jdk8-mips64-public/hotspot: src/share/vm/prims/methodHandles.cpp@987e948ebbc8 (annotated)

src/share/vm/prims/methodHandles.cpp@987e948ebbc8 (annotated)

src/share/vm/prims/methodHandles.cpp

Sat, 17 Oct 2009 19:51:05 -0700

author: jrose
date: Sat, 17 Oct 2009 19:51:05 -0700
changeset 1474: 987e948ebbc8
parent 1161: be93aad57795
child 1494: 389049f3f393
permissions: -rw-r--r--

6815692: method handle code needs some cleanup (post-6655638)
Summary: correctly raise exceptions, support safe bitwise "raw" conversions, fix bugs revealed by VerifyMethodHandles, remove dead code, improve debugging support
Reviewed-by: never, twisti

 /*
  * Copyright 2008-2009 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 /*
  * JSR 292 reference implementation: method handles
  */
 #include "incls/_precompiled.incl"
 #include "incls/_methodHandles.cpp.incl"
 bool MethodHandles::_enabled = false; // set true after successful native linkage
 MethodHandleEntry* MethodHandles::_entries[MethodHandles::_EK_LIMIT] = {NULL};
 const char*        MethodHandles::_entry_names[_EK_LIMIT+1] = {
   "raise_exception",
   "invokestatic",               // how a MH emulates invokestatic
   "invokespecial",              // ditto for the other invokes...
   "invokevirtual",
   "invokeinterface",
   "bound_ref",                  // these are for BMH...
   "bound_int",
   "bound_long",
   "bound_ref_direct",           // (direct versions have a direct methodOop)
   "bound_int_direct",
   "bound_long_direct",
   // starting at _adapter_mh_first:
   "adapter_retype_only",       // these are for AMH...
   "adapter_retype_raw",
   "adapter_check_cast",
   "adapter_prim_to_prim",
   "adapter_ref_to_prim",
   "adapter_prim_to_ref",
   "adapter_swap_args",
   "adapter_rot_args",
   "adapter_dup_args",
   "adapter_drop_args",
   "adapter_collect_args",
   "adapter_spread_args",
   "adapter_flyby",
   "adapter_ricochet",
   // optimized adapter types:
   "adapter_swap_args/1",
   "adapter_swap_args/2",
   "adapter_rot_args/1,up",
   "adapter_rot_args/1,down",
   "adapter_rot_args/2,up",
   "adapter_rot_args/2,down",
   "adapter_prim_to_prim/i2i",
   "adapter_prim_to_prim/l2i",
   "adapter_prim_to_prim/d2f",
   "adapter_prim_to_prim/i2l",
   "adapter_prim_to_prim/f2d",
   "adapter_ref_to_prim/unboxi",
   "adapter_ref_to_prim/unboxl",
   "adapter_spread_args/0",
   "adapter_spread_args/1",
   "adapter_spread_args/more",
   NULL
 };
 jobject MethodHandles::_raise_exception_method;
 #ifdef ASSERT
 bool MethodHandles::spot_check_entry_names() {
   assert(!strcmp(entry_name(_invokestatic_mh), "invokestatic"), "");
   assert(!strcmp(entry_name(_bound_ref_mh), "bound_ref"), "");
   assert(!strcmp(entry_name(_adapter_retype_only), "adapter_retype_only"), "");
   assert(!strcmp(entry_name(_adapter_ricochet), "adapter_ricochet"), "");
   assert(!strcmp(entry_name(_adapter_opt_unboxi), "adapter_ref_to_prim/unboxi"), "");
   return true;
 }
 #endif
 void MethodHandles::set_enabled(bool z) {
   if (_enabled != z) {
     guarantee(z && EnableMethodHandles, "can only enable once, and only if -XX:+EnableMethodHandles");
     _enabled = z;
   }
 }
 // Note: A method which does not have a TRAPS argument cannot block in the GC
 // or throw exceptions.  Such methods are used in this file to do something quick
 // and local, like parse a data structure.  For speed, such methods work on plain
 // oops, not handles.  Trapping methods uniformly operate on handles.
 methodOop MethodHandles::decode_vmtarget(oop vmtarget, int vmindex, oop mtype,
                                          klassOop& receiver_limit_result, int& decode_flags_result) {
   if (vmtarget == NULL)  return NULL;
   assert(methodOopDesc::nonvirtual_vtable_index < 0, "encoding");
   if (vmindex < 0) {
     // this DMH performs no dispatch; it is directly bound to a methodOop
     // A MemberName may either be directly bound to a methodOop,
     // or it may use the klass/index form; both forms mean the same thing.
     methodOop m = decode_methodOop(methodOop(vmtarget), decode_flags_result);
     if ((decode_flags_result & _dmf_has_receiver) != 0
         && java_dyn_MethodType::is_instance(mtype)) {
       // Extract receiver type restriction from mtype.ptypes[0].
       objArrayOop ptypes = java_dyn_MethodType::ptypes(mtype);
       oop ptype0 = (ptypes == NULL || ptypes->length() < 1) ? oop(NULL) : ptypes->obj_at(0);
       if (java_lang_Class::is_instance(ptype0))
         receiver_limit_result = java_lang_Class::as_klassOop(ptype0);
     }
     if (vmindex == methodOopDesc::nonvirtual_vtable_index) {
       // this DMH can be an "invokespecial" version
       decode_flags_result &= ~_dmf_does_dispatch;
     } else {
       assert(vmindex == methodOopDesc::invalid_vtable_index, "random vmindex?");
     }
     return m;
   } else {
     decode_flags_result |= MethodHandles::_dmf_does_dispatch;
     assert(vmtarget->is_klass(), "must be class or interface");
     receiver_limit_result = (klassOop)vmtarget;
     Klass* tk = Klass::cast((klassOop)vmtarget);
     if (tk->is_interface()) {
       // an itable linkage is <interface, itable index>
       decode_flags_result |= MethodHandles::_dmf_from_interface;
       return klassItable::method_for_itable_index((klassOop)vmtarget, vmindex);
     } else {
       if (!tk->oop_is_instance())
         tk = instanceKlass::cast(SystemDictionary::object_klass());
       return ((instanceKlass*)tk)->method_at_vtable(vmindex);
     }
   }
 }
 // MemberName and DirectMethodHandle have the same linkage to the JVM internals.
 // (MemberName is the non-operational name used for queries and setup.)
 methodOop MethodHandles::decode_DirectMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
   oop vmtarget = sun_dyn_DirectMethodHandle::vmtarget(mh);
   int vmindex  = sun_dyn_DirectMethodHandle::vmindex(mh);
   oop mtype    = sun_dyn_DirectMethodHandle::type(mh);
   return decode_vmtarget(vmtarget, vmindex, mtype, receiver_limit_result, decode_flags_result);
 }
 methodOop MethodHandles::decode_BoundMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
   assert(sun_dyn_BoundMethodHandle::is_instance(mh), "");
   assert(mh->klass() != SystemDictionary::AdapterMethodHandle_klass(), "");
   for (oop bmh = mh;;) {
     // Bound MHs can be stacked to bind several arguments.
     oop target = java_dyn_MethodHandle::vmtarget(bmh);
     if (target == NULL)  return NULL;
     decode_flags_result |= MethodHandles::_dmf_binds_argument;
     klassOop tk = target->klass();
     if (tk == SystemDictionary::BoundMethodHandle_klass()) {
       bmh = target;
       continue;
     } else {
       if (java_dyn_MethodHandle::is_subclass(tk)) {
         //assert(tk == SystemDictionary::DirectMethodHandle_klass(), "end of BMH chain must be DMH");
         return decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
       } else {
         // Optimized case:  binding a receiver to a non-dispatched DMH
         // short-circuits directly to the methodOop.
         // (It might be another argument besides a receiver also.)
         assert(target->is_method(), "must be a simple method");
         methodOop m = (methodOop) target;
         decode_flags_result |= MethodHandles::_dmf_binds_method;
         return m;
       }
     }
   }
 }
 methodOop MethodHandles::decode_AdapterMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
   assert(mh->klass() == SystemDictionary::AdapterMethodHandle_klass(), "");
   for (oop amh = mh;;) {
     // Adapter MHs can be stacked to convert several arguments.
     int conv_op = adapter_conversion_op(sun_dyn_AdapterMethodHandle::conversion(amh));
     decode_flags_result |= (_dmf_adapter_lsb << conv_op) & _DMF_ADAPTER_MASK;
     oop target = java_dyn_MethodHandle::vmtarget(amh);
     if (target == NULL)  return NULL;
     klassOop tk = target->klass();
     if (tk == SystemDictionary::AdapterMethodHandle_klass()) {
       amh = target;
       continue;
     } else {
       // must be a BMH (which will bind some more arguments) or a DMH (for the final call)
       return MethodHandles::decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
     }
   }
 }
 methodOop MethodHandles::decode_MethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
   if (mh == NULL)  return NULL;
   klassOop mhk = mh->klass();
   assert(java_dyn_MethodHandle::is_subclass(mhk), "must be a MethodHandle");
   if (mhk == SystemDictionary::DirectMethodHandle_klass()) {
     return decode_DirectMethodHandle(mh, receiver_limit_result, decode_flags_result);
   } else if (mhk == SystemDictionary::BoundMethodHandle_klass()) {
     return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
   } else if (mhk == SystemDictionary::AdapterMethodHandle_klass()) {
     return decode_AdapterMethodHandle(mh, receiver_limit_result, decode_flags_result);
   } else if (sun_dyn_BoundMethodHandle::is_subclass(mhk)) {
     // could be a JavaMethodHandle (but not an adapter MH)
     return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
   } else {
     assert(false, "cannot parse this MH");
     return NULL;              // random MH?
   }
 }
 methodOop MethodHandles::decode_methodOop(methodOop m, int& decode_flags_result) {
   assert(m->is_method(), "");
   if (m->is_static()) {
     // check that signature begins '(L' or '([' (not '(I', '()', etc.)
     symbolOop sig = m->signature();
     BasicType recv_bt = char2type(sig->byte_at(1));
     // Note: recv_bt might be T_ILLEGAL if byte_at(2) is ')'
     assert(sig->byte_at(0) == '(', "must be method sig");
     if (recv_bt == T_OBJECT || recv_bt == T_ARRAY)
       decode_flags_result |= _dmf_has_receiver;
   } else {
     // non-static method
     decode_flags_result |= _dmf_has_receiver;
     if (!m->can_be_statically_bound() && !m->is_initializer()) {
       decode_flags_result |= _dmf_does_dispatch;
       if (Klass::cast(m->method_holder())->is_interface())
         decode_flags_result |= _dmf_from_interface;
     }
   }
   return m;
 }
 // A trusted party is handing us a cookie to determine a method.
 // Let's boil it down to the method oop they really want.
 methodOop MethodHandles::decode_method(oop x, klassOop& receiver_limit_result, int& decode_flags_result) {
   decode_flags_result = 0;
   receiver_limit_result = NULL;
   klassOop xk = x->klass();
   if (xk == Universe::methodKlassObj()) {
     return decode_methodOop((methodOop) x, decode_flags_result);
   } else if (xk == SystemDictionary::MemberName_klass()) {
     // Note: This only works if the MemberName has already been resolved.
     return decode_MemberName(x, receiver_limit_result, decode_flags_result);
   } else if (java_dyn_MethodHandle::is_subclass(xk)) {
     return decode_MethodHandle(x, receiver_limit_result, decode_flags_result);
   } else if (xk == SystemDictionary::reflect_method_klass()) {
     oop clazz  = java_lang_reflect_Method::clazz(x);
     int slot   = java_lang_reflect_Method::slot(x);
     klassOop k = java_lang_Class::as_klassOop(clazz);
     if (k != NULL && Klass::cast(k)->oop_is_instance())
       return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
                               decode_flags_result);
   } else if (xk == SystemDictionary::reflect_constructor_klass()) {
     oop clazz  = java_lang_reflect_Constructor::clazz(x);
     int slot   = java_lang_reflect_Constructor::slot(x);
     klassOop k = java_lang_Class::as_klassOop(clazz);
     if (k != NULL && Klass::cast(k)->oop_is_instance())
       return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
                               decode_flags_result);
   } else {
     // unrecognized object
     assert(!x->is_method(), "already checked");
     assert(!sun_dyn_MemberName::is_instance(x), "already checked");
   }
   return NULL;
 }
 int MethodHandles::decode_MethodHandle_stack_pushes(oop mh) {
   if (mh->klass() == SystemDictionary::DirectMethodHandle_klass())
     return 0;                   // no push/pop
   int this_vmslots = java_dyn_MethodHandle::vmslots(mh);
   int last_vmslots = 0;
   oop last_mh = mh;
   for (;;) {
     oop target = java_dyn_MethodHandle::vmtarget(last_mh);
     if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
       last_vmslots = java_dyn_MethodHandle::vmslots(target);
       break;
     } else if (!java_dyn_MethodHandle::is_instance(target)) {
       // might be klass or method
       assert(target->is_method(), "must get here with a direct ref to method");
       last_vmslots = methodOop(target)->size_of_parameters();
       break;
     }
     last_mh = target;
   }
   // If I am called with fewer VM slots than my ultimate callee,
   // it must be that I push the additionally needed slots.
