src/share/vm/prims/methodHandles.cpp

Sat, 01 Sep 2012 13:25:18 -0400

author
coleenp
date
Sat, 01 Sep 2012 13:25:18 -0400
changeset 4037
da91efe96a93
parent 3974
93c71eb28866
child 4041
d17383603741
permissions
-rw-r--r--

6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>

     1 /*
     2  * Copyright (c) 2008, 2012, 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/symbolTable.hpp"
    27 #include "compiler/compileBroker.hpp"
    28 #include "interpreter/interpreter.hpp"
    29 #include "interpreter/oopMapCache.hpp"
    30 #include "memory/allocation.inline.hpp"
    31 #include "memory/oopFactory.hpp"
    32 #include "prims/methodHandles.hpp"
    33 #include "runtime/compilationPolicy.hpp"
    34 #include "runtime/javaCalls.hpp"
    35 #include "runtime/reflection.hpp"
    36 #include "runtime/signature.hpp"
    37 #include "runtime/stubRoutines.hpp"
    40 /*
    41  * JSR 292 reference implementation: method handles
    42  * The JDK 7 reference implementation represented method handle
    43  * combinations as chains.  Each link in the chain had a "vmentry"
    44  * field which pointed at a bit of assembly code which performed
    45  * one transformation before dispatching to the next link in the chain.
    46  *
    47  * The current reference implementation pushes almost all code generation
    48  * responsibility to (trusted) Java code.  A method handle contains a
    49  * pointer to its "LambdaForm", which embodies all details of the method
    50  * handle's behavior.  The LambdaForm is a normal Java object, managed
    51  * by a runtime coded in Java.
    52  */
    54 bool MethodHandles::_enabled = false; // set true after successful native linkage
    55 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;
    57 //------------------------------------------------------------------------------
    58 // MethodHandles::generate_adapters
    59 //
    60 void MethodHandles::generate_adapters() {
    61   if (!EnableInvokeDynamic || SystemDictionary::MethodHandle_klass() == NULL)  return;
    63   assert(_adapter_code == NULL, "generate only once");
    65   ResourceMark rm;
    66   TraceTime timer("MethodHandles adapters generation", TraceStartupTime);
    67   _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);
    68   if (_adapter_code == NULL)
    69     vm_exit_out_of_memory(adapter_code_size, "CodeCache: no room for MethodHandles adapters");
    70   {
    71     CodeBuffer code(_adapter_code);
    72     MethodHandlesAdapterGenerator g(&code);
    73     g.generate();
    74     code.log_section_sizes("MethodHandlesAdapterBlob");
    75   }
    76 }
    78 //------------------------------------------------------------------------------
    79 // MethodHandlesAdapterGenerator::generate
    80 //
    81 void MethodHandlesAdapterGenerator::generate() {
    82   // Generate generic method handle adapters.
    83   // Generate interpreter entries
    84   for (Interpreter::MethodKind mk = Interpreter::method_handle_invoke_FIRST;
    85        mk <= Interpreter::method_handle_invoke_LAST;
    86        mk = Interpreter::MethodKind(1 + (int)mk)) {
    87     vmIntrinsics::ID iid = Interpreter::method_handle_intrinsic(mk);
    88     StubCodeMark mark(this, "MethodHandle::interpreter_entry", vmIntrinsics::name_at(iid));
    89     address entry = MethodHandles::generate_method_handle_interpreter_entry(_masm, iid);
    90     if (entry != NULL) {
    91       Interpreter::set_entry_for_kind(mk, entry);
    92     }
    93     // If the entry is not set, it will throw AbstractMethodError.
    94   }
    95 }
    97 void MethodHandles::set_enabled(bool z) {
    98   if (_enabled != z) {
    99     guarantee(z && EnableInvokeDynamic, "can only enable once, and only if -XX:+EnableInvokeDynamic");
   100     _enabled = z;
   101   }
   102 }
   104 // MemberName support
   106 // import java_lang_invoke_MemberName.*
   107 enum {
   108   IS_METHOD      = java_lang_invoke_MemberName::MN_IS_METHOD,
   109   IS_CONSTRUCTOR = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,
   110   IS_FIELD       = java_lang_invoke_MemberName::MN_IS_FIELD,
   111   IS_TYPE        = java_lang_invoke_MemberName::MN_IS_TYPE,
   112   REFERENCE_KIND_SHIFT = java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT,
   113   REFERENCE_KIND_MASK  = java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,
   114   SEARCH_SUPERCLASSES = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,
   115   SEARCH_INTERFACES   = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,
   116   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE
   117 };
   119 Handle MethodHandles::new_MemberName(TRAPS) {
   120   Handle empty;
   121   instanceKlassHandle k(THREAD, SystemDictionary::MemberName_klass());
   122   if (!k->is_initialized())  k->initialize(CHECK_(empty));
   123   return Handle(THREAD, k->allocate_instance(THREAD));
   124 }
   126 oop MethodHandles::init_MemberName(oop mname_oop, oop target_oop) {
   127   Klass* target_klass = target_oop->klass();
   128   if (target_klass == SystemDictionary::reflect_Field_klass()) {
   129     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
   130     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()
   131     int mods  = java_lang_reflect_Field::modifiers(target_oop);
   132     oop type  = java_lang_reflect_Field::type(target_oop);
   133     oop name  = java_lang_reflect_Field::name(target_oop);
   134     Klass* k = java_lang_Class::as_Klass(clazz);
   135     intptr_t offset = InstanceKlass::cast(k)->field_offset(slot);
   136     return init_field_MemberName(mname_oop, k, accessFlags_from(mods), type, name, offset);
   137   } else if (target_klass == SystemDictionary::reflect_Method_klass()) {
   138     oop clazz  = java_lang_reflect_Method::clazz(target_oop);
   139     int slot   = java_lang_reflect_Method::slot(target_oop);
   140     Klass* k = java_lang_Class::as_Klass(clazz);
   141     if (k != NULL && Klass::cast(k)->oop_is_instance()) {
   142       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
   143       return init_method_MemberName(mname_oop, m, true, k);
   144     }
   145   } else if (target_klass == SystemDictionary::reflect_Constructor_klass()) {
   146     oop clazz  = java_lang_reflect_Constructor::clazz(target_oop);
   147     int slot   = java_lang_reflect_Constructor::slot(target_oop);
   148     Klass* k = java_lang_Class::as_Klass(clazz);
   149     if (k != NULL && Klass::cast(k)->oop_is_instance()) {
   150       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
   151       return init_method_MemberName(mname_oop, m, false, k);
   152     }
   153   } else if (target_klass == SystemDictionary::MemberName_klass()) {
   154     // Note: This only works if the MemberName has already been resolved.
   155     oop clazz        = java_lang_invoke_MemberName::clazz(target_oop);
   156     int flags        = java_lang_invoke_MemberName::flags(target_oop);
   157     Metadata* vmtarget=java_lang_invoke_MemberName::vmtarget(target_oop);
   158     intptr_t vmindex = java_lang_invoke_MemberName::vmindex(target_oop);
   159     Klass* k         = java_lang_Class::as_Klass(clazz);
   160     int ref_kind     = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
   161     if (vmtarget == NULL)  return NULL;  // not resolved
   162     if ((flags & IS_FIELD) != 0) {
   163       assert(vmtarget->is_klass(), "field vmtarget is Klass*");
   164       int basic_mods = (ref_kind_is_static(ref_kind) ? JVM_ACC_STATIC : 0);
   165       // FIXME:  how does k (receiver_limit) contribute?
