1 /*

     2  * Copyright (c) 2008, 2017, 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/javaClasses.inline.hpp"

    27 #include "classfile/stringTable.hpp"

    28 #include "code/codeCache.hpp"

    29 #include "code/dependencyContext.hpp"

    30 #include "compiler/compileBroker.hpp"

    31 #include "interpreter/interpreter.hpp"

    32 #include "interpreter/oopMapCache.hpp"

    33 #include "interpreter/linkResolver.hpp"

    34 #include "memory/allocation.inline.hpp"

    35 #include "memory/oopFactory.hpp"

    36 #include "memory/resourceArea.hpp"

    37 #include "oops/objArrayOop.inline.hpp"

    38 #include "oops/oop.inline.hpp"

    39 #include "prims/methodHandles.hpp"

    40 #include "runtime/compilationPolicy.hpp"

    41 #include "runtime/javaCalls.hpp"

    42 #include "runtime/timerTrace.hpp"

    43 #include "runtime/reflection.hpp"

    44 #include "runtime/signature.hpp"

    45 #include "runtime/stubRoutines.hpp"

    46 #include "utilities/exceptions.hpp"

    47 

    48 

    49 /*

    50  * JSR 292 reference implementation: method handles

    51  * The JDK 7 reference implementation represented method handle

    52  * combinations as chains.  Each link in the chain had a "vmentry"

    53  * field which pointed at a bit of assembly code which performed

    54  * one transformation before dispatching to the next link in the chain.

    55  *

    56  * The current reference implementation pushes almost all code generation

    57  * responsibility to (trusted) Java code.  A method handle contains a

    58  * pointer to its "LambdaForm", which embodies all details of the method

    59  * handle's behavior.  The LambdaForm is a normal Java object, managed

    60  * by a runtime coded in Java.

    61  */

    62 

    63 bool MethodHandles::_enabled = false; // set true after successful native linkage

    64 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;

    65 

    66 /**

    67  * Generates method handle adapters. Returns 'false' if memory allocation

    68  * failed and true otherwise.

    69  */

    70 void MethodHandles::generate_adapters() {

    71   assert(SystemDictionary::MethodHandle_klass() != NULL, "should be present");

    72   assert(_adapter_code == NULL, "generate only once");

    73 

    74   ResourceMark rm;

    75   TraceTime timer("MethodHandles adapters generation", TRACETIME_LOG(Info, startuptime));

    76   _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);

    77   CodeBuffer code(_adapter_code);

    78   MethodHandlesAdapterGenerator g(&code);

    79   g.generate();

    80   code.log_section_sizes("MethodHandlesAdapterBlob");

    81 }

    82 

    83 //------------------------------------------------------------------------------

    84 // MethodHandlesAdapterGenerator::generate

    85 //

    86 void MethodHandlesAdapterGenerator::generate() {

    87   // Generate generic method handle adapters.

    88   // Generate interpreter entries

    89   for (Interpreter::MethodKind mk = Interpreter::method_handle_invoke_FIRST;

    90        mk <= Interpreter::method_handle_invoke_LAST;

    91        mk = Interpreter::MethodKind(1 + (int)mk)) {

    92     vmIntrinsics::ID iid = Interpreter::method_handle_intrinsic(mk);

    93     StubCodeMark mark(this, "MethodHandle::interpreter_entry", vmIntrinsics::name_at(iid));

    94     address entry = MethodHandles::generate_method_handle_interpreter_entry(_masm, iid);

    95     if (entry != NULL) {

    96       Interpreter::set_entry_for_kind(mk, entry);

    97     }

    98     // If the entry is not set, it will throw AbstractMethodError.

    99   }

   100 }

   101 

   102 void MethodHandles::set_enabled(bool z) {

   103   if (_enabled != z) {

   104     guarantee(z, "can only enable once");

   105     _enabled = z;

   106   }

   107 }

   108 

   109 // MemberName support

   110 

   111 // import java_lang_invoke_MemberName.*

   112 enum {

   113   IS_METHOD            = java_lang_invoke_MemberName::MN_IS_METHOD,

   114   IS_CONSTRUCTOR       = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,

   115   IS_FIELD             = java_lang_invoke_MemberName::MN_IS_FIELD,

   116   IS_TYPE              = java_lang_invoke_MemberName::MN_IS_TYPE,

   117   CALLER_SENSITIVE     = java_lang_invoke_MemberName::MN_CALLER_SENSITIVE,

   118   REFERENCE_KIND_SHIFT = java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT,

   119   REFERENCE_KIND_MASK  = java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,

   120   SEARCH_SUPERCLASSES  = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,

   121   SEARCH_INTERFACES    = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,

   122   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE

   123 };

   124 

   125 oop MethodHandles::init_MemberName(Handle mname, Handle target, TRAPS) {

   126   // This method is used from java.lang.invoke.MemberName constructors.

   127   // It fills in the new MemberName from a java.lang.reflect.Member.

   128   Thread* thread = Thread::current();

   129   oop target_oop = target();

   130   Klass* target_klass = target_oop->klass();

   131   if (target_klass == SystemDictionary::reflect_Field_klass()) {

   132     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()

   133     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()

   134     Klass* k = java_lang_Class::as_Klass(clazz);

   135     if (k != NULL && k->is_instance_klass()) {

   136       fieldDescriptor fd(InstanceKlass::cast(k), slot);

   137       oop mname2 = init_field_MemberName(mname, fd);

   138       if (mname2 != NULL) {

   139         // Since we have the reified name and type handy, add them to the result.