   // Likewise if am called with more VM slots, I will pop them.
   return (last_vmslots - this_vmslots);
 }
 // MemberName support
 // import sun_dyn_MemberName.*
 enum {
   IS_METHOD      = sun_dyn_MemberName::MN_IS_METHOD,
   IS_CONSTRUCTOR = sun_dyn_MemberName::MN_IS_CONSTRUCTOR,
   IS_FIELD       = sun_dyn_MemberName::MN_IS_FIELD,
   IS_TYPE        = sun_dyn_MemberName::MN_IS_TYPE,
   SEARCH_SUPERCLASSES = sun_dyn_MemberName::MN_SEARCH_SUPERCLASSES,
   SEARCH_INTERFACES   = sun_dyn_MemberName::MN_SEARCH_INTERFACES,
   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE,
   VM_INDEX_UNINITIALIZED = sun_dyn_MemberName::VM_INDEX_UNINITIALIZED
 };
 void MethodHandles::init_MemberName(oop mname_oop, oop target_oop) {
   if (target_oop->klass() == SystemDictionary::reflect_field_klass()) {
     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()
     int mods  = java_lang_reflect_Field::modifiers(target_oop);
     klassOop k = java_lang_Class::as_klassOop(clazz);
     int offset = instanceKlass::cast(k)->offset_from_fields(slot);
     init_MemberName(mname_oop, k, accessFlags_from(mods), offset);
   } else {
     int decode_flags = 0; klassOop receiver_limit = NULL;
     methodOop m = MethodHandles::decode_method(target_oop,
                                                receiver_limit, decode_flags);
     bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
     init_MemberName(mname_oop, m, do_dispatch);
   }
 }
 void MethodHandles::init_MemberName(oop mname_oop, methodOop m, bool do_dispatch) {
   int flags = ((m->is_initializer() ? IS_CONSTRUCTOR : IS_METHOD)
                | (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS ));
   oop vmtarget = m;
   int vmindex  = methodOopDesc::invalid_vtable_index;  // implies no info yet
   if (!do_dispatch || (flags & IS_CONSTRUCTOR) || m->can_be_statically_bound())
     vmindex = methodOopDesc::nonvirtual_vtable_index; // implies never any dispatch
   assert(vmindex != VM_INDEX_UNINITIALIZED, "Java sentinel value");
   sun_dyn_MemberName::set_vmtarget(mname_oop, vmtarget);
   sun_dyn_MemberName::set_vmindex(mname_oop,  vmindex);
   sun_dyn_MemberName::set_flags(mname_oop,    flags);
 }
 void MethodHandles::init_MemberName(oop mname_oop, klassOop field_holder, AccessFlags mods, int offset) {
   int flags = (IS_FIELD | (jushort)( mods.as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS ));
   oop vmtarget = field_holder;
   int vmindex  = offset;  // implies no info yet
   assert(vmindex != VM_INDEX_UNINITIALIZED, "bad alias on vmindex");
   sun_dyn_MemberName::set_vmtarget(mname_oop, vmtarget);
   sun_dyn_MemberName::set_vmindex(mname_oop,  vmindex);
   sun_dyn_MemberName::set_flags(mname_oop,    flags);
 }
 methodOop MethodHandles::decode_MemberName(oop mname, klassOop& receiver_limit_result, int& decode_flags_result) {
   int flags  = sun_dyn_MemberName::flags(mname);
   if ((flags & (IS_METHOD | IS_CONSTRUCTOR)) == 0)  return NULL;  // not invocable
   oop vmtarget = sun_dyn_MemberName::vmtarget(mname);
   int vmindex  = sun_dyn_MemberName::vmindex(mname);
   if (vmindex == VM_INDEX_UNINITIALIZED)  return NULL; // not resolved
   methodOop m = decode_vmtarget(vmtarget, vmindex, NULL, receiver_limit_result, decode_flags_result);
   oop clazz = sun_dyn_MemberName::clazz(mname);
   if (clazz != NULL && java_lang_Class::is_instance(clazz)) {
     klassOop klass = java_lang_Class::as_klassOop(clazz);
     if (klass != NULL)  receiver_limit_result = klass;
   }
   return m;
 }
 // An unresolved member name is a mere symbolic reference.
 // Resolving it plants a vmtarget/vmindex in it,
 // which refers dirctly to JVM internals.
 void MethodHandles::resolve_MemberName(Handle mname, TRAPS) {
   assert(sun_dyn_MemberName::is_instance(mname()), "");
 #ifdef ASSERT
   // If this assert throws, renegotiate the sentinel value used by the Java code,
   // so that it is distinct from any valid vtable index value, and any special
   // values defined in methodOopDesc::VtableIndexFlag.
   // The point of the slop is to give the Java code and the JVM some room
   // to independently specify sentinel values.
   const int sentinel_slop  = 10;
   const int sentinel_limit = methodOopDesc::highest_unused_vtable_index_value - sentinel_slop;
   assert(VM_INDEX_UNINITIALIZED < sentinel_limit, "Java sentinel != JVM sentinels");
 #endif
   if (sun_dyn_MemberName::vmindex(mname()) != VM_INDEX_UNINITIALIZED)
     return;  // already resolved
   oop defc_oop = sun_dyn_MemberName::clazz(mname());
   oop name_str = sun_dyn_MemberName::name(mname());
   oop type_str = sun_dyn_MemberName::type(mname());
   int flags    = sun_dyn_MemberName::flags(mname());
   if (defc_oop == NULL || name_str == NULL || type_str == NULL) {
     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve");
   }
   klassOop defc_klassOop = java_lang_Class::as_klassOop(defc_oop);
   defc_oop = NULL;  // safety
   if (defc_klassOop == NULL)  return;  // a primitive; no resolution possible
   if (!Klass::cast(defc_klassOop)->oop_is_instance()) {
     if (!Klass::cast(defc_klassOop)->oop_is_array())  return;
     defc_klassOop = SystemDictionary::object_klass();
   }
   instanceKlassHandle defc(THREAD, defc_klassOop);
   defc_klassOop = NULL;  // safety
   if (defc.is_null()) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), "primitive class");
   }
   defc->link_class(CHECK);
   // convert the external string name to an internal symbol
   symbolHandle name(THREAD, java_lang_String::as_symbol_or_null(name_str));
   if (name.is_null())  return;  // no such name
   name_str = NULL;  // safety
   // convert the external string or reflective type to an internal signature
   bool force_signature = (name() == vmSymbols::invoke_name());
   symbolHandle type; {
     symbolOop type_sym = NULL;
     if (java_dyn_MethodType::is_instance(type_str)) {
       type_sym = java_dyn_MethodType::as_signature(type_str, force_signature, CHECK);
     } else if (java_lang_Class::is_instance(type_str)) {
       type_sym = java_lang_Class::as_signature(type_str, force_signature, CHECK);
     } else if (java_lang_String::is_instance(type_str)) {
       if (force_signature) {
         type     = java_lang_String::as_symbol(type_str, CHECK);
       } else {
         type_sym = java_lang_String::as_symbol_or_null(type_str);
       }
     } else {
       THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized type");
     }
     if (type_sym != NULL)
       type = symbolHandle(THREAD, type_sym);
   }
   if (type.is_null())  return;  // no such signature exists in the VM
   type_str = NULL; // safety
   // Time to do the lookup.
   switch (flags & ALL_KINDS) {
   case IS_METHOD:
     {
       CallInfo result;
       {
         EXCEPTION_MARK;
         if ((flags & JVM_ACC_STATIC) != 0) {
           LinkResolver::resolve_static_call(result,
                         defc, name, type, KlassHandle(), false, false, THREAD);
         } else if (defc->is_interface()) {
           LinkResolver::resolve_interface_call(result, Handle(), defc,
                         defc, name, type, KlassHandle(), false, false, THREAD);
         } else {
           LinkResolver::resolve_virtual_call(result, Handle(), defc,
                         defc, name, type, KlassHandle(), false, false, THREAD);
         }
         if (HAS_PENDING_EXCEPTION) {
           CLEAR_PENDING_EXCEPTION;
           return;
         }
       }
       methodHandle m = result.resolved_method();
       oop vmtarget = NULL;
       int vmindex = methodOopDesc::nonvirtual_vtable_index;
       if (defc->is_interface()) {
         vmindex = klassItable::compute_itable_index(m());
         assert(vmindex >= 0, "");
       } else if (result.has_vtable_index()) {
         vmindex = result.vtable_index();
         assert(vmindex >= 0, "");
       }
       assert(vmindex != VM_INDEX_UNINITIALIZED, "");
       if (vmindex < 0) {
         assert(result.is_statically_bound(), "");
         vmtarget = m();
       } else {
         vmtarget = result.resolved_klass()->as_klassOop();
       }
       int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
       sun_dyn_MemberName::set_vmtarget(mname(), vmtarget);
       sun_dyn_MemberName::set_vmindex(mname(),  vmindex);
       sun_dyn_MemberName::set_modifiers(mname(), mods);
       DEBUG_ONLY(int junk; klassOop junk2);
       assert(decode_MemberName(mname(), junk2, junk) == result.resolved_method()(),
              "properly stored for later decoding");
       return;
     }
   case IS_CONSTRUCTOR:
     {
       CallInfo result;
       {
         EXCEPTION_MARK;
         if (name() == vmSymbols::object_initializer_name()) {
           LinkResolver::resolve_special_call(result,
                         defc, name, type, KlassHandle(), false, THREAD);
         } else {
           break;                // will throw after end of switch
         }
         if (HAS_PENDING_EXCEPTION) {
           CLEAR_PENDING_EXCEPTION;
           return;
         }
       }
       assert(result.is_statically_bound(), "");
       methodHandle m = result.resolved_method();
       oop vmtarget = m();
       int vmindex  = methodOopDesc::nonvirtual_vtable_index;
       int mods     = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
       sun_dyn_MemberName::set_vmtarget(mname(), vmtarget);
       sun_dyn_MemberName::set_vmindex(mname(),  vmindex);
       sun_dyn_MemberName::set_modifiers(mname(), mods);
       DEBUG_ONLY(int junk; klassOop junk2);
       assert(decode_MemberName(mname(), junk2, junk) == result.resolved_method()(),
              "properly stored for later decoding");
       return;
     }
   case IS_FIELD:
     {
       // This is taken from LinkResolver::resolve_field, sans access checks.
       fieldDescriptor fd; // find_field initializes fd if found
       KlassHandle sel_klass(THREAD, instanceKlass::cast(defc())->find_field(name(), type(), &fd));
       // check if field exists; i.e., if a klass containing the field def has been selected
       if (sel_klass.is_null())  return;
       oop vmtarget = sel_klass->as_klassOop();
       int vmindex  = fd.offset();
       int mods     = (fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS);
       if (vmindex == VM_INDEX_UNINITIALIZED)  break;  // should not happen
       sun_dyn_MemberName::set_vmtarget(mname(),  vmtarget);
       sun_dyn_MemberName::set_vmindex(mname(),   vmindex);
       sun_dyn_MemberName::set_modifiers(mname(), mods);
       return;
     }
   }
   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 }
 // Conversely, a member name which is only initialized from JVM internals
 // may have null defc, name, and type fields.
 // Resolving it plants a vmtarget/vmindex in it,
 // which refers directly to JVM internals.