   166       return init_field_MemberName(mname_oop, (Klass*)vmtarget, accessFlags_from(basic_mods), NULL, NULL, vmindex);
   167     } else if ((flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
   168       assert(vmtarget->is_method(), "method or constructor vmtarget is Method*");
   169       return init_method_MemberName(mname_oop, (Method*)vmtarget, ref_kind_does_dispatch(ref_kind), k);
   170     } else {
   171       return NULL;
   172     }
   173   }
   174   return NULL;
   175 }
   177 oop MethodHandles::init_method_MemberName(oop mname_oop, Method* m, bool do_dispatch,
   178                                           Klass* receiver_limit) {
   179   AccessFlags mods = m->access_flags();
   180   int flags = (jushort)( mods.as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS );
   181   int vmindex = Method::nonvirtual_vtable_index; // implies never any dispatch
   182   Klass* mklass = m->method_holder();
   183   if (receiver_limit == NULL)
   184     receiver_limit = mklass;
   185   if (m->is_initializer()) {
   186     flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
   187   } else if (mods.is_static()) {
   188     flags |= IS_METHOD | (JVM_REF_invokeStatic << REFERENCE_KIND_SHIFT);
   189   } else if (receiver_limit != mklass &&
   190              !Klass::cast(receiver_limit)->is_subtype_of(mklass)) {
   191     return NULL;  // bad receiver limit
   192   } else if (Klass::cast(receiver_limit)->is_interface() &&
   193              Klass::cast(mklass)->is_interface()) {
   194     flags |= IS_METHOD | (JVM_REF_invokeInterface << REFERENCE_KIND_SHIFT);
   195     receiver_limit = mklass;  // ignore passed-in limit; interfaces are interconvertible
   196     vmindex = klassItable::compute_itable_index(m);
   197   } else if (mklass != receiver_limit && Klass::cast(mklass)->is_interface()) {
   198     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
   199     // it is a miranda method, so m->vtable_index is not what we want
   200     ResourceMark rm;
   201     klassVtable* vt = InstanceKlass::cast(receiver_limit)->vtable();
   202     vmindex = vt->index_of_miranda(m->name(), m->signature());
   203   } else if (!do_dispatch || m->can_be_statically_bound()) {
   204     flags |= IS_METHOD | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
   205   } else {
   206     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
   207     vmindex = m->vtable_index();
   208   }
   210   java_lang_invoke_MemberName::set_flags(mname_oop,    flags);
   211   java_lang_invoke_MemberName::set_vmtarget(mname_oop, m);
   212   java_lang_invoke_MemberName::set_vmindex(mname_oop,  vmindex);   // vtable/itable index
   213   java_lang_invoke_MemberName::set_clazz(mname_oop,    Klass::cast(receiver_limit)->java_mirror());
   214   // Note:  name and type can be lazily computed by resolve_MemberName,
   215   // if Java code needs them as resolved String and MethodType objects.
   216   // The clazz must be eagerly stored, because it provides a GC
   217   // root to help keep alive the Method*.
   218   // If relevant, the vtable or itable value is stored as vmindex.
   219   // This is done eagerly, since it is readily available without
   220   // constructing any new objects.
   221   // TO DO: maybe intern mname_oop
   222   return mname_oop;
   223 }
   225 Handle MethodHandles::init_method_MemberName(oop mname_oop, CallInfo& info, TRAPS) {
   226   Handle empty;
   227   if (info.resolved_appendix().not_null()) {
   228     // The resolved MemberName must not be accompanied by an appendix argument,
   229     // since there is no way to bind this value into the MemberName.
   230     // Caller is responsible to prevent this from happening.
   231     THROW_MSG_(vmSymbols::java_lang_InternalError(), "appendix", empty);
   232   }
   233   methodHandle m = info.resolved_method();
   234   KlassHandle defc = info.resolved_klass();
   235   int vmindex = -1;
   236   if (defc->is_interface() && Klass::cast(m->method_holder())->is_interface()) {
   237     // LinkResolver does not report itable indexes!  (fix this?)
   238     vmindex = klassItable::compute_itable_index(m());
   239   } else if (m->can_be_statically_bound()) {
   240     // LinkResolver reports vtable index even for final methods!
   241     vmindex = Method::nonvirtual_vtable_index;
   242   } else {
   243     vmindex = info.vtable_index();
   244   }
   245   oop res = init_method_MemberName(mname_oop, m(), (vmindex >= 0), defc());
   246   assert(res == NULL || (java_lang_invoke_MemberName::vmindex(res) == vmindex), "");
   247   return Handle(THREAD, res);
   248 }
   250 oop MethodHandles::init_field_MemberName(oop mname_oop, Klass* field_holder,
   251                                          AccessFlags mods, oop type, oop name,
   252                                          intptr_t offset, bool is_setter) {
   253   int flags = (jushort)( mods.as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS );
   254   flags |= IS_FIELD | ((mods.is_static() ? JVM_REF_getStatic : JVM_REF_getField) << REFERENCE_KIND_SHIFT);
   255   if (is_setter)  flags += ((JVM_REF_putField - JVM_REF_getField) << REFERENCE_KIND_SHIFT);
   256   Metadata* vmtarget = field_holder;
   257   int vmindex  = offset;  // determines the field uniquely when combined with static bit
   258   java_lang_invoke_MemberName::set_flags(mname_oop,    flags);
   259   java_lang_invoke_MemberName::set_vmtarget(mname_oop, vmtarget);
   260   java_lang_invoke_MemberName::set_vmindex(mname_oop,  vmindex);
   261   java_lang_invoke_MemberName::set_clazz(mname_oop,    Klass::cast(field_holder)->java_mirror());
   262   if (name != NULL)
   263     java_lang_invoke_MemberName::set_name(mname_oop,   name);
   264   if (type != NULL)
   265     java_lang_invoke_MemberName::set_type(mname_oop,   type);
   266   // Note:  name and type can be lazily computed by resolve_MemberName,
   267   // if Java code needs them as resolved String and Class objects.
   268   // Note that the incoming type oop might be pre-resolved (non-null).
   269   // The base clazz and field offset (vmindex) must be eagerly stored,
   270   // because they unambiguously identify the field.
   271   // Although the fieldDescriptor::_index would also identify the field,
   272   // we do not use it, because it is harder to decode.
   273   // TO DO: maybe intern mname_oop
   274   return mname_oop;
   275 }
   277 Handle MethodHandles::init_field_MemberName(oop mname_oop, FieldAccessInfo& info, TRAPS) {
   278   return Handle();
   279 #if 0 // FIXME
   280   KlassHandle field_holder = info.klass();
   281   intptr_t    field_offset = info.field_offset();
   282   return init_field_MemberName(mname_oop, field_holder(),
   283                                info.access_flags(),
   284                                type, name,
   285                                field_offset, false /*is_setter*/);
   286 #endif
   287 }
   290 // JVM 2.9 Special Methods:
   291 // A method is signature polymorphic if and only if all of the following conditions hold :
   292 // * It is declared in the java.lang.invoke.MethodHandle class.
