1 /*
   2  * Copyright (c) 1997, 2016, 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/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "gc/shared/collectedHeap.inline.hpp"
  31 #include "gc/shared/gcLocker.hpp"
  32 #include "gc/shared/generation.hpp"
  33 #include "interpreter/bytecodeStream.hpp"
  34 #include "interpreter/bytecodeTracer.hpp"
  35 #include "interpreter/bytecodes.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/oopMapCache.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceShared.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "oops/constMethod.hpp"
  44 #include "oops/method.hpp"
  45 #include "oops/methodData.hpp"
  46 #include "oops/objArrayOop.inline.hpp"
  47 #include "oops/oop.inline.hpp"
  48 #include "oops/symbol.hpp"
  49 #include "prims/jvmtiExport.hpp"
  50 #include "prims/methodHandles.hpp"
  51 #include "prims/nativeLookup.hpp"
  52 #include "runtime/arguments.hpp"
  53 #include "runtime/compilationPolicy.hpp"
  54 #include "runtime/frame.inline.hpp"
  55 #include "runtime/handles.inline.hpp"
  56 #include "runtime/init.hpp"
  57 #include "runtime/orderAccess.inline.hpp"
  58 #include "runtime/relocator.hpp"
  59 #include "runtime/sharedRuntime.hpp"
  60 #include "runtime/signature.hpp"
  61 #include "utilities/quickSort.hpp"
  62 #include "utilities/xmlstream.hpp"
  63 
  64 // Implementation of Method
  65 
  66 Method* Method::allocate(ClassLoaderData* loader_data,
  67                          int byte_code_size,
  68                          AccessFlags access_flags,
  69                          InlineTableSizes* sizes,
  70                          ConstMethod::MethodType method_type,
  71                          TRAPS) {
  72   assert(!access_flags.is_native() || byte_code_size == 0,
  73          "native methods should not contain byte codes");
  74   ConstMethod* cm = ConstMethod::allocate(loader_data,
  75                                           byte_code_size,
  76                                           sizes,
  77                                           method_type,
  78                                           CHECK_NULL);
  79   int size = Method::size(access_flags.is_native());
  80   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  81 }
  82 
  83 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  84   NoSafepointVerifier no_safepoint;
  85   set_constMethod(xconst);
  86   set_access_flags(access_flags);
  87   set_intrinsic_id(vmIntrinsics::_none);
  88   set_jfr_towrite(false);
  89   set_force_inline(false);
  90   set_hidden(false);
  91   set_dont_inline(false);
  92   set_has_injected_profile(false);
  93   set_method_data(NULL);
  94   clear_method_counters();
  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   clear_method_counters();
 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 #if defined(ASSERT) && !INCLUDE_JVMCI
 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   if (is_native() && bcp == 0) {
 242     return 0;
 243   }
 244 #ifdef ASSERT
 245   {
 246     ResourceMark rm;
 247     assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 248            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 249            p2i(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()),
 281          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 282   address bcp = code_base() + bci;
 283   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 284   return bcp;
 285 }
 286 
 287 address Method::bcp_from(address bcp) const {
 288   if (is_native() && bcp == NULL) {
 289     return code_base();
 290   } else {
 291     return bcp;
 292   }
 293 }
 294 
 295 int Method::size(bool is_native) {
 296   // If native, then include pointers for native_function and signature_handler
 297   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 298   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 299   return align_metadata_size(header_size() + extra_words);
 300 }
 301 
 302 
 303 Symbol* Method::klass_name() const {
 304   return method_holder()->name();
 305 }
 306 
 307 
 308 // Attempt to return method oop to original state.  Clear any pointers
 309 // (to objects outside the shared spaces).  We won't be able to predict
 310 // where they should point in a new JVM.  Further initialize some
 311 // entries now in order allow them to be write protected later.
 312 
 313 void Method::remove_unshareable_info() {
 314   unlink_method();
 315 }
 316 
 317 void Method::set_vtable_index(int index) {
 318   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 319     // At runtime initialize_vtable is rerun as part of link_class_impl()
 320     // for a shared class loaded by the non-boot loader to obtain the loader
 321     // constraints based on the runtime classloaders' context.
 322     return; // don't write into the shared class
 323   } else {
 324     _vtable_index = index;
 325   }
 326 }
 327 
 328 void Method::set_itable_index(int index) {
 329   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 330     // At runtime initialize_itable is rerun as part of link_class_impl()
 331     // for a shared class loaded by the non-boot loader to obtain the loader
 332     // constraints based on the runtime classloaders' context. The dumptime
 333     // itable index should be the same as the runtime index.
 334     assert(_vtable_index == itable_index_max - index,
 335            "archived itable index is different from runtime index");
 336     return; // don’t write into the shared class
 337   } else {
 338     _vtable_index = itable_index_max - index;
 339   }
 340   assert(valid_itable_index(), "");
 341 }
 342 
 343 
 344 
 345 bool Method::was_executed_more_than(int n) {
 346   // Invocation counter is reset when the Method* is compiled.
 347   // If the method has compiled code we therefore assume it has
 348   // be excuted more than n times.
 349   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 350     // interpreter doesn't bump invocation counter of trivial methods
 351     // compiler does not bump invocation counter of compiled methods
 352     return true;
 353   }
 354   else if ((method_counters() != NULL &&
 355             method_counters()->invocation_counter()->carry()) ||
 356            (method_data() != NULL &&
 357             method_data()->invocation_counter()->carry())) {
 358     // The carry bit is set when the counter overflows and causes
 359     // a compilation to occur.  We don't know how many times
 360     // the counter has been reset, so we simply assume it has
 361     // been executed more than n times.
 362     return true;
 363   } else {
 364     return invocation_count() > n;
 365   }
 366 }
 367 
 368 void Method::print_invocation_count() {
 369   if (is_static()) tty->print("static ");
 370   if (is_final()) tty->print("final ");
 371   if (is_synchronized()) tty->print("synchronized ");
 372   if (is_native()) tty->print("native ");
 373   tty->print("%s::", method_holder()->external_name());
 374   name()->print_symbol_on(tty);
 375   signature()->print_symbol_on(tty);
 376 
 377   if (WizardMode) {
 378     // dump the size of the byte codes
 379     tty->print(" {%d}", code_size());
 380   }
 381   tty->cr();
 382 
 383   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 384   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 385   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 386 #ifndef PRODUCT
 387   if (CountCompiledCalls) {
 388     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 389   }
 390 #endif
 391 }
 392 
 393 // Build a MethodData* object to hold information about this method
 394 // collected in the interpreter.
 395 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 396   // Do not profile the method if metaspace has hit an OOM previously
 397   // allocating profiling data. Callers clear pending exception so don't
 398   // add one here.
 399   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 400     return;
 401   }
 402 
 403   // Grab a lock here to prevent multiple
 404   // MethodData*s from being created.
 405   MutexLocker ml(MethodData_lock, THREAD);
 406   if (method->method_data() == NULL) {
 407     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 408     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 409     if (HAS_PENDING_EXCEPTION) {
 410       CompileBroker::log_metaspace_failure();
 411       ClassLoaderDataGraph::set_metaspace_oom(true);
 412       return;   // return the exception (which is cleared)
 413     }
 414 
 415     method->set_method_data(method_data);
 416     if (PrintMethodData && (Verbose || WizardMode)) {
 417       ResourceMark rm(THREAD);
 418       tty->print("build_interpreter_method_data for ");
 419       method->print_name(tty);
 420       tty->cr();
 421       // At the end of the run, the MDO, full of data, will be dumped.
