1 /*
   2  * Copyright (c) 2008, 2010, 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 "interpreter/interpreter.hpp"
  28 #include "memory/allocation.inline.hpp"
  29 #include "memory/oopFactory.hpp"
  30 #include "prims/methodHandles.hpp"
  31 #include "runtime/javaCalls.hpp"
  32 #include "runtime/reflection.hpp"
  33 #include "runtime/signature.hpp"
  34 #include "runtime/stubRoutines.hpp"
  35 
  36 /*
  37  * JSR 292 reference implementation: method handles
  38  */
  39 
  40 bool MethodHandles::_enabled = false; // set true after successful native linkage
  41 
  42 MethodHandleEntry* MethodHandles::_entries[MethodHandles::_EK_LIMIT] = {NULL};
  43 const char*        MethodHandles::_entry_names[_EK_LIMIT+1] = {
  44   "raise_exception",
  45   "invokestatic",               // how a MH emulates invokestatic
  46   "invokespecial",              // ditto for the other invokes...
  47   "invokevirtual",
  48   "invokeinterface",
  49   "bound_ref",                  // these are for BMH...
  50   "bound_int",
  51   "bound_long",
  52   "bound_ref_direct",           // (direct versions have a direct methodOop)
  53   "bound_int_direct",
  54   "bound_long_direct",
  55 
  56   // starting at _adapter_mh_first:
  57   "adapter_retype_only",       // these are for AMH...
  58   "adapter_retype_raw",
  59   "adapter_check_cast",
  60   "adapter_prim_to_prim",
  61   "adapter_ref_to_prim",
  62   "adapter_prim_to_ref",
  63   "adapter_swap_args",
  64   "adapter_rot_args",
  65   "adapter_dup_args",
  66   "adapter_drop_args",
  67   "adapter_collect_args",
  68   "adapter_spread_args",
  69   "adapter_flyby",
  70   "adapter_ricochet",
  71 
  72   // optimized adapter types:
  73   "adapter_swap_args/1",
  74   "adapter_swap_args/2",
  75   "adapter_rot_args/1,up",
  76   "adapter_rot_args/1,down",
  77   "adapter_rot_args/2,up",
  78   "adapter_rot_args/2,down",
  79   "adapter_prim_to_prim/i2i",
  80   "adapter_prim_to_prim/l2i",
  81   "adapter_prim_to_prim/d2f",
  82   "adapter_prim_to_prim/i2l",
  83   "adapter_prim_to_prim/f2d",
  84   "adapter_ref_to_prim/unboxi",
  85   "adapter_ref_to_prim/unboxl",
  86   "adapter_spread_args/0",
  87   "adapter_spread_args/1",
  88   "adapter_spread_args/more",
  89 
  90   NULL
  91 };
  92 
  93 // Adapters.
  94 MethodHandlesAdapterBlob* MethodHandles::_adapter_code      = NULL;
  95 int                       MethodHandles::_adapter_code_size = StubRoutines::method_handles_adapters_code_size;
  96 
  97 jobject MethodHandles::_raise_exception_method;
  98 
  99 #ifdef ASSERT
 100 bool MethodHandles::spot_check_entry_names() {
 101   assert(!strcmp(entry_name(_invokestatic_mh), "invokestatic"), "");
 102   assert(!strcmp(entry_name(_bound_ref_mh), "bound_ref"), "");
 103   assert(!strcmp(entry_name(_adapter_retype_only), "adapter_retype_only"), "");
 104   assert(!strcmp(entry_name(_adapter_ricochet), "adapter_ricochet"), "");
 105   assert(!strcmp(entry_name(_adapter_opt_unboxi), "adapter_ref_to_prim/unboxi"), "");
 106   return true;
 107 }
 108 #endif
 109 
 110 
 111 //------------------------------------------------------------------------------
 112 // MethodHandles::generate_adapters
 113 //
 114 void MethodHandles::generate_adapters(TRAPS) {
 115   if (!EnableMethodHandles || SystemDictionary::MethodHandle_klass() == NULL)  return;
 116 
 117   assert(_adapter_code == NULL, "generate only once");
 118 
 119   ResourceMark rm;
 120   TraceTime timer("MethodHandles adapters generation", TraceStartupTime);
 121   _adapter_code = MethodHandlesAdapterBlob::create(_adapter_code_size);
 122   if (_adapter_code == NULL)
 123     vm_exit_out_of_memory(_adapter_code_size, "CodeCache: no room for MethodHandles adapters");
 124   CodeBuffer code(_adapter_code);
 125   MethodHandlesAdapterGenerator g(&code);
 126   g.generate(CHECK);
 127 }
 128 
 129 
 130 //------------------------------------------------------------------------------
 131 // MethodHandlesAdapterGenerator::generate
 132 //
 133 void MethodHandlesAdapterGenerator::generate(TRAPS) {
 134   // Generate generic method handle adapters.
 135   for (MethodHandles::EntryKind ek = MethodHandles::_EK_FIRST;
 136        ek < MethodHandles::_EK_LIMIT;
 137        ek = MethodHandles::EntryKind(1 + (int)ek)) {
 138     StubCodeMark mark(this, "MethodHandle", MethodHandles::entry_name(ek));
 139     MethodHandles::generate_method_handle_stub(_masm, ek, CHECK);
 140   }
 141 }
 142 
 143 
 144 void MethodHandles::set_enabled(bool z) {
 145   if (_enabled != z) {
 146     guarantee(z && EnableMethodHandles, "can only enable once, and only if -XX:+EnableMethodHandles");
 147     _enabled = z;
 148   }
 149 }
 150 
 151 // Note: A method which does not have a TRAPS argument cannot block in the GC
 152 // or throw exceptions.  Such methods are used in this file to do something quick
 153 // and local, like parse a data structure.  For speed, such methods work on plain
 154 // oops, not handles.  Trapping methods uniformly operate on handles.
 155 
 156 methodOop MethodHandles::decode_vmtarget(oop vmtarget, int vmindex, oop mtype,
 157                                          klassOop& receiver_limit_result, int& decode_flags_result) {
 158   if (vmtarget == NULL)  return NULL;
 159   assert(methodOopDesc::nonvirtual_vtable_index < 0, "encoding");
 160   if (vmindex < 0) {
 161     // this DMH performs no dispatch; it is directly bound to a methodOop
 162     // A MemberName may either be directly bound to a methodOop,
 163     // or it may use the klass/index form; both forms mean the same thing.
 164     methodOop m = decode_methodOop(methodOop(vmtarget), decode_flags_result);
 165     if ((decode_flags_result & _dmf_has_receiver) != 0
 166         && java_dyn_MethodType::is_instance(mtype)) {
 167       // Extract receiver type restriction from mtype.ptypes[0].
 168       objArrayOop ptypes = java_dyn_MethodType::ptypes(mtype);
 169       oop ptype0 = (ptypes == NULL || ptypes->length() < 1) ? oop(NULL) : ptypes->obj_at(0);
 170       if (java_lang_Class::is_instance(ptype0))
 171         receiver_limit_result = java_lang_Class::as_klassOop(ptype0);
 172     }
 173     if (vmindex == methodOopDesc::nonvirtual_vtable_index) {
 174       // this DMH can be an "invokespecial" version
 175       decode_flags_result &= ~_dmf_does_dispatch;
 176     } else {
 177       assert(vmindex == methodOopDesc::invalid_vtable_index, "random vmindex?");
 178     }
 179     return m;
 180   } else {
 181     assert(vmtarget->is_klass(), "must be class or interface");
 182     decode_flags_result |= MethodHandles::_dmf_does_dispatch;
 183     decode_flags_result |= MethodHandles::_dmf_has_receiver;
 184     receiver_limit_result = (klassOop)vmtarget;
 185     Klass* tk = Klass::cast((klassOop)vmtarget);
 186     if (tk->is_interface()) {
 187       // an itable linkage is <interface, itable index>
 188       decode_flags_result |= MethodHandles::_dmf_from_interface;
 189       return klassItable::method_for_itable_index((klassOop)vmtarget, vmindex);
 190     } else {
 191       if (!tk->oop_is_instance())
 192         tk = instanceKlass::cast(SystemDictionary::Object_klass());
 193       return ((instanceKlass*)tk)->method_at_vtable(vmindex);
 194     }
 195   }
 196 }
 197 
 198 // MemberName and DirectMethodHandle have the same linkage to the JVM internals.
 199 // (MemberName is the non-operational name used for queries and setup.)
 200 
 201 methodOop MethodHandles::decode_DirectMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
 202   oop vmtarget = sun_dyn_DirectMethodHandle::vmtarget(mh);
 203   int vmindex  = sun_dyn_DirectMethodHandle::vmindex(mh);
 204   oop mtype    = sun_dyn_DirectMethodHandle::type(mh);
 205   return decode_vmtarget(vmtarget, vmindex, mtype, receiver_limit_result, decode_flags_result);
 206 }
 207 
 208 methodOop MethodHandles::decode_BoundMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
 209   assert(sun_dyn_BoundMethodHandle::is_instance(mh), "");
 210   assert(mh->klass() != SystemDictionary::AdapterMethodHandle_klass(), "");
 211   for (oop bmh = mh;;) {
 212     // Bound MHs can be stacked to bind several arguments.
 213     oop target = java_dyn_MethodHandle::vmtarget(bmh);
 214     if (target == NULL)  return NULL;
 215     decode_flags_result |= MethodHandles::_dmf_binds_argument;
 216     klassOop tk = target->klass();
 217     if (tk == SystemDictionary::BoundMethodHandle_klass()) {
 218       bmh = target;
 219       continue;
 220     } else {
 221       if (java_dyn_MethodHandle::is_subclass(tk)) {
 222         //assert(tk == SystemDictionary::DirectMethodHandle_klass(), "end of BMH chain must be DMH");
 223         return decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
 224       } else {
 225         // Optimized case:  binding a receiver to a non-dispatched DMH
 226         // short-circuits directly to the methodOop.
 227         // (It might be another argument besides a receiver also.)
 228         assert(target->is_method(), "must be a simple method");
 229         decode_flags_result |= MethodHandles::_dmf_binds_method;
 230         methodOop m = (methodOop) target;
 231         if (!m->is_static())
 232           decode_flags_result |= MethodHandles::_dmf_has_receiver;
 233         return m;
 234       }
 235     }
 236   }
 237 }
 238 
 239 methodOop MethodHandles::decode_AdapterMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
 240   assert(mh->klass() == SystemDictionary::AdapterMethodHandle_klass(), "");
 241   for (oop amh = mh;;) {
 242     // Adapter MHs can be stacked to convert several arguments.
 243     int conv_op = adapter_conversion_op(sun_dyn_AdapterMethodHandle::conversion(amh));
 244     decode_flags_result |= (_dmf_adapter_lsb << conv_op) & _DMF_ADAPTER_MASK;
 245     oop target = java_dyn_MethodHandle::vmtarget(amh);
 246     if (target == NULL)  return NULL;
 247     klassOop tk = target->klass();
 248     if (tk == SystemDictionary::AdapterMethodHandle_klass()) {
 249       amh = target;
 250       continue;
 251     } else {
 252       // must be a BMH (which will bind some more arguments) or a DMH (for the final call)
 253       return MethodHandles::decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
 254     }
 255   }
 256 }
 257 
 258 methodOop MethodHandles::decode_MethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result) {
 259   if (mh == NULL)  return NULL;
 260   klassOop mhk = mh->klass();
 261   assert(java_dyn_MethodHandle::is_subclass(mhk), "must be a MethodHandle");
 262   if (mhk == SystemDictionary::DirectMethodHandle_klass()) {
 263     return decode_DirectMethodHandle(mh, receiver_limit_result, decode_flags_result);
 264   } else if (mhk == SystemDictionary::BoundMethodHandle_klass()) {
 265     return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
 266   } else if (mhk == SystemDictionary::AdapterMethodHandle_klass()) {
 267     return decode_AdapterMethodHandle(mh, receiver_limit_result, decode_flags_result);
 268   } else if (sun_dyn_BoundMethodHandle::is_subclass(mhk)) {
 269     // could be a JavaMethodHandle (but not an adapter MH)
 270     return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
 271   } else {
 272     assert(false, "cannot parse this MH");
 273     return NULL;              // random MH?
 274   }
 275 }
 276 
 277 methodOop MethodHandles::decode_methodOop(methodOop m, int& decode_flags_result) {
 278   assert(m->is_method(), "");
 279   if (m->is_static()) {
 280     // check that signature begins '(L' or '([' (not '(I', '()', etc.)
 281     symbolOop sig = m->signature();
 282     BasicType recv_bt = char2type(sig->byte_at(1));
 283     // Note: recv_bt might be T_ILLEGAL if byte_at(2) is ')'
 284     assert(sig->byte_at(0) == '(', "must be method sig");
 285 //     if (recv_bt == T_OBJECT || recv_bt == T_ARRAY)
 286 //       decode_flags_result |= _dmf_has_receiver;
 287   } else {
 288     // non-static method
 289     decode_flags_result |= _dmf_has_receiver;
 290     if (!m->can_be_statically_bound() && !m->is_initializer()) {
 291       decode_flags_result |= _dmf_does_dispatch;
 292       if (Klass::cast(m->method_holder())->is_interface())
 293         decode_flags_result |= _dmf_from_interface;
 294     }
 295   }
 296   return m;
 297 }
 298 
 299 
 300 // A trusted party is handing us a cookie to determine a method.
 301 // Let's boil it down to the method oop they really want.
 302 methodOop MethodHandles::decode_method(oop x, klassOop& receiver_limit_result, int& decode_flags_result) {
 303   decode_flags_result = 0;
 304   receiver_limit_result = NULL;
 305   klassOop xk = x->klass();
 306   if (xk == Universe::methodKlassObj()) {
 307     return decode_methodOop((methodOop) x, decode_flags_result);
 308   } else if (xk == SystemDictionary::MemberName_klass()) {
 309     // Note: This only works if the MemberName has already been resolved.
 310     return decode_MemberName(x, receiver_limit_result, decode_flags_result);
 311   } else if (java_dyn_MethodHandle::is_subclass(xk)) {
 312     return decode_MethodHandle(x, receiver_limit_result, decode_flags_result);
 313   } else if (xk == SystemDictionary::reflect_Method_klass()) {
 314     oop clazz  = java_lang_reflect_Method::clazz(x);
 315     int slot   = java_lang_reflect_Method::slot(x);
 316     klassOop k = java_lang_Class::as_klassOop(clazz);
 317     if (k != NULL && Klass::cast(k)->oop_is_instance())
 318       return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
 319                               decode_flags_result);
 320   } else if (xk == SystemDictionary::reflect_Constructor_klass()) {
 321     oop clazz  = java_lang_reflect_Constructor::clazz(x);
 322     int slot   = java_lang_reflect_Constructor::slot(x);
 323     klassOop k = java_lang_Class::as_klassOop(clazz);
 324     if (k != NULL && Klass::cast(k)->oop_is_instance())
 325       return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
 326                               decode_flags_result);
 327   } else {
 328     // unrecognized object
 329     assert(!x->is_method(), "already checked");
 330     assert(!sun_dyn_MemberName::is_instance(x), "already checked");
 331   }
 332   return NULL;
 333 }
 334 
 335 
 336 int MethodHandles::decode_MethodHandle_stack_pushes(oop mh) {
 337   if (mh->klass() == SystemDictionary::DirectMethodHandle_klass())
 338     return 0;                   // no push/pop
 339   int this_vmslots = java_dyn_MethodHandle::vmslots(mh);
 340   int last_vmslots = 0;
 341   oop last_mh = mh;
 342   for (;;) {
 343     oop target = java_dyn_MethodHandle::vmtarget(last_mh);
 344     if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
 345       last_vmslots = java_dyn_MethodHandle::vmslots(target);
 346       break;
 347     } else if (!java_dyn_MethodHandle::is_instance(target)) {
 348       // might be klass or method
 349       assert(target->is_method(), "must get here with a direct ref to method");
 350       last_vmslots = methodOop(target)->size_of_parameters();
 351       break;
 352     }
 353     last_mh = target;
 354   }
 355   // If I am called with fewer VM slots than my ultimate callee,
 356   // it must be that I push the additionally needed slots.
