1 /*
   2  * Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaClasses.inline.hpp"
  27 #include "classfile/stringTable.hpp"
  28 #include "classfile/symbolTable.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "code/dependencyContext.hpp"
  31 #include "compiler/compileBroker.hpp"
  32 #include "interpreter/interpreter.hpp"
  33 #include "interpreter/oopMapCache.hpp"
  34 #include "interpreter/linkResolver.hpp"
  35 #include "memory/allocation.inline.hpp"
  36 #include "memory/oopFactory.hpp"
  37 #include "memory/resourceArea.hpp"
  38 #include "memory/universe.hpp"
  39 #include "oops/objArrayKlass.hpp"
  40 #include "oops/objArrayOop.inline.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "oops/typeArrayOop.inline.hpp"
  43 #include "prims/methodHandles.hpp"
  44 #include "runtime/deoptimization.hpp"
  45 #include "runtime/fieldDescriptor.inline.hpp"
  46 #include "runtime/handles.inline.hpp"
  47 #include "runtime/interfaceSupport.inline.hpp"
  48 #include "runtime/javaCalls.hpp"
  49 #include "runtime/jniHandles.inline.hpp"
  50 #include "runtime/timerTrace.hpp"
  51 #include "runtime/reflection.hpp"
  52 #include "runtime/safepointVerifiers.hpp"
  53 #include "runtime/signature.hpp"
  54 #include "runtime/stubRoutines.hpp"
  55 #include "utilities/exceptions.hpp"
  56 
  57 
  58 /*
  59  * JSR 292 reference implementation: method handles
  60  * The JDK 7 reference implementation represented method handle
  61  * combinations as chains.  Each link in the chain had a "vmentry"
  62  * field which pointed at a bit of assembly code which performed
  63  * one transformation before dispatching to the next link in the chain.
  64  *
  65  * The current reference implementation pushes almost all code generation
  66  * responsibility to (trusted) Java code.  A method handle contains a
  67  * pointer to its "LambdaForm", which embodies all details of the method
  68  * handle's behavior.  The LambdaForm is a normal Java object, managed
  69  * by a runtime coded in Java.
  70  */
  71 
  72 bool MethodHandles::_enabled = false; // set true after successful native linkage
  73 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;
  74 
  75 /**
  76  * Generates method handle adapters. Returns 'false' if memory allocation
  77  * failed and true otherwise.
  78  */
  79 void MethodHandles::generate_adapters() {
  80   assert(SystemDictionary::MethodHandle_klass() != NULL, "should be present");
  81   assert(_adapter_code == NULL, "generate only once");
  82 
  83   ResourceMark rm;
  84   TraceTime timer("MethodHandles adapters generation", TRACETIME_LOG(Info, startuptime));
  85   _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);
  86   CodeBuffer code(_adapter_code);
  87   MethodHandlesAdapterGenerator g(&code);
  88   g.generate();
  89   code.log_section_sizes("MethodHandlesAdapterBlob");
  90 }
  91 
  92 //------------------------------------------------------------------------------
  93 // MethodHandlesAdapterGenerator::generate
  94 //
  95 void MethodHandlesAdapterGenerator::generate() {
  96   // Generate generic method handle adapters.
  97   // Generate interpreter entries
  98   for (Interpreter::MethodKind mk = Interpreter::method_handle_invoke_FIRST;
  99        mk <= Interpreter::method_handle_invoke_LAST;
 100        mk = Interpreter::MethodKind(1 + (int)mk)) {
 101     vmIntrinsics::ID iid = Interpreter::method_handle_intrinsic(mk);
 102     StubCodeMark mark(this, "MethodHandle::interpreter_entry", vmIntrinsics::name_at(iid));
 103     address entry = MethodHandles::generate_method_handle_interpreter_entry(_masm, iid);
 104     if (entry != NULL) {
 105       Interpreter::set_entry_for_kind(mk, entry);
 106     }
 107     // If the entry is not set, it will throw AbstractMethodError.
 108   }
 109 }
 110 
 111 void MethodHandles::set_enabled(bool z) {
 112   if (_enabled != z) {
 113     guarantee(z, "can only enable once");
 114     _enabled = z;
 115   }
 116 }
 117 
 118 // MemberName support
 119 
 120 // import java_lang_invoke_MemberName.*
 121 enum {
 122   IS_METHOD            = java_lang_invoke_MemberName::MN_IS_METHOD,
 123   IS_CONSTRUCTOR       = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,
 124   IS_FIELD             = java_lang_invoke_MemberName::MN_IS_FIELD,
 125   IS_TYPE              = java_lang_invoke_MemberName::MN_IS_TYPE,
 126   CALLER_SENSITIVE     = java_lang_invoke_MemberName::MN_CALLER_SENSITIVE,
 127   REFERENCE_KIND_SHIFT = java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT,
 128   REFERENCE_KIND_MASK  = java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,
 129   SEARCH_SUPERCLASSES  = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,
 130   SEARCH_INTERFACES    = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,
 131   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE
 132 };
 133 
 134 int MethodHandles::ref_kind_to_flags(int ref_kind) {
 135   assert(ref_kind_is_valid(ref_kind), "%d", ref_kind);
 136   int flags = (ref_kind << REFERENCE_KIND_SHIFT);
 137   if (ref_kind_is_field(ref_kind)) {
 138     flags |= IS_FIELD;
 139   } else if (ref_kind_is_method(ref_kind)) {
 140     flags |= IS_METHOD;
 141   } else if (ref_kind == JVM_REF_newInvokeSpecial) {
 142     flags |= IS_CONSTRUCTOR;
 143   }
 144   return flags;
 145 }
 146 
 147 Handle MethodHandles::resolve_MemberName_type(Handle mname, Klass* caller, TRAPS) {
 148   Handle empty;
 149   Handle type(THREAD, java_lang_invoke_MemberName::type(mname()));
 150   if (!java_lang_String::is_instance_inlined(type())) {
 151     return type; // already resolved
 152   }
 153   Symbol* signature = java_lang_String::as_symbol_or_null(type());
 154   if (signature == NULL) {
 155     return empty;  // no such signature exists in the VM
 156   }
 157   Handle resolved;
 158   int flags = java_lang_invoke_MemberName::flags(mname());
 159   switch (flags & ALL_KINDS) {
 160     case IS_METHOD:
 161     case IS_CONSTRUCTOR:
 162       resolved = SystemDictionary::find_method_handle_type(signature, caller, CHECK_(empty));
 163       break;
 164     case IS_FIELD:
 165       resolved = SystemDictionary::find_field_handle_type(signature, caller, CHECK_(empty));
 166       break;
 167     default:
 168       THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
 169   }
 170   if (resolved.is_null()) {
 171     THROW_MSG_(vmSymbols::java_lang_InternalError(), "bad MemberName type", empty);
 172   }
 173   return resolved;
 174 }
 175 
 176 oop MethodHandles::init_MemberName(Handle mname, Handle target, TRAPS) {
 177   // This method is used from java.lang.invoke.MemberName constructors.
 178   // It fills in the new MemberName from a java.lang.reflect.Member.
 179   Thread* thread = Thread::current();
 180   oop target_oop = target();
 181   Klass* target_klass = target_oop->klass();
 182   if (target_klass == SystemDictionary::reflect_Field_klass()) {
 183     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
 184     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()
 185     Klass* k = java_lang_Class::as_Klass(clazz);
 186     if (k != NULL && k->is_instance_klass()) {
 187       fieldDescriptor fd(InstanceKlass::cast(k), slot);
 188       oop mname2 = init_field_MemberName(mname, fd);
 189       if (mname2 != NULL) {
 190         // Since we have the reified name and type handy, add them to the result.
 191         if (java_lang_invoke_MemberName::name(mname2) == NULL)
 192           java_lang_invoke_MemberName::set_name(mname2, java_lang_reflect_Field::name(target_oop));
 193         if (java_lang_invoke_MemberName::type(mname2) == NULL)
 194           java_lang_invoke_MemberName::set_type(mname2, java_lang_reflect_Field::type(target_oop));
 195       }
 196       return mname2;
 197     }
 198   } else if (target_klass == SystemDictionary::reflect_Method_klass()) {
 199     oop clazz  = java_lang_reflect_Method::clazz(target_oop);
 200     int slot   = java_lang_reflect_Method::slot(target_oop);
 201     Klass* k = java_lang_Class::as_Klass(clazz);
 202     if (k != NULL && k->is_instance_klass()) {
 203       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
 204       if (m == NULL || is_signature_polymorphic(m->intrinsic_id()))
 205         return NULL;            // do not resolve unless there is a concrete signature
 206       CallInfo info(m, k, CHECK_NULL);
 207       return init_method_MemberName(mname, info);
 208     }
 209   } else if (target_klass == SystemDictionary::reflect_Constructor_klass()) {
 210     oop clazz  = java_lang_reflect_Constructor::clazz(target_oop);
 211     int slot   = java_lang_reflect_Constructor::slot(target_oop);
 212     Klass* k = java_lang_Class::as_Klass(clazz);
 213     if (k != NULL && k->is_instance_klass()) {
 214       Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
 215       if (m == NULL)  return NULL;
 216       CallInfo info(m, k, CHECK_NULL);
 217       return init_method_MemberName(mname, info);
 218     }
 219   }
 220   return NULL;
 221 }
 222 
 223 oop MethodHandles::init_method_MemberName(Handle mname, CallInfo& info) {
 224   assert(info.resolved_appendix().is_null(), "only normal methods here");
 225   methodHandle m(Thread::current(), info.resolved_method());
 226   assert(m.not_null(), "null method handle");
 227   InstanceKlass* m_klass = m->method_holder();
 228   assert(m_klass != NULL, "null holder for method handle");
 229   int flags = (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS );
 230   int vmindex = Method::invalid_vtable_index;
 231 
 232   switch (info.call_kind()) {
 233   case CallInfo::itable_call:
 234     vmindex = info.itable_index();
 235     // More importantly, the itable index only works with the method holder.