 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
   assert(sun_dyn_MemberName::is_instance(mname()), "");
   oop vmtarget = sun_dyn_MemberName::vmtarget(mname());
   int vmindex  = sun_dyn_MemberName::vmindex(mname());
   if (vmtarget == NULL || vmindex == VM_INDEX_UNINITIALIZED) {
     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
   }
   bool have_defc = (sun_dyn_MemberName::clazz(mname()) != NULL);
   bool have_name = (sun_dyn_MemberName::name(mname()) != NULL);
   bool have_type = (sun_dyn_MemberName::type(mname()) != NULL);
   int flags      = sun_dyn_MemberName::flags(mname());
   if (suppress != 0) {
     if (suppress & _suppress_defc)  have_defc = true;
     if (suppress & _suppress_name)  have_name = true;
     if (suppress & _suppress_type)  have_type = true;
   }
   if (have_defc && have_name && have_type)  return;  // nothing needed
   switch (flags & ALL_KINDS) {
   case IS_METHOD:
   case IS_CONSTRUCTOR:
     {
       klassOop receiver_limit = NULL;
       int      decode_flags   = 0;
       methodHandle m(THREAD, decode_vmtarget(vmtarget, vmindex, NULL,
                                              receiver_limit, decode_flags));
       if (m.is_null())  break;
       if (!have_defc) {
         klassOop defc = m->method_holder();
         if (receiver_limit != NULL && receiver_limit != defc
             && Klass::cast(receiver_limit)->is_subtype_of(defc))
           defc = receiver_limit;
         sun_dyn_MemberName::set_clazz(mname(), Klass::cast(defc)->java_mirror());
       }
       if (!have_name) {
         //not java_lang_String::create_from_symbol; let's intern member names
         Handle name = StringTable::intern(m->name(), CHECK);
         sun_dyn_MemberName::set_name(mname(), name());
       }
       if (!have_type) {
         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
         sun_dyn_MemberName::set_type(mname(), type());
       }
       return;
     }
   case IS_FIELD:
     {
       // This is taken from LinkResolver::resolve_field, sans access checks.
       if (!vmtarget->is_klass())  break;
       if (!Klass::cast((klassOop) vmtarget)->oop_is_instance())  break;
       instanceKlassHandle defc(THREAD, (klassOop) vmtarget);
       bool is_static = ((flags & JVM_ACC_STATIC) != 0);
       fieldDescriptor fd; // find_field initializes fd if found
       if (!defc->find_field_from_offset(vmindex, is_static, &fd))
         break;                  // cannot expand
       if (!have_defc) {
         sun_dyn_MemberName::set_clazz(mname(), defc->java_mirror());
       }
       if (!have_name) {
         //not java_lang_String::create_from_symbol; let's intern member names
         Handle name = StringTable::intern(fd.name(), CHECK);
         sun_dyn_MemberName::set_name(mname(), name());
       }
       if (!have_type) {
         Handle type = java_lang_String::create_from_symbol(fd.signature(), CHECK);
         sun_dyn_MemberName::set_type(mname(), type());
       }
       return;
     }
   }
   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 }
 int MethodHandles::find_MemberNames(klassOop k,
                                     symbolOop name, symbolOop sig,
                                     int mflags, klassOop caller,
                                     int skip, objArrayOop results) {
   DEBUG_ONLY(No_Safepoint_Verifier nsv);
   // this code contains no safepoints!
   // %%% take caller into account!
   if (k == NULL || !Klass::cast(k)->oop_is_instance())  return -1;
   int rfill = 0, rlimit = results->length(), rskip = skip;
   // overflow measurement:
   int overflow = 0, overflow_limit = MAX2(1000, rlimit);
   int match_flags = mflags;
   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);
   bool local_only = !(search_superc | search_intfc);
   bool classes_only = false;
   if (name != NULL) {
     if (name->utf8_length() == 0)  return 0; // a match is not possible
   }
   if (sig != NULL) {
     if (sig->utf8_length() == 0)  return 0; // a match is not possible
     if (sig->byte_at(0) == '(')
       match_flags &= ~(IS_FIELD | IS_TYPE);
     else
       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
   }
   if ((match_flags & IS_TYPE) != 0) {
     // NYI, and Core Reflection works quite well for this query
   }
   if ((match_flags & IS_FIELD) != 0) {
     for (FieldStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
       if (name != NULL && st.name() != name)
           continue;
       if (sig != NULL && st.signature() != sig)
         continue;
       // passed the filters
       if (rskip > 0) {
         --rskip;
       } else if (rfill < rlimit) {
         oop result = results->obj_at(rfill++);
         if (!sun_dyn_MemberName::is_instance(result))
           return -99;  // caller bug!
         MethodHandles::init_MemberName(result, st.klass()->as_klassOop(), st.access_flags(), st.offset());
       } else if (++overflow >= overflow_limit) {
         match_flags = 0; break; // got tired of looking at overflow
       }
     }
   }
   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
     // watch out for these guys:
     symbolOop init_name   = vmSymbols::object_initializer_name();
     symbolOop clinit_name = vmSymbols::class_initializer_name();
     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>
     bool negate_name_test = false;
     // fix name so that it captures the intention of IS_CONSTRUCTOR
     if (!(match_flags & IS_METHOD)) {
       // constructors only
       if (name == NULL) {
         name = init_name;
       } else if (name != init_name) {
         return 0;               // no constructors of this method name
       }
     } else if (!(match_flags & IS_CONSTRUCTOR)) {
       // methods only
       if (name == NULL) {
         name = init_name;
         negate_name_test = true; // if we see the name, we *omit* the entry
       } else if (name == init_name) {
         return 0;               // no methods of this constructor name
       }
     } else {
       // caller will accept either sort; no need to adjust name
     }
     for (MethodStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
       methodOop m = st.method();
       symbolOop m_name = m->name();
       if (m_name == clinit_name)
         continue;
       if (name != NULL && ((m_name != name) ^ negate_name_test))
           continue;
       if (sig != NULL && m->signature() != sig)
         continue;
       // passed the filters
       if (rskip > 0) {
         --rskip;
       } else if (rfill < rlimit) {
         oop result = results->obj_at(rfill++);
         if (!sun_dyn_MemberName::is_instance(result))
           return -99;  // caller bug!
         MethodHandles::init_MemberName(result, m, true);
       } else if (++overflow >= overflow_limit) {
         match_flags = 0; break; // got tired of looking at overflow
       }
     }
   }
   // return number of elements we at leasted wanted to initialize
   return rfill + overflow;
 }
 // Decode the vmtarget field of a method handle.
 // Sanitize out methodOops, klassOops, and any other non-Java data.
 // This is for debugging and reflection.
 oop MethodHandles::encode_target(Handle mh, int format, TRAPS) {
   assert(java_dyn_MethodHandle::is_instance(mh()), "must be a MH");
   if (format == ETF_HANDLE_OR_METHOD_NAME) {
     oop target = java_dyn_MethodHandle::vmtarget(mh());
     if (target == NULL) {
       return NULL;                // unformed MH
     }
     klassOop tklass = target->klass();
     if (Klass::cast(tklass)->is_subclass_of(SystemDictionary::object_klass())) {
       return target;              // target is another MH (or something else?)
     }
   }
   if (format == ETF_DIRECT_HANDLE) {
     oop target = mh();
     for (;;) {
       if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
         return target;
       }
       if (!java_dyn_MethodHandle::is_instance(target)){
         return NULL;                // unformed MH
       }
       target = java_dyn_MethodHandle::vmtarget(target);
     }
   }
   // cases of metadata in MH.vmtarget:
   // - AMH can have methodOop for static invoke with bound receiver
   // - DMH can have methodOop for static invoke (on variable receiver)
   // - DMH can have klassOop for dispatched (non-static) invoke
   klassOop receiver_limit = NULL;
   int decode_flags = 0;
   methodOop m = decode_MethodHandle(mh(), receiver_limit, decode_flags);
   if (m == NULL)  return NULL;
   switch (format) {
   case ETF_REFLECT_METHOD:
     // same as jni_ToReflectedMethod:
     if (m->is_initializer()) {
       return Reflection::new_constructor(m, THREAD);
     } else {
       return Reflection::new_method(m, UseNewReflection, false, THREAD);
     }
   case ETF_HANDLE_OR_METHOD_NAME:   // method, not handle
   case ETF_METHOD_NAME:
     {
       if (SystemDictionary::MemberName_klass() == NULL)  break;
       instanceKlassHandle mname_klass(THREAD, SystemDictionary::MemberName_klass());
       mname_klass->initialize(CHECK_NULL);
       Handle mname = mname_klass->allocate_instance_handle(CHECK_NULL);
       sun_dyn_MemberName::set_vmindex(mname(), VM_INDEX_UNINITIALIZED);
       bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
       init_MemberName(mname(), m, do_dispatch);
       expand_MemberName(mname, 0, CHECK_NULL);
       return mname();
     }
   }
   // Unknown format code.
   char msg[50];
   jio_snprintf(msg, sizeof(msg), "unknown getTarget format=%d", format);
   THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), msg);
 }
 static const char* always_null_names[] = {
   "java/lang/Void",
   "java/lang/Null",
   //"java/lang/Nothing",
   "sun/dyn/empty/Empty",
   NULL
 };
 static bool is_always_null_type(klassOop klass) {
   if (!Klass::cast(klass)->oop_is_instance())  return false;
   instanceKlass* ik = instanceKlass::cast(klass);
   // Must be on the boot class path:
   if (ik->class_loader() != NULL)  return false;
   // Check the name.
   symbolOop name = ik->name();
   for (int i = 0; ; i++) {
     const char* test_name = always_null_names[i];
     if (test_name == NULL)  break;
     if (name->equals(test_name, (int) strlen(test_name)))
       return true;
   }
   return false;
 }
 bool MethodHandles::class_cast_needed(klassOop src, klassOop dst) {
   if (src == dst || dst == SystemDictionary::object_klass())
     return false;                               // quickest checks
   Klass* srck = Klass::cast(src);
   Klass* dstk = Klass::cast(dst);
   if (dstk->is_interface()) {
     // interface receivers can safely be viewed as untyped,
     // because interface calls always include a dynamic check
     //dstk = Klass::cast(SystemDictionary::object_klass());
     return false;
   }
   if (srck->is_interface()) {
     // interface arguments must be viewed as untyped
     //srck = Klass::cast(SystemDictionary::object_klass());
     return true;
   }
   if (is_always_null_type(src)) {
     // some source types are known to be never instantiated;
     // they represent references which are always null
     // such null references never fail to convert safely
     return false;
   }
   return !srck->is_subclass_of(dstk->as_klassOop());
 }
 static oop object_java_mirror() {
   return Klass::cast(SystemDictionary::object_klass())->java_mirror();
 }
 bool MethodHandles::same_basic_type_for_arguments(BasicType src,
                                                   BasicType dst,
                                                   bool raw,
                                                   bool for_return) {
   if (for_return) {
     // return values can always be forgotten:
     if (dst == T_VOID)  return true;
     if (src == T_VOID)  return raw && (dst == T_INT);
     // We allow caller to receive a garbage int, which is harmless.
     // This trick is pulled by trusted code (see VerifyType.canPassRaw).
   }
   assert(src != T_VOID && dst != T_VOID, "should not be here");
   if (src == dst)  return true;
   if (type2size[src] != type2size[dst])  return false;
   // allow reinterpretation casts for integral widening
   if (is_subword_type(src)) { // subwords can fit in int or other subwords
     if (dst == T_INT)         // any subword fits in an int
       return true;
     if (src == T_BOOLEAN)     // boolean fits in any subword
       return is_subword_type(dst);
     if (src == T_BYTE && dst == T_SHORT)
       return true;            // remaining case: byte fits in short
   }
   // allow float/fixed reinterpretation casts
   if (src == T_FLOAT)   return dst == T_INT;
   if (src == T_INT)     return dst == T_FLOAT;
   if (src == T_DOUBLE)  return dst == T_LONG;
   if (src == T_LONG)    return dst == T_DOUBLE;
   return false;
 }
 const char* MethodHandles::check_method_receiver(methodOop m,
                                                  klassOop passed_recv_type) {
   assert(!m->is_static(), "caller resp.");
   if (passed_recv_type == NULL)
     return "receiver type is primitive";
   if (class_cast_needed(passed_recv_type, m->method_holder())) {
     Klass* formal = Klass::cast(m->method_holder());
     return SharedRuntime::generate_class_cast_message("receiver type",
                                                       formal->external_name());
   }
   return NULL;                  // checks passed
 }
 // Verify that m's signature can be called type-safely by a method handle
 // of the given method type 'mtype'.