 422     }
 423   }
 424 }
 425 
 426 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 427   // Do not profile the method if metaspace has hit an OOM previously
 428   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 429     return NULL;
 430   }
 431 
 432   methodHandle mh(m);
 433   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 434   if (HAS_PENDING_EXCEPTION) {
 435     CompileBroker::log_metaspace_failure();
 436     ClassLoaderDataGraph::set_metaspace_oom(true);
 437     return NULL;   // return the exception (which is cleared)
 438   }
 439   if (!mh->init_method_counters(counters)) {
 440     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 441   }
 442 
 443   if (LogTouchedMethods) {
 444     mh->log_touched(CHECK_NULL);
 445   }
 446 
 447   return mh->method_counters();
 448 }
 449 
 450 void Method::cleanup_inline_caches() {
 451   // The current system doesn't use inline caches in the interpreter
 452   // => nothing to do (keep this method around for future use)
 453 }
 454 
 455 
 456 int Method::extra_stack_words() {
 457   // not an inline function, to avoid a header dependency on Interpreter
 458   return extra_stack_entries() * Interpreter::stackElementSize;
 459 }
 460 
 461 
 462 void Method::compute_size_of_parameters(Thread *thread) {
 463   ArgumentSizeComputer asc(signature());
 464   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 465 }
 466 
 467 BasicType Method::result_type() const {
 468   ResultTypeFinder rtf(signature());
 469   return rtf.type();
 470 }
 471 
 472 
 473 bool Method::is_empty_method() const {
 474   return  code_size() == 1
 475       && *code_base() == Bytecodes::_return;
 476 }
 477 
 478 
 479 bool Method::is_vanilla_constructor() const {
 480   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 481   // which only calls the superclass vanilla constructor and possibly does stores of
 482   // zero constants to local fields:
 483   //
 484   //   aload_0
 485   //   invokespecial
 486   //   indexbyte1
 487   //   indexbyte2
 488   //
 489   // followed by an (optional) sequence of:
 490   //
 491   //   aload_0
 492   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 493   //   putfield
 494   //   indexbyte1
 495   //   indexbyte2
 496   //
 497   // followed by:
 498   //
 499   //   return
 500 
 501   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 502   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 503   int size = code_size();
 504   // Check if size match
 505   if (size == 0 || size % 5 != 0) return false;
 506   address cb = code_base();
 507   int last = size - 1;
 508   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 509     // Does not call superclass default constructor
 510     return false;
 511   }
 512   // Check optional sequence
 513   for (int i = 4; i < last; i += 5) {
 514     if (cb[i] != Bytecodes::_aload_0) return false;
 515     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 516     if (cb[i+2] != Bytecodes::_putfield) return false;
 517   }
 518   return true;
 519 }
 520 
 521 
 522 bool Method::compute_has_loops_flag() {
 523   BytecodeStream bcs(this);
 524   Bytecodes::Code bc;
 525 
 526   while ((bc = bcs.next()) >= 0) {
 527     switch( bc ) {
 528       case Bytecodes::_ifeq:
 529       case Bytecodes::_ifnull:
 530       case Bytecodes::_iflt:
 531       case Bytecodes::_ifle:
 532       case Bytecodes::_ifne:
 533       case Bytecodes::_ifnonnull:
 534       case Bytecodes::_ifgt:
 535       case Bytecodes::_ifge:
 536       case Bytecodes::_if_icmpeq:
 537       case Bytecodes::_if_icmpne:
 538       case Bytecodes::_if_icmplt:
 539       case Bytecodes::_if_icmpgt:
 540       case Bytecodes::_if_icmple:
 541       case Bytecodes::_if_icmpge:
 542       case Bytecodes::_if_acmpeq:
 543       case Bytecodes::_if_acmpne:
 544       case Bytecodes::_goto:
 545       case Bytecodes::_jsr:
 546         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 547         break;
 548 
 549       case Bytecodes::_goto_w:
 550       case Bytecodes::_jsr_w:
 551         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 552         break;
 553     }
 554   }
 555   _access_flags.set_loops_flag_init();
 556   return _access_flags.has_loops();
 557 }
 558 
 559 bool Method::is_final_method(AccessFlags class_access_flags) const {
 560   // or "does_not_require_vtable_entry"
 561   // default method or overpass can occur, is not final (reuses vtable entry)
 562   // private methods in classes get vtable entries for backward class compatibility.
 563   if (is_overpass() || is_default_method())  return false;
 564   return is_final() || class_access_flags.is_final();
 565 }
 566 
 567 bool Method::is_final_method() const {
 568   return is_final_method(method_holder()->access_flags());
 569 }
 570 
 571 bool Method::is_default_method() const {
 572   if (method_holder() != NULL &&
 573       method_holder()->is_interface() &&
 574       !is_abstract() && !is_private()) {
 575     return true;
 576   } else {
 577     return false;
 578   }
 579 }
 580 
 581 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 582   if (is_final_method(class_access_flags))  return true;
 583 #ifdef ASSERT
 584   ResourceMark rm;
 585   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 586   if (class_access_flags.is_interface()) {
 587       assert(is_nonv == is_static() || is_nonv == is_private(),
 588              "nonvirtual unexpected for non-static, non-private: %s",
 589              name_and_sig_as_C_string());
 590   }
 591 #endif
 592   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 593   return vtable_index() == nonvirtual_vtable_index;
 594 }
 595 
 596 bool Method::can_be_statically_bound() const {
 597   return can_be_statically_bound(method_holder()->access_flags());
 598 }
 599 
 600 bool Method::is_accessor() const {
 601   return is_getter() || is_setter();
 602 }
 603 
 604 bool Method::is_getter() const {
 605   if (code_size() != 5) return false;
 606   if (size_of_parameters() != 1) return false;
 607   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 608   if (java_code_at(1) != Bytecodes::_getfield) return false;
 609   switch (java_code_at(4)) {
 610     case Bytecodes::_ireturn:
 611     case Bytecodes::_lreturn:
 612     case Bytecodes::_freturn:
 613     case Bytecodes::_dreturn:
 614     case Bytecodes::_areturn:
 615       break;
 616     default:
 617       return false;
 618   }
 619   return true;
 620 }
 621 
 622 bool Method::is_setter() const {
 623   if (code_size() != 6) return false;
 624   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 625   switch (java_code_at(1)) {
 626     case Bytecodes::_iload_1:
 627     case Bytecodes::_aload_1:
 628     case Bytecodes::_fload_1:
 629       if (size_of_parameters() != 2) return false;
 630       break;
 631     case Bytecodes::_dload_1:
 632     case Bytecodes::_lload_1:
 633       if (size_of_parameters() != 3) return false;
 634       break;
 635     default:
 636       return false;
 637   }
 638   if (java_code_at(2) != Bytecodes::_putfield) return false;
 639   if (java_code_at(5) != Bytecodes::_return)   return false;
 640   return true;
 641 }
 642 
 643 bool Method::is_constant_getter() const {
 644   int last_index = code_size() - 1;
 645   // Check if the first 1-3 bytecodes are a constant push
 646   // and the last bytecode is a return.
 647   return (2 <= code_size() && code_size() <= 4 &&
 648           Bytecodes::is_const(java_code_at(0)) &&
 649           Bytecodes::length_for(java_code_at(0)) == last_index &&
 650           Bytecodes::is_return(java_code_at(last_index)));
 651 }
 652 
 653 bool Method::is_initializer() const {
 654   return is_object_initializer() || is_static_initializer();
 655 }
 656 
 657 bool Method::has_valid_initializer_flags() const {
 658   return (is_static() ||
 659           method_holder()->major_version() < 51);
 660 }
 661 
 662 bool Method::is_static_initializer() const {
 663   // For classfiles version 51 or greater, ensure that the clinit method is
 664   // static.  Non-static methods with the name "<clinit>" are not static
 665   // initializers. (older classfiles exempted for backward compatibility)
 666   return name() == vmSymbols::class_initializer_name() &&
 667          has_valid_initializer_flags();
 668 }
 669 
 670 bool Method::is_object_initializer() const {
 671    return name() == vmSymbols::object_initializer_name();
 672 }
 673 
 674 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 675   int length = method->checked_exceptions_length();
 676   if (length == 0) {  // common case
 677     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 678   } else {
 679     methodHandle h_this(THREAD, method);
 680     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 681     objArrayHandle mirrors (THREAD, m_oop);
 682     for (int i = 0; i < length; i++) {
 683       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 684       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 685       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 686       mirrors->obj_at_put(i, k->java_mirror());
 687     }
 688     return mirrors;
 689   }
 690 };
 691 
 692 
 693 int Method::line_number_from_bci(int bci) const {
 694   if (bci == SynchronizationEntryBCI) bci = 0;
 695   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 696   int best_bci  =  0;
 697   int best_line = -1;
 698 
 699   if (has_linenumber_table()) {
 700     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 701     // Not necessarily sorted and not necessarily one-to-one.
 702     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 703     while (stream.read_pair()) {
 704       if (stream.bci() == bci) {
 705         // perfect match
 706         return stream.line();
 707       } else {
 708         // update best_bci/line
 709         if (stream.bci() < bci && stream.bci() >= best_bci) {
 710           best_bci  = stream.bci();
 711           best_line = stream.line();
 712         }
 713       }
 714     }
 715   }
 716   return best_line;
 717 }
 718 
 719 
 720 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 721   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 722     Thread *thread = Thread::current();
 723     Symbol* klass_name = constants()->klass_name_at(klass_index);
 724     Handle loader(thread, method_holder()->class_loader());
 725     Handle prot  (thread, method_holder()->protection_domain());
 726     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 727   } else {
 728     return true;
 729   }
 730 }
 731 
 732 
 733 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 734   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 735   if (must_be_resolved) {
 736     // Make sure klass is resolved in constantpool.