   140         if (java_lang_invoke_MemberName::name(mname2) == NULL)

   141           java_lang_invoke_MemberName::set_name(mname2, java_lang_reflect_Field::name(target_oop));

   142         if (java_lang_invoke_MemberName::type(mname2) == NULL)

   143           java_lang_invoke_MemberName::set_type(mname2, java_lang_reflect_Field::type(target_oop));

   144       }

   145       return mname2;

   146     }

   147   } else if (target_klass == SystemDictionary::reflect_Method_klass()) {

   148     oop clazz  = java_lang_reflect_Method::clazz(target_oop);

   149     int slot   = java_lang_reflect_Method::slot(target_oop);

   150     Klass* k = java_lang_Class::as_Klass(clazz);

   151     if (k != NULL && k->is_instance_klass()) {

   152       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);

   153       if (m == NULL || is_signature_polymorphic(m->intrinsic_id()))

   154         return NULL;            // do not resolve unless there is a concrete signature

   155       CallInfo info(m, k, CHECK_NULL);

   156       return init_method_MemberName(mname, info);

   157     }

   158   } else if (target_klass == SystemDictionary::reflect_Constructor_klass()) {

   159     oop clazz  = java_lang_reflect_Constructor::clazz(target_oop);

   160     int slot   = java_lang_reflect_Constructor::slot(target_oop);

   161     Klass* k = java_lang_Class::as_Klass(clazz);

   162     if (k != NULL && k->is_instance_klass()) {

   163       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);

   164       if (m == NULL)  return NULL;

   165       CallInfo info(m, k, CHECK_NULL);

   166       return init_method_MemberName(mname, info);

   167     }

   168   }

   169   return NULL;

   170 }

   171 

   172 oop MethodHandles::init_method_MemberName(Handle mname, CallInfo& info) {

   173   assert(info.resolved_appendix().is_null(), "only normal methods here");

   174   methodHandle m = info.resolved_method();

   175   assert(m.not_null(), "null method handle");

   176   Klass* m_klass = m->method_holder();

   177   assert(m_klass != NULL, "null holder for method handle");

   178   int flags = (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS );

   179   int vmindex = Method::invalid_vtable_index;

   180 

   181   switch (info.call_kind()) {

   182   case CallInfo::itable_call:

   183     vmindex = info.itable_index();

   184     // More importantly, the itable index only works with the method holder.

   185     assert(m_klass->verify_itable_index(vmindex), "");

   186     flags |= IS_METHOD | (JVM_REF_invokeInterface << REFERENCE_KIND_SHIFT);

   187     if (TraceInvokeDynamic) {

   188       ttyLocker ttyl;

   189       ResourceMark rm;

   190       tty->print_cr("memberName: invokeinterface method_holder::method: %s, itableindex: %d, access_flags:",

   191             Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),

   192             vmindex);

   193        m->access_flags().print_on(tty);

   194        if (!m->is_abstract()) {

   195          tty->print("default");

   196        }

   197        tty->cr();

   198     }

   199     break;

   200 

   201   case CallInfo::vtable_call:

   202     vmindex = info.vtable_index();

   203     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);

   204     assert(info.resolved_klass()->is_subtype_of(m_klass), "virtual call must be type-safe");

   205     if (m_klass->is_interface()) {

   206       // This is a vtable call to an interface method (abstract "miranda method" or default method).

   207       // The vtable index is meaningless without a class (not interface) receiver type, so get one.

   208       // (LinkResolver should help us figure this out.)

   209       Klass* m_klass_non_interface = info.resolved_klass();

   210       if (m_klass_non_interface->is_interface()) {

   211         m_klass_non_interface = SystemDictionary::Object_klass();

   212 #ifdef ASSERT

   213         { ResourceMark rm;

   214           Method* m2 = m_klass_non_interface->vtable().method_at(vmindex);

   215           assert(m->name() == m2->name() && m->signature() == m2->signature(),

   216                  "at %d, %s != %s", vmindex,

   217                  m->name_and_sig_as_C_string(), m2->name_and_sig_as_C_string());

   218         }

   219 #endif //ASSERT

   220       }

   221       if (!m->is_public()) {

   222         assert(m->is_public(), "virtual call must be to public interface method");

   223         return NULL;  // elicit an error later in product build

   224       }

   225       assert(info.resolved_klass()->is_subtype_of(m_klass_non_interface), "virtual call must be type-safe");

   226       m_klass = m_klass_non_interface;

   227     }

   228     if (TraceInvokeDynamic) {

   229       ttyLocker ttyl;

   230       ResourceMark rm;

   231       tty->print_cr("memberName: invokevirtual method_holder::method: %s, receiver: %s, vtableindex: %d, access_flags:",

   232             Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),

   233             m_klass->internal_name(), vmindex);

   234        m->access_flags().print_on(tty);

   235        if (m->is_default_method()) {

   236          tty->print("default");

   237        }

   238        tty->cr();

   239     }

   240     break;

   241 

   242   case CallInfo::direct_call:

   243     vmindex = Method::nonvirtual_vtable_index;

   244     if (m->is_static()) {

   245       flags |= IS_METHOD      | (JVM_REF_invokeStatic  << REFERENCE_KIND_SHIFT);

   246     } else if (m->is_initializer()) {

   247       flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);

   248     } else {

   249       flags |= IS_METHOD      | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);

   250     }

   251     break;

   252 

   253   default:  assert(false, "bad CallInfo");  return NULL;

   254   }

   255 

   256   // @CallerSensitive annotation detected

   257   if (m->caller_sensitive()) {

   258     flags |= CALLER_SENSITIVE;

   259   }

   260 

   261   Handle resolved_method = info.resolved_method_name();

   262   assert(java_lang_invoke_ResolvedMethodName::vmtarget(resolved_method()) == m(),

   263          "Should not change after link resolultion");

   264 

   265   oop mname_oop = mname();

   266   java_lang_invoke_MemberName::set_flags  (mname_oop, flags);

   267   java_lang_invoke_MemberName::set_method (mname_oop, resolved_method());

   268   java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);   // vtable/itable index

   269   java_lang_invoke_MemberName::set_clazz  (mname_oop, m_klass->java_mirror());

   270   // Note:  name and type can be lazily computed by resolve_MemberName,

   271   // if Java code needs them as resolved String and MethodType objects.

   272   // If relevant, the vtable or itable value is stored as vmindex.

   273   // This is done eagerly, since it is readily available without

   274   // constructing any new objects.

