
1313   }
1314   return sig_is_loaded;
1315 }
1316 
1317 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1318   Handle class_loader(THREAD, m->method_holder()->class_loader());
1319   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1320   ResourceMark rm(THREAD);
1321   Symbol*  signature = m->signature();
1322   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1323     if (ss.type() == T_OBJECT) {
1324       Symbol* name = ss.as_symbol_or_null();
1325       if (name == NULL) return true;
1326       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1327       if (klass == NULL) return true;
1328     }
1329   }
1330   return false;
1331 }
1332 
1333 // Exposed so field engineers can debug VM
1334 void Method::print_short_name(outputStream* st) {
1335   ResourceMark rm;
1336 #ifdef PRODUCT
1337   st->print(" %s::", method_holder()->external_name());
1338 #else
1339   st->print(" %s::", method_holder()->internal_name());
1340 #endif
1341   name()->print_symbol_on(st);
1342   if (WizardMode) signature()->print_symbol_on(st);
1343   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1344     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1345 }
1346 
1347 // Comparer for sorting an object array containing
1348 // Method*s.
1349 static int method_comparator(Method* a, Method* b) {
1350   return a->name()->fast_compare(b->name());
1351 }
1352 
1353 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1354 void Method::sort_methods(Array<Method*>* methods, bool idempotent) {
1355   int length = methods->length();
1356   if (length > 1) {
1357     {
1358       No_Safepoint_Verifier nsv;
1359       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1360     }
1361     // Reset method ordering
1362     for (int i = 0; i < length; i++) {
1363       Method* m = methods->at(i);
1364       m->set_method_idnum(i);
1365     }
1366   }
1367 }
1368 
1369 
1370 //-----------------------------------------------------------------------------------
1371 // Non-product code unless JVM/TI needs it
1372 
1373 #if !defined(PRODUCT) || INCLUDE_JVMTI
1374 class SignatureTypePrinter : public SignatureTypeNames {
1375  private:
1376   outputStream* _st;
1377   bool _use_separator;
1378 
1379   void type_name(const char* name) {
1380     if (_use_separator) _st->print(", ");
1381     _st->print(name);
1382     _use_separator = true;
1383   }
1384 
1385  public:
1386   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1387     _st = st;
1388     _use_separator = false;
1389   }
1390 
1391   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1392   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1393 };
1394 
1395 
1396 void Method::print_name(outputStream* st) {
1397   Thread *thread = Thread::current();
1398   ResourceMark rm(thread);
1399   SignatureTypePrinter sig(signature(), st);
1400   st->print("%s ", is_static() ? "static" : "virtual");
1401   sig.print_returntype();
1402   st->print(" %s.", method_holder()->internal_name());
1403   name()->print_symbol_on(st);
1404   st->print("(");
1405   sig.print_parameters();
1406   st->print(")");
1407 }
1408 #endif // !PRODUCT || INCLUDE_JVMTI
1409 
1410 
1411 //-----------------------------------------------------------------------------------
1412 // Non-product code
1413 
1414 #ifndef PRODUCT
1415 void Method::print_codes_on(outputStream* st) const {
1416   print_codes_on(0, code_size(), st);
1417 }
1418 
1419 void Method::print_codes_on(int from, int to, outputStream* st) const {
1420   Thread *thread = Thread::current();
1421   ResourceMark rm(thread);
1422   methodHandle mh (thread, (Method*)this);
1423   BytecodeStream s(mh);
1424   s.set_interval(from, to);
1425   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1426   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1427 }
1428 #endif // not PRODUCT
1429 
1430 
1431 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1432 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1433 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1434 // as end-of-stream terminator.
1435 
1436 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1437   // bci and line number does not compress into single byte.
1438   // Write out escape character and use regular compression for bci and line number.
1439   write_byte((jubyte)0xFF);
1440   write_signed_int(bci_delta);
1441   write_signed_int(line_delta);
1442 }
1443 
1444 // See comment in method.hpp which explains why this exists.