 // It takes a TRAPS argument because it must perform symbol lookups.
 void MethodHandles::verify_method_signature(methodHandle m,
                                             Handle mtype,
                                             int first_ptype_pos,
                                             KlassHandle insert_ptype,
                                             TRAPS) {
   objArrayHandle ptypes(THREAD, java_dyn_MethodType::ptypes(mtype()));
   int pnum = first_ptype_pos;
   int pmax = ptypes->length();
   int mnum = 0;                 // method argument
   const char* err = NULL;
   for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) {
     oop ptype_oop = NULL;
     if (ss.at_return_type()) {
       if (pnum != pmax)
         { err = "too many arguments"; break; }
       ptype_oop = java_dyn_MethodType::rtype(mtype());
     } else {
       if (pnum >= pmax)
         { err = "not enough arguments"; break; }
       if (pnum >= 0)
         ptype_oop = ptypes->obj_at(pnum);
       else if (insert_ptype.is_null())
         ptype_oop = NULL;
       else
         ptype_oop = insert_ptype->java_mirror();
       pnum += 1;
       mnum += 1;
     }
     klassOop  mklass = NULL;
     BasicType mtype  = ss.type();
     if (mtype == T_ARRAY)  mtype = T_OBJECT; // fold all refs to T_OBJECT
     if (mtype == T_OBJECT) {
       if (ptype_oop == NULL) {
         // null matches any reference
         continue;
       }
       // If we fail to resolve types at this point, we will throw an error.
       symbolOop    name_oop = ss.as_symbol(CHECK);
       symbolHandle name(THREAD, name_oop);
       instanceKlass* mk = instanceKlass::cast(m->method_holder());
       Handle loader(THREAD, mk->class_loader());
       Handle domain(THREAD, mk->protection_domain());
       mklass = SystemDictionary::resolve_or_fail(name, loader, domain,
                                                  true, CHECK);
     }
     if (ptype_oop == NULL) {
       // null does not match any non-reference; use Object to report the error
       ptype_oop = object_java_mirror();
     }
     klassOop  pklass = NULL;
     BasicType ptype  = java_lang_Class::as_BasicType(ptype_oop, &pklass);
     if (!ss.at_return_type()) {
       err = check_argument_type_change(ptype, pklass, mtype, mklass, mnum);
     } else {
       err = check_return_type_change(mtype, mklass, ptype, pklass); // note reversal!
     }
     if (err != NULL)  break;
   }
   if (err != NULL) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), err);
   }
 }
 // Main routine for verifying the MethodHandle.type of a proposed
 // direct or bound-direct method handle.
 void MethodHandles::verify_method_type(methodHandle m,
                                        Handle mtype,
                                        bool has_bound_recv,
                                        KlassHandle bound_recv_type,
                                        TRAPS) {
   bool m_needs_receiver = !m->is_static();
   const char* err = NULL;
   int first_ptype_pos = m_needs_receiver ? 1 : 0;
   if (has_bound_recv) {
     first_ptype_pos -= 1;  // ptypes do not include the bound argument; start earlier in them
     if (m_needs_receiver && bound_recv_type.is_null())
       { err = "bound receiver is not an object"; goto die; }
   }
   if (m_needs_receiver && err == NULL) {
     objArrayOop ptypes = java_dyn_MethodType::ptypes(mtype());
     if (ptypes->length() < first_ptype_pos)
       { err = "receiver argument is missing"; goto die; }
     if (has_bound_recv)
       err = check_method_receiver(m(), bound_recv_type->as_klassOop());
     else
       err = check_method_receiver(m(), java_lang_Class::as_klassOop(ptypes->obj_at(first_ptype_pos-1)));
     if (err != NULL)  goto die;
   }
   // Check the other arguments for mistypes.
   verify_method_signature(m, mtype, first_ptype_pos, bound_recv_type, CHECK);
   return;
  die:
   THROW_MSG(vmSymbols::java_lang_InternalError(), err);
 }
 void MethodHandles::verify_vmslots(Handle mh, TRAPS) {
   // Verify vmslots.
   int check_slots = argument_slot_count(java_dyn_MethodHandle::type(mh()));
   if (java_dyn_MethodHandle::vmslots(mh()) != check_slots) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH");
   }
 }
 void MethodHandles::verify_vmargslot(Handle mh, int argnum, int argslot, TRAPS) {
   // Verify that argslot points at the given argnum.
   int check_slot = argument_slot(java_dyn_MethodHandle::type(mh()), argnum);
   if (argslot != check_slot || argslot < 0) {
     const char* fmt = "for argnum of %d, vmargslot is %d, should be %d";
     size_t msglen = strlen(fmt) + 3*11 + 1;
     char* msg = NEW_RESOURCE_ARRAY(char, msglen);
     jio_snprintf(msg, msglen, fmt, argnum, argslot, check_slot);
     THROW_MSG(vmSymbols::java_lang_InternalError(), msg);
   }
 }
 // Verify the correspondence between two method types.
 // Apart from the advertised changes, caller method type X must
 // be able to invoke the callee method Y type with no violations
 // of type integrity.
 // Return NULL if all is well, else a short error message.
 const char* MethodHandles::check_method_type_change(oop src_mtype, int src_beg, int src_end,
                                                     int insert_argnum, oop insert_type,
                                                     int change_argnum, oop change_type,
                                                     int delete_argnum,
                                                     oop dst_mtype, int dst_beg, int dst_end,
                                                     bool raw) {
   objArrayOop src_ptypes = java_dyn_MethodType::ptypes(src_mtype);
   objArrayOop dst_ptypes = java_dyn_MethodType::ptypes(dst_mtype);
   int src_max = src_ptypes->length();
   int dst_max = dst_ptypes->length();
   if (src_end == -1)  src_end = src_max;
   if (dst_end == -1)  dst_end = dst_max;
   assert(0 <= src_beg && src_beg <= src_end && src_end <= src_max, "oob");
   assert(0 <= dst_beg && dst_beg <= dst_end && dst_end <= dst_max, "oob");
   // pending actions; set to -1 when done:
   int ins_idx = insert_argnum, chg_idx = change_argnum, del_idx = delete_argnum;
   const char* err = NULL;
   // Walk along each array of parameter types, including a virtual
   // NULL end marker at the end of each.
   for (int src_idx = src_beg, dst_idx = dst_beg;
        (src_idx <= src_end && dst_idx <= dst_end);
        src_idx++, dst_idx++) {
     oop src_type = (src_idx == src_end) ? oop(NULL) : src_ptypes->obj_at(src_idx);
     oop dst_type = (dst_idx == dst_end) ? oop(NULL) : dst_ptypes->obj_at(dst_idx);
     bool fix_null_src_type = false;
     // Perform requested edits.
     if (ins_idx == src_idx) {
       // note that the inserted guy is never affected by a change or deletion
       ins_idx = -1;
       src_type = insert_type;
       fix_null_src_type = true;
       --src_idx;                // back up to process src type on next loop
       src_idx = src_end;
     } else {
       // note that the changed guy can be immediately deleted
       if (chg_idx == src_idx) {
         chg_idx = -1;
         assert(src_idx < src_end, "oob");
         src_type = change_type;
         fix_null_src_type = true;
       }
       if (del_idx == src_idx) {
         del_idx = -1;
         assert(src_idx < src_end, "oob");
         --dst_idx;
         continue;               // rerun loop after skipping this position
       }
     }
     if (src_type == NULL && fix_null_src_type)
       // explicit null in this case matches any dest reference
       src_type = (java_lang_Class::is_primitive(dst_type) ? object_java_mirror() : dst_type);
     // Compare the two argument types.
     if (src_type != dst_type) {
       if (src_type == NULL)  return "not enough arguments";
       if (dst_type == NULL)  return "too many arguments";
       err = check_argument_type_change(src_type, dst_type, dst_idx, raw);
       if (err != NULL)  return err;
     }
   }
   // Now compare return types also.
   oop src_rtype = java_dyn_MethodType::rtype(src_mtype);
   oop dst_rtype = java_dyn_MethodType::rtype(dst_mtype);
   if (src_rtype != dst_rtype) {
     err = check_return_type_change(dst_rtype, src_rtype, raw); // note reversal!
     if (err != NULL)  return err;
   }
   assert(err == NULL, "");
   return NULL;  // all is well
 }
 const char* MethodHandles::check_argument_type_change(BasicType src_type,
                                                       klassOop src_klass,
                                                       BasicType dst_type,
                                                       klassOop dst_klass,
                                                       int argnum,
                                                       bool raw) {
   const char* err = NULL;
   bool for_return = (argnum < 0);
   // just in case:
   if (src_type == T_ARRAY)  src_type = T_OBJECT;
   if (dst_type == T_ARRAY)  dst_type = T_OBJECT;
   // Produce some nice messages if VerifyMethodHandles is turned on:
   if (!same_basic_type_for_arguments(src_type, dst_type, raw, for_return)) {
     if (src_type == T_OBJECT) {
       if (raw && dst_type == T_INT && is_always_null_type(src_klass))
         return NULL;    // OK to convert a null pointer to a garbage int
       err = ((argnum >= 0)
              ? "type mismatch: passing a %s for method argument #%d, which expects primitive %s"
              : "type mismatch: returning a %s, but caller expects primitive %s");
     } else if (dst_type == T_OBJECT) {
       err = ((argnum >= 0)
              ? "type mismatch: passing a primitive %s for method argument #%d, which expects %s"
              : "type mismatch: returning a primitive %s, but caller expects %s");
     } else {
       err = ((argnum >= 0)
              ? "type mismatch: passing a %s for method argument #%d, which expects %s"
              : "type mismatch: returning a %s, but caller expects %s");
     }
   } else if (src_type == T_OBJECT && dst_type == T_OBJECT &&
              class_cast_needed(src_klass, dst_klass)) {
     if (!class_cast_needed(dst_klass, src_klass)) {
       if (raw)
         return NULL;    // reverse cast is OK; the MH target is trusted to enforce it
       err = ((argnum >= 0)
              ? "cast required: passing a %s for method argument #%d, which expects %s"
              : "cast required: returning a %s, but caller expects %s");
     } else {
       err = ((argnum >= 0)
              ? "reference mismatch: passing a %s for method argument #%d, which expects %s"
              : "reference mismatch: returning a %s, but caller expects %s");
     }
   } else {
     // passed the obstacle course
     return NULL;
   }
   // format, format, format
   const char* src_name = type2name(src_type);
   const char* dst_name = type2name(dst_type);
   if (src_type == T_OBJECT)  src_name = Klass::cast(src_klass)->external_name();
   if (dst_type == T_OBJECT)  dst_name = Klass::cast(dst_klass)->external_name();
   if (src_name == NULL)  src_name = "unknown type";
   if (dst_name == NULL)  dst_name = "unknown type";
   size_t msglen = strlen(err) + strlen(src_name) + strlen(dst_name) + (argnum < 10 ? 1 : 11);
   char* msg = NEW_RESOURCE_ARRAY(char, msglen + 1);
   if (argnum >= 0) {
     assert(strstr(err, "%d") != NULL, "");
     jio_snprintf(msg, msglen, err, src_name, argnum, dst_name);
   } else {
     assert(strstr(err, "%d") == NULL, "");
     jio_snprintf(msg, msglen, err, src_name,         dst_name);
   }
   return msg;
 }
 // Compute the depth within the stack of the given argument, i.e.,
 // the combined size of arguments to the right of the given argument.
 // For the last argument (ptypes.length-1) this will be zero.
 // For the first argument (0) this will be the size of all
 // arguments but that one.  For the special number -1, this
 // will be the size of all arguments, including the first.
 // If the argument is neither -1 nor a valid argument index,
 // then return a negative number.  Otherwise, the result
 // is in the range [0..vmslots] inclusive.
 int MethodHandles::argument_slot(oop method_type, int arg) {
   objArrayOop ptypes = java_dyn_MethodType::ptypes(method_type);
   int argslot = 0;
   int len = ptypes->length();
   if (arg < -1 || arg >= len)  return -99;
   for (int i = len-1; i > arg; i--) {
     BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
     argslot += type2size[bt];
   }
   assert(argument_slot_to_argnum(method_type, argslot) == arg, "inverse works");
   return argslot;
 }
 // Given a slot number, return the argument number.
 int MethodHandles::argument_slot_to_argnum(oop method_type, int query_argslot) {
   objArrayOop ptypes = java_dyn_MethodType::ptypes(method_type);
   int argslot = 0;
   int len = ptypes->length();
   for (int i = len-1; i >= 0; i--) {
     if (query_argslot == argslot)  return i;
     BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
     argslot += type2size[bt];
   }
   // return pseudo-arg deepest in stack:
   if (query_argslot == argslot)  return -1;
   return -99;                   // oob slot, or splitting a double-slot arg
 }
 methodHandle MethodHandles::dispatch_decoded_method(methodHandle m,
                                                     KlassHandle receiver_limit,
                                                     int decode_flags,
                                                     KlassHandle receiver_klass,
                                                     TRAPS) {
   assert((decode_flags & ~_DMF_DIRECT_MASK) == 0, "must be direct method reference");
   assert((decode_flags & _dmf_has_receiver) != 0, "must have a receiver or first reference argument");
   if (!m->is_static() &&
       (receiver_klass.is_null() || !receiver_klass->is_subtype_of(m->method_holder())))
     // given type does not match class of method, or receiver is null!