   275   return mname();

   276 }

   277 

   278 oop MethodHandles::init_field_MemberName(Handle mname, fieldDescriptor& fd, bool is_setter) {

   279   int flags = (jushort)( fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS );

   280   flags |= IS_FIELD | ((fd.is_static() ? JVM_REF_getStatic : JVM_REF_getField) << REFERENCE_KIND_SHIFT);

   281   if (is_setter)  flags += ((JVM_REF_putField - JVM_REF_getField) << REFERENCE_KIND_SHIFT);

   282   int vmindex        = fd.offset();  // determines the field uniquely when combined with static bit

   283 

   284   oop mname_oop = mname();

   285   java_lang_invoke_MemberName::set_flags  (mname_oop, flags);

   286   java_lang_invoke_MemberName::set_method (mname_oop, NULL);

   287   java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);

   288   java_lang_invoke_MemberName::set_clazz  (mname_oop, fd.field_holder()->java_mirror());

   289 

   290   oop type = field_signature_type_or_null(fd.signature());

   291   oop name = field_name_or_null(fd.name());

   292   if (name != NULL)

   293     java_lang_invoke_MemberName::set_name(mname_oop,   name);

   294   if (type != NULL)

   295     java_lang_invoke_MemberName::set_type(mname_oop,   type);

   296   // Note:  name and type can be lazily computed by resolve_MemberName,

   297   // if Java code needs them as resolved String and Class objects.

   298   // Note that the incoming type oop might be pre-resolved (non-null).

   299   // The base clazz and field offset (vmindex) must be eagerly stored,

   300   // because they unambiguously identify the field.

   301   // Although the fieldDescriptor::_index would also identify the field,

   302   // we do not use it, because it is harder to decode.

   303   // TO DO: maybe intern mname_oop

   304   return mname();

   305 }

   306 

   307 // JVM 2.9 Special Methods:

   308 // A method is signature polymorphic if and only if all of the following conditions hold :

   309 // * It is declared in the java.lang.invoke.MethodHandle/VarHandle classes.

   310 // * It has a single formal parameter of type Object[].

   311 // * It has a return type of Object for a polymorphic return type, otherwise a fixed return type.

   312 // * It has the ACC_VARARGS and ACC_NATIVE flags set.

   313 bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {

   314   if (klass == NULL)

   315     return false;

   316   // The following test will fail spuriously during bootstrap of MethodHandle itself:

   317   //    if (klass != SystemDictionary::MethodHandle_klass())

   318   // Test the name instead:

   319   if (klass->name() != vmSymbols::java_lang_invoke_MethodHandle() &&

   320       klass->name() != vmSymbols::java_lang_invoke_VarHandle()) {

   321     return false;

   322   }

   323 

   324   // Look up signature polymorphic method with polymorphic return type

   325   Symbol* poly_sig = vmSymbols::object_array_object_signature();

   326   InstanceKlass* iklass = InstanceKlass::cast(klass);

   327   Method* m = iklass->find_method(name, poly_sig);

   328   if (m != NULL) {

   329     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;

   330     int flags = m->access_flags().as_int();

   331     if ((flags & required) == required) {

   332       return true;

   333     }

   334   }

   335 

   336   // Look up signature polymorphic method with non-polymorphic (non Object) return type

   337   int me;

   338   int ms = iklass->find_method_by_name(name, &me);

   339   if (ms == -1) return false;

   340   for (; ms < me; ms++) {

   341     Method* m = iklass->methods()->at(ms);

   342     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;

   343     int flags = m->access_flags().as_int();

   344     if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {

   345       return true;

   346     }

   347   }

   348   return false;

   349 }

   350 

   351 

   352 Symbol* MethodHandles::signature_polymorphic_intrinsic_name(vmIntrinsics::ID iid) {

   353   assert(is_signature_polymorphic_intrinsic(iid), "%d %s", iid, vmIntrinsics::name_at(iid));

   354   switch (iid) {

   355   case vmIntrinsics::_invokeBasic:      return vmSymbols::invokeBasic_name();

   356   case vmIntrinsics::_linkToVirtual:    return vmSymbols::linkToVirtual_name();

   357   case vmIntrinsics::_linkToStatic:     return vmSymbols::linkToStatic_name();

   358   case vmIntrinsics::_linkToSpecial:    return vmSymbols::linkToSpecial_name();

   359   case vmIntrinsics::_linkToInterface:  return vmSymbols::linkToInterface_name();

   360   default:

   361     fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));

   362     return 0;

   363   }

   364 }

   365 

   366 Bytecodes::Code MethodHandles::signature_polymorphic_intrinsic_bytecode(vmIntrinsics::ID id) {

   367   switch(id) {

   368     case vmIntrinsics::_linkToVirtual:   return Bytecodes::_invokevirtual;

   369     case vmIntrinsics::_linkToInterface: return Bytecodes::_invokeinterface;

   370     case vmIntrinsics::_linkToStatic:    return Bytecodes::_invokestatic;

   371     case vmIntrinsics::_linkToSpecial:   return Bytecodes::_invokespecial;

   372     case vmIntrinsics::_invokeBasic:     return Bytecodes::_invokehandle;

   373     default:

   374       fatal("unexpected id: (%d) %s", (uint)id, vmIntrinsics::name_at(id));

   375       return Bytecodes::_illegal;

   376   }

   377 }

   378 

   379 int MethodHandles::signature_polymorphic_intrinsic_ref_kind(vmIntrinsics::ID iid) {

   380   switch (iid) {

   381   case vmIntrinsics::_invokeBasic:      return 0;

   382   case vmIntrinsics::_linkToVirtual:    return JVM_REF_invokeVirtual;

   383   case vmIntrinsics::_linkToStatic:     return JVM_REF_invokeStatic;

   384   case vmIntrinsics::_linkToSpecial:    return JVM_REF_invokeSpecial;

   385   case vmIntrinsics::_linkToInterface:  return JVM_REF_invokeInterface;

   386   default:

   387     fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));

   388     return 0;

   389   }

   390 }

   391 

   392 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Symbol* name) {

   393   vmSymbols::SID name_id = vmSymbols::find_sid(name);

   394   switch (name_id) {

   395   // The ID _invokeGeneric stands for all non-static signature-polymorphic methods, except built-ins.

