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/debugInfoRec.hpp"
  29 #include "gc_interface/collectedHeap.inline.hpp"
  30 #include "interpreter/bytecodeStream.hpp"
  31 #include "interpreter/bytecodeTracer.hpp"
  32 #include "interpreter/bytecodes.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "memory/gcLocker.hpp"
  36 #include "memory/generation.hpp"
  37 #include "memory/heapInspection.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/oopFactory.hpp"
  40 #include "oops/constMethod.hpp"
  41 #include "oops/methodData.hpp"
  42 #include "oops/method.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "oops/symbol.hpp"
  45 #include "prims/jvmtiExport.hpp"
  46 #include "prims/methodHandles.hpp"
  47 #include "prims/nativeLookup.hpp"
  48 #include "runtime/arguments.hpp"
  49 #include "runtime/compilationPolicy.hpp"
  50 #include "runtime/frame.inline.hpp"
  51 #include "runtime/handles.inline.hpp"
  52 #include "runtime/orderAccess.inline.hpp"
  53 #include "runtime/relocator.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "utilities/quickSort.hpp"
  57 #include "utilities/xmlstream.hpp"
  58 
  59 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  60 
  61 // Implementation of Method
  62 
  63 Method* Method::allocate(ClassLoaderData* loader_data,
  64                          int byte_code_size,
  65                          AccessFlags access_flags,
  66                          InlineTableSizes* sizes,
  67                          ConstMethod::MethodType method_type,
  68                          TRAPS) {
  69   assert(!access_flags.is_native() || byte_code_size == 0,
  70          "native methods should not contain byte codes");
  71   ConstMethod* cm = ConstMethod::allocate(loader_data,
  72                                           byte_code_size,
  73                                           sizes,
  74                                           method_type,
  75                                           CHECK_NULL);
  76 
  77   int size = Method::size(access_flags.is_native());
  78 
  79   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
  80 }
  81 
  82 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
  83   No_Safepoint_Verifier no_safepoint;
  84   set_constMethod(xconst);
  85   set_access_flags(access_flags);
  86   set_method_size(size);
  87   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   clear_jmethod_id(loader_data);
 114   MetadataFactory::free_metadata(loader_data, constMethod());
 115   set_constMethod(NULL);
 116   MetadataFactory::free_metadata(loader_data, method_data());
 117   set_method_data(NULL);
 118   MetadataFactory::free_metadata(loader_data, method_counters());
 119   clear_method_counters();
 120   // The nmethod will be gone when we get here.
 121   if (code() != NULL) _code = NULL;
 122 }
 123 
 124 address Method::get_i2c_entry() {
 125   assert(_adapter != NULL, "must have");
 126   return _adapter->get_i2c_entry();
 127 }
 128 
 129 address Method::get_c2i_entry() {
 130   assert(_adapter != NULL, "must have");
 131   return _adapter->get_c2i_entry();
 132 }
 133 
 134 address Method::get_c2i_unverified_entry() {
 135   assert(_adapter != NULL, "must have");
 136   return _adapter->get_c2i_unverified_entry();
 137 }
 138 
 139 char* Method::name_and_sig_as_C_string() const {
 140   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 141 }
 142 
 143 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 144   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 145 }
 146 
 147 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 148   const char* klass_name = klass->external_name();
 149   int klass_name_len  = (int)strlen(klass_name);
 150   int method_name_len = method_name->utf8_length();
 151   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 152   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 153   strcpy(dest, klass_name);
 154   dest[klass_name_len] = '.';
 155   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 156   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 157   dest[len] = 0;
 158   return dest;
 159 }
 160 
 161 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 162   Symbol* klass_name = klass->name();
 163   klass_name->as_klass_external_name(buf, size);
 164   int len = (int)strlen(buf);
 165 
 166   if (len < size - 1) {
 167     buf[len++] = '.';
 168 
 169     method_name->as_C_string(&(buf[len]), size - len);
 170     len = (int)strlen(buf);
 171 
 172     signature->as_C_string(&(buf[len]), size - len);
 173   }
 174 
 175   return buf;
 176 }
 177 
 178 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 179   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 180   // access exception table
 181   ExceptionTable table(mh());
 182   int length = table.length();
 183   // iterate through all entries sequentially
 184   constantPoolHandle pool(THREAD, mh->constants());
 185   for (int i = 0; i < length; i ++) {
 186     //reacquire the table in case a GC happened
 187     ExceptionTable table(mh());
 188     int beg_bci = table.start_pc(i);
 189     int end_bci = table.end_pc(i);
 190     assert(beg_bci <= end_bci, "inconsistent exception table");
 191     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 192       // exception handler bci range covers throw_bci => investigate further
 193       int handler_bci = table.handler_pc(i);
 194       int klass_index = table.catch_type_index(i);
 195       if (klass_index == 0) {
 196         return handler_bci;
 197       } else if (ex_klass.is_null()) {
 198         return handler_bci;
 199       } else {
 200         // we know the exception class => get the constraint class
 201         // this may require loading of the constraint class; if verification
 202         // fails or some other exception occurs, return handler_bci
 203         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 204         KlassHandle klass = KlassHandle(THREAD, k);
 205         assert(klass.not_null(), "klass not loaded");
 206         if (ex_klass->is_subtype_of(klass())) {
 207           return handler_bci;
 208         }
 209       }
 210     }
 211   }
 212 
 213   return -1;
 214 }
 215 
 216 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 217 
 218   Thread* myThread    = Thread::current();
 219   methodHandle h_this(myThread, this);
 220 #ifdef ASSERT
 221   bool has_capability = myThread->is_VM_thread() ||
 222                         myThread->is_ConcurrentGC_thread() ||
 223                         myThread->is_GC_task_thread();
 224 
 225   if (!has_capability) {
 226     if (!VerifyStack && !VerifyLastFrame) {
 227       // verify stack calls this outside VM thread
 228       warning("oopmap should only be accessed by the "
 229               "VM, GC task or CMS threads (or during debugging)");
 230       InterpreterOopMap local_mask;
 231       method_holder()->mask_for(h_this, bci, &local_mask);
 232       local_mask.print();
 233     }
 234   }
 235 #endif
 236   method_holder()->mask_for(h_this, bci, mask);
 237   return;
 238 }
 239 
 240 
 241 int Method::bci_from(address bcp) const {
 242 #ifdef ASSERT
 243   { ResourceMark rm;
 244   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 245          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
 246   }
 247 #endif
 248   return bcp - code_base();
 249 }
 250 
 251 
 252 // Return (int)bcx if it appears to be a valid BCI.
 253 // Return bci_from((address)bcx) if it appears to be a valid BCP.
 254 // Return -1 otherwise.
 255 // Used by profiling code, when invalid data is a possibility.
 256 // The caller is responsible for validating the Method* itself.
 257 int Method::validate_bci_from_bcx(intptr_t bcx) const {
 258   // keep bci as -1 if not a valid bci
 259   int bci = -1;
 260   if (bcx == 0 || (address)bcx == code_base()) {
 261     // code_size() may return 0 and we allow 0 here
 262     // the method may be native
 263     bci = 0;
 264   } else if (frame::is_bci(bcx)) {
 265     if (bcx < code_size()) {
 266       bci = (int)bcx;
 267     }
 268   } else if (contains((address)bcx)) {
 269     bci = (address)bcx - code_base();
 270   }
 271   // Assert that if we have dodged any asserts, bci is negative.
 272   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 273   return bci;
 274 }
 275 
 276 address Method::bcp_from(int bci) const {
 277   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), err_msg("illegal bci: %d", bci));
 278   address bcp = code_base() + bci;
 279   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 280   return bcp;
 281 }
 282 
 283 
 284 int Method::size(bool is_native) {
 285   // If native, then include pointers for native_function and signature_handler
 286   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 287   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 288   return align_object_size(header_size() + extra_words);
 289 }
 290 
 291 
 292 Symbol* Method::klass_name() const {
 293   Klass* k = method_holder();
 294   assert(k->is_klass(), "must be klass");
 295   InstanceKlass* ik = (InstanceKlass*) k;
 296   return ik->name();
 297 }
 298 
 299 
 300 // Attempt to return method oop to original state.  Clear any pointers
 301 // (to objects outside the shared spaces).  We won't be able to predict
 302 // where they should point in a new JVM.  Further initialize some
 303 // entries now in order allow them to be write protected later.