 737     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 738   }
 739   return is_klass_loaded_by_klass_index(klass_index);
 740 }
 741 
 742 
 743 void Method::set_native_function(address function, bool post_event_flag) {
 744   assert(function != NULL, "use clear_native_function to unregister natives");
 745   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 746   address* native_function = native_function_addr();
 747 
 748   // We can see racers trying to place the same native function into place. Once
 749   // is plenty.
 750   address current = *native_function;
 751   if (current == function) return;
 752   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 753       function != NULL) {
 754     // native_method_throw_unsatisfied_link_error_entry() should only
 755     // be passed when post_event_flag is false.
 756     assert(function !=
 757       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 758       "post_event_flag mis-match");
 759 
 760     // post the bind event, and possible change the bind function
 761     JvmtiExport::post_native_method_bind(this, &function);
 762   }
 763   *native_function = function;
 764   // This function can be called more than once. We must make sure that we always
 765   // use the latest registered method -> check if a stub already has been generated.
 766   // If so, we have to make it not_entrant.
 767   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 768   if (nm != NULL) {
 769     nm->make_not_entrant();
 770   }
 771 }
 772 
 773 
 774 bool Method::has_native_function() const {
 775   if (is_method_handle_intrinsic())
 776     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 777   address func = native_function();
 778   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 779 }
 780 
 781 
 782 void Method::clear_native_function() {
 783   // Note: is_method_handle_intrinsic() is allowed here.
 784   set_native_function(
 785     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 786     !native_bind_event_is_interesting);
 787   clear_code();
 788 }
 789 
 790 address Method::critical_native_function() {
 791   methodHandle mh(this);
 792   return NativeLookup::lookup_critical_entry(mh);
 793 }
 794 
 795 
 796 void Method::set_signature_handler(address handler) {
 797   address* signature_handler =  signature_handler_addr();
 798   *signature_handler = handler;
 799 }
 800 
 801 
 802 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 803   if (PrintCompilation && report) {
 804     ttyLocker ttyl;
 805     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 806     if (comp_level == CompLevel_all) {
 807       tty->print("all levels ");
 808     } else {
 809       tty->print("levels ");
 810       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 811         tty->print("%d ", i);
 812       }
 813     }
 814     this->print_short_name(tty);
 815     int size = this->code_size();
 816     if (size > 0) {
 817       tty->print(" (%d bytes)", size);
 818     }
 819     if (reason != NULL) {
 820       tty->print("   %s", reason);
 821     }
 822     tty->cr();
 823   }
 824   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 825     ttyLocker ttyl;
 826     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 827                      os::current_thread_id(), is_osr, comp_level);
 828     if (reason != NULL) {
 829       xtty->print(" reason=\'%s\'", reason);
 830     }
 831     xtty->method(this);
 832     xtty->stamp();
 833     xtty->end_elem();
 834   }
 835 }
 836 
 837 bool Method::is_always_compilable() const {
 838   // Generated adapters must be compiled
 839   if (is_method_handle_intrinsic() && is_synthetic()) {
 840     assert(!is_not_c1_compilable(), "sanity check");
 841     assert(!is_not_c2_compilable(), "sanity check");
 842     return true;
 843   }
 844 
 845   return false;
 846 }
 847 
 848 bool Method::is_not_compilable(int comp_level) const {
 849   if (number_of_breakpoints() > 0)
 850     return true;
 851   if (is_always_compilable())
 852     return false;
 853   if (comp_level == CompLevel_any)
 854     return is_not_c1_compilable() || is_not_c2_compilable();
 855   if (is_c1_compile(comp_level))
 856     return is_not_c1_compilable();
 857   if (is_c2_compile(comp_level))
 858     return is_not_c2_compilable();
 859   return false;
 860 }
 861 
 862 // call this when compiler finds that this method is not compilable
 863 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 864   if (is_always_compilable()) {
 865     // Don't mark a method which should be always compilable
 866     return;
 867   }
 868   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 869   if (comp_level == CompLevel_all) {
 870     set_not_c1_compilable();
 871     set_not_c2_compilable();
 872   } else {
 873     if (is_c1_compile(comp_level))
 874       set_not_c1_compilable();
 875     if (is_c2_compile(comp_level))
 876       set_not_c2_compilable();
 877   }
 878   CompilationPolicy::policy()->disable_compilation(this);
 879   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 880 }
 881 
 882 bool Method::is_not_osr_compilable(int comp_level) const {
 883   if (is_not_compilable(comp_level))
 884     return true;
 885   if (comp_level == CompLevel_any)
 886     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 887   if (is_c1_compile(comp_level))
 888     return is_not_c1_osr_compilable();
 889   if (is_c2_compile(comp_level))
 890     return is_not_c2_osr_compilable();
 891   return false;
 892 }
 893 
 894 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 895   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 896   if (comp_level == CompLevel_all) {
 897     set_not_c1_osr_compilable();
 898     set_not_c2_osr_compilable();
 899   } else {
 900     if (is_c1_compile(comp_level))
 901       set_not_c1_osr_compilable();
 902     if (is_c2_compile(comp_level))
 903       set_not_c2_osr_compilable();
 904   }
 905   CompilationPolicy::policy()->disable_compilation(this);
 906   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 907 }
 908 
 909 // Revert to using the interpreter and clear out the nmethod
 910 void Method::clear_code() {
 911 
 912   // this may be NULL if c2i adapters have not been made yet
 913   // Only should happen at allocate time.
 914   if (adapter() == NULL) {
 915     _from_compiled_entry    = NULL;
 916   } else {
 917     _from_compiled_entry    = adapter()->get_c2i_entry();
 918   }
 919   OrderAccess::storestore();
 920   _from_interpreted_entry = _i2i_entry;
 921   OrderAccess::storestore();
 922   _code = NULL;
 923 }
 924 
 925 #if INCLUDE_CDS
 926 // Called by class data sharing to remove any entry points (which are not shared)
 927 void Method::unlink_method() {
 928   _code = NULL;
 929 
 930   assert(DumpSharedSpaces, "dump time only");
 931   // Set the values to what they should be at run time. Note that
 932   // this Method can no longer be executed during dump time.
 933   _i2i_entry = Interpreter::entry_for_cds_method(this);
 934   _from_interpreted_entry = _i2i_entry;
 935 
 936   if (is_native()) {
 937     *native_function_addr() = NULL;
 938     set_signature_handler(NULL);
 939   }
 940   NOT_PRODUCT(set_compiled_invocation_count(0);)
 941 
 942   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 943   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 944   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 945   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 946 
 947 
 948   // In case of DumpSharedSpaces, _method_data should always be NULL.
 949   assert(_method_data == NULL, "unexpected method data?");
 950 
 951   set_method_data(NULL);
 952   clear_method_counters();
 953 }
 954 #endif
 955 
 956 // Called when the method_holder is getting linked. Setup entrypoints so the method
 957 // is ready to be called from interpreter, compiler, and vtables.
 958 void Method::link_method(const methodHandle& h_method, TRAPS) {
 959   // If the code cache is full, we may reenter this function for the
 960   // leftover methods that weren't linked.
 961   if (is_shared()) {
 962     if (adapter() != NULL) return;
 963   } else {
 964     if (_i2i_entry != NULL) return;
 965 
 966     assert(adapter() == NULL, "init'd to NULL" );
 967   }
 968   assert( _code == NULL, "nothing compiled yet" );
 969 
 970   // Setup interpreter entrypoint
 971   assert(this == h_method(), "wrong h_method()" );
 972   address entry;
 973 
 974   if (this->is_shared()) {
 975     entry = Interpreter::entry_for_cds_method(h_method);
 976   } else {
 977     entry = Interpreter::entry_for_method(h_method);
 978   }
 979   assert(entry != NULL, "interpreter entry must be non-null");
 980   if (is_shared()) {
 981     assert(entry == _i2i_entry && entry == _from_interpreted_entry,
 982            "should be correctly set during dump time");
 983   } else {
 984     // Sets both _i2i_entry and _from_interpreted_entry
 985     set_interpreter_entry(entry);
 986   }
 987 
 988   // Don't overwrite already registered native entries.
 989   if (is_native() && !has_native_function()) {
 990     set_native_function(
 991       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 992       !native_bind_event_is_interesting);
 993   }
 994 
 995   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 996   // special handling of vtables.  An alternative is to make adapters more
 997   // lazily by calling make_adapter() from from_compiled_entry() for the
 998   // normal calls.  For vtable calls life gets more complicated.  When a
 999   // call-site goes mega-morphic we need adapters in all methods which can be
1000   // called from the vtable.  We need adapters on such methods that get loaded
1001   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1002   // problem we'll make these lazily later.