     // caller should have checked this, but let's be extra careful...
     return methodHandle();
   if (receiver_limit.not_null() &&
       (receiver_klass.not_null() && !receiver_klass->is_subtype_of(receiver_limit())))
     // given type is not limited to the receiver type
     // note that a null receiver can match any reference value, for a static method
     return methodHandle();
   if (!(decode_flags & MethodHandles::_dmf_does_dispatch)) {
     // pre-dispatched or static method (null receiver is OK for static)
     return m;
   } else if (receiver_klass.is_null()) {
     // null receiver value; cannot dispatch
     return methodHandle();
   } else if (!(decode_flags & MethodHandles::_dmf_from_interface)) {
     // perform virtual dispatch
     int vtable_index = m->vtable_index();
     guarantee(vtable_index >= 0, "valid vtable index");
     // receiver_klass might be an arrayKlassOop but all vtables start at
     // the same place. The cast is to avoid virtual call and assertion.
     // See also LinkResolver::runtime_resolve_virtual_method.
     instanceKlass* inst = (instanceKlass*)Klass::cast(receiver_klass());
     DEBUG_ONLY(inst->verify_vtable_index(vtable_index));
     methodOop m_oop = inst->method_at_vtable(vtable_index);
     return methodHandle(THREAD, m_oop);
   } else {
     // perform interface dispatch
     int itable_index = klassItable::compute_itable_index(m());
     guarantee(itable_index >= 0, "valid itable index");
     instanceKlass* inst = instanceKlass::cast(receiver_klass());
     methodOop m_oop = inst->method_at_itable(m->method_holder(), itable_index, THREAD);
     return methodHandle(THREAD, m_oop);
   }
 }
 void MethodHandles::verify_DirectMethodHandle(Handle mh, methodHandle m, TRAPS) {
   // Verify type.
   Handle mtype(THREAD, java_dyn_MethodHandle::type(mh()));
   verify_method_type(m, mtype, false, KlassHandle(), CHECK);
   // Verify vmslots.
   if (java_dyn_MethodHandle::vmslots(mh()) != m->size_of_parameters()) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in DMH");
   }
 }
 void MethodHandles::init_DirectMethodHandle(Handle mh, methodHandle m, bool do_dispatch, TRAPS) {
   // Check arguments.
   if (mh.is_null() || m.is_null() ||
       (!do_dispatch && m->is_abstract())) {
     THROW(vmSymbols::java_lang_InternalError());
   }
   java_dyn_MethodHandle::init_vmslots(mh());
   if (VerifyMethodHandles) {
     // The privileged code which invokes this routine should not make
     // a mistake about types, but it's better to verify.
     verify_DirectMethodHandle(mh, m, CHECK);
   }
   // Finally, after safety checks are done, link to the target method.
   // We will follow the same path as the latter part of
   // InterpreterRuntime::resolve_invoke(), which first finds the method
   // and then decides how to populate the constant pool cache entry
   // that links the interpreter calls to the method.  We need the same
   // bits, and will use the same calling sequence code.
   int vmindex = methodOopDesc::garbage_vtable_index;
   oop vmtarget = NULL;
   instanceKlass::cast(m->method_holder())->link_class(CHECK);
   MethodHandleEntry* me = NULL;
   if (do_dispatch && Klass::cast(m->method_holder())->is_interface()) {
     // We are simulating an invokeinterface instruction.
     // (We might also be simulating an invokevirtual on a miranda method,
     // but it is safe to treat it as an invokeinterface.)
     assert(!m->can_be_statically_bound(), "no final methods on interfaces");
     vmindex = klassItable::compute_itable_index(m());
     assert(vmindex >= 0, "(>=0) == do_dispatch");
     // Set up same bits as ConstantPoolCacheEntry::set_interface_call().
     vmtarget = m->method_holder(); // the interface
     me = MethodHandles::entry(MethodHandles::_invokeinterface_mh);
   } else if (!do_dispatch || m->can_be_statically_bound()) {
     // We are simulating an invokestatic or invokespecial instruction.
     // Set up the method pointer, just like ConstantPoolCacheEntry::set_method().
     vmtarget = m();
     // this does not help dispatch, but it will make it possible to parse this MH:
     vmindex  = methodOopDesc::nonvirtual_vtable_index;
     assert(vmindex < 0, "(>=0) == do_dispatch");
     if (!m->is_static()) {
       me = MethodHandles::entry(MethodHandles::_invokespecial_mh);
     } else {
       me = MethodHandles::entry(MethodHandles::_invokestatic_mh);
       // Part of the semantics of a static call is an initialization barrier.
       // For a DMH, it is done now, when the handle is created.
       Klass* k = Klass::cast(m->method_holder());
       if (k->should_be_initialized()) {
         k->initialize(CHECK);
       }
     }
   } else {
     // We are simulating an invokevirtual instruction.
     // Set up the vtable index, just like ConstantPoolCacheEntry::set_method().
     // The key logic is LinkResolver::runtime_resolve_virtual_method.
     vmindex  = m->vtable_index();
     vmtarget = m->method_holder();
     me = MethodHandles::entry(MethodHandles::_invokevirtual_mh);
   }
   if (me == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   sun_dyn_DirectMethodHandle::set_vmtarget(mh(), vmtarget);
   sun_dyn_DirectMethodHandle::set_vmindex(mh(),  vmindex);
   DEBUG_ONLY(int flags; klassOop rlimit);
   assert(MethodHandles::decode_method(mh(), rlimit, flags) == m(),
          "properly stored for later decoding");
   DEBUG_ONLY(bool actual_do_dispatch = ((flags & _dmf_does_dispatch) != 0));
   assert(!(actual_do_dispatch && !do_dispatch),
          "do not perform dispatch if !do_dispatch specified");
   assert(actual_do_dispatch == (vmindex >= 0), "proper later decoding of do_dispatch");
   assert(decode_MethodHandle_stack_pushes(mh()) == 0, "DMH does not move stack");
   // Done!
   java_dyn_MethodHandle::set_vmentry(mh(), me);
 }
 void MethodHandles::verify_BoundMethodHandle_with_receiver(Handle mh,
                                                            methodHandle m,
                                                            TRAPS) {
   // Verify type.
   oop receiver = sun_dyn_BoundMethodHandle::argument(mh());
   Handle mtype(THREAD, java_dyn_MethodHandle::type(mh()));
   KlassHandle bound_recv_type;
   if (receiver != NULL)  bound_recv_type = KlassHandle(THREAD, receiver->klass());
   verify_method_type(m, mtype, true, bound_recv_type, CHECK);
   int receiver_pos = m->size_of_parameters() - 1;
   // Verify MH.vmargslot, which should point at the bound receiver.
   verify_vmargslot(mh, -1, sun_dyn_BoundMethodHandle::vmargslot(mh()), CHECK);
   //verify_vmslots(mh, CHECK);
   // Verify vmslots.
   if (java_dyn_MethodHandle::vmslots(mh()) != receiver_pos) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH (receiver)");
   }
 }
 // Initialize a BMH with a receiver bound directly to a methodOop.
 void MethodHandles::init_BoundMethodHandle_with_receiver(Handle mh,
                                                          methodHandle original_m,
                                                          KlassHandle receiver_limit,
                                                          int decode_flags,
                                                          TRAPS) {
   // Check arguments.
   if (mh.is_null() || original_m.is_null()) {
     THROW(vmSymbols::java_lang_InternalError());
   }
   KlassHandle receiver_klass;
   {
     oop receiver_oop = sun_dyn_BoundMethodHandle::argument(mh());
     if (receiver_oop != NULL)
       receiver_klass = KlassHandle(THREAD, receiver_oop->klass());
   }
   methodHandle m = dispatch_decoded_method(original_m,
                                            receiver_limit, decode_flags,
                                            receiver_klass,
                                            CHECK);
   if (m.is_null())      { THROW(vmSymbols::java_lang_InternalError()); }
   if (m->is_abstract()) { THROW(vmSymbols::java_lang_AbstractMethodError()); }
   java_dyn_MethodHandle::init_vmslots(mh());
   if (VerifyMethodHandles) {
     verify_BoundMethodHandle_with_receiver(mh, m, CHECK);
   }
   sun_dyn_BoundMethodHandle::set_vmtarget(mh(), m());
   DEBUG_ONLY(int junk; klassOop junk2);
   assert(MethodHandles::decode_method(mh(), junk2, junk) == m(), "properly stored for later decoding");
   assert(decode_MethodHandle_stack_pushes(mh()) == 1, "BMH pushes one stack slot");
   // Done!
   java_dyn_MethodHandle::set_vmentry(mh(), MethodHandles::entry(MethodHandles::_bound_ref_direct_mh));
 }
 void MethodHandles::verify_BoundMethodHandle(Handle mh, Handle target, int argnum,
                                              bool direct_to_method, TRAPS) {
   Handle ptype_handle(THREAD,
                            java_dyn_MethodType::ptype(java_dyn_MethodHandle::type(target()), argnum));
   KlassHandle ptype_klass;
   BasicType ptype = java_lang_Class::as_BasicType(ptype_handle(), &ptype_klass);
   int slots_pushed = type2size[ptype];
   oop argument = sun_dyn_BoundMethodHandle::argument(mh());
   const char* err = NULL;
   switch (ptype) {
   case T_OBJECT:
     if (argument != NULL)
       // we must implicitly convert from the arg type to the outgoing ptype
       err = check_argument_type_change(T_OBJECT, argument->klass(), ptype, ptype_klass(), argnum);
     break;
   case T_ARRAY: case T_VOID:
     assert(false, "array, void do not appear here");
   default:
     if (ptype != T_INT && !is_subword_type(ptype)) {
       err = "unexpected parameter type";
       break;
     }
     // check subrange of Integer.value, if necessary
     if (argument == NULL || argument->klass() != SystemDictionary::int_klass()) {
       err = "bound integer argument must be of type java.lang.Integer";
       break;
     }
     if (ptype != T_INT) {
       int value_offset = java_lang_boxing_object::value_offset_in_bytes(T_INT);
       jint value = argument->int_field(value_offset);
       int vminfo = adapter_subword_vminfo(ptype);
       jint subword = truncate_subword_from_vminfo(value, vminfo);
       if (value != subword) {
         err = "bound subword value does not fit into the subword type";
         break;
       }
     }
     break;
   case T_FLOAT:
   case T_DOUBLE:
   case T_LONG:
     {
       // we must implicitly convert from the unboxed arg type to the outgoing ptype
       BasicType argbox = java_lang_boxing_object::basic_type(argument);
       if (argbox != ptype) {
         err = check_argument_type_change(T_OBJECT, (argument == NULL
                                                     ? SystemDictionary::object_klass()
                                                     : argument->klass()),
                                          ptype, ptype_klass(), argnum);
         assert(err != NULL, "this must be an error");
       }
       break;
     }
   }
   if (err == NULL) {
     DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
     if (direct_to_method) {
       assert(this_pushes == slots_pushed, "BMH pushes one or two stack slots");
       assert(slots_pushed <= MethodHandlePushLimit, "");
     } else {
       int target_pushes = decode_MethodHandle_stack_pushes(target());
       assert(this_pushes == slots_pushed + target_pushes, "BMH stack motion must be correct");
       // do not blow the stack; use a Java-based adapter if this limit is exceeded
       if (slots_pushed + target_pushes > MethodHandlePushLimit)
         err = "too many bound parameters";
     }
   }
   if (err == NULL) {
     // Verify the rest of the method type.
     err = check_method_type_insertion(java_dyn_MethodHandle::type(mh()),
                                       argnum, ptype_handle(),
                                       java_dyn_MethodHandle::type(target()));
   }
   if (err != NULL) {
     THROW_MSG(vmSymbols::java_lang_InternalError(), err);
   }
 }
 void MethodHandles::init_BoundMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
   // Check arguments.
   if (mh.is_null() || target.is_null() || !java_dyn_MethodHandle::is_instance(target())) {
     THROW(vmSymbols::java_lang_InternalError());
   }
   java_dyn_MethodHandle::init_vmslots(mh());
   if (VerifyMethodHandles) {
     int insert_after = argnum - 1;
     verify_vmargslot(mh, insert_after, sun_dyn_BoundMethodHandle::vmargslot(mh()), CHECK);
     verify_vmslots(mh, CHECK);
   }
   // If (a) the target is a direct non-dispatched method handle,
   // or (b) the target is a dispatched direct method handle and we
   // are binding the receiver, cut out the middle-man.