   396   case vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name):           return vmIntrinsics::_invokeGeneric;

   397   // The only built-in non-static signature-polymorphic method is MethodHandle.invokeBasic:

   398   case vmSymbols::VM_SYMBOL_ENUM_NAME(invokeBasic_name):      return vmIntrinsics::_invokeBasic;

   399 

   400   // There is one static signature-polymorphic method for each JVM invocation mode.

   401   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToVirtual_name):    return vmIntrinsics::_linkToVirtual;

   402   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToStatic_name):     return vmIntrinsics::_linkToStatic;

   403   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToSpecial_name):    return vmIntrinsics::_linkToSpecial;

   404   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToInterface_name):  return vmIntrinsics::_linkToInterface;

   405   default:                                                    break;

   406   }

   407 

   408   // Cover the case of invokeExact and any future variants of invokeFoo.

   409   Klass* mh_klass = SystemDictionary::well_known_klass(

   410                               SystemDictionary::WK_KLASS_ENUM_NAME(MethodHandle_klass) );

   411   if (mh_klass != NULL && is_method_handle_invoke_name(mh_klass, name)) {

   412     return vmIntrinsics::_invokeGeneric;

   413   }

   414 

   415   // Cover the case of methods on VarHandle.

   416   Klass* vh_klass = SystemDictionary::well_known_klass(

   417                               SystemDictionary::WK_KLASS_ENUM_NAME(VarHandle_klass) );

   418   if (vh_klass != NULL && is_method_handle_invoke_name(vh_klass, name)) {

   419     return vmIntrinsics::_invokeGeneric;

   420   }

   421 

   422   // Note: The pseudo-intrinsic _compiledLambdaForm is never linked against.

   423   // Instead it is used to mark lambda forms bound to invokehandle or invokedynamic.

   424   return vmIntrinsics::_none;

   425 }

   426 

   427 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Klass* klass, Symbol* name) {

   428   if (klass != NULL &&

   429       (klass->name() == vmSymbols::java_lang_invoke_MethodHandle() ||

   430        klass->name() == vmSymbols::java_lang_invoke_VarHandle())) {

   431     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);

   432     if (iid != vmIntrinsics::_none)

   433       return iid;

   434     if (is_method_handle_invoke_name(klass, name))

   435       return vmIntrinsics::_invokeGeneric;

   436   }

   437   return vmIntrinsics::_none;

   438 }

   439 

   440 

   441 // convert the external string or reflective type to an internal signature

   442 Symbol* MethodHandles::lookup_signature(oop type_str, bool intern_if_not_found, TRAPS) {

   443   if (java_lang_invoke_MethodType::is_instance(type_str)) {

   444     return java_lang_invoke_MethodType::as_signature(type_str, intern_if_not_found, THREAD);

   445   } else if (java_lang_Class::is_instance(type_str)) {

   446     return java_lang_Class::as_signature(type_str, false, THREAD);

   447   } else if (java_lang_String::is_instance_inlined(type_str)) {

   448     if (intern_if_not_found) {

   449       return java_lang_String::as_symbol(type_str, THREAD);

   450     } else {

   451       return java_lang_String::as_symbol_or_null(type_str);

   452     }

   453   } else {

   454     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);

   455   }

   456 }

   457 

   458 static const char OBJ_SIG[] = "Ljava/lang/Object;";

   459 enum { OBJ_SIG_LEN = 18 };

   460 

   461 bool MethodHandles::is_basic_type_signature(Symbol* sig) {

   462   assert(vmSymbols::object_signature()->utf8_length() == (int)OBJ_SIG_LEN, "");

   463   assert(vmSymbols::object_signature()->equals(OBJ_SIG), "");

   464   const int len = sig->utf8_length();

   465   for (int i = 0; i < len; i++) {

   466     switch (sig->byte_at(i)) {

   467     case 'L':

   468       // only java/lang/Object is valid here

   469       if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)

   470         return false;

   471       i += OBJ_SIG_LEN-1;  //-1 because of i++ in loop

   472       continue;

   473     case '(': case ')': case 'V':

   474     case 'I': case 'J': case 'F': case 'D':

   475       continue;

   476     //case '[':

   477     //case 'Z': case 'B': case 'C': case 'S':

   478     default:

   479       return false;

   480     }

   481   }

   482   return true;

   483 }

   484 

   485 Symbol* MethodHandles::lookup_basic_type_signature(Symbol* sig, bool keep_last_arg, TRAPS) {

   486   Symbol* bsig = NULL;

   487   if (sig == NULL) {

   488     return sig;

   489   } else if (is_basic_type_signature(sig)) {

   490     sig->increment_refcount();

   491     return sig;  // that was easy

   492   } else if (sig->byte_at(0) != '(') {

   493     BasicType bt = char2type(sig->byte_at(0));

   494     if (is_subword_type(bt)) {

   495       bsig = vmSymbols::int_signature();

   496     } else {

   497       assert(bt == T_OBJECT || bt == T_ARRAY, "is_basic_type_signature was false");

   498       bsig = vmSymbols::object_signature();

   499     }

   500   } else {

   501     ResourceMark rm;

   502     stringStream buffer(128);

   503     buffer.put('(');

   504     int arg_pos = 0, keep_arg_pos = -1;

   505     if (keep_last_arg)

   506       keep_arg_pos = ArgumentCount(sig).size() - 1;

   507     for (SignatureStream ss(sig); !ss.is_done(); ss.next()) {

   508       BasicType bt = ss.type();

   509       size_t this_arg_pos = buffer.size();

   510       if (ss.at_return_type()) {

   511         buffer.put(')');

   512       }

   513       if (arg_pos == keep_arg_pos) {

   514         buffer.write((char*) ss.raw_bytes(),

   515                      (int)   ss.raw_length());

   516       } else if (bt == T_OBJECT || bt == T_ARRAY) {

   517         buffer.write(OBJ_SIG, OBJ_SIG_LEN);

   518       } else {

   519         if (is_subword_type(bt))

   520           bt = T_INT;

   521         buffer.put(type2char(bt));

   522       }

   523       arg_pos++;

   524     }

   525     const char* sigstr =       buffer.base();

   526     int         siglen = (int) buffer.size();

   527     bsig = SymbolTable::new_symbol(sigstr, siglen, THREAD);

