1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/debugInfoRec.hpp"
  29 #include "gc_interface/collectedHeap.inline.hpp"
  30 #include "interpreter/bytecodeStream.hpp"
  31 #include "interpreter/bytecodeTracer.hpp"
  32 #include "interpreter/bytecodes.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "memory/gcLocker.hpp"
  36 #include "memory/generation.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/oopFactory.hpp"
  40 #include "oops/constMethod.hpp"
  41 #include "oops/methodData.hpp"
  42 #include "oops/method.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "oops/symbol.hpp"
  45 #include "prims/jvmtiExport.hpp"
  46 #include "prims/methodHandles.hpp"
  47 #include "prims/nativeLookup.hpp"
  48 #include "runtime/arguments.hpp"
  49 #include "runtime/compilationPolicy.hpp"
  50 #include "runtime/frame.inline.hpp"
  51 #include "runtime/handles.inline.hpp"
  52 #include "runtime/orderAccess.inline.hpp"
  53 #include "runtime/relocator.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "utilities/quickSort.hpp"
  57 #include "utilities/xmlstream.hpp"
  58 
  59 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  60 
  61 // Implementation of Method
  62 
  63 Method* Method::allocate(ClassLoaderData* loader_data,
  64                          int byte_code_size,
  65                          AccessFlags access_flags,
  66                          InlineTableSizes* sizes,
  67                          ConstMethod::MethodType method_type,
  68                          TRAPS) {
  69   assert(!access_flags.is_native() || byte_code_size == 0,
  70          "native methods should not contain byte codes");
  71   ConstMethod* cm = ConstMethod::allocate(loader_data,
  72                                           byte_code_size,
  73                                           sizes,
  74                                           method_type,
  75                                           CHECK_NULL);
  76 
  77   int size = Method::size(access_flags.is_native());
  78 
  79   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  80 }
  81 
  82 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  83   No_Safepoint_Verifier no_safepoint;
  84   set_constMethod(xconst);
  85   set_access_flags(access_flags);
  86   set_method_size(size);
  87 #ifdef CC_INTERP
  88   set_result_index(T_VOID);
  89 #endif
  90   set_intrinsic_id(vmIntrinsics::_none);
  91   set_jfr_towrite(false);
  92   set_force_inline(false);
  93   set_hidden(false);
  94   set_dont_inline(false);
  95   set_method_data(NULL);
  96   set_method_counters(NULL);
  97   set_vtable_index(Method::garbage_vtable_index);
  98 
  99   // Fix and bury in Method*
 100   set_interpreter_entry(NULL); // sets i2i entry and from_int
 101   set_adapter_entry(NULL);
 102   clear_code(); // from_c/from_i get set to c2i/i2i
 103 
 104   if (access_flags.is_native()) {
 105     clear_native_function();
 106     set_signature_handler(NULL);
 107   }
 108 
 109   NOT_PRODUCT(set_compiled_invocation_count(0);)
 110 }
 111 
 112 // Release Method*.  The nmethod will be gone when we get here because
 113 // we've walked the code cache.
 114 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 115   MetadataFactory::free_metadata(loader_data, constMethod());
 116   set_constMethod(NULL);
 117   MetadataFactory::free_metadata(loader_data, method_data());
 118   set_method_data(NULL);
 119   MetadataFactory::free_metadata(loader_data, method_counters());
 120   set_method_counters(NULL);
 121   // The nmethod will be gone when we get here.