1003   (void) make_adapters(h_method, CHECK);
1004 
1005   // ONLY USE the h_method now as make_adapter may have blocked
1006 
1007 }
1008 
1009 address Method::make_adapters(methodHandle mh, TRAPS) {
1010   // Adapters for compiled code are made eagerly here.  They are fairly
1011   // small (generally < 100 bytes) and quick to make (and cached and shared)
1012   // so making them eagerly shouldn't be too expensive.
1013   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1014   if (adapter == NULL ) {
1015     if (!is_init_completed()) {
1016       // Don't throw exceptions during VM initialization because java.lang.* classes
1017       // might not have been initialized, causing problems when constructing the
1018       // Java exception object.
1019       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1020     } else {
1021       THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1022     }
1023   }
1024 
1025   if (mh->is_shared()) {
1026     assert(mh->adapter() == adapter, "must be");
1027     assert(mh->_from_compiled_entry != NULL, "must be"); // FIXME, the instructions also not NULL
1028   } else {
1029     mh->set_adapter_entry(adapter);
1030     mh->_from_compiled_entry = adapter->get_c2i_entry();
1031   }
1032   return adapter->get_c2i_entry();
1033 }
1034 
1035 void Method::restore_unshareable_info(TRAPS) {
1036   // Since restore_unshareable_info can be called more than once for a method, don't
1037   // redo any work.   If this field is restored, there is nothing to do.
1038   if (_from_compiled_entry == NULL) {
1039     // restore method's vtable by calling a virtual function
1040     restore_vtable();
1041 
1042     methodHandle mh(THREAD, this);
1043     link_method(mh, CHECK);
1044   }
1045 }
1046 
1047 volatile address Method::from_compiled_entry_no_trampoline() const {
1048   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1049   if (code) {
1050     return code->verified_entry_point();
1051   } else {
1052     return adapter()->get_c2i_entry();
1053   }
1054 }
1055 
1056 // The verified_code_entry() must be called when a invoke is resolved
1057 // on this method.
1058 
1059 // It returns the compiled code entry point, after asserting not null.
1060 // This function is called after potential safepoints so that nmethod
1061 // or adapter that it points to is still live and valid.
1062 // This function must not hit a safepoint!
1063 address Method::verified_code_entry() {
1064   debug_only(NoSafepointVerifier nsv;)
1065   assert(_from_compiled_entry != NULL, "must be set");
1066   return _from_compiled_entry;
1067 }
1068 
1069 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1070 // (could be racing a deopt).
1071 // Not inline to avoid circular ref.
1072 bool Method::check_code() const {
1073   // cached in a register or local.  There's a race on the value of the field.
1074   CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1075   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1076 }
1077 
1078 // Install compiled code.  Instantly it can execute.
1079 void Method::set_code(methodHandle mh, CompiledMethod *code) {
1080   assert( code, "use clear_code to remove code" );
1081   assert( mh->check_code(), "" );
1082 
1083   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1084 
1085   // These writes must happen in this order, because the interpreter will
1086   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1087   // which jumps to _from_compiled_entry.
1088   mh->_code = code;             // Assign before allowing compiled code to exec
1089 
1090   int comp_level = code->comp_level();
1091   // In theory there could be a race here. In practice it is unlikely
1092   // and not worth worrying about.
1093   if (comp_level > mh->highest_comp_level()) {
1094     mh->set_highest_comp_level(comp_level);
1095   }
1096 
1097   OrderAccess::storestore();
1098 #ifdef SHARK
1099   mh->_from_interpreted_entry = code->insts_begin();
1100 #else //!SHARK
1101   mh->_from_compiled_entry = code->verified_entry_point();
1102   OrderAccess::storestore();
1103   // Instantly compiled code can execute.
1104   if (!mh->is_method_handle_intrinsic())
1105     mh->_from_interpreted_entry = mh->get_i2c_entry();
1106 #endif //!SHARK
1107 }
1108 
1109 
1110 bool Method::is_overridden_in(Klass* k) const {
1111   InstanceKlass* ik = InstanceKlass::cast(k);
1112 
1113   if (ik->is_interface()) return false;
1114 
1115   // If method is an interface, we skip it - except if it
1116   // is a miranda method
1117   if (method_holder()->is_interface()) {
1118     // Check that method is not a miranda method
1119     if (ik->lookup_method(name(), signature()) == NULL) {
1120       // No implementation exist - so miranda method
1121       return false;
1122     }
1123     return true;
1124   }
1125 
1126   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1127   assert(ik->vtable() != NULL, "vtable should exist");
1128   if (!has_vtable_index()) {
1129     return false;
1130   } else {
1131     Method* vt_m = ik->method_at_vtable(vtable_index());
1132     return vt_m != this;
1133   }
1134 }
1135 
1136 
1137 // give advice about whether this Method* should be cached or not
1138 bool Method::should_not_be_cached() const {
1139   if (is_old()) {
1140     // This method has been redefined. It is either EMCP or obsolete
1141     // and we don't want to cache it because that would pin the method
1142     // down and prevent it from being collectible if and when it
1143     // finishes executing.
1144     return true;
1145   }
1146 
1147   // caching this method should be just fine
1148   return false;
1149 }
1150 
1151 
1152 /**
1153  *  Returns true if this is one of the specially treated methods for
1154  *  security related stack walks (like Reflection.getCallerClass).
1155  */
1156 bool Method::is_ignored_by_security_stack_walk() const {
1157   if (intrinsic_id() == vmIntrinsics::_invoke) {
1158     // This is Method.invoke() -- ignore it
1159     return true;
1160   }
1161   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1162     // This is an auxilary frame -- ignore it
1163     return true;
1164   }
1165   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1166     // This is an internal adapter frame for method handles -- ignore it
1167     return true;
1168   }
1169   return false;
1170 }
1171 
1172 
1173 // Constant pool structure for invoke methods:
1174 enum {
1175   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1176   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1177   _imcp_limit
1178 };
1179 
1180 // Test if this method is an MH adapter frame generated by Java code.
1181 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1182 bool Method::is_compiled_lambda_form() const {
1183   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1184 }
1185 
1186 // Test if this method is an internal MH primitive method.
1187 bool Method::is_method_handle_intrinsic() const {
1188   vmIntrinsics::ID iid = intrinsic_id();
1189   return (MethodHandles::is_signature_polymorphic(iid) &&
1190           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1191 }
1192 
1193 bool Method::has_member_arg() const {
1194   vmIntrinsics::ID iid = intrinsic_id();
1195   return (MethodHandles::is_signature_polymorphic(iid) &&
1196           MethodHandles::has_member_arg(iid));
1197 }
1198 
1199 // Make an instance of a signature-polymorphic internal MH primitive.
1200 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1201                                                          Symbol* signature,
1202                                                          TRAPS) {
1203   ResourceMark rm;
1204   methodHandle empty;
1205 
1206   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1207   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1208   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1209   if (TraceMethodHandles) {
1210     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1211   }
1212 
1213   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1214   name->increment_refcount();
1215   signature->increment_refcount();
1216 
1217   int cp_length = _imcp_limit;
1218   ClassLoaderData* loader_data = holder->class_loader_data();
1219   constantPoolHandle cp;
1220   {
1221     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1222     cp = constantPoolHandle(THREAD, cp_oop);
1223   }
1224   cp->set_pool_holder(InstanceKlass::cast(holder()));
1225   cp->symbol_at_put(_imcp_invoke_name,       name);
1226   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1227   cp->set_has_preresolution();
1228 
1229   // decide on access bits:  public or not?
1230   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1231   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1232   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1233   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1234 
1235   methodHandle m;
1236   {
1237     InlineTableSizes sizes;
1238     Method* m_oop = Method::allocate(loader_data, 0,
1239                                      accessFlags_from(flags_bits), &sizes,
1240                                      ConstMethod::NORMAL, CHECK_(empty));
1241     m = methodHandle(THREAD, m_oop);
1242   }
1243   m->set_constants(cp());
1244   m->set_name_index(_imcp_invoke_name);
1245   m->set_signature_index(_imcp_invoke_signature);
1246   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1247   assert(m->signature() == signature, "");
1248   ResultTypeFinder rtf(signature);
1249   m->constMethod()->set_result_type(rtf.type());
1250   m->compute_size_of_parameters(THREAD);
1251   m->init_intrinsic_id();
1252   assert(m->is_method_handle_intrinsic(), "");
1253 #ifdef ASSERT
1254   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1255   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1256   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1257 #endif //ASSERT
1258 
1259   // Finally, set up its entry points.