   293 // * It has a single formal parameter of type Object[].
   294 // * It has a return type of Object.
   295 // * It has the ACC_VARARGS and ACC_NATIVE flags set.
   296 bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
   297   if (klass == NULL)
   298     return false;
   299   // The following test will fail spuriously during bootstrap of MethodHandle itself:
   300   //    if (klass != SystemDictionary::MethodHandle_klass())
   301   // Test the name instead:
   302   if (Klass::cast(klass)->name() != vmSymbols::java_lang_invoke_MethodHandle())
   303     return false;
   304   Symbol* poly_sig = vmSymbols::object_array_object_signature();
   305   Method* m = InstanceKlass::cast(klass)->find_method(name, poly_sig);
   306   if (m == NULL)  return false;
   307   int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
   308   int flags = m->access_flags().as_int();
   309   return (flags & required) == required;
   310 }
   313 Symbol* MethodHandles::signature_polymorphic_intrinsic_name(vmIntrinsics::ID iid) {
   314   assert(is_signature_polymorphic_intrinsic(iid), err_msg("iid=%d", iid));
   315   switch (iid) {
   316   case vmIntrinsics::_invokeBasic:      return vmSymbols::invokeBasic_name();
   317   case vmIntrinsics::_linkToVirtual:    return vmSymbols::linkToVirtual_name();
   318   case vmIntrinsics::_linkToStatic:     return vmSymbols::linkToStatic_name();
   319   case vmIntrinsics::_linkToSpecial:    return vmSymbols::linkToSpecial_name();
   320   case vmIntrinsics::_linkToInterface:  return vmSymbols::linkToInterface_name();
   321   }
   322   assert(false, "");
   323   return 0;
   324 }
   326 int MethodHandles::signature_polymorphic_intrinsic_ref_kind(vmIntrinsics::ID iid) {
   327   switch (iid) {
   328   case vmIntrinsics::_invokeBasic:      return 0;
   329   case vmIntrinsics::_linkToVirtual:    return JVM_REF_invokeVirtual;
   330   case vmIntrinsics::_linkToStatic:     return JVM_REF_invokeStatic;
   331   case vmIntrinsics::_linkToSpecial:    return JVM_REF_invokeSpecial;
   332   case vmIntrinsics::_linkToInterface:  return JVM_REF_invokeInterface;
   333   }
   334   assert(false, err_msg("iid=%d", iid));
   335   return 0;
   336 }
   338 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Symbol* name) {
   339   vmSymbols::SID name_id = vmSymbols::find_sid(name);
   340   switch (name_id) {
   341   // The ID _invokeGeneric stands for all non-static signature-polymorphic methods, except built-ins.
   342   case vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name):           return vmIntrinsics::_invokeGeneric;
   343   // The only built-in non-static signature-polymorphic method is MethodHandle.invokeBasic:
   344   case vmSymbols::VM_SYMBOL_ENUM_NAME(invokeBasic_name):      return vmIntrinsics::_invokeBasic;
   346   // There is one static signature-polymorphic method for each JVM invocation mode.
   347   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToVirtual_name):    return vmIntrinsics::_linkToVirtual;
   348   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToStatic_name):     return vmIntrinsics::_linkToStatic;
   349   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToSpecial_name):    return vmIntrinsics::_linkToSpecial;
   350   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToInterface_name):  return vmIntrinsics::_linkToInterface;
   351   }
   353   // Cover the case of invokeExact and any future variants of invokeFoo.
   354   Klass* mh_klass = SystemDictionary::well_known_klass(
   355                               SystemDictionary::WK_KLASS_ENUM_NAME(MethodHandle_klass) );
   356   if (mh_klass != NULL && is_method_handle_invoke_name(mh_klass, name))
   357     return vmIntrinsics::_invokeGeneric;
   359   // Note: The pseudo-intrinsic _compiledLambdaForm is never linked against.
   360   // Instead it is used to mark lambda forms bound to invokehandle or invokedynamic.
   361   return vmIntrinsics::_none;
   362 }
   364 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Klass* klass, Symbol* name) {
   365   if (klass != NULL &&
   366       Klass::cast(klass)->name() == vmSymbols::java_lang_invoke_MethodHandle()) {
   367     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
   368     if (iid != vmIntrinsics::_none)
   369       return iid;
   370     if (is_method_handle_invoke_name(klass, name))
   371       return vmIntrinsics::_invokeGeneric;
   372   }
   373   return vmIntrinsics::_none;
   374 }
   377 // convert the external string or reflective type to an internal signature
   378 Symbol* MethodHandles::lookup_signature(oop type_str, bool intern_if_not_found, TRAPS) {
   379   if (java_lang_invoke_MethodType::is_instance(type_str)) {
   380     return java_lang_invoke_MethodType::as_signature(type_str, intern_if_not_found, CHECK_NULL);
   381   } else if (java_lang_Class::is_instance(type_str)) {
   382     return java_lang_Class::as_signature(type_str, false, CHECK_NULL);
   383   } else if (java_lang_String::is_instance(type_str)) {
   384     if (intern_if_not_found) {
   385       return java_lang_String::as_symbol(type_str, CHECK_NULL);
   386     } else {
   387       return java_lang_String::as_symbol_or_null(type_str);
   388     }
   389   } else {
   390     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);
   391   }
   392 }
   394 static const char OBJ_SIG[] = "Ljava/lang/Object;";
   395 enum { OBJ_SIG_LEN = 18 };
   397 bool MethodHandles::is_basic_type_signature(Symbol* sig) {
   398   assert(vmSymbols::object_signature()->utf8_length() == (int)OBJ_SIG_LEN, "");
   399   assert(vmSymbols::object_signature()->equals(OBJ_SIG), "");
   400   const int len = sig->utf8_length();
   401   for (int i = 0; i < len; i++) {
   402     switch (sig->byte_at(i)) {
   403     case 'L':
   404       // only java/lang/Object is valid here
   405       if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)
   406         return false;
   407       i += OBJ_SIG_LEN-1;  //-1 because of i++ in loop
   408       continue;
   409     case '(': case ')': case 'V':
   410     case 'I': case 'J': case 'F': case 'D':
   411       continue;
   412     //case '[':
   413     //case 'Z': case 'B': case 'C': case 'S':
   414     default:
   415       return false;
   416     }
   417   }
   418   return true;
   419 }
   421 Symbol* MethodHandles::lookup_basic_type_signature(Symbol* sig, bool keep_last_arg, TRAPS) {
   422   Symbol* bsig = NULL;
   423   if (sig == NULL) {
   424     return sig;
   425   } else if (is_basic_type_signature(sig)) {
   426     sig->increment_refcount();
   427     return sig;  // that was easy
   428   } else if (sig->byte_at(0) != '(') {
   429     BasicType bt = char2type(sig->byte_at(0));
   430     if (is_subword_type(bt)) {
   431       bsig = vmSymbols::int_signature();
   432     } else {
   433       assert(bt == T_OBJECT || bt == T_ARRAY, "is_basic_type_signature was false");
   434       bsig = vmSymbols::object_signature();
   435     }
   436   } else {
   437     ResourceMark rm;
   438     stringStream buffer(128);
   439     buffer.put('(');
   440     int arg_pos = 0, keep_arg_pos = -1;
   441     if (keep_last_arg)
   442       keep_arg_pos = ArgumentCount(sig).size() - 1;
   443     for (SignatureStream ss(sig); !ss.is_done(); ss.next()) {
   444       BasicType bt = ss.type();
   445       size_t this_arg_pos = buffer.size();
   446       if (ss.at_return_type()) {
   447         buffer.put(')');
   448       }
   449       if (arg_pos == keep_arg_pos) {
   450         buffer.write((char*) ss.raw_bytes(),
   451                      (int)   ss.raw_length());
