src/share/vm/oops/method.cpp

Mon, 12 Dec 2016 12:53:38 +0100

author
zmajo
date
Mon, 12 Dec 2016 12:53:38 +0100
changeset 8664
00cbb581da94
parent 8583
d18eb5b5a3d6
child 8717
77d9c9da7188
permissions
-rw-r--r--

8157181: Compilers accept modification of final fields outside initializer methods
Summary: Track initialized final field updates; disable constant folding if an update is detected.
Reviewed-by: vlivanov, dnsimon, forax, never, kvn, coleenp

     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  */
    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/metaspaceShared.hpp"
    40 #include "memory/oopFactory.hpp"
    41 #include "oops/constMethod.hpp"
    42 #include "oops/methodData.hpp"
    43 #include "oops/method.hpp"
    44 #include "oops/oop.inline.hpp"
    45 #include "oops/symbol.hpp"
    46 #include "prims/jvmtiExport.hpp"
    47 #include "prims/methodHandles.hpp"
    48 #include "prims/nativeLookup.hpp"
    49 #include "runtime/arguments.hpp"
    50 #include "runtime/compilationPolicy.hpp"
    51 #include "runtime/frame.inline.hpp"
    52 #include "runtime/handles.inline.hpp"
    53 #include "runtime/orderAccess.inline.hpp"
    54 #include "runtime/relocator.hpp"
    55 #include "runtime/sharedRuntime.hpp"
    56 #include "runtime/signature.hpp"
    57 #include "utilities/quickSort.hpp"
    58 #include "utilities/xmlstream.hpp"
    60 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
    62 // Implementation of Method
    64 Method* Method::allocate(ClassLoaderData* loader_data,
    65                          int byte_code_size,
    66                          AccessFlags access_flags,
    67                          InlineTableSizes* sizes,
    68                          ConstMethod::MethodType method_type,
    69                          TRAPS) {
    70   assert(!access_flags.is_native() || byte_code_size == 0,
    71          "native methods should not contain byte codes");
    72   ConstMethod* cm = ConstMethod::allocate(loader_data,
    73                                           byte_code_size,
    74                                           sizes,
    75                                           method_type,
    76                                           CHECK_NULL);
    78   int size = Method::size(access_flags.is_native());
    80   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, size);
    81 }
    83 Method::Method(ConstMethod* xconst, AccessFlags access_flags, int size) {
    84   No_Safepoint_Verifier no_safepoint;
    85   set_constMethod(xconst);
    86   set_access_flags(access_flags);
    87   set_method_size(size);
    88   set_intrinsic_id(vmIntrinsics::_none);
    89   set_jfr_towrite(false);
    90   set_force_inline(false);
    91   set_hidden(false);
    92   set_dont_inline(false);
    93   set_has_injected_profile(false);
    94   set_method_data(NULL);
    95   clear_method_counters();
    96   set_vtable_index(Method::garbage_vtable_index);
    98   // Fix and bury in Method*
    99   set_interpreter_entry(NULL); // sets i2i entry and from_int
   100   set_adapter_entry(NULL);
   101   clear_code(); // from_c/from_i get set to c2i/i2i
   103   if (access_flags.is_native()) {
   104     clear_native_function();
   105     set_signature_handler(NULL);
   106   }
   108   NOT_PRODUCT(set_compiled_invocation_count(0);)
   109 }
   111 // Release Method*.  The nmethod will be gone when we get here because
   112 // we've walked the code cache.
   113 void Method::deallocate_contents(ClassLoaderData* loader_data) {
   114   clear_jmethod_id(loader_data);
   115   MetadataFactory::free_metadata(loader_data, constMethod());
   116   set_constMethod(NULL);
   117   MetadataFactory::free_metadata(loader_data, method_data());
   118   set_method_data(NULL);
   119   MetadataFactory::free_metadata(loader_data, method_counters());
   120   clear_method_counters();
   121   // The nmethod will be gone when we get here.
   122   if (code() != NULL) _code = NULL;
   123 }
   125 address Method::get_i2c_entry() {
   126   assert(_adapter != NULL, "must have");
   127   return _adapter->get_i2c_entry();
   128 }
   130 address Method::get_c2i_entry() {
   131   assert(_adapter != NULL, "must have");
   132   return _adapter->get_c2i_entry();
   133 }
   135 address Method::get_c2i_unverified_entry() {
   136   assert(_adapter != NULL, "must have");
   137   return _adapter->get_c2i_unverified_entry();
   138 }
   140 char* Method::name_and_sig_as_C_string() const {
   141   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
   142 }
   144 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
   145   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
   146 }
   148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
   149   const char* klass_name = klass->external_name();
   150   int klass_name_len  = (int)strlen(klass_name);
   151   int method_name_len = method_name->utf8_length();
   152   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
   153   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
   154   strcpy(dest, klass_name);
   155   dest[klass_name_len] = '.';
   156   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
   157   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
   158   dest[len] = 0;
   159   return dest;
   160 }
   162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
   163   Symbol* klass_name = klass->name();
   164   klass_name->as_klass_external_name(buf, size);
   165   int len = (int)strlen(buf);
   167   if (len < size - 1) {
   168     buf[len++] = '.';
   170     method_name->as_C_string(&(buf[len]), size - len);
   171     len = (int)strlen(buf);
   173     signature->as_C_string(&(buf[len]), size - len);
   174   }
   176   return buf;
   177 }
   179 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
   180   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
   181   // access exception table
   182   ExceptionTable table(mh());
   183   int length = table.length();
   184   // iterate through all entries sequentially
   185   constantPoolHandle pool(THREAD, mh->constants());
   186   for (int i = 0; i < length; i ++) {
   187     //reacquire the table in case a GC happened
   188     ExceptionTable table(mh());
   189     int beg_bci = table.start_pc(i);
   190     int end_bci = table.end_pc(i);
   191     assert(beg_bci <= end_bci, "inconsistent exception table");
   192     if (beg_bci <= throw_bci && throw_bci < end_bci) {
   193       // exception handler bci range covers throw_bci => investigate further
   194       int handler_bci = table.handler_pc(i);
   195       int klass_index = table.catch_type_index(i);
   196       if (klass_index == 0) {
   197         return handler_bci;
   198       } else if (ex_klass.is_null()) {
   199         return handler_bci;
   200       } else {
   201         // we know the exception class => get the constraint class
   202         // this may require loading of the constraint class; if verification
   203         // fails or some other exception occurs, return handler_bci
   204         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
   205         KlassHandle klass = KlassHandle(THREAD, k);
   206         assert(klass.not_null(), "klass not loaded");
   207         if (ex_klass->is_subtype_of(klass())) {
   208           return handler_bci;
   209         }
   210       }
   211     }
   212   }
   214   return -1;
   215 }
   217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
   219   Thread* myThread    = Thread::current();
   220   methodHandle h_this(myThread, this);
   221 #ifdef ASSERT
   222   bool has_capability = myThread->is_VM_thread() ||
   223                         myThread->is_ConcurrentGC_thread() ||
   224                         myThread->is_GC_task_thread();
   226   if (!has_capability) {
   227     if (!VerifyStack && !VerifyLastFrame) {
   228       // verify stack calls this outside VM thread
   229       warning("oopmap should only be accessed by the "
   230               "VM, GC task or CMS threads (or during debugging)");
   231       InterpreterOopMap local_mask;
   232       method_holder()->mask_for(h_this, bci, &local_mask);
   233       local_mask.print();
   234     }
   235   }
   236 #endif
   237   method_holder()->mask_for(h_this, bci, mask);
   238   return;
   239 }
   242 int Method::bci_from(address bcp) const {
   243 #ifdef ASSERT
   244   { ResourceMark rm;
   245   assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
   246          err_msg("bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", bcp, name_and_sig_as_C_string()));
   247   }
   248 #endif
   249   return bcp - code_base();
   250 }
   253 // Return (int)bcx if it appears to be a valid BCI.
   254 // Return bci_from((address)bcx) if it appears to be a valid BCP.
   255 // Return -1 otherwise.
   256 // Used by profiling code, when invalid data is a possibility.
   257 // The caller is responsible for validating the Method* itself.
   258 int Method::validate_bci_from_bcx(intptr_t bcx) const {
   259   // keep bci as -1 if not a valid bci
   260   int bci = -1;
   261   if (bcx == 0 || (address)bcx == code_base()) {
   262     // code_size() may return 0 and we allow 0 here
   263     // the method may be native
   264     bci = 0;
   265   } else if (frame::is_bci(bcx)) {
   266     if (bcx < code_size()) {
   267       bci = (int)bcx;
   268     }
   269   } else if (contains((address)bcx)) {
   270     bci = (address)bcx - code_base();
   271   }
   272   // Assert that if we have dodged any asserts, bci is negative.