   528   }

   529   assert(is_basic_type_signature(bsig) ||

   530          // detune assert in case the injected argument is not a basic type:

   531          keep_last_arg, "");

   532   return bsig;

   533 }

   534 

   535 void MethodHandles::print_as_basic_type_signature_on(outputStream* st,

   536                                                      Symbol* sig,

   537                                                      bool keep_arrays,

   538                                                      bool keep_basic_names) {

   539   st = st ? st : tty;

   540   int len  = sig->utf8_length();

   541   int array = 0;

   542   bool prev_type = false;

   543   for (int i = 0; i < len; i++) {

   544     char ch = sig->byte_at(i);

   545     switch (ch) {

   546     case '(': case ')':

   547       prev_type = false;

   548       st->put(ch);

   549       continue;

   550     case '[':

   551       if (!keep_basic_names && keep_arrays)

   552         st->put(ch);

   553       array++;

   554       continue;

   555     case 'L':

   556       {

   557         if (prev_type)  st->put(',');

   558         int start = i+1, slash = start;

   559         while (++i < len && (ch = sig->byte_at(i)) != ';') {

   560           if (ch == '/' || ch == '.' || ch == '$')  slash = i+1;

   561         }

   562         if (slash < i)  start = slash;

   563         if (!keep_basic_names) {

   564           st->put('L');

   565         } else {

   566           for (int j = start; j < i; j++)

   567             st->put(sig->byte_at(j));

   568           prev_type = true;

   569         }

   570         break;

   571       }

   572     default:

   573       {

   574         if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {

   575           ch = '[';

   576           array = 0;

   577         }

   578         if (prev_type)  st->put(',');

   579         const char* n = NULL;

   580         if (keep_basic_names)

   581           n = type2name(char2type(ch));

   582         if (n == NULL) {

   583           // unknown letter, or we don't want to know its name

   584           st->put(ch);

   585         } else {

   586           st->print("%s", n);

   587           prev_type = true;

   588         }

   589         break;

   590       }

   591     }

   592     // Switch break goes here to take care of array suffix:

   593     if (prev_type) {

   594       while (array > 0) {

   595         st->print("[]");

   596         --array;

   597       }

   598     }

   599     array = 0;

   600   }

   601 }

   602 

   603 

   604 

   605 static oop object_java_mirror() {

   606   return SystemDictionary::Object_klass()->java_mirror();

   607 }

   608 

   609 oop MethodHandles::field_name_or_null(Symbol* s) {

   610   if (s == NULL)  return NULL;

   611   return StringTable::lookup(s);

   612 }

   613 

   614 oop MethodHandles::field_signature_type_or_null(Symbol* s) {

   615   if (s == NULL)  return NULL;

   616   BasicType bt = FieldType::basic_type(s);

   617   if (is_java_primitive(bt)) {

   618     assert(s->utf8_length() == 1, "");

   619     return java_lang_Class::primitive_mirror(bt);

   620   }

   621   // Here are some more short cuts for common types.

   622   // They are optional, since reference types can be resolved lazily.

   623   if (bt == T_OBJECT) {

   624     if (s == vmSymbols::object_signature()) {

   625       return object_java_mirror();

   626     } else if (s == vmSymbols::class_signature()) {

   627       return SystemDictionary::Class_klass()->java_mirror();

   628     } else if (s == vmSymbols::string_signature()) {

   629       return SystemDictionary::String_klass()->java_mirror();

   630     }

   631   }

   632   return NULL;

   633 }

   634 

   635 

   636 // An unresolved member name is a mere symbolic reference.

   637 // Resolving it plants a vmtarget/vmindex in it,

   638 // which refers directly to JVM internals.

   639 Handle MethodHandles::resolve_MemberName(Handle mname, Klass* caller, TRAPS) {

   640   Handle empty;

   641   assert(java_lang_invoke_MemberName::is_instance(mname()), "");

   642 

   643   if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {

   644     // Already resolved.

   645     DEBUG_ONLY(int vmindex = java_lang_invoke_MemberName::vmindex(mname()));

   646     assert(vmindex >= Method::nonvirtual_vtable_index, "");

   647     return mname;

   648   }

   649 

   650   Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));

   651   Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));

   652   Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));

   653   int    flags    =       java_lang_invoke_MemberName::flags(mname());

   654   int    ref_kind =       (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;

   655   if (!ref_kind_is_valid(ref_kind)) {

   656     THROW_MSG_(vmSymbols::java_lang_InternalError(), "obsolete MemberName format", empty);

   657   }

   658 

   659   DEBUG_ONLY(int old_vmindex);

   660   assert((old_vmindex = java_lang_invoke_MemberName::vmindex(mname())) == 0, "clean input");

   661 

   662   if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {

   663     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve", empty);

   664   }

   665 

   666   InstanceKlass* defc = NULL;

   667   {

   668     Klass* defc_klass = java_lang_Class::as_Klass(defc_oop());

   669     if (defc_klass == NULL)  return empty;  // a primitive; no resolution possible

   670     if (!defc_klass->is_instance_klass()) {

   671       if (!defc_klass->is_array_klass())  return empty;

   672       defc_klass = SystemDictionary::Object_klass();

   673     }

   674     defc = InstanceKlass::cast(defc_klass);

   675   }

   676   if (defc == NULL) {

   677     THROW_MSG_(vmSymbols::java_lang_InternalError(), "primitive class", empty);

   678   }

   679   defc->link_class(CHECK_(empty));  // possible safepoint

   680 

   681   // convert the external string name to an internal symbol

   682   TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());

   683   if (name == NULL)  return empty;  // no such name

   684   if (name == vmSymbols::class_initializer_name())

   685     return empty; // illegal name

   686 

   687   vmIntrinsics::ID mh_invoke_id = vmIntrinsics::_none;

   688   if ((flags & ALL_KINDS) == IS_METHOD &&

   689       (defc == SystemDictionary::MethodHandle_klass()) &&

   690       (ref_kind == JVM_REF_invokeVirtual ||

   691        ref_kind == JVM_REF_invokeSpecial ||

   692        // static invocation mode is required for _linkToVirtual, etc.:

   693        ref_kind == JVM_REF_invokeStatic)) {

   694     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);

   695     if (iid != vmIntrinsics::_none &&

   696         ((ref_kind == JVM_REF_invokeStatic) == is_signature_polymorphic_static(iid))) {

   697       // Virtual methods invoke and invokeExact, plus internal invokers like _invokeBasic.