1260   assert(m->can_be_statically_bound(), "");
1261   m->set_vtable_index(Method::nonvirtual_vtable_index);
1262   m->link_method(m, CHECK_(empty));
1263 
1264   if (TraceMethodHandles && (Verbose || WizardMode)) {
1265     ttyLocker ttyl;
1266     m->print_on(tty);
1267   }
1268 
1269   return m;
1270 }
1271 
1272 Klass* Method::check_non_bcp_klass(Klass* klass) {
1273   if (klass != NULL && klass->class_loader() != NULL) {
1274     if (klass->is_objArray_klass())
1275       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1276     return klass;
1277   }
1278   return NULL;
1279 }
1280 
1281 
1282 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1283                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1284   // Code below does not work for native methods - they should never get rewritten anyway
1285   assert(!m->is_native(), "cannot rewrite native methods");
1286   // Allocate new Method*
1287   AccessFlags flags = m->access_flags();
1288 
1289   ConstMethod* cm = m->constMethod();
1290   int checked_exceptions_len = cm->checked_exceptions_length();
1291   int localvariable_len = cm->localvariable_table_length();
1292   int exception_table_len = cm->exception_table_length();
1293   int method_parameters_len = cm->method_parameters_length();
1294   int method_annotations_len = cm->method_annotations_length();
1295   int parameter_annotations_len = cm->parameter_annotations_length();
1296   int type_annotations_len = cm->type_annotations_length();
1297   int default_annotations_len = cm->default_annotations_length();
1298 
1299   InlineTableSizes sizes(
1300       localvariable_len,
1301       new_compressed_linenumber_size,
1302       exception_table_len,
1303       checked_exceptions_len,
1304       method_parameters_len,
1305       cm->generic_signature_index(),
1306       method_annotations_len,
1307       parameter_annotations_len,
1308       type_annotations_len,
1309       default_annotations_len,
1310       0);
1311 
1312   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1313   Method* newm_oop = Method::allocate(loader_data,
1314                                       new_code_length,
1315                                       flags,
1316                                       &sizes,
1317                                       m->method_type(),
1318                                       CHECK_(methodHandle()));
1319   methodHandle newm (THREAD, newm_oop);
1320 
1321   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1322   ConstMethod* newcm = newm->constMethod();
1323   int new_const_method_size = newm->constMethod()->size();
1324 
1325   memcpy(newm(), m(), sizeof(Method));
1326 
1327   // Create shallow copy of ConstMethod.
1328   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1329 
1330   // Reset correct method/const method, method size, and parameter info
1331   newm->set_constMethod(newcm);
1332   newm->constMethod()->set_code_size(new_code_length);
1333   newm->constMethod()->set_constMethod_size(new_const_method_size);
1334   assert(newm->code_size() == new_code_length, "check");
1335   assert(newm->method_parameters_length() == method_parameters_len, "check");
1336   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1337   assert(newm->exception_table_length() == exception_table_len, "check");
1338   assert(newm->localvariable_table_length() == localvariable_len, "check");
1339   // Copy new byte codes
1340   memcpy(newm->code_base(), new_code, new_code_length);
1341   // Copy line number table
1342   if (new_compressed_linenumber_size > 0) {
1343     memcpy(newm->compressed_linenumber_table(),
1344            new_compressed_linenumber_table,
1345            new_compressed_linenumber_size);
1346   }
1347   // Copy method_parameters
1348   if (method_parameters_len > 0) {
1349     memcpy(newm->method_parameters_start(),
1350            m->method_parameters_start(),
1351            method_parameters_len * sizeof(MethodParametersElement));
1352   }
1353   // Copy checked_exceptions
1354   if (checked_exceptions_len > 0) {
1355     memcpy(newm->checked_exceptions_start(),
1356            m->checked_exceptions_start(),
1357            checked_exceptions_len * sizeof(CheckedExceptionElement));
1358   }
1359   // Copy exception table
1360   if (exception_table_len > 0) {
1361     memcpy(newm->exception_table_start(),
1362            m->exception_table_start(),
1363            exception_table_len * sizeof(ExceptionTableElement));
1364   }
1365   // Copy local variable number table
1366   if (localvariable_len > 0) {
1367     memcpy(newm->localvariable_table_start(),
1368            m->localvariable_table_start(),
1369            localvariable_len * sizeof(LocalVariableTableElement));
1370   }
1371   // Copy stackmap table
1372   if (m->has_stackmap_table()) {
1373     int code_attribute_length = m->stackmap_data()->length();
1374     Array<u1>* stackmap_data =
1375       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1376     memcpy((void*)stackmap_data->adr_at(0),
1377            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1378     newm->set_stackmap_data(stackmap_data);
1379   }
1380 
1381   // copy annotations over to new method
1382   newcm->copy_annotations_from(cm);
1383   return newm;
1384 }
1385 
1386 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1387   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1388   // because we are not loading from core libraries
1389   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1390   // which does not use the class default class loader so we check for its loader here
1391   const InstanceKlass* ik = InstanceKlass::cast(holder);
1392   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1393     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1394   }
1395 
1396   // see if the klass name is well-known:
1397   Symbol* klass_name = ik->name();
1398   return vmSymbols::find_sid(klass_name);
1399 }
1400 
1401 void Method::init_intrinsic_id() {
1402   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1403   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1404   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1405   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1406 
1407   // the klass name is well-known:
1408   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1409   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1410 
1411   // ditto for method and signature:
1412   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1413   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1414       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1415       && name_id == vmSymbols::NO_SID) {
1416     return;
1417   }
1418   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1419   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1420       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1421       && sig_id == vmSymbols::NO_SID) {
1422     return;
1423   }
1424   jshort flags = access_flags().as_short();
1425 
1426   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1427   if (id != vmIntrinsics::_none) {
1428     set_intrinsic_id(id);
1429     if (id == vmIntrinsics::_Class_cast) {
1430       // Even if the intrinsic is rejected, we want to inline this simple method.
1431       set_force_inline(true);
1432     }
1433     return;
1434   }
1435 
1436   // A few slightly irregular cases:
1437   switch (klass_id) {
1438   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1439     // Second chance: check in regular Math.
1440     switch (name_id) {
1441     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1442     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1443     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1444       // pretend it is the corresponding method in the non-strict class:
1445       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1446       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1447       break;
1448     }
1449     break;
1450 
1451   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1452   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1453   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1454     if (!is_native())  break;
1455     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1456     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1457       id = vmIntrinsics::_none;
1458     break;
1459   }
1460 
1461   if (id != vmIntrinsics::_none) {
1462     // Set up its iid.  It is an alias method.
1463     set_intrinsic_id(id);
1464     return;
1465   }
1466 }
1467 
1468 // These two methods are static since a GC may move the Method
1469 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1470   if (!THREAD->can_call_java()) {
1471     // There is nothing useful this routine can do from within the Compile thread.
1472     // Hopefully, the signature contains only well-known classes.
1473     // We could scan for this and return true/false, but the caller won't care.
1474     return false;
1475   }
1476   bool sig_is_loaded = true;
1477   Handle class_loader(THREAD, m->method_holder()->class_loader());
1478   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1479   ResourceMark rm(THREAD);
1480   Symbol*  signature = m->signature();
1481   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1482     if (ss.is_object()) {
1483       Symbol* sym = ss.as_symbol(CHECK_(false));
1484       Symbol*  name  = sym;
1485       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1486                                              protection_domain, THREAD);
1487       // We are loading classes eagerly. If a ClassNotFoundException or
1488       // a LinkageError was generated, be sure to ignore it.
1489       if (HAS_PENDING_EXCEPTION) {
1490         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1491             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1492           CLEAR_PENDING_EXCEPTION;
1493         } else {
1494           return false;
1495         }
1496       }
1497       if( klass == NULL) { sig_is_loaded = false; }
1498     }
1499   }
1500   return sig_is_loaded;
1501 }
1502 
1503 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1504   Handle class_loader(THREAD, m->method_holder()->class_loader());
1505   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1506   ResourceMark rm(THREAD);
1507   Symbol*  signature = m->signature();
1508   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1509     if (ss.type() == T_OBJECT) {
1510       Symbol* name = ss.as_symbol_or_null();
1511       if (name == NULL) return true;
1512       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1513       if (klass == NULL) return true;
1514     }
1515   }
1516   return false;
1517 }
1518 
1519 // Exposed so field engineers can debug VM
1520 void Method::print_short_name(outputStream* st) {
1521   ResourceMark rm;
1522 #ifdef PRODUCT
1523   st->print(" %s::", method_holder()->external_name());
1524 #else
1525   st->print(" %s::", method_holder()->internal_name());
1526 #endif
1527   name()->print_symbol_on(st);
1528   if (WizardMode) signature()->print_symbol_on(st);
1529   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1530     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1531 }
1532 
1533 // Comparer for sorting an object array containing
1534 // Method*s.