 236     assert(m_klass->verify_itable_index(vmindex), "");
 237     flags |= IS_METHOD | (JVM_REF_invokeInterface << REFERENCE_KIND_SHIFT);
 238     if (TraceInvokeDynamic) {
 239       ttyLocker ttyl;
 240       ResourceMark rm;
 241       tty->print_cr("memberName: invokeinterface method_holder::method: %s, itableindex: %d, access_flags:",
 242             Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),
 243             vmindex);
 244        m->access_flags().print_on(tty);
 245        if (!m->is_abstract()) {
 246          if (!m->is_private()) {
 247            tty->print("default");
 248          }
 249          else {
 250            tty->print("private-intf");
 251          }
 252        }
 253        tty->cr();
 254     }
 255     break;
 256 
 257   case CallInfo::vtable_call:
 258     vmindex = info.vtable_index();
 259     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
 260     assert(info.resolved_klass()->is_subtype_of(m_klass), "virtual call must be type-safe");
 261     if (m_klass->is_interface()) {
 262       // This is a vtable call to an interface method (abstract "miranda method" or default method).
 263       // The vtable index is meaningless without a class (not interface) receiver type, so get one.
 264       // (LinkResolver should help us figure this out.)
 265       assert(info.resolved_klass()->is_instance_klass(), "subtype of interface must be an instance klass");
 266       InstanceKlass* m_klass_non_interface = InstanceKlass::cast(info.resolved_klass());
 267       if (m_klass_non_interface->is_interface()) {
 268         m_klass_non_interface = SystemDictionary::Object_klass();
 269 #ifdef ASSERT
 270         { ResourceMark rm;
 271           Method* m2 = m_klass_non_interface->vtable().method_at(vmindex);
 272           assert(m->name() == m2->name() && m->signature() == m2->signature(),
 273                  "at %d, %s != %s", vmindex,
 274                  m->name_and_sig_as_C_string(), m2->name_and_sig_as_C_string());
 275         }
 276 #endif //ASSERT
 277       }
 278       if (!m->is_public()) {
 279         assert(m->is_public(), "virtual call must be to public interface method");
 280         return NULL;  // elicit an error later in product build
 281       }
 282       assert(info.resolved_klass()->is_subtype_of(m_klass_non_interface), "virtual call must be type-safe");
 283       m_klass = m_klass_non_interface;
 284     }
 285     if (TraceInvokeDynamic) {
 286       ttyLocker ttyl;
 287       ResourceMark rm;
 288       tty->print_cr("memberName: invokevirtual method_holder::method: %s, receiver: %s, vtableindex: %d, access_flags:",
 289             Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),
 290             m_klass->internal_name(), vmindex);
 291        m->access_flags().print_on(tty);
 292        if (m->is_default_method()) {
 293          tty->print("default");
 294        }
 295        tty->cr();
 296     }
 297     break;
 298 
 299   case CallInfo::direct_call:
 300     vmindex = Method::nonvirtual_vtable_index;
 301     if (m->is_static()) {
 302       flags |= IS_METHOD      | (JVM_REF_invokeStatic  << REFERENCE_KIND_SHIFT);
 303     } else if (m->is_initializer()) {
 304       flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
 305     } else {
 306       // "special" reflects that this is a direct call, not that it
 307       // necessarily originates from an invokespecial. We can also do
 308       // direct calls for private and/or final non-static methods.
 309       flags |= IS_METHOD      | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
 310     }
 311     break;
 312 
 313   default:  assert(false, "bad CallInfo");  return NULL;
 314   }
 315 
 316   // @CallerSensitive annotation detected
 317   if (m->caller_sensitive()) {
 318     flags |= CALLER_SENSITIVE;
 319   }
 320 
 321   Handle resolved_method = info.resolved_method_name();
 322   assert(java_lang_invoke_ResolvedMethodName::vmtarget(resolved_method()) == m() || m->is_old(),
 323          "Should not change after link resolution");
 324 
 325   oop mname_oop = mname();
 326   java_lang_invoke_MemberName::set_flags  (mname_oop, flags);
 327   java_lang_invoke_MemberName::set_method (mname_oop, resolved_method());
 328   java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);   // vtable/itable index
 329   java_lang_invoke_MemberName::set_clazz  (mname_oop, m_klass->java_mirror());
 330   // Note:  name and type can be lazily computed by resolve_MemberName,
 331   // if Java code needs them as resolved String and MethodType objects.
 332   // If relevant, the vtable or itable value is stored as vmindex.
 333   // This is done eagerly, since it is readily available without
 334   // constructing any new objects.
 335   return mname();
 336 }
 337 
 338 oop MethodHandles::init_field_MemberName(Handle mname, fieldDescriptor& fd, bool is_setter) {
 339   int flags = (jushort)( fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS );
 340   flags |= IS_FIELD | ((fd.is_static() ? JVM_REF_getStatic : JVM_REF_getField) << REFERENCE_KIND_SHIFT);
 341   if (is_setter)  flags += ((JVM_REF_putField - JVM_REF_getField) << REFERENCE_KIND_SHIFT);
 342   int vmindex        = fd.offset();  // determines the field uniquely when combined with static bit
 343 
 344   oop mname_oop = mname();
 345   java_lang_invoke_MemberName::set_flags  (mname_oop, flags);
 346   java_lang_invoke_MemberName::set_method (mname_oop, NULL);
 347   java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);
 348   java_lang_invoke_MemberName::set_clazz  (mname_oop, fd.field_holder()->java_mirror());
 349 
 350   oop type = field_signature_type_or_null(fd.signature());
 351   oop name = field_name_or_null(fd.name());
 352   if (name != NULL)
 353     java_lang_invoke_MemberName::set_name(mname_oop,   name);
 354   if (type != NULL)
 355     java_lang_invoke_MemberName::set_type(mname_oop,   type);
 356   // Note:  name and type can be lazily computed by resolve_MemberName,
 357   // if Java code needs them as resolved String and Class objects.
 358   // Note that the incoming type oop might be pre-resolved (non-null).
 359   // The base clazz and field offset (vmindex) must be eagerly stored,
 360   // because they unambiguously identify the field.
 361   // Although the fieldDescriptor::_index would also identify the field,
 362   // we do not use it, because it is harder to decode.
 363   // TO DO: maybe intern mname_oop
 364   return mname();
 365 }
 366 
 367 // JVM 2.9 Special Methods:
 368 // A method is signature polymorphic if and only if all of the following conditions hold :
 369 // * It is declared in the java.lang.invoke.MethodHandle/VarHandle classes.
 370 // * It has a single formal parameter of type Object[].
 371 // * It has a return type of Object for a polymorphic return type, otherwise a fixed return type.
 372 // * It has the ACC_VARARGS and ACC_NATIVE flags set.
