1 /*
   2  * Copyright (c) 2008, 2013, 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/symbolTable.hpp"
  27 #include "compiler/compileBroker.hpp"
  28 #include "interpreter/interpreter.hpp"
  29 #include "interpreter/oopMapCache.hpp"
  30 #include "memory/allocation.inline.hpp"
  31 #include "memory/oopFactory.hpp"
  32 #include "prims/jvmtiRedefineClassesTrace.hpp"
  33 #include "prims/methodHandles.hpp"
  34 #include "runtime/compilationPolicy.hpp"
  35 #include "runtime/javaCalls.hpp"
  36 #include "runtime/reflection.hpp"
  37 #include "runtime/signature.hpp"
  38 #include "runtime/stubRoutines.hpp"
  39 
  40 
  41 /*
  42  * JSR 292 reference implementation: method handles
  43  * The JDK 7 reference implementation represented method handle
  44  * combinations as chains.  Each link in the chain had a "vmentry"
  45  * field which pointed at a bit of assembly code which performed
  46  * one transformation before dispatching to the next link in the chain.
  47  *
  48  * The current reference implementation pushes almost all code generation
  49  * responsibility to (trusted) Java code.  A method handle contains a
  50  * pointer to its "LambdaForm", which embodies all details of the method
  51  * handle's behavior.  The LambdaForm is a normal Java object, managed
  52  * by a runtime coded in Java.
  53  */
  54 
  55 bool MethodHandles::_enabled = false; // set true after successful native linkage
  56 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;
  57 
  58 //------------------------------------------------------------------------------
  59 // MethodHandles::generate_adapters
  60 //
  61 void MethodHandles::generate_adapters() {
  62   if (!EnableInvokeDynamic || SystemDictionary::MethodHandle_klass() == NULL)  return;
  63 
  64   assert(_adapter_code == NULL, "generate only once");
  65 
  66   ResourceMark rm;
  67   TraceTime timer("MethodHandles adapters generation", TraceStartupTime);
  68   _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);
  69   if (_adapter_code == NULL)
  70     vm_exit_out_of_memory(adapter_code_size, OOM_MALLOC_ERROR,
  71                           "CodeCache: no room for MethodHandles adapters");
  72   {
  73     CodeBuffer code(_adapter_code);
  74     MethodHandlesAdapterGenerator g(&code);
  75     g.generate();
  76     code.log_section_sizes("MethodHandlesAdapterBlob");
  77   }
  78 }
  79 
  80 //------------------------------------------------------------------------------
  81 // MethodHandlesAdapterGenerator::generate
  82 //
  83 void MethodHandlesAdapterGenerator::generate() {
  84   // Generate generic method handle adapters.
  85   // Generate interpreter entries
  86   for (Interpreter::MethodKind mk = Interpreter::method_handle_invoke_FIRST;
  87        mk <= Interpreter::method_handle_invoke_LAST;
  88        mk = Interpreter::MethodKind(1 + (int)mk)) {
  89     vmIntrinsics::ID iid = Interpreter::method_handle_intrinsic(mk);
  90     StubCodeMark mark(this, "MethodHandle::interpreter_entry", vmIntrinsics::name_at(iid));
  91     address entry = MethodHandles::generate_method_handle_interpreter_entry(_masm, iid);
  92     if (entry != NULL) {
  93       Interpreter::set_entry_for_kind(mk, entry);
  94     }
  95     // If the entry is not set, it will throw AbstractMethodError.
  96   }
  97 }
  98 
  99 void MethodHandles::set_enabled(bool z) {
 100   if (_enabled != z) {
 101     guarantee(z && EnableInvokeDynamic, "can only enable once, and only if -XX:+EnableInvokeDynamic");
 102     _enabled = z;
 103   }
 104 }
 105 
 106 // MemberName support
 107 
 108 // import java_lang_invoke_MemberName.*
 109 enum {
 110   IS_METHOD            = java_lang_invoke_MemberName::MN_IS_METHOD,
 111   IS_CONSTRUCTOR       = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,
 112   IS_FIELD             = java_lang_invoke_MemberName::MN_IS_FIELD,
 113   IS_TYPE              = java_lang_invoke_MemberName::MN_IS_TYPE,
 114   CALLER_SENSITIVE     = java_lang_invoke_MemberName::MN_CALLER_SENSITIVE,
 115   REFERENCE_KIND_SHIFT = java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT,
 116   REFERENCE_KIND_MASK  = java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,
 117   SEARCH_SUPERCLASSES  = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,
 118   SEARCH_INTERFACES    = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,
 119   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE
 120 };
 121 
 122 Handle MethodHandles::new_MemberName(TRAPS) {
 123   Handle empty;
 124   instanceKlassHandle k(THREAD, SystemDictionary::MemberName_klass());
 125   if (!k->is_initialized())  k->initialize(CHECK_(empty));
 126   return Handle(THREAD, k->allocate_instance(THREAD));
 127 }
 128 
 129 oop MethodHandles::init_MemberName(Handle mname, Handle target) {
 130   Thread* thread = Thread::current();
 131   oop target_oop = target();
 132   Klass* target_klass = target_oop->klass();
 133   if (target_klass == SystemDictionary::reflect_Field_klass()) {
 134     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
 135     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()
 136     int mods  = java_lang_reflect_Field::modifiers(target_oop);
 137     oop type  = java_lang_reflect_Field::type(target_oop);
 138     oop name  = java_lang_reflect_Field::name(target_oop);
 139     KlassHandle k(thread, java_lang_Class::as_Klass(clazz));
 140     intptr_t offset = InstanceKlass::cast(k())->field_offset(slot);
 141     return init_field_MemberName(mname, k, accessFlags_from(mods), type, name, offset);
 142   } else if (target_klass == SystemDictionary::reflect_Method_klass()) {
 143     oop clazz  = java_lang_reflect_Method::clazz(target_oop);
 144     int slot   = java_lang_reflect_Method::slot(target_oop);
 145     KlassHandle k(thread, java_lang_Class::as_Klass(clazz));
 146     if (!k.is_null() && k->oop_is_instance()) {
 147       Method* m = InstanceKlass::cast(k())->method_with_idnum(slot);
 148       return init_method_MemberName(mname, m, true, k);
 149     }
 150   } else if (target_klass == SystemDictionary::reflect_Constructor_klass()) {
 151     oop clazz  = java_lang_reflect_Constructor::clazz(target_oop);
 152     int slot   = java_lang_reflect_Constructor::slot(target_oop);
 153     KlassHandle k(thread, java_lang_Class::as_Klass(clazz));
 154     if (!k.is_null() && k->oop_is_instance()) {
 155       Method* m = InstanceKlass::cast(k())->method_with_idnum(slot);
 156       return init_method_MemberName(mname, m, false, k);
 157     }
 158   } else if (target_klass == SystemDictionary::MemberName_klass()) {
 159     // Note: This only works if the MemberName has already been resolved.
 160     oop clazz        = java_lang_invoke_MemberName::clazz(target_oop);
 161     int flags        = java_lang_invoke_MemberName::flags(target_oop);
 162     Metadata* vmtarget=java_lang_invoke_MemberName::vmtarget(target_oop);
 163     intptr_t vmindex = java_lang_invoke_MemberName::vmindex(target_oop);
 164     KlassHandle k(thread, java_lang_Class::as_Klass(clazz));
 165     int ref_kind     = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
 166     if (vmtarget == NULL)  return NULL;  // not resolved
 167     if ((flags & IS_FIELD) != 0) {
 168       assert(vmtarget->is_klass(), "field vmtarget is Klass*");
 169       int basic_mods = (ref_kind_is_static(ref_kind) ? JVM_ACC_STATIC : 0);
 170       // FIXME:  how does k (receiver_limit) contribute?