   698       // For a static reference it could an internal linkage routine like _linkToVirtual, etc.

   699       mh_invoke_id = iid;

   700     }

   701   }

   702 

   703   // convert the external string or reflective type to an internal signature

   704   TempNewSymbol type = lookup_signature(type_str(), (mh_invoke_id != vmIntrinsics::_none), CHECK_(empty));

   705   if (type == NULL)  return empty;  // no such signature exists in the VM

   706 

   707   LinkInfo::AccessCheck access_check = caller != NULL ?

   708                                               LinkInfo::needs_access_check :

   709                                               LinkInfo::skip_access_check;

   710 

   711   // Time to do the lookup.

   712   switch (flags & ALL_KINDS) {

   713   case IS_METHOD:

   714     {

   715       CallInfo result;

   716       LinkInfo link_info(defc, name, type, caller, access_check);

   717       {

   718         assert(!HAS_PENDING_EXCEPTION, "");

   719         if (ref_kind == JVM_REF_invokeStatic) {

   720           LinkResolver::resolve_static_call(result,

   721                         link_info, false, THREAD);

   722         } else if (ref_kind == JVM_REF_invokeInterface) {

   723           LinkResolver::resolve_interface_call(result, Handle(), defc,

   724                         link_info, false, THREAD);

   725         } else if (mh_invoke_id != vmIntrinsics::_none) {

   726           assert(!is_signature_polymorphic_static(mh_invoke_id), "");

   727           LinkResolver::resolve_handle_call(result, link_info, THREAD);

   728         } else if (ref_kind == JVM_REF_invokeSpecial) {

   729           LinkResolver::resolve_special_call(result, Handle(),

   730                         link_info, THREAD);

   731         } else if (ref_kind == JVM_REF_invokeVirtual) {

   732           LinkResolver::resolve_virtual_call(result, Handle(), defc,

   733                         link_info, false, THREAD);

   734         } else {

   735           assert(false, "ref_kind=%d", ref_kind);

   736         }

   737         if (HAS_PENDING_EXCEPTION) {

   738           return empty;

   739         }

   740       }

   741       if (result.resolved_appendix().not_null()) {

   742         // The resolved MemberName must not be accompanied by an appendix argument,

   743         // since there is no way to bind this value into the MemberName.

   744         // Caller is responsible to prevent this from happening.

   745         THROW_MSG_(vmSymbols::java_lang_InternalError(), "appendix", empty);

   746       }

   747       result.set_resolved_method_name(CHECK_(empty));

   748       oop mname2 = init_method_MemberName(mname, result);

   749       return Handle(THREAD, mname2);

   750     }

   751   case IS_CONSTRUCTOR:

   752     {

   753       CallInfo result;

   754       LinkInfo link_info(defc, name, type, caller, access_check);

   755       {

   756         assert(!HAS_PENDING_EXCEPTION, "");

   757         if (name == vmSymbols::object_initializer_name()) {

   758           LinkResolver::resolve_special_call(result, Handle(), link_info, THREAD);

   759         } else {

   760           break;                // will throw after end of switch

   761         }

   762         if (HAS_PENDING_EXCEPTION) {

   763           return empty;

   764         }

   765       }

   766       assert(result.is_statically_bound(), "");

   767       result.set_resolved_method_name(CHECK_(empty));

   768       oop mname2 = init_method_MemberName(mname, result);

   769       return Handle(THREAD, mname2);

   770     }

   771   case IS_FIELD:

   772     {

   773       fieldDescriptor result; // find_field initializes fd if found

   774       {

   775         assert(!HAS_PENDING_EXCEPTION, "");

   776         LinkInfo link_info(defc, name, type, caller, LinkInfo::skip_access_check);

   777         LinkResolver::resolve_field(result, link_info, Bytecodes::_nop, false, THREAD);

   778         if (HAS_PENDING_EXCEPTION) {

   779           return empty;

   780         }

   781       }

   782       oop mname2 = init_field_MemberName(mname, result, ref_kind_is_setter(ref_kind));

   783       return Handle(THREAD, mname2);

   784     }

   785   default:

   786     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);

   787   }

   788 

   789   return empty;

   790 }

   791 

   792 // Conversely, a member name which is only initialized from JVM internals

   793 // may have null defc, name, and type fields.

   794 // Resolving it plants a vmtarget/vmindex in it,

   795 // which refers directly to JVM internals.

   796 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {

   797   assert(java_lang_invoke_MemberName::is_instance(mname()), "");

   798 

   799   bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);

   800   bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);

   801   bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);

   802   int flags      = java_lang_invoke_MemberName::flags(mname());

   803 

   804   if (suppress != 0) {

   805     if (suppress & _suppress_defc)  have_defc = true;

   806     if (suppress & _suppress_name)  have_name = true;

   807     if (suppress & _suppress_type)  have_type = true;

   808   }

   809 

   810   if (have_defc && have_name && have_type)  return;  // nothing needed

   811 

   812   switch (flags & ALL_KINDS) {

   813   case IS_METHOD:

   814   case IS_CONSTRUCTOR:

   815     {

   816       Method* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());

   817       if (vmtarget == NULL) {

   818         THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");

   819       }

   820       methodHandle m(THREAD, vmtarget);

   821       DEBUG_ONLY(vmtarget = NULL);  // safety

   822       if (!have_defc) {

   823         InstanceKlass* defc = m->method_holder();

   824         java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());

   825       }

   826       if (!have_name) {

   827         //not java_lang_String::create_from_symbol; let's intern member names

   828         oop name = StringTable::intern(m->name(), CHECK);

   829         java_lang_invoke_MemberName::set_name(mname(), name);

   830       }

   831       if (!have_type) {

   832         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);

   833         java_lang_invoke_MemberName::set_type(mname(), type());