 373 bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
 374   if (klass == NULL)
 375     return false;
 376   // The following test will fail spuriously during bootstrap of MethodHandle itself:
 377   //    if (klass != SystemDictionary::MethodHandle_klass())
 378   // Test the name instead:
 379   if (klass->name() != vmSymbols::java_lang_invoke_MethodHandle() &&
 380       klass->name() != vmSymbols::java_lang_invoke_VarHandle()) {
 381     return false;
 382   }
 383 
 384   // Look up signature polymorphic method with polymorphic return type
 385   Symbol* poly_sig = vmSymbols::object_array_object_signature();
 386   InstanceKlass* iklass = InstanceKlass::cast(klass);
 387   Method* m = iklass->find_method(name, poly_sig);
 388   if (m != NULL) {
 389     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
 390     int flags = m->access_flags().as_int();
 391     if ((flags & required) == required) {
 392       return true;
 393     }
 394   }
 395 
 396   // Look up signature polymorphic method with non-polymorphic (non Object) return type
 397   int me;
 398   int ms = iklass->find_method_by_name(name, &me);
 399   if (ms == -1) return false;
 400   for (; ms < me; ms++) {
 401     Method* m = iklass->methods()->at(ms);
 402     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
 403     int flags = m->access_flags().as_int();
 404     if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {
 405       return true;
 406     }
 407   }
 408   return false;
 409 }
 410 
 411 
 412 Symbol* MethodHandles::signature_polymorphic_intrinsic_name(vmIntrinsics::ID iid) {
 413   assert(is_signature_polymorphic_intrinsic(iid), "%d %s", iid, vmIntrinsics::name_at(iid));
 414   switch (iid) {
 415   case vmIntrinsics::_invokeBasic:      return vmSymbols::invokeBasic_name();
 416   case vmIntrinsics::_linkToVirtual:    return vmSymbols::linkToVirtual_name();
 417   case vmIntrinsics::_linkToStatic:     return vmSymbols::linkToStatic_name();
 418   case vmIntrinsics::_linkToSpecial:    return vmSymbols::linkToSpecial_name();
 419   case vmIntrinsics::_linkToInterface:  return vmSymbols::linkToInterface_name();
 420   default:
 421     fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));
 422     return 0;
 423   }
 424 }
 425 
 426 Bytecodes::Code MethodHandles::signature_polymorphic_intrinsic_bytecode(vmIntrinsics::ID id) {
 427   switch(id) {
 428     case vmIntrinsics::_linkToVirtual:   return Bytecodes::_invokevirtual;
 429     case vmIntrinsics::_linkToInterface: return Bytecodes::_invokeinterface;
 430     case vmIntrinsics::_linkToStatic:    return Bytecodes::_invokestatic;
 431     case vmIntrinsics::_linkToSpecial:   return Bytecodes::_invokespecial;
 432     case vmIntrinsics::_invokeBasic:     return Bytecodes::_invokehandle;
 433     default:
 434       fatal("unexpected id: (%d) %s", (uint)id, vmIntrinsics::name_at(id));
 435       return Bytecodes::_illegal;
 436   }
 437 }
 438 
 439 int MethodHandles::signature_polymorphic_intrinsic_ref_kind(vmIntrinsics::ID iid) {
 440   switch (iid) {
 441   case vmIntrinsics::_invokeBasic:      return 0;
 442   case vmIntrinsics::_linkToVirtual:    return JVM_REF_invokeVirtual;
 443   case vmIntrinsics::_linkToStatic:     return JVM_REF_invokeStatic;
 444   case vmIntrinsics::_linkToSpecial:    return JVM_REF_invokeSpecial;
 445   case vmIntrinsics::_linkToInterface:  return JVM_REF_invokeInterface;
 446   default:
 447     fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));
 448     return 0;
 449   }
 450 }
 451 
 452 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Symbol* name) {
 453   vmSymbols::SID name_id = vmSymbols::find_sid(name);
 454   switch (name_id) {
 455   // The ID _invokeGeneric stands for all non-static signature-polymorphic methods, except built-ins.
 456   case vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name):           return vmIntrinsics::_invokeGeneric;
 457   // The only built-in non-static signature-polymorphic method is MethodHandle.invokeBasic:
 458   case vmSymbols::VM_SYMBOL_ENUM_NAME(invokeBasic_name):      return vmIntrinsics::_invokeBasic;
 459 
 460   // There is one static signature-polymorphic method for each JVM invocation mode.
 461   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToVirtual_name):    return vmIntrinsics::_linkToVirtual;
 462   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToStatic_name):     return vmIntrinsics::_linkToStatic;
 463   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToSpecial_name):    return vmIntrinsics::_linkToSpecial;
 464   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToInterface_name):  return vmIntrinsics::_linkToInterface;
 465   default:                                                    break;
 466   }
 467 
 468   // Cover the case of invokeExact and any future variants of invokeFoo.
 469   Klass* mh_klass = SystemDictionary::well_known_klass(
 470                               SystemDictionary::WK_KLASS_ENUM_NAME(MethodHandle_klass) );
 471   if (mh_klass != NULL && is_method_handle_invoke_name(mh_klass, name)) {
 472     return vmIntrinsics::_invokeGeneric;
 473   }
 474 
 475   // Cover the case of methods on VarHandle.
 476   Klass* vh_klass = SystemDictionary::well_known_klass(
 477                               SystemDictionary::WK_KLASS_ENUM_NAME(VarHandle_klass) );
 478   if (vh_klass != NULL && is_method_handle_invoke_name(vh_klass, name)) {
 479     return vmIntrinsics::_invokeGeneric;
 480   }
 481 
 482   // Note: The pseudo-intrinsic _compiledLambdaForm is never linked against.
 483   // Instead it is used to mark lambda forms bound to invokehandle or invokedynamic.
 484   return vmIntrinsics::_none;
 485 }
 486 
 487 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Klass* klass, Symbol* name) {
 488   if (klass != NULL &&
 489       (klass->name() == vmSymbols::java_lang_invoke_MethodHandle() ||
 490        klass->name() == vmSymbols::java_lang_invoke_VarHandle())) {
 491     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
 492     if (iid != vmIntrinsics::_none)
 493       return iid;
 494     if (is_method_handle_invoke_name(klass, name))
 495       return vmIntrinsics::_invokeGeneric;
 496   }
 497   return vmIntrinsics::_none;
 498 }
 499 
 500 // Returns true if method is signature polymorphic and public
 501 bool MethodHandles::is_signature_polymorphic_public_name(Klass* klass, Symbol* name) {
 502   if (is_signature_polymorphic_name(klass, name)) {
 503     InstanceKlass* iklass = InstanceKlass::cast(klass);
 504     int me;
 505     int ms = iklass->find_method_by_name(name, &me);
 506     assert(ms != -1, "");
 507     for (; ms < me; ms++) {
 508       Method* m = iklass->methods()->at(ms);
 509       int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS | JVM_ACC_PUBLIC;
 510       int flags = m->access_flags().as_int();
 511       if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {
 512         return true;
 513       }
 514     }
 515   }
 516   return false;
 517 }
 518 
 519 // convert the external string or reflective type to an internal signature
 520 Symbol* MethodHandles::lookup_signature(oop type_str, bool intern_if_not_found, TRAPS) {
 521   if (java_lang_invoke_MethodType::is_instance(type_str)) {
 522     return java_lang_invoke_MethodType::as_signature(type_str, intern_if_not_found);
 523   } else if (java_lang_Class::is_instance(type_str)) {
 524     return java_lang_Class::as_signature(type_str, false);
 525   } else if (java_lang_String::is_instance_inlined(type_str)) {
 526     if (intern_if_not_found) {
 527       return java_lang_String::as_symbol(type_str);
 528     } else {
 529       return java_lang_String::as_symbol_or_null(type_str);
 530     }
 531   } else {
 532     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);
 533   }
 534 }
 535 
 536 static const char OBJ_SIG[] = "Ljava/lang/Object;";
 537 enum { OBJ_SIG_LEN = 18 };
 538 
 539 bool MethodHandles::is_basic_type_signature(Symbol* sig) {
 540   assert(vmSymbols::object_signature()->utf8_length() == (int)OBJ_SIG_LEN, "");
 541   assert(vmSymbols::object_signature()->equals(OBJ_SIG), "");
 542   const int len = sig->utf8_length();
 543   for (int i = 0; i < len; i++) {
 544     switch (sig->char_at(i)) {
 545     case JVM_SIGNATURE_CLASS:
 546       // only java/lang/Object is valid here
 547       if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)
 548         return false;
 549       i += OBJ_SIG_LEN-1;  //-1 because of i++ in loop
 550       continue;
 551     case JVM_SIGNATURE_FUNC:
 552     case JVM_SIGNATURE_ENDFUNC:
 553     case JVM_SIGNATURE_VOID:
 554     case JVM_SIGNATURE_INT:
 555     case JVM_SIGNATURE_LONG:
 556     case JVM_SIGNATURE_FLOAT:
 557     case JVM_SIGNATURE_DOUBLE:
 558       continue;
 559     default:
 560       // subword types (T_BYTE etc.), arrays
 561       return false;
 562     }
 563   }
 564   return true;
 565 }
 566 
 567 Symbol* MethodHandles::lookup_basic_type_signature(Symbol* sig, bool keep_last_arg, TRAPS) {
 568   Symbol* bsig = NULL;