 357   // Likewise if am called with more VM slots, I will pop them.
 358   return (last_vmslots - this_vmslots);
 359 }
 360 
 361 
 362 // MemberName support
 363 
 364 // import sun_dyn_MemberName.*
 365 enum {
 366   IS_METHOD      = sun_dyn_MemberName::MN_IS_METHOD,
 367   IS_CONSTRUCTOR = sun_dyn_MemberName::MN_IS_CONSTRUCTOR,
 368   IS_FIELD       = sun_dyn_MemberName::MN_IS_FIELD,
 369   IS_TYPE        = sun_dyn_MemberName::MN_IS_TYPE,
 370   SEARCH_SUPERCLASSES = sun_dyn_MemberName::MN_SEARCH_SUPERCLASSES,
 371   SEARCH_INTERFACES   = sun_dyn_MemberName::MN_SEARCH_INTERFACES,
 372   ALL_KINDS      = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE,
 373   VM_INDEX_UNINITIALIZED = sun_dyn_MemberName::VM_INDEX_UNINITIALIZED
 374 };
 375 
 376 Handle MethodHandles::new_MemberName(TRAPS) {
 377   Handle empty;
 378   instanceKlassHandle k(THREAD, SystemDictionary::MemberName_klass());
 379   if (!k->is_initialized())  k->initialize(CHECK_(empty));
 380   return Handle(THREAD, k->allocate_instance(THREAD));
 381 }
 382 
 383 void MethodHandles::init_MemberName(oop mname_oop, oop target_oop) {
 384   if (target_oop->klass() == SystemDictionary::reflect_Field_klass()) {
 385     oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
 386     int slot  = java_lang_reflect_Field::slot(target_oop);  // fd.index()
 387     int mods  = java_lang_reflect_Field::modifiers(target_oop);
 388     klassOop k = java_lang_Class::as_klassOop(clazz);
 389     int offset = instanceKlass::cast(k)->offset_from_fields(slot);
 390     init_MemberName(mname_oop, k, accessFlags_from(mods), offset);
 391   } else {
 392     int decode_flags = 0; klassOop receiver_limit = NULL;
 393     methodOop m = MethodHandles::decode_method(target_oop,
 394                                                receiver_limit, decode_flags);
 395     bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
 396     init_MemberName(mname_oop, m, do_dispatch);
 397   }
 398 }
 399 
 400 void MethodHandles::init_MemberName(oop mname_oop, methodOop m, bool do_dispatch) {
 401   int flags = ((m->is_initializer() ? IS_CONSTRUCTOR : IS_METHOD)
 402                | (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS ));
 403   oop vmtarget = m;
 404   int vmindex  = methodOopDesc::invalid_vtable_index;  // implies no info yet
 405   if (!do_dispatch || (flags & IS_CONSTRUCTOR) || m->can_be_statically_bound())
 406     vmindex = methodOopDesc::nonvirtual_vtable_index; // implies never any dispatch
 407   assert(vmindex != VM_INDEX_UNINITIALIZED, "Java sentinel value");
 408   sun_dyn_MemberName::set_vmtarget(mname_oop, vmtarget);
 409   sun_dyn_MemberName::set_vmindex(mname_oop,  vmindex);
 410   sun_dyn_MemberName::set_flags(mname_oop,    flags);
 411   sun_dyn_MemberName::set_clazz(mname_oop,    Klass::cast(m->method_holder())->java_mirror());
 412 }
 413 
 414 void MethodHandles::init_MemberName(oop mname_oop, klassOop field_holder, AccessFlags mods, int offset) {
 415   int flags = (IS_FIELD | (jushort)( mods.as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS ));
 416   oop vmtarget = field_holder;
 417   int vmindex  = offset;  // determines the field uniquely when combined with static bit
 418   assert(vmindex != VM_INDEX_UNINITIALIZED, "bad alias on vmindex");
 419   sun_dyn_MemberName::set_vmtarget(mname_oop, vmtarget);
 420   sun_dyn_MemberName::set_vmindex(mname_oop,  vmindex);
 421   sun_dyn_MemberName::set_flags(mname_oop,    flags);
 422   sun_dyn_MemberName::set_clazz(mname_oop,    Klass::cast(field_holder)->java_mirror());
 423 }
 424 
 425 
 426 methodOop MethodHandles::decode_MemberName(oop mname, klassOop& receiver_limit_result, int& decode_flags_result) {
 427   int flags  = sun_dyn_MemberName::flags(mname);
 428   if ((flags & (IS_METHOD | IS_CONSTRUCTOR)) == 0)  return NULL;  // not invocable
 429   oop vmtarget = sun_dyn_MemberName::vmtarget(mname);
 430   int vmindex  = sun_dyn_MemberName::vmindex(mname);
 431   if (vmindex == VM_INDEX_UNINITIALIZED)  return NULL; // not resolved
 432   methodOop m = decode_vmtarget(vmtarget, vmindex, NULL, receiver_limit_result, decode_flags_result);
 433   oop clazz = sun_dyn_MemberName::clazz(mname);
 434   if (clazz != NULL && java_lang_Class::is_instance(clazz)) {
 435     klassOop klass = java_lang_Class::as_klassOop(clazz);
 436     if (klass != NULL)  receiver_limit_result = klass;
 437   }
 438   return m;
 439 }
 440 
 441 // An unresolved member name is a mere symbolic reference.
 442 // Resolving it plants a vmtarget/vmindex in it,
 443 // which refers dirctly to JVM internals.
 444 void MethodHandles::resolve_MemberName(Handle mname, TRAPS) {
 445   assert(sun_dyn_MemberName::is_instance(mname()), "");
 446 #ifdef ASSERT
 447   // If this assert throws, renegotiate the sentinel value used by the Java code,
 448   // so that it is distinct from any valid vtable index value, and any special
 449   // values defined in methodOopDesc::VtableIndexFlag.
 450   // The point of the slop is to give the Java code and the JVM some room
 451   // to independently specify sentinel values.
 452   const int sentinel_slop  = 10;
 453   const int sentinel_limit = methodOopDesc::highest_unused_vtable_index_value - sentinel_slop;
 454   assert(VM_INDEX_UNINITIALIZED < sentinel_limit, "Java sentinel != JVM sentinels");
 455 #endif
 456   if (sun_dyn_MemberName::vmindex(mname()) != VM_INDEX_UNINITIALIZED)
 457     return;  // already resolved
 458   oop defc_oop = sun_dyn_MemberName::clazz(mname());
 459   oop name_str = sun_dyn_MemberName::name(mname());
 460   oop type_str = sun_dyn_MemberName::type(mname());
 461   int flags    = sun_dyn_MemberName::flags(mname());
 462 
 463   if (defc_oop == NULL || name_str == NULL || type_str == NULL) {
 464     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve");
 465   }
 466   klassOop defc_klassOop = java_lang_Class::as_klassOop(defc_oop);
 467   defc_oop = NULL;  // safety
 468   if (defc_klassOop == NULL)  return;  // a primitive; no resolution possible
 469   if (!Klass::cast(defc_klassOop)->oop_is_instance()) {
 470     if (!Klass::cast(defc_klassOop)->oop_is_array())  return;
 471     defc_klassOop = SystemDictionary::Object_klass();
 472   }
 473   instanceKlassHandle defc(THREAD, defc_klassOop);
 474   defc_klassOop = NULL;  // safety
 475   if (defc.is_null()) {
 476     THROW_MSG(vmSymbols::java_lang_InternalError(), "primitive class");
 477   }
 478   defc->link_class(CHECK);
 479 
 480   // convert the external string name to an internal symbol
 481   symbolHandle name(THREAD, java_lang_String::as_symbol_or_null(name_str));
 482   if (name.is_null())  return;  // no such name
 483   name_str = NULL;  // safety
 484 
 485   Handle polymorphic_method_type;
 486   bool polymorphic_signature = false;
 487   if ((flags & ALL_KINDS) == IS_METHOD &&
 488       (defc() == SystemDictionary::MethodHandle_klass() &&
 489        methodOopDesc::is_method_handle_invoke_name(name())))
 490     polymorphic_signature = true;
 491 
 492   // convert the external string or reflective type to an internal signature
 493   symbolHandle type; {
 494     symbolOop type_sym = NULL;
 495     if (java_dyn_MethodType::is_instance(type_str)) {
 496       type_sym = java_dyn_MethodType::as_signature(type_str, polymorphic_signature, CHECK);
 497       if (polymorphic_signature)
 498         polymorphic_method_type = Handle(THREAD, type_str);  //preserve exactly
 499     } else if (java_lang_Class::is_instance(type_str)) {
 500       type_sym = java_lang_Class::as_signature(type_str, false, CHECK);
 501     } else if (java_lang_String::is_instance(type_str)) {
 502       if (polymorphic_signature) {
 503         type     = java_lang_String::as_symbol(type_str, CHECK);
 504       } else {
 505         type_sym = java_lang_String::as_symbol_or_null(type_str);
 506       }
 507     } else {
 508       THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized type");
 509     }
 510     if (type_sym != NULL)
 511       type = symbolHandle(THREAD, type_sym);
 512   }
 513   if (type.is_null())  return;  // no such signature exists in the VM
 514   type_str = NULL; // safety
 515 
 516   // Time to do the lookup.
 517   switch (flags & ALL_KINDS) {
 518   case IS_METHOD:
 519     {
 520       CallInfo result;
 521       {
 522         EXCEPTION_MARK;
 523         if ((flags & JVM_ACC_STATIC) != 0) {
 524           LinkResolver::resolve_static_call(result,
 525                         defc, name, type, KlassHandle(), false, false, THREAD);
 526         } else if (defc->is_interface()) {
 527           LinkResolver::resolve_interface_call(result, Handle(), defc,
 528                         defc, name, type, KlassHandle(), false, false, THREAD);
 529         } else {
 530           LinkResolver::resolve_virtual_call(result, Handle(), defc,
 531                         defc, name, type, KlassHandle(), false, false, THREAD);
 532         }
 533         if (HAS_PENDING_EXCEPTION) {
 534           CLEAR_PENDING_EXCEPTION;
 535           break;  // go to second chance
 536         }
 537       }
 538       methodHandle m = result.resolved_method();
 539       oop vmtarget = NULL;
 540       int vmindex = methodOopDesc::nonvirtual_vtable_index;
 541       if (defc->is_interface()) {
 542         vmindex = klassItable::compute_itable_index(m());
 543         assert(vmindex >= 0, "");
 544       } else if (result.has_vtable_index()) {
 545         vmindex = result.vtable_index();
 546         assert(vmindex >= 0, "");
 547       }
 548       assert(vmindex != VM_INDEX_UNINITIALIZED, "");
 549       if (vmindex < 0) {
 550         assert(result.is_statically_bound(), "");
 551         vmtarget = m();
 552       } else {
 553         vmtarget = result.resolved_klass()->as_klassOop();
 554       }
 555       int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
 556       sun_dyn_MemberName::set_vmtarget(mname(), vmtarget);
 557       sun_dyn_MemberName::set_vmindex(mname(),  vmindex);
 558       sun_dyn_MemberName::set_modifiers(mname(), mods);
 559       DEBUG_ONLY(int junk; klassOop junk2);
 560       assert(decode_MemberName(mname(), junk2, junk) == result.resolved_method()(),
 561              "properly stored for later decoding");
 562       return;
 563     }
 564   case IS_CONSTRUCTOR:
 565     {
 566       CallInfo result;
 567       {
 568         EXCEPTION_MARK;
 569         if (name() == vmSymbols::object_initializer_name()) {
 570           LinkResolver::resolve_special_call(result,
 571                         defc, name, type, KlassHandle(), false, THREAD);
 572         } else {
 573           break;                // will throw after end of switch
 574         }
 575         if (HAS_PENDING_EXCEPTION) {
 576           CLEAR_PENDING_EXCEPTION;
 577           return;
 578         }
 579       }
 580       assert(result.is_statically_bound(), "");
 581       methodHandle m = result.resolved_method();
 582       oop vmtarget = m();
 583       int vmindex  = methodOopDesc::nonvirtual_vtable_index;
 584       int mods     = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
 585       sun_dyn_MemberName::set_vmtarget(mname(), vmtarget);
 586       sun_dyn_MemberName::set_vmindex(mname(),  vmindex);
 587       sun_dyn_MemberName::set_modifiers(mname(), mods);
 588       DEBUG_ONLY(int junk; klassOop junk2);
 589       assert(decode_MemberName(mname(), junk2, junk) == result.resolved_method()(),
 590              "properly stored for later decoding");
 591       return;
 592     }
 593   case IS_FIELD:
 594     {
 595       // This is taken from LinkResolver::resolve_field, sans access checks.
 596       fieldDescriptor fd; // find_field initializes fd if found
 597       KlassHandle sel_klass(THREAD, instanceKlass::cast(defc())->find_field(name(), type(), &fd));
 598       // check if field exists; i.e., if a klass containing the field def has been selected
 599       if (sel_klass.is_null())  return;
 600       oop vmtarget = sel_klass->as_klassOop();
 601       int vmindex  = fd.offset();
 602       int mods     = (fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS);
 603       if (vmindex == VM_INDEX_UNINITIALIZED)  break;  // should not happen
 604       sun_dyn_MemberName::set_vmtarget(mname(),  vmtarget);
 605       sun_dyn_MemberName::set_vmindex(mname(),   vmindex);
 606       sun_dyn_MemberName::set_modifiers(mname(), mods);
 607       return;
 608     }
 609   default:
 610     THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 611   }
 612 
 613   // Second chance.
 614   if (polymorphic_method_type.not_null()) {
 615     // Look on a non-null class loader.
 616     Handle cur_class_loader;
 617     const int nptypes = java_dyn_MethodType::ptype_count(polymorphic_method_type());
 618     for (int i = 0; i <= nptypes; i++) {
 619       oop type_mirror;
 620       if (i < nptypes)  type_mirror = java_dyn_MethodType::ptype(polymorphic_method_type(), i);
 621       else              type_mirror = java_dyn_MethodType::rtype(polymorphic_method_type());
 622       klassOop example_type = java_lang_Class::as_klassOop(type_mirror);
 623       if (example_type == NULL)  continue;
 624       oop class_loader = Klass::cast(example_type)->class_loader();
 625       if (class_loader == NULL || class_loader == cur_class_loader())  continue;
 626       cur_class_loader = Handle(THREAD, class_loader);
 627       methodOop m = SystemDictionary::find_method_handle_invoke(name,
 628                                                                 type,
 629                                                                 KlassHandle(THREAD, example_type),
 630                                                                 THREAD);
 631       if (HAS_PENDING_EXCEPTION) {
 632         CLEAR_PENDING_EXCEPTION;
 633         m = NULL;
 634         // try again with a different class loader...