   834       }

   835       return;

   836     }

   837   case IS_FIELD:

   838     {

   839       oop clazz = java_lang_invoke_MemberName::clazz(mname());

   840       if (clazz == NULL) {

   841         THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand (as field)");

   842       }

   843       InstanceKlass* defc = InstanceKlass::cast(java_lang_Class::as_Klass(clazz));

   844       DEBUG_ONLY(clazz = NULL);  // safety

   845       int vmindex  = java_lang_invoke_MemberName::vmindex(mname());

   846       bool is_static = ((flags & JVM_ACC_STATIC) != 0);

   847       fieldDescriptor fd; // find_field initializes fd if found

   848       if (!defc->find_field_from_offset(vmindex, is_static, &fd))

   849         break;                  // cannot expand

   850       if (!have_name) {

   851         //not java_lang_String::create_from_symbol; let's intern member names

   852         oop name = StringTable::intern(fd.name(), CHECK);

   853         java_lang_invoke_MemberName::set_name(mname(), name);

   854       }

   855       if (!have_type) {

   856         // If it is a primitive field type, don't mess with short strings like "I".

   857         Handle type (THREAD, field_signature_type_or_null(fd.signature()));

   858         if (type.is_null()) {

   859           type = java_lang_String::create_from_symbol(fd.signature(), CHECK);

   860         }

   861         java_lang_invoke_MemberName::set_type(mname(), type());

   862       }

   863       return;

   864     }

   865   }

   866   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");

   867 }

   868 

   869 int MethodHandles::find_MemberNames(Klass* k,

   870                                     Symbol* name, Symbol* sig,

   871                                     int mflags, Klass* caller,

   872                                     int skip, objArrayHandle results, TRAPS) {

   873   // %%% take caller into account!

   874 

   875   Thread* thread = Thread::current();

   876 

   877   if (k == NULL || !k->is_instance_klass())  return -1;

   878 

   879   int rfill = 0, rlimit = results->length(), rskip = skip;

   880   // overflow measurement:

   881   int overflow = 0, overflow_limit = MAX2(1000, rlimit);

   882 

   883   int match_flags = mflags;

   884   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);

   885   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);

   886   bool local_only = !(search_superc | search_intfc);

   887   bool classes_only = false;

   888 

   889   if (name != NULL) {

   890     if (name->utf8_length() == 0)  return 0; // a match is not possible

   891   }

   892   if (sig != NULL) {

   893     if (sig->utf8_length() == 0)  return 0; // a match is not possible

   894     if (sig->byte_at(0) == '(')

   895       match_flags &= ~(IS_FIELD | IS_TYPE);

   896     else

   897       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);

   898   }

   899 

   900   if ((match_flags & IS_TYPE) != 0) {

   901     // NYI, and Core Reflection works quite well for this query

   902   }

   903 

   904   if ((match_flags & IS_FIELD) != 0) {

   905     InstanceKlass* ik = InstanceKlass::cast(k);

   906     for (FieldStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {

   907       if (name != NULL && st.name() != name)

   908           continue;

   909       if (sig != NULL && st.signature() != sig)

   910         continue;

   911       // passed the filters

   912       if (rskip > 0) {

   913         --rskip;

   914       } else if (rfill < rlimit) {

   915         Handle result(thread, results->obj_at(rfill++));

   916         if (!java_lang_invoke_MemberName::is_instance(result()))

   917           return -99;  // caller bug!

   918         oop saved = MethodHandles::init_field_MemberName(result, st.field_descriptor());

   919         if (saved != result())

   920           results->obj_at_put(rfill-1, saved);  // show saved instance to user

   921       } else if (++overflow >= overflow_limit) {

   922         match_flags = 0; break; // got tired of looking at overflow

   923       }

   924     }

   925   }

   926 

   927   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {

   928     // watch out for these guys:

   929     Symbol* init_name   = vmSymbols::object_initializer_name();

   930     Symbol* clinit_name = vmSymbols::class_initializer_name();

   931     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>

   932     bool negate_name_test = false;

   933     // fix name so that it captures the intention of IS_CONSTRUCTOR

   934     if (!(match_flags & IS_METHOD)) {

   935       // constructors only

   936       if (name == NULL) {

   937         name = init_name;

   938       } else if (name != init_name) {

   939         return 0;               // no constructors of this method name

   940       }

   941     } else if (!(match_flags & IS_CONSTRUCTOR)) {

   942       // methods only

   943       if (name == NULL) {

   944         name = init_name;

   945         negate_name_test = true; // if we see the name, we *omit* the entry

   946       } else if (name == init_name) {

   947         return 0;               // no methods of this constructor name

   948       }

   949     } else {

   950       // caller will accept either sort; no need to adjust name

   951     }

   952     InstanceKlass* ik = InstanceKlass::cast(k);

   953     for (MethodStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {

   954       Method* m = st.method();

   955       Symbol* m_name = m->name();

   956       if (m_name == clinit_name)

   957         continue;

   958       if (name != NULL && ((m_name != name) ^ negate_name_test))

   959           continue;

   960       if (sig != NULL && m->signature() != sig)

   961         continue;

   962       // passed the filters

   963       if (rskip > 0) {

   964         --rskip;

   965       } else if (rfill < rlimit) {

   966         Handle result(thread, results->obj_at(rfill++));

   967         if (!java_lang_invoke_MemberName::is_instance(result()))

   968           return -99;  // caller bug!

   969         CallInfo info(m, NULL, CHECK_0);

   970         oop saved = MethodHandles::init_method_MemberName(result, info);

   971         if (saved != result())

   972           results->obj_at_put(rfill-1, saved);  // show saved instance to user

   973       } else if (++overflow >= overflow_limit) {

   974         match_flags = 0; break; // got tired of looking at overflow

   975       }

   976     }

   977   }

   978 

   979   // return number of elements we at leasted wanted to initialize

   980   return rfill + overflow;

   981 }

   982 

   983 // Is it safe to remove stale entries from a dependency list?

   984 static bool safe_to_expunge() {

   985   // Since parallel GC threads can concurrently iterate over a dependency

   986   // list during safepoint, it is safe to remove entries only when

   987   // CodeCache lock is held.