   452       } else if (bt == T_OBJECT || bt == T_ARRAY) {
   453         buffer.write(OBJ_SIG, OBJ_SIG_LEN);
   454       } else {
   455         if (is_subword_type(bt))
   456           bt = T_INT;
   457         buffer.put(type2char(bt));
   458       }
   459       arg_pos++;
   460     }
   461     const char* sigstr =       buffer.base();
   462     int         siglen = (int) buffer.size();
   463     bsig = SymbolTable::new_symbol(sigstr, siglen, THREAD);
   464   }
   465   assert(is_basic_type_signature(bsig) ||
   466          // detune assert in case the injected argument is not a basic type:
   467          keep_last_arg, "");
   468   return bsig;
   469 }
   471 void MethodHandles::print_as_basic_type_signature_on(outputStream* st,
   472                                                      Symbol* sig,
   473                                                      bool keep_arrays,
   474                                                      bool keep_basic_names) {
   475   st = st ? st : tty;
   476   int len  = sig->utf8_length();
   477   int array = 0;
   478   bool prev_type = false;
   479   for (int i = 0; i < len; i++) {
   480     char ch = sig->byte_at(i);
   481     switch (ch) {
   482     case '(': case ')':
   483       prev_type = false;
   484       st->put(ch);
   485       continue;
   486     case '[':
   487       if (!keep_basic_names && keep_arrays)
   488         st->put(ch);
   489       array++;
   490       continue;
   491     case 'L':
   492       {
   493         if (prev_type)  st->put(',');
   494         int start = i+1, slash = start;
   495         while (++i < len && (ch = sig->byte_at(i)) != ';') {
   496           if (ch == '/' || ch == '.' || ch == '$')  slash = i+1;
   497         }
   498         if (slash < i)  start = slash;
   499         if (!keep_basic_names) {
   500           st->put('L');
   501         } else {
   502           for (int j = start; j < i; j++)
   503             st->put(sig->byte_at(j));
   504           prev_type = true;
   505         }
   506         break;
   507       }
   508     default:
   509       {
   510         if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {
   511           ch = '[';
   512           array = 0;
   513         }
   514         if (prev_type)  st->put(',');
   515         const char* n = NULL;
   516         if (keep_basic_names)
   517           n = type2name(char2type(ch));
   518         if (n == NULL) {
   519           // unknown letter, or we don't want to know its name
   520           st->put(ch);
   521         } else {
   522           st->print(n);
   523           prev_type = true;
   524         }
   525         break;
   526       }
   527     }
   528     // Switch break goes here to take care of array suffix:
   529     if (prev_type) {
   530       while (array > 0) {
   531         st->print("[]");
   532         --array;
   533       }
   534     }
   535     array = 0;
   536   }
   537 }
   541 static oop object_java_mirror() {
   542   return Klass::cast(SystemDictionary::Object_klass())->java_mirror();
   543 }
   545 static oop field_name_or_null(Symbol* s) {
   546   if (s == NULL)  return NULL;
   547   return StringTable::lookup(s);
   548 }
   550 static oop field_signature_type_or_null(Symbol* s) {
   551   if (s == NULL)  return NULL;
   552   BasicType bt = FieldType::basic_type(s);
   553   if (is_java_primitive(bt)) {
   554     assert(s->utf8_length() == 1, "");
   555     return java_lang_Class::primitive_mirror(bt);
   556   }
   557   // Here are some more short cuts for common types.
   558   // They are optional, since reference types can be resolved lazily.
   559   if (bt == T_OBJECT) {
   560     if (s == vmSymbols::object_signature()) {
   561       return object_java_mirror();
   562     } else if (s == vmSymbols::class_signature()) {
   563       return Klass::cast(SystemDictionary::Class_klass())->java_mirror();
   564     } else if (s == vmSymbols::string_signature()) {
   565       return Klass::cast(SystemDictionary::String_klass())->java_mirror();
   566     } else {
   567       int len = s->utf8_length();
   568       if (s->byte_at(0) == 'L' && s->byte_at(len-1) == ';') {
   569         TempNewSymbol cname = SymbolTable::probe((const char*)&s->bytes()[1], len-2);
   570         if (cname == NULL)  return NULL;
   571         Klass* wkk = SystemDictionary::find_well_known_klass(cname);
   572         if (wkk == NULL)  return NULL;
   573         return Klass::cast(wkk)->java_mirror();
   574       }
   575     }
   576   }
   577   return NULL;
   578 }
   581 // An unresolved member name is a mere symbolic reference.
   582 // Resolving it plants a vmtarget/vmindex in it,
   583 // which refers directly to JVM internals.
   584 Handle MethodHandles::resolve_MemberName(Handle mname, TRAPS) {
   585   Handle empty;
   586   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
   588   if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {
   589     // Already resolved.
   590     DEBUG_ONLY(int vmindex = java_lang_invoke_MemberName::vmindex(mname()));
   591     assert(vmindex >= Method::nonvirtual_vtable_index, "");
   592     return mname;
   593   }
   595   Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));
   596   Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));
   597   Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));
   598   int    flags    =       java_lang_invoke_MemberName::flags(mname());
   599   int    ref_kind =       (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
   600   if (!ref_kind_is_valid(ref_kind)) {
   601     THROW_MSG_(vmSymbols::java_lang_InternalError(), "obsolete MemberName format", empty);
   602   }
   604   DEBUG_ONLY(int old_vmindex);
   605   assert((old_vmindex = java_lang_invoke_MemberName::vmindex(mname())) == 0, "clean input");
   607   if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {
   608     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve", empty);
   609   }
   611   instanceKlassHandle defc;
   612   {
   613     Klass* defc_klass = java_lang_Class::as_Klass(defc_oop());
   614     if (defc_klass == NULL)  return empty;  // a primitive; no resolution possible
   615     if (!Klass::cast(defc_klass)->oop_is_instance()) {
   616       if (!Klass::cast(defc_klass)->oop_is_array())  return empty;
   617       defc_klass = SystemDictionary::Object_klass();
   618     }
   619     defc = instanceKlassHandle(THREAD, defc_klass);
   620   }
   621   if (defc.is_null()) {
   622     THROW_MSG_(vmSymbols::java_lang_InternalError(), "primitive class", empty);
   623   }
   624   defc->link_class(CHECK_(empty));  // possible safepoint
   626   // convert the external string name to an internal symbol
   627   TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());
   628   if (name == NULL)  return empty;  // no such name
   629   if (name == vmSymbols::class_initializer_name())
   630     return empty; // illegal name
   632   vmIntrinsics::ID mh_invoke_id = vmIntrinsics::_none;
   633   if ((flags & ALL_KINDS) == IS_METHOD &&
   634       (defc() == SystemDictionary::MethodHandle_klass()) &&
   635       (ref_kind == JVM_REF_invokeVirtual ||
   636        ref_kind == JVM_REF_invokeSpecial ||
   637        // static invocation mode is required for _linkToVirtual, etc.:
   638        ref_kind == JVM_REF_invokeStatic)) {
   639     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
   640     if (iid != vmIntrinsics::_none &&
   641         ((ref_kind == JVM_REF_invokeStatic) == is_signature_polymorphic_static(iid))) {
   642       // Virtual methods invoke and invokeExact, plus internal invokers like _invokeBasic.