 304 
 305 void Method::remove_unshareable_info() {
 306   unlink_method();
 307 }
 308 
 309 
 310 bool Method::was_executed_more_than(int n) {
 311   // Invocation counter is reset when the Method* is compiled.
 312   // If the method has compiled code we therefore assume it has
 313   // be excuted more than n times.
 314   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 315     // interpreter doesn't bump invocation counter of trivial methods
 316     // compiler does not bump invocation counter of compiled methods
 317     return true;
 318   }
 319   else if ((method_counters() != NULL &&
 320             method_counters()->invocation_counter()->carry()) ||
 321            (method_data() != NULL &&
 322             method_data()->invocation_counter()->carry())) {
 323     // The carry bit is set when the counter overflows and causes
 324     // a compilation to occur.  We don't know how many times
 325     // the counter has been reset, so we simply assume it has
 326     // been executed more than n times.
 327     return true;
 328   } else {
 329     return invocation_count() > n;
 330   }
 331 }
 332 
 333 #ifndef PRODUCT
 334 void Method::print_invocation_count() {
 335   if (is_static()) tty->print("static ");
 336   if (is_final()) tty->print("final ");
 337   if (is_synchronized()) tty->print("synchronized ");
 338   if (is_native()) tty->print("native ");
 339   method_holder()->name()->print_symbol_on(tty);
 340   tty->print(".");
 341   name()->print_symbol_on(tty);
 342   signature()->print_symbol_on(tty);
 343 
 344   if (WizardMode) {
 345     // dump the size of the byte codes
 346     tty->print(" {%d}", code_size());
 347   }
 348   tty->cr();
 349 
 350   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 351   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 352   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 353   if (CountCompiledCalls) {
 354     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 355   }
 356 
 357 }
 358 #endif
 359 
 360 // Build a MethodData* object to hold information about this method
 361 // collected in the interpreter.
 362 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
 363   // Do not profile method if current thread holds the pending list lock,
 364   // which avoids deadlock for acquiring the MethodData_lock.
 365   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
 366     return;
 367   }
 368 
 369   // Grab a lock here to prevent multiple
 370   // MethodData*s from being created.
 371   MutexLocker ml(MethodData_lock, THREAD);
 372   if (method->method_data() == NULL) {
 373     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 374     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
 375     method->set_method_data(method_data);
 376     if (PrintMethodData && (Verbose || WizardMode)) {
 377       ResourceMark rm(THREAD);
 378       tty->print("build_interpreter_method_data for ");
 379       method->print_name(tty);
 380       tty->cr();
 381       // At the end of the run, the MDO, full of data, will be dumped.
 382     }
 383   }
 384 }
 385 
 386 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 387   methodHandle mh(m);
 388   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
 389   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
 390   if (!mh->init_method_counters(counters)) {
 391     MetadataFactory::free_metadata(loader_data, counters);
 392   }
 393   return mh->method_counters();
 394 }
 395 
 396 void Method::cleanup_inline_caches() {
 397   // The current system doesn't use inline caches in the interpreter
 398   // => nothing to do (keep this method around for future use)
 399 }
 400 
 401 
 402 int Method::extra_stack_words() {
 403   // not an inline function, to avoid a header dependency on Interpreter
 404   return extra_stack_entries() * Interpreter::stackElementSize;
 405 }
 406 
 407 
 408 void Method::compute_size_of_parameters(Thread *thread) {
 409   ArgumentSizeComputer asc(signature());
 410   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 411 }
 412 
 413 BasicType Method::result_type() const {
 414   ResultTypeFinder rtf(signature());
 415   return rtf.type();
 416 }
 417 
 418 
 419 bool Method::is_empty_method() const {
 420   return  code_size() == 1
 421       && *code_base() == Bytecodes::_return;
 422 }
 423 
 424 
 425 bool Method::is_vanilla_constructor() const {
 426   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 427   // which only calls the superclass vanilla constructor and possibly does stores of
 428   // zero constants to local fields:
 429   //
 430   //   aload_0
 431   //   invokespecial
 432   //   indexbyte1
 433   //   indexbyte2
 434   //
 435   // followed by an (optional) sequence of:
 436   //
 437   //   aload_0
 438   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 439   //   putfield
 440   //   indexbyte1
 441   //   indexbyte2
 442   //
 443   // followed by:
 444   //
 445   //   return
 446 
 447   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 448   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 449   int size = code_size();
 450   // Check if size match
 451   if (size == 0 || size % 5 != 0) return false;
 452   address cb = code_base();
 453   int last = size - 1;
 454   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 455     // Does not call superclass default constructor
 456     return false;
 457   }
 458   // Check optional sequence
 459   for (int i = 4; i < last; i += 5) {
 460     if (cb[i] != Bytecodes::_aload_0) return false;
 461     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 462     if (cb[i+2] != Bytecodes::_putfield) return false;
 463   }
 464   return true;
 465 }
 466 
 467 
 468 bool Method::compute_has_loops_flag() {
 469   BytecodeStream bcs(this);
 470   Bytecodes::Code bc;
 471 
 472   while ((bc = bcs.next()) >= 0) {
 473     switch( bc ) {
 474       case Bytecodes::_ifeq:
 475       case Bytecodes::_ifnull:
 476       case Bytecodes::_iflt:
 477       case Bytecodes::_ifle:
 478       case Bytecodes::_ifne:
 479       case Bytecodes::_ifnonnull:
 480       case Bytecodes::_ifgt:
 481       case Bytecodes::_ifge:
 482       case Bytecodes::_if_icmpeq:
 483       case Bytecodes::_if_icmpne:
 484       case Bytecodes::_if_icmplt:
 485       case Bytecodes::_if_icmpgt:
 486       case Bytecodes::_if_icmple:
 487       case Bytecodes::_if_icmpge:
 488       case Bytecodes::_if_acmpeq:
 489       case Bytecodes::_if_acmpne:
 490       case Bytecodes::_goto:
 491       case Bytecodes::_jsr:
 492         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 493         break;
 494 
 495       case Bytecodes::_goto_w:
 496       case Bytecodes::_jsr_w:
 497         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 498         break;
 499     }
 500   }
 501   _access_flags.set_loops_flag_init();
 502   return _access_flags.has_loops();
 503 }
 504 
 505 bool Method::is_final_method(AccessFlags class_access_flags) const {
 506   // or "does_not_require_vtable_entry"
 507   // default method or overpass can occur, is not final (reuses vtable entry)
 508   // private methods get vtable entries for backward class compatibility.
 509   if (is_overpass() || is_default_method())  return false;
 510   return is_final() || class_access_flags.is_final();
 511 }
 512 
 513 bool Method::is_final_method() const {
 514   return is_final_method(method_holder()->access_flags());
 515 }
 516 
 517 bool Method::is_default_method() const {
 518   if (method_holder() != NULL &&
 519       method_holder()->is_interface() &&
 520       !is_abstract()) {
 521     return true;
 522   } else {
 523     return false;
 524   }
 525 }
 526 
 527 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 528   if (is_final_method(class_access_flags))  return true;
 529 #ifdef ASSERT
 530   ResourceMark rm;
 531   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 532   if (class_access_flags.is_interface()) {
 533       assert(is_nonv == is_static(), err_msg("is_nonv=%s", name_and_sig_as_C_string()));
 534   }
 535 #endif
 536   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 537   return vtable_index() == nonvirtual_vtable_index;
 538 }
 539 
 540 bool Method::can_be_statically_bound() const {
 541   return can_be_statically_bound(method_holder()->access_flags());
 542 }
 543 
 544 bool Method::is_accessor() const {
 545   if (code_size() != 5) return false;
 546   if (size_of_parameters() != 1) return false;
 547   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
 548   if (java_code_at(1) != Bytecodes::_getfield) return false;
 549   if (java_code_at(4) != Bytecodes::_areturn &&
 550       java_code_at(4) != Bytecodes::_ireturn ) return false;
 551   return true;
 552 }
 553 
 554 bool Method::is_constant_getter() const {
 555   int last_index = code_size() - 1;
 556   // Check if the first 1-3 bytecodes are a constant push
 557   // and the last bytecode is a return.