   988   return CodeCache_lock->owned_by_self();

   989 }

   990 

   991 void MethodHandles::add_dependent_nmethod(oop call_site, nmethod* nm) {

   992   assert_locked_or_safepoint(CodeCache_lock);

   993 

   994   oop context = java_lang_invoke_CallSite::context(call_site);

   995   DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);

   996   // Try to purge stale entries on updates.

   997   // Since GC doesn't clean dependency contexts rooted at CallSiteContext objects,

   998   // in order to avoid memory leak, stale entries are purged whenever a dependency list

   999   // is changed (both on addition and removal). Though memory reclamation is delayed,

  1000   // it avoids indefinite memory usage growth.

  1001   deps.add_dependent_nmethod(nm, /*expunge_stale_entries=*/safe_to_expunge());

  1002 }

  1003 

  1004 void MethodHandles::remove_dependent_nmethod(oop call_site, nmethod* nm) {

  1005   assert_locked_or_safepoint(CodeCache_lock);

  1006 

  1007   oop context = java_lang_invoke_CallSite::context(call_site);

  1008   DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);

  1009   deps.remove_dependent_nmethod(nm, /*expunge_stale_entries=*/safe_to_expunge());

  1010 }

  1011 

  1012 void MethodHandles::flush_dependent_nmethods(Handle call_site, Handle target) {

  1013   assert_lock_strong(Compile_lock);

  1014 

  1015   int marked = 0;

  1016   CallSiteDepChange changes(call_site, target);

  1017   {

  1018     NoSafepointVerifier nsv;

  1019     MutexLockerEx mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);

  1020 

  1021     oop context = java_lang_invoke_CallSite::context(call_site());

  1022     DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);

  1023     marked = deps.mark_dependent_nmethods(changes);

  1024   }

  1025   if (marked > 0) {

  1026     // At least one nmethod has been marked for deoptimization.

  1027     VM_Deoptimize op;

  1028     VMThread::execute(&op);

  1029   }

  1030 }

  1031 

  1032 //

  1033 // Here are the native methods in java.lang.invoke.MethodHandleNatives

  1034 // They are the private interface between this JVM and the HotSpot-specific

  1035 // Java code that implements JSR 292 method handles.

  1036 //

  1037 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way

  1038 // that intrinsic (non-JNI) native methods are defined in HotSpot.

  1039 //

  1040 

  1041 #ifndef PRODUCT

  1042 #define EACH_NAMED_CON(template, requirement) \

  1043     template(java_lang_invoke_MemberName,MN_IS_METHOD) \

  1044     template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \

  1045     template(java_lang_invoke_MemberName,MN_IS_FIELD) \

  1046     template(java_lang_invoke_MemberName,MN_IS_TYPE) \

  1047     template(java_lang_invoke_MemberName,MN_CALLER_SENSITIVE) \

  1048     template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \

  1049     template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \

  1050     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_SHIFT) \

  1051     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_MASK) \

  1052     /*end*/

  1053 

  1054 #define IGNORE_REQ(req_expr) /* req_expr */

  1055 #define ONE_PLUS(scope,value) 1+

  1056 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS, IGNORE_REQ) 0;

  1057 #define VALUE_COMMA(scope,value) scope::value,

  1058 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA, IGNORE_REQ) 0 };

  1059 #define STRING_NULL(scope,value) #value "\0"

  1060 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL, IGNORE_REQ) };

  1061 

  1062 static bool advertise_con_value(int which) {

  1063   if (which < 0)  return false;

  1064   bool ok = true;

  1065   int count = 0;

  1066 #define INC_COUNT(scope,value) \

  1067   ++count;

  1068 #define CHECK_REQ(req_expr) \

  1069   if (which < count)  return ok; \

  1070   ok = (req_expr);

  1071   EACH_NAMED_CON(INC_COUNT, CHECK_REQ);

  1072 #undef INC_COUNT

  1073 #undef CHECK_REQ

  1074   assert(count == con_value_count, "");

  1075   if (which < count)  return ok;

  1076   return false;

  1077 }

  1078 

  1079 #undef ONE_PLUS

  1080 #undef VALUE_COMMA

  1081 #undef STRING_NULL

  1082 #undef EACH_NAMED_CON

  1083 #endif // PRODUCT

  1084 

  1085 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {

  1086 #ifndef PRODUCT

  1087   if (advertise_con_value(which)) {

  1088     assert(which >= 0 && which < con_value_count, "");

  1089     int con = con_values[which];

  1090     objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));

  1091     if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {

  1092       const char* str = &con_names[0];

  1093       for (int i = 0; i < which; i++)

  1094         str += strlen(str) + 1;   // skip name and null

  1095       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);  // possible safepoint

  1096       box->obj_at_put(0, name);

  1097     }

  1098     return con;

  1099   }

  1100 #endif

  1101   return 0;

  1102 }

  1103 JVM_END

  1104 

  1105 // void init(MemberName self, AccessibleObject ref)

  1106 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {

  1107   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }

  1108   if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }

  1109   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));

  1110   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));

  1111   MethodHandles::init_MemberName(mname, target, CHECK);

  1112 }

  1113 JVM_END

  1114 

  1115 // void expand(MemberName self)

  1116 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {

  1117   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }

  1118   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));

  1119   MethodHandles::expand_MemberName(mname, 0, CHECK);

  1120 }

  1121 JVM_END

  1122 

  1123 // void resolve(MemberName self, Class<?> caller)

  1124 JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {

  1125   if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }

  1126   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));

  1127 

  1128   // The trusted Java code that calls this method should already have performed

  1129   // access checks on behalf of the given caller.  But, we can verify this.

  1130   if (VerifyMethodHandles && caller_jh != NULL &&

  1131       java_lang_invoke_MemberName::clazz(mname()) != NULL) {

  1132     Klass* reference_klass = java_lang_Class::as_Klass(java_lang_invoke_MemberName::clazz(mname()));

  1133     if (reference_klass != NULL && reference_klass->is_objArray_klass()) {

  1134       reference_klass = ObjArrayKlass::cast(reference_klass)->bottom_klass();