   273   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
   274   return bci;
   275 }
   277 address Method::bcp_from(int bci) const {
   278   assert((is_native() && bci == 0)  || (!is_native() && 0 <= bci && bci < code_size()), err_msg("illegal bci: %d", bci));
   279   address bcp = code_base() + bci;
   280   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
   281   return bcp;
   282 }
   285 int Method::size(bool is_native) {
   286   // If native, then include pointers for native_function and signature_handler
   287   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
   288   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
   289   return align_object_size(header_size() + extra_words);
   290 }
   293 Symbol* Method::klass_name() const {
   294   Klass* k = method_holder();
   295   assert(k->is_klass(), "must be klass");
   296   InstanceKlass* ik = (InstanceKlass*) k;
   297   return ik->name();
   298 }
   301 // Attempt to return method oop to original state.  Clear any pointers
   302 // (to objects outside the shared spaces).  We won't be able to predict
   303 // where they should point in a new JVM.  Further initialize some
   304 // entries now in order allow them to be write protected later.
   306 void Method::remove_unshareable_info() {
   307   unlink_method();
   308 }
   310 void Method::set_vtable_index(int index) {
   311   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
   312     // At runtime initialize_vtable is rerun as part of link_class_impl()
   313     // for a shared class loaded by the non-boot loader to obtain the loader
   314     // constraints based on the runtime classloaders' context.
   315     return; // don't write into the shared class
   316   } else {
   317     _vtable_index = index;
   318   }
   319 }
   321 void Method::set_itable_index(int index) {
   322   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
   323     // At runtime initialize_itable is rerun as part of link_class_impl()
   324     // for a shared class loaded by the non-boot loader to obtain the loader
   325     // constraints based on the runtime classloaders' context. The dumptime
   326     // itable index should be the same as the runtime index.
   327     assert(_vtable_index == itable_index_max - index,
   328            "archived itable index is different from runtime index");
   329     return; // don’t write into the shared class
   330   } else {
   331     _vtable_index = itable_index_max - index;
   332   }
   333   assert(valid_itable_index(), "");
   334 }
   338 bool Method::was_executed_more_than(int n) {
   339   // Invocation counter is reset when the Method* is compiled.
   340   // If the method has compiled code we therefore assume it has
   341   // be excuted more than n times.
   342   if (is_accessor() || is_empty_method() || (code() != NULL)) {
   343     // interpreter doesn't bump invocation counter of trivial methods
   344     // compiler does not bump invocation counter of compiled methods
   345     return true;
   346   }
   347   else if ((method_counters() != NULL &&
   348             method_counters()->invocation_counter()->carry()) ||
   349            (method_data() != NULL &&
   350             method_data()->invocation_counter()->carry())) {
   351     // The carry bit is set when the counter overflows and causes
   352     // a compilation to occur.  We don't know how many times
   353     // the counter has been reset, so we simply assume it has
   354     // been executed more than n times.
   355     return true;
   356   } else {
   357     return invocation_count() > n;
   358   }
   359 }
   361 #ifndef PRODUCT
   362 void Method::print_invocation_count() {
   363   if (is_static()) tty->print("static ");
   364   if (is_final()) tty->print("final ");
   365   if (is_synchronized()) tty->print("synchronized ");
   366   if (is_native()) tty->print("native ");
   367   method_holder()->name()->print_symbol_on(tty);
   368   tty->print(".");
   369   name()->print_symbol_on(tty);
   370   signature()->print_symbol_on(tty);
   372   if (WizardMode) {
   373     // dump the size of the byte codes
   374     tty->print(" {%d}", code_size());
   375   }
   376   tty->cr();
   378   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
   379   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
   380   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
   381   if (CountCompiledCalls) {
   382     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
   383   }
   385 }
   386 #endif
   388 // Build a MethodData* object to hold information about this method
   389 // collected in the interpreter.
   390 void Method::build_interpreter_method_data(methodHandle method, TRAPS) {
   391   // Do not profile method if current thread holds the pending list lock,
   392   // which avoids deadlock for acquiring the MethodData_lock.
   393   if (InstanceRefKlass::owns_pending_list_lock((JavaThread*)THREAD)) {
   394     return;
   395   }
   397   // Grab a lock here to prevent multiple
   398   // MethodData*s from being created.
   399   MutexLocker ml(MethodData_lock, THREAD);
   400   if (method->method_data() == NULL) {
   401     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
   402     MethodData* method_data = MethodData::allocate(loader_data, method, CHECK);
   403     method->set_method_data(method_data);
   404     if (PrintMethodData && (Verbose || WizardMode)) {
   405       ResourceMark rm(THREAD);
   406       tty->print("build_interpreter_method_data for ");
   407       method->print_name(tty);
   408       tty->cr();
   409       // At the end of the run, the MDO, full of data, will be dumped.
   410     }
   411   }
   412 }
   414 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
   415   methodHandle mh(m);
   416   ClassLoaderData* loader_data = mh->method_holder()->class_loader_data();
   417   MethodCounters* counters = MethodCounters::allocate(loader_data, CHECK_NULL);
   418   if (!mh->init_method_counters(counters)) {
   419     MetadataFactory::free_metadata(loader_data, counters);
   420   }
   421   return mh->method_counters();
   422 }
   424 void Method::cleanup_inline_caches() {
   425   // The current system doesn't use inline caches in the interpreter
   426   // => nothing to do (keep this method around for future use)
   427 }
   430 int Method::extra_stack_words() {
   431   // not an inline function, to avoid a header dependency on Interpreter
   432   return extra_stack_entries() * Interpreter::stackElementSize;
   433 }
   436 void Method::compute_size_of_parameters(Thread *thread) {
   437   ArgumentSizeComputer asc(signature());
   438   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
   439 }
   441 BasicType Method::result_type() const {
   442   ResultTypeFinder rtf(signature());
   443   return rtf.type();
   444 }
   447 bool Method::is_empty_method() const {
   448   return  code_size() == 1
   449       && *code_base() == Bytecodes::_return;
   450 }
   453 bool Method::is_vanilla_constructor() const {
   454   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
   455   // which only calls the superclass vanilla constructor and possibly does stores of
   456   // zero constants to local fields:
   457   //
   458   //   aload_0
   459   //   invokespecial
   460   //   indexbyte1
   461   //   indexbyte2
   462   //
   463   // followed by an (optional) sequence of:
   464   //
   465   //   aload_0
   466   //   aconst_null / iconst_0 / fconst_0 / dconst_0
   467   //   putfield
   468   //   indexbyte1
   469   //   indexbyte2
   470   //
   471   // followed by:
   472   //
   473   //   return
   475   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
   476   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
   477   int size = code_size();
   478   // Check if size match
   479   if (size == 0 || size % 5 != 0) return false;
   480   address cb = code_base();
   481   int last = size - 1;
   482   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
   483     // Does not call superclass default constructor
   484     return false;
   485   }
   486   // Check optional sequence
   487   for (int i = 4; i < last; i += 5) {
   488     if (cb[i] != Bytecodes::_aload_0) return false;
   489     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
   490     if (cb[i+2] != Bytecodes::_putfield) return false;
   491   }
   492   return true;
   493 }
   496 bool Method::compute_has_loops_flag() {
   497   BytecodeStream bcs(this);
   498   Bytecodes::Code bc;
   500   while ((bc = bcs.next()) >= 0) {
   501     switch( bc ) {
   502       case Bytecodes::_ifeq:
   503       case Bytecodes::_ifnull:
   504       case Bytecodes::_iflt:
   505       case Bytecodes::_ifle:
   506       case Bytecodes::_ifne:
   507       case Bytecodes::_ifnonnull:
   508       case Bytecodes::_ifgt:
   509       case Bytecodes::_ifge:
   510       case Bytecodes::_if_icmpeq:
   511       case Bytecodes::_if_icmpne:
   512       case Bytecodes::_if_icmplt:
   513       case Bytecodes::_if_icmpgt:
   514       case Bytecodes::_if_icmple:
   515       case Bytecodes::_if_icmpge:
   516       case Bytecodes::_if_acmpeq:
   517       case Bytecodes::_if_acmpne:
   518       case Bytecodes::_goto:
   519       case Bytecodes::_jsr:
   520         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
   521         break;
   523       case Bytecodes::_goto_w:
   524       case Bytecodes::_jsr_w:
   525         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
   526         break;
   527     }
   528   }
   529   _access_flags.set_loops_flag_init();
   530   return _access_flags.has_loops();
   531 }
   533 bool Method::is_final_method(AccessFlags class_access_flags) const {
   534   // or "does_not_require_vtable_entry"
   535   // default method or overpass can occur, is not final (reuses vtable entry)
   536   // private methods get vtable entries for backward class compatibility.