 569   if (sig == NULL) {
 570     return sig;
 571   } else if (is_basic_type_signature(sig)) {
 572     sig->increment_refcount();
 573     return sig;  // that was easy
 574   } else if (sig->char_at(0) != JVM_SIGNATURE_FUNC) {
 575     BasicType bt = char2type(sig->char_at(0));
 576     if (is_subword_type(bt)) {
 577       bsig = vmSymbols::int_signature();
 578     } else {
 579       assert(is_reference_type(bt), "is_basic_type_signature was false");
 580       bsig = vmSymbols::object_signature();
 581     }
 582   } else {
 583     ResourceMark rm;
 584     stringStream buffer(128);
 585     buffer.put(JVM_SIGNATURE_FUNC);
 586     int arg_pos = 0, keep_arg_pos = -1;
 587     if (keep_last_arg)
 588       keep_arg_pos = ArgumentCount(sig).size() - 1;
 589     for (SignatureStream ss(sig); !ss.is_done(); ss.next()) {
 590       BasicType bt = ss.type();
 591       size_t this_arg_pos = buffer.size();
 592       if (ss.at_return_type()) {
 593         buffer.put(JVM_SIGNATURE_ENDFUNC);
 594       }
 595       if (arg_pos == keep_arg_pos) {
 596         buffer.write((char*) ss.raw_bytes(),
 597                      (int)   ss.raw_length());
 598       } else if (is_reference_type(bt)) {
 599         buffer.write(OBJ_SIG, OBJ_SIG_LEN);
 600       } else {
 601         if (is_subword_type(bt))
 602           bt = T_INT;
 603         buffer.put(type2char(bt));
 604       }
 605       arg_pos++;
 606     }
 607     const char* sigstr =       buffer.base();
 608     int         siglen = (int) buffer.size();
 609     bsig = SymbolTable::new_symbol(sigstr, siglen);
 610   }
 611   assert(is_basic_type_signature(bsig) ||
 612          // detune assert in case the injected argument is not a basic type:
 613          keep_last_arg, "");
 614   return bsig;
 615 }
 616 
 617 void MethodHandles::print_as_basic_type_signature_on(outputStream* st,
 618                                                      Symbol* sig,
 619                                                      bool keep_arrays,
 620                                                      bool keep_basic_names) {
 621   st = st ? st : tty;
 622   int len  = sig->utf8_length();
 623   int array = 0;
 624   bool prev_type = false;
 625   for (int i = 0; i < len; i++) {
 626     char ch = sig->char_at(i);
 627     switch (ch) {
 628     case JVM_SIGNATURE_FUNC:
 629     case JVM_SIGNATURE_ENDFUNC:
 630       prev_type = false;
 631       st->put(ch);
 632       continue;
 633     case JVM_SIGNATURE_ARRAY:
 634       if (!keep_basic_names && keep_arrays)
 635         st->put(ch);
 636       array++;
 637       continue;
 638     case JVM_SIGNATURE_CLASS:
 639       {
 640         if (prev_type)  st->put(',');
 641         int start = i+1, slash = start;
 642         while (++i < len && (ch = sig->char_at(i)) != JVM_SIGNATURE_ENDCLASS) {
 643           if (ch == JVM_SIGNATURE_SLASH || ch == JVM_SIGNATURE_DOT || ch == '$')  slash = i+1;
 644         }
 645         if (slash < i)  start = slash;
 646         if (!keep_basic_names) {
 647           st->put(JVM_SIGNATURE_CLASS);
 648         } else {
 649           for (int j = start; j < i; j++)
 650             st->put(sig->char_at(j));
 651           prev_type = true;
 652         }
 653         break;
 654       }
 655     default:
 656       {
 657         if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {
 658           ch = JVM_SIGNATURE_ARRAY;
 659           array = 0;
 660         }
 661         if (prev_type)  st->put(',');
 662         const char* n = NULL;
 663         if (keep_basic_names)
 664           n = type2name(char2type(ch));
 665         if (n == NULL) {
 666           // unknown letter, or we don't want to know its name
 667           st->put(ch);
 668         } else {
 669           st->print("%s", n);
 670           prev_type = true;
 671         }
 672         break;
 673       }
 674     }
 675     // Switch break goes here to take care of array suffix:
 676     if (prev_type) {
 677       while (array > 0) {
 678         st->print("[]");
 679         --array;
 680       }
 681     }
 682     array = 0;
 683   }
 684 }
 685 
 686 
 687 
 688 static oop object_java_mirror() {
 689   return SystemDictionary::Object_klass()->java_mirror();
 690 }
 691 
 692 oop MethodHandles::field_name_or_null(Symbol* s) {
 693   if (s == NULL)  return NULL;
 694   return StringTable::lookup(s);
 695 }
 696 
 697 oop MethodHandles::field_signature_type_or_null(Symbol* s) {
 698   if (s == NULL)  return NULL;
 699   BasicType bt = FieldType::basic_type(s);
 700   if (is_java_primitive(bt)) {
 701     assert(s->utf8_length() == 1, "");
 702     return java_lang_Class::primitive_mirror(bt);
 703   }
 704   // Here are some more short cuts for common types.
 705   // They are optional, since reference types can be resolved lazily.
 706   if (bt == T_OBJECT) {
 707     if (s == vmSymbols::object_signature()) {
 708       return object_java_mirror();
 709     } else if (s == vmSymbols::class_signature()) {
 710       return SystemDictionary::Class_klass()->java_mirror();
 711     } else if (s == vmSymbols::string_signature()) {
 712       return SystemDictionary::String_klass()->java_mirror();
 713     }
 714   }
 715   return NULL;
 716 }
 717 
 718 
 719 // An unresolved member name is a mere symbolic reference.
 720 // Resolving it plants a vmtarget/vmindex in it,
 721 // which refers directly to JVM internals.
 722 Handle MethodHandles::resolve_MemberName(Handle mname, Klass* caller,
 723                                          bool speculative_resolve, TRAPS) {
 724   Handle empty;
 725   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
 726 
 727   if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {
 728     // Already resolved.
 729     DEBUG_ONLY(int vmindex = java_lang_invoke_MemberName::vmindex(mname()));
 730     assert(vmindex >= Method::nonvirtual_vtable_index, "");
 731     return mname;
 732   }
 733 
 734   Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));
 735   Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));
 736   Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));
 737   int    flags    =       java_lang_invoke_MemberName::flags(mname());
 738   int    ref_kind =       (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
 739   if (!ref_kind_is_valid(ref_kind)) {
 740     THROW_MSG_(vmSymbols::java_lang_InternalError(), "obsolete MemberName format", empty);
 741   }
 742 
 743   DEBUG_ONLY(int old_vmindex);
 744   assert((old_vmindex = java_lang_invoke_MemberName::vmindex(mname())) == 0, "clean input");
 745 
 746   if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {
 747     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve", empty);
 748   }
 749 
 750   InstanceKlass* defc = NULL;
 751   {
 752     Klass* defc_klass = java_lang_Class::as_Klass(defc_oop());
 753     if (defc_klass == NULL)  return empty;  // a primitive; no resolution possible
 754     if (!defc_klass->is_instance_klass()) {
 755       if (!defc_klass->is_array_klass())  return empty;
 756       defc_klass = SystemDictionary::Object_klass();
 757     }
 758     defc = InstanceKlass::cast(defc_klass);
 759   }
 760   if (defc == NULL) {
 761     THROW_MSG_(vmSymbols::java_lang_InternalError(), "primitive class", empty);
 762   }
 763   defc->link_class(CHECK_(empty));  // possible safepoint
 764 
 765   // convert the external string name to an internal symbol
 766   TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());
 767   if (name == NULL)  return empty;  // no such name
 768   if (name == vmSymbols::class_initializer_name())
 769     return empty; // illegal name
 770 
 771   vmIntrinsics::ID mh_invoke_id = vmIntrinsics::_none;
 772   if ((flags & ALL_KINDS) == IS_METHOD &&
 773       (defc == SystemDictionary::MethodHandle_klass() || defc == SystemDictionary::VarHandle_klass()) &&
 774       (ref_kind == JVM_REF_invokeVirtual ||
 775        ref_kind == JVM_REF_invokeSpecial ||
 776        // static invocation mode is required for _linkToVirtual, etc.:
 777        ref_kind == JVM_REF_invokeStatic)) {
 778     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
 779     if (iid != vmIntrinsics::_none &&
 780         ((ref_kind == JVM_REF_invokeStatic) == is_signature_polymorphic_static(iid))) {
 781       // Virtual methods invoke and invokeExact, plus internal invokers like _invokeBasic.
 782       // For a static reference it could an internal linkage routine like _linkToVirtual, etc.
 783       mh_invoke_id = iid;
 784     }
 785   }
 786 
 787   // convert the external string or reflective type to an internal signature
 788   TempNewSymbol type = lookup_signature(type_str(), (mh_invoke_id != vmIntrinsics::_none), CHECK_(empty));
 789   if (type == NULL)  return empty;  // no such signature exists in the VM
 790 
 791   LinkInfo::AccessCheck access_check = caller != NULL ?
 792                                               LinkInfo::needs_access_check :
 793                                               LinkInfo::skip_access_check;
 794 
 795   // Time to do the lookup.