 635       }
 636       if (m != NULL) {
 637         int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
 638         sun_dyn_MemberName::set_vmtarget(mname(),  m);
 639         sun_dyn_MemberName::set_vmindex(mname(),   m->vtable_index());
 640         sun_dyn_MemberName::set_modifiers(mname(), mods);
 641         return;
 642       }
 643     }
 644   }
 645 }
 646 
 647 // Conversely, a member name which is only initialized from JVM internals
 648 // may have null defc, name, and type fields.
 649 // Resolving it plants a vmtarget/vmindex in it,
 650 // which refers directly to JVM internals.
 651 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
 652   assert(sun_dyn_MemberName::is_instance(mname()), "");
 653   oop vmtarget = sun_dyn_MemberName::vmtarget(mname());
 654   int vmindex  = sun_dyn_MemberName::vmindex(mname());
 655   if (vmtarget == NULL || vmindex == VM_INDEX_UNINITIALIZED) {
 656     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
 657   }
 658 
 659   bool have_defc = (sun_dyn_MemberName::clazz(mname()) != NULL);
 660   bool have_name = (sun_dyn_MemberName::name(mname()) != NULL);
 661   bool have_type = (sun_dyn_MemberName::type(mname()) != NULL);
 662   int flags      = sun_dyn_MemberName::flags(mname());
 663 
 664   if (suppress != 0) {
 665     if (suppress & _suppress_defc)  have_defc = true;
 666     if (suppress & _suppress_name)  have_name = true;
 667     if (suppress & _suppress_type)  have_type = true;
 668   }
 669 
 670   if (have_defc && have_name && have_type)  return;  // nothing needed
 671 
 672   switch (flags & ALL_KINDS) {
 673   case IS_METHOD:
 674   case IS_CONSTRUCTOR:
 675     {
 676       klassOop receiver_limit = NULL;
 677       int      decode_flags   = 0;
 678       methodHandle m(THREAD, decode_vmtarget(vmtarget, vmindex, NULL,
 679                                              receiver_limit, decode_flags));
 680       if (m.is_null())  break;
 681       if (!have_defc) {
 682         klassOop defc = m->method_holder();
 683         if (receiver_limit != NULL && receiver_limit != defc
 684             && Klass::cast(receiver_limit)->is_subtype_of(defc))
 685           defc = receiver_limit;
 686         sun_dyn_MemberName::set_clazz(mname(), Klass::cast(defc)->java_mirror());
 687       }
 688       if (!have_name) {
 689         //not java_lang_String::create_from_symbol; let's intern member names
 690         Handle name = StringTable::intern(m->name(), CHECK);
 691         sun_dyn_MemberName::set_name(mname(), name());
 692       }
 693       if (!have_type) {
 694         Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
 695         sun_dyn_MemberName::set_type(mname(), type());
 696       }
 697       return;
 698     }
 699   case IS_FIELD:
 700     {
 701       // This is taken from LinkResolver::resolve_field, sans access checks.
 702       if (!vmtarget->is_klass())  break;
 703       if (!Klass::cast((klassOop) vmtarget)->oop_is_instance())  break;
 704       instanceKlassHandle defc(THREAD, (klassOop) vmtarget);
 705       bool is_static = ((flags & JVM_ACC_STATIC) != 0);
 706       fieldDescriptor fd; // find_field initializes fd if found
 707       if (!defc->find_field_from_offset(vmindex, is_static, &fd))
 708         break;                  // cannot expand
 709       if (!have_defc) {
 710         sun_dyn_MemberName::set_clazz(mname(), defc->java_mirror());
 711       }
 712       if (!have_name) {
 713         //not java_lang_String::create_from_symbol; let's intern member names
 714         Handle name = StringTable::intern(fd.name(), CHECK);
 715         sun_dyn_MemberName::set_name(mname(), name());
 716       }
 717       if (!have_type) {
 718         Handle type = java_lang_String::create_from_symbol(fd.signature(), CHECK);
 719         sun_dyn_MemberName::set_type(mname(), type());
 720       }
 721       return;
 722     }
 723   }
 724   THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
 725 }
 726 
 727 int MethodHandles::find_MemberNames(klassOop k,
 728                                     symbolOop name, symbolOop sig,
 729                                     int mflags, klassOop caller,
 730                                     int skip, objArrayOop results) {
 731   DEBUG_ONLY(No_Safepoint_Verifier nsv);
 732   // this code contains no safepoints!
 733 
 734   // %%% take caller into account!
 735 
 736   if (k == NULL || !Klass::cast(k)->oop_is_instance())  return -1;
 737 
 738   int rfill = 0, rlimit = results->length(), rskip = skip;
 739   // overflow measurement:
 740   int overflow = 0, overflow_limit = MAX2(1000, rlimit);
 741 
 742   int match_flags = mflags;
 743   bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
 744   bool search_intfc  = ((match_flags & SEARCH_INTERFACES)   != 0);
 745   bool local_only = !(search_superc | search_intfc);
 746   bool classes_only = false;
 747 
 748   if (name != NULL) {
 749     if (name->utf8_length() == 0)  return 0; // a match is not possible
 750   }
 751   if (sig != NULL) {
 752     if (sig->utf8_length() == 0)  return 0; // a match is not possible
 753     if (sig->byte_at(0) == '(')
 754       match_flags &= ~(IS_FIELD | IS_TYPE);
 755     else
 756       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
 757   }
 758 
 759   if ((match_flags & IS_TYPE) != 0) {
 760     // NYI, and Core Reflection works quite well for this query
 761   }
 762 
 763   if ((match_flags & IS_FIELD) != 0) {
 764     for (FieldStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
 765       if (name != NULL && st.name() != name)
 766           continue;
 767       if (sig != NULL && st.signature() != sig)
 768         continue;
 769       // passed the filters
 770       if (rskip > 0) {
 771         --rskip;
 772       } else if (rfill < rlimit) {
 773         oop result = results->obj_at(rfill++);
 774         if (!sun_dyn_MemberName::is_instance(result))
 775           return -99;  // caller bug!
 776         MethodHandles::init_MemberName(result, st.klass()->as_klassOop(), st.access_flags(), st.offset());
 777       } else if (++overflow >= overflow_limit) {
 778         match_flags = 0; break; // got tired of looking at overflow
 779       }
 780     }
 781   }
 782 
 783   if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
 784     // watch out for these guys:
 785     symbolOop init_name   = vmSymbols::object_initializer_name();
 786     symbolOop clinit_name = vmSymbols::class_initializer_name();
 787     if (name == clinit_name)  clinit_name = NULL; // hack for exposing <clinit>
 788     bool negate_name_test = false;
 789     // fix name so that it captures the intention of IS_CONSTRUCTOR
 790     if (!(match_flags & IS_METHOD)) {
 791       // constructors only
 792       if (name == NULL) {
 793         name = init_name;
 794       } else if (name != init_name) {
 795         return 0;               // no constructors of this method name
 796       }
 797     } else if (!(match_flags & IS_CONSTRUCTOR)) {
 798       // methods only
 799       if (name == NULL) {
 800         name = init_name;
 801         negate_name_test = true; // if we see the name, we *omit* the entry
 802       } else if (name == init_name) {
 803         return 0;               // no methods of this constructor name
 804       }
 805     } else {
 806       // caller will accept either sort; no need to adjust name
 807     }
 808     for (MethodStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
 809       methodOop m = st.method();
 810       symbolOop m_name = m->name();
 811       if (m_name == clinit_name)
 812         continue;
 813       if (name != NULL && ((m_name != name) ^ negate_name_test))
 814           continue;
 815       if (sig != NULL && m->signature() != sig)
 816         continue;
 817       // passed the filters
 818       if (rskip > 0) {
 819         --rskip;
 820       } else if (rfill < rlimit) {
 821         oop result = results->obj_at(rfill++);
 822         if (!sun_dyn_MemberName::is_instance(result))
 823           return -99;  // caller bug!
 824         MethodHandles::init_MemberName(result, m, true);
 825       } else if (++overflow >= overflow_limit) {
 826         match_flags = 0; break; // got tired of looking at overflow
 827       }
 828     }
 829   }
 830 
 831   // return number of elements we at leasted wanted to initialize
 832   return rfill + overflow;
 833 }
 834 
 835 
 836 // Decode this java.lang.Class object into an instanceKlass, if possible.
 837 // Throw IAE if not
 838 instanceKlassHandle MethodHandles::resolve_instance_klass(oop java_mirror_oop, TRAPS) {
 839   instanceKlassHandle empty;
 840   klassOop caller = NULL;
 841   if (java_lang_Class::is_instance(java_mirror_oop)) {
 842     caller = java_lang_Class::as_klassOop(java_mirror_oop);
 843   }
 844   if (caller == NULL || !Klass::cast(caller)->oop_is_instance()) {
 845     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "not a class", empty);
 846   }
 847   return instanceKlassHandle(THREAD, caller);
 848 }
 849 
 850 
 851 
 852 // Decode the vmtarget field of a method handle.
 853 // Sanitize out methodOops, klassOops, and any other non-Java data.
 854 // This is for debugging and reflection.
 855 oop MethodHandles::encode_target(Handle mh, int format, TRAPS) {
 856   assert(java_dyn_MethodHandle::is_instance(mh()), "must be a MH");
 857   if (format == ETF_HANDLE_OR_METHOD_NAME) {
 858     oop target = java_dyn_MethodHandle::vmtarget(mh());
 859     if (target == NULL) {
 860       return NULL;                // unformed MH
 861     }
 862     klassOop tklass = target->klass();
 863     if (Klass::cast(tklass)->is_subclass_of(SystemDictionary::Object_klass())) {
 864       return target;              // target is another MH (or something else?)
 865     }
 866   }
 867   if (format == ETF_DIRECT_HANDLE) {
 868     oop target = mh();
 869     for (;;) {
 870       if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
 871         return target;
 872       }
 873       if (!java_dyn_MethodHandle::is_instance(target)){
 874         return NULL;                // unformed MH
 875       }
 876       target = java_dyn_MethodHandle::vmtarget(target);
 877     }
 878   }
 879   // cases of metadata in MH.vmtarget:
 880   // - AMH can have methodOop for static invoke with bound receiver
 881   // - DMH can have methodOop for static invoke (on variable receiver)
 882   // - DMH can have klassOop for dispatched (non-static) invoke
 883   klassOop receiver_limit = NULL;
 884   int decode_flags = 0;
 885   methodOop m = decode_MethodHandle(mh(), receiver_limit, decode_flags);
 886   if (m == NULL)  return NULL;
 887   switch (format) {
 888   case ETF_REFLECT_METHOD:
 889     // same as jni_ToReflectedMethod:
 890     if (m->is_initializer()) {
 891       return Reflection::new_constructor(m, THREAD);
 892     } else {
 893       return Reflection::new_method(m, UseNewReflection, false, THREAD);
 894     }
 895 
 896   case ETF_HANDLE_OR_METHOD_NAME:   // method, not handle
 897   case ETF_METHOD_NAME:
 898     {
 899       if (SystemDictionary::MemberName_klass() == NULL)  break;
 900       instanceKlassHandle mname_klass(THREAD, SystemDictionary::MemberName_klass());
 901       mname_klass->initialize(CHECK_NULL);
 902       Handle mname = mname_klass->allocate_instance_handle(CHECK_NULL);
 903       sun_dyn_MemberName::set_vmindex(mname(), VM_INDEX_UNINITIALIZED);
 904       bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
 905       init_MemberName(mname(), m, do_dispatch);
 906       expand_MemberName(mname, 0, CHECK_NULL);
 907       return mname();
 908     }
 909   }
 910 
 911   // Unknown format code.
 912   char msg[50];
 913   jio_snprintf(msg, sizeof(msg), "unknown getTarget format=%d", format);
 914   THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), msg);
 915 }
 916 
 917 static const char* always_null_names[] = {
 918   "java/lang/Void",
 919   "java/lang/Null",
 920   //"java/lang/Nothing",
 921   "sun/dyn/empty/Empty",
 922   NULL
 923 };
 924 
 925 static bool is_always_null_type(klassOop klass) {
 926   if (!Klass::cast(klass)->oop_is_instance())  return false;
 927   instanceKlass* ik = instanceKlass::cast(klass);
 928   // Must be on the boot class path:
 929   if (ik->class_loader() != NULL)  return false;
 930   // Check the name.
 931   symbolOop name = ik->name();
 932   for (int i = 0; ; i++) {
 933     const char* test_name = always_null_names[i];
 934     if (test_name == NULL)  break;
 935     if (name->equals(test_name))
 936       return true;
 937   }
 938   return false;
 939 }
 940 
 941 bool MethodHandles::class_cast_needed(klassOop src, klassOop dst) {
 942   if (src == dst || dst == SystemDictionary::Object_klass())
 943     return false;                               // quickest checks
 944   Klass* srck = Klass::cast(src);
 945   Klass* dstk = Klass::cast(dst);
 946   if (dstk->is_interface()) {
 947     // interface receivers can safely be viewed as untyped,
 948     // because interface calls always include a dynamic check
 949     //dstk = Klass::cast(SystemDictionary::Object_klass());
 950     return false;
 951   }
 952   if (srck->is_interface()) {
 953     // interface arguments must be viewed as untyped
 954     //srck = Klass::cast(SystemDictionary::Object_klass());
 955     return true;
 956   }
 957   if (is_always_null_type(src)) {
 958     // some source types are known to be never instantiated;
 959     // they represent references which are always null
 960     // such null references never fail to convert safely
 961     return false;
 962   }
 963   return !srck->is_subclass_of(dstk->as_klassOop());
 964 }
 965 
 966 static oop object_java_mirror() {
 967   return Klass::cast(SystemDictionary::Object_klass())->java_mirror();
 968 }
 969 
 970 bool MethodHandles::same_basic_type_for_arguments(BasicType src,
 971                                                   BasicType dst,
 972                                                   bool raw,
 973                                                   bool for_return) {
 974   if (for_return) {
 975     // return values can always be forgotten:
 976     if (dst == T_VOID)  return true;
 977     if (src == T_VOID)  return raw && (dst == T_INT);
 978     // We allow caller to receive a garbage int, which is harmless.
 979     // This trick is pulled by trusted code (see VerifyType.canPassRaw).