 171       KlassHandle k_vmtarget(thread, (Klass*)vmtarget);
 172       return init_field_MemberName(mname, k_vmtarget, accessFlags_from(basic_mods), NULL, NULL, vmindex);
 173     } else if ((flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
 174       assert(vmtarget->is_method(), "method or constructor vmtarget is Method*");
 175       return init_method_MemberName(mname, (Method*)vmtarget, ref_kind_does_dispatch(ref_kind), k);
 176     } else {
 177       return NULL;
 178     }
 179   }
 180   return NULL;
 181 }
 182 
 183 oop MethodHandles::init_method_MemberName(Handle mname, Method* m, bool do_dispatch,
 184                                           KlassHandle receiver_limit_h) {
 185   Klass* receiver_limit = receiver_limit_h();
 186   AccessFlags mods = m->access_flags();
 187   int flags = (jushort)( mods.as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS );
 188   int vmindex = Method::nonvirtual_vtable_index; // implies never any dispatch
 189   Klass* mklass = m->method_holder();
 190   if (receiver_limit == NULL)
 191     receiver_limit = mklass;
 192   if (m->is_initializer()) {
 193     flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
 194   } else if (mods.is_static()) {
 195     flags |= IS_METHOD | (JVM_REF_invokeStatic << REFERENCE_KIND_SHIFT);
 196   } else if (receiver_limit != mklass &&
 197              !receiver_limit->is_subtype_of(mklass)) {
 198     return NULL;  // bad receiver limit
 199   } else if (do_dispatch && receiver_limit->is_interface() &&
 200              mklass->is_interface()) {
 201     flags |= IS_METHOD | (JVM_REF_invokeInterface << REFERENCE_KIND_SHIFT);
 202     receiver_limit = mklass;  // ignore passed-in limit; interfaces are interconvertible
 203     vmindex = klassItable::compute_itable_index(m);
 204   } else if (do_dispatch && mklass != receiver_limit && mklass->is_interface()) {
 205     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
 206     // it is a miranda method, so m->vtable_index is not what we want
 207     ResourceMark rm;
 208     klassVtable* vt = InstanceKlass::cast(receiver_limit)->vtable();
 209     vmindex = vt->index_of_miranda(m->name(), m->signature());
 210   } else if (!do_dispatch || m->can_be_statically_bound()) {
 211     flags |= IS_METHOD | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
 212   } else {
 213     flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
 214     vmindex = m->vtable_index();
 215   }
 216 
 217   // @CallerSensitive annotation detected
 218   if (m->caller_sensitive()) {
 219     flags |= CALLER_SENSITIVE;
 220   }
 221 
 222   oop mname_oop = mname();
 223   java_lang_invoke_MemberName::set_flags(   mname_oop, flags);
 224   java_lang_invoke_MemberName::set_vmtarget(mname_oop, m);
 225   java_lang_invoke_MemberName::set_vmindex( mname_oop, vmindex);   // vtable/itable index
 226   java_lang_invoke_MemberName::set_clazz(   mname_oop, receiver_limit->java_mirror());
 227   // Note:  name and type can be lazily computed by resolve_MemberName,
 228   // if Java code needs them as resolved String and MethodType objects.
 229   // The clazz must be eagerly stored, because it provides a GC
 230   // root to help keep alive the Method*.
 231   // If relevant, the vtable or itable value is stored as vmindex.
 232   // This is done eagerly, since it is readily available without
 233   // constructing any new objects.
 234   // TO DO: maybe intern mname_oop
 235   m->method_holder()->add_member_name(m->method_idnum(), mname);
 236 
 237   return mname();
 238 }
 239 
 240 Handle MethodHandles::init_method_MemberName(Handle mname, CallInfo& info, TRAPS) {
 241   Handle empty;
 242   if (info.resolved_appendix().not_null()) {
 243     // The resolved MemberName must not be accompanied by an appendix argument,
 244     // since there is no way to bind this value into the MemberName.
 245     // Caller is responsible to prevent this from happening.
 246     THROW_MSG_(vmSymbols::java_lang_InternalError(), "appendix", empty);
 247   }
 248   methodHandle m = info.resolved_method();
 249   KlassHandle defc = info.resolved_klass();
 250   int vmindex = Method::invalid_vtable_index;
 251   if (defc->is_interface() && m->method_holder()->is_interface()) {
 252     // static interface methods do not reference vtable or itable
 253     if (m->is_static()) {
 254       vmindex = Method::nonvirtual_vtable_index;
 255     }
 256     // interface methods invoked via invokespecial also
 257     // do not reference vtable or itable.
 258     int ref_kind = ((java_lang_invoke_MemberName::flags(mname()) >>
 259                      REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK);
 260     if (ref_kind == JVM_REF_invokeSpecial) {
 261       vmindex = Method::nonvirtual_vtable_index;
 262     }
 263     // If neither m is static nor ref_kind is invokespecial,
 264     // set it to itable index.
 265     if (vmindex == Method::invalid_vtable_index) {
 266       // LinkResolver does not report itable indexes!  (fix this?)
 267       vmindex = klassItable::compute_itable_index(m());
 268     }
 269   } else if (m->can_be_statically_bound()) {
 270     // LinkResolver reports vtable index even for final methods!
 271     vmindex = Method::nonvirtual_vtable_index;
 272   } else {
 273     vmindex = info.vtable_index();
 274   }
 275   oop res = init_method_MemberName(mname, m(), (vmindex >= 0), defc());
 276   assert(res == NULL || (java_lang_invoke_MemberName::vmindex(res) == vmindex), "");
 277   return Handle(THREAD, res);
 278 }
 279 
 280 oop MethodHandles::init_field_MemberName(Handle mname, KlassHandle field_holder,
 281                                          AccessFlags mods, oop type, oop name,
 282                                          intptr_t offset, bool is_setter) {
 283   int flags = (jushort)( mods.as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS );
 284   flags |= IS_FIELD | ((mods.is_static() ? JVM_REF_getStatic : JVM_REF_getField) << REFERENCE_KIND_SHIFT);
 285   if (is_setter)  flags += ((JVM_REF_putField - JVM_REF_getField) << REFERENCE_KIND_SHIFT);
 286   Metadata* vmtarget = field_holder();
 287   int vmindex  = offset;  // determines the field uniquely when combined with static bit
 288   oop mname_oop = mname();
 289   java_lang_invoke_MemberName::set_flags(mname_oop,    flags);
 290   java_lang_invoke_MemberName::set_vmtarget(mname_oop, vmtarget);
 291   java_lang_invoke_MemberName::set_vmindex(mname_oop,  vmindex);
 292   java_lang_invoke_MemberName::set_clazz(mname_oop,    field_holder->java_mirror());
 293   if (name != NULL)
 294     java_lang_invoke_MemberName::set_name(mname_oop,   name);
 295   if (type != NULL)
 296     java_lang_invoke_MemberName::set_type(mname_oop,   type);
 297   // Note:  name and type can be lazily computed by resolve_MemberName,
 298   // if Java code needs them as resolved String and Class objects.
 299   // Note that the incoming type oop might be pre-resolved (non-null).
 300   // The base clazz and field offset (vmindex) must be eagerly stored,
 301   // because they unambiguously identify the field.
 302   // Although the fieldDescriptor::_index would also identify the field,
 303   // we do not use it, because it is harder to decode.
 304   // TO DO: maybe intern mname_oop
 305   return mname();
 306 }
 307 
 308 Handle MethodHandles::init_field_MemberName(Handle mname, FieldAccessInfo& info, TRAPS) {
 309   return Handle();
 310 #if 0 // FIXME
 311   KlassHandle field_holder = info.klass();
 312   intptr_t    field_offset = info.field_offset();
 313   return init_field_MemberName(mname_oop, field_holder(),
 314                                info.access_flags(),
 315                                type, name,
 316                                field_offset, false /*is_setter*/);
 317 #endif
 318 }
 319 
 320 
 321 // JVM 2.9 Special Methods:
 322 // A method is signature polymorphic if and only if all of the following conditions hold :
 323 // * It is declared in the java.lang.invoke.MethodHandle class.