   643       // For a static reference it could an internal linkage routine like _linkToVirtual, etc.
   644       mh_invoke_id = iid;
   645     }
   646   }
   648   // convert the external string or reflective type to an internal signature
   649   TempNewSymbol type = lookup_signature(type_str(), (mh_invoke_id != vmIntrinsics::_none), CHECK_(empty));
   650   if (type == NULL)  return empty;  // no such signature exists in the VM
   652   // Time to do the lookup.
   653   switch (flags & ALL_KINDS) {
   654   case IS_METHOD:
   655     {
   656       CallInfo result;
   657       bool do_dispatch = true;  // default, neutral setting
   658       {
   659         assert(!HAS_PENDING_EXCEPTION, "");
   660         if (ref_kind == JVM_REF_invokeStatic) {
   661           //do_dispatch = false;  // no need, since statics are never dispatched
   662           LinkResolver::resolve_static_call(result,
   663                         defc, name, type, KlassHandle(), false, false, THREAD);
   664         } else if (ref_kind == JVM_REF_invokeInterface) {
   665           LinkResolver::resolve_interface_call(result, Handle(), defc,
   666                         defc, name, type, KlassHandle(), false, false, THREAD);
   667         } else if (mh_invoke_id != vmIntrinsics::_none) {
   668           assert(!is_signature_polymorphic_static(mh_invoke_id), "");
   669           LinkResolver::resolve_handle_call(result,
   670                         defc, name, type, KlassHandle(), THREAD);
   671         } else if (ref_kind == JVM_REF_invokeSpecial) {
   672           do_dispatch = false;  // force non-virtual linkage
   673           LinkResolver::resolve_special_call(result,
   674                         defc, name, type, KlassHandle(), false, THREAD);
   675         } else if (ref_kind == JVM_REF_invokeVirtual) {
   676           LinkResolver::resolve_virtual_call(result, Handle(), defc,
   677                         defc, name, type, KlassHandle(), false, false, THREAD);
   678         } else {
   679           assert(false, err_msg("ref_kind=%d", ref_kind));
   680         }
   681         if (HAS_PENDING_EXCEPTION) {
   682           return empty;
   683         }
   684       }
   685       return init_method_MemberName(mname(), result, THREAD);
   686     }
   687   case IS_CONSTRUCTOR:
   688     {
   689       CallInfo result;
   690       {
   691         assert(!HAS_PENDING_EXCEPTION, "");
   692         if (name == vmSymbols::object_initializer_name()) {
   693           LinkResolver::resolve_special_call(result,
   694                         defc, name, type, KlassHandle(), false, THREAD);
   695         } else {
   696           break;                // will throw after end of switch
   697         }
   698         if (HAS_PENDING_EXCEPTION) {
   699           return empty;
   700         }
   701       }
   702       assert(result.is_statically_bound(), "");
   703       return init_method_MemberName(mname(), result, THREAD);
   704     }
   705   case IS_FIELD:
   706     {
   707       // This is taken from LinkResolver::resolve_field, sans access checks.
   708       fieldDescriptor fd; // find_field initializes fd if found
   709       KlassHandle sel_klass(THREAD, InstanceKlass::cast(defc())->find_field(name, type, &fd));
   710       // check if field exists; i.e., if a klass containing the field def has been selected
   711       if (sel_klass.is_null())  return empty;  // should not happen
   712       oop type = field_signature_type_or_null(fd.signature());
   713       oop name = field_name_or_null(fd.name());
   714       bool is_setter = (ref_kind_is_valid(ref_kind) && ref_kind_is_setter(ref_kind));
   715       mname = Handle(THREAD,
   716                      init_field_MemberName(mname(), sel_klass(),
   717                                            fd.access_flags(), type, name, fd.offset(), is_setter));
   718       return mname;
   719     }
   720   default:
   721     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
   722   }
   724   return empty;
   725 }
   727 // Conversely, a member name which is only initialized from JVM internals
   728 // may have null defc, name, and type fields.
   729 // Resolving it plants a vmtarget/vmindex in it,
   730 // which refers directly to JVM internals.
   731 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
   732   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
   733   Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
   734   int vmindex  = java_lang_invoke_MemberName::vmindex(mname());
   735   if (vmtarget == NULL) {
   736     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
   737   }
   739   bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);
   740   bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);
   741   bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);
   742   int flags      = java_lang_invoke_MemberName::flags(mname());
   744   if (suppress != 0) {
   745     if (suppress & _suppress_defc)  have_defc = true;
   746     if (suppress & _suppress_name)  have_name = true;
   747     if (suppress & _suppress_type)  have_type = true;
   748   }
   750   if (have_defc && have_name && have_type)  return;  // nothing needed
   752   switch (flags & ALL_KINDS) {
   753   case IS_METHOD:
   754   case IS_CONSTRUCTOR:
   755     {
   756       assert(vmtarget->is_method(), "method or constructor vmtarget is Method*");
   757       methodHandle m(THREAD, (Method*)vmtarget);
   758       DEBUG_ONLY(vmtarget = NULL);  // safety
   759       if (m.is_null())  break;
   760       if (!have_defc) {
   761         Klass* defc = m->method_holder();
   762         java_lang_invoke_MemberName::set_clazz(mname(), Klass::cast(defc)->java_mirror());
   763       }
   764       if (!have_name) {
   765         //not java_lang_String::create_from_symbol; let's intern member names
   766         Handle name = StringTable::intern(m->name(), CHECK);
   767         java_lang_invoke_MemberName::set_name(mname(), name());
   768       }
   769       if (!have_type) {
   770         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
   771         java_lang_invoke_MemberName::set_type(mname(), type());
   772       }
   773       return;
   774     }
   775   case IS_FIELD:
   776     {
   777       // This is taken from LinkResolver::resolve_field, sans access checks.