   // Do this by decoding the DMH and using its methodOop directly as vmtarget.
   bool direct_to_method = false;
   if (OptimizeMethodHandles &&
       target->klass() == SystemDictionary::DirectMethodHandle_klass() &&
       (argnum == 0 || sun_dyn_DirectMethodHandle::vmindex(target()) < 0)) {
     int decode_flags = 0; klassOop receiver_limit_oop = NULL;
     methodHandle m(THREAD, decode_method(target(), receiver_limit_oop, decode_flags));
     if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "DMH failed to decode"); }
     DEBUG_ONLY(int m_vmslots = m->size_of_parameters() - 1); // pos. of 1st arg.
     assert(sun_dyn_BoundMethodHandle::vmslots(mh()) == m_vmslots, "type w/ m sig");
     if (argnum == 0 && (decode_flags & _dmf_has_receiver) != 0) {
       KlassHandle receiver_limit(THREAD, receiver_limit_oop);
       init_BoundMethodHandle_with_receiver(mh, m,
                                            receiver_limit, decode_flags,
                                            CHECK);
       return;
     }
     // Even if it is not a bound receiver, we still might be able
     // to bind another argument and still invoke the methodOop directly.
     if (!(decode_flags & _dmf_does_dispatch)) {
       direct_to_method = true;
       sun_dyn_BoundMethodHandle::set_vmtarget(mh(), m());
     }
   }
   if (!direct_to_method)
     sun_dyn_BoundMethodHandle::set_vmtarget(mh(), target());
   if (VerifyMethodHandles) {
     verify_BoundMethodHandle(mh, target, argnum, direct_to_method, CHECK);
   }
   // Next question:  Is this a ref, int, or long bound value?
   oop ptype_oop = java_dyn_MethodType::ptype(java_dyn_MethodHandle::type(target()), argnum);
   BasicType ptype = java_lang_Class::as_BasicType(ptype_oop);
   int slots_pushed = type2size[ptype];
   MethodHandleEntry* me = NULL;
   if (ptype == T_OBJECT) {
     if (direct_to_method)  me = MethodHandles::entry(_bound_ref_direct_mh);
     else                   me = MethodHandles::entry(_bound_ref_mh);
   } else if (slots_pushed == 2) {
     if (direct_to_method)  me = MethodHandles::entry(_bound_long_direct_mh);
     else                   me = MethodHandles::entry(_bound_long_mh);
   } else if (slots_pushed == 1) {
     if (direct_to_method)  me = MethodHandles::entry(_bound_int_direct_mh);
     else                   me = MethodHandles::entry(_bound_int_mh);
   } else {
     assert(false, "");
   }
   // Done!
   java_dyn_MethodHandle::set_vmentry(mh(), me);
 }
 static void throw_InternalError_for_bad_conversion(int conversion, const char* err, TRAPS) {
   char msg[200];
   jio_snprintf(msg, sizeof(msg), "bad adapter (conversion=0x%08x): %s", conversion, err);
   THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), msg);
 }
 void MethodHandles::verify_AdapterMethodHandle(Handle mh, int argnum, TRAPS) {
   jint conversion = sun_dyn_AdapterMethodHandle::conversion(mh());
   int  argslot    = sun_dyn_AdapterMethodHandle::vmargslot(mh());
   verify_vmargslot(mh, argnum, argslot, CHECK);
   verify_vmslots(mh, CHECK);
   jint conv_op    = adapter_conversion_op(conversion);
   if (!conv_op_valid(conv_op)) {
     throw_InternalError_for_bad_conversion(conversion, "unknown conversion op", THREAD);
     return;
   }
   EntryKind ek = adapter_entry_kind(conv_op);
   int stack_move = adapter_conversion_stack_move(conversion);
   BasicType src  = adapter_conversion_src_type(conversion);
   BasicType dest = adapter_conversion_dest_type(conversion);
   int vminfo     = adapter_conversion_vminfo(conversion); // should be zero
   Handle argument(THREAD,  sun_dyn_AdapterMethodHandle::argument(mh()));
   Handle target(THREAD,    sun_dyn_AdapterMethodHandle::vmtarget(mh()));
   Handle src_mtype(THREAD, java_dyn_MethodHandle::type(mh()));
   Handle dst_mtype(THREAD, java_dyn_MethodHandle::type(target()));
   const char* err = NULL;
   if (err == NULL) {
     // Check that the correct argument is supplied, but only if it is required.
     switch (ek) {
     case _adapter_check_cast:     // target type of cast
     case _adapter_ref_to_prim:    // wrapper type from which to unbox
     case _adapter_prim_to_ref:    // wrapper type to box into
     case _adapter_collect_args:   // array type to collect into
     case _adapter_spread_args:    // array type to spread from
       if (!java_lang_Class::is_instance(argument())
           || java_lang_Class::is_primitive(argument()))
         { err = "adapter requires argument of type java.lang.Class"; break; }
       if (ek == _adapter_collect_args ||
           ek == _adapter_spread_args) {
         // Make sure it is a suitable collection type.  (Array, for now.)
         Klass* ak = Klass::cast(java_lang_Class::as_klassOop(argument()));
         if (!ak->oop_is_objArray()) {
           { err = "adapter requires argument of type java.lang.Class<Object[]>"; break; }
         }
       }
       break;
     case _adapter_flyby:
     case _adapter_ricochet:
       if (!java_dyn_MethodHandle::is_instance(argument()))
         { err = "MethodHandle adapter argument required"; break; }
       break;
     default:
       if (argument.not_null())
         { err = "adapter has spurious argument"; break; }
       break;
     }
   }
   if (err == NULL) {
     // Check that the src/dest types are supplied if needed.
     switch (ek) {
     case _adapter_check_cast:
       if (src != T_OBJECT || dest != T_OBJECT) {
         err = "adapter requires object src/dest conversion subfields";
       }
       break;
     case _adapter_prim_to_prim:
       if (!is_java_primitive(src) || !is_java_primitive(dest) || src == dest) {
         err = "adapter requires primitive src/dest conversion subfields"; break;
       }
       if ( (src == T_FLOAT || src == T_DOUBLE) && !(dest == T_FLOAT || dest == T_DOUBLE) ||
           !(src == T_FLOAT || src == T_DOUBLE) &&  (dest == T_FLOAT || dest == T_DOUBLE)) {
         err = "adapter cannot convert beween floating and fixed-point"; break;
       }
       break;
     case _adapter_ref_to_prim:
       if (src != T_OBJECT || !is_java_primitive(dest)
           || argument() != Klass::cast(SystemDictionary::box_klass(dest))->java_mirror()) {
         err = "adapter requires primitive dest conversion subfield"; break;
       }
       break;
     case _adapter_prim_to_ref:
       if (!is_java_primitive(src) || dest != T_OBJECT
           || argument() != Klass::cast(SystemDictionary::box_klass(src))->java_mirror()) {
         err = "adapter requires primitive src conversion subfield"; break;
       }
       break;
     case _adapter_swap_args:
     case _adapter_rot_args:
       {
         if (!src || src != dest) {
           err = "adapter requires src/dest conversion subfields for swap"; break;
         }
         int swap_size = type2size[src];
         oop src_mtype  = sun_dyn_AdapterMethodHandle::type(mh());
         oop dest_mtype = sun_dyn_AdapterMethodHandle::type(target());
         int slot_limit = sun_dyn_AdapterMethodHandle::vmslots(target());
         int src_slot   = argslot;
         int dest_slot  = vminfo;
         bool rotate_up = (src_slot > dest_slot); // upward rotation
         int src_arg    = argnum;
         int dest_arg   = argument_slot_to_argnum(dest_mtype, dest_slot);
         verify_vmargslot(mh, dest_arg, dest_slot, CHECK);
         if (!(dest_slot >= src_slot + swap_size) &&
             !(src_slot >= dest_slot + swap_size)) {
           err = "source, destination slots must be distinct";
         } else if (ek == _adapter_swap_args && !(src_slot > dest_slot)) {
           err = "source of swap must be deeper in stack";
         } else if (ek == _adapter_swap_args) {
           err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, dest_arg),
                                            java_dyn_MethodType::ptype(dest_mtype, src_arg),
                                            dest_arg);
         } else if (ek == _adapter_rot_args) {
           if (rotate_up) {
             assert((src_slot > dest_slot) && (src_arg < dest_arg), "");
             // rotate up: [dest_slot..src_slot-ss] --> [dest_slot+ss..src_slot]
             // that is:   [src_arg+1..dest_arg] --> [src_arg..dest_arg-1]
             for (int i = src_arg+1; i <= dest_arg && err == NULL; i++) {
               err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, i),
                                                java_dyn_MethodType::ptype(dest_mtype, i-1),
                                                i);
             }
           } else { // rotate down
             assert((src_slot < dest_slot) && (src_arg > dest_arg), "");
             // rotate down: [src_slot+ss..dest_slot] --> [src_slot..dest_slot-ss]
             // that is:     [dest_arg..src_arg-1] --> [dst_arg+1..src_arg]
             for (int i = dest_arg; i <= src_arg-1 && err == NULL; i++) {
               err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, i),
                                                java_dyn_MethodType::ptype(dest_mtype, i+1),
                                                i);
             }
           }
         }
         if (err == NULL)
           err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, src_arg),
                                            java_dyn_MethodType::ptype(dest_mtype, dest_arg),
                                            src_arg);
       }
       break;
     case _adapter_collect_args:
     case _adapter_spread_args:
       {
         BasicType coll_type = (ek == _adapter_collect_args) ? dest : src;
         BasicType elem_type = (ek == _adapter_collect_args) ? src : dest;
         if (coll_type != T_OBJECT || elem_type != T_OBJECT) {
           err = "adapter requires src/dest subfields"; break;
           // later:
           // - consider making coll be a primitive array
           // - consider making coll be a heterogeneous collection
         }
       }
       break;
     default:
       if (src != 0 || dest != 0) {
         err = "adapter has spurious src/dest conversion subfields"; break;
       }
       break;
     }
   }
   if (err == NULL) {
     // Check the stack_move subfield.
     // It must always report the net change in stack size, positive or negative.
     int slots_pushed = stack_move / stack_move_unit();
     switch (ek) {
     case _adapter_prim_to_prim:
     case _adapter_ref_to_prim:
     case _adapter_prim_to_ref:
       if (slots_pushed != type2size[dest] - type2size[src]) {
         err = "wrong stack motion for primitive conversion";
       }
       break;
     case _adapter_dup_args:
       if (slots_pushed <= 0) {
         err = "adapter requires conversion subfield slots_pushed > 0";
       }
       break;
     case _adapter_drop_args:
       if (slots_pushed >= 0) {
         err = "adapter requires conversion subfield slots_pushed < 0";
       }
       break;
     case _adapter_collect_args:
       if (slots_pushed > 1) {
         err = "adapter requires conversion subfield slots_pushed <= 1";
       }
       break;
     case _adapter_spread_args:
       if (slots_pushed < -1) {
         err = "adapter requires conversion subfield slots_pushed >= -1";
       }
       break;
     default:
       if (stack_move != 0) {
         err = "adapter has spurious stack_move conversion subfield";
       }
       break;
     }
     if (err == NULL && stack_move != slots_pushed * stack_move_unit()) {
       err = "stack_move conversion subfield must be multiple of stack_move_unit";
     }
   }
   if (err == NULL) {
     // Make sure this adapter does not push too deeply.
     int slots_pushed = stack_move / stack_move_unit();
     int this_vmslots = java_dyn_MethodHandle::vmslots(mh());
     int target_vmslots = java_dyn_MethodHandle::vmslots(target());
     if (slots_pushed != (target_vmslots - this_vmslots)) {
       err = "stack_move inconsistent with previous and current MethodType vmslots";
     } else if (slots_pushed > 0)  {
       // verify stack_move against MethodHandlePushLimit
       int target_pushes = decode_MethodHandle_stack_pushes(target());
       // do not blow the stack; use a Java-based adapter if this limit is exceeded
       if (slots_pushed + target_pushes > MethodHandlePushLimit) {
         err = "adapter pushes too many parameters";
       }
     }
     // While we're at it, check that the stack motion decoder works:
     DEBUG_ONLY(int target_pushes = decode_MethodHandle_stack_pushes(target()));
     DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
     assert(this_pushes == slots_pushed + target_pushes, "AMH stack motion must be correct");
   }
   if (err == NULL && vminfo != 0) {
     switch (ek) {
       case _adapter_swap_args:
       case _adapter_rot_args:
         break;                // OK
     default:
       err = "vminfo subfield is reserved to the JVM";
     }
   }
   // Do additional ad hoc checks.