 558   return (2 <= code_size() && code_size() <= 4 &&
 559           Bytecodes::is_const(java_code_at(0)) &&
 560           Bytecodes::length_for(java_code_at(0)) == last_index &&
 561           Bytecodes::is_return(java_code_at(last_index)));
 562 }
 563 
 564 bool Method::is_initializer() const {
 565   return name() == vmSymbols::object_initializer_name() || is_static_initializer();
 566 }
 567 
 568 bool Method::has_valid_initializer_flags() const {
 569   return (is_static() ||
 570           method_holder()->major_version() < 51);
 571 }
 572 
 573 bool Method::is_static_initializer() const {
 574   // For classfiles version 51 or greater, ensure that the clinit method is
 575   // static.  Non-static methods with the name "<clinit>" are not static
 576   // initializers. (older classfiles exempted for backward compatibility)
 577   return name() == vmSymbols::class_initializer_name() &&
 578          has_valid_initializer_flags();
 579 }
 580 
 581 
 582 objArrayHandle Method::resolved_checked_exceptions_impl(Method* this_oop, TRAPS) {
 583   int length = this_oop->checked_exceptions_length();
 584   if (length == 0) {  // common case
 585     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 586   } else {
 587     methodHandle h_this(THREAD, this_oop);
 588     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 589     objArrayHandle mirrors (THREAD, m_oop);
 590     for (int i = 0; i < length; i++) {
 591       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 592       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 593       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 594       mirrors->obj_at_put(i, k->java_mirror());
 595     }
 596     return mirrors;
 597   }
 598 };
 599 
 600 
 601 int Method::line_number_from_bci(int bci) const {
 602   if (bci == SynchronizationEntryBCI) bci = 0;
 603   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 604   int best_bci  =  0;
 605   int best_line = -1;
 606 
 607   if (has_linenumber_table()) {
 608     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 609     // Not necessarily sorted and not necessarily one-to-one.
 610     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 611     while (stream.read_pair()) {
 612       if (stream.bci() == bci) {
 613         // perfect match
 614         return stream.line();
 615       } else {
 616         // update best_bci/line
 617         if (stream.bci() < bci && stream.bci() >= best_bci) {
 618           best_bci  = stream.bci();
 619           best_line = stream.line();
 620         }
 621       }
 622     }
 623   }
 624   return best_line;
 625 }
 626 
 627 
 628 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 629   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 630     Thread *thread = Thread::current();
 631     Symbol* klass_name = constants()->klass_name_at(klass_index);
 632     Handle loader(thread, method_holder()->class_loader());
 633     Handle prot  (thread, method_holder()->protection_domain());
 634     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 635   } else {
 636     return true;
 637   }
 638 }
 639 
 640 
 641 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 642   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 643   if (must_be_resolved) {
 644     // Make sure klass is resolved in constantpool.
 645     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 646   }
 647   return is_klass_loaded_by_klass_index(klass_index);
 648 }
 649 
 650 
 651 void Method::set_native_function(address function, bool post_event_flag) {
 652   assert(function != NULL, "use clear_native_function to unregister natives");
 653   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 654   address* native_function = native_function_addr();
 655 
 656   // We can see racers trying to place the same native function into place. Once
 657   // is plenty.
 658   address current = *native_function;
 659   if (current == function) return;
 660   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 661       function != NULL) {
 662     // native_method_throw_unsatisfied_link_error_entry() should only
 663     // be passed when post_event_flag is false.
 664     assert(function !=
 665       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 666       "post_event_flag mis-match");
 667 
 668     // post the bind event, and possible change the bind function
 669     JvmtiExport::post_native_method_bind(this, &function);
 670   }
 671   *native_function = function;
 672   // This function can be called more than once. We must make sure that we always
 673   // use the latest registered method -> check if a stub already has been generated.
 674   // If so, we have to make it not_entrant.
 675   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
 676   if (nm != NULL) {
 677     nm->make_not_entrant();
 678   }
 679 }
 680 
 681 
 682 bool Method::has_native_function() const {
 683   if (is_method_handle_intrinsic())
 684     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 685   address func = native_function();
 686   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 687 }
 688 
 689 
 690 void Method::clear_native_function() {
 691   // Note: is_method_handle_intrinsic() is allowed here.
 692   set_native_function(
 693     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 694     !native_bind_event_is_interesting);
 695   clear_code();
 696 }
 697 
 698 address Method::critical_native_function() {
 699   methodHandle mh(this);
 700   return NativeLookup::lookup_critical_entry(mh);
 701 }
 702 
 703 
 704 void Method::set_signature_handler(address handler) {
 705   address* signature_handler =  signature_handler_addr();
 706   *signature_handler = handler;
 707 }
 708 
 709 
 710 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 711   if (PrintCompilation && report) {
 712     ttyLocker ttyl;
 713     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 714     if (comp_level == CompLevel_all) {
 715       tty->print("all levels ");
 716     } else {
 717       tty->print("levels ");
 718       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 719         tty->print("%d ", i);
 720       }
 721     }
 722     this->print_short_name(tty);
 723     int size = this->code_size();
 724     if (size > 0) {
 725       tty->print(" (%d bytes)", size);
 726     }
 727     if (reason != NULL) {
 728       tty->print("   %s", reason);
 729     }
 730     tty->cr();
 731   }
 732   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 733     ttyLocker ttyl;
 734     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 735                      os::current_thread_id(), is_osr, comp_level);
 736     if (reason != NULL) {
 737       xtty->print(" reason=\'%s\'", reason);
 738     }
 739     xtty->method(this);
 740     xtty->stamp();
 741     xtty->end_elem();
 742   }
 743 }
 744 
 745 bool Method::is_always_compilable() const {
 746   // Generated adapters must be compiled
 747   if (is_method_handle_intrinsic() && is_synthetic()) {
 748     assert(!is_not_c1_compilable(), "sanity check");
 749     assert(!is_not_c2_compilable(), "sanity check");
 750     return true;
 751   }
 752 
 753   return false;
 754 }
 755 
 756 bool Method::is_not_compilable(int comp_level) const {
 757   if (number_of_breakpoints() > 0)
 758     return true;
 759   if (is_always_compilable())
 760     return false;
 761   if (comp_level == CompLevel_any)
 762     return is_not_c1_compilable() || is_not_c2_compilable();
 763   if (is_c1_compile(comp_level))
 764     return is_not_c1_compilable();
 765   if (is_c2_compile(comp_level))
 766     return is_not_c2_compilable();
 767   return false;
 768 }
 769 
 770 // call this when compiler finds that this method is not compilable
 771 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 772   if (is_always_compilable()) {
 773     // Don't mark a method which should be always compilable
 774     return;
 775   }
 776   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 777   if (comp_level == CompLevel_all) {
 778     set_not_c1_compilable();
 779     set_not_c2_compilable();
 780   } else {
 781     if (is_c1_compile(comp_level))
 782       set_not_c1_compilable();
 783     if (is_c2_compile(comp_level))
 784       set_not_c2_compilable();
 785   }
 786   CompilationPolicy::policy()->disable_compilation(this);
 787   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 788 }
 789 
 790 bool Method::is_not_osr_compilable(int comp_level) const {
 791   if (is_not_compilable(comp_level))
 792     return true;
 793   if (comp_level == CompLevel_any)
 794     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 795   if (is_c1_compile(comp_level))
 796     return is_not_c1_osr_compilable();
 797   if (is_c2_compile(comp_level))
 798     return is_not_c2_osr_compilable();
 799   return false;
 800 }
 801 
 802 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 803   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 804   if (comp_level == CompLevel_all) {
 805     set_not_c1_osr_compilable();
 806     set_not_c2_osr_compilable();
 807   } else {
 808     if (is_c1_compile(comp_level))
 809       set_not_c1_osr_compilable();
 810     if (is_c2_compile(comp_level))
 811       set_not_c2_osr_compilable();
 812   }
 813   CompilationPolicy::policy()->disable_compilation(this);
 814   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 815 }
 816 
 817 // Revert to using the interpreter and clear out the nmethod
 818 void Method::clear_code() {
 819 
 820   // this may be NULL if c2i adapters have not been made yet
 821   // Only should happen at allocate time.