 980   }
 981   assert(src != T_VOID && dst != T_VOID, "should not be here");
 982   if (src == dst)  return true;
 983   if (type2size[src] != type2size[dst])  return false;
 984   if (src == T_OBJECT || dst == T_OBJECT)  return false;
 985   if (raw)  return true;  // bitwise reinterpretation; caller guarantees safety
 986   // allow reinterpretation casts for integral widening
 987   if (is_subword_type(src)) { // subwords can fit in int or other subwords
 988     if (dst == T_INT)         // any subword fits in an int
 989       return true;
 990     if (src == T_BOOLEAN)     // boolean fits in any subword
 991       return is_subword_type(dst);
 992     if (src == T_BYTE && dst == T_SHORT)
 993       return true;            // remaining case: byte fits in short
 994   }
 995   // allow float/fixed reinterpretation casts
 996   if (src == T_FLOAT)   return dst == T_INT;
 997   if (src == T_INT)     return dst == T_FLOAT;
 998   if (src == T_DOUBLE)  return dst == T_LONG;
 999   if (src == T_LONG)    return dst == T_DOUBLE;
1000   return false;
1001 }
1002 
1003 const char* MethodHandles::check_method_receiver(methodOop m,
1004                                                  klassOop passed_recv_type) {
1005   assert(!m->is_static(), "caller resp.");
1006   if (passed_recv_type == NULL)
1007     return "receiver type is primitive";
1008   if (class_cast_needed(passed_recv_type, m->method_holder())) {
1009     Klass* formal = Klass::cast(m->method_holder());
1010     return SharedRuntime::generate_class_cast_message("receiver type",
1011                                                       formal->external_name());
1012   }
1013   return NULL;                  // checks passed
1014 }
1015 
1016 // Verify that m's signature can be called type-safely by a method handle
1017 // of the given method type 'mtype'.
1018 // It takes a TRAPS argument because it must perform symbol lookups.
1019 void MethodHandles::verify_method_signature(methodHandle m,
1020                                             Handle mtype,
1021                                             int first_ptype_pos,
1022                                             KlassHandle insert_ptype,
1023                                             TRAPS) {
1024   objArrayHandle ptypes(THREAD, java_dyn_MethodType::ptypes(mtype()));
1025   int pnum = first_ptype_pos;
1026   int pmax = ptypes->length();
1027   int mnum = 0;                 // method argument
1028   const char* err = NULL;
1029   for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) {
1030     oop ptype_oop = NULL;
1031     if (ss.at_return_type()) {
1032       if (pnum != pmax)
1033         { err = "too many arguments"; break; }
1034       ptype_oop = java_dyn_MethodType::rtype(mtype());
1035     } else {
1036       if (pnum >= pmax)
1037         { err = "not enough arguments"; break; }
1038       if (pnum >= 0)
1039         ptype_oop = ptypes->obj_at(pnum);
1040       else if (insert_ptype.is_null())
1041         ptype_oop = NULL;
1042       else
1043         ptype_oop = insert_ptype->java_mirror();
1044       pnum += 1;
1045       mnum += 1;
1046     }
1047     klassOop  pklass = NULL;
1048     BasicType ptype  = T_OBJECT;
1049     if (ptype_oop != NULL)
1050       ptype = java_lang_Class::as_BasicType(ptype_oop, &pklass);
1051     else
1052       // null does not match any non-reference; use Object to report the error
1053       pklass = SystemDictionary::Object_klass();
1054     klassOop  mklass = NULL;
1055     BasicType mtype  = ss.type();
1056     if (mtype == T_ARRAY)  mtype = T_OBJECT; // fold all refs to T_OBJECT
1057     if (mtype == T_OBJECT) {
1058       if (ptype_oop == NULL) {
1059         // null matches any reference
1060         continue;
1061       }
1062       KlassHandle pklass_handle(THREAD, pklass); pklass = NULL;
1063       // If we fail to resolve types at this point, we will throw an error.
1064       symbolOop    name_oop = ss.as_symbol(CHECK);
1065       symbolHandle name(THREAD, name_oop);
1066       instanceKlass* mk = instanceKlass::cast(m->method_holder());
1067       Handle loader(THREAD, mk->class_loader());
1068       Handle domain(THREAD, mk->protection_domain());
1069       mklass = SystemDictionary::resolve_or_null(name, loader, domain, CHECK);
1070       pklass = pklass_handle();
1071       if (mklass == NULL && pklass != NULL &&
1072           Klass::cast(pklass)->name() == name() &&
1073           m->is_method_handle_invoke()) {
1074         // Assume a match.  We can't really decode the signature of MH.invoke*.
1075         continue;
1076       }
1077     }
1078     if (!ss.at_return_type()) {
1079       err = check_argument_type_change(ptype, pklass, mtype, mklass, mnum);
1080     } else {
1081       err = check_return_type_change(mtype, mklass, ptype, pklass); // note reversal!
1082     }
1083     if (err != NULL)  break;
1084   }
1085 
1086   if (err != NULL) {
1087     THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1088   }
1089 }
1090 
1091 // Main routine for verifying the MethodHandle.type of a proposed
1092 // direct or bound-direct method handle.
1093 void MethodHandles::verify_method_type(methodHandle m,
1094                                        Handle mtype,
1095                                        bool has_bound_recv,
1096                                        KlassHandle bound_recv_type,
1097                                        TRAPS) {
1098   bool m_needs_receiver = !m->is_static();
1099 
1100   const char* err = NULL;
1101 
1102   int first_ptype_pos = m_needs_receiver ? 1 : 0;
1103   if (has_bound_recv) {
1104     first_ptype_pos -= 1;  // ptypes do not include the bound argument; start earlier in them
1105     if (m_needs_receiver && bound_recv_type.is_null())
1106       { err = "bound receiver is not an object"; goto die; }
1107   }
1108 
1109   if (m_needs_receiver && err == NULL) {
1110     objArrayOop ptypes = java_dyn_MethodType::ptypes(mtype());
1111     if (ptypes->length() < first_ptype_pos)
1112       { err = "receiver argument is missing"; goto die; }
1113     if (has_bound_recv)
1114       err = check_method_receiver(m(), bound_recv_type->as_klassOop());
1115     else
1116       err = check_method_receiver(m(), java_lang_Class::as_klassOop(ptypes->obj_at(first_ptype_pos-1)));
1117     if (err != NULL)  goto die;
1118   }
1119 
1120   // Check the other arguments for mistypes.
1121   verify_method_signature(m, mtype, first_ptype_pos, bound_recv_type, CHECK);
1122   return;
1123 
1124  die:
1125   THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1126 }
1127 
1128 void MethodHandles::verify_vmslots(Handle mh, TRAPS) {
1129   // Verify vmslots.
1130   int check_slots = argument_slot_count(java_dyn_MethodHandle::type(mh()));
1131   if (java_dyn_MethodHandle::vmslots(mh()) != check_slots) {
1132     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH");
1133   }
1134 }
1135 
1136 void MethodHandles::verify_vmargslot(Handle mh, int argnum, int argslot, TRAPS) {
1137   // Verify that argslot points at the given argnum.
1138   int check_slot = argument_slot(java_dyn_MethodHandle::type(mh()), argnum);
1139   if (argslot != check_slot || argslot < 0) {
1140     const char* fmt = "for argnum of %d, vmargslot is %d, should be %d";
1141     size_t msglen = strlen(fmt) + 3*11 + 1;
1142     char* msg = NEW_RESOURCE_ARRAY(char, msglen);
1143     jio_snprintf(msg, msglen, fmt, argnum, argslot, check_slot);
1144     THROW_MSG(vmSymbols::java_lang_InternalError(), msg);
1145   }
1146 }
1147 
1148 // Verify the correspondence between two method types.
1149 // Apart from the advertised changes, caller method type X must
1150 // be able to invoke the callee method Y type with no violations
1151 // of type integrity.
1152 // Return NULL if all is well, else a short error message.
1153 const char* MethodHandles::check_method_type_change(oop src_mtype, int src_beg, int src_end,
1154                                                     int insert_argnum, oop insert_type,
1155                                                     int change_argnum, oop change_type,
1156                                                     int delete_argnum,
1157                                                     oop dst_mtype, int dst_beg, int dst_end,
1158                                                     bool raw) {
1159   objArrayOop src_ptypes = java_dyn_MethodType::ptypes(src_mtype);
1160   objArrayOop dst_ptypes = java_dyn_MethodType::ptypes(dst_mtype);
1161 
1162   int src_max = src_ptypes->length();
1163   int dst_max = dst_ptypes->length();
1164 
1165   if (src_end == -1)  src_end = src_max;
1166   if (dst_end == -1)  dst_end = dst_max;
1167 
1168   assert(0 <= src_beg && src_beg <= src_end && src_end <= src_max, "oob");
1169   assert(0 <= dst_beg && dst_beg <= dst_end && dst_end <= dst_max, "oob");
1170 
1171   // pending actions; set to -1 when done:
1172   int ins_idx = insert_argnum, chg_idx = change_argnum, del_idx = delete_argnum;
1173 
1174   const char* err = NULL;
1175 
1176   // Walk along each array of parameter types, including a virtual
1177   // NULL end marker at the end of each.
1178   for (int src_idx = src_beg, dst_idx = dst_beg;
1179        (src_idx <= src_end && dst_idx <= dst_end);
1180        src_idx++, dst_idx++) {
1181     oop src_type = (src_idx == src_end) ? oop(NULL) : src_ptypes->obj_at(src_idx);
1182     oop dst_type = (dst_idx == dst_end) ? oop(NULL) : dst_ptypes->obj_at(dst_idx);
1183     bool fix_null_src_type = false;
1184 
1185     // Perform requested edits.
1186     if (ins_idx == src_idx) {
1187       // note that the inserted guy is never affected by a change or deletion
1188       ins_idx = -1;
1189       src_type = insert_type;
1190       fix_null_src_type = true;
1191       --src_idx;                // back up to process src type on next loop
1192       src_idx = src_end;
1193     } else {
1194       // note that the changed guy can be immediately deleted
1195       if (chg_idx == src_idx) {
1196         chg_idx = -1;
1197         assert(src_idx < src_end, "oob");
1198         src_type = change_type;
1199         fix_null_src_type = true;
1200       }
1201       if (del_idx == src_idx) {
1202         del_idx = -1;
1203         assert(src_idx < src_end, "oob");
1204         --dst_idx;
1205         continue;               // rerun loop after skipping this position
1206       }
1207     }
1208 
1209     if (src_type == NULL && fix_null_src_type)
1210       // explicit null in this case matches any dest reference
1211       src_type = (java_lang_Class::is_primitive(dst_type) ? object_java_mirror() : dst_type);
1212 
1213     // Compare the two argument types.
1214     if (src_type != dst_type) {
1215       if (src_type == NULL)  return "not enough arguments";
1216       if (dst_type == NULL)  return "too many arguments";
1217       err = check_argument_type_change(src_type, dst_type, dst_idx, raw);
1218       if (err != NULL)  return err;
1219     }
1220   }
1221 
1222   // Now compare return types also.
1223   oop src_rtype = java_dyn_MethodType::rtype(src_mtype);
1224   oop dst_rtype = java_dyn_MethodType::rtype(dst_mtype);
1225   if (src_rtype != dst_rtype) {
1226     err = check_return_type_change(dst_rtype, src_rtype, raw); // note reversal!
1227     if (err != NULL)  return err;
1228   }
1229 
1230   assert(err == NULL, "");
1231   return NULL;  // all is well
1232 }
1233 
1234 
1235 const char* MethodHandles::check_argument_type_change(BasicType src_type,
1236                                                       klassOop src_klass,
1237                                                       BasicType dst_type,
1238                                                       klassOop dst_klass,
1239                                                       int argnum,
1240                                                       bool raw) {
1241   const char* err = NULL;
1242   bool for_return = (argnum < 0);
1243 
1244   // just in case:
1245   if (src_type == T_ARRAY)  src_type = T_OBJECT;
1246   if (dst_type == T_ARRAY)  dst_type = T_OBJECT;
1247 
1248   // Produce some nice messages if VerifyMethodHandles is turned on:
1249   if (!same_basic_type_for_arguments(src_type, dst_type, raw, for_return)) {
1250     if (src_type == T_OBJECT) {
1251       if (raw && dst_type == T_INT && is_always_null_type(src_klass))
1252         return NULL;    // OK to convert a null pointer to a garbage int
1253       err = ((argnum >= 0)
1254              ? "type mismatch: passing a %s for method argument #%d, which expects primitive %s"
1255              : "type mismatch: returning a %s, but caller expects primitive %s");
1256     } else if (dst_type == T_OBJECT) {
1257       err = ((argnum >= 0)
1258              ? "type mismatch: passing a primitive %s for method argument #%d, which expects %s"
1259              : "type mismatch: returning a primitive %s, but caller expects %s");
1260     } else {
1261       err = ((argnum >= 0)
1262              ? "type mismatch: passing a %s for method argument #%d, which expects %s"
1263              : "type mismatch: returning a %s, but caller expects %s");
1264     }
1265   } else if (src_type == T_OBJECT && dst_type == T_OBJECT &&
1266              class_cast_needed(src_klass, dst_klass)) {
1267     if (!class_cast_needed(dst_klass, src_klass)) {
1268       if (raw)
1269         return NULL;    // reverse cast is OK; the MH target is trusted to enforce it
1270       err = ((argnum >= 0)
1271              ? "cast required: passing a %s for method argument #%d, which expects %s"
1272              : "cast required: returning a %s, but caller expects %s");
1273     } else {
1274       err = ((argnum >= 0)
1275              ? "reference mismatch: passing a %s for method argument #%d, which expects %s"
1276              : "reference mismatch: returning a %s, but caller expects %s");
1277     }
1278   } else {
1279     // passed the obstacle course
1280     return NULL;
1281   }
1282 
1283   // format, format, format
1284   const char* src_name = type2name(src_type);
1285   const char* dst_name = type2name(dst_type);
1286   if (src_type == T_OBJECT)  src_name = Klass::cast(src_klass)->external_name();
1287   if (dst_type == T_OBJECT)  dst_name = Klass::cast(dst_klass)->external_name();
1288   if (src_name == NULL)  src_name = "unknown type";
1289   if (dst_name == NULL)  dst_name = "unknown type";
1290 
1291   size_t msglen = strlen(err) + strlen(src_name) + strlen(dst_name) + (argnum < 10 ? 1 : 11);
1292   char* msg = NEW_RESOURCE_ARRAY(char, msglen + 1);
1293   if (argnum >= 0) {
1294     assert(strstr(err, "%d") != NULL, "");
1295     jio_snprintf(msg, msglen, err, src_name, argnum, dst_name);
1296   } else {
1297     assert(strstr(err, "%d") == NULL, "");
1298     jio_snprintf(msg, msglen, err, src_name,         dst_name);
1299   }
1300   return msg;
1301 }
1302 
1303 // Compute the depth within the stack of the given argument, i.e.,
1304 // the combined size of arguments to the right of the given argument.
1305 // For the last argument (ptypes.length-1) this will be zero.
1306 // For the first argument (0) this will be the size of all
1307 // arguments but that one.  For the special number -1, this
1308 // will be the size of all arguments, including the first.
1309 // If the argument is neither -1 nor a valid argument index,
1310 // then return a negative number.  Otherwise, the result
1311 // is in the range [0..vmslots] inclusive.
1312 int MethodHandles::argument_slot(oop method_type, int arg) {
1313   objArrayOop ptypes = java_dyn_MethodType::ptypes(method_type);
1314   int argslot = 0;
1315   int len = ptypes->length();
1316   if (arg < -1 || arg >= len)  return -99;
1317   for (int i = len-1; i > arg; i--) {
1318     BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
1319     argslot += type2size[bt];
1320   }
1321   assert(argument_slot_to_argnum(method_type, argslot) == arg, "inverse works");
1322   return argslot;
1323 }
1324 
1325 // Given a slot number, return the argument number.