   if (err == NULL) {
     switch (ek) {
     case _adapter_retype_only:
       err = check_method_type_passthrough(src_mtype(), dst_mtype(), false);
       break;
     case _adapter_retype_raw:
       err = check_method_type_passthrough(src_mtype(), dst_mtype(), true);
       break;
     case _adapter_check_cast:
       {
         // The actual value being checked must be a reference:
         err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype(), argnum),
                                          object_java_mirror(), argnum);
         if (err != NULL)  break;
         // The output of the cast must fit with the destination argument:
         Handle cast_class = argument;
         err = check_method_type_conversion(src_mtype(),
                                            argnum, cast_class(),
                                            dst_mtype());
       }
       break;
       // %%% TO DO: continue in remaining cases to verify src/dst_mtype if VerifyMethodHandles
     }
   }
   if (err != NULL) {
     throw_InternalError_for_bad_conversion(conversion, err, THREAD);
     return;
   }
 }
 void MethodHandles::init_AdapterMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
   oop  argument   = sun_dyn_AdapterMethodHandle::argument(mh());
   int  argslot    = sun_dyn_AdapterMethodHandle::vmargslot(mh());
   jint conversion = sun_dyn_AdapterMethodHandle::conversion(mh());
   jint conv_op    = adapter_conversion_op(conversion);
   // adjust the adapter code to the internal EntryKind enumeration:
   EntryKind ek_orig = adapter_entry_kind(conv_op);
   EntryKind ek_opt  = ek_orig;  // may be optimized
   // Finalize the vmtarget field (Java initialized it to null).
   if (!java_dyn_MethodHandle::is_instance(target())) {
     throw_InternalError_for_bad_conversion(conversion, "bad target", THREAD);
     return;
   }
   sun_dyn_AdapterMethodHandle::set_vmtarget(mh(), target());
   if (VerifyMethodHandles) {
     verify_AdapterMethodHandle(mh, argnum, CHECK);
   }
   int stack_move = adapter_conversion_stack_move(conversion);
   BasicType src  = adapter_conversion_src_type(conversion);
   BasicType dest = adapter_conversion_dest_type(conversion);
   int vminfo     = adapter_conversion_vminfo(conversion); // should be zero
   const char* err = NULL;
   // Now it's time to finish the case analysis and pick a MethodHandleEntry.
   switch (ek_orig) {
   case _adapter_retype_only:
   case _adapter_retype_raw:
   case _adapter_check_cast:
   case _adapter_dup_args:
   case _adapter_drop_args:
     // these work fine via general case code
     break;
   case _adapter_prim_to_prim:
     {
       // Non-subword cases are {int,float,long,double} -> {int,float,long,double}.
       // And, the {float,double} -> {int,long} cases must be handled by Java.
       switch (type2size[src] *4+ type2size[dest]) {
       case 1 *4+ 1:
         assert(src == T_INT || is_subword_type(src), "source is not float");
         // Subword-related cases are int -> {boolean,byte,char,short}.
         ek_opt = _adapter_opt_i2i;
         vminfo = adapter_subword_vminfo(dest);
         break;
       case 2 *4+ 1:
         if (src == T_LONG && (dest == T_INT || is_subword_type(dest))) {
           ek_opt = _adapter_opt_l2i;
           vminfo = adapter_subword_vminfo(dest);
         } else if (src == T_DOUBLE && dest == T_FLOAT) {
           ek_opt = _adapter_opt_d2f;
         } else {
           assert(false, "");
         }
         break;
       case 1 *4+ 2:
         if (src == T_INT && dest == T_LONG) {
           ek_opt = _adapter_opt_i2l;
         } else if (src == T_FLOAT && dest == T_DOUBLE) {
           ek_opt = _adapter_opt_f2d;
         } else {
           assert(false, "");
         }
         break;
       default:
         assert(false, "");
         break;
       }
     }
     break;
   case _adapter_ref_to_prim:
     {
       switch (type2size[dest]) {
       case 1:
         ek_opt = _adapter_opt_unboxi;
         vminfo = adapter_subword_vminfo(dest);
         break;
       case 2:
         ek_opt = _adapter_opt_unboxl;
         break;
       default:
         assert(false, "");
         break;
       }
     }
     break;
   case _adapter_prim_to_ref:
     goto throw_not_impl;        // allocates, hence could block
   case _adapter_swap_args:
   case _adapter_rot_args:
     {
       int swap_slots = type2size[src];
       int slot_limit = sun_dyn_AdapterMethodHandle::vmslots(mh());
       int src_slot   = argslot;
       int dest_slot  = vminfo;
       int rotate     = (ek_orig == _adapter_swap_args) ? 0 : (src_slot > dest_slot) ? 1 : -1;
       switch (swap_slots) {
       case 1:
         ek_opt = (!rotate    ? _adapter_opt_swap_1 :
                   rotate > 0 ? _adapter_opt_rot_1_up : _adapter_opt_rot_1_down);
         break;
       case 2:
         ek_opt = (!rotate    ? _adapter_opt_swap_2 :
                   rotate > 0 ? _adapter_opt_rot_2_up : _adapter_opt_rot_2_down);
         break;
       default:
         assert(false, "");
         break;
       }
     }
     break;
   case _adapter_collect_args:
     goto throw_not_impl;        // allocates, hence could block
   case _adapter_spread_args:
     {
       // vminfo will be the required length of the array
       int slots_pushed = stack_move / stack_move_unit();
       int array_size   = slots_pushed + 1;
       assert(array_size >= 0, "");
       vminfo = array_size;
       switch (array_size) {
       case 0:   ek_opt = _adapter_opt_spread_0;       break;
       case 1:   ek_opt = _adapter_opt_spread_1;       break;
       default:  ek_opt = _adapter_opt_spread_more;    break;
       }
       if ((vminfo & CONV_VMINFO_MASK) != vminfo)
         goto throw_not_impl;    // overflow
     }
     break;
   case _adapter_flyby:
   case _adapter_ricochet:
     goto throw_not_impl;        // runs Java code, hence could block
   default:
     // should have failed much earlier; must be a missing case here
     assert(false, "incomplete switch");
     // and fall through:
   throw_not_impl:
     // FIXME: these adapters are NYI
     err = "adapter not yet implemented in the JVM";
     break;
   }
   if (err != NULL) {
     throw_InternalError_for_bad_conversion(conversion, err, THREAD);
     return;
   }
   // Rebuild the conversion value; maybe parts of it were changed.
   jint new_conversion = adapter_conversion(conv_op, src, dest, stack_move, vminfo);
   // Finalize the conversion field.  (Note that it is final to Java code.)
   sun_dyn_AdapterMethodHandle::set_conversion(mh(), new_conversion);
   // Done!
   java_dyn_MethodHandle::set_vmentry(mh(), entry(ek_opt));
   // There should be enough memory barriers on exit from native methods
   // to ensure that the MH is fully initialized to all threads before
   // Java code can publish it in global data structures.
 }
 //
 // Here are the native methods on sun.dyn.MethodHandleImpl.
 // They are the private interface between this JVM and the HotSpot-specific
 // Java code that implements JSR 292 method handles.
 //
 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way
 // that intrinsic (non-JNI) native methods are defined in HotSpot.
 //
 // direct method handles for invokestatic or invokespecial
 // void init(DirectMethodHandle self, MemberName ref, boolean doDispatch, Class<?> caller);
 JVM_ENTRY(void, MHI_init_DMH(JNIEnv *env, jobject igcls, jobject mh_jh,
                              jobject target_jh, jboolean do_dispatch, jobject caller_jh)) {
   ResourceMark rm;              // for error messages
   // This is the guy we are initializing:
   if (mh_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
   // Early returns out of this method leave the DMH in an unfinished state.
   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
   // which method are we really talking about?
   if (target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   oop target_oop = JNIHandles::resolve_non_null(target_jh);
   if (sun_dyn_MemberName::is_instance(target_oop) &&
       sun_dyn_MemberName::vmindex(target_oop) == VM_INDEX_UNINITIALIZED) {
     Handle mname(THREAD, target_oop);
     MethodHandles::resolve_MemberName(mname, CHECK);
     target_oop = mname(); // in case of GC
   }
   int decode_flags = 0; klassOop receiver_limit = NULL;
   methodHandle m(THREAD,
                  MethodHandles::decode_method(target_oop,
                                               receiver_limit, decode_flags));
   if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "no such method"); }
   // The trusted Java code that calls this method should already have performed
   // access checks on behalf of the given caller.  But, we can verify this.
   if (VerifyMethodHandles && caller_jh != NULL) {
     KlassHandle caller(THREAD, java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(caller_jh)));
     // If this were a bytecode, the first access check would be against
     // the "reference class" mentioned in the CONSTANT_Methodref.
     // For that class, we use the defining class of m,
     // or a more specific receiver limit if available.
     klassOop reference_klass = m->method_holder();  // OK approximation
     if (receiver_limit != NULL && receiver_limit != reference_klass) {
       if (!Klass::cast(receiver_limit)->is_subtype_of(reference_klass))
         THROW_MSG(vmSymbols::java_lang_InternalError(), "receiver limit out of bounds");  // Java code bug
       reference_klass = receiver_limit;
     }
     // Emulate LinkResolver::check_klass_accessability.
     if (!Reflection::verify_class_access(caller->as_klassOop(),
                                          reference_klass,
                                          true)) {
       THROW_MSG(vmSymbols::java_lang_InternalError(), Klass::cast(m->method_holder())->external_name());
     }
     // If there were a bytecode, the next step would be to lookup the method
     // in the reference class, then then check the method's access bits.
     // Emulate LinkResolver::check_method_accessability.
     klassOop resolved_klass = m->method_holder();
     if (!Reflection::verify_field_access(caller->as_klassOop(),
                                          resolved_klass, reference_klass,
                                          m->access_flags(),
                                          true)) {
       // %%% following cutout belongs in Reflection::verify_field_access?
       bool same_pm = Reflection::is_same_package_member(caller->as_klassOop(),
                                                         reference_klass, THREAD);
       if (!same_pm) {
         THROW_MSG(vmSymbols::java_lang_InternalError(), m->name_and_sig_as_C_string());
       }
     }
   }
   MethodHandles::init_DirectMethodHandle(mh, m, (do_dispatch != JNI_FALSE), CHECK);
 }
 JVM_END
 // bound method handles
 JVM_ENTRY(void, MHI_init_BMH(JNIEnv *env, jobject igcls, jobject mh_jh,
                              jobject target_jh, int argnum)) {
   ResourceMark rm;              // for error messages
   // This is the guy we are initializing:
   if (mh_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
   // Early returns out of this method leave the BMH in an unfinished state.
   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
   if (target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
   if (!java_dyn_MethodHandle::is_instance(target())) {
     // Target object is a reflective method.  (%%% Do we need this alternate path?)
     Untested("init_BMH of non-MH");
     if (argnum != 0) { THROW(vmSymbols::java_lang_InternalError()); }
     int decode_flags = 0; klassOop receiver_limit_oop = NULL;
     methodHandle m(THREAD,
                    MethodHandles::decode_method(target(),
                                                 receiver_limit_oop,
                                                 decode_flags));
     KlassHandle receiver_limit(THREAD, receiver_limit_oop);
     MethodHandles::init_BoundMethodHandle_with_receiver(mh, m,
                                                        receiver_limit,
                                                        decode_flags,
                                                        CHECK);
     return;
   }
   // Build a BMH on top of a DMH or another BMH:
   MethodHandles::init_BoundMethodHandle(mh, target, argnum, CHECK);
 }
 JVM_END
 // adapter method handles
 JVM_ENTRY(void, MHI_init_AMH(JNIEnv *env, jobject igcls, jobject mh_jh,
                              jobject target_jh, int argnum)) {
   // This is the guy we are initializing:
   if (mh_jh == NULL || target_jh == NULL) {
     THROW(vmSymbols::java_lang_InternalError());
   }
   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
   // Early returns out of this method leave the AMH in an unfinished state.
   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
   MethodHandles::init_AdapterMethodHandle(mh, target, argnum, CHECK);
 }
 JVM_END
 // method type forms
 JVM_ENTRY(void, MHI_init_MT(JNIEnv *env, jobject igcls, jobject erased_jh)) {
   if (erased_jh == NULL)  return;
   if (TraceMethodHandles) {
     tty->print("creating MethodType form ");
     if (WizardMode || Verbose) {   // Warning: this calls Java code on the MH!