 324 // * It has a single formal parameter of type Object[].
 325 // * It has a return type of Object.
 326 // * It has the ACC_VARARGS and ACC_NATIVE flags set.
 327 bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
 328   if (klass == NULL)
 329     return false;
 330   // The following test will fail spuriously during bootstrap of MethodHandle itself:
 331   //    if (klass != SystemDictionary::MethodHandle_klass())
 332   // Test the name instead:
 333   if (klass->name() != vmSymbols::java_lang_invoke_MethodHandle())
 334     return false;
 335   Symbol* poly_sig = vmSymbols::object_array_object_signature();
 336   Method* m = InstanceKlass::cast(klass)->find_method(name, poly_sig);
 337   if (m == NULL)  return false;
 338   int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
 339   int flags = m->access_flags().as_int();
 340   return (flags & required) == required;
 341 }
 342 
 343 
 344 Symbol* MethodHandles::signature_polymorphic_intrinsic_name(vmIntrinsics::ID iid) {
 345   assert(is_signature_polymorphic_intrinsic(iid), err_msg("iid=%d", iid));
 346   switch (iid) {
 347   case vmIntrinsics::_invokeBasic:      return vmSymbols::invokeBasic_name();
 348   case vmIntrinsics::_linkToVirtual:    return vmSymbols::linkToVirtual_name();
 349   case vmIntrinsics::_linkToStatic:     return vmSymbols::linkToStatic_name();
 350   case vmIntrinsics::_linkToSpecial:    return vmSymbols::linkToSpecial_name();
 351   case vmIntrinsics::_linkToInterface:  return vmSymbols::linkToInterface_name();
 352   }
 353   assert(false, "");
 354   return 0;
 355 }
 356 
 357 int MethodHandles::signature_polymorphic_intrinsic_ref_kind(vmIntrinsics::ID iid) {
 358   switch (iid) {
 359   case vmIntrinsics::_invokeBasic:      return 0;
 360   case vmIntrinsics::_linkToVirtual:    return JVM_REF_invokeVirtual;
 361   case vmIntrinsics::_linkToStatic:     return JVM_REF_invokeStatic;
 362   case vmIntrinsics::_linkToSpecial:    return JVM_REF_invokeSpecial;
 363   case vmIntrinsics::_linkToInterface:  return JVM_REF_invokeInterface;
 364   }
 365   assert(false, err_msg("iid=%d", iid));
 366   return 0;
 367 }
 368 
 369 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Symbol* name) {
 370   vmSymbols::SID name_id = vmSymbols::find_sid(name);
 371   switch (name_id) {
 372   // The ID _invokeGeneric stands for all non-static signature-polymorphic methods, except built-ins.
 373   case vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name):           return vmIntrinsics::_invokeGeneric;
 374   // The only built-in non-static signature-polymorphic method is MethodHandle.invokeBasic:
 375   case vmSymbols::VM_SYMBOL_ENUM_NAME(invokeBasic_name):      return vmIntrinsics::_invokeBasic;
 376 
 377   // There is one static signature-polymorphic method for each JVM invocation mode.
 378   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToVirtual_name):    return vmIntrinsics::_linkToVirtual;
 379   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToStatic_name):     return vmIntrinsics::_linkToStatic;
 380   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToSpecial_name):    return vmIntrinsics::_linkToSpecial;
 381   case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToInterface_name):  return vmIntrinsics::_linkToInterface;
 382   }
 383 
 384   // Cover the case of invokeExact and any future variants of invokeFoo.
 385   Klass* mh_klass = SystemDictionary::well_known_klass(
 386                               SystemDictionary::WK_KLASS_ENUM_NAME(MethodHandle_klass) );
 387   if (mh_klass != NULL && is_method_handle_invoke_name(mh_klass, name))
 388     return vmIntrinsics::_invokeGeneric;
 389 
 390   // Note: The pseudo-intrinsic _compiledLambdaForm is never linked against.
 391   // Instead it is used to mark lambda forms bound to invokehandle or invokedynamic.
 392   return vmIntrinsics::_none;
 393 }
 394 
 395 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Klass* klass, Symbol* name) {
 396   if (klass != NULL &&
 397       klass->name() == vmSymbols::java_lang_invoke_MethodHandle()) {
 398     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
 399     if (iid != vmIntrinsics::_none)
 400       return iid;
 401     if (is_method_handle_invoke_name(klass, name))
 402       return vmIntrinsics::_invokeGeneric;
 403   }
 404   return vmIntrinsics::_none;
 405 }
 406 
 407 
 408 // convert the external string or reflective type to an internal signature
 409 Symbol* MethodHandles::lookup_signature(oop type_str, bool intern_if_not_found, TRAPS) {
 410   if (java_lang_invoke_MethodType::is_instance(type_str)) {
 411     return java_lang_invoke_MethodType::as_signature(type_str, intern_if_not_found, CHECK_NULL);
 412   } else if (java_lang_Class::is_instance(type_str)) {
 413     return java_lang_Class::as_signature(type_str, false, CHECK_NULL);
 414   } else if (java_lang_String::is_instance(type_str)) {
 415     if (intern_if_not_found) {
 416       return java_lang_String::as_symbol(type_str, CHECK_NULL);
 417     } else {
 418       return java_lang_String::as_symbol_or_null(type_str);
 419     }
 420   } else {
 421     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);
 422   }
 423 }
 424 
 425 static const char OBJ_SIG[] = "Ljava/lang/Object;";
 426 enum { OBJ_SIG_LEN = 18 };
 427 
 428 bool MethodHandles::is_basic_type_signature(Symbol* sig) {
 429   assert(vmSymbols::object_signature()->utf8_length() == (int)OBJ_SIG_LEN, "");
 430   assert(vmSymbols::object_signature()->equals(OBJ_SIG), "");
 431   const int len = sig->utf8_length();
 432   for (int i = 0; i < len; i++) {
 433     switch (sig->byte_at(i)) {
 434     case 'L':
 435       // only java/lang/Object is valid here
 436       if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)
 437         return false;
 438       i += OBJ_SIG_LEN-1;  //-1 because of i++ in loop
 439       continue;
 440     case '(': case ')': case 'V':
 441     case 'I': case 'J': case 'F': case 'D':
 442       continue;
 443     //case '[':
 444     //case 'Z': case 'B': case 'C': case 'S':
 445     default:
 446       return false;
 447     }
 448   }
 449   return true;
 450 }
 451 
 452 Symbol* MethodHandles::lookup_basic_type_signature(Symbol* sig, bool keep_last_arg, TRAPS) {
 453   Symbol* bsig = NULL;
 454   if (sig == NULL) {
 455     return sig;
 456   } else if (is_basic_type_signature(sig)) {
 457     sig->increment_refcount();
 458     return sig;  // that was easy
 459   } else if (sig->byte_at(0) != '(') {
 460     BasicType bt = char2type(sig->byte_at(0));
 461     if (is_subword_type(bt)) {
 462       bsig = vmSymbols::int_signature();
 463     } else {
 464       assert(bt == T_OBJECT || bt == T_ARRAY, "is_basic_type_signature was false");
 465       bsig = vmSymbols::object_signature();
 466     }
 467   } else {
 468     ResourceMark rm;
 469     stringStream buffer(128);
 470     buffer.put('(');
 471     int arg_pos = 0, keep_arg_pos = -1;
 472     if (keep_last_arg)
 473       keep_arg_pos = ArgumentCount(sig).size() - 1;
 474     for (SignatureStream ss(sig); !ss.is_done(); ss.next()) {
 475       BasicType bt = ss.type();
 476       size_t this_arg_pos = buffer.size();
 477       if (ss.at_return_type()) {
 478         buffer.put(')');
 479       }
 480       if (arg_pos == keep_arg_pos) {
 481         buffer.write((char*) ss.raw_bytes(),
 482                      (int)   ss.raw_length());