1445 #if defined(_M_AMD64) && _MSC_VER >= 1400
1446 #pragma optimize("", off)
1447 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1448   write_pair_inline(bci, line);
1449 }
1450 #pragma optimize("", on)
1451 #endif
1452 
1453 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1454   _bci = 0;
1455   _line = 0;
1456 };
1457 
1458 
1459 bool CompressedLineNumberReadStream::read_pair() {
1460   jubyte next = read_byte();
1461   // Check for terminator
1462   if (next == 0) return false;
1463   if (next == 0xFF) {
1464     // Escape character, regular compression used
1465     _bci  += read_signed_int();
1466     _line += read_signed_int();
1467   } else {
1468     // Single byte compression used
1469     _bci  += next >> 3;
1470     _line += next & 0x7;
1471   }
1472   return true;
1473 }
1474 
1475 
1476 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1477   BreakpointInfo* bp = method_holder()->breakpoints();
1478   for (; bp != NULL; bp = bp->next()) {
1479     if (bp->match(this, bci)) {
1480       return bp->orig_bytecode();
1481     }
1482   }
1483   ShouldNotReachHere();
1484   return Bytecodes::_shouldnotreachhere;
1485 }
1486 
1487 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1488   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1489   BreakpointInfo* bp = method_holder()->breakpoints();
1490   for (; bp != NULL; bp = bp->next()) {
1491     if (bp->match(this, bci)) {
1492       bp->set_orig_bytecode(code);
1493       // and continue, in case there is more than one
1494     }
1495   }
1496 }
1497 
1498 void Method::set_breakpoint(int bci) {
1499   InstanceKlass* ik = method_holder();
1500   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1501   bp->set_next(ik->breakpoints());
1502   ik->set_breakpoints(bp);
1503   // do this last:
1504   bp->set(this);
1505 }
1506 
1507 static void clear_matches(Method* m, int bci) {
1508   InstanceKlass* ik = m->method_holder();
1509   BreakpointInfo* prev_bp = NULL;
1510   BreakpointInfo* next_bp;
1511   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1512     next_bp = bp->next();
1513     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1514     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1515       // do this first:
1516       bp->clear(m);
1517       // unhook it
1518       if (prev_bp != NULL)
1519         prev_bp->set_next(next_bp);
1520       else
1521         ik->set_breakpoints(next_bp);
1522       delete bp;
1523       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1524       // at same location. So we have multiple matching (method_index and bci)
1525       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1526       // breakpoint for clear_breakpoint request and keep all other method versions
1527       // BreakpointInfo for future clear_breakpoint request.
1528       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1529       // which is being called when class is unloaded. We delete all the Breakpoint
1530       // information for all versions of method. We may not correctly restore the original
1531       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1532       // so these methods won't be used anymore.
1533       if (bci >= 0) {
1534         break;
1535       }
1536     } else {
1537       // This one is a keeper.
1538       prev_bp = bp;
1539     }
1540   }
1541 }
1542 
1543 void Method::clear_breakpoint(int bci) {
1544   assert(bci >= 0, "");
1545   clear_matches(this, bci);
1546 }
1547 
1548 void Method::clear_all_breakpoints() {
1549   clear_matches(this, -1);
1550 }
1551 
1552 
1553 int Method::invocation_count() {
1554   MethodCounters *mcs = method_counters();
1555   if (TieredCompilation) {
1556     MethodData* const mdo = method_data();
1557     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1558         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1559       return InvocationCounter::count_limit;
1560     } else {
1561       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1562              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1563     }
1564   } else {
1565     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1566   }
1567 }
1568 
1569 int Method::backedge_count() {
1570   MethodCounters *mcs = method_counters();
1571   if (TieredCompilation) {
1572     MethodData* const mdo = method_data();
1573     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1574         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1575       return InvocationCounter::count_limit;
1576     } else {
1577       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1578              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1579     }
1580   } else {
1581     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1582   }