   537   if (is_overpass() || is_default_method())  return false;
   538   return is_final() || class_access_flags.is_final();
   539 }
   541 bool Method::is_final_method() const {
   542   return is_final_method(method_holder()->access_flags());
   543 }
   545 bool Method::is_default_method() const {
   546   if (method_holder() != NULL &&
   547       method_holder()->is_interface() &&
   548       !is_abstract()) {
   549     return true;
   550   } else {
   551     return false;
   552   }
   553 }
   555 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
   556   if (is_final_method(class_access_flags))  return true;
   557 #ifdef ASSERT
   558   ResourceMark rm;
   559   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
   560   if (class_access_flags.is_interface()) {
   561       assert(is_nonv == is_static(), err_msg("is_nonv=%s", name_and_sig_as_C_string()));
   562   }
   563 #endif
   564   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
   565   return vtable_index() == nonvirtual_vtable_index;
   566 }
   568 bool Method::can_be_statically_bound() const {
   569   return can_be_statically_bound(method_holder()->access_flags());
   570 }
   572 bool Method::is_accessor() const {
   573   if (code_size() != 5) return false;
   574   if (size_of_parameters() != 1) return false;
   575   if (java_code_at(0) != Bytecodes::_aload_0 ) return false;
   576   if (java_code_at(1) != Bytecodes::_getfield) return false;
   577   if (java_code_at(4) != Bytecodes::_areturn &&
   578       java_code_at(4) != Bytecodes::_ireturn ) return false;
   579   return true;
   580 }
   582 bool Method::is_constant_getter() const {
   583   int last_index = code_size() - 1;
   584   // Check if the first 1-3 bytecodes are a constant push
   585   // and the last bytecode is a return.
   586   return (2 <= code_size() && code_size() <= 4 &&
   587           Bytecodes::is_const(java_code_at(0)) &&
   588           Bytecodes::length_for(java_code_at(0)) == last_index &&
   589           Bytecodes::is_return(java_code_at(last_index)));
   590 }
   592 bool Method::is_initializer() const {
   593   return is_object_initializer() || is_static_initializer();
   594 }
   596 bool Method::has_valid_initializer_flags() const {
   597   return (is_static() ||
   598           method_holder()->major_version() < 51);
   599 }
   601 bool Method::is_static_initializer() const {
   602   // For classfiles version 51 or greater, ensure that the clinit method is
   603   // static.  Non-static methods with the name "<clinit>" are not static
   604   // initializers. (older classfiles exempted for backward compatibility)
   605   return name() == vmSymbols::class_initializer_name() &&
   606          has_valid_initializer_flags();
   607 }
   609 bool Method::is_object_initializer() const {
   610    return name() == vmSymbols::object_initializer_name();
   611 }
   613 objArrayHandle Method::resolved_checked_exceptions_impl(Method* this_oop, TRAPS) {
   614   int length = this_oop->checked_exceptions_length();
   615   if (length == 0) {  // common case
   616     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
   617   } else {
   618     methodHandle h_this(THREAD, this_oop);
   619     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
   620     objArrayHandle mirrors (THREAD, m_oop);
   621     for (int i = 0; i < length; i++) {
   622       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
   623       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
   624       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
   625       mirrors->obj_at_put(i, k->java_mirror());
   626     }
   627     return mirrors;
   628   }
   629 };
   632 int Method::line_number_from_bci(int bci) const {
   633   if (bci == SynchronizationEntryBCI) bci = 0;
   634   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
   635   int best_bci  =  0;
   636   int best_line = -1;
   638   if (has_linenumber_table()) {
   639     // The line numbers are a short array of 2-tuples [start_pc, line_number].
   640     // Not necessarily sorted and not necessarily one-to-one.
   641     CompressedLineNumberReadStream stream(compressed_linenumber_table());
   642     while (stream.read_pair()) {
   643       if (stream.bci() == bci) {
   644         // perfect match
   645         return stream.line();
   646       } else {
   647         // update best_bci/line
   648         if (stream.bci() < bci && stream.bci() >= best_bci) {
   649           best_bci  = stream.bci();
   650           best_line = stream.line();
   651         }
   652       }
   653     }
   654   }
   655   return best_line;
   656 }
   659 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
   660   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
   661     Thread *thread = Thread::current();
   662     Symbol* klass_name = constants()->klass_name_at(klass_index);
   663     Handle loader(thread, method_holder()->class_loader());
   664     Handle prot  (thread, method_holder()->protection_domain());
   665     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
   666   } else {
   667     return true;
   668   }
   669 }
   672 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
   673   int klass_index = constants()->klass_ref_index_at(refinfo_index);
   674   if (must_be_resolved) {
   675     // Make sure klass is resolved in constantpool.
   676     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
   677   }
   678   return is_klass_loaded_by_klass_index(klass_index);
   679 }
   682 void Method::set_native_function(address function, bool post_event_flag) {
   683   assert(function != NULL, "use clear_native_function to unregister natives");
   684   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
   685   address* native_function = native_function_addr();
   687   // We can see racers trying to place the same native function into place. Once
   688   // is plenty.
   689   address current = *native_function;
   690   if (current == function) return;
   691   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
   692       function != NULL) {
   693     // native_method_throw_unsatisfied_link_error_entry() should only
   694     // be passed when post_event_flag is false.
   695     assert(function !=
   696       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
   697       "post_event_flag mis-match");
   699     // post the bind event, and possible change the bind function
   700     JvmtiExport::post_native_method_bind(this, &function);
   701   }
   702   *native_function = function;
   703   // This function can be called more than once. We must make sure that we always
   704   // use the latest registered method -> check if a stub already has been generated.
   705   // If so, we have to make it not_entrant.
   706   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
   707   if (nm != NULL) {
   708     nm->make_not_entrant();
   709   }
   710 }
   713 bool Method::has_native_function() const {
   714   if (is_method_handle_intrinsic())
   715     return false;  // special-cased in SharedRuntime::generate_native_wrapper
   716   address func = native_function();
   717   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
   718 }
   721 void Method::clear_native_function() {
   722   // Note: is_method_handle_intrinsic() is allowed here.
   723   set_native_function(
   724     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
   725     !native_bind_event_is_interesting);
   726   clear_code();
   727 }
   729 address Method::critical_native_function() {
   730   methodHandle mh(this);
   731   return NativeLookup::lookup_critical_entry(mh);
   732 }
   735 void Method::set_signature_handler(address handler) {
   736   address* signature_handler =  signature_handler_addr();
   737   *signature_handler = handler;
   738 }
   741 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
   742   if (PrintCompilation && report) {
   743     ttyLocker ttyl;
   744     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
   745     if (comp_level == CompLevel_all) {
   746       tty->print("all levels ");
   747     } else {
   748       tty->print("levels ");
   749       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
   750         tty->print("%d ", i);
   751       }
   752     }
   753     this->print_short_name(tty);
   754     int size = this->code_size();
   755     if (size > 0) {
   756       tty->print(" (%d bytes)", size);
   757     }
   758     if (reason != NULL) {
   759       tty->print("   %s", reason);
   760     }
   761     tty->cr();
   762   }
   763   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
   764     ttyLocker ttyl;
   765     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
   766                      os::current_thread_id(), is_osr, comp_level);
   767     if (reason != NULL) {
   768       xtty->print(" reason=\'%s\'", reason);
   769     }
   770     xtty->method(this);
   771     xtty->stamp();
   772     xtty->end_elem();
   773   }
   774 }
   776 bool Method::is_always_compilable() const {
   777   // Generated adapters must be compiled
   778   if (is_method_handle_intrinsic() && is_synthetic()) {
   779     assert(!is_not_c1_compilable(), "sanity check");
   780     assert(!is_not_c2_compilable(), "sanity check");
   781     return true;
   782   }
   784   return false;
   785 }
   787 bool Method::is_not_compilable(int comp_level) const {
   788   if (number_of_breakpoints() > 0)
   789     return true;
   790   if (is_always_compilable())
   791     return false;
   792   if (comp_level == CompLevel_any)
   793     return is_not_c1_compilable() || is_not_c2_compilable();
   794   if (is_c1_compile(comp_level))
   795     return is_not_c1_compilable();
   796   if (is_c2_compile(comp_level))
   797     return is_not_c2_compilable();
   798   return false;
   799 }
   801 // call this when compiler finds that this method is not compilable
   802 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
   803   if (is_always_compilable()) {
   804     // Don't mark a method which should be always compilable
   805     return;
   806   }
   807   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
   808   if (comp_level == CompLevel_all) {
   809     set_not_c1_compilable();
   810     set_not_c2_compilable();
   811   } else {
   812     if (is_c1_compile(comp_level))
   813       set_not_c1_compilable();
   814     if (is_c2_compile(comp_level))
   815       set_not_c2_compilable();
   816   }
   817   CompilationPolicy::policy()->disable_compilation(this);
   818   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
   819 }
   821 bool Method::is_not_osr_compilable(int comp_level) const {
   822   if (is_not_compilable(comp_level))
   823     return true;
   824   if (comp_level == CompLevel_any)
   825     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
   826   if (is_c1_compile(comp_level))
   827     return is_not_c1_osr_compilable();
   828   if (is_c2_compile(comp_level))
   829     return is_not_c2_osr_compilable();
   830   return false;
   831 }
   833 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
   834   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
   835   if (comp_level == CompLevel_all) {
   836     set_not_c1_osr_compilable();
   837     set_not_c2_osr_compilable();
   838   } else {
   839     if (is_c1_compile(comp_level))
   840       set_not_c1_osr_compilable();
   841     if (is_c2_compile(comp_level))
   842       set_not_c2_osr_compilable();
   843   }
   844   CompilationPolicy::policy()->disable_compilation(this);
   845   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
   846 }
   848 // Revert to using the interpreter and clear out the nmethod
   849 void Method::clear_code() {
   851   // this may be NULL if c2i adapters have not been made yet
   852   // Only should happen at allocate time.