 483       } else if (bt == T_OBJECT || bt == T_ARRAY) {
 484         buffer.write(OBJ_SIG, OBJ_SIG_LEN);
 485       } else {
 486         if (is_subword_type(bt))
 487           bt = T_INT;
 488         buffer.put(type2char(bt));
 489       }
 490       arg_pos++;
 491     }
 492     const char* sigstr =       buffer.base();
 493     int         siglen = (int) buffer.size();
 494     bsig = SymbolTable::new_symbol(sigstr, siglen, THREAD);
 495   }
 496   assert(is_basic_type_signature(bsig) ||
 497          // detune assert in case the injected argument is not a basic type:
 498          keep_last_arg, "");
 499   return bsig;
 500 }
 501 
 502 void MethodHandles::print_as_basic_type_signature_on(outputStream* st,
 503                                                      Symbol* sig,
 504                                                      bool keep_arrays,
 505                                                      bool keep_basic_names) {
 506   st = st ? st : tty;
 507   int len  = sig->utf8_length();
 508   int array = 0;
 509   bool prev_type = false;
 510   for (int i = 0; i < len; i++) {
 511     char ch = sig->byte_at(i);
 512     switch (ch) {
 513     case '(': case ')':
 514       prev_type = false;
 515       st->put(ch);
 516       continue;
 517     case '[':
 518       if (!keep_basic_names && keep_arrays)
 519         st->put(ch);
 520       array++;
 521       continue;
 522     case 'L':
 523       {
 524         if (prev_type)  st->put(',');
 525         int start = i+1, slash = start;
 526         while (++i < len && (ch = sig->byte_at(i)) != ';') {
 527           if (ch == '/' || ch == '.' || ch == '$')  slash = i+1;
 528         }
 529         if (slash < i)  start = slash;
 530         if (!keep_basic_names) {
 531           st->put('L');
 532         } else {
 533           for (int j = start; j < i; j++)
 534             st->put(sig->byte_at(j));
 535           prev_type = true;
 536         }
 537         break;
 538       }
 539     default:
 540       {
 541         if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {
 542           ch = '[';
 543           array = 0;
 544         }
 545         if (prev_type)  st->put(',');
 546         const char* n = NULL;
 547         if (keep_basic_names)
 548           n = type2name(char2type(ch));
 549         if (n == NULL) {
 550           // unknown letter, or we don't want to know its name
 551           st->put(ch);
 552         } else {
 553           st->print(n);
 554           prev_type = true;
 555         }
 556         break;
 557       }
 558     }
 559     // Switch break goes here to take care of array suffix:
 560     if (prev_type) {
 561       while (array > 0) {
 562         st->print("[]");
 563         --array;
 564       }
 565     }
 566     array = 0;
 567   }
 568 }
 569 
 570 
 571 
 572 static oop object_java_mirror() {
 573   return SystemDictionary::Object_klass()->java_mirror();
 574 }
 575 
 576 static oop field_name_or_null(Symbol* s) {
 577   if (s == NULL)  return NULL;
 578   return StringTable::lookup(s);
 579 }
 580 
 581 static oop field_signature_type_or_null(Symbol* s) {
 582   if (s == NULL)  return NULL;
 583   BasicType bt = FieldType::basic_type(s);
 584   if (is_java_primitive(bt)) {
 585     assert(s->utf8_length() == 1, "");
 586     return java_lang_Class::primitive_mirror(bt);
 587   }
 588   // Here are some more short cuts for common types.
 589   // They are optional, since reference types can be resolved lazily.
 590   if (bt == T_OBJECT) {
 591     if (s == vmSymbols::object_signature()) {
 592       return object_java_mirror();
 593     } else if (s == vmSymbols::class_signature()) {
 594       return SystemDictionary::Class_klass()->java_mirror();
 595     } else if (s == vmSymbols::string_signature()) {
 596       return SystemDictionary::String_klass()->java_mirror();
 597     }
 598   }
 599   return NULL;
 600 }
 601 
 602 
 603 // An unresolved member name is a mere symbolic reference.
 604 // Resolving it plants a vmtarget/vmindex in it,
 605 // which refers directly to JVM internals.
 606 Handle MethodHandles::resolve_MemberName(Handle mname, TRAPS) {
 607   Handle empty;
 608   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
 609 
 610   if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {
 611     // Already resolved.
 612     DEBUG_ONLY(int vmindex = java_lang_invoke_MemberName::vmindex(mname()));
 613     assert(vmindex >= Method::nonvirtual_vtable_index, "");
 614     return mname;
 615   }
 616 
 617   Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));
 618   Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));
 619   Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));
 620   int    flags    =       java_lang_invoke_MemberName::flags(mname());
 621   int    ref_kind =       (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
 622   if (!ref_kind_is_valid(ref_kind)) {
 623     THROW_MSG_(vmSymbols::java_lang_InternalError(), "obsolete MemberName format", empty);
 624   }
 625 
 626   DEBUG_ONLY(int old_vmindex);
 627   assert((old_vmindex = java_lang_invoke_MemberName::vmindex(mname())) == 0, "clean input");
 628 
 629   if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {
 630     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve", empty);
 631   }
 632 
 633   instanceKlassHandle defc;
 634   {
 635     Klass* defc_klass = java_lang_Class::as_Klass(defc_oop());
 636     if (defc_klass == NULL)  return empty;  // a primitive; no resolution possible
 637     if (!defc_klass->oop_is_instance()) {
 638       if (!defc_klass->oop_is_array())  return empty;
 639       defc_klass = SystemDictionary::Object_klass();
 640     }
 641     defc = instanceKlassHandle(THREAD, defc_klass);
 642   }
 643   if (defc.is_null()) {
 644     THROW_MSG_(vmSymbols::java_lang_InternalError(), "primitive class", empty);
 645   }
 646   defc->link_class(CHECK_(empty));  // possible safepoint
 647 
 648   // convert the external string name to an internal symbol
 649   TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());
 650   if (name == NULL)  return empty;  // no such name
 651   if (name == vmSymbols::class_initializer_name())
 652     return empty; // illegal name
 653 
 654   vmIntrinsics::ID mh_invoke_id = vmIntrinsics::_none;
 655   if ((flags & ALL_KINDS) == IS_METHOD &&
 656       (defc() == SystemDictionary::MethodHandle_klass()) &&
 657       (ref_kind == JVM_REF_invokeVirtual ||
 658        ref_kind == JVM_REF_invokeSpecial ||
 659        // static invocation mode is required for _linkToVirtual, etc.:
 660        ref_kind == JVM_REF_invokeStatic)) {
 661     vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
 662     if (iid != vmIntrinsics::_none &&
 663         ((ref_kind == JVM_REF_invokeStatic) == is_signature_polymorphic_static(iid))) {
 664       // Virtual methods invoke and invokeExact, plus internal invokers like _invokeBasic.
 665       // For a static reference it could an internal linkage routine like _linkToVirtual, etc.
 666       mh_invoke_id = iid;
 667     }
 668   }
 669 
 670   // convert the external string or reflective type to an internal signature
 671   TempNewSymbol type = lookup_signature(type_str(), (mh_invoke_id != vmIntrinsics::_none), CHECK_(empty));
 672   if (type == NULL)  return empty;  // no such signature exists in the VM
 673 
 674   // Time to do the lookup.