 822   if (_adapter == NULL) {
 823     _from_compiled_entry    = NULL;
 824   } else {
 825     _from_compiled_entry    = _adapter->get_c2i_entry();
 826   }
 827   OrderAccess::storestore();
 828   _from_interpreted_entry = _i2i_entry;
 829   OrderAccess::storestore();
 830   _code = NULL;
 831 }
 832 
 833 // Called by class data sharing to remove any entry points (which are not shared)
 834 void Method::unlink_method() {
 835   _code = NULL;
 836   _i2i_entry = NULL;
 837   _from_interpreted_entry = NULL;
 838   if (is_native()) {
 839     *native_function_addr() = NULL;
 840     set_signature_handler(NULL);
 841   }
 842   NOT_PRODUCT(set_compiled_invocation_count(0);)
 843   _adapter = NULL;
 844   _from_compiled_entry = NULL;
 845 
 846   // In case of DumpSharedSpaces, _method_data should always be NULL.
 847   //
 848   // During runtime (!DumpSharedSpaces), when we are cleaning a
 849   // shared class that failed to load, this->link_method() may
 850   // have already been called (before an exception happened), so
 851   // this->_method_data may not be NULL.
 852   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
 853 
 854   set_method_data(NULL);
 855   clear_method_counters();
 856 }
 857 
 858 // Called when the method_holder is getting linked. Setup entrypoints so the method
 859 // is ready to be called from interpreter, compiler, and vtables.
 860 void Method::link_method(methodHandle h_method, TRAPS) {
 861   // If the code cache is full, we may reenter this function for the
 862   // leftover methods that weren't linked.
 863   if (_i2i_entry != NULL) return;
 864 
 865   assert(_adapter == NULL, "init'd to NULL" );
 866   assert( _code == NULL, "nothing compiled yet" );
 867 
 868   // Setup interpreter entrypoint
 869   assert(this == h_method(), "wrong h_method()" );
 870   address entry = Interpreter::entry_for_method(h_method);
 871   assert(entry != NULL, "interpreter entry must be non-null");
 872   // Sets both _i2i_entry and _from_interpreted_entry
 873   set_interpreter_entry(entry);
 874 
 875   // Don't overwrite already registered native entries.
 876   if (is_native() && !has_native_function()) {
 877     set_native_function(
 878       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 879       !native_bind_event_is_interesting);
 880   }
 881 
 882   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 883   // special handling of vtables.  An alternative is to make adapters more
 884   // lazily by calling make_adapter() from from_compiled_entry() for the
 885   // normal calls.  For vtable calls life gets more complicated.  When a
 886   // call-site goes mega-morphic we need adapters in all methods which can be
 887   // called from the vtable.  We need adapters on such methods that get loaded
 888   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 889   // problem we'll make these lazily later.
 890   (void) make_adapters(h_method, CHECK);
 891 
 892   // ONLY USE the h_method now as make_adapter may have blocked
 893 
 894 }
 895 
 896 address Method::make_adapters(methodHandle mh, TRAPS) {
 897   // Adapters for compiled code are made eagerly here.  They are fairly
 898   // small (generally < 100 bytes) and quick to make (and cached and shared)
 899   // so making them eagerly shouldn't be too expensive.
 900   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
 901   if (adapter == NULL ) {
 902     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
 903   }
 904 
 905   mh->set_adapter_entry(adapter);
 906   mh->_from_compiled_entry = adapter->get_c2i_entry();
 907   return adapter->get_c2i_entry();
 908 }
 909 
 910 void Method::restore_unshareable_info(TRAPS) {
 911   // Since restore_unshareable_info can be called more than once for a method, don't
 912   // redo any work.   If this field is restored, there is nothing to do.
 913   if (_from_compiled_entry == NULL) {
 914     // restore method's vtable by calling a virtual function
 915     restore_vtable();
 916 
 917     methodHandle mh(THREAD, this);
 918     link_method(mh, CHECK);
 919   }
 920 }
 921 
 922 
 923 // The verified_code_entry() must be called when a invoke is resolved
 924 // on this method.
 925 
 926 // It returns the compiled code entry point, after asserting not null.
 927 // This function is called after potential safepoints so that nmethod
 928 // or adapter that it points to is still live and valid.
 929 // This function must not hit a safepoint!
 930 address Method::verified_code_entry() {
 931   debug_only(No_Safepoint_Verifier nsv;)
 932   assert(_from_compiled_entry != NULL, "must be set");
 933   return _from_compiled_entry;
 934 }
 935 
 936 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
 937 // (could be racing a deopt).
 938 // Not inline to avoid circular ref.
 939 bool Method::check_code() const {
 940   // cached in a register or local.  There's a race on the value of the field.
 941   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
 942   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
 943 }
 944 
 945 // Install compiled code.  Instantly it can execute.
 946 void Method::set_code(methodHandle mh, nmethod *code) {
 947   assert( code, "use clear_code to remove code" );
 948   assert( mh->check_code(), "" );
 949 
 950   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
 951 
 952   // These writes must happen in this order, because the interpreter will
 953   // directly jump to from_interpreted_entry which jumps to an i2c adapter
 954   // which jumps to _from_compiled_entry.
 955   mh->_code = code;             // Assign before allowing compiled code to exec
 956 
 957   int comp_level = code->comp_level();
 958   // In theory there could be a race here. In practice it is unlikely
 959   // and not worth worrying about.
 960   if (comp_level > mh->highest_comp_level()) {
 961     mh->set_highest_comp_level(comp_level);
 962   }
 963 
 964   OrderAccess::storestore();
 965 #ifdef SHARK
 966   mh->_from_interpreted_entry = code->insts_begin();
 967 #else //!SHARK
 968   mh->_from_compiled_entry = code->verified_entry_point();
 969   OrderAccess::storestore();
 970   // Instantly compiled code can execute.
 971   if (!mh->is_method_handle_intrinsic())
 972     mh->_from_interpreted_entry = mh->get_i2c_entry();
 973 #endif //!SHARK
 974 }
 975 
 976 
 977 bool Method::is_overridden_in(Klass* k) const {
 978   InstanceKlass* ik = InstanceKlass::cast(k);
 979 
 980   if (ik->is_interface()) return false;
 981 
 982   // If method is an interface, we skip it - except if it
 983   // is a miranda method
 984   if (method_holder()->is_interface()) {
 985     // Check that method is not a miranda method
 986     if (ik->lookup_method(name(), signature()) == NULL) {
 987       // No implementation exist - so miranda method
 988       return false;
 989     }
 990     return true;
 991   }
 992 
 993   assert(ik->is_subclass_of(method_holder()), "should be subklass");
 994   assert(ik->vtable() != NULL, "vtable should exist");
 995   if (!has_vtable_index()) {
 996     return false;
 997   } else {
 998     Method* vt_m = ik->method_at_vtable(vtable_index());
 999     return vt_m != this;
1000   }
1001 }
1002 
1003 
1004 // give advice about whether this Method* should be cached or not
1005 bool Method::should_not_be_cached() const {
1006   if (is_old()) {
1007     // This method has been redefined. It is either EMCP or obsolete
1008     // and we don't want to cache it because that would pin the method
1009     // down and prevent it from being collectible if and when it
1010     // finishes executing.
1011     return true;
1012   }
1013 
1014   // caching this method should be just fine
1015   return false;
1016 }
1017 
1018 
1019 /**
1020  *  Returns true if this is one of the specially treated methods for
1021  *  security related stack walks (like Reflection.getCallerClass).