   778       assert(vmtarget->is_klass(), "field vmtarget is Klass*");
   779       if (!Klass::cast((Klass*) vmtarget)->oop_is_instance())  break;
   780       instanceKlassHandle defc(THREAD, (Klass*) vmtarget);
   781       DEBUG_ONLY(vmtarget = NULL);  // safety
   782       bool is_static = ((flags & JVM_ACC_STATIC) != 0);
   783       fieldDescriptor fd; // find_field initializes fd if found
   784       if (!defc->find_field_from_offset(vmindex, is_static, &fd))
   785         break;                  // cannot expand
   786       if (!have_defc) {
   787         java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
   788       }
   789       if (!have_name) {
   790         //not java_lang_String::create_from_symbol; let's intern member names
   791         Handle name = StringTable::intern(fd.name(), CHECK);
   792         java_lang_invoke_MemberName::set_name(mname(), name());
   793       }
   794       if (!have_type) {
   795         // If it is a primitive field type, don't mess with short strings like "I".
   796         Handle type = field_signature_type_or_null(fd.signature());
   797         if (type.is_null()) {
   798           java_lang_String::create_from_symbol(fd.signature(), CHECK);
   799         }
   800         java_lang_invoke_MemberName::set_type(mname(), type());
   801       }
   802       return;
   803     }
   804   }
   805   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
   806 }
   808 int MethodHandles::find_MemberNames(Klass* k,
   809                                     Symbol* name, Symbol* sig,
   810                                     int mflags, Klass* caller,
   811                                     int skip, objArrayOop results) {
   812   DEBUG_ONLY(No_Safepoint_Verifier nsv);
   813   // this code contains no safepoints!
   815   // %%% take caller into account!
   817   if (k == NULL || !Klass::cast(k)->oop_is_instance())  return -1;
   819   int rfill = 0, rlimit = results->length(), rskip = skip;
   820   // overflow measurement:
   821   int overflow = 0, overflow_limit = MAX2(1000, rlimit);
   823   int match_flags = mflags;
   824   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
   825   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);
   826   bool local_only = !(search_superc | search_intfc);
   827   bool classes_only = false;
   829   if (name != NULL) {
   830     if (name->utf8_length() == 0)  return 0; // a match is not possible
   831   }
   832   if (sig != NULL) {
   833     if (sig->utf8_length() == 0)  return 0; // a match is not possible
   834     if (sig->byte_at(0) == '(')
   835       match_flags &= ~(IS_FIELD | IS_TYPE);
   836     else
   837       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
   838   }
   840   if ((match_flags & IS_TYPE) != 0) {
   841     // NYI, and Core Reflection works quite well for this query
   842   }
   844   if ((match_flags & IS_FIELD) != 0) {
   845     for (FieldStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
   846       if (name != NULL && st.name() != name)
   847           continue;
   848       if (sig != NULL && st.signature() != sig)
   849         continue;
   850       // passed the filters
   851       if (rskip > 0) {
   852         --rskip;
   853       } else if (rfill < rlimit) {
   854         oop result = results->obj_at(rfill++);
   855         if (!java_lang_invoke_MemberName::is_instance(result))
   856           return -99;  // caller bug!
   857         oop type = field_signature_type_or_null(st.signature());
   858         oop name = field_name_or_null(st.name());
   859         oop saved = MethodHandles::init_field_MemberName(result, st.klass()(),
   860                                                          st.access_flags(), type, name,
   861                                                          st.offset());
   862         if (saved != result)
   863           results->obj_at_put(rfill-1, saved);  // show saved instance to user
   864       } else if (++overflow >= overflow_limit) {
   865         match_flags = 0; break; // got tired of looking at overflow
   866       }
   867     }
   868   }
   870   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
   871     // watch out for these guys:
   872     Symbol* init_name   = vmSymbols::object_initializer_name();
   873     Symbol* clinit_name = vmSymbols::class_initializer_name();
   874     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>
   875     bool negate_name_test = false;
   876     // fix name so that it captures the intention of IS_CONSTRUCTOR
   877     if (!(match_flags & IS_METHOD)) {
   878       // constructors only
   879       if (name == NULL) {
   880         name = init_name;
   881       } else if (name != init_name) {
   882         return 0;               // no constructors of this method name
   883       }
   884     } else if (!(match_flags & IS_CONSTRUCTOR)) {
   885       // methods only
   886       if (name == NULL) {
   887         name = init_name;
   888         negate_name_test = true; // if we see the name, we *omit* the entry
   889       } else if (name == init_name) {
   890         return 0;               // no methods of this constructor name
   891       }
   892     } else {
   893       // caller will accept either sort; no need to adjust name
   894     }
   895     for (MethodStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
   896       Method* m = st.method();
   897       Symbol* m_name = m->name();
   898       if (m_name == clinit_name)
   899         continue;
   900       if (name != NULL && ((m_name != name) ^ negate_name_test))
   901           continue;
   902       if (sig != NULL && m->signature() != sig)
   903         continue;
   904       // passed the filters
   905       if (rskip > 0) {
   906         --rskip;
   907       } else if (rfill < rlimit) {
   908         oop result = results->obj_at(rfill++);
   909         if (!java_lang_invoke_MemberName::is_instance(result))
   910           return -99;  // caller bug!
   911         oop saved = MethodHandles::init_method_MemberName(result, m, true, NULL);
   912         if (saved != result)
   913           results->obj_at_put(rfill-1, saved);  // show saved instance to user
   914       } else if (++overflow >= overflow_limit) {
   915         match_flags = 0; break; // got tired of looking at overflow
   916       }
   917     }
   918   }
   920   // return number of elements we at leasted wanted to initialize
   921   return rfill + overflow;
   922 }
   923 //
   924 // Here are the native methods in java.lang.invoke.MethodHandleNatives
   925 // They are the private interface between this JVM and the HotSpot-specific
   926 // Java code that implements JSR 292 method handles.
   927 //
   928 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way
   929 // that intrinsic (non-JNI) native methods are defined in HotSpot.