 122   if (code() != NULL) _code = NULL;
 123 }
 124 
 125 address Method::get_i2c_entry() {
 126   assert(_adapter != NULL, "must have");
 127   return _adapter->get_i2c_entry();
 128 }
 129 
 130 address Method::get_c2i_entry() {
 131   assert(_adapter != NULL, "must have");
 132   return _adapter->get_c2i_entry();
 133 }
 134 
 135 address Method::get_c2i_unverified_entry() {
 136   assert(_adapter != NULL, "must have");
 137   return _adapter->get_c2i_unverified_entry();
 138 }
 139 
 140 char* Method::name_and_sig_as_C_string() const {
 141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 142 }
 143 
 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 146 }
 147 
 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 149   const char* klass_name = klass->external_name();
 150   int klass_name_len  = (int)strlen(klass_name);
 151   int method_name_len = method_name->utf8_length();
 152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 154   strcpy(dest, klass_name);
 155   dest[klass_name_len] = '.';
 156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 158   dest[len] = 0;
 159   return dest;
 160 }
 161 
 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 163   Symbol* klass_name = klass->name();
 164   klass_name->as_klass_external_name(buf, size);
 165   int len = (int)strlen(buf);
 166 
 167   if (len < size - 1) {
 168     buf[len++] = '.';
 169 
 170     method_name->as_C_string(&(buf[len]), size - len);
 171     len = (int)strlen(buf);
 172 
 173     signature->as_C_string(&(buf[len]), size - len);
 174   }
 175 
 176   return buf;
 177 }
 178 
 179 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 181   // access exception table
 182   ExceptionTable table(mh());
 183   int length = table.length();
 184   // iterate through all entries sequentially
 185   constantPoolHandle pool(THREAD, mh->constants());
 186   for (int i = 0; i < length; i ++) {
 187     //reacquire the table in case a GC happened
 188     ExceptionTable table(mh());
 189     int beg_bci = table.start_pc(i);
 190     int end_bci = table.end_pc(i);
 191     assert(beg_bci <= end_bci, "inconsistent exception table");
 192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 193       // exception handler bci range covers throw_bci => investigate further
 194       int handler_bci = table.handler_pc(i);
 195       int klass_index = table.catch_type_index(i);
 196       if (klass_index == 0) {
 197         return handler_bci;
 198       } else if (ex_klass.is_null()) {
 199         return handler_bci;
 200       } else {
 201         // we know the exception class => get the constraint class
 202         // this may require loading of the constraint class; if verification
 203         // fails or some other exception occurs, return handler_bci
 204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 205         KlassHandle klass = KlassHandle(THREAD, k);
 206         assert(klass.not_null(), "klass not loaded");
 207         if (ex_klass->is_subtype_of(klass())) {
 208           return handler_bci;
 209         }
 210       }
 211     }
 212   }
 213 
 214   return -1;
 215 }
 216 
 217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 218 
 219   Thread* myThread    = Thread::current();
 220   methodHandle h_this(myThread, this);
 221 #ifdef ASSERT
 222   bool has_capability = myThread->is_VM_thread() ||
 223                         myThread->is_ConcurrentGC_thread() ||
 224                         myThread->is_GC_task_thread();
 225 
 226   if (!has_capability) {
 227     if (!VerifyStack && !VerifyLastFrame) {
 228       // verify stack calls this outside VM thread
 229       warning("oopmap should only be accessed by the "
 230               "VM, GC task or CMS threads (or during debugging)");
 231       InterpreterOopMap local_mask;
 232       method_holder()->mask_for(h_this, bci, &local_mask);
 233       local_mask.print();
 234     }
 235   }
 236 #endif
 237   method_holder()->mask_for(h_this, bci, mask);
 238   return;
 239 }
 240 
 241 
 242 int Method::bci_from(address bcp) const {
 243   if (is_native() && bcp == 0) {
 244     return 0;
 245   }
 246 #ifdef ASSERT
 247   { ResourceMark rm;
 248   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 249          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 250   }
 251 #endif
 252   return bcp - code_base();
 253 }
 254 
 255 
 256 int Method::validate_bci(int bci) const {
 257   return (bci == 0 || bci < code_size()) ? bci : -1;
 258 }
 259 
 260 // Return bci if it appears to be a valid bcp
 261 // Return -1 otherwise.
 262 // Used by profiling code, when invalid data is a possibility.
 263 // The caller is responsible for validating the Method* itself.
 264 int Method::validate_bci_from_bcp(address bcp) const {
 265   // keep bci as -1 if not a valid bci
 266   int bci = -1;
 267   if (bcp == 0 || bcp == code_base()) {
 268     // code_size() may return 0 and we allow 0 here
 269     // the method may be native
 270     bci = 0;
 271   } else if (contains(bcp)) {
 272     bci = bcp - code_base();
 273   }
 274   // Assert that if we have dodged any asserts, bci is negative.