1583 }
1584 
1585 int Method::highest_comp_level() const {
1586   const MethodData* mdo = method_data();
1587   if (mdo != NULL) {
1588     return mdo->highest_comp_level();
1589   } else {
1590     return CompLevel_none;
1591   }
1592 }
1593 
1594 int Method::highest_osr_comp_level() const {
1595   const MethodData* mdo = method_data();
1596   if (mdo != NULL) {
1597     return mdo->highest_osr_comp_level();
1598   } else {
1599     return CompLevel_none;
1600   }
1601 }
1602 
1603 void Method::set_highest_comp_level(int level) {
1604   MethodData* mdo = method_data();
1605   if (mdo != NULL) {
1606     mdo->set_highest_comp_level(level);
1607   }
1608 }
1609 
1610 void Method::set_highest_osr_comp_level(int level) {
1611   MethodData* mdo = method_data();
1612   if (mdo != NULL) {
1613     mdo->set_highest_osr_comp_level(level);
1614   }
1615 }
1616 
1617 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1618   _bci = bci;
1619   _name_index = m->name_index();
1620   _signature_index = m->signature_index();
1621   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1622   if (_orig_bytecode == Bytecodes::_breakpoint)
1623     _orig_bytecode = m->orig_bytecode_at(_bci);
1624   _next = NULL;
1625 }
1626 
1627 void BreakpointInfo::set(Method* method) {
1628 #ifdef ASSERT
1629   {
1630     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1631     if (code == Bytecodes::_breakpoint)
1632       code = method->orig_bytecode_at(_bci);
1633     assert(orig_bytecode() == code, "original bytecode must be the same");
1634   }
1635 #endif
1636   Thread *thread = Thread::current();
1637   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1638   method->incr_number_of_breakpoints(thread);
1639   SystemDictionary::notice_modification();
1640   {
1641     // Deoptimize all dependents on this method
1642     HandleMark hm(thread);
1643     methodHandle mh(thread, method);
1644     Universe::flush_dependents_on_method(mh);
1645   }
1646 }
1647 
1648 void BreakpointInfo::clear(Method* method) {
1649   *method->bcp_from(_bci) = orig_bytecode();
1650   assert(method->number_of_breakpoints() > 0, "must not go negative");
1651   method->decr_number_of_breakpoints(Thread::current());
1652 }
1653 
1654 // jmethodID handling
1655 
1656 // This is a block allocating object, sort of like JNIHandleBlock, only a
1657 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1658 // deleted and so we can do some suboptimal things.
1659 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1660 // never get rid of it.
1661 // It would be nice to be able to parameterize the number of methods for
1662 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1663 // into templates.
1664 
1665 // I feel like this brain dead class should exist somewhere in the STL
1666 
1667 class JNIMethodBlock : public CHeapObj<mtClass> {
1668   enum { number_of_methods = 8 };
1669 
1670   Method*         _methods[number_of_methods];
1671   int             _top;
1672   JNIMethodBlock* _next;
1673  public:
1674   static Method* const _free_method;
1675 
1676   JNIMethodBlock() : _next(NULL), _top(0) {
1677     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1678   }
1679 
1680   Method** add_method(Method* m) {
1681     if (_top < number_of_methods) {
1682       // top points to the next free entry.
1683       int i = _top;
1684       _methods[i] = m;
1685       _top++;
1686       return &_methods[i];
1687     } else if (_top == number_of_methods) {
1688       // if the next free entry ran off the block see if there's a free entry
1689       for (int i = 0; i< number_of_methods; i++) {
1690         if (_methods[i] == _free_method) {
1691           _methods[i] = m;
1692           return &_methods[i];
1693         }
1694       }
1695       // Only check each block once for frees.  They're very unlikely.
1696       // Increment top past the end of the block.
1697       _top++;
1698     }
1699     // need to allocate a next block.
1700     if (_next == NULL) {
1701       _next = new JNIMethodBlock();
1702     }
1703     return _next->add_method(m);
1704   }
1705 
1706   bool contains(Method** m) {
1707     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1708       for (int i = 0; i< number_of_methods; i++) {
1709         if (&(b->_methods[i]) == m) {
1710           return true;
1711         }
1712       }
1713     }
1714     return false;  // not found
1715   }
1716 
1717   // Doesn't really destroy it, just marks it as free so it can be reused.
1718   void destroy_method(Method** m) {
1719 #ifdef ASSERT
1720     assert(contains(m), "should be a methodID");
1721 #endif // ASSERT
1722     *m = _free_method;
1723   }
1724 
1725   // During class unloading the methods are cleared, which is different
1726   // than freed.