   930 //
   932 JVM_ENTRY(jint, MHN_getConstant(JNIEnv *env, jobject igcls, jint which)) {
   933   switch (which) {
   934   case MethodHandles::GC_COUNT_GWT:
   935 #ifdef COMPILER2
   936     return true;
   937 #else
   938     return false;
   939 #endif
   940   }
   941   return 0;
   942 }
   943 JVM_END
   945 #ifndef PRODUCT
   946 #define EACH_NAMED_CON(template, requirement) \
   947     template(MethodHandles,GC_COUNT_GWT) \
   948     template(java_lang_invoke_MemberName,MN_IS_METHOD) \
   949     template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \
   950     template(java_lang_invoke_MemberName,MN_IS_FIELD) \
   951     template(java_lang_invoke_MemberName,MN_IS_TYPE) \
   952     template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \
   953     template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \
   954     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_SHIFT) \
   955     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_MASK) \
   956     template(MethodHandles,GC_LAMBDA_SUPPORT) \
   957     /*end*/
   959 #define IGNORE_REQ(req_expr) /* req_expr */
   960 #define ONE_PLUS(scope,value) 1+
   961 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS, IGNORE_REQ) 0;
   962 #define VALUE_COMMA(scope,value) scope::value,
   963 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA, IGNORE_REQ) 0 };
   964 #define STRING_NULL(scope,value) #value "\0"
   965 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL, IGNORE_REQ) };
   967 static bool advertise_con_value(int which) {
   968   if (which < 0)  return false;
   969   bool ok = true;
   970   int count = 0;
   971 #define INC_COUNT(scope,value) \
   972   ++count;
   973 #define CHECK_REQ(req_expr) \
   974   if (which < count)  return ok; \
   975   ok = (req_expr);
   976   EACH_NAMED_CON(INC_COUNT, CHECK_REQ);
   977 #undef INC_COUNT
   978 #undef CHECK_REQ
   979   assert(count == con_value_count, "");
   980   if (which < count)  return ok;
   981   return false;
   982 }
   984 #undef ONE_PLUS
   985 #undef VALUE_COMMA
   986 #undef STRING_NULL
   987 #undef EACH_NAMED_CON
   988 #endif // PRODUCT
   990 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
   991 #ifndef PRODUCT
   992   if (advertise_con_value(which)) {
   993     assert(which >= 0 && which < con_value_count, "");
   994     int con = con_values[which];
   995     objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));
   996     if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
   997       const char* str = &con_names[0];
   998       for (int i = 0; i < which; i++)
   999         str += strlen(str) + 1;   // skip name and null
  1000       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);  // possible safepoint
  1001       box->obj_at_put(0, name);
  1003     return con;
  1005 #endif
  1006   return 0;
  1008 JVM_END
  1010 // void init(MemberName self, AccessibleObject ref)
  1011 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
  1012   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
  1013   if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
  1014   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
  1015   oop target_oop = JNIHandles::resolve_non_null(target_jh);
  1016   MethodHandles::init_MemberName(mname(), target_oop);
  1018 JVM_END
  1020 // void expand(MemberName self)
  1021 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
  1022   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
  1023   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
  1024   MethodHandles::expand_MemberName(mname, 0, CHECK);
  1026 JVM_END
  1028 // void resolve(MemberName self, Class<?> caller)
  1029 JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
  1030   if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }
  1031   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
  1033   // The trusted Java code that calls this method should already have performed
  1034   // access checks on behalf of the given caller.  But, we can verify this.
  1035   if (VerifyMethodHandles && caller_jh != NULL &&
  1036       java_lang_invoke_MemberName::clazz(mname()) != NULL) {
  1037     Klass* reference_klass = java_lang_Class::as_Klass(java_lang_invoke_MemberName::clazz(mname()));
  1038     if (reference_klass != NULL) {
  1039       // Emulate LinkResolver::check_klass_accessability.
  1040       Klass* caller = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
  1041       if (!Reflection::verify_class_access(caller,
  1042                                            reference_klass,
  1043                                            true)) {
  1044         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), Klass::cast(reference_klass)->external_name());
  1049   Handle resolved = MethodHandles::resolve_MemberName(mname, CHECK_NULL);
  1050   if (resolved.is_null()) {
  1051     int flags = java_lang_invoke_MemberName::flags(mname());
  1052     int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
  1053     if (!MethodHandles::ref_kind_is_valid(ref_kind)) {
  1054       THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "obsolete MemberName format");
  1056     if ((flags & ALL_KINDS) == IS_FIELD) {
  1057       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), "field resolution failed");
  1058     } else if ((flags & ALL_KINDS) == IS_METHOD ||
  1059                (flags & ALL_KINDS) == IS_CONSTRUCTOR) {
  1060       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchFieldError(), "method resolution failed");
  1061     } else {
  1062       THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "resolution failed");
  1066   return JNIHandles::make_local(THREAD, resolved());
  1068 JVM_END
  1070 static jlong find_member_field_offset(oop mname, bool must_be_static, TRAPS) {
  1071   if (mname == NULL ||
  1072       java_lang_invoke_MemberName::vmtarget(mname) == NULL) {
  1073     THROW_MSG_0(vmSymbols::java_lang_InternalError(), "mname not resolved");
  1074   } else {
  1075     int flags = java_lang_invoke_MemberName::flags(mname);
  1076     if ((flags & IS_FIELD) != 0 &&
  1077         (must_be_static
  1078          ? (flags & JVM_ACC_STATIC) != 0
  1079          : (flags & JVM_ACC_STATIC) == 0)) {
  1080       int vmindex = java_lang_invoke_MemberName::vmindex(mname);
  1081       return (jlong) vmindex;
  1084   const char* msg = (must_be_static ? "static field required" : "non-static field required");
  1085   THROW_MSG_0(vmSymbols::java_lang_InternalError(), msg);
  1086   return 0;
  1089 JVM_ENTRY(jlong, MHN_objectFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
  1090   return find_member_field_offset(JNIHandles::resolve(mname_jh), false, THREAD);
  1092 JVM_END
  1094 JVM_ENTRY(jlong, MHN_staticFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
  1095   return find_member_field_offset(JNIHandles::resolve(mname_jh), true, THREAD);
  1097 JVM_END
  1099 JVM_ENTRY(jobject, MHN_staticFieldBase(JNIEnv *env, jobject igcls, jobject mname_jh)) {
  1100   // use the other function to perform sanity checks:
  1101   jlong ignore = find_member_field_offset(JNIHandles::resolve(mname_jh), true, CHECK_NULL);
  1102   oop clazz = java_lang_invoke_MemberName::clazz(JNIHandles::resolve_non_null(mname_jh));
  1103   return JNIHandles::make_local(THREAD, clazz);
  1105 JVM_END
  1107 JVM_ENTRY(jobject, MHN_getMemberVMInfo(JNIEnv *env, jobject igcls, jobject mname_jh)) {
  1108   if (mname_jh == NULL)  return NULL;
  1109   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
  1110   intptr_t vmindex  = java_lang_invoke_MemberName::vmindex(mname());
  1111   Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
  1112   objArrayHandle result = oopFactory::new_objArray(SystemDictionary::Object_klass(), 2, CHECK_NULL);
  1113   jvalue vmindex_value; vmindex_value.j = (long)vmindex;
  1114   oop x = java_lang_boxing_object::create(T_LONG, &vmindex_value, CHECK_NULL);
  1115   result->obj_at_put(0, x);
  1116   x = NULL;
  1117   if (vmtarget == NULL) {
  1118     x = NULL;
  1119   } else if (vmtarget->is_klass()) {
  1120     x = Klass::cast((Klass*) vmtarget)->java_mirror();
  1121   } else if (vmtarget->is_method()) {
  1122     Handle mname2 = MethodHandles::new_MemberName(CHECK_NULL);
  1123     x = MethodHandles::init_method_MemberName(mname2(), (Method*)vmtarget, false, NULL);
  1125   result->obj_at_put(1, x);
  1126   return JNIHandles::make_local(env, result());
  1128 JVM_END
  1132 //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
  1133 //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
  1134 JVM_ENTRY(jint, MHN_getMembers(JNIEnv *env, jobject igcls,
  1135                                jclass clazz_jh, jstring name_jh, jstring sig_jh,
  1136                                int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
  1137   if (clazz_jh == NULL || results_jh == NULL)  return -1;
  1138   KlassHandle k(THREAD, java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz_jh)));
  1140   objArrayHandle results(THREAD, (objArrayOop) JNIHandles::resolve(results_jh));
  1141   if (results.is_null() || !results->is_objArray())  return -1;
  1143   TempNewSymbol name = NULL;
  1144   TempNewSymbol sig = NULL;
  1145   if (name_jh != NULL) {
  1146     name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
  1147     if (name == NULL)  return 0; // a match is not possible
  1149   if (sig_jh != NULL) {
  1150     sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
  1151     if (sig == NULL)  return 0; // a match is not possible
  1154   KlassHandle caller;
  1155   if (caller_jh != NULL) {
  1156     oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
  1157     if (!java_lang_Class::is_instance(caller_oop))  return -1;
  1158     caller = KlassHandle(THREAD, java_lang_Class::as_Klass(caller_oop));
  1161   if (name != NULL && sig != NULL && results.not_null()) {
  1162     // try a direct resolve
  1163     // %%% TO DO
  1166   int res = MethodHandles::find_MemberNames(k(), name, sig, mflags,
  1167                                             caller(), skip, results());
  1168   // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
  1169   return res;
  1171 JVM_END
  1173 JVM_ENTRY(void, MHN_setCallSiteTargetNormal(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
  1174   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
  1175   Handle target   (THREAD, JNIHandles::resolve(target_jh));
  1177     // Walk all nmethods depending on this call site.