   853   if (_adapter == NULL) {
   854     _from_compiled_entry    = NULL;
   855   } else {
   856     _from_compiled_entry    = _adapter->get_c2i_entry();
   857   }
   858   OrderAccess::storestore();
   859   _from_interpreted_entry = _i2i_entry;
   860   OrderAccess::storestore();
   861   _code = NULL;
   862 }
   864 // Called by class data sharing to remove any entry points (which are not shared)
   865 void Method::unlink_method() {
   866   _code = NULL;
   867   _i2i_entry = NULL;
   868   _from_interpreted_entry = NULL;
   869   if (is_native()) {
   870     *native_function_addr() = NULL;
   871     set_signature_handler(NULL);
   872   }
   873   NOT_PRODUCT(set_compiled_invocation_count(0);)
   874   _adapter = NULL;
   875   _from_compiled_entry = NULL;
   877   // In case of DumpSharedSpaces, _method_data should always be NULL.
   878   //
   879   // During runtime (!DumpSharedSpaces), when we are cleaning a
   880   // shared class that failed to load, this->link_method() may
   881   // have already been called (before an exception happened), so
   882   // this->_method_data may not be NULL.
   883   assert(!DumpSharedSpaces || _method_data == NULL, "unexpected method data?");
   885   set_method_data(NULL);
   886   clear_method_counters();
   887 }
   889 // Called when the method_holder is getting linked. Setup entrypoints so the method
   890 // is ready to be called from interpreter, compiler, and vtables.
   891 void Method::link_method(methodHandle h_method, TRAPS) {
   892   // If the code cache is full, we may reenter this function for the
   893   // leftover methods that weren't linked.
   894   if (_i2i_entry != NULL) return;
   896   assert(_adapter == NULL, "init'd to NULL" );
   897   assert( _code == NULL, "nothing compiled yet" );
   899   // Setup interpreter entrypoint
   900   assert(this == h_method(), "wrong h_method()" );
   901   address entry = Interpreter::entry_for_method(h_method);
   902   assert(entry != NULL, "interpreter entry must be non-null");
   903   // Sets both _i2i_entry and _from_interpreted_entry
   904   set_interpreter_entry(entry);
   906   // Don't overwrite already registered native entries.
   907   if (is_native() && !has_native_function()) {
   908     set_native_function(
   909       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
   910       !native_bind_event_is_interesting);
   911   }
   913   // Setup compiler entrypoint.  This is made eagerly, so we do not need
   914   // special handling of vtables.  An alternative is to make adapters more
   915   // lazily by calling make_adapter() from from_compiled_entry() for the
   916   // normal calls.  For vtable calls life gets more complicated.  When a
   917   // call-site goes mega-morphic we need adapters in all methods which can be
   918   // called from the vtable.  We need adapters on such methods that get loaded
   919   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
   920   // problem we'll make these lazily later.
   921   (void) make_adapters(h_method, CHECK);
   923   // ONLY USE the h_method now as make_adapter may have blocked
   925 }
   927 address Method::make_adapters(methodHandle mh, TRAPS) {
   928   // Adapters for compiled code are made eagerly here.  They are fairly
   929   // small (generally < 100 bytes) and quick to make (and cached and shared)
   930   // so making them eagerly shouldn't be too expensive.
   931   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
   932   if (adapter == NULL ) {
   933     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "out of space in CodeCache for adapters");
   934   }
   936   mh->set_adapter_entry(adapter);
   937   mh->_from_compiled_entry = adapter->get_c2i_entry();
   938   return adapter->get_c2i_entry();
   939 }
   941 void Method::restore_unshareable_info(TRAPS) {
   942   // Since restore_unshareable_info can be called more than once for a method, don't
   943   // redo any work.   If this field is restored, there is nothing to do.
   944   if (_from_compiled_entry == NULL) {
   945     // restore method's vtable by calling a virtual function
   946     restore_vtable();
   948     methodHandle mh(THREAD, this);
   949     link_method(mh, CHECK);
   950   }
   951 }
   954 // The verified_code_entry() must be called when a invoke is resolved
   955 // on this method.
   957 // It returns the compiled code entry point, after asserting not null.
   958 // This function is called after potential safepoints so that nmethod
   959 // or adapter that it points to is still live and valid.
   960 // This function must not hit a safepoint!
   961 address Method::verified_code_entry() {
   962   debug_only(No_Safepoint_Verifier nsv;)
   963   assert(_from_compiled_entry != NULL, "must be set");
   964   return _from_compiled_entry;
   965 }
   967 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
   968 // (could be racing a deopt).
   969 // Not inline to avoid circular ref.
   970 bool Method::check_code() const {
   971   // cached in a register or local.  There's a race on the value of the field.
   972   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
   973   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
   974 }
   976 // Install compiled code.  Instantly it can execute.
   977 void Method::set_code(methodHandle mh, nmethod *code) {
   978   assert( code, "use clear_code to remove code" );
   979   assert( mh->check_code(), "" );
   981   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
   983   // These writes must happen in this order, because the interpreter will
   984   // directly jump to from_interpreted_entry which jumps to an i2c adapter
   985   // which jumps to _from_compiled_entry.
   986   mh->_code = code;             // Assign before allowing compiled code to exec
   988   int comp_level = code->comp_level();
   989   // In theory there could be a race here. In practice it is unlikely
   990   // and not worth worrying about.
   991   if (comp_level > mh->highest_comp_level()) {
   992     mh->set_highest_comp_level(comp_level);
   993   }
   995   OrderAccess::storestore();
   996 #ifdef SHARK
   997   mh->_from_interpreted_entry = code->insts_begin();
   998 #else //!SHARK
   999   mh->_from_compiled_entry = code->verified_entry_point();
  1000   OrderAccess::storestore();
  1001   // Instantly compiled code can execute.
  1002   if (!mh->is_method_handle_intrinsic())
  1003     mh->_from_interpreted_entry = mh->get_i2c_entry();
  1004 #endif //!SHARK
  1008 bool Method::is_overridden_in(Klass* k) const {
  1009   InstanceKlass* ik = InstanceKlass::cast(k);
  1011   if (ik->is_interface()) return false;
  1013   // If method is an interface, we skip it - except if it
  1014   // is a miranda method
  1015   if (method_holder()->is_interface()) {
  1016     // Check that method is not a miranda method
  1017     if (ik->lookup_method(name(), signature()) == NULL) {
  1018       // No implementation exist - so miranda method
  1019       return false;
  1021     return true;
  1024   assert(ik->is_subclass_of(method_holder()), "should be subklass");
  1025   assert(ik->vtable() != NULL, "vtable should exist");
  1026   if (!has_vtable_index()) {
  1027     return false;
  1028   } else {
  1029     Method* vt_m = ik->method_at_vtable(vtable_index());
  1030     return vt_m != this;
  1035 // give advice about whether this Method* should be cached or not
  1036 bool Method::should_not_be_cached() const {
  1037   if (is_old()) {
  1038     // This method has been redefined. It is either EMCP or obsolete
  1039     // and we don't want to cache it because that would pin the method
  1040     // down and prevent it from being collectible if and when it
  1041     // finishes executing.