1022  */
1023 bool Method::is_ignored_by_security_stack_walk() const {
1024   const bool use_new_reflection = JDK_Version::is_gte_jdk14x_version() && UseNewReflection;
1025 
1026   if (intrinsic_id() == vmIntrinsics::_invoke) {
1027     // This is Method.invoke() -- ignore it
1028     return true;
1029   }
1030   if (use_new_reflection &&
1031       method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1032     // This is an auxilary frame -- ignore it
1033     return true;
1034   }
1035   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1036     // This is an internal adapter frame for method handles -- ignore it
1037     return true;
1038   }
1039   return false;
1040 }
1041 
1042 
1043 // Constant pool structure for invoke methods:
1044 enum {
1045   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1046   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1047   _imcp_limit
1048 };
1049 
1050 // Test if this method is an MH adapter frame generated by Java code.
1051 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1052 bool Method::is_compiled_lambda_form() const {
1053   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1054 }
1055 
1056 // Test if this method is an internal MH primitive method.
1057 bool Method::is_method_handle_intrinsic() const {
1058   vmIntrinsics::ID iid = intrinsic_id();
1059   return (MethodHandles::is_signature_polymorphic(iid) &&
1060           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1061 }
1062 
1063 bool Method::has_member_arg() const {
1064   vmIntrinsics::ID iid = intrinsic_id();
1065   return (MethodHandles::is_signature_polymorphic(iid) &&
1066           MethodHandles::has_member_arg(iid));
1067 }
1068 
1069 // Make an instance of a signature-polymorphic internal MH primitive.
1070 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1071                                                          Symbol* signature,
1072                                                          TRAPS) {
1073   ResourceMark rm;
1074   methodHandle empty;
1075 
1076   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1077   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1078   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1079   if (TraceMethodHandles) {
1080     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1081   }
1082 
1083   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1084   name->increment_refcount();
1085   signature->increment_refcount();
1086 
1087   int cp_length = _imcp_limit;
1088   ClassLoaderData* loader_data = holder->class_loader_data();
1089   constantPoolHandle cp;
1090   {
1091     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1092     cp = constantPoolHandle(THREAD, cp_oop);
1093   }
1094   cp->set_pool_holder(InstanceKlass::cast(holder()));
1095   cp->symbol_at_put(_imcp_invoke_name,       name);
1096   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1097   cp->set_has_preresolution();
1098 
1099   // decide on access bits:  public or not?
1100   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1101   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1102   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1103   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1104 
1105   methodHandle m;
1106   {
1107     InlineTableSizes sizes;
1108     Method* m_oop = Method::allocate(loader_data, 0,
1109                                      accessFlags_from(flags_bits), &sizes,
1110                                      ConstMethod::NORMAL, CHECK_(empty));
1111     m = methodHandle(THREAD, m_oop);
1112   }
1113   m->set_constants(cp());
1114   m->set_name_index(_imcp_invoke_name);
1115   m->set_signature_index(_imcp_invoke_signature);
1116   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1117   assert(m->signature() == signature, "");
1118   ResultTypeFinder rtf(signature);
1119   m->constMethod()->set_result_type(rtf.type());
1120   m->compute_size_of_parameters(THREAD);
1121   m->init_intrinsic_id();
1122   assert(m->is_method_handle_intrinsic(), "");
1123 #ifdef ASSERT
1124   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1125   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1126   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1127 #endif //ASSERT
1128 
1129   // Finally, set up its entry points.
1130   assert(m->can_be_statically_bound(), "");
1131   m->set_vtable_index(Method::nonvirtual_vtable_index);
1132   m->link_method(m, CHECK_(empty));
1133 
1134   if (TraceMethodHandles && (Verbose || WizardMode))
1135     m->print_on(tty);
1136 
1137   return m;
1138 }
1139 
1140 Klass* Method::check_non_bcp_klass(Klass* klass) {
1141   if (klass != NULL && klass->class_loader() != NULL) {
1142     if (klass->oop_is_objArray())
1143       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1144     return klass;
1145   }
1146   return NULL;
1147 }
1148 
1149 
1150 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1151                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1152   // Code below does not work for native methods - they should never get rewritten anyway
1153   assert(!m->is_native(), "cannot rewrite native methods");
1154   // Allocate new Method*
1155   AccessFlags flags = m->access_flags();
1156 
1157   ConstMethod* cm = m->constMethod();
1158   int checked_exceptions_len = cm->checked_exceptions_length();
1159   int localvariable_len = cm->localvariable_table_length();
1160   int exception_table_len = cm->exception_table_length();
1161   int method_parameters_len = cm->method_parameters_length();
1162   int method_annotations_len = cm->method_annotations_length();
1163   int parameter_annotations_len = cm->parameter_annotations_length();
1164   int type_annotations_len = cm->type_annotations_length();
1165   int default_annotations_len = cm->default_annotations_length();
1166 
1167   InlineTableSizes sizes(
1168       localvariable_len,
1169       new_compressed_linenumber_size,
1170       exception_table_len,
1171       checked_exceptions_len,
1172       method_parameters_len,
1173       cm->generic_signature_index(),
1174       method_annotations_len,
1175       parameter_annotations_len,
1176       type_annotations_len,
1177       default_annotations_len,
1178       0);
1179 
1180   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1181   Method* newm_oop = Method::allocate(loader_data,
1182                                       new_code_length,
1183                                       flags,
1184                                       &sizes,
1185                                       m->method_type(),
1186                                       CHECK_(methodHandle()));
1187   methodHandle newm (THREAD, newm_oop);
1188   int new_method_size = newm->method_size();
1189 
1190   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1191   ConstMethod* newcm = newm->constMethod();
1192   int new_const_method_size = newm->constMethod()->size();
1193 
1194   memcpy(newm(), m(), sizeof(Method));
1195 
1196   // Create shallow copy of ConstMethod.
1197   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1198 
1199   // Reset correct method/const method, method size, and parameter info
1200   newm->set_constMethod(newcm);
1201   newm->constMethod()->set_code_size(new_code_length);
1202   newm->constMethod()->set_constMethod_size(new_const_method_size);
1203   newm->set_method_size(new_method_size);
1204   assert(newm->code_size() == new_code_length, "check");
1205   assert(newm->method_parameters_length() == method_parameters_len, "check");
1206   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1207   assert(newm->exception_table_length() == exception_table_len, "check");
1208   assert(newm->localvariable_table_length() == localvariable_len, "check");
1209   // Copy new byte codes
1210   memcpy(newm->code_base(), new_code, new_code_length);
1211   // Copy line number table
1212   if (new_compressed_linenumber_size > 0) {
1213     memcpy(newm->compressed_linenumber_table(),
1214            new_compressed_linenumber_table,
1215            new_compressed_linenumber_size);
1216   }
1217   // Copy method_parameters
1218   if (method_parameters_len > 0) {
1219     memcpy(newm->method_parameters_start(),
1220            m->method_parameters_start(),
1221            method_parameters_len * sizeof(MethodParametersElement));
1222   }
1223   // Copy checked_exceptions
1224   if (checked_exceptions_len > 0) {
1225     memcpy(newm->checked_exceptions_start(),
1226            m->checked_exceptions_start(),
1227            checked_exceptions_len * sizeof(CheckedExceptionElement));
1228   }
1229   // Copy exception table
1230   if (exception_table_len > 0) {
1231     memcpy(newm->exception_table_start(),
1232            m->exception_table_start(),
1233            exception_table_len * sizeof(ExceptionTableElement));
1234   }
1235   // Copy local variable number table
1236   if (localvariable_len > 0) {
1237     memcpy(newm->localvariable_table_start(),
1238            m->localvariable_table_start(),
1239            localvariable_len * sizeof(LocalVariableTableElement));
1240   }
1241   // Copy stackmap table
1242   if (m->has_stackmap_table()) {
1243     int code_attribute_length = m->stackmap_data()->length();
1244     Array<u1>* stackmap_data =
1245       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1246     memcpy((void*)stackmap_data->adr_at(0),
1247            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1248     newm->set_stackmap_data(stackmap_data);
1249   }
1250 
1251   // copy annotations over to new method
1252   newcm->copy_annotations_from(cm);
1253   return newm;
1254 }
1255 
1256 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
1257   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1258   // because we are not loading from core libraries
1259   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1260   // which does not use the class default class loader so we check for its loader here
1261   InstanceKlass* ik = InstanceKlass::cast(holder);
1262   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
1263     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1264   }
1265 
1266   // see if the klass name is well-known:
1267   Symbol* klass_name = ik->name();
1268   return vmSymbols::find_sid(klass_name);
1269 }
1270 
1271 void Method::init_intrinsic_id() {
1272   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1273   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1274   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1275   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1276 
1277   // the klass name is well-known:
1278   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1279   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1280 
1281   // ditto for method and signature:
1282   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1283   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1284       && name_id == vmSymbols::NO_SID)
1285     return;
1286   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1287   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1288       && sig_id == vmSymbols::NO_SID)  return;
1289   jshort flags = access_flags().as_short();
1290 
1291   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1292   if (id != vmIntrinsics::_none) {
1293     set_intrinsic_id(id);
1294     return;
1295   }
1296 
1297   // A few slightly irregular cases:
1298   switch (klass_id) {
1299   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1300     // Second chance: check in regular Math.