 796   switch (flags & ALL_KINDS) {
 797   case IS_METHOD:
 798     {
 799       CallInfo result;
 800       LinkInfo link_info(defc, name, type, caller, access_check);
 801       {
 802         assert(!HAS_PENDING_EXCEPTION, "");
 803         if (ref_kind == JVM_REF_invokeStatic) {
 804           LinkResolver::resolve_static_call(result,
 805                         link_info, false, THREAD);
 806         } else if (ref_kind == JVM_REF_invokeInterface) {
 807           LinkResolver::resolve_interface_call(result, Handle(), defc,
 808                         link_info, false, THREAD);
 809         } else if (mh_invoke_id != vmIntrinsics::_none) {
 810           assert(!is_signature_polymorphic_static(mh_invoke_id), "");
 811           LinkResolver::resolve_handle_call(result, link_info, THREAD);
 812         } else if (ref_kind == JVM_REF_invokeSpecial) {
 813           LinkResolver::resolve_special_call(result, Handle(),
 814                         link_info, THREAD);
 815         } else if (ref_kind == JVM_REF_invokeVirtual) {
 816           LinkResolver::resolve_virtual_call(result, Handle(), defc,
 817                         link_info, false, THREAD);
 818         } else {
 819           assert(false, "ref_kind=%d", ref_kind);
 820         }
 821         if (HAS_PENDING_EXCEPTION) {
 822           if (speculative_resolve) {
 823             CLEAR_PENDING_EXCEPTION;
 824           }
 825           return empty;
 826         }
 827       }
 828       if (result.resolved_appendix().not_null()) {
 829         // The resolved MemberName must not be accompanied by an appendix argument,
 830         // since there is no way to bind this value into the MemberName.
 831         // Caller is responsible to prevent this from happening.
 832         THROW_MSG_(vmSymbols::java_lang_InternalError(), "appendix", empty);
 833       }
 834       result.set_resolved_method_name(CHECK_(empty));
 835       oop mname2 = init_method_MemberName(mname, result);
 836       return Handle(THREAD, mname2);
 837     }
 838   case IS_CONSTRUCTOR:
 839     {
 840       CallInfo result;
 841       LinkInfo link_info(defc, name, type, caller, access_check);
 842       {
 843         assert(!HAS_PENDING_EXCEPTION, "");
 844         if (name == vmSymbols::object_initializer_name()) {
 845           LinkResolver::resolve_special_call(result, Handle(), link_info, THREAD);
 846         } else {
 847           break;                // will throw after end of switch
 848         }
 849         if (HAS_PENDING_EXCEPTION) {
 850           if (speculative_resolve) {
 851             CLEAR_PENDING_EXCEPTION;
 852           }
 853           return empty;
 854         }
 855       }
 856       assert(result.is_statically_bound(), "");
 857       result.set_resolved_method_name(CHECK_(empty));
 858       oop mname2 = init_method_MemberName(mname, result);
 859       return Handle(THREAD, mname2);
 860     }
 861   case IS_FIELD:
 862     {
 863       fieldDescriptor result; // find_field initializes fd if found
 864       {
 865         assert(!HAS_PENDING_EXCEPTION, "");
 866         LinkInfo link_info(defc, name, type, caller, LinkInfo::skip_access_check);
 867         LinkResolver::resolve_field(result, link_info, Bytecodes::_nop, false, THREAD);
 868         if (HAS_PENDING_EXCEPTION) {
 869           if (speculative_resolve) {
 870             CLEAR_PENDING_EXCEPTION;
 871           }
 872           return empty;
 873         }
 874       }
 875       oop mname2 = init_field_MemberName(mname, result, ref_kind_is_setter(ref_kind));
 876       return Handle(THREAD, mname2);
 877     }
 878   default:
 879     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
 880   }
 881 
 882   return empty;
 883 }
 884 
 885 // Conversely, a member name which is only initialized from JVM internals
 886 // may have null defc, name, and type fields.
 887 // Resolving it plants a vmtarget/vmindex in it,
 888 // which refers directly to JVM internals.
 889 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
 890   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
 891 
 892   bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);
 893   bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);
 894   bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);
 895   int flags      = java_lang_invoke_MemberName::flags(mname());
 896 
 897   if (suppress != 0) {
 898     if (suppress & _suppress_defc)  have_defc = true;
 899     if (suppress & _suppress_name)  have_name = true;
 900     if (suppress & _suppress_type)  have_type = true;
 901   }
 902 
 903   if (have_defc && have_name && have_type)  return;  // nothing needed
 904 
 905   switch (flags & ALL_KINDS) {
 906   case IS_METHOD:
 907   case IS_CONSTRUCTOR:
 908     {
 909       Method* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
 910       if (vmtarget == NULL) {
 911         THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
 912       }
 913       methodHandle m(THREAD, vmtarget);
 914       DEBUG_ONLY(vmtarget = NULL);  // safety
 915       if (!have_defc) {
 916         InstanceKlass* defc = m->method_holder();
 917         java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
 918       }
 919       if (!have_name) {
 920         //not java_lang_String::create_from_symbol; let's intern member names
 921         oop name = StringTable::intern(m->name(), CHECK);
 922         java_lang_invoke_MemberName::set_name(mname(), name);
 923       }
 924       if (!have_type) {
 925         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
 926         java_lang_invoke_MemberName::set_type(mname(), type());
 927       }
 928       return;
 929     }
 930   case IS_FIELD:
 931     {
 932       oop clazz = java_lang_invoke_MemberName::clazz(mname());
 933       if (clazz == NULL) {
 934         THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand (as field)");
 935       }
 936       InstanceKlass* defc = InstanceKlass::cast(java_lang_Class::as_Klass(clazz));
 937       DEBUG_ONLY(clazz = NULL);  // safety
 938       int vmindex  = java_lang_invoke_MemberName::vmindex(mname());
 939       bool is_static = ((flags & JVM_ACC_STATIC) != 0);
 940       fieldDescriptor fd; // find_field initializes fd if found
 941       if (!defc->find_field_from_offset(vmindex, is_static, &fd))
 942         break;                  // cannot expand
 943       if (!have_name) {
 944         //not java_lang_String::create_from_symbol; let's intern member names
 945         oop name = StringTable::intern(fd.name(), CHECK);
 946         java_lang_invoke_MemberName::set_name(mname(), name);
 947       }
 948       if (!have_type) {
 949         // If it is a primitive field type, don't mess with short strings like "I".
 950         Handle type (THREAD, field_signature_type_or_null(fd.signature()));
 951         if (type.is_null()) {
 952           type = java_lang_String::create_from_symbol(fd.signature(), CHECK);
 953         }
 954         java_lang_invoke_MemberName::set_type(mname(), type());
 955       }
 956       return;
 957     }
 958   }
 959   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 960 }
 961 
 962 int MethodHandles::find_MemberNames(Klass* k,
 963                                     Symbol* name, Symbol* sig,
 964                                     int mflags, Klass* caller,
 965                                     int skip, objArrayHandle results, TRAPS) {
 966   // %%% take caller into account!
 967 
 968   Thread* thread = Thread::current();
 969 
 970   if (k == NULL || !k->is_instance_klass())  return -1;
 971 
 972   int rfill = 0, rlimit = results->length(), rskip = skip;
 973   // overflow measurement:
 974   int overflow = 0, overflow_limit = MAX2(1000, rlimit);
 975 
 976   int match_flags = mflags;
 977   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
 978   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);
 979   bool local_only = !(search_superc | search_intfc);
 980 
 981   if (name != NULL) {
 982     if (name->utf8_length() == 0)  return 0; // a match is not possible
 983   }
 984   if (sig != NULL) {
 985     if (sig->utf8_length() == 0)  return 0; // a match is not possible
 986     if (sig->char_at(0) == JVM_SIGNATURE_FUNC)
 987       match_flags &= ~(IS_FIELD | IS_TYPE);
 988     else
 989       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
 990   }
 991 
 992   if ((match_flags & IS_TYPE) != 0) {
 993     // NYI, and Core Reflection works quite well for this query
 994   }
 995 
 996   if ((match_flags & IS_FIELD) != 0) {
 997     InstanceKlass* ik = InstanceKlass::cast(k);
 998     for (FieldStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {
 999       if (name != NULL && st.name() != name)
1000           continue;
1001       if (sig != NULL && st.signature() != sig)
1002         continue;
1003       // passed the filters
1004       if (rskip > 0) {
1005         --rskip;
1006       } else if (rfill < rlimit) {
1007         Handle result(thread, results->obj_at(rfill++));
1008         if (!java_lang_invoke_MemberName::is_instance(result()))
1009           return -99;  // caller bug!