  1042     return true;
  1045   // caching this method should be just fine
  1046   return false;
  1050 /**
  1051  *  Returns true if this is one of the specially treated methods for
  1052  *  security related stack walks (like Reflection.getCallerClass).
  1053  */
  1054 bool Method::is_ignored_by_security_stack_walk() const {
  1055   const bool use_new_reflection = JDK_Version::is_gte_jdk14x_version() && UseNewReflection;
  1057   if (intrinsic_id() == vmIntrinsics::_invoke) {
  1058     // This is Method.invoke() -- ignore it
  1059     return true;
  1061   if (use_new_reflection &&
  1062       method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
  1063     // This is an auxilary frame -- ignore it
  1064     return true;
  1066   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
  1067     // This is an internal adapter frame for method handles -- ignore it
  1068     return true;
  1070   return false;
  1074 // Constant pool structure for invoke methods:
  1075 enum {
  1076   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
  1077   _imcp_invoke_signature,       // utf8: (variable Symbol*)
  1078   _imcp_limit
  1079 };
  1081 // Test if this method is an MH adapter frame generated by Java code.
  1082 // Cf. java/lang/invoke/InvokerBytecodeGenerator
  1083 bool Method::is_compiled_lambda_form() const {
  1084   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
  1087 // Test if this method is an internal MH primitive method.
  1088 bool Method::is_method_handle_intrinsic() const {
  1089   vmIntrinsics::ID iid = intrinsic_id();
  1090   return (MethodHandles::is_signature_polymorphic(iid) &&
  1091           MethodHandles::is_signature_polymorphic_intrinsic(iid));
  1094 bool Method::has_member_arg() const {
  1095   vmIntrinsics::ID iid = intrinsic_id();
  1096   return (MethodHandles::is_signature_polymorphic(iid) &&
  1097           MethodHandles::has_member_arg(iid));
  1100 // Make an instance of a signature-polymorphic internal MH primitive.
  1101 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
  1102                                                          Symbol* signature,
  1103                                                          TRAPS) {
  1104   ResourceMark rm;
  1105   methodHandle empty;
  1107   KlassHandle holder = SystemDictionary::MethodHandle_klass();
  1108   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
  1109   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
  1110   if (TraceMethodHandles) {
  1111     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
  1114   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
  1115   name->increment_refcount();
  1116   signature->increment_refcount();
  1118   int cp_length = _imcp_limit;
  1119   ClassLoaderData* loader_data = holder->class_loader_data();
  1120   constantPoolHandle cp;
  1122     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
  1123     cp = constantPoolHandle(THREAD, cp_oop);
  1125   cp->set_pool_holder(InstanceKlass::cast(holder()));
  1126   cp->symbol_at_put(_imcp_invoke_name,       name);
  1127   cp->symbol_at_put(_imcp_invoke_signature,  signature);
  1128   cp->set_has_preresolution();
  1130   // decide on access bits:  public or not?
  1131   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
  1132   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
  1133   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
  1134   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
  1136   methodHandle m;
  1138     InlineTableSizes sizes;
  1139     Method* m_oop = Method::allocate(loader_data, 0,
  1140                                      accessFlags_from(flags_bits), &sizes,
  1141                                      ConstMethod::NORMAL, CHECK_(empty));
  1142     m = methodHandle(THREAD, m_oop);
  1144   m->set_constants(cp());
  1145   m->set_name_index(_imcp_invoke_name);
  1146   m->set_signature_index(_imcp_invoke_signature);
  1147   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
  1148   assert(m->signature() == signature, "");
  1149   ResultTypeFinder rtf(signature);
  1150   m->constMethod()->set_result_type(rtf.type());
  1151   m->compute_size_of_parameters(THREAD);
  1152   m->init_intrinsic_id();
  1153   assert(m->is_method_handle_intrinsic(), "");
  1154 #ifdef ASSERT
  1155   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
  1156   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
  1157   assert(m->intrinsic_id() == iid, "correctly predicted iid");
  1158 #endif //ASSERT
  1160   // Finally, set up its entry points.
  1161   assert(m->can_be_statically_bound(), "");
  1162   m->set_vtable_index(Method::nonvirtual_vtable_index);
  1163   m->link_method(m, CHECK_(empty));
  1165   if (TraceMethodHandles && (Verbose || WizardMode))
  1166     m->print_on(tty);
  1168   return m;
  1171 Klass* Method::check_non_bcp_klass(Klass* klass) {
  1172   if (klass != NULL && klass->class_loader() != NULL) {
  1173     if (klass->oop_is_objArray())
  1174       klass = ObjArrayKlass::cast(klass)->bottom_klass();
  1175     return klass;
  1177   return NULL;
  1181 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
  1182                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
  1183   // Code below does not work for native methods - they should never get rewritten anyway
  1184   assert(!m->is_native(), "cannot rewrite native methods");
  1185   // Allocate new Method*
  1186   AccessFlags flags = m->access_flags();
  1188   ConstMethod* cm = m->constMethod();
  1189   int checked_exceptions_len = cm->checked_exceptions_length();
  1190   int localvariable_len = cm->localvariable_table_length();
  1191   int exception_table_len = cm->exception_table_length();
  1192   int method_parameters_len = cm->method_parameters_length();
  1193   int method_annotations_len = cm->method_annotations_length();
  1194   int parameter_annotations_len = cm->parameter_annotations_length();
  1195   int type_annotations_len = cm->type_annotations_length();
  1196   int default_annotations_len = cm->default_annotations_length();
  1198   InlineTableSizes sizes(
  1199       localvariable_len,
  1200       new_compressed_linenumber_size,
  1201       exception_table_len,
  1202       checked_exceptions_len,
  1203       method_parameters_len,
  1204       cm->generic_signature_index(),
  1205       method_annotations_len,
  1206       parameter_annotations_len,
  1207       type_annotations_len,
  1208       default_annotations_len,
  1209       0);
  1211   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
  1212   Method* newm_oop = Method::allocate(loader_data,
  1213                                       new_code_length,
  1214                                       flags,
  1215                                       &sizes,
  1216                                       m->method_type(),
  1217                                       CHECK_(methodHandle()));
  1218   methodHandle newm (THREAD, newm_oop);
  1219   int new_method_size = newm->method_size();
  1221   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
  1222   ConstMethod* newcm = newm->constMethod();
  1223   int new_const_method_size = newm->constMethod()->size();
  1225   memcpy(newm(), m(), sizeof(Method));
  1227   // Create shallow copy of ConstMethod.
  1228   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
  1230   // Reset correct method/const method, method size, and parameter info
  1231   newm->set_constMethod(newcm);
  1232   newm->constMethod()->set_code_size(new_code_length);
  1233   newm->constMethod()->set_constMethod_size(new_const_method_size);
  1234   newm->set_method_size(new_method_size);
  1235   assert(newm->code_size() == new_code_length, "check");
  1236   assert(newm->method_parameters_length() == method_parameters_len, "check");
  1237   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
  1238   assert(newm->exception_table_length() == exception_table_len, "check");
  1239   assert(newm->localvariable_table_length() == localvariable_len, "check");
  1240   // Copy new byte codes
  1241   memcpy(newm->code_base(), new_code, new_code_length);
  1242   // Copy line number table
  1243   if (new_compressed_linenumber_size > 0) {
  1244     memcpy(newm->compressed_linenumber_table(),
  1245            new_compressed_linenumber_table,
  1246            new_compressed_linenumber_size);
  1248   // Copy method_parameters
  1249   if (method_parameters_len > 0) {
  1250     memcpy(newm->method_parameters_start(),
  1251            m->method_parameters_start(),
  1252            method_parameters_len * sizeof(MethodParametersElement));
  1254   // Copy checked_exceptions
  1255   if (checked_exceptions_len > 0) {
  1256     memcpy(newm->checked_exceptions_start(),
  1257            m->checked_exceptions_start(),
  1258            checked_exceptions_len * sizeof(CheckedExceptionElement));
  1260   // Copy exception table
  1261   if (exception_table_len > 0) {
  1262     memcpy(newm->exception_table_start(),
  1263            m->exception_table_start(),
  1264            exception_table_len * sizeof(ExceptionTableElement));
  1266   // Copy local variable number table
  1267   if (localvariable_len > 0) {
  1268     memcpy(newm->localvariable_table_start(),
  1269            m->localvariable_table_start(),
  1270            localvariable_len * sizeof(LocalVariableTableElement));
  1272   // Copy stackmap table
  1273   if (m->has_stackmap_table()) {
  1274     int code_attribute_length = m->stackmap_data()->length();
  1275     Array<u1>* stackmap_data =
  1276       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
  1277     memcpy((void*)stackmap_data->adr_at(0),
  1278            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
  1279     newm->set_stackmap_data(stackmap_data);
  1282   // copy annotations over to new method
  1283   newcm->copy_annotations_from(cm);
  1284   return newm;
  1287 vmSymbols::SID Method::klass_id_for_intrinsics(Klass* holder) {
  1288   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
  1289   // because we are not loading from core libraries
  1290   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
  1291   // which does not use the class default class loader so we check for its loader here
  1292   InstanceKlass* ik = InstanceKlass::cast(holder);
  1293   if ((ik->class_loader() != NULL) && !SystemDictionary::is_ext_class_loader(ik->class_loader())) {
  1294     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
  1297   // see if the klass name is well-known:
  1298   Symbol* klass_name = ik->name();
  1299   return vmSymbols::find_sid(klass_name);
  1302 void Method::init_intrinsic_id() {
  1303   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
  1304   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
  1305   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
  1306   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
  1308   // the klass name is well-known:
  1309   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
  1310   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
  1312   // ditto for method and signature:
  1313   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
  1314   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
  1315       && name_id == vmSymbols::NO_SID)
  1316     return;
  1317   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
  1318   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
  1319       && sig_id == vmSymbols::NO_SID)  return;
  1320   jshort flags = access_flags().as_short();
  1322   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
  1323   if (id != vmIntrinsics::_none) {
  1324     set_intrinsic_id(id);
  1325     return;
  1328   // A few slightly irregular cases:
  1329   switch (klass_id) {
  1330   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
  1331     // Second chance: check in regular Math.