1326 int MethodHandles::argument_slot_to_argnum(oop method_type, int query_argslot) {
1327   objArrayOop ptypes = java_dyn_MethodType::ptypes(method_type);
1328   int argslot = 0;
1329   int len = ptypes->length();
1330   for (int i = len-1; i >= 0; i--) {
1331     if (query_argslot == argslot)  return i;
1332     BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
1333     argslot += type2size[bt];
1334   }
1335   // return pseudo-arg deepest in stack:
1336   if (query_argslot == argslot)  return -1;
1337   return -99;                   // oob slot, or splitting a double-slot arg
1338 }
1339 
1340 methodHandle MethodHandles::dispatch_decoded_method(methodHandle m,
1341                                                     KlassHandle receiver_limit,
1342                                                     int decode_flags,
1343                                                     KlassHandle receiver_klass,
1344                                                     TRAPS) {
1345   assert((decode_flags & ~_DMF_DIRECT_MASK) == 0, "must be direct method reference");
1346   assert((decode_flags & _dmf_has_receiver) != 0, "must have a receiver or first reference argument");
1347 
1348   if (!m->is_static() &&
1349       (receiver_klass.is_null() || !receiver_klass->is_subtype_of(m->method_holder())))
1350     // given type does not match class of method, or receiver is null!
1351     // caller should have checked this, but let's be extra careful...
1352     return methodHandle();
1353 
1354   if (receiver_limit.not_null() &&
1355       (receiver_klass.not_null() && !receiver_klass->is_subtype_of(receiver_limit())))
1356     // given type is not limited to the receiver type
1357     // note that a null receiver can match any reference value, for a static method
1358     return methodHandle();
1359 
1360   if (!(decode_flags & MethodHandles::_dmf_does_dispatch)) {
1361     // pre-dispatched or static method (null receiver is OK for static)
1362     return m;
1363 
1364   } else if (receiver_klass.is_null()) {
1365     // null receiver value; cannot dispatch
1366     return methodHandle();
1367 
1368   } else if (!(decode_flags & MethodHandles::_dmf_from_interface)) {
1369     // perform virtual dispatch
1370     int vtable_index = m->vtable_index();
1371     guarantee(vtable_index >= 0, "valid vtable index");
1372 
1373     // receiver_klass might be an arrayKlassOop but all vtables start at
1374     // the same place. The cast is to avoid virtual call and assertion.
1375     // See also LinkResolver::runtime_resolve_virtual_method.
1376     instanceKlass* inst = (instanceKlass*)Klass::cast(receiver_klass());
1377     DEBUG_ONLY(inst->verify_vtable_index(vtable_index));
1378     methodOop m_oop = inst->method_at_vtable(vtable_index);
1379     return methodHandle(THREAD, m_oop);
1380 
1381   } else {
1382     // perform interface dispatch
1383     int itable_index = klassItable::compute_itable_index(m());
1384     guarantee(itable_index >= 0, "valid itable index");
1385     instanceKlass* inst = instanceKlass::cast(receiver_klass());
1386     methodOop m_oop = inst->method_at_itable(m->method_holder(), itable_index, THREAD);
1387     return methodHandle(THREAD, m_oop);
1388   }
1389 }
1390 
1391 void MethodHandles::verify_DirectMethodHandle(Handle mh, methodHandle m, TRAPS) {
1392   // Verify type.
1393   Handle mtype(THREAD, java_dyn_MethodHandle::type(mh()));
1394   verify_method_type(m, mtype, false, KlassHandle(), CHECK);
1395 
1396   // Verify vmslots.
1397   if (java_dyn_MethodHandle::vmslots(mh()) != m->size_of_parameters()) {
1398     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in DMH");
1399   }
1400 }
1401 
1402 void MethodHandles::init_DirectMethodHandle(Handle mh, methodHandle m, bool do_dispatch, TRAPS) {
1403   // Check arguments.
1404   if (mh.is_null() || m.is_null() ||
1405       (!do_dispatch && m->is_abstract())) {
1406     THROW(vmSymbols::java_lang_InternalError());
1407   }
1408 
1409   java_dyn_MethodHandle::init_vmslots(mh());
1410 
1411   if (VerifyMethodHandles) {
1412     // The privileged code which invokes this routine should not make
1413     // a mistake about types, but it's better to verify.
1414     verify_DirectMethodHandle(mh, m, CHECK);
1415   }
1416 
1417   // Finally, after safety checks are done, link to the target method.
1418   // We will follow the same path as the latter part of
1419   // InterpreterRuntime::resolve_invoke(), which first finds the method
1420   // and then decides how to populate the constant pool cache entry
1421   // that links the interpreter calls to the method.  We need the same
1422   // bits, and will use the same calling sequence code.
1423 
1424   int vmindex = methodOopDesc::garbage_vtable_index;
1425   oop vmtarget = NULL;
1426 
1427   instanceKlass::cast(m->method_holder())->link_class(CHECK);
1428 
1429   MethodHandleEntry* me = NULL;
1430   if (do_dispatch && Klass::cast(m->method_holder())->is_interface()) {
1431     // We are simulating an invokeinterface instruction.
1432     // (We might also be simulating an invokevirtual on a miranda method,
1433     // but it is safe to treat it as an invokeinterface.)
1434     assert(!m->can_be_statically_bound(), "no final methods on interfaces");
1435     vmindex = klassItable::compute_itable_index(m());
1436     assert(vmindex >= 0, "(>=0) == do_dispatch");
1437     // Set up same bits as ConstantPoolCacheEntry::set_interface_call().
1438     vmtarget = m->method_holder(); // the interface
1439     me = MethodHandles::entry(MethodHandles::_invokeinterface_mh);
1440   } else if (!do_dispatch || m->can_be_statically_bound()) {
1441     // We are simulating an invokestatic or invokespecial instruction.
1442     // Set up the method pointer, just like ConstantPoolCacheEntry::set_method().
1443     vmtarget = m();
1444     // this does not help dispatch, but it will make it possible to parse this MH:
1445     vmindex  = methodOopDesc::nonvirtual_vtable_index;
1446     assert(vmindex < 0, "(>=0) == do_dispatch");
1447     if (!m->is_static()) {
1448       me = MethodHandles::entry(MethodHandles::_invokespecial_mh);
1449     } else {
1450       me = MethodHandles::entry(MethodHandles::_invokestatic_mh);
1451       // Part of the semantics of a static call is an initialization barrier.
1452       // For a DMH, it is done now, when the handle is created.
1453       Klass* k = Klass::cast(m->method_holder());
1454       if (k->should_be_initialized()) {
1455         k->initialize(CHECK);
1456       }
1457     }
1458   } else {
1459     // We are simulating an invokevirtual instruction.
1460     // Set up the vtable index, just like ConstantPoolCacheEntry::set_method().
1461     // The key logic is LinkResolver::runtime_resolve_virtual_method.
1462     vmindex  = m->vtable_index();
1463     vmtarget = m->method_holder();
1464     me = MethodHandles::entry(MethodHandles::_invokevirtual_mh);
1465   }
1466 
1467   if (me == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
1468 
1469   sun_dyn_DirectMethodHandle::set_vmtarget(mh(), vmtarget);
1470   sun_dyn_DirectMethodHandle::set_vmindex(mh(),  vmindex);
1471   DEBUG_ONLY(int flags; klassOop rlimit);
1472   assert(MethodHandles::decode_method(mh(), rlimit, flags) == m(),
1473          "properly stored for later decoding");
1474   DEBUG_ONLY(bool actual_do_dispatch = ((flags & _dmf_does_dispatch) != 0));
1475   assert(!(actual_do_dispatch && !do_dispatch),
1476          "do not perform dispatch if !do_dispatch specified");
1477   assert(actual_do_dispatch == (vmindex >= 0), "proper later decoding of do_dispatch");
1478   assert(decode_MethodHandle_stack_pushes(mh()) == 0, "DMH does not move stack");
1479 
1480   // Done!
1481   java_dyn_MethodHandle::set_vmentry(mh(), me);
1482 }
1483 
1484 void MethodHandles::verify_BoundMethodHandle_with_receiver(Handle mh,
1485                                                            methodHandle m,
1486                                                            TRAPS) {
1487   // Verify type.
1488   oop receiver = sun_dyn_BoundMethodHandle::argument(mh());
1489   Handle mtype(THREAD, java_dyn_MethodHandle::type(mh()));
1490   KlassHandle bound_recv_type;
1491   if (receiver != NULL)  bound_recv_type = KlassHandle(THREAD, receiver->klass());
1492   verify_method_type(m, mtype, true, bound_recv_type, CHECK);
1493 
1494   int receiver_pos = m->size_of_parameters() - 1;
1495 
1496   // Verify MH.vmargslot, which should point at the bound receiver.
1497   verify_vmargslot(mh, -1, sun_dyn_BoundMethodHandle::vmargslot(mh()), CHECK);
1498   //verify_vmslots(mh, CHECK);
1499 
1500   // Verify vmslots.
1501   if (java_dyn_MethodHandle::vmslots(mh()) != receiver_pos) {
1502     THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH (receiver)");
1503   }
1504 }
1505 
1506 // Initialize a BMH with a receiver bound directly to a methodOop.
1507 void MethodHandles::init_BoundMethodHandle_with_receiver(Handle mh,
1508                                                          methodHandle original_m,
1509                                                          KlassHandle receiver_limit,
1510                                                          int decode_flags,
1511                                                          TRAPS) {
1512   // Check arguments.
1513   if (mh.is_null() || original_m.is_null()) {
1514     THROW(vmSymbols::java_lang_InternalError());
1515   }
1516 
1517   KlassHandle receiver_klass;
1518   {
1519     oop receiver_oop = sun_dyn_BoundMethodHandle::argument(mh());
1520     if (receiver_oop != NULL)
1521       receiver_klass = KlassHandle(THREAD, receiver_oop->klass());
1522   }
1523   methodHandle m = dispatch_decoded_method(original_m,
1524                                            receiver_limit, decode_flags,
1525                                            receiver_klass,
1526                                            CHECK);
1527   if (m.is_null())      { THROW(vmSymbols::java_lang_InternalError()); }
1528   if (m->is_abstract()) { THROW(vmSymbols::java_lang_AbstractMethodError()); }
1529 
1530   java_dyn_MethodHandle::init_vmslots(mh());
1531 
1532   if (VerifyMethodHandles) {
1533     verify_BoundMethodHandle_with_receiver(mh, m, CHECK);
1534   }
1535 
1536   sun_dyn_BoundMethodHandle::set_vmtarget(mh(), m());
1537 
1538   DEBUG_ONLY(int junk; klassOop junk2);
1539   assert(MethodHandles::decode_method(mh(), junk2, junk) == m(), "properly stored for later decoding");
1540   assert(decode_MethodHandle_stack_pushes(mh()) == 1, "BMH pushes one stack slot");
1541 
1542   // Done!
1543   java_dyn_MethodHandle::set_vmentry(mh(), MethodHandles::entry(MethodHandles::_bound_ref_direct_mh));
1544 }
1545 
1546 void MethodHandles::verify_BoundMethodHandle(Handle mh, Handle target, int argnum,
1547                                              bool direct_to_method, TRAPS) {
1548   Handle ptype_handle(THREAD,
1549                            java_dyn_MethodType::ptype(java_dyn_MethodHandle::type(target()), argnum));
1550   KlassHandle ptype_klass;
1551   BasicType ptype = java_lang_Class::as_BasicType(ptype_handle(), &ptype_klass);
1552   int slots_pushed = type2size[ptype];
1553 
1554   oop argument = sun_dyn_BoundMethodHandle::argument(mh());
1555 
1556   const char* err = NULL;
1557 
1558   switch (ptype) {
1559   case T_OBJECT:
1560     if (argument != NULL)
1561       // we must implicitly convert from the arg type to the outgoing ptype
1562       err = check_argument_type_change(T_OBJECT, argument->klass(), ptype, ptype_klass(), argnum);
1563     break;
1564 
1565   case T_ARRAY: case T_VOID:
1566     assert(false, "array, void do not appear here");
1567   default:
1568     if (ptype != T_INT && !is_subword_type(ptype)) {
1569       err = "unexpected parameter type";
1570       break;
1571     }
1572     // check subrange of Integer.value, if necessary
1573     if (argument == NULL || argument->klass() != SystemDictionary::Integer_klass()) {
1574       err = "bound integer argument must be of type java.lang.Integer";
1575       break;
1576     }
1577     if (ptype != T_INT) {
1578       int value_offset = java_lang_boxing_object::value_offset_in_bytes(T_INT);
1579       jint value = argument->int_field(value_offset);
1580       int vminfo = adapter_unbox_subword_vminfo(ptype);
1581       jint subword = truncate_subword_from_vminfo(value, vminfo);
1582       if (value != subword) {
1583         err = "bound subword value does not fit into the subword type";
1584         break;
1585       }
1586     }
1587     break;
1588   case T_FLOAT:
1589   case T_DOUBLE:
1590   case T_LONG:
1591     {
1592       // we must implicitly convert from the unboxed arg type to the outgoing ptype
1593       BasicType argbox = java_lang_boxing_object::basic_type(argument);
1594       if (argbox != ptype) {
1595         err = check_argument_type_change(T_OBJECT, (argument == NULL
1596                                                     ? SystemDictionary::Object_klass()
1597                                                     : argument->klass()),
1598                                          ptype, ptype_klass(), argnum);
1599         assert(err != NULL, "this must be an error");
1600       }
1601       break;
1602     }
1603   }
1604 
1605   if (err == NULL) {
1606     DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
1607     if (direct_to_method) {
1608       assert(this_pushes == slots_pushed, "BMH pushes one or two stack slots");
1609       assert(slots_pushed <= MethodHandlePushLimit, "");
1610     } else {
1611       int target_pushes = decode_MethodHandle_stack_pushes(target());
1612       assert(this_pushes == slots_pushed + target_pushes, "BMH stack motion must be correct");
1613       // do not blow the stack; use a Java-based adapter if this limit is exceeded
1614       // FIXME
1615       // if (slots_pushed + target_pushes > MethodHandlePushLimit)
1616       //   err = "too many bound parameters";
1617     }
1618   }
1619 
1620   if (err == NULL) {
1621     // Verify the rest of the method type.
1622     err = check_method_type_insertion(java_dyn_MethodHandle::type(mh()),
1623                                       argnum, ptype_handle(),
1624                                       java_dyn_MethodHandle::type(target()));
1625   }
1626 
1627   if (err != NULL) {
1628     THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1629   }
1630 }
1631 
1632 void MethodHandles::init_BoundMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
1633   // Check arguments.
1634   if (mh.is_null() || target.is_null() || !java_dyn_MethodHandle::is_instance(target())) {
1635     THROW(vmSymbols::java_lang_InternalError());
1636   }
1637 
1638   java_dyn_MethodHandle::init_vmslots(mh());
1639 
1640   if (VerifyMethodHandles) {
1641     int insert_after = argnum - 1;
1642     verify_vmargslot(mh, insert_after, sun_dyn_BoundMethodHandle::vmargslot(mh()), CHECK);
1643     verify_vmslots(mh, CHECK);
1644   }
1645 
1646   // Get bound type and required slots.
1647   oop ptype_oop = java_dyn_MethodType::ptype(java_dyn_MethodHandle::type(target()), argnum);
1648   BasicType ptype = java_lang_Class::as_BasicType(ptype_oop);
1649   int slots_pushed = type2size[ptype];
1650 
1651   // If (a) the target is a direct non-dispatched method handle,
1652   // or (b) the target is a dispatched direct method handle and we
1653   // are binding the receiver, cut out the middle-man.