1301     switch (name_id) {
1302     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1303     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1304     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1305       // pretend it is the corresponding method in the non-strict class:
1306       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1307       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1308       break;
1309     }
1310     break;
1311 
1312   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
1313   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1314     if (!is_native())  break;
1315     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1316     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1317       id = vmIntrinsics::_none;
1318     break;
1319   }
1320 
1321   if (id != vmIntrinsics::_none) {
1322     // Set up its iid.  It is an alias method.
1323     set_intrinsic_id(id);
1324     return;
1325   }
1326 }
1327 
1328 // These two methods are static since a GC may move the Method
1329 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1330   if (THREAD->is_Compiler_thread()) {
1331     // There is nothing useful this routine can do from within the Compile thread.
1332     // Hopefully, the signature contains only well-known classes.
1333     // We could scan for this and return true/false, but the caller won't care.
1334     return false;
1335   }
1336   bool sig_is_loaded = true;
1337   Handle class_loader(THREAD, m->method_holder()->class_loader());
1338   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1339   ResourceMark rm(THREAD);
1340   Symbol*  signature = m->signature();
1341   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1342     if (ss.is_object()) {
1343       Symbol* sym = ss.as_symbol(CHECK_(false));
1344       Symbol*  name  = sym;
1345       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1346                                              protection_domain, THREAD);
1347       // We are loading classes eagerly. If a ClassNotFoundException or
1348       // a LinkageError was generated, be sure to ignore it.
1349       if (HAS_PENDING_EXCEPTION) {
1350         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1351             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1352           CLEAR_PENDING_EXCEPTION;
1353         } else {
1354           return false;
1355         }
1356       }
1357       if( klass == NULL) { sig_is_loaded = false; }
1358     }
1359   }
1360   return sig_is_loaded;
1361 }
1362 
1363 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1364   Handle class_loader(THREAD, m->method_holder()->class_loader());
1365   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1366   ResourceMark rm(THREAD);
1367   Symbol*  signature = m->signature();
1368   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1369     if (ss.type() == T_OBJECT) {
1370       Symbol* name = ss.as_symbol_or_null();
1371       if (name == NULL) return true;
1372       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1373       if (klass == NULL) return true;
1374     }
1375   }
1376   return false;
1377 }
1378 
1379 // Exposed so field engineers can debug VM
1380 void Method::print_short_name(outputStream* st) {
1381   ResourceMark rm;
1382 #ifdef PRODUCT
1383   st->print(" %s::", method_holder()->external_name());
1384 #else
1385   st->print(" %s::", method_holder()->internal_name());
1386 #endif
1387   name()->print_symbol_on(st);
1388   if (WizardMode) signature()->print_symbol_on(st);
1389   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1390     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1391 }
1392 
1393 // Comparer for sorting an object array containing
1394 // Method*s.
1395 static int method_comparator(Method* a, Method* b) {
1396   return a->name()->fast_compare(b->name());
1397 }
1398 
1399 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1400 // default_methods also uses this without the ordering for fast find_method
1401 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1402   int length = methods->length();
1403   if (length > 1) {
1404     {
1405       No_Safepoint_Verifier nsv;
1406       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1407     }
1408     // Reset method ordering
1409     if (set_idnums) {
1410       for (int i = 0; i < length; i++) {
1411         Method* m = methods->at(i);
1412         m->set_method_idnum(i);
1413         m->set_orig_method_idnum(i);
1414       }
1415     }
1416   }
1417 }
1418 
1419 //-----------------------------------------------------------------------------------
1420 // Non-product code unless JVM/TI needs it
1421 
1422 #if !defined(PRODUCT) || INCLUDE_JVMTI
1423 class SignatureTypePrinter : public SignatureTypeNames {
1424  private:
1425   outputStream* _st;
1426   bool _use_separator;
1427 
1428   void type_name(const char* name) {
1429     if (_use_separator) _st->print(", ");
1430     _st->print("%s", name);
1431     _use_separator = true;
1432   }
1433 
1434  public:
1435   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1436     _st = st;
1437     _use_separator = false;
1438   }
1439 
1440   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1441   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1442 };
1443 
1444 
1445 void Method::print_name(outputStream* st) {
1446   Thread *thread = Thread::current();
1447   ResourceMark rm(thread);
1448   SignatureTypePrinter sig(signature(), st);
1449   st->print("%s ", is_static() ? "static" : "virtual");
1450   sig.print_returntype();
1451   st->print(" %s.", method_holder()->internal_name());
1452   name()->print_symbol_on(st);
1453   st->print("(");
1454   sig.print_parameters();
1455   st->print(")");
1456 }
1457 #endif // !PRODUCT || INCLUDE_JVMTI
1458 
1459 
1460 //-----------------------------------------------------------------------------------
1461 // Non-product code
1462 
1463 #ifndef PRODUCT
1464 void Method::print_codes_on(outputStream* st) const {
1465   print_codes_on(0, code_size(), st);
1466 }
1467 
1468 void Method::print_codes_on(int from, int to, outputStream* st) const {
1469   Thread *thread = Thread::current();
1470   ResourceMark rm(thread);
1471   methodHandle mh (thread, (Method*)this);
1472   BytecodeStream s(mh);
1473   s.set_interval(from, to);
1474   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1475   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1476 }
1477 #endif // not PRODUCT
1478 
1479 
1480 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1481 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1482 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1483 // as end-of-stream terminator.
1484 
1485 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1486   // bci and line number does not compress into single byte.
1487   // Write out escape character and use regular compression for bci and line number.
1488   write_byte((jubyte)0xFF);
1489   write_signed_int(bci_delta);
1490   write_signed_int(line_delta);
1491 }
1492 
1493 // See comment in method.hpp which explains why this exists.
1494 #if defined(_M_AMD64) && _MSC_VER >= 1400
1495 #pragma optimize("", off)
1496 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1497   write_pair_inline(bci, line);
1498 }
1499 #pragma optimize("", on)
1500 #endif
1501 
1502 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1503   _bci = 0;
1504   _line = 0;
1505 };
1506 
1507 
1508 bool CompressedLineNumberReadStream::read_pair() {
1509   jubyte next = read_byte();
1510   // Check for terminator
1511   if (next == 0) return false;
1512   if (next == 0xFF) {
1513     // Escape character, regular compression used
1514     _bci  += read_signed_int();
1515     _line += read_signed_int();
1516   } else {
1517     // Single byte compression used
1518     _bci  += next >> 3;
1519     _line += next & 0x7;
1520   }
1521   return true;
1522 }
1523 
1524 
1525 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1526   BreakpointInfo* bp = method_holder()->breakpoints();
1527   for (; bp != NULL; bp = bp->next()) {
1528     if (bp->match(this, bci)) {
1529       return bp->orig_bytecode();
1530     }
1531   }
1532   {
1533     ResourceMark rm;
1534     fatal(err_msg("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci));
1535   }
1536   return Bytecodes::_shouldnotreachhere;
1537 }
1538 
1539 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1540   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1541   BreakpointInfo* bp = method_holder()->breakpoints();
1542   for (; bp != NULL; bp = bp->next()) {
1543     if (bp->match(this, bci)) {
1544       bp->set_orig_bytecode(code);
1545       // and continue, in case there is more than one
1546     }
1547   }
1548 }
1549 
1550 void Method::set_breakpoint(int bci) {
1551   InstanceKlass* ik = method_holder();
1552   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1553   bp->set_next(ik->breakpoints());
1554   ik->set_breakpoints(bp);
1555   // do this last:
1556   bp->set(this);
1557 }
1558 
1559 static void clear_matches(Method* m, int bci) {
1560   InstanceKlass* ik = m->method_holder();
1561   BreakpointInfo* prev_bp = NULL;
1562   BreakpointInfo* next_bp;
1563   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1564     next_bp = bp->next();
1565     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1566     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1567       // do this first:
1568       bp->clear(m);
1569       // unhook it
1570       if (prev_bp != NULL)
1571         prev_bp->set_next(next_bp);
1572       else
1573         ik->set_breakpoints(next_bp);
1574       delete bp;
1575       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1576       // at same location. So we have multiple matching (method_index and bci)
1577       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1578       // breakpoint for clear_breakpoint request and keep all other method versions
1579       // BreakpointInfo for future clear_breakpoint request.