  1332     switch (name_id) {
  1333     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
  1334     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
  1335     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
  1336       // pretend it is the corresponding method in the non-strict class:
  1337       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
  1338       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
  1339       break;
  1341     break;
  1343   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*.
  1344   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
  1345     if (!is_native())  break;
  1346     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
  1347     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
  1348       id = vmIntrinsics::_none;
  1349     break;
  1352   if (id != vmIntrinsics::_none) {
  1353     // Set up its iid.  It is an alias method.
  1354     set_intrinsic_id(id);
  1355     return;
  1359 // These two methods are static since a GC may move the Method
  1360 bool Method::load_signature_classes(methodHandle m, TRAPS) {
  1361   if (THREAD->is_Compiler_thread()) {
  1362     // There is nothing useful this routine can do from within the Compile thread.
  1363     // Hopefully, the signature contains only well-known classes.
  1364     // We could scan for this and return true/false, but the caller won't care.
  1365     return false;
  1367   bool sig_is_loaded = true;
  1368   Handle class_loader(THREAD, m->method_holder()->class_loader());
  1369   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
  1370   ResourceMark rm(THREAD);
  1371   Symbol*  signature = m->signature();
  1372   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
  1373     if (ss.is_object()) {
  1374       Symbol* sym = ss.as_symbol(CHECK_(false));
  1375       Symbol*  name  = sym;
  1376       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
  1377                                              protection_domain, THREAD);
  1378       // We are loading classes eagerly. If a ClassNotFoundException or
  1379       // a LinkageError was generated, be sure to ignore it.
  1380       if (HAS_PENDING_EXCEPTION) {
  1381         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
  1382             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
  1383           CLEAR_PENDING_EXCEPTION;
  1384         } else {
  1385           return false;
  1388       if( klass == NULL) { sig_is_loaded = false; }
  1391   return sig_is_loaded;
  1394 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
  1395   Handle class_loader(THREAD, m->method_holder()->class_loader());
  1396   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
  1397   ResourceMark rm(THREAD);
  1398   Symbol*  signature = m->signature();
  1399   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
  1400     if (ss.type() == T_OBJECT) {
  1401       Symbol* name = ss.as_symbol_or_null();
  1402       if (name == NULL) return true;
  1403       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
  1404       if (klass == NULL) return true;
  1407   return false;
  1410 // Exposed so field engineers can debug VM
  1411 void Method::print_short_name(outputStream* st) {
  1412   ResourceMark rm;
  1413 #ifdef PRODUCT
  1414   st->print(" %s::", method_holder()->external_name());
  1415 #else
  1416   st->print(" %s::", method_holder()->internal_name());
  1417 #endif
  1418   name()->print_symbol_on(st);
  1419   if (WizardMode) signature()->print_symbol_on(st);
  1420   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
  1421     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
  1424 // Comparer for sorting an object array containing
  1425 // Method*s.
  1426 static int method_comparator(Method* a, Method* b) {
  1427   return a->name()->fast_compare(b->name());
  1430 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
  1431 // default_methods also uses this without the ordering for fast find_method
  1432 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
  1433   int length = methods->length();
  1434   if (length > 1) {
  1436       No_Safepoint_Verifier nsv;
  1437       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
  1439     // Reset method ordering
  1440     if (set_idnums) {
  1441       for (int i = 0; i < length; i++) {
  1442         Method* m = methods->at(i);
  1443         m->set_method_idnum(i);
  1444         m->set_orig_method_idnum(i);
  1450 //-----------------------------------------------------------------------------------
  1451 // Non-product code unless JVM/TI needs it
  1453 #if !defined(PRODUCT) || INCLUDE_JVMTI
  1454 class SignatureTypePrinter : public SignatureTypeNames {
  1455  private:
  1456   outputStream* _st;
  1457   bool _use_separator;
  1459   void type_name(const char* name) {
  1460     if (_use_separator) _st->print(", ");
  1461     _st->print("%s", name);
  1462     _use_separator = true;
  1465  public:
  1466   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
  1467     _st = st;
  1468     _use_separator = false;
  1471   void print_parameters()              { _use_separator = false; iterate_parameters(); }
  1472   void print_returntype()              { _use_separator = false; iterate_returntype(); }
  1473 };
  1476 void Method::print_name(outputStream* st) {
  1477   Thread *thread = Thread::current();
  1478   ResourceMark rm(thread);
  1479   SignatureTypePrinter sig(signature(), st);
  1480   st->print("%s ", is_static() ? "static" : "virtual");
  1481   sig.print_returntype();
  1482   st->print(" %s.", method_holder()->internal_name());
  1483   name()->print_symbol_on(st);
  1484   st->print("(");
  1485   sig.print_parameters();
  1486   st->print(")");
  1488 #endif // !PRODUCT || INCLUDE_JVMTI
  1491 //-----------------------------------------------------------------------------------
  1492 // Non-product code
  1494 #ifndef PRODUCT
  1495 void Method::print_codes_on(outputStream* st) const {
  1496   print_codes_on(0, code_size(), st);
  1499 void Method::print_codes_on(int from, int to, outputStream* st) const {
  1500   Thread *thread = Thread::current();
  1501   ResourceMark rm(thread);
  1502   methodHandle mh (thread, (Method*)this);
  1503   BytecodeStream s(mh);
  1504   s.set_interval(from, to);
  1505   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
  1506   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
  1508 #endif // not PRODUCT
  1511 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
  1512 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
  1513 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
  1514 // as end-of-stream terminator.
  1516 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
  1517   // bci and line number does not compress into single byte.
  1518   // Write out escape character and use regular compression for bci and line number.
  1519   write_byte((jubyte)0xFF);
  1520   write_signed_int(bci_delta);
  1521   write_signed_int(line_delta);
  1524 // See comment in method.hpp which explains why this exists.