1535 static int method_comparator(Method* a, Method* b) {
1536   return a->name()->fast_compare(b->name());
1537 }
1538 
1539 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1540 // default_methods also uses this without the ordering for fast find_method
1541 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1542   int length = methods->length();
1543   if (length > 1) {
1544     {
1545       NoSafepointVerifier nsv;
1546       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1547     }
1548     // Reset method ordering
1549     if (set_idnums) {
1550       for (int i = 0; i < length; i++) {
1551         Method* m = methods->at(i);
1552         m->set_method_idnum(i);
1553         m->set_orig_method_idnum(i);
1554       }
1555     }
1556   }
1557 }
1558 
1559 //-----------------------------------------------------------------------------------
1560 // Non-product code unless JVM/TI needs it
1561 
1562 #if !defined(PRODUCT) || INCLUDE_JVMTI
1563 class SignatureTypePrinter : public SignatureTypeNames {
1564  private:
1565   outputStream* _st;
1566   bool _use_separator;
1567 
1568   void type_name(const char* name) {
1569     if (_use_separator) _st->print(", ");
1570     _st->print("%s", name);
1571     _use_separator = true;
1572   }
1573 
1574  public:
1575   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1576     _st = st;
1577     _use_separator = false;
1578   }
1579 
1580   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1581   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1582 };
1583 
1584 
1585 void Method::print_name(outputStream* st) {
1586   Thread *thread = Thread::current();
1587   ResourceMark rm(thread);
1588   st->print("%s ", is_static() ? "static" : "virtual");
1589   if (WizardMode) {
1590     st->print("%s.", method_holder()->internal_name());
1591     name()->print_symbol_on(st);
1592     signature()->print_symbol_on(st);
1593   } else {
1594     SignatureTypePrinter sig(signature(), st);
1595     sig.print_returntype();
1596     st->print(" %s.", method_holder()->internal_name());
1597     name()->print_symbol_on(st);
1598     st->print("(");
1599     sig.print_parameters();
1600     st->print(")");
1601   }
1602 }
1603 #endif // !PRODUCT || INCLUDE_JVMTI
1604 
1605 
1606 void Method::print_codes_on(outputStream* st) const {
1607   print_codes_on(0, code_size(), st);
1608 }
1609 
1610 void Method::print_codes_on(int from, int to, outputStream* st) const {
1611   Thread *thread = Thread::current();
1612   ResourceMark rm(thread);
1613   methodHandle mh (thread, (Method*)this);
1614   BytecodeStream s(mh);
1615   s.set_interval(from, to);
1616   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1617   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1618 }
1619 
1620 
1621 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1622 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1623 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1624 // as end-of-stream terminator.
1625 
1626 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1627   // bci and line number does not compress into single byte.
1628   // Write out escape character and use regular compression for bci and line number.
1629   write_byte((jubyte)0xFF);
1630   write_signed_int(bci_delta);
1631   write_signed_int(line_delta);
1632 }
1633 
1634 // See comment in method.hpp which explains why this exists.
1635 #if defined(_M_AMD64) && _MSC_VER >= 1400
1636 #pragma optimize("", off)
1637 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1638   write_pair_inline(bci, line);
1639 }
1640 #pragma optimize("", on)
1641 #endif
1642 
1643 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1644   _bci = 0;
1645   _line = 0;
1646 };
1647 
1648 
1649 bool CompressedLineNumberReadStream::read_pair() {
1650   jubyte next = read_byte();
1651   // Check for terminator
1652   if (next == 0) return false;
1653   if (next == 0xFF) {
1654     // Escape character, regular compression used
1655     _bci  += read_signed_int();
1656     _line += read_signed_int();
1657   } else {
1658     // Single byte compression used
1659     _bci  += next >> 3;
1660     _line += next & 0x7;
1661   }
1662   return true;
1663 }
1664 
1665 #if INCLUDE_JVMTI
1666 
1667 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1668   BreakpointInfo* bp = method_holder()->breakpoints();
1669   for (; bp != NULL; bp = bp->next()) {
1670     if (bp->match(this, bci)) {
1671       return bp->orig_bytecode();
1672     }
1673   }
1674   {
1675     ResourceMark rm;
1676     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1677   }
1678   return Bytecodes::_shouldnotreachhere;
1679 }
1680 
1681 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1682   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1683   BreakpointInfo* bp = method_holder()->breakpoints();
1684   for (; bp != NULL; bp = bp->next()) {
1685     if (bp->match(this, bci)) {
1686       bp->set_orig_bytecode(code);
1687       // and continue, in case there is more than one
1688     }
1689   }
1690 }
1691 
1692 void Method::set_breakpoint(int bci) {
1693   InstanceKlass* ik = method_holder();
1694   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1695   bp->set_next(ik->breakpoints());
1696   ik->set_breakpoints(bp);
1697   // do this last:
1698   bp->set(this);
1699 }
1700 
1701 static void clear_matches(Method* m, int bci) {
1702   InstanceKlass* ik = m->method_holder();
1703   BreakpointInfo* prev_bp = NULL;
1704   BreakpointInfo* next_bp;
1705   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1706     next_bp = bp->next();
1707     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1708     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1709       // do this first:
1710       bp->clear(m);
1711       // unhook it
1712       if (prev_bp != NULL)
1713         prev_bp->set_next(next_bp);
1714       else
1715         ik->set_breakpoints(next_bp);
1716       delete bp;
1717       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1718       // at same location. So we have multiple matching (method_index and bci)
1719       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1720       // breakpoint for clear_breakpoint request and keep all other method versions
1721       // BreakpointInfo for future clear_breakpoint request.
1722       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1723       // which is being called when class is unloaded. We delete all the Breakpoint
1724       // information for all versions of method. We may not correctly restore the original
1725       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1726       // so these methods won't be used anymore.
1727       if (bci >= 0) {
1728         break;
1729       }
1730     } else {
1731       // This one is a keeper.
1732       prev_bp = bp;
1733     }
1734   }
1735 }
1736 
1737 void Method::clear_breakpoint(int bci) {
1738   assert(bci >= 0, "");
1739   clear_matches(this, bci);
1740 }
1741 
1742 void Method::clear_all_breakpoints() {
1743   clear_matches(this, -1);
1744 }
1745 
1746 #endif // INCLUDE_JVMTI
1747 
1748 int Method::invocation_count() {
1749   MethodCounters *mcs = method_counters();
1750   if (TieredCompilation) {
1751     MethodData* const mdo = method_data();
1752     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1753         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1754       return InvocationCounter::count_limit;
1755     } else {
1756       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1757              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1758     }
1759   } else {
1760     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1761   }
1762 }
1763 
1764 int Method::backedge_count() {
1765   MethodCounters *mcs = method_counters();
1766   if (TieredCompilation) {
1767     MethodData* const mdo = method_data();
1768     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1769         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1770       return InvocationCounter::count_limit;
1771     } else {
1772       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1773              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1774     }
1775   } else {
1776     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1777   }
1778 }
1779 
1780 int Method::highest_comp_level() const {
1781   const MethodCounters* mcs = method_counters();
1782   if (mcs != NULL) {
1783     return mcs->highest_comp_level();
1784   } else {
1785     return CompLevel_none;
1786   }
1787 }
1788 
1789 int Method::highest_osr_comp_level() const {
1790   const MethodCounters* mcs = method_counters();
1791   if (mcs != NULL) {
1792     return mcs->highest_osr_comp_level();
1793   } else {
1794     return CompLevel_none;
1795   }
1796 }
1797 
1798 void Method::set_highest_comp_level(int level) {
1799   MethodCounters* mcs = method_counters();
1800   if (mcs != NULL) {
1801     mcs->set_highest_comp_level(level);
1802   }
1803 }
1804 
1805 void Method::set_highest_osr_comp_level(int level) {
1806   MethodCounters* mcs = method_counters();
1807   if (mcs != NULL) {
1808     mcs->set_highest_osr_comp_level(level);
1809   }
1810 }
1811 
1812 #if INCLUDE_JVMTI
1813 
1814 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1815   _bci = bci;
1816   _name_index = m->name_index();
1817   _signature_index = m->signature_index();
1818   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1819   if (_orig_bytecode == Bytecodes::_breakpoint)
1820     _orig_bytecode = m->orig_bytecode_at(_bci);
1821   _next = NULL;
1822 }
1823 
1824 void BreakpointInfo::set(Method* method) {
1825 #ifdef ASSERT
1826   {
1827     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1828     if (code == Bytecodes::_breakpoint)
1829       code = method->orig_bytecode_at(_bci);
1830     assert(orig_bytecode() == code, "original bytecode must be the same");
1831   }
1832 #endif
1833   Thread *thread = Thread::current();
1834   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1835   method->incr_number_of_breakpoints(thread);
1836   SystemDictionary::notice_modification();
1837   {
1838     // Deoptimize all dependents on this method
1839     HandleMark hm(thread);
1840     methodHandle mh(thread, method);
1841     CodeCache::flush_dependents_on_method(mh);
1842   }
1843 }
1844 
1845 void BreakpointInfo::clear(Method* method) {
1846   *method->bcp_from(_bci) = orig_bytecode();
1847   assert(method->number_of_breakpoints() > 0, "must not go negative");
1848   method->decr_number_of_breakpoints(Thread::current());
1849 }
1850 
1851 #endif // INCLUDE_JVMTI
1852 
1853 // jmethodID handling
1854 
1855 // This is a block allocating object, sort of like JNIHandleBlock, only a
1856 // lot simpler.