1727   void clear_all_methods() {
1728     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1729       for (int i = 0; i< number_of_methods; i++) {
1730         _methods[i] = NULL;
1731       }
1732     }
1733   }
1734 #ifndef PRODUCT
1735   int count_methods() {
1736     // count all allocated methods
1737     int count = 0;
1738     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1739       for (int i = 0; i< number_of_methods; i++) {
1740         if (_methods[i] != _free_method) count++;
1741       }
1742     }
1743     return count;
1744   }
1745 #endif // PRODUCT
1746 };
1747 
1748 // Something that can't be mistaken for an address or a markOop
1749 Method* const JNIMethodBlock::_free_method = (Method*)55;
1750 
1751 // Add a method id to the jmethod_ids
1752 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1753   ClassLoaderData* cld = loader_data;
1754 
1755   if (!SafepointSynchronize::is_at_safepoint()) {
1756     // Have to add jmethod_ids() to class loader data thread-safely.
1757     // Also have to add the method to the list safely, which the cld lock
1758     // protects as well.
1759     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1760     if (cld->jmethod_ids() == NULL) {
1761       cld->set_jmethod_ids(new JNIMethodBlock());
1762     }
1763     // jmethodID is a pointer to Method*
1764     return (jmethodID)cld->jmethod_ids()->add_method(m);
1765   } else {
1766     // At safepoint, we are single threaded and can set this.
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   }
1773 }
1774 
1775 // Mark a jmethodID as free.  This is called when there is a data race in
1776 // InstanceKlass while creating the jmethodID cache.
1777 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1778   ClassLoaderData* cld = loader_data;
1779   Method** ptr = (Method**)m;
1780   assert(cld->jmethod_ids() != NULL, "should have method handles");
1781   cld->jmethod_ids()->destroy_method(ptr);
1782 }
1783 
1784 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1785   // Can't assert the method_holder is the same because the new method has the
1786   // scratch method holder.
1787   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1788            == new_method->method_holder()->class_loader(),
1789          "changing to a different class loader");
1790   // Just change the method in place, jmethodID pointer doesn't change.
1791   *((Method**)jmid) = new_method;
1792 }
1793 
1794 bool Method::is_method_id(jmethodID mid) {
1795   Method* m = resolve_jmethod_id(mid);
1796   assert(m != NULL, "should be called with non-null method");
1797   InstanceKlass* ik = m->method_holder();
1798   ClassLoaderData* cld = ik->class_loader_data();
1799   if (cld->jmethod_ids() == NULL) return false;
1800   return (cld->jmethod_ids()->contains((Method**)mid));
1801 }
1802 
1803 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1804   if (mid == NULL) return NULL;
1805   Method* o = resolve_jmethod_id(mid);
1806   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1807     return NULL;
1808   }
1809   return o;
1810 };
1811 
1812 void Method::set_on_stack(const bool value) {
1813   // Set both the method itself and its constant pool.  The constant pool
1814   // on stack means some method referring to it is also on the stack.
1815   _access_flags.set_on_stack(value);
1816   constants()->set_on_stack(value);
1817   if (value) MetadataOnStackMark::record(this);
1818 }
1819 
1820 // Called when the class loader is unloaded to make all methods weak.
1821 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1822   loader_data->jmethod_ids()->clear_all_methods();
1823 }
1824 
1825 
1826 // Check that this pointer is valid by checking that the vtbl pointer matches
1827 bool Method::is_valid_method() const {
1828   if (this == NULL) {
1829     return false;
1830   } else if (!is_metaspace_object()) {
1831     return false;
1832   } else {
1833     Method m;
1834     // This assumes that the vtbl pointer is the first word of a C++ object.