1654   // Do this by decoding the DMH and using its methodOop directly as vmtarget.
1655   bool direct_to_method = false;
1656   if (OptimizeMethodHandles &&
1657       target->klass() == SystemDictionary::DirectMethodHandle_klass() &&
1658       (argnum == 0 || sun_dyn_DirectMethodHandle::vmindex(target()) < 0)) {
1659     int decode_flags = 0; klassOop receiver_limit_oop = NULL;
1660     methodHandle m(THREAD, decode_method(target(), receiver_limit_oop, decode_flags));
1661     if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "DMH failed to decode"); }
1662     DEBUG_ONLY(int m_vmslots = m->size_of_parameters() - slots_pushed); // pos. of 1st arg.
1663     assert(sun_dyn_BoundMethodHandle::vmslots(mh()) == m_vmslots, "type w/ m sig");
1664     if (argnum == 0 && (decode_flags & _dmf_has_receiver) != 0) {
1665       KlassHandle receiver_limit(THREAD, receiver_limit_oop);
1666       init_BoundMethodHandle_with_receiver(mh, m,
1667                                            receiver_limit, decode_flags,
1668                                            CHECK);
1669       return;
1670     }
1671 
1672     // Even if it is not a bound receiver, we still might be able
1673     // to bind another argument and still invoke the methodOop directly.
1674     if (!(decode_flags & _dmf_does_dispatch)) {
1675       direct_to_method = true;
1676       sun_dyn_BoundMethodHandle::set_vmtarget(mh(), m());
1677     }
1678   }
1679   if (!direct_to_method)
1680     sun_dyn_BoundMethodHandle::set_vmtarget(mh(), target());
1681 
1682   if (VerifyMethodHandles) {
1683     verify_BoundMethodHandle(mh, target, argnum, direct_to_method, CHECK);
1684   }
1685 
1686   // Next question:  Is this a ref, int, or long bound value?
1687   MethodHandleEntry* me = NULL;
1688   if (ptype == T_OBJECT) {
1689     if (direct_to_method)  me = MethodHandles::entry(_bound_ref_direct_mh);
1690     else                   me = MethodHandles::entry(_bound_ref_mh);
1691   } else if (slots_pushed == 2) {
1692     if (direct_to_method)  me = MethodHandles::entry(_bound_long_direct_mh);
1693     else                   me = MethodHandles::entry(_bound_long_mh);
1694   } else if (slots_pushed == 1) {
1695     if (direct_to_method)  me = MethodHandles::entry(_bound_int_direct_mh);
1696     else                   me = MethodHandles::entry(_bound_int_mh);
1697   } else {
1698     assert(false, "");
1699   }
1700 
1701   // Done!
1702   java_dyn_MethodHandle::set_vmentry(mh(), me);
1703 }
1704 
1705 static void throw_InternalError_for_bad_conversion(int conversion, const char* err, TRAPS) {
1706   char msg[200];
1707   jio_snprintf(msg, sizeof(msg), "bad adapter (conversion=0x%08x): %s", conversion, err);
1708   THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), msg);
1709 }
1710 
1711 void MethodHandles::verify_AdapterMethodHandle(Handle mh, int argnum, TRAPS) {
1712   jint conversion = sun_dyn_AdapterMethodHandle::conversion(mh());
1713   int  argslot    = sun_dyn_AdapterMethodHandle::vmargslot(mh());
1714 
1715   verify_vmargslot(mh, argnum, argslot, CHECK);
1716   verify_vmslots(mh, CHECK);
1717 
1718   jint conv_op    = adapter_conversion_op(conversion);
1719   if (!conv_op_valid(conv_op)) {
1720     throw_InternalError_for_bad_conversion(conversion, "unknown conversion op", THREAD);
1721     return;
1722   }
1723   EntryKind ek = adapter_entry_kind(conv_op);
1724 
1725   int stack_move = adapter_conversion_stack_move(conversion);
1726   BasicType src  = adapter_conversion_src_type(conversion);
1727   BasicType dest = adapter_conversion_dest_type(conversion);
1728   int vminfo     = adapter_conversion_vminfo(conversion); // should be zero
1729 
1730   Handle argument(THREAD,  sun_dyn_AdapterMethodHandle::argument(mh()));
1731   Handle target(THREAD,    sun_dyn_AdapterMethodHandle::vmtarget(mh()));
1732   Handle src_mtype(THREAD, java_dyn_MethodHandle::type(mh()));
1733   Handle dst_mtype(THREAD, java_dyn_MethodHandle::type(target()));
1734 
1735   const char* err = NULL;
1736 
1737   if (err == NULL) {
1738     // Check that the correct argument is supplied, but only if it is required.
1739     switch (ek) {
1740     case _adapter_check_cast:     // target type of cast
1741     case _adapter_ref_to_prim:    // wrapper type from which to unbox
1742     case _adapter_prim_to_ref:    // wrapper type to box into
1743     case _adapter_collect_args:   // array type to collect into
1744     case _adapter_spread_args:    // array type to spread from
1745       if (!java_lang_Class::is_instance(argument())
1746           || java_lang_Class::is_primitive(argument()))
1747         { err = "adapter requires argument of type java.lang.Class"; break; }
1748       if (ek == _adapter_collect_args ||
1749           ek == _adapter_spread_args) {
1750         // Make sure it is a suitable collection type.  (Array, for now.)
1751         Klass* ak = Klass::cast(java_lang_Class::as_klassOop(argument()));
1752         if (!ak->oop_is_objArray()) {
1753           { err = "adapter requires argument of type java.lang.Class<Object[]>"; break; }
1754         }
1755       }
1756       break;
1757     case _adapter_flyby:
1758     case _adapter_ricochet:
1759       if (!java_dyn_MethodHandle::is_instance(argument()))
1760         { err = "MethodHandle adapter argument required"; break; }
1761       break;
1762     default:
1763       if (argument.not_null())
1764         { err = "adapter has spurious argument"; break; }
1765       break;
1766     }
1767   }
1768 
1769   if (err == NULL) {
1770     // Check that the src/dest types are supplied if needed.
1771     switch (ek) {
1772     case _adapter_check_cast:
1773       if (src != T_OBJECT || dest != T_OBJECT) {
1774         err = "adapter requires object src/dest conversion subfields";
1775       }
1776       break;
1777     case _adapter_prim_to_prim:
1778       if (!is_java_primitive(src) || !is_java_primitive(dest) || src == dest) {
1779         err = "adapter requires primitive src/dest conversion subfields"; break;
1780       }
1781       if ( (src == T_FLOAT || src == T_DOUBLE) && !(dest == T_FLOAT || dest == T_DOUBLE) ||
1782           !(src == T_FLOAT || src == T_DOUBLE) &&  (dest == T_FLOAT || dest == T_DOUBLE)) {
1783         err = "adapter cannot convert beween floating and fixed-point"; break;
1784       }
1785       break;
1786     case _adapter_ref_to_prim:
1787       if (src != T_OBJECT || !is_java_primitive(dest)
1788           || argument() != Klass::cast(SystemDictionary::box_klass(dest))->java_mirror()) {
1789         err = "adapter requires primitive dest conversion subfield"; break;
1790       }
1791       break;
1792     case _adapter_prim_to_ref:
1793       if (!is_java_primitive(src) || dest != T_OBJECT
1794           || argument() != Klass::cast(SystemDictionary::box_klass(src))->java_mirror()) {
1795         err = "adapter requires primitive src conversion subfield"; break;
1796       }
1797       break;
1798     case _adapter_swap_args:
1799     case _adapter_rot_args:
1800       {
1801         if (!src || src != dest) {
1802           err = "adapter requires src/dest conversion subfields for swap"; break;
1803         }
1804         int swap_size = type2size[src];
1805         oop src_mtype  = sun_dyn_AdapterMethodHandle::type(mh());
1806         oop dest_mtype = sun_dyn_AdapterMethodHandle::type(target());
1807         int slot_limit = sun_dyn_AdapterMethodHandle::vmslots(target());
1808         int src_slot   = argslot;
1809         int dest_slot  = vminfo;
1810         bool rotate_up = (src_slot > dest_slot); // upward rotation
1811         int src_arg    = argnum;
1812         int dest_arg   = argument_slot_to_argnum(dest_mtype, dest_slot);
1813         verify_vmargslot(mh, dest_arg, dest_slot, CHECK);
1814         if (!(dest_slot >= src_slot + swap_size) &&
1815             !(src_slot >= dest_slot + swap_size)) {
1816           err = "source, destination slots must be distinct";
1817         } else if (ek == _adapter_swap_args && !(src_slot > dest_slot)) {
1818           err = "source of swap must be deeper in stack";
1819         } else if (ek == _adapter_swap_args) {
1820           err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, dest_arg),
1821                                            java_dyn_MethodType::ptype(dest_mtype, src_arg),
1822                                            dest_arg);
1823         } else if (ek == _adapter_rot_args) {
1824           if (rotate_up) {
1825             assert((src_slot > dest_slot) && (src_arg < dest_arg), "");
1826             // rotate up: [dest_slot..src_slot-ss] --> [dest_slot+ss..src_slot]
1827             // that is:   [src_arg+1..dest_arg] --> [src_arg..dest_arg-1]
1828             for (int i = src_arg+1; i <= dest_arg && err == NULL; i++) {
1829               err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, i),
1830                                                java_dyn_MethodType::ptype(dest_mtype, i-1),
1831                                                i);
1832             }
1833           } else { // rotate down
1834             assert((src_slot < dest_slot) && (src_arg > dest_arg), "");
1835             // rotate down: [src_slot+ss..dest_slot] --> [src_slot..dest_slot-ss]
1836             // that is:     [dest_arg..src_arg-1] --> [dst_arg+1..src_arg]
1837             for (int i = dest_arg; i <= src_arg-1 && err == NULL; i++) {
1838               err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, i),
1839                                                java_dyn_MethodType::ptype(dest_mtype, i+1),
1840                                                i);
1841             }
1842           }
1843         }
1844         if (err == NULL)
1845           err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype, src_arg),
1846                                            java_dyn_MethodType::ptype(dest_mtype, dest_arg),
1847                                            src_arg);
1848       }
1849       break;
1850     case _adapter_collect_args:
1851     case _adapter_spread_args:
1852       {
1853         BasicType coll_type = (ek == _adapter_collect_args) ? dest : src;
1854         BasicType elem_type = (ek == _adapter_collect_args) ? src : dest;
1855         if (coll_type != T_OBJECT || elem_type != T_OBJECT) {
1856           err = "adapter requires src/dest subfields"; break;
1857           // later:
1858           // - consider making coll be a primitive array
1859           // - consider making coll be a heterogeneous collection
1860         }
1861       }
1862       break;
1863     default:
1864       if (src != 0 || dest != 0) {
1865         err = "adapter has spurious src/dest conversion subfields"; break;
1866       }
1867       break;
1868     }
1869   }
1870 
1871   if (err == NULL) {
1872     // Check the stack_move subfield.
1873     // It must always report the net change in stack size, positive or negative.
1874     int slots_pushed = stack_move / stack_move_unit();
1875     switch (ek) {
1876     case _adapter_prim_to_prim:
1877     case _adapter_ref_to_prim:
1878     case _adapter_prim_to_ref:
1879       if (slots_pushed != type2size[dest] - type2size[src]) {
1880         err = "wrong stack motion for primitive conversion";
1881       }
1882       break;
1883     case _adapter_dup_args:
1884       if (slots_pushed <= 0) {
1885         err = "adapter requires conversion subfield slots_pushed > 0";
1886       }
1887       break;
1888     case _adapter_drop_args:
1889       if (slots_pushed >= 0) {
1890         err = "adapter requires conversion subfield slots_pushed < 0";
1891       }
1892       break;
1893     case _adapter_collect_args:
1894       if (slots_pushed > 1) {
1895         err = "adapter requires conversion subfield slots_pushed <= 1";
1896       }
1897       break;
1898     case _adapter_spread_args:
1899       if (slots_pushed < -1) {
1900         err = "adapter requires conversion subfield slots_pushed >= -1";
1901       }
1902       break;
1903     default:
1904       if (stack_move != 0) {
1905         err = "adapter has spurious stack_move conversion subfield";
1906       }
1907       break;
1908     }
1909     if (err == NULL && stack_move != slots_pushed * stack_move_unit()) {
1910       err = "stack_move conversion subfield must be multiple of stack_move_unit";
1911     }
1912   }
1913 
1914   if (err == NULL) {
1915     // Make sure this adapter does not push too deeply.
1916     int slots_pushed = stack_move / stack_move_unit();
1917     int this_vmslots = java_dyn_MethodHandle::vmslots(mh());
1918     int target_vmslots = java_dyn_MethodHandle::vmslots(target());
1919     if (slots_pushed != (target_vmslots - this_vmslots)) {
1920       err = "stack_move inconsistent with previous and current MethodType vmslots";
1921     } else if (slots_pushed > 0)  {
1922       // verify stack_move against MethodHandlePushLimit
1923       int target_pushes = decode_MethodHandle_stack_pushes(target());
1924       // do not blow the stack; use a Java-based adapter if this limit is exceeded
1925       if (slots_pushed + target_pushes > MethodHandlePushLimit) {
1926         err = "adapter pushes too many parameters";
1927       }
1928     }
1929 
1930     // While we're at it, check that the stack motion decoder works:
1931     DEBUG_ONLY(int target_pushes = decode_MethodHandle_stack_pushes(target()));
1932     DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
1933     assert(this_pushes == slots_pushed + target_pushes, "AMH stack motion must be correct");
1934   }
1935 
1936   if (err == NULL && vminfo != 0) {
1937     switch (ek) {
1938       case _adapter_swap_args:
1939       case _adapter_rot_args:
1940         break;                // OK
1941     default:
1942       err = "vminfo subfield is reserved to the JVM";
1943     }
1944   }
1945 
1946   // Do additional ad hoc checks.
1947   if (err == NULL) {
1948     switch (ek) {
1949     case _adapter_retype_only:
1950       err = check_method_type_passthrough(src_mtype(), dst_mtype(), false);
1951       break;
1952 
1953     case _adapter_retype_raw:
1954       err = check_method_type_passthrough(src_mtype(), dst_mtype(), true);
1955       break;
1956 
1957     case _adapter_check_cast:
1958       {
1959         // The actual value being checked must be a reference:
1960         err = check_argument_type_change(java_dyn_MethodType::ptype(src_mtype(), argnum),
1961                                          object_java_mirror(), argnum);
1962         if (err != NULL)  break;
1963 
1964         // The output of the cast must fit with the destination argument:
1965         Handle cast_class = argument;
1966         err = check_method_type_conversion(src_mtype(),
1967                                            argnum, cast_class(),
1968                                            dst_mtype());
1969       }
1970       break;
1971 
1972       // %%% TO DO: continue in remaining cases to verify src/dst_mtype if VerifyMethodHandles
1973     }
1974   }
1975 
1976   if (err != NULL) {
1977     throw_InternalError_for_bad_conversion(conversion, err, THREAD);
1978     return;
1979   }
1980 
1981 }
1982 
1983 void MethodHandles::init_AdapterMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
1984   oop  argument   = sun_dyn_AdapterMethodHandle::argument(mh());
1985   int  argslot    = sun_dyn_AdapterMethodHandle::vmargslot(mh());
1986   jint conversion = sun_dyn_AdapterMethodHandle::conversion(mh());
1987   jint conv_op    = adapter_conversion_op(conversion);
1988 
1989   // adjust the adapter code to the internal EntryKind enumeration:
1990   EntryKind ek_orig = adapter_entry_kind(conv_op);
1991   EntryKind ek_opt  = ek_orig;  // may be optimized
1992 
1993   // Finalize the vmtarget field (Java initialized it to null).