       // call Object.toString()
       symbolOop name = vmSymbols::toString_name(), sig = vmSymbols::void_string_signature();
       JavaCallArguments args(Handle(THREAD, JNIHandles::resolve_non_null(erased_jh)));
       JavaValue result(T_OBJECT);
       JavaCalls::call_virtual(&result, SystemDictionary::object_klass(), name, sig,
                               &args, CHECK);
       Handle str(THREAD, (oop)result.get_jobject());
       java_lang_String::print(str, tty);
     }
     tty->cr();
   }
 }
 JVM_END
 // debugging and reflection
 JVM_ENTRY(jobject, MHI_getTarget(JNIEnv *env, jobject igcls, jobject mh_jh, jint format)) {
   Handle mh(THREAD, JNIHandles::resolve(mh_jh));
   if (!java_dyn_MethodHandle::is_instance(mh())) {
     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
   }
   oop target = MethodHandles::encode_target(mh, format, CHECK_NULL);
   return JNIHandles::make_local(THREAD, target);
 }
 JVM_END
 JVM_ENTRY(jint, MHI_getConstant(JNIEnv *env, jobject igcls, jint which)) {
   switch (which) {
   case MethodHandles::GC_JVM_PUSH_LIMIT:
     guarantee(MethodHandlePushLimit >= 2 && MethodHandlePushLimit <= 0xFF,
               "MethodHandlePushLimit parameter must be in valid range");
     return MethodHandlePushLimit;
   case MethodHandles::GC_JVM_STACK_MOVE_UNIT:
     // return number of words per slot, signed according to stack direction
     return MethodHandles::stack_move_unit();
   }
   return 0;
 }
 JVM_END
 #ifndef PRODUCT
 #define EACH_NAMED_CON(template) \
     template(MethodHandles,GC_JVM_PUSH_LIMIT) \
     template(MethodHandles,GC_JVM_STACK_MOVE_UNIT) \
     template(MethodHandles,ETF_HANDLE_OR_METHOD_NAME) \
     template(MethodHandles,ETF_DIRECT_HANDLE) \
     template(MethodHandles,ETF_METHOD_NAME) \
     template(MethodHandles,ETF_REFLECT_METHOD) \
     template(sun_dyn_MemberName,MN_IS_METHOD) \
     template(sun_dyn_MemberName,MN_IS_CONSTRUCTOR) \
     template(sun_dyn_MemberName,MN_IS_FIELD) \
     template(sun_dyn_MemberName,MN_IS_TYPE) \
     template(sun_dyn_MemberName,MN_SEARCH_SUPERCLASSES) \
     template(sun_dyn_MemberName,MN_SEARCH_INTERFACES) \
     template(sun_dyn_MemberName,VM_INDEX_UNINITIALIZED) \
     template(sun_dyn_AdapterMethodHandle,OP_RETYPE_ONLY) \
     template(sun_dyn_AdapterMethodHandle,OP_RETYPE_RAW) \
     template(sun_dyn_AdapterMethodHandle,OP_CHECK_CAST) \
     template(sun_dyn_AdapterMethodHandle,OP_PRIM_TO_PRIM) \
     template(sun_dyn_AdapterMethodHandle,OP_REF_TO_PRIM) \
     template(sun_dyn_AdapterMethodHandle,OP_PRIM_TO_REF) \
     template(sun_dyn_AdapterMethodHandle,OP_SWAP_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_ROT_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_DUP_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_DROP_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_COLLECT_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_SPREAD_ARGS) \
     template(sun_dyn_AdapterMethodHandle,OP_FLYBY) \
     template(sun_dyn_AdapterMethodHandle,OP_RICOCHET) \
     template(sun_dyn_AdapterMethodHandle,CONV_OP_LIMIT) \
     template(sun_dyn_AdapterMethodHandle,CONV_OP_MASK) \
     template(sun_dyn_AdapterMethodHandle,CONV_VMINFO_MASK) \
     template(sun_dyn_AdapterMethodHandle,CONV_VMINFO_SHIFT) \
     template(sun_dyn_AdapterMethodHandle,CONV_OP_SHIFT) \
     template(sun_dyn_AdapterMethodHandle,CONV_DEST_TYPE_SHIFT) \
     template(sun_dyn_AdapterMethodHandle,CONV_SRC_TYPE_SHIFT) \
     template(sun_dyn_AdapterMethodHandle,CONV_STACK_MOVE_SHIFT) \
     template(sun_dyn_AdapterMethodHandle,CONV_STACK_MOVE_MASK) \
     /*end*/
 #define ONE_PLUS(scope,value) 1+
 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS) 0;
 #define VALUE_COMMA(scope,value) scope::value,
 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA) 0 };
 #define STRING_NULL(scope,value) #value "\0"
 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL) };
 #undef ONE_PLUS
 #undef VALUE_COMMA
 #undef STRING_NULL
 #undef EACH_NAMED_CON
 #endif
 JVM_ENTRY(jint, MHI_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
 #ifndef PRODUCT
   if (which >= 0 && which < con_value_count) {
     int con = con_values[which];
     objArrayOop box = (objArrayOop) JNIHandles::resolve(box_jh);
     if (box != NULL && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
       const char* str = &con_names[0];
       for (int i = 0; i < which; i++)
         str += strlen(str) + 1;   // skip name and null
       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);
       box->obj_at_put(0, name);
     }
     return con;
   }
 #endif
   return 0;
 }
 JVM_END
 // void init(MemberName self, AccessibleObject ref)
 JVM_ENTRY(void, MHI_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
   if (mname_jh == NULL || target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
   oop target_oop = JNIHandles::resolve_non_null(target_jh);
   MethodHandles::init_MemberName(mname(), target_oop);
 }
 JVM_END
 // void expand(MemberName self)
 JVM_ENTRY(void, MHI_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
   if (mname_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
   MethodHandles::expand_MemberName(mname, 0, CHECK);
 }
 JVM_END
 // void resolve(MemberName self, Class<?> caller)
 JVM_ENTRY(void, MHI_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
   if (mname_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
   // %%% take caller into account!
   MethodHandles::resolve_MemberName(mname, CHECK);
 }
 JVM_END
 //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
 //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
 JVM_ENTRY(jint, MHI_getMembers(JNIEnv *env, jobject igcls,
                                jclass clazz_jh, jstring name_jh, jstring sig_jh,
                                int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
   if (clazz_jh == NULL || results_jh == NULL)  return -1;
   klassOop k_oop = java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(clazz_jh));
   objArrayOop results = (objArrayOop) JNIHandles::resolve(results_jh);
   if (results == NULL || !results->is_objArray())       return -1;
   symbolOop name = NULL, sig = NULL;
   if (name_jh != NULL) {
     name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
     if (name == NULL)  return 0; // a match is not possible
   }
   if (sig_jh != NULL) {
     sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
     if (sig == NULL)  return 0; // a match is not possible
   }
   klassOop caller = NULL;
   if (caller_jh != NULL) {
     oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
     if (!java_lang_Class::is_instance(caller_oop))  return -1;
     caller = java_lang_Class::as_klassOop(caller_oop);
   }
   if (name != NULL && sig != NULL && results != NULL) {
     // try a direct resolve
     // %%% TO DO
   }
   int res = MethodHandles::find_MemberNames(k_oop, name, sig, mflags,
                                             caller, skip, results);
   // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
   return res;
 }
 JVM_END
 JVM_ENTRY(void, MH_linkCallSite(JNIEnv *env, jobject igcls, jobject site_jh, jobject target_jh)) {
   // No special action required, yet.
   oop site_oop = JNIHandles::resolve(site_jh);
   if (site_oop == NULL || site_oop->klass() != SystemDictionary::CallSiteImpl_klass())
     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "call site");
   sun_dyn_CallSiteImpl::set_target(site_oop, JNIHandles::resolve(target_jh));
 }
 JVM_END
 /// JVM_RegisterMethodHandleMethods
 #define ADR "J"
 #define LANG "Ljava/lang/"
 #define JDYN "Ljava/dyn/"
 #define IDYN "Lsun/dyn/"
 #define OBJ   LANG"Object;"
 #define CLS   LANG"Class;"
 #define STRG  LANG"String;"
 #define MT    JDYN"MethodType;"
 #define MH    JDYN"MethodHandle;"
 #define MHI   IDYN"MethodHandleImpl;"
 #define MEM   IDYN"MemberName;"
 #define AMH   IDYN"AdapterMethodHandle;"
 #define BMH   IDYN"BoundMethodHandle;"
 #define DMH   IDYN"DirectMethodHandle;"
 #define CSTI  IDYN"CallSiteImpl;"
 #define CC (char*)  /*cast a literal from (const char*)*/
 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
 // These are the native methods on sun.dyn.MethodHandleNatives.
 static JNINativeMethod methods[] = {
   // void init(MemberName self, AccessibleObject ref)
   {CC"init",                    CC"("AMH""MH"I)V",              FN_PTR(MHI_init_AMH)},
   {CC"init",                    CC"("BMH""OBJ"I)V",             FN_PTR(MHI_init_BMH)},
   {CC"init",                    CC"("DMH""OBJ"Z"CLS")V",        FN_PTR(MHI_init_DMH)},
   {CC"init",                    CC"("MT")V",                    FN_PTR(MHI_init_MT)},
   {CC"init",                    CC"("MEM""OBJ")V",              FN_PTR(MHI_init_Mem)},
   {CC"expand",                  CC"("MEM")V",                   FN_PTR(MHI_expand_Mem)},
   {CC"resolve",                 CC"("MEM""CLS")V",              FN_PTR(MHI_resolve_Mem)},
   {CC"getTarget",               CC"("MH"I)"OBJ,                 FN_PTR(MHI_getTarget)},
   {CC"getConstant",             CC"(I)I",                       FN_PTR(MHI_getConstant)},
   //  static native int getNamedCon(int which, Object[] name)
   {CC"getNamedCon",             CC"(I["OBJ")I",                 FN_PTR(MHI_getNamedCon)},
   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
   {CC"getMembers",              CC"("CLS""STRG""STRG"I"CLS"I["MEM")I",  FN_PTR(MHI_getMembers)}
 };
 // More entry points specifically for EnableInvokeDynamic.
 static JNINativeMethod methods2[] = {
   {CC"linkCallSite",            CC"("CSTI MH")V",               FN_PTR(MH_linkCallSite)}
 };
 // This one function is exported, used by NativeLookup.
 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
   assert(MethodHandles::spot_check_entry_names(), "entry enum is OK");
   // note: this explicit warning-producing stuff will be replaced by auto-detection of the JSR 292 classes
   if (!EnableMethodHandles) {
     warning("JSR 292 method handles are disabled in this JVM.  Use -XX:+UnlockExperimentalVMOptions -XX:+EnableMethodHandles to enable.");
     return;  // bind nothing
   }
   bool enable_MH = true;
   {
     ThreadToNativeFromVM ttnfv(thread);
     int status = env->RegisterNatives(MHN_class, methods, sizeof(methods)/sizeof(JNINativeMethod));
     if (env->ExceptionOccurred()) {
       MethodHandles::set_enabled(false);
       warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
       enable_MH = false;
       env->ExceptionClear();
     }
   }
   if (enable_MH) {
     KlassHandle MHI_klass = SystemDictionaryHandles::MethodHandleImpl_klass();
     if (MHI_klass.not_null()) {
       symbolHandle raiseException_name = oopFactory::new_symbol_handle("raiseException", CHECK);
       symbolHandle raiseException_sig  = oopFactory::new_symbol_handle("(ILjava/lang/Object;Ljava/lang/Object;)V", CHECK);
       methodOop raiseException_method  = instanceKlass::cast(MHI_klass->as_klassOop())
                     ->find_method(raiseException_name(), raiseException_sig());
       if (raiseException_method != NULL && raiseException_method->is_static()) {
         MethodHandles::set_raise_exception_method(raiseException_method);
       } else {
         warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
         enable_MH = false;
       }
     }
   }
   if (enable_MH) {
     MethodHandles::set_enabled(true);
   }
   if (!EnableInvokeDynamic) {
     warning("JSR 292 invokedynamic is disabled in this JVM.  Use -XX:+UnlockExperimentalVMOptions -XX:+EnableInvokeDynamic to enable.");
     return;  // bind nothing
   }
   {
     ThreadToNativeFromVM ttnfv(thread);
     int status = env->RegisterNatives(MHN_class, methods2, sizeof(methods2)/sizeof(JNINativeMethod));
     if (env->ExceptionOccurred()) {
       MethodHandles::set_enabled(false);
       warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
       env->ExceptionClear();
     } else {
       MethodHandles::set_enabled(true);
     }
   }
 }
 JVM_END

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/prims/methodHandles.cpp@987e948ebbc8 (annotated)

src/share/vm/prims/methodHandles.cpp