 675   switch (flags & ALL_KINDS) {
 676   case IS_METHOD:
 677     {
 678       CallInfo result;
 679       {
 680         assert(!HAS_PENDING_EXCEPTION, "");
 681         if (ref_kind == JVM_REF_invokeStatic) {
 682           LinkResolver::resolve_static_call(result,
 683                         defc, name, type, KlassHandle(), false, false, THREAD);
 684         } else if (ref_kind == JVM_REF_invokeInterface) {
 685           LinkResolver::resolve_interface_call(result, Handle(), defc,
 686                         defc, name, type, KlassHandle(), false, false, THREAD);
 687         } else if (mh_invoke_id != vmIntrinsics::_none) {
 688           assert(!is_signature_polymorphic_static(mh_invoke_id), "");
 689           LinkResolver::resolve_handle_call(result,
 690                         defc, name, type, KlassHandle(), THREAD);
 691         } else if (ref_kind == JVM_REF_invokeSpecial) {
 692           LinkResolver::resolve_special_call(result,
 693                         defc, name, type, KlassHandle(), false, THREAD);
 694         } else if (ref_kind == JVM_REF_invokeVirtual) {
 695           LinkResolver::resolve_virtual_call(result, Handle(), defc,
 696                         defc, name, type, KlassHandle(), false, false, THREAD);
 697         } else {
 698           assert(false, err_msg("ref_kind=%d", ref_kind));
 699         }
 700         if (HAS_PENDING_EXCEPTION) {
 701           return empty;
 702         }
 703       }
 704       return init_method_MemberName(mname, result, THREAD);
 705     }
 706   case IS_CONSTRUCTOR:
 707     {
 708       CallInfo result;
 709       {
 710         assert(!HAS_PENDING_EXCEPTION, "");
 711         if (name == vmSymbols::object_initializer_name()) {
 712           LinkResolver::resolve_special_call(result,
 713                         defc, name, type, KlassHandle(), false, THREAD);
 714         } else {
 715           break;                // will throw after end of switch
 716         }
 717         if (HAS_PENDING_EXCEPTION) {
 718           return empty;
 719         }
 720       }
 721       assert(result.is_statically_bound(), "");
 722       return init_method_MemberName(mname, result, THREAD);
 723     }
 724   case IS_FIELD:
 725     {
 726       // This is taken from LinkResolver::resolve_field, sans access checks.
 727       fieldDescriptor fd; // find_field initializes fd if found
 728       KlassHandle sel_klass(THREAD, InstanceKlass::cast(defc())->find_field(name, type, &fd));
 729       // check if field exists; i.e., if a klass containing the field def has been selected
 730       if (sel_klass.is_null())  return empty;  // should not happen
 731       oop type = field_signature_type_or_null(fd.signature());
 732       oop name = field_name_or_null(fd.name());
 733       bool is_setter = (ref_kind_is_valid(ref_kind) && ref_kind_is_setter(ref_kind));
 734       mname = Handle(THREAD,
 735                      init_field_MemberName(mname, sel_klass,
 736                                            fd.access_flags(), type, name, fd.offset(), is_setter));
 737       return mname;
 738     }
 739   default:
 740     THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
 741   }
 742 
 743   return empty;
 744 }
 745 
 746 // Conversely, a member name which is only initialized from JVM internals
 747 // may have null defc, name, and type fields.
 748 // Resolving it plants a vmtarget/vmindex in it,
 749 // which refers directly to JVM internals.
 750 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
 751   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
 752   Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
 753   int vmindex  = java_lang_invoke_MemberName::vmindex(mname());
 754   if (vmtarget == NULL) {
 755     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
 756   }
 757 
 758   bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);
 759   bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);
 760   bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);
 761   int flags      = java_lang_invoke_MemberName::flags(mname());
 762 
 763   if (suppress != 0) {
 764     if (suppress & _suppress_defc)  have_defc = true;
 765     if (suppress & _suppress_name)  have_name = true;
 766     if (suppress & _suppress_type)  have_type = true;
 767   }
 768 
 769   if (have_defc && have_name && have_type)  return;  // nothing needed
 770 
 771   switch (flags & ALL_KINDS) {
 772   case IS_METHOD:
 773   case IS_CONSTRUCTOR:
 774     {
 775       assert(vmtarget->is_method(), "method or constructor vmtarget is Method*");
 776       methodHandle m(THREAD, (Method*)vmtarget);
 777       DEBUG_ONLY(vmtarget = NULL);  // safety
 778       if (m.is_null())  break;
 779       if (!have_defc) {
 780         InstanceKlass* defc = m->method_holder();
 781         java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
 782       }
 783       if (!have_name) {
 784         //not java_lang_String::create_from_symbol; let's intern member names
 785         Handle name = StringTable::intern(m->name(), CHECK);
 786         java_lang_invoke_MemberName::set_name(mname(), name());
 787       }
 788       if (!have_type) {
 789         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
 790         java_lang_invoke_MemberName::set_type(mname(), type());
 791       }
 792       return;
 793     }
 794   case IS_FIELD:
 795     {
 796       // This is taken from LinkResolver::resolve_field, sans access checks.
 797       assert(vmtarget->is_klass(), "field vmtarget is Klass*");
 798       if (!((Klass*) vmtarget)->oop_is_instance())  break;
 799       instanceKlassHandle defc(THREAD, (Klass*) vmtarget);
 800       DEBUG_ONLY(vmtarget = NULL);  // safety
 801       bool is_static = ((flags & JVM_ACC_STATIC) != 0);
 802       fieldDescriptor fd; // find_field initializes fd if found
 803       if (!defc->find_field_from_offset(vmindex, is_static, &fd))
 804         break;                  // cannot expand
 805       if (!have_defc) {
 806         java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
 807       }
 808       if (!have_name) {
 809         //not java_lang_String::create_from_symbol; let's intern member names
 810         Handle name = StringTable::intern(fd.name(), CHECK);
 811         java_lang_invoke_MemberName::set_name(mname(), name());
 812       }
 813       if (!have_type) {
 814         // If it is a primitive field type, don't mess with short strings like "I".
 815         Handle type = field_signature_type_or_null(fd.signature());
 816         if (type.is_null()) {
 817           java_lang_String::create_from_symbol(fd.signature(), CHECK);
 818         }
 819         java_lang_invoke_MemberName::set_type(mname(), type());
 820       }
 821       return;
 822     }
 823   }
 824   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 825 }
 826 
 827 int MethodHandles::find_MemberNames(KlassHandle k,
 828                                     Symbol* name, Symbol* sig,
 829                                     int mflags, KlassHandle caller,
 830                                     int skip, objArrayHandle results) {
 831   // %%% take caller into account!
 832 
 833   Thread* thread = Thread::current();
 834 
 835   if (k.is_null() || !k->oop_is_instance())  return -1;
 836 
 837   int rfill = 0, rlimit = results->length(), rskip = skip;
 838   // overflow measurement:
 839   int overflow = 0, overflow_limit = MAX2(1000, rlimit);
 840 
 841   int match_flags = mflags;
 842   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
 843   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);
 844   bool local_only = !(search_superc | search_intfc);
 845   bool classes_only = false;
 846 
 847   if (name != NULL) {
 848     if (name->utf8_length() == 0)  return 0; // a match is not possible
 849   }
 850   if (sig != NULL) {
 851     if (sig->utf8_length() == 0)  return 0; // a match is not possible
 852     if (sig->byte_at(0) == '(')
 853       match_flags &= ~(IS_FIELD | IS_TYPE);
 854     else
 855       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
 856   }
 857 
 858   if ((match_flags & IS_TYPE) != 0) {
 859     // NYI, and Core Reflection works quite well for this query
 860   }
 861 
 862   if ((match_flags & IS_FIELD) != 0) {
 863     for (FieldStream st(k(), local_only, !search_intfc); !st.eos(); st.next()) {
 864       if (name != NULL && st.name() != name)
 865           continue;
 866       if (sig != NULL && st.signature() != sig)
 867         continue;
 868       // passed the filters
 869       if (rskip > 0) {
 870         --rskip;
 871       } else if (rfill < rlimit) {
 872         Handle result(thread, results->obj_at(rfill++));
 873         if (!java_lang_invoke_MemberName::is_instance(result()))
 874           return -99;  // caller bug!