 275   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 276   return bci;
 277 }
 278 
 279 address Method::bcp_from(int bci) const {
 280   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), err_msg("illegal bci: %d", bci));
 281   address bcp = code_base() + bci;
 282   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 283   return bcp;
 284 }
 285 
 286 address Method::bcp_from(address bcp) const {
 287   if (is_native() && bcp == NULL) {
 288     return code_base();
 289   } else {
 290     return bcp;
 291   }
 292 }
 293 
 294 int Method::size(bool is_native) {
 295   // If native, then include pointers for native_function and signature_handler
 296   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 297   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 298   return align_object_size(header_size() + extra_words);
 299 }
 300 
 301 
 302 Symbol* Method::klass_name() const {
 303   Klass* k = method_holder();
 304   assert(k->is_klass(), "must be klass");
 305   InstanceKlass* ik = (InstanceKlass*) k;
 306   return ik->name();
 307 }
 308 
 309 
 310 // Attempt to return method oop to original state.  Clear any pointers
 311 // (to objects outside the shared spaces).  We won't be able to predict
 312 // where they should point in a new JVM.  Further initialize some
 313 // entries now in order allow them to be write protected later.
 314 
 315 void Method::remove_unshareable_info() {
 316   unlink_method();
 317 }
 318 
 319 
 320 bool Method::was_executed_more_than(int n) {
 321   // Invocation counter is reset when the Method* is compiled.
 322   // If the method has compiled code we therefore assume it has
 323   // be excuted more than n times.
 324   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 325     // interpreter doesn't bump invocation counter of trivial methods
 326     // compiler does not bump invocation counter of compiled methods
 327     return true;
 328   }
 329   else if ((method_counters() != NULL &&
 330             method_counters()->invocation_counter()->carry()) ||
 331            (method_data() != NULL &&
 332             method_data()->invocation_counter()->carry())) {
 333     // The carry bit is set when the counter overflows and causes
 334     // a compilation to occur.  We don't know how many times
 335     // the counter has been reset, so we simply assume it has
 336     // been executed more than n times.
 337     return true;
 338   } else {
 339     return invocation_count() > n;
 340   }
 341 }
 342 
 343 void Method::print_invocation_count() {
 344   if (is_static()) tty->print("static ");
 345   if (is_final()) tty->print("final ");
 346   if (is_synchronized()) tty->print("synchronized ");
 347   if (is_native()) tty->print("native ");
 348   tty->print("%s::", method_holder()->external_name());
 349   name()->print_symbol_on(tty);
 350   signature()->print_symbol_on(tty);
 351 
 352   if (WizardMode) {
 353     // dump the size of the byte codes
 354     tty->print(" {%d}", code_size());
 355   }
 356   tty->cr();
 357 
 358   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 359   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 360   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 361 #ifndef PRODUCT
 362   if (CountCompiledCalls) {
 363     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 364   }
 365 #endif
 366 }
 367 
 368 // Build a MethodData* object to hold information about this method
 369 // collected in the interpreter.
 370 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 371   // Do not profile method if current thread holds the pending list lock,
 372   // which avoids deadlock for acquiring the MethodData_lock.
 373   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 374     return;
 375   }
 376 
 377   // Grab a lock here to prevent multiple
 378   // MethodData*s from being created.
 379   MutexLocker ml(MethodData_lock, THREAD);
 380   if (method->method_data() == NULL) {
 381     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 382     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 383     method->set_method_data(method_data);
 384     if (PrintMethodData && (Verbose || WizardMode)) {
 385       ResourceMark rm(THREAD);
 386       tty->print("build_interpreter_method_data for ");
 387       method->print_name(tty);
 388       tty->cr();
 389       // At the end of the run, the MDO, full of data, will be dumped.
 390     }
 391   }
 392 }
 393 
 394 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 395   methodHandle mh(m);
 396   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
 397   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
 398   if (!mh->init_method_counters(counters)) {


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