1857 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1858 // never get rid of it.
1859 
1860 static const int min_block_size = 8;
1861 
1862 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1863   friend class JNIMethodBlock;
1864   Method**        _methods;
1865   int             _number_of_methods;
1866   int             _top;
1867   JNIMethodBlockNode* _next;
1868 
1869  public:
1870 
1871   JNIMethodBlockNode(int num_methods = min_block_size);
1872 
1873   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1874 
1875   void ensure_methods(int num_addl_methods) {
1876     if (_top < _number_of_methods) {
1877       num_addl_methods -= _number_of_methods - _top;
1878       if (num_addl_methods <= 0) {
1879         return;
1880       }
1881     }
1882     if (_next == NULL) {
1883       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1884     } else {
1885       _next->ensure_methods(num_addl_methods);
1886     }
1887   }
1888 };
1889 
1890 class JNIMethodBlock : public CHeapObj<mtClass> {
1891   JNIMethodBlockNode _head;
1892   JNIMethodBlockNode *_last_free;
1893  public:
1894   static Method* const _free_method;
1895 
1896   JNIMethodBlock(int initial_capacity = min_block_size)
1897       : _head(initial_capacity), _last_free(&_head) {}
1898 
1899   void ensure_methods(int num_addl_methods) {
1900     _last_free->ensure_methods(num_addl_methods);
1901   }
1902 
1903   Method** add_method(Method* m) {
1904     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1905       if (b->_top < b->_number_of_methods) {
1906         // top points to the next free entry.
1907         int i = b->_top;
1908         b->_methods[i] = m;
1909         b->_top++;
1910         _last_free = b;
1911         return &(b->_methods[i]);
1912       } else if (b->_top == b->_number_of_methods) {
1913         // if the next free entry ran off the block see if there's a free entry
1914         for (int i = 0; i < b->_number_of_methods; i++) {
1915           if (b->_methods[i] == _free_method) {
1916             b->_methods[i] = m;
1917             _last_free = b;
1918             return &(b->_methods[i]);
1919           }
1920         }
1921         // Only check each block once for frees.  They're very unlikely.
1922         // Increment top past the end of the block.
1923         b->_top++;
1924       }
1925       // need to allocate a next block.
1926       if (b->_next == NULL) {
1927         b->_next = _last_free = new JNIMethodBlockNode();
1928       }
1929     }
1930     guarantee(false, "Should always allocate a free block");
1931     return NULL;
1932   }
1933 
1934   bool contains(Method** m) {
1935     if (m == NULL) return false;
1936     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1937       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
1938         // This is a bit of extra checking, for two reasons.  One is
1939         // that contains() deals with pointers that are passed in by
1940         // JNI code, so making sure that the pointer is aligned
1941         // correctly is valuable.  The other is that <= and > are
1942         // technically not defined on pointers, so the if guard can
1943         // pass spuriously; no modern compiler is likely to make that
1944         // a problem, though (and if one did, the guard could also
1945         // fail spuriously, which would be bad).
1946         ptrdiff_t idx = m - b->_methods;
1947         if (b->_methods + idx == m) {
1948           return true;
1949         }
1950       }
1951     }
1952     return false;  // not found
1953   }
1954 
1955   // Doesn't really destroy it, just marks it as free so it can be reused.
1956   void destroy_method(Method** m) {
1957 #ifdef ASSERT
1958     assert(contains(m), "should be a methodID");
1959 #endif // ASSERT
1960     *m = _free_method;
1961   }
1962 
1963   // During class unloading the methods are cleared, which is different
1964   // than freed.
1965   void clear_all_methods() {
1966     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1967       for (int i = 0; i< b->_number_of_methods; i++) {
1968         b->_methods[i] = NULL;
1969       }
1970     }
1971   }
1972 #ifndef PRODUCT
1973   int count_methods() {
1974     // count all allocated methods
1975     int count = 0;
1976     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1977       for (int i = 0; i< b->_number_of_methods; i++) {
1978         if (b->_methods[i] != _free_method) count++;
1979       }
1980     }
1981     return count;
1982   }
1983 #endif // PRODUCT
1984 };
1985 
1986 // Something that can't be mistaken for an address or a markOop
1987 Method* const JNIMethodBlock::_free_method = (Method*)55;
1988 
1989 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
1990   _number_of_methods = MAX2(num_methods, min_block_size);
1991   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
1992   for (int i = 0; i < _number_of_methods; i++) {
1993     _methods[i] = JNIMethodBlock::_free_method;
1994   }
1995 }
1996 
1997 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
1998   ClassLoaderData* cld = loader_data;
1999   if (!SafepointSynchronize::is_at_safepoint()) {
2000     // Have to add jmethod_ids() to class loader data thread-safely.
2001     // Also have to add the method to the list safely, which the cld lock
2002     // protects as well.
2003     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2004     if (cld->jmethod_ids() == NULL) {
2005       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2006     } else {
2007       cld->jmethod_ids()->ensure_methods(capacity);
2008     }
2009   } else {
2010     // At safepoint, we are single threaded and can set this.
2011     if (cld->jmethod_ids() == NULL) {
2012       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2013     } else {
2014       cld->jmethod_ids()->ensure_methods(capacity);
2015     }
2016   }
2017 }
2018 
2019 // Add a method id to the jmethod_ids
2020 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2021   ClassLoaderData* cld = loader_data;
2022 
2023   if (!SafepointSynchronize::is_at_safepoint()) {
2024     // Have to add jmethod_ids() to class loader data thread-safely.
2025     // Also have to add the method to the list safely, which the cld lock
2026     // protects as well.
2027     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2028     if (cld->jmethod_ids() == NULL) {
2029       cld->set_jmethod_ids(new JNIMethodBlock());
2030     }
2031     // jmethodID is a pointer to Method*
2032     return (jmethodID)cld->jmethod_ids()->add_method(m);
2033   } else {
2034     // At safepoint, we are single threaded and can set this.
2035     if (cld->jmethod_ids() == NULL) {
2036       cld->set_jmethod_ids(new JNIMethodBlock());
2037     }
2038     // jmethodID is a pointer to Method*
2039     return (jmethodID)cld->jmethod_ids()->add_method(m);
2040   }
2041 }
2042 
2043 // Mark a jmethodID as free.  This is called when there is a data race in
2044 // InstanceKlass while creating the jmethodID cache.
2045 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2046   ClassLoaderData* cld = loader_data;
2047   Method** ptr = (Method**)m;
2048   assert(cld->jmethod_ids() != NULL, "should have method handles");
2049   cld->jmethod_ids()->destroy_method(ptr);
2050 }
2051 
2052 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2053   // Can't assert the method_holder is the same because the new method has the
2054   // scratch method holder.
2055   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2056            == new_method->method_holder()->class_loader(),
2057          "changing to a different class loader");
2058   // Just change the method in place, jmethodID pointer doesn't change.
2059   *((Method**)jmid) = new_method;
2060 }
2061 
2062 bool Method::is_method_id(jmethodID mid) {
2063   Method* m = resolve_jmethod_id(mid);
2064   assert(m != NULL, "should be called with non-null method");
2065   InstanceKlass* ik = m->method_holder();
2066   ClassLoaderData* cld = ik->class_loader_data();
2067   if (cld->jmethod_ids() == NULL) return false;
2068   return (cld->jmethod_ids()->contains((Method**)mid));
2069 }
2070 
2071 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2072   if (mid == NULL) return NULL;
2073   Method* o = resolve_jmethod_id(mid);
2074   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2075     return NULL;
2076   }
2077   return o;
2078 };
2079 
2080 void Method::set_on_stack(const bool value) {
2081   // Set both the method itself and its constant pool.  The constant pool
2082   // on stack means some method referring to it is also on the stack.