1580       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1581       // which is being called when class is unloaded. We delete all the Breakpoint
1582       // information for all versions of method. We may not correctly restore the original
1583       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1584       // so these methods won't be used anymore.
1585       if (bci >= 0) {
1586         break;
1587       }
1588     } else {
1589       // This one is a keeper.
1590       prev_bp = bp;
1591     }
1592   }
1593 }
1594 
1595 void Method::clear_breakpoint(int bci) {
1596   assert(bci >= 0, "");
1597   clear_matches(this, bci);
1598 }
1599 
1600 void Method::clear_all_breakpoints() {
1601   clear_matches(this, -1);
1602 }
1603 
1604 
1605 int Method::invocation_count() {
1606   MethodCounters *mcs = method_counters();
1607   if (TieredCompilation) {
1608     MethodData* const mdo = method_data();
1609     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1610         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1611       return InvocationCounter::count_limit;
1612     } else {
1613       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1614              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1615     }
1616   } else {
1617     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1618   }
1619 }
1620 
1621 int Method::backedge_count() {
1622   MethodCounters *mcs = method_counters();
1623   if (TieredCompilation) {
1624     MethodData* const mdo = method_data();
1625     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1626         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1627       return InvocationCounter::count_limit;
1628     } else {
1629       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1630              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1631     }
1632   } else {
1633     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1634   }
1635 }
1636 
1637 int Method::highest_comp_level() const {
1638   const MethodCounters* mcs = method_counters();
1639   if (mcs != NULL) {
1640     return mcs->highest_comp_level();
1641   } else {
1642     return CompLevel_none;
1643   }
1644 }
1645 
1646 int Method::highest_osr_comp_level() const {
1647   const MethodCounters* mcs = method_counters();
1648   if (mcs != NULL) {
1649     return mcs->highest_osr_comp_level();
1650   } else {
1651     return CompLevel_none;
1652   }
1653 }
1654 
1655 void Method::set_highest_comp_level(int level) {
1656   MethodCounters* mcs = method_counters();
1657   if (mcs != NULL) {
1658     mcs->set_highest_comp_level(level);
1659   }
1660 }
1661 
1662 void Method::set_highest_osr_comp_level(int level) {
1663   MethodCounters* mcs = method_counters();
1664   if (mcs != NULL) {
1665     mcs->set_highest_osr_comp_level(level);
1666   }
1667 }
1668 
1669 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1670   _bci = bci;
1671   _name_index = m->name_index();
1672   _signature_index = m->signature_index();
1673   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1674   if (_orig_bytecode == Bytecodes::_breakpoint)
1675     _orig_bytecode = m->orig_bytecode_at(_bci);
1676   _next = NULL;
1677 }
1678 
1679 void BreakpointInfo::set(Method* method) {
1680 #ifdef ASSERT
1681   {
1682     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1683     if (code == Bytecodes::_breakpoint)
1684       code = method->orig_bytecode_at(_bci);
1685     assert(orig_bytecode() == code, "original bytecode must be the same");
1686   }
1687 #endif
1688   Thread *thread = Thread::current();
1689   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1690   method->incr_number_of_breakpoints(thread);
1691   SystemDictionary::notice_modification();
1692   {
1693     // Deoptimize all dependents on this method
1694     HandleMark hm(thread);
1695     methodHandle mh(thread, method);
1696     Universe::flush_dependents_on_method(mh);
1697   }
1698 }
1699 
1700 void BreakpointInfo::clear(Method* method) {
1701   *method->bcp_from(_bci) = orig_bytecode();
1702   assert(method->number_of_breakpoints() > 0, "must not go negative");
1703   method->decr_number_of_breakpoints(Thread::current());
1704 }
1705 
1706 // jmethodID handling
1707 
1708 // This is a block allocating object, sort of like JNIHandleBlock, only a
1709 // lot simpler.  There aren't many of these, they aren't long, they are rarely
1710 // deleted and so we can do some suboptimal things.
1711 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1712 // never get rid of it.
1713 // It would be nice to be able to parameterize the number of methods for
1714 // the null_class_loader but then we'd have to turn this and ClassLoaderData
1715 // into templates.
1716 
1717 // I feel like this brain dead class should exist somewhere in the STL
1718 
1719 class JNIMethodBlock : public CHeapObj<mtClass> {
1720   enum { number_of_methods = 8 };
1721 
1722   Method*         _methods[number_of_methods];
1723   int             _top;
1724   JNIMethodBlock* _next;
1725  public:
1726   static Method* const _free_method;
1727 
1728   JNIMethodBlock() : _next(NULL), _top(0) {
1729     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
1730   }
1731 
1732   Method** add_method(Method* m) {
1733     if (_top < number_of_methods) {
1734       // top points to the next free entry.
1735       int i = _top;
1736       _methods[i] = m;
1737       _top++;
1738       return &_methods[i];
1739     } else if (_top == number_of_methods) {
1740       // if the next free entry ran off the block see if there's a free entry
1741       for (int i = 0; i< number_of_methods; i++) {
1742         if (_methods[i] == _free_method) {
1743           _methods[i] = m;
1744           return &_methods[i];
1745         }
1746       }
1747       // Only check each block once for frees.  They're very unlikely.
1748       // Increment top past the end of the block.
1749       _top++;
1750     }
1751     // need to allocate a next block.
1752     if (_next == NULL) {
1753       _next = new JNIMethodBlock();
1754     }
1755     return _next->add_method(m);
1756   }
1757 
1758   bool contains(Method** m) {
1759     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1760       for (int i = 0; i< number_of_methods; i++) {
1761         if (&(b->_methods[i]) == m) {
1762           return true;
1763         }
1764       }
1765     }
1766     return false;  // not found
1767   }
1768 
1769   // Doesn't really destroy it, just marks it as free so it can be reused.
1770   void destroy_method(Method** m) {
1771 #ifdef ASSERT
1772     assert(contains(m), "should be a methodID");
1773 #endif // ASSERT
1774     *m = _free_method;
1775   }
1776   void clear_method(Method* m) {
1777     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1778       for (int i = 0; i< number_of_methods; i++) {
1779         if (b->_methods[i] == m) {
1780           b->_methods[i] = NULL;
1781         }
1782       }
1783     }
1784     // not found
1785   }
1786 
1787   // During class unloading the methods are cleared, which is different
1788   // than freed.
1789   void clear_all_methods() {
1790     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1791       for (int i = 0; i< number_of_methods; i++) {
1792         b->_methods[i] = NULL;
1793       }
1794     }
1795   }
1796 #ifndef PRODUCT
1797   int count_methods() {
1798     // count all allocated methods
1799     int count = 0;
1800     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
1801       for (int i = 0; i< number_of_methods; i++) {
1802         if (b->_methods[i] != _free_method) count++;
1803       }
1804     }
1805     return count;
1806   }
1807 #endif // PRODUCT
1808 };
1809 
1810 // Something that can't be mistaken for an address or a markOop
1811 Method* const JNIMethodBlock::_free_method = (Method*)55;
1812 
1813 // Add a method id to the jmethod_ids
1814 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1815   ClassLoaderData* cld = loader_data;
1816 
1817   if (!SafepointSynchronize::is_at_safepoint()) {
1818     // Have to add jmethod_ids() to class loader data thread-safely.