1835     // This assumption is also in universe.cpp patch_klass_vtble
1836     void* vtbl2 = dereference_vptr((void*)&m);
1837     void* this_vtbl = dereference_vptr((void*)this);
1838     return vtbl2 == this_vtbl;
1839   }
1840 }
1841 
1842 #ifndef PRODUCT
1843 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1844   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1845 }
1846 #endif // PRODUCT
1847 
1848 
1849 // Printing
1850 
1851 #ifndef PRODUCT
1852 
1853 void Method::print_on(outputStream* st) const {
1854   ResourceMark rm;
1855   assert(is_method(), "must be method");
1856   st->print_cr(internal_name());
1857   // get the effect of PrintOopAddress, always, for methods:
1858   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1859   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1860   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1861   constants()->print_value_on(st); st->cr();
1862   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1863   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1864   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1865   st->print_cr(" - max stack:         %d",   max_stack());
1866   st->print_cr(" - max locals:        %d",   max_locals());
1867   st->print_cr(" - size of params:    %d",   size_of_parameters());
1868   st->print_cr(" - method size:       %d",   method_size());
1869   if (intrinsic_id() != vmIntrinsics::_none)
1870     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1871   if (highest_comp_level() != CompLevel_none)
1872     st->print_cr(" - highest level:     %d", highest_comp_level());
1873   st->print_cr(" - vtable index:      %d",   _vtable_index);
1874   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1875   st->print(   " - adapters:          ");
1876   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1877   if (a == NULL)
1878     st->print_cr(INTPTR_FORMAT, a);
1879   else
1880     a->print_adapter_on(st);
1881   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1882   st->print_cr(" - code size:         %d",   code_size());
1883   if (code_size() != 0) {
1884     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1885     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1886   }
1887   if (method_data() != NULL) {
1888     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1889   }
1890   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1891   if (checked_exceptions_length() > 0) {
1892     CheckedExceptionElement* table = checked_exceptions_start();
1893     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1894     if (Verbose) {
1895       for (int i = 0; i < checked_exceptions_length(); i++) {
1896         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1897       }
1898     }
1899   }
1900   if (has_linenumber_table()) {
1901     u_char* table = compressed_linenumber_table();
1902     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1903     if (Verbose) {
1904       CompressedLineNumberReadStream stream(table);
1905       while (stream.read_pair()) {
1906         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1907       }
1908     }
1909   }
1910   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1911   if (localvariable_table_length() > 0) {
1912     LocalVariableTableElement* table = localvariable_table_start();
1913     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1914     if (Verbose) {
1915       for (int i = 0; i < localvariable_table_length(); i++) {
1916         int bci = table[i].start_bci;
1917         int len = table[i].length;
1918         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1919         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
1920         int slot = table[i].slot;
1921         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
1922       }
1923     }
1924   }
1925   if (code() != NULL) {
1926     st->print   (" - compiled code: ");
1927     code()->print_value_on(st);
1928   }
1929   if (is_native()) {
1930     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
1931     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
1932   }
1933 }
1934 
1935 #endif //PRODUCT
1936 
1937 void Method::print_value_on(outputStream* st) const {
1938   assert(is_method(), "must be method");
1939   st->print_cr(internal_name());
1940   print_address_on(st);
1941   st->print(" ");
1942   name()->print_value_on(st);
1943   st->print(" ");
1944   signature()->print_value_on(st);
1945   st->print(" in ");
1946   method_holder()->print_value_on(st);
1947   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
1948   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
1949 }
1950 
1951 #if INCLUDE_SERVICES
1952 // Size Statistics
1953 void Method::collect_statistics(KlassSizeStats *sz) const {
1954   int mysize = sz->count(this);
1955   sz->_method_bytes += mysize;
1956   sz->_method_all_bytes += mysize;
1957   sz->_rw_bytes += mysize;
1958 
1959   if (constMethod()) {
1960     constMethod()->collect_statistics(sz);
1961   }
1962   if (method_data()) {
1963     method_data()->collect_statistics(sz);
1964   }
1965 }
1966 #endif // INCLUDE_SERVICES
1967 
1968 // Verification
1969 
1970 void Method::verify_on(outputStream* st) {
1971   guarantee(is_method(), "object must be method");
1972   guarantee(constants()->is_constantPool(), "should be constant pool");
1973   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
1974   MethodData* md = method_data();
1975   guarantee(md == NULL ||
1976       md->is_methodData(), "should be method data");
1977 }