2083   constants()->set_on_stack(value);
2084 
2085   bool already_set = on_stack();
2086   _access_flags.set_on_stack(value);
2087   if (value && !already_set) {
2088     MetadataOnStackMark::record(this);
2089   }
2090 }
2091 
2092 // Called when the class loader is unloaded to make all methods weak.
2093 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2094   loader_data->jmethod_ids()->clear_all_methods();
2095 }
2096 
2097 bool Method::has_method_vptr(const void* ptr) {
2098   Method m;
2099   // This assumes that the vtbl pointer is the first word of a C++ object.
2100   // This assumption is also in universe.cpp patch_klass_vtble
2101   return dereference_vptr(&m) == dereference_vptr(ptr);
2102 }
2103 
2104 // Check that this pointer is valid by checking that the vtbl pointer matches
2105 bool Method::is_valid_method() const {
2106   if (this == NULL) {
2107     return false;
2108   } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2109     // Quick sanity check on pointer.
2110     return false;
2111   } else if (!is_metaspace_object()) {
2112     return false;
2113   } else {
2114     return has_method_vptr((const void*)this);
2115   }
2116 }
2117 
2118 #ifndef PRODUCT
2119 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2120   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2121 }
2122 #endif // PRODUCT
2123 
2124 
2125 // Printing
2126 
2127 #ifndef PRODUCT
2128 
2129 void Method::print_on(outputStream* st) const {
2130   ResourceMark rm;
2131   assert(is_method(), "must be method");
2132   st->print_cr("%s", internal_name());
2133   // get the effect of PrintOopAddress, always, for methods:
2134   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2135   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2136   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2137   constants()->print_value_on(st); st->cr();
2138   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2139   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2140   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2141   st->print_cr(" - max stack:         %d",   max_stack());
2142   st->print_cr(" - max locals:        %d",   max_locals());
2143   st->print_cr(" - size of params:    %d",   size_of_parameters());
2144   st->print_cr(" - method size:       %d",   method_size());
2145   if (intrinsic_id() != vmIntrinsics::_none)
2146     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2147   if (highest_comp_level() != CompLevel_none)
2148     st->print_cr(" - highest level:     %d", highest_comp_level());
2149   st->print_cr(" - vtable index:      %d",   _vtable_index);
2150   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2151   st->print(   " - adapters:          ");
2152   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2153   if (a == NULL)
2154     st->print_cr(INTPTR_FORMAT, p2i(a));
2155   else
2156     a->print_adapter_on(st);
2157   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2158   st->print_cr(" - code size:         %d",   code_size());
2159   if (code_size() != 0) {
2160     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2161     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2162   }
2163   if (method_data() != NULL) {
2164     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2165   }
2166   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2167   if (checked_exceptions_length() > 0) {
2168     CheckedExceptionElement* table = checked_exceptions_start();
2169     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2170     if (Verbose) {
2171       for (int i = 0; i < checked_exceptions_length(); i++) {
2172         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2173       }
2174     }
2175   }
2176   if (has_linenumber_table()) {
2177     u_char* table = compressed_linenumber_table();
2178     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2179     if (Verbose) {
2180       CompressedLineNumberReadStream stream(table);
2181       while (stream.read_pair()) {
2182         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2183       }
2184     }
2185   }
2186   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2187   if (localvariable_table_length() > 0) {
2188     LocalVariableTableElement* table = localvariable_table_start();
2189     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2190     if (Verbose) {
2191       for (int i = 0; i < localvariable_table_length(); i++) {
2192         int bci = table[i].start_bci;
2193         int len = table[i].length;
2194         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2195         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2196         int slot = table[i].slot;
2197         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2198       }
2199     }
2200   }
2201   if (code() != NULL) {
2202     st->print   (" - compiled code: ");
2203     code()->print_value_on(st);
2204   }
2205   if (is_native()) {
2206     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2207     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2208   }
2209 }
2210 
2211 void Method::print_linkage_flags(outputStream* st) {
2212   access_flags().print_on(st);
2213   if (is_default_method()) {
2214     st->print("default ");
2215   }
2216   if (is_overpass()) {
2217     st->print("overpass ");
2218   }
2219 }
2220 #endif //PRODUCT
2221 
2222 void Method::print_value_on(outputStream* st) const {
2223   assert(is_method(), "must be method");
2224   st->print("%s", internal_name());
2225   print_address_on(st);
2226   st->print(" ");
2227   name()->print_value_on(st);
2228   st->print(" ");
2229   signature()->print_value_on(st);
2230   st->print(" in ");
2231   method_holder()->print_value_on(st);
2232   if (WizardMode) st->print("#%d", _vtable_index);
2233   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2234   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2235 }
2236 
2237 #if INCLUDE_SERVICES
2238 // Size Statistics
2239 void Method::collect_statistics(KlassSizeStats *sz) const {
2240   int mysize = sz->count(this);
2241   sz->_method_bytes += mysize;
2242   sz->_method_all_bytes += mysize;
2243   sz->_rw_bytes += mysize;
2244 
2245   if (constMethod()) {
2246     constMethod()->collect_statistics(sz);
2247   }
2248   if (method_data()) {
2249     method_data()->collect_statistics(sz);
2250   }
2251 }
2252 #endif // INCLUDE_SERVICES
2253 
2254 // LogTouchedMethods and PrintTouchedMethods
2255 
2256 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2257 // the Method may be garbage collected. Let's roll our own hash table.
2258 class TouchedMethodRecord : CHeapObj<mtTracing> {
2259 public:
2260   // It's OK to store Symbols here because they will NOT be GC'ed if
2261   // LogTouchedMethods is enabled.
2262   TouchedMethodRecord* _next;
2263   Symbol* _class_name;
2264   Symbol* _method_name;
2265   Symbol* _method_signature;
2266 };
2267 
2268 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2269 static TouchedMethodRecord** _touched_method_table = NULL;
2270 
2271 void Method::log_touched(TRAPS) {
2272 
2273   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2274   Symbol* my_class = klass_name();
2275   Symbol* my_name  = name();
2276   Symbol* my_sig   = signature();
2277 
2278   unsigned int hash = my_class->identity_hash() +
2279                       my_name->identity_hash() +
2280                       my_sig->identity_hash();
2281   juint index = juint(hash) % table_size;
2282 
2283   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2284   if (_touched_method_table == NULL) {
2285     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2286                                               mtTracing, CURRENT_PC);
2287     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2288   }
2289 
2290   TouchedMethodRecord* ptr = _touched_method_table[index];
2291   while (ptr) {
2292     if (ptr->_class_name       == my_class &&
2293         ptr->_method_name      == my_name &&
2294         ptr->_method_signature == my_sig) {
2295       return;
2296     }
2297     if (ptr->_next == NULL) break;
2298     ptr = ptr->_next;
2299   }
2300   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2301   my_class->set_permanent();  // prevent reclaimed by GC
2302   my_name->set_permanent();
2303   my_sig->set_permanent();
2304   nptr->_class_name         = my_class;
2305   nptr->_method_name        = my_name;
2306   nptr->_method_signature   = my_sig;
2307   nptr->_next               = NULL;
2308 
2309   if (ptr == NULL) {
2310     // first
2311     _touched_method_table[index] = nptr;
2312   } else {
2313     ptr->_next = nptr;
2314   }
2315 }
2316 
2317 void Method::print_touched_methods(outputStream* out) {
2318   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2319   out->print_cr("# Method::print_touched_methods version 1");
2320   if (_touched_method_table) {
2321     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2322       TouchedMethodRecord* ptr = _touched_method_table[i];
2323       while(ptr) {
2324         ptr->_class_name->print_symbol_on(out);       out->print(".");
2325         ptr->_method_name->print_symbol_on(out);      out->print(":");
2326         ptr->_method_signature->print_symbol_on(out); out->cr();
2327         ptr = ptr->_next;
2328       }
2329     }
2330   }
2331 }
2332 
2333 // Verification
2334 
2335 void Method::verify_on(outputStream* st) {
2336   guarantee(is_method(), "object must be method");
2337   guarantee(constants()->is_constantPool(), "should be constant pool");
2338   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2339   MethodData* md = method_data();
2340   guarantee(md == NULL ||
2341       md->is_methodData(), "should be method data");
2342 }