 875         oop type = field_signature_type_or_null(st.signature());
 876         oop name = field_name_or_null(st.name());
 877         oop saved = MethodHandles::init_field_MemberName(result, st.klass(),
 878                                                          st.access_flags(), type, name,
 879                                                          st.offset());
 880         if (saved != result())
 881           results->obj_at_put(rfill-1, saved);  // show saved instance to user
 882       } else if (++overflow >= overflow_limit) {
 883         match_flags = 0; break; // got tired of looking at overflow
 884       }
 885     }
 886   }
 887 
 888   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
 889     // watch out for these guys:
 890     Symbol* init_name   = vmSymbols::object_initializer_name();
 891     Symbol* clinit_name = vmSymbols::class_initializer_name();
 892     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>
 893     bool negate_name_test = false;
 894     // fix name so that it captures the intention of IS_CONSTRUCTOR
 895     if (!(match_flags & IS_METHOD)) {
 896       // constructors only
 897       if (name == NULL) {
 898         name = init_name;
 899       } else if (name != init_name) {
 900         return 0;               // no constructors of this method name
 901       }
 902     } else if (!(match_flags & IS_CONSTRUCTOR)) {
 903       // methods only
 904       if (name == NULL) {
 905         name = init_name;
 906         negate_name_test = true; // if we see the name, we *omit* the entry
 907       } else if (name == init_name) {
 908         return 0;               // no methods of this constructor name
 909       }
 910     } else {
 911       // caller will accept either sort; no need to adjust name
 912     }
 913     for (MethodStream st(k(), local_only, !search_intfc); !st.eos(); st.next()) {
 914       Method* m = st.method();
 915       Symbol* m_name = m->name();
 916       if (m_name == clinit_name)
 917         continue;
 918       if (name != NULL && ((m_name != name) ^ negate_name_test))
 919           continue;
 920       if (sig != NULL && m->signature() != sig)
 921         continue;
 922       // passed the filters
 923       if (rskip > 0) {
 924         --rskip;
 925       } else if (rfill < rlimit) {
 926         Handle result(thread, results->obj_at(rfill++));
 927         if (!java_lang_invoke_MemberName::is_instance(result()))
 928           return -99;  // caller bug!
 929         oop saved = MethodHandles::init_method_MemberName(result, m, true, NULL);
 930         if (saved != result())
 931           results->obj_at_put(rfill-1, saved);  // show saved instance to user
 932       } else if (++overflow >= overflow_limit) {
 933         match_flags = 0; break; // got tired of looking at overflow
 934       }
 935     }
 936   }
 937 
 938   // return number of elements we at leasted wanted to initialize
 939   return rfill + overflow;
 940 }
 941 
 942 //------------------------------------------------------------------------------
 943 // MemberNameTable
 944 //
 945 
 946 MemberNameTable::MemberNameTable(int methods_cnt)
 947                   : GrowableArray<jweak>(methods_cnt, true) {
 948   assert_locked_or_safepoint(MemberNameTable_lock);
 949 }
 950 
 951 MemberNameTable::~MemberNameTable() {
 952   assert_locked_or_safepoint(MemberNameTable_lock);
 953   int len = this->length();
 954 
 955   for (int idx = 0; idx < len; idx++) {
 956     jweak ref = this->at(idx);
 957     JNIHandles::destroy_weak_global(ref);
 958   }
 959 }
 960 
 961 void MemberNameTable::add_member_name(int index, jweak mem_name_wref) {
 962   assert_locked_or_safepoint(MemberNameTable_lock);
 963   this->at_put_grow(index, mem_name_wref);
 964 }
 965 
 966 // Return a member name oop or NULL.
 967 oop MemberNameTable::get_member_name(int index) {
 968   assert_locked_or_safepoint(MemberNameTable_lock);
 969 
 970   jweak ref = this->at(index);
 971   oop mem_name = JNIHandles::resolve(ref);
 972   return mem_name;
 973 }
 974 
 975 #if INCLUDE_JVMTI
 976 oop MemberNameTable::find_member_name_by_method(Method* old_method) {
 977   assert_locked_or_safepoint(MemberNameTable_lock);
 978   oop found = NULL;
 979   int len = this->length();
 980 
 981   for (int idx = 0; idx < len; idx++) {
 982     oop mem_name = JNIHandles::resolve(this->at(idx));
 983     if (mem_name == NULL) {
 984       continue;
 985     }
 986     Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name);
 987     if (method == old_method) {
 988       found = mem_name;
 989       break;
 990     }
 991   }
 992   return found;
 993 }
 994 
 995 // It is called at safepoint only
 996 void MemberNameTable::adjust_method_entries(Method** old_methods, Method** new_methods,
 997                                             int methods_length, bool *trace_name_printed) {
 998   assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
 999   // search the MemberNameTable for uses of either obsolete or EMCP methods
1000   for (int j = 0; j < methods_length; j++) {
1001     Method* old_method = old_methods[j];
1002     Method* new_method = new_methods[j];
1003     oop mem_name = find_member_name_by_method(old_method);
1004     if (mem_name != NULL) {
1005       java_lang_invoke_MemberName::adjust_vmtarget(mem_name, new_method);
1006 
1007       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
1008         if (!(*trace_name_printed)) {
1009           // RC_TRACE_MESG macro has an embedded ResourceMark
1010           RC_TRACE_MESG(("adjust: name=%s",
1011                          old_method->method_holder()->external_name()));
1012           *trace_name_printed = true;
1013         }
1014         // RC_TRACE macro has an embedded ResourceMark
1015         RC_TRACE(0x00400000, ("MemberName method update: %s(%s)",
1016                               new_method->name()->as_C_string(),
1017                               new_method->signature()->as_C_string()));
1018       }
1019     }
1020   }
1021 }
1022 #endif // INCLUDE_JVMTI
1023 
1024 //
1025 // Here are the native methods in java.lang.invoke.MethodHandleNatives
1026 // They are the private interface between this JVM and the HotSpot-specific
1027 // Java code that implements JSR 292 method handles.
1028 //
1029 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way
1030 // that intrinsic (non-JNI) native methods are defined in HotSpot.