  1525 #if defined(_M_AMD64) && _MSC_VER >= 1400
  1526 #pragma optimize("", off)
  1527 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
  1528   write_pair_inline(bci, line);
  1530 #pragma optimize("", on)
  1531 #endif
  1533 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
  1534   _bci = 0;
  1535   _line = 0;
  1536 };
  1539 bool CompressedLineNumberReadStream::read_pair() {
  1540   jubyte next = read_byte();
  1541   // Check for terminator
  1542   if (next == 0) return false;
  1543   if (next == 0xFF) {
  1544     // Escape character, regular compression used
  1545     _bci  += read_signed_int();
  1546     _line += read_signed_int();
  1547   } else {
  1548     // Single byte compression used
  1549     _bci  += next >> 3;
  1550     _line += next & 0x7;
  1552   return true;
  1556 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
  1557   BreakpointInfo* bp = method_holder()->breakpoints();
  1558   for (; bp != NULL; bp = bp->next()) {
  1559     if (bp->match(this, bci)) {
  1560       return bp->orig_bytecode();
  1564     ResourceMark rm;
  1565     fatal(err_msg("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci));
  1567   return Bytecodes::_shouldnotreachhere;
  1570 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
  1571   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
  1572   BreakpointInfo* bp = method_holder()->breakpoints();
  1573   for (; bp != NULL; bp = bp->next()) {
  1574     if (bp->match(this, bci)) {
  1575       bp->set_orig_bytecode(code);
  1576       // and continue, in case there is more than one
  1581 void Method::set_breakpoint(int bci) {
  1582   InstanceKlass* ik = method_holder();
  1583   BreakpointInfo *bp = new BreakpointInfo(this, bci);
  1584   bp->set_next(ik->breakpoints());
  1585   ik->set_breakpoints(bp);
  1586   // do this last:
  1587   bp->set(this);
  1590 static void clear_matches(Method* m, int bci) {
  1591   InstanceKlass* ik = m->method_holder();
  1592   BreakpointInfo* prev_bp = NULL;
  1593   BreakpointInfo* next_bp;
  1594   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
  1595     next_bp = bp->next();
  1596     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
  1597     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
  1598       // do this first:
  1599       bp->clear(m);
  1600       // unhook it
  1601       if (prev_bp != NULL)
  1602         prev_bp->set_next(next_bp);
  1603       else
  1604         ik->set_breakpoints(next_bp);
  1605       delete bp;
  1606       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
  1607       // at same location. So we have multiple matching (method_index and bci)
  1608       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
  1609       // breakpoint for clear_breakpoint request and keep all other method versions
  1610       // BreakpointInfo for future clear_breakpoint request.
  1611       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
  1612       // which is being called when class is unloaded. We delete all the Breakpoint
  1613       // information for all versions of method. We may not correctly restore the original
  1614       // bytecode in all method versions, but that is ok. Because the class is being unloaded
  1615       // so these methods won't be used anymore.
  1616       if (bci >= 0) {
  1617         break;
  1619     } else {
  1620       // This one is a keeper.
  1621       prev_bp = bp;
  1626 void Method::clear_breakpoint(int bci) {
  1627   assert(bci >= 0, "");
  1628   clear_matches(this, bci);
  1631 void Method::clear_all_breakpoints() {
  1632   clear_matches(this, -1);
  1636 int Method::invocation_count() {
  1637   MethodCounters *mcs = method_counters();
  1638   if (TieredCompilation) {
  1639     MethodData* const mdo = method_data();
  1640     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
  1641         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
  1642       return InvocationCounter::count_limit;
  1643     } else {
  1644       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
  1645              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
  1647   } else {
  1648     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
  1652 int Method::backedge_count() {
  1653   MethodCounters *mcs = method_counters();
  1654   if (TieredCompilation) {
  1655     MethodData* const mdo = method_data();
  1656     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
  1657         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
  1658       return InvocationCounter::count_limit;
  1659     } else {
  1660       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
  1661              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
  1663   } else {
  1664     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
  1668 int Method::highest_comp_level() const {
  1669   const MethodCounters* mcs = method_counters();
  1670   if (mcs != NULL) {
  1671     return mcs->highest_comp_level();
  1672   } else {
  1673     return CompLevel_none;
  1677 int Method::highest_osr_comp_level() const {
  1678   const MethodCounters* mcs = method_counters();
  1679   if (mcs != NULL) {
  1680     return mcs->highest_osr_comp_level();
  1681   } else {
  1682     return CompLevel_none;
  1686 void Method::set_highest_comp_level(int level) {
  1687   MethodCounters* mcs = method_counters();
  1688   if (mcs != NULL) {
  1689     mcs->set_highest_comp_level(level);
  1693 void Method::set_highest_osr_comp_level(int level) {
  1694   MethodCounters* mcs = method_counters();
  1695   if (mcs != NULL) {
  1696     mcs->set_highest_osr_comp_level(level);
  1700 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
  1701   _bci = bci;
  1702   _name_index = m->name_index();
  1703   _signature_index = m->signature_index();
  1704   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
  1705   if (_orig_bytecode == Bytecodes::_breakpoint)
  1706     _orig_bytecode = m->orig_bytecode_at(_bci);
  1707   _next = NULL;
  1710 void BreakpointInfo::set(Method* method) {
  1711 #ifdef ASSERT
  1713     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
  1714     if (code == Bytecodes::_breakpoint)
  1715       code = method->orig_bytecode_at(_bci);
  1716     assert(orig_bytecode() == code, "original bytecode must be the same");
  1718 #endif
  1719   Thread *thread = Thread::current();
  1720   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
  1721   method->incr_number_of_breakpoints(thread);
  1722   SystemDictionary::notice_modification();
  1724     // Deoptimize all dependents on this method
  1725     HandleMark hm(thread);
  1726     methodHandle mh(thread, method);
  1727     Universe::flush_dependents_on_method(mh);
  1731 void BreakpointInfo::clear(Method* method) {
  1732   *method->bcp_from(_bci) = orig_bytecode();
  1733   assert(method->number_of_breakpoints() > 0, "must not go negative");
  1734   method->decr_number_of_breakpoints(Thread::current());
  1737 // jmethodID handling
  1739 // This is a block allocating object, sort of like JNIHandleBlock, only a
  1740 // lot simpler.  There aren't many of these, they aren't long, they are rarely
  1741 // deleted and so we can do some suboptimal things.
  1742 // It's allocated on the CHeap because once we allocate a jmethodID, we can
  1743 // never get rid of it.
  1744 // It would be nice to be able to parameterize the number of methods for
  1745 // the null_class_loader but then we'd have to turn this and ClassLoaderData
  1746 // into templates.
  1748 // I feel like this brain dead class should exist somewhere in the STL
  1750 class JNIMethodBlock : public CHeapObj<mtClass> {
  1751   enum { number_of_methods = 8 };
  1753   Method*         _methods[number_of_methods];
  1754   int             _top;
  1755   JNIMethodBlock* _next;
  1756  public:
  1757   static Method* const _free_method;
  1759   JNIMethodBlock() : _next(NULL), _top(0) {
  1760     for (int i = 0; i< number_of_methods; i++) _methods[i] = _free_method;
  1763   Method** add_method(Method* m) {
  1764     if (_top < number_of_methods) {
  1765       // top points to the next free entry.
  1766       int i = _top;
  1767       _methods[i] = m;
  1768       _top++;
  1769       return &_methods[i];
  1770     } else if (_top == number_of_methods) {
  1771       // if the next free entry ran off the block see if there's a free entry
  1772       for (int i = 0; i< number_of_methods; i++) {
  1773         if (_methods[i] == _free_method) {
  1774           _methods[i] = m;
  1775           return &_methods[i];
  1778       // Only check each block once for frees.  They're very unlikely.
  1779       // Increment top past the end of the block.
  1780       _top++;
  1782     // need to allocate a next block.
  1783     if (_next == NULL) {
  1784       _next = new JNIMethodBlock();
  1786     return _next->add_method(m);
  1789   bool contains(Method** m) {
  1790     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
  1791       for (int i = 0; i< number_of_methods; i++) {
  1792         if (&(b->_methods[i]) == m) {
  1793           return true;
  1797     return false;  // not found
  1800   // Doesn't really destroy it, just marks it as free so it can be reused.
  1801   void destroy_method(Method** m) {
  1802 #ifdef ASSERT
  1803     assert(contains(m), "should be a methodID");
  1804 #endif // ASSERT
  1805     *m = _free_method;
  1807   void clear_method(Method* m) {
  1808     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
  1809       for (int i = 0; i < number_of_methods; i++) {
  1810         if (b->_methods[i] == m) {
  1811           b->_methods[i] = NULL;
  1812           return;
  1816     // not found
  1819   // During class unloading the methods are cleared, which is different
  1820   // than freed.
  1821   void clear_all_methods() {
  1822     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
  1823       for (int i = 0; i< number_of_methods; i++) {
  1824         b->_methods[i] = NULL;
  1828 #ifndef PRODUCT
  1829   int count_methods() {
  1830     // count all allocated methods
  1831     int count = 0;
  1832     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
  1833       for (int i = 0; i< number_of_methods; i++) {
  1834         if (b->_methods[i] != _free_method) count++;
  1837     return count;
  1839 #endif // PRODUCT
  1840 };
  1842 // Something that can't be mistaken for an address or a markOop
  1843 Method* const JNIMethodBlock::_free_method = (Method*)55;
  1845 // Add a method id to the jmethod_ids
  1846 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
  1847   ClassLoaderData* cld = loader_data;
  1849   if (!SafepointSynchronize::is_at_safepoint()) {
  1850     // Have to add jmethod_ids() to class loader data thread-safely.