1010         oop saved = MethodHandles::init_field_MemberName(result, st.field_descriptor());
1011         if (saved != result())
1012           results->obj_at_put(rfill-1, saved);  // show saved instance to user
1013       } else if (++overflow >= overflow_limit) {
1014         match_flags = 0; break; // got tired of looking at overflow
1015       }
1016     }
1017   }
1018 
1019   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
1020     // watch out for these guys:
1021     Symbol* init_name   = vmSymbols::object_initializer_name();
1022     Symbol* clinit_name = vmSymbols::class_initializer_name();
1023     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>
1024     bool negate_name_test = false;
1025     // fix name so that it captures the intention of IS_CONSTRUCTOR
1026     if (!(match_flags & IS_METHOD)) {
1027       // constructors only
1028       if (name == NULL) {
1029         name = init_name;
1030       } else if (name != init_name) {
1031         return 0;               // no constructors of this method name
1032       }
1033     } else if (!(match_flags & IS_CONSTRUCTOR)) {
1034       // methods only
1035       if (name == NULL) {
1036         name = init_name;
1037         negate_name_test = true; // if we see the name, we *omit* the entry
1038       } else if (name == init_name) {
1039         return 0;               // no methods of this constructor name
1040       }
1041     } else {
1042       // caller will accept either sort; no need to adjust name
1043     }
1044     InstanceKlass* ik = InstanceKlass::cast(k);
1045     for (MethodStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {
1046       Method* m = st.method();
1047       Symbol* m_name = m->name();
1048       if (m_name == clinit_name)
1049         continue;
1050       if (name != NULL && ((m_name != name) ^ negate_name_test))
1051           continue;
1052       if (sig != NULL && m->signature() != sig)
1053         continue;
1054       // passed the filters
1055       if (rskip > 0) {
1056         --rskip;
1057       } else if (rfill < rlimit) {
1058         Handle result(thread, results->obj_at(rfill++));
1059         if (!java_lang_invoke_MemberName::is_instance(result()))
1060           return -99;  // caller bug!
1061         CallInfo info(m, NULL, CHECK_0);
1062         oop saved = MethodHandles::init_method_MemberName(result, info);
1063         if (saved != result())
1064           results->obj_at_put(rfill-1, saved);  // show saved instance to user
1065       } else if (++overflow >= overflow_limit) {
1066         match_flags = 0; break; // got tired of looking at overflow
1067       }
1068     }
1069   }
1070 
1071   // return number of elements we at leasted wanted to initialize
1072   return rfill + overflow;
1073 }
1074 
1075 void MethodHandles::add_dependent_nmethod(oop call_site, nmethod* nm) {
1076   assert_locked_or_safepoint(CodeCache_lock);
1077 
1078   oop context = java_lang_invoke_CallSite::context_no_keepalive(call_site);
1079   DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1080   // Try to purge stale entries on updates.
1081   // Since GC doesn't clean dependency contexts rooted at CallSiteContext objects,
1082   // in order to avoid memory leak, stale entries are purged whenever a dependency list
1083   // is changed (both on addition and removal). Though memory reclamation is delayed,
1084   // it avoids indefinite memory usage growth.
1085   deps.add_dependent_nmethod(nm);
1086 }
1087 
1088 void MethodHandles::remove_dependent_nmethod(oop call_site, nmethod* nm) {
1089   assert_locked_or_safepoint(CodeCache_lock);
1090 
1091   oop context = java_lang_invoke_CallSite::context_no_keepalive(call_site);
1092   DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1093   deps.remove_dependent_nmethod(nm);
1094 }
1095 
1096 void MethodHandles::clean_dependency_context(oop call_site) {
1097   oop context = java_lang_invoke_CallSite::context_no_keepalive(call_site);
1098   DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1099   deps.clean_unloading_dependents();
1100 }
1101 
1102 void MethodHandles::flush_dependent_nmethods(Handle call_site, Handle target) {
1103   assert_lock_strong(Compile_lock);
1104 
1105   int marked = 0;
1106   CallSiteDepChange changes(call_site, target);
1107   {
1108     NoSafepointVerifier nsv;
1109     MutexLocker mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1110 
1111     oop context = java_lang_invoke_CallSite::context_no_keepalive(call_site());
1112     DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1113     marked = deps.mark_dependent_nmethods(changes);
1114   }
1115   if (marked > 0) {
1116     // At least one nmethod has been marked for deoptimization.
1117     Deoptimization::deoptimize_all_marked();
1118   }
1119 }
1120 
1121 void MethodHandles::trace_method_handle_interpreter_entry(MacroAssembler* _masm, vmIntrinsics::ID iid) {
1122   if (TraceMethodHandles) {
1123     const char* name = vmIntrinsics::name_at(iid);
1124     if (*name == '_')  name += 1;
1125     const size_t len = strlen(name) + 50;
1126     char* qname = NEW_C_HEAP_ARRAY(char, len, mtInternal);
1127     const char* suffix = "";
1128     if (is_signature_polymorphic(iid)) {
1129       if (is_signature_polymorphic_static(iid))
1130         suffix = "/static";
1131       else
1132         suffix = "/private";
1133     }
1134     jio_snprintf(qname, len, "MethodHandle::interpreter_entry::%s%s", name, suffix);
1135     trace_method_handle(_masm, qname);
1136     // Note:  Don't free the allocated char array because it's used
1137     // during runtime.
1138   }
1139 }
1140 
1141 //
1142 // Here are the native methods in java.lang.invoke.MethodHandleNatives
1143 // They are the private interface between this JVM and the HotSpot-specific
1144 // Java code that implements JSR 292 method handles.
1145 //
1146 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way
1147 // that intrinsic (non-JNI) native methods are defined in HotSpot.
1148 //
1149 
1150 #ifndef PRODUCT
1151 #define EACH_NAMED_CON(template, requirement) \
1152     template(java_lang_invoke_MemberName,MN_IS_METHOD) \
1153     template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \
1154     template(java_lang_invoke_MemberName,MN_IS_FIELD) \
1155     template(java_lang_invoke_MemberName,MN_IS_TYPE) \
1156     template(java_lang_invoke_MemberName,MN_CALLER_SENSITIVE) \
1157     template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \
1158     template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \
1159     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_SHIFT) \
1160     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_MASK) \
1161     template(java_lang_invoke_MemberName,MN_NESTMATE_CLASS) \
1162     template(java_lang_invoke_MemberName,MN_HIDDEN_CLASS) \
1163     template(java_lang_invoke_MemberName,MN_WEAK_CLASS) \
1164     template(java_lang_invoke_MemberName,MN_ACCESS_VM_ANNOTATIONS) \
1165     /*end*/
1166 
1167 #define IGNORE_REQ(req_expr) /* req_expr */
1168 #define ONE_PLUS(scope,value) 1+
1169 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS, IGNORE_REQ) 0;
1170 #define VALUE_COMMA(scope,value) scope::value,
1171 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA, IGNORE_REQ) 0 };
1172 #define STRING_NULL(scope,value) #value "\0"
1173 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL, IGNORE_REQ) };
1174 
1175 static bool advertise_con_value(int which) {
1176   if (which < 0)  return false;
1177   bool ok = true;
1178   int count = 0;
1179 #define INC_COUNT(scope,value) \
1180   ++count;
1181 #define CHECK_REQ(req_expr) \
1182   if (which < count)  return ok; \
1183   ok = (req_expr);
1184   EACH_NAMED_CON(INC_COUNT, CHECK_REQ);
1185 #undef INC_COUNT
1186 #undef CHECK_REQ
1187   assert(count == con_value_count, "");
1188   if (which < count)  return ok;
1189   return false;
1190 }
1191 
1192 #undef ONE_PLUS
1193 #undef VALUE_COMMA
1194 #undef STRING_NULL
1195 #undef EACH_NAMED_CON
1196 #endif // PRODUCT
1197 
1198 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
1199 #ifndef PRODUCT
1200   if (advertise_con_value(which)) {
1201     assert(which >= 0 && which < con_value_count, "");
1202     int con = con_values[which];
1203     objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));
1204     if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
1205       const char* str = &con_names[0];
1206       for (int i = 0; i < which; i++)
1207         str += strlen(str) + 1;   // skip name and null
1208       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);  // possible safepoint
1209       box->obj_at_put(0, name);
1210     }
1211     return con;
1212   }
1213 #endif
1214   return 0;
1215 }
1216 JVM_END
1217 
1218 // void init(MemberName self, AccessibleObject ref)
1219 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
1220   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1221   if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
1222   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1223   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
1224   MethodHandles::init_MemberName(mname, target, CHECK);
1225 }
1226 JVM_END
1227 
1228 // void expand(MemberName self)
1229 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1230   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1231   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1232   MethodHandles::expand_MemberName(mname, 0, CHECK);
1233 }
1234 JVM_END
1235 
1236 // void resolve(MemberName self, Class<?> caller)
1237 JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh,
1238     jboolean speculative_resolve)) {
1239   if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }
1240   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1241 
1242   // The trusted Java code that calls this method should already have performed
1243   // access checks on behalf of the given caller.  But, we can verify this.
1244   if (VerifyMethodHandles && caller_jh != NULL &&
1245       java_lang_invoke_MemberName::clazz(mname()) != NULL) {
1246     Klass* reference_klass = java_lang_Class::as_Klass(java_lang_invoke_MemberName::clazz(mname()));
1247     if (reference_klass != NULL && reference_klass->is_objArray_klass()) {
1248       reference_klass = ObjArrayKlass::cast(reference_klass)->bottom_klass();
1249     }
1250 
1251     // Reflection::verify_class_access can only handle instance classes.