1031 //
1032 
1033 JVM_ENTRY(jint, MHN_getConstant(JNIEnv *env, jobject igcls, jint which)) {
1034   switch (which) {
1035   case MethodHandles::GC_COUNT_GWT:
1036 #ifdef COMPILER2
1037     return true;
1038 #else
1039     return false;
1040 #endif
1041   }
1042   return 0;
1043 }
1044 JVM_END
1045 
1046 #ifndef PRODUCT
1047 #define EACH_NAMED_CON(template, requirement) \
1048     template(MethodHandles,GC_COUNT_GWT) \
1049     template(java_lang_invoke_MemberName,MN_IS_METHOD) \
1050     template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \
1051     template(java_lang_invoke_MemberName,MN_IS_FIELD) \
1052     template(java_lang_invoke_MemberName,MN_IS_TYPE) \
1053     template(java_lang_invoke_MemberName,MN_CALLER_SENSITIVE) \
1054     template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \
1055     template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \
1056     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_SHIFT) \
1057     template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_MASK) \
1058     template(MethodHandles,GC_LAMBDA_SUPPORT) \
1059     /*end*/
1060 
1061 #define IGNORE_REQ(req_expr) /* req_expr */
1062 #define ONE_PLUS(scope,value) 1+
1063 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS, IGNORE_REQ) 0;
1064 #define VALUE_COMMA(scope,value) scope::value,
1065 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA, IGNORE_REQ) 0 };
1066 #define STRING_NULL(scope,value) #value "\0"
1067 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL, IGNORE_REQ) };
1068 
1069 static bool advertise_con_value(int which) {
1070   if (which < 0)  return false;
1071   bool ok = true;
1072   int count = 0;
1073 #define INC_COUNT(scope,value) \
1074   ++count;
1075 #define CHECK_REQ(req_expr) \
1076   if (which < count)  return ok; \
1077   ok = (req_expr);
1078   EACH_NAMED_CON(INC_COUNT, CHECK_REQ);
1079 #undef INC_COUNT
1080 #undef CHECK_REQ
1081   assert(count == con_value_count, "");
1082   if (which < count)  return ok;
1083   return false;
1084 }
1085 
1086 #undef ONE_PLUS
1087 #undef VALUE_COMMA
1088 #undef STRING_NULL
1089 #undef EACH_NAMED_CON
1090 #endif // PRODUCT
1091 
1092 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
1093 #ifndef PRODUCT
1094   if (advertise_con_value(which)) {
1095     assert(which >= 0 && which < con_value_count, "");
1096     int con = con_values[which];
1097     objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));
1098     if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
1099       const char* str = &con_names[0];
1100       for (int i = 0; i < which; i++)
1101         str += strlen(str) + 1;   // skip name and null
1102       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);  // possible safepoint
1103       box->obj_at_put(0, name);
1104     }
1105     return con;
1106   }
1107 #endif
1108   return 0;
1109 }
1110 JVM_END
1111 
1112 // void init(MemberName self, AccessibleObject ref)
1113 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
1114   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1115   if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
1116   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1117   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
1118   MethodHandles::init_MemberName(mname, target);
1119 }
1120 JVM_END
1121 
1122 // void expand(MemberName self)
1123 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1124   if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1125   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1126   MethodHandles::expand_MemberName(mname, 0, CHECK);
1127 }
1128 JVM_END
1129 
1130 // void resolve(MemberName self, Class<?> caller)
1131 JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
1132   if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }
1133   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1134 
1135   // The trusted Java code that calls this method should already have performed
1136   // access checks on behalf of the given caller.  But, we can verify this.
1137   if (VerifyMethodHandles && caller_jh != NULL &&
1138       java_lang_invoke_MemberName::clazz(mname()) != NULL) {
1139     Klass* reference_klass = java_lang_Class::as_Klass(java_lang_invoke_MemberName::clazz(mname()));
1140     if (reference_klass != NULL && reference_klass->oop_is_objArray()) {
1141       reference_klass = ObjArrayKlass::cast(reference_klass)->bottom_klass();
1142     }
1143 
1144     // Reflection::verify_class_access can only handle instance classes.
1145     if (reference_klass != NULL && reference_klass->oop_is_instance()) {
1146       // Emulate LinkResolver::check_klass_accessability.
1147       Klass* caller = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
1148       if (!Reflection::verify_class_access(caller,
1149                                            reference_klass,
1150                                            true)) {
1151         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), reference_klass->external_name());
1152       }
1153     }
1154   }
1155 
1156   Handle resolved = MethodHandles::resolve_MemberName(mname, CHECK_NULL);
1157   if (resolved.is_null()) {
1158     int flags = java_lang_invoke_MemberName::flags(mname());
1159     int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
1160     if (!MethodHandles::ref_kind_is_valid(ref_kind)) {
1161       THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "obsolete MemberName format");
1162     }
1163     if ((flags & ALL_KINDS) == IS_FIELD) {
1164       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), "field resolution failed");
1165     } else if ((flags & ALL_KINDS) == IS_METHOD ||
1166                (flags & ALL_KINDS) == IS_CONSTRUCTOR) {
1167       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchFieldError(), "method resolution failed");
1168     } else {
1169       THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "resolution failed");
1170     }
1171   }
1172 
1173   return JNIHandles::make_local(THREAD, resolved());
1174 }
1175 JVM_END
1176 
1177 static jlong find_member_field_offset(oop mname, bool must_be_static, TRAPS) {
1178   if (mname == NULL ||
1179       java_lang_invoke_MemberName::vmtarget(mname) == NULL) {
1180     THROW_MSG_0(vmSymbols::java_lang_InternalError(), "mname not resolved");
1181   } else {
1182     int flags = java_lang_invoke_MemberName::flags(mname);
1183     if ((flags & IS_FIELD) != 0 &&
1184         (must_be_static
1185          ? (flags & JVM_ACC_STATIC) != 0
1186          : (flags & JVM_ACC_STATIC) == 0)) {
1187       int vmindex = java_lang_invoke_MemberName::vmindex(mname);
1188       return (jlong) vmindex;
1189     }
1190   }
1191   const char* msg = (must_be_static ? "static field required" : "non-static field required");
1192   THROW_MSG_0(vmSymbols::java_lang_InternalError(), msg);
1193   return 0;
1194 }
1195 
1196 JVM_ENTRY(jlong, MHN_objectFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1197   return find_member_field_offset(JNIHandles::resolve(mname_jh), false, THREAD);
1198 }
1199 JVM_END
1200 
1201 JVM_ENTRY(jlong, MHN_staticFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1202   return find_member_field_offset(JNIHandles::resolve(mname_jh), true, THREAD);
1203 }
1204 JVM_END
1205 
1206 JVM_ENTRY(jobject, MHN_staticFieldBase(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1207   // use the other function to perform sanity checks:
1208   jlong ignore = find_member_field_offset(JNIHandles::resolve(mname_jh), true, CHECK_NULL);
1209   oop clazz = java_lang_invoke_MemberName::clazz(JNIHandles::resolve_non_null(mname_jh));
1210   return JNIHandles::make_local(THREAD, clazz);
1211 }
1212 JVM_END
1213 
1214 JVM_ENTRY(jobject, MHN_getMemberVMInfo(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1215   if (mname_jh == NULL)  return NULL;
1216   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1217   intptr_t vmindex  = java_lang_invoke_MemberName::vmindex(mname());
1218   Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
1219   objArrayHandle result = oopFactory::new_objArray(SystemDictionary::Object_klass(), 2, CHECK_NULL);
1220   jvalue vmindex_value; vmindex_value.j = (long)vmindex;
1221   oop x = java_lang_boxing_object::create(T_LONG, &vmindex_value, CHECK_NULL);
1222   result->obj_at_put(0, x);
1223   x = NULL;
1224   if (vmtarget == NULL) {
1225     x = NULL;
1226   } else if (vmtarget->is_klass()) {
1227     x = ((Klass*) vmtarget)->java_mirror();
1228   } else if (vmtarget->is_method()) {
1229     Handle mname2 = MethodHandles::new_MemberName(CHECK_NULL);
1230     x = MethodHandles::init_method_MemberName(mname2, (Method*)vmtarget, false, NULL);
1231   }
1232   result->obj_at_put(1, x);
1233   return JNIHandles::make_local(env, result());
1234 }
1235 JVM_END
1236 
1237 
1238 
1239 //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
1240 //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
1241 JVM_ENTRY(jint, MHN_getMembers(JNIEnv *env, jobject igcls,
1242                                jclass clazz_jh, jstring name_jh, jstring sig_jh,
1243                                int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
1244   if (clazz_jh == NULL || results_jh == NULL)  return -1;
1245   KlassHandle k(THREAD, java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz_jh)));
1246 
1247   objArrayHandle results(THREAD, (objArrayOop) JNIHandles::resolve(results_jh));
1248   if (results.is_null() || !results->is_objArray())  return -1;
1249 
1250   TempNewSymbol name = NULL;
1251   TempNewSymbol sig = NULL;
1252   if (name_jh != NULL) {
1253     name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
1254     if (name == NULL)  return 0; // a match is not possible
1255   }
1256   if (sig_jh != NULL) {
1257     sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
1258     if (sig == NULL)  return 0; // a match is not possible
1259   }
1260 
1261   KlassHandle caller;
1262   if (caller_jh != NULL) {
1263     oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
1264     if (!java_lang_Class::is_instance(caller_oop))  return -1;
1265     caller = KlassHandle(THREAD, java_lang_Class::as_Klass(caller_oop));
1266   }
1267 
1268   if (name != NULL && sig != NULL && results.not_null()) {
1269     // try a direct resolve
1270     // %%% TO DO
1271   }
1272 
1273   int res = MethodHandles::find_MemberNames(k, name, sig, mflags,
1274                                             caller, skip, results);
1275   // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
1276   return res;
1277 }
1278 JVM_END
1279 
1280 JVM_ENTRY(void, MHN_setCallSiteTargetNormal(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1281   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1282   Handle target   (THREAD, JNIHandles::resolve(target_jh));
1283   {
1284     // Walk all nmethods depending on this call site.