  1178     MutexLocker mu(Compile_lock, thread);
  1179     Universe::flush_dependents_on(call_site, target);
  1181   java_lang_invoke_CallSite::set_target(call_site(), target());
  1183 JVM_END
  1185 JVM_ENTRY(void, MHN_setCallSiteTargetVolatile(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
  1186   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
  1187   Handle target   (THREAD, JNIHandles::resolve(target_jh));
  1189     // Walk all nmethods depending on this call site.
  1190     MutexLocker mu(Compile_lock, thread);
  1191     Universe::flush_dependents_on(call_site, target);
  1193   java_lang_invoke_CallSite::set_target_volatile(call_site(), target());
  1195 JVM_END
  1197 JVM_ENTRY(jobject, MH_invoke_UOE(JNIEnv *env, jobject igmh, jobjectArray igargs)) {
  1198     TempNewSymbol UOE_name = SymbolTable::new_symbol("java/lang/UnsupportedOperationException", CHECK_NULL);
  1199     THROW_MSG_NULL(UOE_name, "MethodHandle.invoke cannot be invoked reflectively");
  1200     return NULL;
  1202 JVM_END
  1204 JVM_ENTRY(jobject, MH_invokeExact_UOE(JNIEnv *env, jobject igmh, jobjectArray igargs)) {
  1205     TempNewSymbol UOE_name = SymbolTable::new_symbol("java/lang/UnsupportedOperationException", CHECK_NULL);
  1206     THROW_MSG_NULL(UOE_name, "MethodHandle.invokeExact cannot be invoked reflectively");
  1207     return NULL;
  1209 JVM_END
  1211 /// JVM_RegisterMethodHandleMethods
  1213 #undef CS  // Solaris builds complain
  1215 #define LANG "Ljava/lang/"
  1216 #define JLINV "Ljava/lang/invoke/"
  1218 #define OBJ   LANG"Object;"
  1219 #define CLS   LANG"Class;"
  1220 #define STRG  LANG"String;"
  1221 #define CS    JLINV"CallSite;"
  1222 #define MT    JLINV"MethodType;"
  1223 #define MH    JLINV"MethodHandle;"
  1224 #define MEM   JLINV"MemberName;"
  1226 #define CC (char*)  /*cast a literal from (const char*)*/
  1227 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
  1229 // These are the native methods on java.lang.invoke.MethodHandleNatives.
  1230 static JNINativeMethod required_methods_JDK8[] = {
  1231   {CC"init",                      CC"("MEM""OBJ")V",                     FN_PTR(MHN_init_Mem)},
  1232   {CC"expand",                    CC"("MEM")V",                          FN_PTR(MHN_expand_Mem)},
  1233   {CC"resolve",                   CC"("MEM""CLS")"MEM,                   FN_PTR(MHN_resolve_Mem)},
  1234   {CC"getConstant",               CC"(I)I",                              FN_PTR(MHN_getConstant)},
  1235   //  static native int getNamedCon(int which, Object[] name)
  1236   {CC"getNamedCon",               CC"(I["OBJ")I",                        FN_PTR(MHN_getNamedCon)},
  1237   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
  1238   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
  1239   {CC"getMembers",                CC"("CLS""STRG""STRG"I"CLS"I["MEM")I", FN_PTR(MHN_getMembers)},
  1240   {CC"objectFieldOffset",         CC"("MEM")J",                          FN_PTR(MHN_objectFieldOffset)},
  1241   {CC"setCallSiteTargetNormal",   CC"("CS""MH")V",                       FN_PTR(MHN_setCallSiteTargetNormal)},
  1242   {CC"setCallSiteTargetVolatile", CC"("CS""MH")V",                       FN_PTR(MHN_setCallSiteTargetVolatile)},
  1243   {CC"staticFieldOffset",         CC"("MEM")J",                          FN_PTR(MHN_staticFieldOffset)},
  1244   {CC"staticFieldBase",           CC"("MEM")"OBJ,                        FN_PTR(MHN_staticFieldBase)},
  1245   {CC"getMemberVMInfo",           CC"("MEM")"OBJ,                        FN_PTR(MHN_getMemberVMInfo)}
  1246 };
  1248 static JNINativeMethod invoke_methods[] = {
  1249   {CC"invoke",                    CC"(["OBJ")"OBJ,                       FN_PTR(MH_invoke_UOE)},
  1250   {CC"invokeExact",               CC"(["OBJ")"OBJ,                       FN_PTR(MH_invokeExact_UOE)}
  1251 };
  1253 // This one function is exported, used by NativeLookup.
  1255 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
  1256   if (!EnableInvokeDynamic) {
  1257     warning("JSR 292 is disabled in this JVM.  Use -XX:+UnlockDiagnosticVMOptions -XX:+EnableInvokeDynamic to enable.");
  1258     return;  // bind nothing
  1261   assert(!MethodHandles::enabled(), "must not be enabled");
  1262   bool enable_MH = true;
  1264   jclass MH_class = NULL;
  1265   if (SystemDictionary::MethodHandle_klass() == NULL) {
  1266     enable_MH = false;
  1267   } else {
  1268     oop mirror = Klass::cast(SystemDictionary::MethodHandle_klass())->java_mirror();
  1269     MH_class = (jclass) JNIHandles::make_local(env, mirror);
  1272   int status;
  1274   if (enable_MH) {
  1275     ThreadToNativeFromVM ttnfv(thread);
  1277     status = env->RegisterNatives(MHN_class, required_methods_JDK8, sizeof(required_methods_JDK8)/sizeof(JNINativeMethod));
  1278     if (status == JNI_OK && !env->ExceptionOccurred()) {
  1279       status = env->RegisterNatives(MH_class, invoke_methods, sizeof(invoke_methods)/sizeof(JNINativeMethod));
  1281     if (status != JNI_OK || env->ExceptionOccurred()) {
  1282       warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
  1283       enable_MH = false;
  1284       env->ExceptionClear();
  1288   if (TraceInvokeDynamic) {
  1289     tty->print_cr("MethodHandle support loaded (using LambdaForms)");
  1292   if (enable_MH) {
  1293     MethodHandles::generate_adapters();
  1294     MethodHandles::set_enabled(true);
  1297 JVM_END

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