  1851     // Also have to add the method to the list safely, which the cld lock
  1852     // protects as well.
  1853     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
  1854     if (cld->jmethod_ids() == NULL) {
  1855       cld->set_jmethod_ids(new JNIMethodBlock());
  1857     // jmethodID is a pointer to Method*
  1858     return (jmethodID)cld->jmethod_ids()->add_method(m);
  1859   } else {
  1860     // At safepoint, we are single threaded and can set this.
  1861     if (cld->jmethod_ids() == NULL) {
  1862       cld->set_jmethod_ids(new JNIMethodBlock());
  1864     // jmethodID is a pointer to Method*
  1865     return (jmethodID)cld->jmethod_ids()->add_method(m);
  1869 // Mark a jmethodID as free.  This is called when there is a data race in
  1870 // InstanceKlass while creating the jmethodID cache.
  1871 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
  1872   ClassLoaderData* cld = loader_data;
  1873   Method** ptr = (Method**)m;
  1874   assert(cld->jmethod_ids() != NULL, "should have method handles");
  1875   cld->jmethod_ids()->destroy_method(ptr);
  1878 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
  1879   // Can't assert the method_holder is the same because the new method has the
  1880   // scratch method holder.
  1881   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
  1882            == new_method->method_holder()->class_loader(),
  1883          "changing to a different class loader");
  1884   // Just change the method in place, jmethodID pointer doesn't change.
  1885   *((Method**)jmid) = new_method;
  1888 bool Method::is_method_id(jmethodID mid) {
  1889   Method* m = resolve_jmethod_id(mid);
  1890   if (m == NULL) {
  1891     return false;
  1893   InstanceKlass* ik = m->method_holder();
  1894   if (ik == NULL) {
  1895     return false;
  1897   ClassLoaderData* cld = ik->class_loader_data();
  1898   if (cld->jmethod_ids() == NULL) return false;
  1899   return (cld->jmethod_ids()->contains((Method**)mid));
  1902 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
  1903   if (mid == NULL) return NULL;
  1904   if (!Method::is_method_id(mid)) {
  1905     return NULL;
  1907   Method* o = resolve_jmethod_id(mid);
  1908   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
  1909     return NULL;
  1911   return o;
  1912 };
  1914 void Method::set_on_stack(const bool value) {
  1915   // Set both the method itself and its constant pool.  The constant pool
  1916   // on stack means some method referring to it is also on the stack.
  1917   constants()->set_on_stack(value);
  1919   bool succeeded = _access_flags.set_on_stack(value);
  1920   if (value && succeeded) {
  1921     MetadataOnStackMark::record(this, Thread::current());
  1925 void Method::clear_jmethod_id(ClassLoaderData* loader_data) {
  1926   loader_data->jmethod_ids()->clear_method(this);
  1929 // Called when the class loader is unloaded to make all methods weak.
  1930 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
  1931   loader_data->jmethod_ids()->clear_all_methods();
  1934 bool Method::has_method_vptr(const void* ptr) {
  1935   Method m;
  1936   // This assumes that the vtbl pointer is the first word of a C++ object.
  1937   // This assumption is also in universe.cpp patch_klass_vtble
  1938   void* vtbl2 = dereference_vptr((const void*)&m);
  1939   void* this_vtbl = dereference_vptr(ptr);
  1940   return vtbl2 == this_vtbl;
  1943 // Check that this pointer is valid by checking that the vtbl pointer matches
  1944 bool Method::is_valid_method() const {
  1945   if (this == NULL) {
  1946     return false;
  1947   } else if (!is_metaspace_object()) {
  1948     return false;
  1949   } else {
  1950     return has_method_vptr((const void*)this);
  1954 #ifndef PRODUCT
  1955 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
  1956   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
  1958 #endif // PRODUCT
  1961 // Printing
  1963 #ifndef PRODUCT
  1965 void Method::print_on(outputStream* st) const {
  1966   ResourceMark rm;
  1967   assert(is_method(), "must be method");
  1968   st->print_cr("%s", internal_name());
  1969   // get the effect of PrintOopAddress, always, for methods:
  1970   st->print_cr(" - this oop:          "INTPTR_FORMAT, (intptr_t)this);
  1971   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
  1972   st->print   (" - constants:         "INTPTR_FORMAT" ", (address)constants());
  1973   constants()->print_value_on(st); st->cr();
  1974   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
  1975   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
  1976   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
  1977   st->print_cr(" - max stack:         %d",   max_stack());
  1978   st->print_cr(" - max locals:        %d",   max_locals());
  1979   st->print_cr(" - size of params:    %d",   size_of_parameters());
  1980   st->print_cr(" - method size:       %d",   method_size());
  1981   if (intrinsic_id() != vmIntrinsics::_none)
  1982     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
  1983   if (highest_comp_level() != CompLevel_none)
  1984     st->print_cr(" - highest level:     %d", highest_comp_level());
  1985   st->print_cr(" - vtable index:      %d",   _vtable_index);
  1986   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, interpreter_entry());
  1987   st->print(   " - adapters:          ");
  1988   AdapterHandlerEntry* a = ((Method*)this)->adapter();
  1989   if (a == NULL)
  1990     st->print_cr(INTPTR_FORMAT, a);
  1991   else
  1992     a->print_adapter_on(st);
  1993   st->print_cr(" - compiled entry     " INTPTR_FORMAT, from_compiled_entry());
  1994   st->print_cr(" - code size:         %d",   code_size());
  1995   if (code_size() != 0) {
  1996     st->print_cr(" - code start:        " INTPTR_FORMAT, code_base());
  1997     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, code_base() + code_size());
  1999   if (method_data() != NULL) {
  2000     st->print_cr(" - method data:       " INTPTR_FORMAT, (address)method_data());
  2002   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
  2003   if (checked_exceptions_length() > 0) {
  2004     CheckedExceptionElement* table = checked_exceptions_start();
  2005     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, table);
  2006     if (Verbose) {
  2007       for (int i = 0; i < checked_exceptions_length(); i++) {
  2008         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
  2012   if (has_linenumber_table()) {
  2013     u_char* table = compressed_linenumber_table();
  2014     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, table);
  2015     if (Verbose) {
  2016       CompressedLineNumberReadStream stream(table);
  2017       while (stream.read_pair()) {
  2018         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
  2022   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
  2023   if (localvariable_table_length() > 0) {
  2024     LocalVariableTableElement* table = localvariable_table_start();
  2025     st->print_cr(" - localvar start:    " INTPTR_FORMAT, table);
  2026     if (Verbose) {
  2027       for (int i = 0; i < localvariable_table_length(); i++) {
  2028         int bci = table[i].start_bci;
  2029         int len = table[i].length;
  2030         const char* name = constants()->printable_name_at(table[i].name_cp_index);
  2031         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
  2032         int slot = table[i].slot;
  2033         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
  2037   if (code() != NULL) {
  2038     st->print   (" - compiled code: ");
  2039     code()->print_value_on(st);
  2041   if (is_native()) {
  2042     st->print_cr(" - native function:   " INTPTR_FORMAT, native_function());
  2043     st->print_cr(" - signature handler: " INTPTR_FORMAT, signature_handler());
  2047 #endif //PRODUCT
  2049 void Method::print_value_on(outputStream* st) const {
  2050   assert(is_method(), "must be method");
  2051   st->print("%s", internal_name());
  2052   print_address_on(st);
  2053   st->print(" ");
  2054   name()->print_value_on(st);
  2055   st->print(" ");
  2056   signature()->print_value_on(st);
  2057   st->print(" in ");
  2058   method_holder()->print_value_on(st);
  2059   if (WizardMode) st->print("#%d", _vtable_index);
  2060   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
  2061   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
  2064 #if INCLUDE_SERVICES
  2065 // Size Statistics
  2066 void Method::collect_statistics(KlassSizeStats *sz) const {
  2067   int mysize = sz->count(this);
  2068   sz->_method_bytes += mysize;
  2069   sz->_method_all_bytes += mysize;
  2070   sz->_rw_bytes += mysize;
  2072   if (constMethod()) {
  2073     constMethod()->collect_statistics(sz);
  2075   if (method_data()) {
  2076     method_data()->collect_statistics(sz);
  2079 #endif // INCLUDE_SERVICES
  2081 // Verification
  2083 void Method::verify_on(outputStream* st) {
  2084   guarantee(is_method(), "object must be method");
  2085   guarantee(constants()->is_constantPool(), "should be constant pool");
  2086   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
  2087   MethodData* md = method_data();
  2088   guarantee(md == NULL ||
  2089       md->is_methodData(), "should be method data");

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