1994   if (!java_dyn_MethodHandle::is_instance(target())) {
1995     throw_InternalError_for_bad_conversion(conversion, "bad target", THREAD);
1996     return;
1997   }
1998   sun_dyn_AdapterMethodHandle::set_vmtarget(mh(), target());
1999 
2000   if (VerifyMethodHandles) {
2001     verify_AdapterMethodHandle(mh, argnum, CHECK);
2002   }
2003 
2004   int stack_move = adapter_conversion_stack_move(conversion);
2005   BasicType src  = adapter_conversion_src_type(conversion);
2006   BasicType dest = adapter_conversion_dest_type(conversion);
2007   int vminfo     = adapter_conversion_vminfo(conversion); // should be zero
2008 
2009   const char* err = NULL;
2010 
2011   // Now it's time to finish the case analysis and pick a MethodHandleEntry.
2012   switch (ek_orig) {
2013   case _adapter_retype_only:
2014   case _adapter_retype_raw:
2015   case _adapter_check_cast:
2016   case _adapter_dup_args:
2017   case _adapter_drop_args:
2018     // these work fine via general case code
2019     break;
2020 
2021   case _adapter_prim_to_prim:
2022     {
2023       // Non-subword cases are {int,float,long,double} -> {int,float,long,double}.
2024       // And, the {float,double} -> {int,long} cases must be handled by Java.
2025       switch (type2size[src] *4+ type2size[dest]) {
2026       case 1 *4+ 1:
2027         assert(src == T_INT || is_subword_type(src), "source is not float");
2028         // Subword-related cases are int -> {boolean,byte,char,short}.
2029         ek_opt = _adapter_opt_i2i;
2030         vminfo = adapter_prim_to_prim_subword_vminfo(dest);
2031         break;
2032       case 2 *4+ 1:
2033         if (src == T_LONG && (dest == T_INT || is_subword_type(dest))) {
2034           ek_opt = _adapter_opt_l2i;
2035           vminfo = adapter_prim_to_prim_subword_vminfo(dest);
2036         } else if (src == T_DOUBLE && dest == T_FLOAT) {
2037           ek_opt = _adapter_opt_d2f;
2038         } else {
2039           assert(false, "");
2040         }
2041         break;
2042       case 1 *4+ 2:
2043         if (src == T_INT && dest == T_LONG) {
2044           ek_opt = _adapter_opt_i2l;
2045         } else if (src == T_FLOAT && dest == T_DOUBLE) {
2046           ek_opt = _adapter_opt_f2d;
2047         } else {
2048           assert(false, "");
2049         }
2050         break;
2051       default:
2052         assert(false, "");
2053         break;
2054       }
2055     }
2056     break;
2057 
2058   case _adapter_ref_to_prim:
2059     {
2060       switch (type2size[dest]) {
2061       case 1:
2062         ek_opt = _adapter_opt_unboxi;
2063         vminfo = adapter_unbox_subword_vminfo(dest);
2064         break;
2065       case 2:
2066         ek_opt = _adapter_opt_unboxl;
2067         break;
2068       default:
2069         assert(false, "");
2070         break;
2071       }
2072     }
2073     break;
2074 
2075   case _adapter_prim_to_ref:
2076     goto throw_not_impl;        // allocates, hence could block
2077 
2078   case _adapter_swap_args:
2079   case _adapter_rot_args:
2080     {
2081       int swap_slots = type2size[src];
2082       int slot_limit = sun_dyn_AdapterMethodHandle::vmslots(mh());
2083       int src_slot   = argslot;
2084       int dest_slot  = vminfo;
2085       int rotate     = (ek_orig == _adapter_swap_args) ? 0 : (src_slot > dest_slot) ? 1 : -1;
2086       switch (swap_slots) {
2087       case 1:
2088         ek_opt = (!rotate    ? _adapter_opt_swap_1 :
2089                   rotate > 0 ? _adapter_opt_rot_1_up : _adapter_opt_rot_1_down);
2090         break;
2091       case 2:
2092         ek_opt = (!rotate    ? _adapter_opt_swap_2 :
2093                   rotate > 0 ? _adapter_opt_rot_2_up : _adapter_opt_rot_2_down);
2094         break;
2095       default:
2096         assert(false, "");
2097         break;
2098       }
2099     }
2100     break;
2101 
2102   case _adapter_collect_args:
2103     goto throw_not_impl;        // allocates, hence could block
2104 
2105   case _adapter_spread_args:
2106     {
2107       // vminfo will be the required length of the array
2108       int slots_pushed = stack_move / stack_move_unit();
2109       int array_size   = slots_pushed + 1;
2110       assert(array_size >= 0, "");
2111       vminfo = array_size;
2112       switch (array_size) {
2113       case 0:   ek_opt = _adapter_opt_spread_0;       break;
2114       case 1:   ek_opt = _adapter_opt_spread_1;       break;
2115       default:  ek_opt = _adapter_opt_spread_more;    break;
2116       }
2117       if ((vminfo & CONV_VMINFO_MASK) != vminfo)
2118         goto throw_not_impl;    // overflow
2119     }
2120     break;
2121 
2122   case _adapter_flyby:
2123   case _adapter_ricochet:
2124     goto throw_not_impl;        // runs Java code, hence could block
2125 
2126   default:
2127     // should have failed much earlier; must be a missing case here
2128     assert(false, "incomplete switch");
2129     // and fall through:
2130 
2131   throw_not_impl:
2132     // FIXME: these adapters are NYI
2133     err = "adapter not yet implemented in the JVM";
2134     break;
2135   }
2136 
2137   if (err != NULL) {
2138     throw_InternalError_for_bad_conversion(conversion, err, THREAD);
2139     return;
2140   }
2141 
2142   // Rebuild the conversion value; maybe parts of it were changed.
2143   jint new_conversion = adapter_conversion(conv_op, src, dest, stack_move, vminfo);
2144 
2145   // Finalize the conversion field.  (Note that it is final to Java code.)
2146   sun_dyn_AdapterMethodHandle::set_conversion(mh(), new_conversion);
2147 
2148   // Done!
2149   java_dyn_MethodHandle::set_vmentry(mh(), entry(ek_opt));
2150 
2151   // There should be enough memory barriers on exit from native methods
2152   // to ensure that the MH is fully initialized to all threads before
2153   // Java code can publish it in global data structures.
2154 }
2155 
2156 //
2157 // Here are the native methods on sun.dyn.MethodHandleImpl.
2158 // They are the private interface between this JVM and the HotSpot-specific
2159 // Java code that implements JSR 292 method handles.
2160 //
2161 // Note:  We use a JVM_ENTRY macro to define each of these, for this is the way
2162 // that intrinsic (non-JNI) native methods are defined in HotSpot.
2163 //
2164 
2165 // direct method handles for invokestatic or invokespecial
2166 // void init(DirectMethodHandle self, MemberName ref, boolean doDispatch, Class<?> caller);
2167 JVM_ENTRY(void, MHI_init_DMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2168                              jobject target_jh, jboolean do_dispatch, jobject caller_jh)) {
2169   ResourceMark rm;              // for error messages
2170 
2171   // This is the guy we are initializing:
2172   if (mh_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2173   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2174 
2175   // Early returns out of this method leave the DMH in an unfinished state.
2176   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2177 
2178   // which method are we really talking about?
2179   if (target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2180   oop target_oop = JNIHandles::resolve_non_null(target_jh);
2181   if (sun_dyn_MemberName::is_instance(target_oop) &&
2182       sun_dyn_MemberName::vmindex(target_oop) == VM_INDEX_UNINITIALIZED) {
2183     Handle mname(THREAD, target_oop);
2184     MethodHandles::resolve_MemberName(mname, CHECK);
2185     target_oop = mname(); // in case of GC
2186   }
2187 
2188   int decode_flags = 0; klassOop receiver_limit = NULL;
2189   methodHandle m(THREAD,
2190                  MethodHandles::decode_method(target_oop,
2191                                               receiver_limit, decode_flags));
2192   if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "no such method"); }
2193 
2194   // The trusted Java code that calls this method should already have performed
2195   // access checks on behalf of the given caller.  But, we can verify this.
2196   if (VerifyMethodHandles && caller_jh != NULL) {
2197     KlassHandle caller(THREAD, java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(caller_jh)));
2198     // If this were a bytecode, the first access check would be against
2199     // the "reference class" mentioned in the CONSTANT_Methodref.
2200     // We don't know at this point which class that was, and if we
2201     // check against m.method_holder we might get the wrong answer.
2202     // So we just make sure to handle this check when the resolution
2203     // happens, when we call resolve_MemberName.
2204     //
2205     // (A public class can inherit public members from private supers,
2206     // and it would be wrong to check access against the private super
2207     // if the original symbolic reference was against the public class.)
2208     //
2209     // If there were a bytecode, the next step would be to lookup the method
2210     // in the reference class, then then check the method's access bits.
2211     // Emulate LinkResolver::check_method_accessability.
2212     klassOop resolved_klass = m->method_holder();
2213     if (!Reflection::verify_field_access(caller->as_klassOop(),
2214                                          resolved_klass, resolved_klass,
2215                                          m->access_flags(),
2216                                          true)) {
2217       // %%% following cutout belongs in Reflection::verify_field_access?
2218       bool same_pm = Reflection::is_same_package_member(caller->as_klassOop(),
2219                                                         resolved_klass, THREAD);
2220       if (!same_pm) {
2221         THROW_MSG(vmSymbols::java_lang_InternalError(), m->name_and_sig_as_C_string());
2222       }
2223     }
2224   }
2225 
2226   MethodHandles::init_DirectMethodHandle(mh, m, (do_dispatch != JNI_FALSE), CHECK);
2227 }
2228 JVM_END
2229 
2230 // bound method handles
2231 JVM_ENTRY(void, MHI_init_BMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2232                              jobject target_jh, int argnum)) {
2233   ResourceMark rm;              // for error messages
2234 
2235   // This is the guy we are initializing:
2236   if (mh_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2237   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2238 
2239   // Early returns out of this method leave the BMH in an unfinished state.
2240   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2241 
2242   if (target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2243   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
2244 
2245   if (!java_dyn_MethodHandle::is_instance(target())) {
2246     // Target object is a reflective method.  (%%% Do we need this alternate path?)
2247     Untested("init_BMH of non-MH");
2248     if (argnum != 0) { THROW(vmSymbols::java_lang_InternalError()); }
2249     int decode_flags = 0; klassOop receiver_limit_oop = NULL;
2250     methodHandle m(THREAD,
2251                    MethodHandles::decode_method(target(),
2252                                                 receiver_limit_oop,
2253                                                 decode_flags));
2254     KlassHandle receiver_limit(THREAD, receiver_limit_oop);
2255     MethodHandles::init_BoundMethodHandle_with_receiver(mh, m,
2256                                                        receiver_limit,
2257                                                        decode_flags,
2258                                                        CHECK);
2259     return;
2260   }
2261 
2262   // Build a BMH on top of a DMH or another BMH:
2263   MethodHandles::init_BoundMethodHandle(mh, target, argnum, CHECK);
2264 }
2265 JVM_END
2266 
2267 // adapter method handles
2268 JVM_ENTRY(void, MHI_init_AMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2269                              jobject target_jh, int argnum)) {
2270   // This is the guy we are initializing:
2271   if (mh_jh == NULL || target_jh == NULL) {
2272     THROW(vmSymbols::java_lang_InternalError());
2273   }
2274   Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2275   Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
2276 
2277   // Early returns out of this method leave the AMH in an unfinished state.
2278   assert(java_dyn_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2279 
2280   MethodHandles::init_AdapterMethodHandle(mh, target, argnum, CHECK);
2281 }
2282 JVM_END
2283 
2284 // method type forms
2285 JVM_ENTRY(void, MHI_init_MT(JNIEnv *env, jobject igcls, jobject erased_jh)) {
2286   if (erased_jh == NULL)  return;
2287   if (TraceMethodHandles) {
2288     tty->print("creating MethodType form ");
2289     if (WizardMode || Verbose) {   // Warning: this calls Java code on the MH!