1285     MutexLocker mu(Compile_lock, thread);
1286     Universe::flush_dependents_on(call_site, target);
1287     java_lang_invoke_CallSite::set_target(call_site(), target());
1288   }
1289 }
1290 JVM_END
1291 
1292 JVM_ENTRY(void, MHN_setCallSiteTargetVolatile(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1293   Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1294   Handle target   (THREAD, JNIHandles::resolve(target_jh));
1295   {
1296     // Walk all nmethods depending on this call site.
1297     MutexLocker mu(Compile_lock, thread);
1298     Universe::flush_dependents_on(call_site, target);
1299     java_lang_invoke_CallSite::set_target_volatile(call_site(), target());
1300   }
1301 }
1302 JVM_END
1303 
1304 /**
1305  * Throws a java/lang/UnsupportedOperationException unconditionally.
1306  * This is required by the specification of MethodHandle.invoke if
1307  * invoked directly.
1308  */
1309 JVM_ENTRY(jobject, MH_invoke_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1310   THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invoke cannot be invoked reflectively");
1311   return NULL;
1312 }
1313 JVM_END
1314 
1315 /**
1316  * Throws a java/lang/UnsupportedOperationException unconditionally.
1317  * This is required by the specification of MethodHandle.invokeExact if
1318  * invoked directly.
1319  */
1320 JVM_ENTRY(jobject, MH_invokeExact_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1321   THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invokeExact cannot be invoked reflectively");
1322   return NULL;
1323 }
1324 JVM_END
1325 
1326 /// JVM_RegisterMethodHandleMethods
1327 
1328 #undef CS  // Solaris builds complain
1329 
1330 #define LANG "Ljava/lang/"
1331 #define JLINV "Ljava/lang/invoke/"
1332 
1333 #define OBJ   LANG"Object;"
1334 #define CLS   LANG"Class;"
1335 #define STRG  LANG"String;"
1336 #define CS    JLINV"CallSite;"
1337 #define MT    JLINV"MethodType;"
1338 #define MH    JLINV"MethodHandle;"
1339 #define MEM   JLINV"MemberName;"
1340 
1341 #define CC (char*)  /*cast a literal from (const char*)*/
1342 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1343 
1344 // These are the native methods on java.lang.invoke.MethodHandleNatives.
1345 static JNINativeMethod MHN_methods[] = {
1346   {CC"init",                      CC"("MEM""OBJ")V",                     FN_PTR(MHN_init_Mem)},
1347   {CC"expand",                    CC"("MEM")V",                          FN_PTR(MHN_expand_Mem)},
1348   {CC"resolve",                   CC"("MEM""CLS")"MEM,                   FN_PTR(MHN_resolve_Mem)},
1349   {CC"getConstant",               CC"(I)I",                              FN_PTR(MHN_getConstant)},
1350   //  static native int getNamedCon(int which, Object[] name)
1351   {CC"getNamedCon",               CC"(I["OBJ")I",                        FN_PTR(MHN_getNamedCon)},
1352   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
1353   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
1354   {CC"getMembers",                CC"("CLS""STRG""STRG"I"CLS"I["MEM")I", FN_PTR(MHN_getMembers)},
1355   {CC"objectFieldOffset",         CC"("MEM")J",                          FN_PTR(MHN_objectFieldOffset)},
1356   {CC"setCallSiteTargetNormal",   CC"("CS""MH")V",                       FN_PTR(MHN_setCallSiteTargetNormal)},
1357   {CC"setCallSiteTargetVolatile", CC"("CS""MH")V",                       FN_PTR(MHN_setCallSiteTargetVolatile)},
1358   {CC"staticFieldOffset",         CC"("MEM")J",                          FN_PTR(MHN_staticFieldOffset)},
1359   {CC"staticFieldBase",           CC"("MEM")"OBJ,                        FN_PTR(MHN_staticFieldBase)},
1360   {CC"getMemberVMInfo",           CC"("MEM")"OBJ,                        FN_PTR(MHN_getMemberVMInfo)}
1361 };
1362 
1363 static JNINativeMethod MH_methods[] = {
1364   // UnsupportedOperationException throwers
1365   {CC"invoke",                    CC"(["OBJ")"OBJ,                       FN_PTR(MH_invoke_UOE)},
1366   {CC"invokeExact",               CC"(["OBJ")"OBJ,                       FN_PTR(MH_invokeExact_UOE)}
1367 };
1368 
1369 /**
1370  * Helper method to register native methods.
1371  */
1372 static bool register_natives(JNIEnv* env, jclass clazz, const JNINativeMethod* methods, jint nMethods) {
1373   int status = env->RegisterNatives(clazz, methods, nMethods);
1374   if (status != JNI_OK || env->ExceptionOccurred()) {
1375     warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
1376     env->ExceptionClear();
1377     return false;
1378   }
1379   return true;
1380 }
1381 
1382 /**
1383  * This one function is exported, used by NativeLookup.
1384  */
1385 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
1386   if (!EnableInvokeDynamic) {
1387     warning("JSR 292 is disabled in this JVM.  Use -XX:+UnlockDiagnosticVMOptions -XX:+EnableInvokeDynamic to enable.");
1388     return;  // bind nothing
1389   }
1390 
1391   assert(!MethodHandles::enabled(), "must not be enabled");
1392   bool enable_MH = true;
1393 
1394   jclass MH_class = NULL;
1395   if (SystemDictionary::MethodHandle_klass() == NULL) {
1396     enable_MH = false;
1397   } else {
1398     oop mirror = SystemDictionary::MethodHandle_klass()->java_mirror();
1399     MH_class = (jclass) JNIHandles::make_local(env, mirror);
1400   }
1401 
1402   if (enable_MH) {
1403     ThreadToNativeFromVM ttnfv(thread);
1404 
1405     if (enable_MH) {
1406       enable_MH = register_natives(env, MHN_class, MHN_methods, sizeof(MHN_methods)/sizeof(JNINativeMethod));
1407     }
1408     if (enable_MH) {
1409       enable_MH = register_natives(env, MH_class, MH_methods, sizeof(MH_methods)/sizeof(JNINativeMethod));
1410     }
1411   }
1412 
1413   if (TraceInvokeDynamic) {
1414     tty->print_cr("MethodHandle support loaded (using LambdaForms)");
1415   }
1416 
1417   if (enable_MH) {
1418     MethodHandles::generate_adapters();
1419     MethodHandles::set_enabled(true);
1420   }
1421 }
1422 JVM_END