1252     if (reference_klass != NULL && reference_klass->is_instance_klass()) {
1253       // Emulate LinkResolver::check_klass_accessability.
1254       Klass* caller = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
1255       if (caller != SystemDictionary::Object_klass()
1256           && Reflection::verify_class_access(caller,
1257                                              InstanceKlass::cast(reference_klass),
1258                                              true) != Reflection::ACCESS_OK) {
1259         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), reference_klass->external_name());
1260       }
1261     }
1262   }
1263 
1264   Klass* caller = caller_jh == NULL ? NULL :
1265                      java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
1266   Handle resolved = MethodHandles::resolve_MemberName(mname, caller, speculative_resolve == JNI_TRUE,
1267                                                       CHECK_NULL);
1268 
1269   if (resolved.is_null()) {
1270     int flags = java_lang_invoke_MemberName::flags(mname());
1271     int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
1272     if (!MethodHandles::ref_kind_is_valid(ref_kind)) {
1273       THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "obsolete MemberName format");
1274     }
1275     if (speculative_resolve) {
1276       assert(!HAS_PENDING_EXCEPTION, "No exceptions expected when resolving speculatively");
1277       return NULL;
1278     }
1279     if ((flags & ALL_KINDS) == IS_FIELD) {
1280       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchFieldError(), "field resolution failed");
1281     } else if ((flags & ALL_KINDS) == IS_METHOD ||
1282                (flags & ALL_KINDS) == IS_CONSTRUCTOR) {
1283       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), "method resolution failed");
1284     } else {
1285       THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "resolution failed");
1286     }
1287   }
1288 
1289   return JNIHandles::make_local(THREAD, resolved());
1290 }
1291 JVM_END
1292 
1293 static jlong find_member_field_offset(oop mname, bool must_be_static, TRAPS) {
1294   if (mname == NULL ||
1295       java_lang_invoke_MemberName::clazz(mname) == NULL) {
1296     THROW_MSG_0(vmSymbols::java_lang_InternalError(), "mname not resolved");
1297   } else {
1298     int flags = java_lang_invoke_MemberName::flags(mname);
1299     if ((flags & IS_FIELD) != 0 &&
1300         (must_be_static
1301          ? (flags & JVM_ACC_STATIC) != 0
1302          : (flags & JVM_ACC_STATIC) == 0)) {
1303       int vmindex = java_lang_invoke_MemberName::vmindex(mname);
1304       return (jlong) vmindex;
1305     }
1306   }
1307   const char* msg = (must_be_static ? "static field required" : "non-static field required");
1308   THROW_MSG_0(vmSymbols::java_lang_InternalError(), msg);
1309   return 0;
1310 }
1311 
1312 JVM_ENTRY(jlong, MHN_objectFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1313   return find_member_field_offset(JNIHandles::resolve(mname_jh), false, THREAD);
1314 }
1315 JVM_END
1316 
1317 JVM_ENTRY(jlong, MHN_staticFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1318   return find_member_field_offset(JNIHandles::resolve(mname_jh), true, THREAD);
1319 }
1320 JVM_END
1321 
1322 JVM_ENTRY(jobject, MHN_staticFieldBase(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1323   // use the other function to perform sanity checks:
1324   jlong ignore = find_member_field_offset(JNIHandles::resolve(mname_jh), true, CHECK_NULL);
1325   oop clazz = java_lang_invoke_MemberName::clazz(JNIHandles::resolve_non_null(mname_jh));
1326   return JNIHandles::make_local(THREAD, clazz);
1327 }
1328 JVM_END
1329 
1330 JVM_ENTRY(jobject, MHN_getMemberVMInfo(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1331   if (mname_jh == NULL)  return NULL;
1332   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1333   intptr_t vmindex  = java_lang_invoke_MemberName::vmindex(mname());
1334   objArrayHandle result = oopFactory::new_objArray_handle(SystemDictionary::Object_klass(), 2, CHECK_NULL);
1335   jvalue vmindex_value; vmindex_value.j = (long)vmindex;
1336   oop x = java_lang_boxing_object::create(T_LONG, &vmindex_value, CHECK_NULL);
1337   result->obj_at_put(0, x);
1338 
1339   int flags = java_lang_invoke_MemberName::flags(mname());
1340   if ((flags & IS_FIELD) != 0) {
1341     x = java_lang_invoke_MemberName::clazz(mname());
1342   } else {
1343     Method* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
1344     assert(vmtarget != NULL && vmtarget->is_method(), "vmtarget is only method");
1345     x = mname();
1346   }
1347   result->obj_at_put(1, x);
1348   return JNIHandles::make_local(env, result());
1349 }
1350 JVM_END
1351 
1352 
1353 
1354 //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
1355 //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
1356 JVM_ENTRY(jint, MHN_getMembers(JNIEnv *env, jobject igcls,
1357                                jclass clazz_jh, jstring name_jh, jstring sig_jh,
1358                                int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
1359   if (clazz_jh == NULL || results_jh == NULL)  return -1;
1360   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz_jh));
1361 
1362   objArrayHandle results(THREAD, (objArrayOop) JNIHandles::resolve(results_jh));
1363   if (results.is_null() || !results->is_objArray())  return -1;
1364 
1365   TempNewSymbol name = NULL;
1366   TempNewSymbol sig = NULL;
1367   if (name_jh != NULL) {
1368     name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
1369     if (name == NULL)  return 0; // a match is not possible
1370   }
1371   if (sig_jh != NULL) {
1372     sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
1373     if (sig == NULL)  return 0; // a match is not possible
1374   }
1375 
1376   Klass* caller = NULL;
1377   if (caller_jh != NULL) {
1378     oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
1379     if (!java_lang_Class::is_instance(caller_oop))  return -1;
1380     caller = java_lang_Class::as_Klass(caller_oop);
1381   }
1382 
1383   if (name != NULL && sig != NULL && results.not_null()) {
1384     // try a direct resolve
1385     // %%% TO DO
1386   }
1387 
1388   int res = MethodHandles::find_MemberNames(k, name, sig, mflags,
1389                                             caller, skip, results, CHECK_0);
1390   // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
1391   return res;
1392 }
1393 JVM_END
1394 
1395 JVM_ENTRY(void, MHN_setCallSiteTargetNormal(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1396   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1397   Handle target   (THREAD, JNIHandles::resolve_non_null(target_jh));
1398   {
1399     // Walk all nmethods depending on this call site.
1400     MutexLocker mu(Compile_lock, thread);
1401     MethodHandles::flush_dependent_nmethods(call_site, target);
1402     java_lang_invoke_CallSite::set_target(call_site(), target());
1403   }
1404 }
1405 JVM_END
1406 
1407 JVM_ENTRY(void, MHN_setCallSiteTargetVolatile(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1408   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1409   Handle target   (THREAD, JNIHandles::resolve_non_null(target_jh));
1410   {
1411     // Walk all nmethods depending on this call site.
1412     MutexLocker mu(Compile_lock, thread);
1413     MethodHandles::flush_dependent_nmethods(call_site, target);
1414     java_lang_invoke_CallSite::set_target_volatile(call_site(), target());
1415   }
1416 }
1417 JVM_END
1418 
1419 JVM_ENTRY(void, MHN_copyOutBootstrapArguments(JNIEnv* env, jobject igcls,
1420                                               jobject caller_jh, jintArray index_info_jh,
1421                                               jint start, jint end,
1422                                               jobjectArray buf_jh, jint pos,
1423                                               jboolean resolve, jobject ifna_jh)) {
1424   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller_jh));
1425   if (caller_k == NULL || !caller_k->is_instance_klass()) {
1426       THROW_MSG(vmSymbols::java_lang_InternalError(), "bad caller");
1427   }
1428   InstanceKlass* caller = InstanceKlass::cast(caller_k);
1429   typeArrayOop index_info_oop = (typeArrayOop) JNIHandles::resolve(index_info_jh);
1430   if (index_info_oop == NULL ||
1431       index_info_oop->klass() != Universe::intArrayKlassObj() ||
1432       typeArrayOop(index_info_oop)->length() < 2) {
1433       THROW_MSG(vmSymbols::java_lang_InternalError(), "bad index info (0)");
1434   }
1435   typeArrayHandle index_info(THREAD, index_info_oop);
1436   int bss_index_in_pool = index_info->int_at(1);
1437   // While we are here, take a quick look at the index info:
1438   if (bss_index_in_pool <= 0 ||
1439       bss_index_in_pool >= caller->constants()->length() ||
1440       index_info->int_at(0)
1441       != caller->constants()->bootstrap_argument_count_at(bss_index_in_pool)) {
1442       THROW_MSG(vmSymbols::java_lang_InternalError(), "bad index info (1)");
1443   }
1444   objArrayHandle buf(THREAD, (objArrayOop) JNIHandles::resolve(buf_jh));
1445   if (start < 0) {
1446     for (int pseudo_index = -4; pseudo_index < 0; pseudo_index++) {
1447       if (start == pseudo_index) {
1448         if (start >= end || 0 > pos || pos >= buf->length())  break;
1449         oop pseudo_arg = NULL;
1450         switch (pseudo_index) {
1451         case -4:  // bootstrap method
1452           {
1453             int bsm_index = caller->constants()->bootstrap_method_ref_index_at(bss_index_in_pool);
1454             pseudo_arg = caller->constants()->resolve_possibly_cached_constant_at(bsm_index, CHECK);
1455             break;
1456           }
1457         case -3:  // name
1458           {
1459             Symbol* name = caller->constants()->name_ref_at(bss_index_in_pool);
1460             Handle str = java_lang_String::create_from_symbol(name, CHECK);
1461             pseudo_arg = str();
1462             break;
1463           }
1464         case -2:  // type
1465           {
1466             Symbol* type = caller->constants()->signature_ref_at(bss_index_in_pool);
1467             Handle th;
1468             if (type->char_at(0) == JVM_SIGNATURE_FUNC) {
1469               th = SystemDictionary::find_method_handle_type(type, caller, CHECK);
1470             } else {
1471               th = SystemDictionary::find_java_mirror_for_type(type, caller, SignatureStream::NCDFError, CHECK);
1472             }
1473             pseudo_arg = th();
1474             break;
1475           }
1476         case -1:  // argument count
1477           {
1478             int argc = caller->constants()->bootstrap_argument_count_at(bss_index_in_pool);
1479             jvalue argc_value; argc_value.i = (jint)argc;
1480             pseudo_arg = java_lang_boxing_object::create(T_INT, &argc_value, CHECK);
1481             break;
1482           }
1483         }
1484 
1485         // Store the pseudo-argument, and advance the pointers.