2290       // call Object.toString()
2291       symbolOop name = vmSymbols::toString_name(), sig = vmSymbols::void_string_signature();
2292       JavaCallArguments args(Handle(THREAD, JNIHandles::resolve_non_null(erased_jh)));
2293       JavaValue result(T_OBJECT);
2294       JavaCalls::call_virtual(&result, SystemDictionary::Object_klass(), name, sig,
2295                               &args, CHECK);
2296       Handle str(THREAD, (oop)result.get_jobject());
2297       java_lang_String::print(str, tty);
2298     }
2299     tty->cr();
2300   }
2301 }
2302 JVM_END
2303 
2304 // debugging and reflection
2305 JVM_ENTRY(jobject, MHI_getTarget(JNIEnv *env, jobject igcls, jobject mh_jh, jint format)) {
2306   Handle mh(THREAD, JNIHandles::resolve(mh_jh));
2307   if (!java_dyn_MethodHandle::is_instance(mh())) {
2308     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
2309   }
2310   oop target = MethodHandles::encode_target(mh, format, CHECK_NULL);
2311   return JNIHandles::make_local(THREAD, target);
2312 }
2313 JVM_END
2314 
2315 JVM_ENTRY(jint, MHI_getConstant(JNIEnv *env, jobject igcls, jint which)) {
2316   switch (which) {
2317   case MethodHandles::GC_JVM_PUSH_LIMIT:
2318     guarantee(MethodHandlePushLimit >= 2 && MethodHandlePushLimit <= 0xFF,
2319               "MethodHandlePushLimit parameter must be in valid range");
2320     return MethodHandlePushLimit;
2321   case MethodHandles::GC_JVM_STACK_MOVE_UNIT:
2322     // return number of words per slot, signed according to stack direction
2323     return MethodHandles::stack_move_unit();
2324   case MethodHandles::GC_CONV_OP_IMPLEMENTED_MASK:
2325     return MethodHandles::adapter_conversion_ops_supported_mask();
2326   }
2327   return 0;
2328 }
2329 JVM_END
2330 
2331 #ifndef PRODUCT
2332 #define EACH_NAMED_CON(template) \
2333     template(MethodHandles,GC_JVM_PUSH_LIMIT) \
2334     template(MethodHandles,GC_JVM_STACK_MOVE_UNIT) \
2335     template(MethodHandles,ETF_HANDLE_OR_METHOD_NAME) \
2336     template(MethodHandles,ETF_DIRECT_HANDLE) \
2337     template(MethodHandles,ETF_METHOD_NAME) \
2338     template(MethodHandles,ETF_REFLECT_METHOD) \
2339     template(sun_dyn_MemberName,MN_IS_METHOD) \
2340     template(sun_dyn_MemberName,MN_IS_CONSTRUCTOR) \
2341     template(sun_dyn_MemberName,MN_IS_FIELD) \
2342     template(sun_dyn_MemberName,MN_IS_TYPE) \
2343     template(sun_dyn_MemberName,MN_SEARCH_SUPERCLASSES) \
2344     template(sun_dyn_MemberName,MN_SEARCH_INTERFACES) \
2345     template(sun_dyn_MemberName,VM_INDEX_UNINITIALIZED) \
2346     template(sun_dyn_AdapterMethodHandle,OP_RETYPE_ONLY) \
2347     template(sun_dyn_AdapterMethodHandle,OP_RETYPE_RAW) \
2348     template(sun_dyn_AdapterMethodHandle,OP_CHECK_CAST) \
2349     template(sun_dyn_AdapterMethodHandle,OP_PRIM_TO_PRIM) \
2350     template(sun_dyn_AdapterMethodHandle,OP_REF_TO_PRIM) \
2351     template(sun_dyn_AdapterMethodHandle,OP_PRIM_TO_REF) \
2352     template(sun_dyn_AdapterMethodHandle,OP_SWAP_ARGS) \
2353     template(sun_dyn_AdapterMethodHandle,OP_ROT_ARGS) \
2354     template(sun_dyn_AdapterMethodHandle,OP_DUP_ARGS) \
2355     template(sun_dyn_AdapterMethodHandle,OP_DROP_ARGS) \
2356     template(sun_dyn_AdapterMethodHandle,OP_COLLECT_ARGS) \
2357     template(sun_dyn_AdapterMethodHandle,OP_SPREAD_ARGS) \
2358     template(sun_dyn_AdapterMethodHandle,OP_FLYBY) \
2359     template(sun_dyn_AdapterMethodHandle,OP_RICOCHET) \
2360     template(sun_dyn_AdapterMethodHandle,CONV_OP_LIMIT) \
2361     template(sun_dyn_AdapterMethodHandle,CONV_OP_MASK) \
2362     template(sun_dyn_AdapterMethodHandle,CONV_VMINFO_MASK) \
2363     template(sun_dyn_AdapterMethodHandle,CONV_VMINFO_SHIFT) \
2364     template(sun_dyn_AdapterMethodHandle,CONV_OP_SHIFT) \
2365     template(sun_dyn_AdapterMethodHandle,CONV_DEST_TYPE_SHIFT) \
2366     template(sun_dyn_AdapterMethodHandle,CONV_SRC_TYPE_SHIFT) \
2367     template(sun_dyn_AdapterMethodHandle,CONV_STACK_MOVE_SHIFT) \
2368     template(sun_dyn_AdapterMethodHandle,CONV_STACK_MOVE_MASK) \
2369     /*end*/
2370 
2371 #define ONE_PLUS(scope,value) 1+
2372 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS) 0;
2373 #define VALUE_COMMA(scope,value) scope::value,
2374 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA) 0 };
2375 #define STRING_NULL(scope,value) #value "\0"
2376 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL) };
2377 
2378 #undef ONE_PLUS
2379 #undef VALUE_COMMA
2380 #undef STRING_NULL
2381 #undef EACH_NAMED_CON
2382 #endif
2383 
2384 JVM_ENTRY(jint, MHI_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
2385 #ifndef PRODUCT
2386   if (which >= 0 && which < con_value_count) {
2387     int con = con_values[which];
2388     objArrayOop box = (objArrayOop) JNIHandles::resolve(box_jh);
2389     if (box != NULL && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
2390       const char* str = &con_names[0];
2391       for (int i = 0; i < which; i++)
2392         str += strlen(str) + 1;   // skip name and null
2393       oop name = java_lang_String::create_oop_from_str(str, CHECK_0);
2394       box->obj_at_put(0, name);
2395     }
2396     return con;
2397   }
2398 #endif
2399   return 0;
2400 }
2401 JVM_END
2402 
2403 // void init(MemberName self, AccessibleObject ref)
2404 JVM_ENTRY(void, MHI_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
2405   if (mname_jh == NULL || target_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2406   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2407   oop target_oop = JNIHandles::resolve_non_null(target_jh);
2408   MethodHandles::init_MemberName(mname(), target_oop);
2409 }
2410 JVM_END
2411 
2412 // void expand(MemberName self)
2413 JVM_ENTRY(void, MHI_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
2414   if (mname_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2415   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2416   MethodHandles::expand_MemberName(mname, 0, CHECK);
2417 }
2418 JVM_END
2419 
2420 // void resolve(MemberName self, Class<?> caller)
2421 JVM_ENTRY(void, MHI_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
2422   if (mname_jh == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
2423   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2424 
2425   // The trusted Java code that calls this method should already have performed
2426   // access checks on behalf of the given caller.  But, we can verify this.
2427   if (VerifyMethodHandles && caller_jh != NULL) {
2428     klassOop reference_klass = java_lang_Class::as_klassOop(sun_dyn_MemberName::clazz(mname()));
2429     if (reference_klass != NULL) {
2430       // Emulate LinkResolver::check_klass_accessability.
2431       klassOop caller = java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(caller_jh));
2432       if (!Reflection::verify_class_access(caller,
2433                                            reference_klass,
2434                                            true)) {
2435         THROW_MSG(vmSymbols::java_lang_InternalError(), Klass::cast(reference_klass)->external_name());
2436       }
2437     }
2438   }
2439 
2440   MethodHandles::resolve_MemberName(mname, CHECK);
2441 }
2442 JVM_END
2443 
2444 //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
2445 //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
2446 JVM_ENTRY(jint, MHI_getMembers(JNIEnv *env, jobject igcls,
2447                                jclass clazz_jh, jstring name_jh, jstring sig_jh,
2448                                int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
2449   if (clazz_jh == NULL || results_jh == NULL)  return -1;
2450   klassOop k_oop = java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(clazz_jh));
2451 
2452   objArrayOop results = (objArrayOop) JNIHandles::resolve(results_jh);
2453   if (results == NULL || !results->is_objArray())       return -1;
2454 
2455   symbolOop name = NULL, sig = NULL;
2456   if (name_jh != NULL) {
2457     name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
2458     if (name == NULL)  return 0; // a match is not possible
2459   }
2460   if (sig_jh != NULL) {
2461     sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
2462     if (sig == NULL)  return 0; // a match is not possible
2463   }
2464 
2465   klassOop caller = NULL;
2466   if (caller_jh != NULL) {
2467     oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
2468     if (!java_lang_Class::is_instance(caller_oop))  return -1;
2469     caller = java_lang_Class::as_klassOop(caller_oop);
2470   }
2471 
2472   if (name != NULL && sig != NULL && results != NULL) {
2473     // try a direct resolve
2474     // %%% TO DO
2475   }
2476 
2477   int res = MethodHandles::find_MemberNames(k_oop, name, sig, mflags,
2478                                             caller, skip, results);
2479   // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
2480   return res;
2481 }
2482 JVM_END
2483 
2484 JVM_ENTRY(void, MHI_registerBootstrap(JNIEnv *env, jobject igcls, jclass caller_jh, jobject bsm_jh)) {
2485   instanceKlassHandle ik = MethodHandles::resolve_instance_klass(caller_jh, THREAD);
2486   if (!AllowTransitionalJSR292) {
2487     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
2488               "registerBootstrapMethod is only supported in JSR 292 EDR");
2489   }
2490   ik->link_class(CHECK);
2491   if (!java_dyn_MethodHandle::is_instance(JNIHandles::resolve(bsm_jh))) {
2492     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "method handle");
2493   }
2494   const char* err = NULL;
2495   if (ik->is_initialized() || ik->is_in_error_state()) {
2496     err = "too late: class is already initialized";
2497   } else {
2498     ObjectLocker ol(ik, THREAD);  // note:  this should be a recursive lock
2499     if (ik->is_not_initialized() ||
2500         (ik->is_being_initialized() && ik->is_reentrant_initialization(THREAD))) {
2501       if (ik->bootstrap_method() != NULL) {
2502         err = "class is already equipped with a bootstrap method";
2503       } else {
2504         ik->set_bootstrap_method(JNIHandles::resolve_non_null(bsm_jh));
2505         err = NULL;
2506       }
2507     } else {
2508       err = "class is already initialized";
2509       if (ik->is_being_initialized())
2510         err = "class is already being initialized in a different thread";
2511     }
2512   }
2513   if (err != NULL) {
2514     THROW_MSG(vmSymbols::java_lang_IllegalStateException(), err);
2515   }
2516 }
2517 JVM_END
2518 
2519 JVM_ENTRY(jobject, MHI_getBootstrap(JNIEnv *env, jobject igcls, jclass caller_jh)) {
2520   instanceKlassHandle ik = MethodHandles::resolve_instance_klass(caller_jh, THREAD);
2521   return JNIHandles::make_local(THREAD, ik->bootstrap_method());
2522 }
2523 JVM_END
2524 
2525 JVM_ENTRY(void, MHI_setCallSiteTarget(JNIEnv *env, jobject igcls, jobject site_jh, jobject target_jh)) {
2526   // No special action required, yet.
2527   oop site_oop = JNIHandles::resolve(site_jh);
2528   if (!java_dyn_CallSite::is_instance(site_oop))
2529     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "not a CallSite");
2530   java_dyn_CallSite::set_target(site_oop, JNIHandles::resolve(target_jh));
2531 }
2532 JVM_END
2533 
2534 
2535 /// JVM_RegisterMethodHandleMethods
2536 
2537 #define ADR "J"
2538 
2539 #define LANG "Ljava/lang/"
2540 #define JDYN "Ljava/dyn/"
2541 #define IDYN "Lsun/dyn/"
2542 
2543 #define OBJ   LANG"Object;"
2544 #define CLS   LANG"Class;"
2545 #define STRG  LANG"String;"
2546 #define CST   JDYN"CallSite;"
2547 #define MT    JDYN"MethodType;"
2548 #define MH    JDYN"MethodHandle;"
2549 #define MHI   IDYN"MethodHandleImpl;"
2550 #define MEM   IDYN"MemberName;"
2551 #define AMH   IDYN"AdapterMethodHandle;"
2552 #define BMH   IDYN"BoundMethodHandle;"
2553 #define DMH   IDYN"DirectMethodHandle;"
2554 
2555 #define CC (char*)  /*cast a literal from (const char*)*/
2556 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
2557 
2558 // These are the native methods on sun.dyn.MethodHandleNatives.
2559 static JNINativeMethod methods[] = {
2560   // void init(MemberName self, AccessibleObject ref)
2561   {CC"init",                    CC"("AMH""MH"I)V",              FN_PTR(MHI_init_AMH)},
2562   {CC"init",                    CC"("BMH""OBJ"I)V",             FN_PTR(MHI_init_BMH)},
2563   {CC"init",                    CC"("DMH""OBJ"Z"CLS")V",        FN_PTR(MHI_init_DMH)},
2564   {CC"init",                    CC"("MT")V",                    FN_PTR(MHI_init_MT)},
2565   {CC"init",                    CC"("MEM""OBJ")V",              FN_PTR(MHI_init_Mem)},
2566   {CC"expand",                  CC"("MEM")V",                   FN_PTR(MHI_expand_Mem)},
2567   {CC"resolve",                 CC"("MEM""CLS")V",              FN_PTR(MHI_resolve_Mem)},
2568   {CC"getTarget",               CC"("MH"I)"OBJ,                 FN_PTR(MHI_getTarget)},
2569   {CC"getConstant",             CC"(I)I",                       FN_PTR(MHI_getConstant)},
2570   //  static native int getNamedCon(int which, Object[] name)
2571   {CC"getNamedCon",             CC"(I["OBJ")I",                 FN_PTR(MHI_getNamedCon)},
2572   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
2573   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
2574   {CC"getMembers",              CC"("CLS""STRG""STRG"I"CLS"I["MEM")I",  FN_PTR(MHI_getMembers)}
2575 };
2576 
2577 // More entry points specifically for EnableInvokeDynamic.
2578 static JNINativeMethod methods2[] = {
2579   {CC"registerBootstrap",       CC"("CLS MH")V",                FN_PTR(MHI_registerBootstrap)},
2580   {CC"getBootstrap",            CC"("CLS")"MH,                  FN_PTR(MHI_getBootstrap)},
2581   {CC"setCallSiteTarget",       CC"("CST MH")V",                FN_PTR(MHI_setCallSiteTarget)}
2582 };
2583 
2584 
2585 // This one function is exported, used by NativeLookup.
2586 
2587 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
2588   assert(MethodHandles::spot_check_entry_names(), "entry enum is OK");
2589 
2590   // note: this explicit warning-producing stuff will be replaced by auto-detection of the JSR 292 classes
2591 
2592   if (!EnableMethodHandles) {
2593     warning("JSR 292 method handles are disabled in this JVM.  Use -XX:+UnlockExperimentalVMOptions -XX:+EnableMethodHandles to enable.");
2594     return;  // bind nothing
2595   }
2596 
2597   bool enable_MH = true;
2598 
2599   {
2600     ThreadToNativeFromVM ttnfv(thread);
2601 
2602     int status = env->RegisterNatives(MHN_class, methods, sizeof(methods)/sizeof(JNINativeMethod));
2603     if (env->ExceptionOccurred()) {
2604       MethodHandles::set_enabled(false);
2605       warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
2606       enable_MH = false;
2607       env->ExceptionClear();
2608     }
2609   }
2610 
2611   if (enable_MH) {
2612     KlassHandle MHI_klass = SystemDictionaryHandles::MethodHandleImpl_klass();
2613     if (MHI_klass.not_null()) {
2614       symbolHandle raiseException_name = oopFactory::new_symbol_handle("raiseException", CHECK);
2615       symbolHandle raiseException_sig  = oopFactory::new_symbol_handle("(ILjava/lang/Object;Ljava/lang/Object;)V", CHECK);
2616       methodOop raiseException_method  = instanceKlass::cast(MHI_klass->as_klassOop())
2617                     ->find_method(raiseException_name(), raiseException_sig());
2618       if (raiseException_method != NULL && raiseException_method->is_static()) {
2619         MethodHandles::set_raise_exception_method(raiseException_method);
2620       } else {
2621         warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
2622         enable_MH = false;
2623       }
2624     }
2625   }
2626 
2627   if (enable_MH) {
2628     MethodHandles::set_enabled(true);
2629   }
2630 
2631   if (!EnableInvokeDynamic) {
2632     warning("JSR 292 invokedynamic is disabled in this JVM.  Use -XX:+UnlockExperimentalVMOptions -XX:+EnableInvokeDynamic to enable.");
2633     return;  // bind nothing
2634   }
2635 
2636   {
2637     ThreadToNativeFromVM ttnfv(thread);
2638 
2639     int status = env->RegisterNatives(MHN_class, methods2, sizeof(methods2)/sizeof(JNINativeMethod));
2640     if (env->ExceptionOccurred()) {
2641       MethodHandles::set_enabled(false);
2642       warning("JSR 292 method handle code is mismatched to this JVM.  Disabling support.");
2643       env->ExceptionClear();
2644     } else {
2645       MethodHandles::set_enabled(true);
2646     }
2647   }
2648 
2649   // Generate method handles adapters if enabled.
2650   if (MethodHandles::enabled()) {
2651     MethodHandles::generate_adapters(CHECK);
2652   }
2653 }
2654 JVM_END