1819     // Also have to add the method to the list safely, which the cld lock
1820     // protects as well.
1821     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1822     if (cld->jmethod_ids() == NULL) {
1823       cld->set_jmethod_ids(new JNIMethodBlock());
1824     }
1825     // jmethodID is a pointer to Method*
1826     return (jmethodID)cld->jmethod_ids()->add_method(m);
1827   } else {
1828     // At safepoint, we are single threaded and can set this.
1829     if (cld->jmethod_ids() == NULL) {
1830       cld->set_jmethod_ids(new JNIMethodBlock());
1831     }
1832     // jmethodID is a pointer to Method*
1833     return (jmethodID)cld->jmethod_ids()->add_method(m);
1834   }
1835 }
1836 
1837 // Mark a jmethodID as free.  This is called when there is a data race in
1838 // InstanceKlass while creating the jmethodID cache.
1839 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
1840   ClassLoaderData* cld = loader_data;
1841   Method** ptr = (Method**)m;
1842   assert(cld->jmethod_ids() != NULL, "should have method handles");
1843   cld->jmethod_ids()->destroy_method(ptr);
1844 }
1845 
1846 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
1847   // Can't assert the method_holder is the same because the new method has the
1848   // scratch method holder.
1849   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
1850            == new_method->method_holder()->class_loader(),
1851          "changing to a different class loader");
1852   // Just change the method in place, jmethodID pointer doesn't change.
1853   *((Method**)jmid) = new_method;
1854 }
1855 
1856 bool Method::is_method_id(jmethodID mid) {
1857   Method* m = resolve_jmethod_id(mid);
1858   if (m == NULL) {
1859     return false;
1860   }
1861   InstanceKlass* ik = m->method_holder();
1862   if (ik == NULL) {
1863     return false;
1864   }
1865   ClassLoaderData* cld = ik->class_loader_data();
1866   if (cld->jmethod_ids() == NULL) return false;
1867   return (cld->jmethod_ids()->contains((Method**)mid));
1868 }
1869 
1870 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
1871   if (mid == NULL) return NULL;
1872   if (!Method::is_method_id(mid)) {
1873     return NULL;
1874   }
1875   Method* o = resolve_jmethod_id(mid);
1876   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
1877     return NULL;
1878   }
1879   return o;
1880 };
1881 
1882 void Method::clear_jmethod_id(ClassLoaderData* loader_data) {
1883   loader_data->jmethod_ids()->clear_method(this);
1884 }
1885 
1886 void Method::set_on_stack(const bool value) {
1887   // Set both the method itself and its constant pool.  The constant pool
1888   // on stack means some method referring to it is also on the stack.
1889   constants()->set_on_stack(value);
1890 
1891   bool succeeded = _access_flags.set_on_stack(value);
1892   if (value && succeeded) {
1893     MetadataOnStackMark::record(this, Thread::current());
1894   }
1895 }
1896 
1897 // Called when the class loader is unloaded to make all methods weak.
1898 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
1899   loader_data->jmethod_ids()->clear_all_methods();
1900 }
1901 
1902 bool Method::has_method_vptr(const void* ptr) {
1903   Method m;
1904   // This assumes that the vtbl pointer is the first word of a C++ object.
1905   // This assumption is also in universe.cpp patch_klass_vtble
1906   void* vtbl2 = dereference_vptr((const void*)&m);
1907   void* this_vtbl = dereference_vptr(ptr);
1908   return vtbl2 == this_vtbl;
1909 }
1910 
1911 // Check that this pointer is valid by checking that the vtbl pointer matches
1912 bool Method::is_valid_method() const {
1913   if (this == NULL) {
1914     return false;
1915   } else if (!is_metaspace_object()) {
1916     return false;
1917   } else {
1918     return has_method_vptr((const void*)this);
1919   }
1920 }
1921 
1922 #ifndef PRODUCT
1923 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
1924   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
1925 }
1926 #endif // PRODUCT
1927 
1928 
1929 // Printing
1930 
1931 #ifndef PRODUCT
1932 
1933 void Method::print_on(outputStream* st) const {
1934   ResourceMark rm;
1935   assert(is_method(), "must be method");
1936   st->print_cr("%s", internal_name());
1937   // get the effect of PrintOopAddress, always, for methods:
1938   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
1939   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
1940   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
1941   constants()->print_value_on(st); st->cr();
1942   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
1943   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
1944   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
1945   st->print_cr(" - max stack:         %d",   max_stack());
1946   st->print_cr(" - max locals:        %d",   max_locals());
1947   st->print_cr(" - size of params:    %d",   size_of_parameters());
1948   st->print_cr(" - method size:       %d",   method_size());
1949   if (intrinsic_id() != vmIntrinsics::_none)
1950     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
1951   if (highest_comp_level() != CompLevel_none)
1952     st->print_cr(" - highest level:     %d", highest_comp_level());
1953   st->print_cr(" - vtable index:      %d",   _vtable_index);
1954   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
1955   st->print(   " - adapters:          ");
1956   AdapterHandlerEntry* a = ((Method*)this)->adapter();
1957   if (a == NULL)
1958     st->print_cr(INTPTR_FORMAT, a);
1959   else
1960     a->print_adapter_on(st);
1961   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
1962   st->print_cr(" - code size:         %d",   code_size());
1963   if (code_size() != 0) {
1964     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
1965     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
1966   }
1967   if (method_data() != NULL) {
1968     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
1969   }
1970   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
1971   if (checked_exceptions_length() > 0) {
1972     CheckedExceptionElement* table = checked_exceptions_start();
1973     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
1974     if (Verbose) {
1975       for (int i = 0; i < checked_exceptions_length(); i++) {
1976         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
1977       }
1978     }
1979   }
1980   if (has_linenumber_table()) {
1981     u_char* table = compressed_linenumber_table();
1982     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
1983     if (Verbose) {
1984       CompressedLineNumberReadStream stream(table);
1985       while (stream.read_pair()) {
1986         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
1987       }
1988     }
1989   }
1990   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
1991   if (localvariable_table_length() > 0) {
1992     LocalVariableTableElement* table = localvariable_table_start();
1993     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
1994     if (Verbose) {
1995       for (int i = 0; i < localvariable_table_length(); i++) {
1996         int bci = table[i].start_bci;
1997         int len = table[i].length;
1998         const char* name = constants()->printable_name_at(table[i].name_cp_index);
1999         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2000         int slot = table[i].slot;
2001         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2002       }
2003     }
2004   }
2005   if (code() != NULL) {
2006     st->print   (" - compiled code: ");
2007     code()->print_value_on(st);
2008   }
2009   if (is_native()) {
2010     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
2011     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
2012   }
2013 }
2014 
2015 #endif //PRODUCT
2016 
2017 void Method::print_value_on(outputStream* st) const {
2018   assert(is_method(), "must be method");
2019   st->print("%s", internal_name());
2020   print_address_on(st);
2021   st->print(" ");
2022   name()->print_value_on(st);
2023   st->print(" ");
2024   signature()->print_value_on(st);
2025   st->print(" in ");
2026   method_holder()->print_value_on(st);
2027   if (WizardMode) st->print("#%d", _vtable_index);
2028   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2029   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2030 }
2031 
2032 #if INCLUDE_SERVICES
2033 // Size Statistics
2034 void Method::collect_statistics(KlassSizeStats *sz) const {
2035   int mysize = sz->count(this);
2036   sz->_method_bytes += mysize;
2037   sz->_method_all_bytes += mysize;
2038   sz->_rw_bytes += mysize;
2039 
2040   if (constMethod()) {
2041     constMethod()->collect_statistics(sz);
2042   }
2043   if (method_data()) {
2044     method_data()->collect_statistics(sz);
2045   }
2046 }
2047 #endif // INCLUDE_SERVICES
2048 
2049 // Verification
2050 
2051 void Method::verify_on(outputStream* st) {
2052   guarantee(is_method(), "object must be method");
2053   guarantee(constants()->is_constantPool(), "should be constant pool");
2054   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2055   MethodData* md = method_data();
2056   guarantee(md == NULL ||
2057       md->is_methodData(), "should be method data");
2058 }
--- EOF ---