1486         buf->obj_at_put(pos++, pseudo_arg);
1487         ++start;
1488       }
1489     }
1490     // When we are done with this there may be regular arguments to process too.
1491   }
1492   Handle ifna(THREAD, JNIHandles::resolve(ifna_jh));
1493   caller->constants()->
1494     copy_bootstrap_arguments_at(bss_index_in_pool,
1495                                 start, end, buf, pos,
1496                                 (resolve == JNI_TRUE), ifna, CHECK);
1497 }
1498 JVM_END
1499 
1500 // It is called by a Cleaner object which ensures that dropped CallSites properly
1501 // deallocate their dependency information.
1502 JVM_ENTRY(void, MHN_clearCallSiteContext(JNIEnv* env, jobject igcls, jobject context_jh)) {
1503   Handle context(THREAD, JNIHandles::resolve_non_null(context_jh));
1504   {
1505     // Walk all nmethods depending on this call site.
1506     MutexLocker mu1(Compile_lock, thread);
1507 
1508     int marked = 0;
1509     {
1510       NoSafepointVerifier nsv;
1511       MutexLocker mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1512       DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context());
1513       marked = deps.remove_all_dependents();
1514     }
1515     if (marked > 0) {
1516       // At least one nmethod has been marked for deoptimization
1517       Deoptimization::deoptimize_all_marked();
1518     }
1519   }
1520 }
1521 JVM_END
1522 
1523 /*
1524  * Return the class data from the injected classData field of the given lookup class
1525  */
1526 JVM_ENTRY(jobject, MHN_classData(JNIEnv *env, jobject igcls, jclass lookup))
1527   if (lookup == NULL) {
1528     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
1529   }
1530   oop mirror = JNIHandles::resolve_non_null(lookup);
1531   return (jobject) JNIHandles::make_local(env, java_lang_Class::class_data(mirror));
1532 JVM_END
1533 
1534 /**
1535  * Throws a java/lang/UnsupportedOperationException unconditionally.
1536  * This is required by the specification of MethodHandle.invoke if
1537  * invoked directly.
1538  */
1539 JVM_ENTRY(jobject, MH_invoke_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1540   THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invoke cannot be invoked reflectively");
1541   return NULL;
1542 }
1543 JVM_END
1544 
1545 /**
1546  * Throws a java/lang/UnsupportedOperationException unconditionally.
1547  * This is required by the specification of MethodHandle.invokeExact if
1548  * invoked directly.
1549  */
1550 JVM_ENTRY(jobject, MH_invokeExact_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1551   THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invokeExact cannot be invoked reflectively");
1552   return NULL;
1553 }
1554 JVM_END
1555 
1556 /// JVM_RegisterMethodHandleMethods
1557 
1558 #undef CS  // Solaris builds complain
1559 
1560 #define LANG "Ljava/lang/"
1561 #define JLINV "Ljava/lang/invoke/"
1562 
1563 #define OBJ   LANG "Object;"
1564 #define CLS   LANG "Class;"
1565 #define STRG  LANG "String;"
1566 #define CS    JLINV "CallSite;"
1567 #define MT    JLINV "MethodType;"
1568 #define MH    JLINV "MethodHandle;"
1569 #define MEM   JLINV "MemberName;"
1570 #define CTX   JLINV "MethodHandleNatives$CallSiteContext;"
1571 
1572 #define CC (char*)  /*cast a literal from (const char*)*/
1573 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1574 
1575 // These are the native methods on java.lang.invoke.MethodHandleNatives.
1576 static JNINativeMethod MHN_methods[] = {
1577   {CC "init",                      CC "(" MEM "" OBJ ")V",                   FN_PTR(MHN_init_Mem)},
1578   {CC "expand",                    CC "(" MEM ")V",                          FN_PTR(MHN_expand_Mem)},
1579   {CC "resolve",                   CC "(" MEM "" CLS "Z)" MEM,               FN_PTR(MHN_resolve_Mem)},
1580   //  static native int getNamedCon(int which, Object[] name)
1581   {CC "getNamedCon",               CC "(I[" OBJ ")I",                        FN_PTR(MHN_getNamedCon)},
1582   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
1583   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
1584   {CC "getMembers",                CC "(" CLS "" STRG "" STRG "I" CLS "I[" MEM ")I", FN_PTR(MHN_getMembers)},
1585   {CC "objectFieldOffset",         CC "(" MEM ")J",                          FN_PTR(MHN_objectFieldOffset)},
1586   {CC "setCallSiteTargetNormal",   CC "(" CS "" MH ")V",                     FN_PTR(MHN_setCallSiteTargetNormal)},
1587   {CC "setCallSiteTargetVolatile", CC "(" CS "" MH ")V",                     FN_PTR(MHN_setCallSiteTargetVolatile)},
1588   {CC "copyOutBootstrapArguments", CC "(" CLS "[III[" OBJ "IZ" OBJ ")V",     FN_PTR(MHN_copyOutBootstrapArguments)},
1589   {CC "clearCallSiteContext",      CC "(" CTX ")V",                          FN_PTR(MHN_clearCallSiteContext)},
1590   {CC "staticFieldOffset",         CC "(" MEM ")J",                          FN_PTR(MHN_staticFieldOffset)},
1591   {CC "staticFieldBase",           CC "(" MEM ")" OBJ,                        FN_PTR(MHN_staticFieldBase)},
1592   {CC "getMemberVMInfo",           CC "(" MEM ")" OBJ,                       FN_PTR(MHN_getMemberVMInfo)},
1593   {CC "classData",                 CC "(" CLS ")" OBJ,                       FN_PTR(MHN_classData)}
1594 };
1595 
1596 static JNINativeMethod MH_methods[] = {
1597   // UnsupportedOperationException throwers
1598   {CC "invoke",                    CC "([" OBJ ")" OBJ,                       FN_PTR(MH_invoke_UOE)},
1599   {CC "invokeExact",               CC "([" OBJ ")" OBJ,                       FN_PTR(MH_invokeExact_UOE)}
1600 };
1601 
1602 /**
1603  * This one function is exported, used by NativeLookup.
1604  */
1605 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
1606   assert(!MethodHandles::enabled(), "must not be enabled");
1607   assert(SystemDictionary::MethodHandle_klass() != NULL, "should be present");
1608 
1609   oop mirror = SystemDictionary::MethodHandle_klass()->java_mirror();
1610   jclass MH_class = (jclass) JNIHandles::make_local(env, mirror);
1611 
1612   {
1613     ThreadToNativeFromVM ttnfv(thread);
1614 
1615     int status = env->RegisterNatives(MHN_class, MHN_methods, sizeof(MHN_methods)/sizeof(JNINativeMethod));
1616     guarantee(status == JNI_OK && !env->ExceptionOccurred(),
1617               "register java.lang.invoke.MethodHandleNative natives");
1618 
1619     status = env->RegisterNatives(MH_class, MH_methods, sizeof(MH_methods)/sizeof(JNINativeMethod));
1620     guarantee(status == JNI_OK && !env->ExceptionOccurred(),
1621               "register java.lang.invoke.MethodHandle natives");
1622   }
1623 
1624   if (TraceInvokeDynamic) {
1625     tty->print_cr("MethodHandle support loaded (using LambdaForms)");
1626   }
1627 
1628   MethodHandles::set_enabled(true);
1629 }
1630 JVM_END