1 /*
   2  * Copyright (c) 1997, 2023, 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 "cds/archiveUtils.hpp"
  27 #include "classfile/defaultMethods.hpp"
  28 #include "classfile/javaClasses.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "classfile/vmClasses.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "compiler/compilationPolicy.hpp"
  33 #include "compiler/compileBroker.hpp"
  34 #include "gc/shared/collectedHeap.inline.hpp"
  35 #include "interpreter/bootstrapInfo.hpp"
  36 #include "interpreter/bytecode.hpp"
  37 #include "interpreter/interpreterRuntime.hpp"
  38 #include "interpreter/linkResolver.hpp"
  39 #include "jvm.h"
  40 #include "logging/log.hpp"
  41 #include "logging/logStream.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "oops/constantPool.inline.hpp"
  44 #include "oops/cpCache.inline.hpp"
  45 #include "oops/instanceKlass.inline.hpp"
  46 #include "oops/klass.inline.hpp"
  47 #include "oops/method.inline.hpp"
  48 #include "oops/objArrayKlass.hpp"
  49 #include "oops/objArrayOop.hpp"
  50 #include "oops/oop.inline.hpp"
  51 #include "oops/resolvedIndyEntry.hpp"
  52 #include "oops/symbolHandle.hpp"
  53 #include "prims/methodHandles.hpp"
  54 #include "runtime/fieldDescriptor.inline.hpp"
  55 #include "runtime/frame.inline.hpp"
  56 #include "runtime/handles.inline.hpp"
  57 #include "runtime/javaThread.hpp"
  58 #include "runtime/reflection.hpp"
  59 #include "runtime/safepointVerifiers.hpp"
  60 #include "runtime/sharedRuntime.hpp"
  61 #include "runtime/signature.hpp"
  62 #include "runtime/vmThread.hpp"
  63 #include "utilities/macros.hpp"
  64 #if INCLUDE_JFR
  65 #include "jfr/jfr.hpp"
  66 #endif
  67 
  68 //------------------------------------------------------------------------------------------------------------------------
  69 // Implementation of CallInfo
  70 
  71 
  72 void CallInfo::set_static(Klass* resolved_klass, const methodHandle& resolved_method, TRAPS) {
  73   int vtable_index = Method::nonvirtual_vtable_index;
  74   set_common(resolved_klass, resolved_method, resolved_method, CallInfo::direct_call, vtable_index, CHECK);
  75 }
  76 
  77 
  78 void CallInfo::set_interface(Klass* resolved_klass,
  79                              const methodHandle& resolved_method,
  80                              const methodHandle& selected_method,
  81                              int itable_index, TRAPS) {
  82   // This is only called for interface methods. If the resolved_method
  83   // comes from java/lang/Object, it can be the subject of a virtual call, so
  84   // we should pick the vtable index from the resolved method.
  85   // In that case, the caller must call set_virtual instead of set_interface.
  86   assert(resolved_method->method_holder()->is_interface(), "");
  87   assert(itable_index == resolved_method()->itable_index(), "");
  88   set_common(resolved_klass, resolved_method, selected_method, CallInfo::itable_call, itable_index, CHECK);
  89 }
  90 
  91 void CallInfo::set_virtual(Klass* resolved_klass,
  92                            const methodHandle& resolved_method,
  93                            const methodHandle& selected_method,
  94                            int vtable_index, TRAPS) {
  95   assert(vtable_index >= 0 || vtable_index == Method::nonvirtual_vtable_index, "valid index");
  96   assert(vtable_index < 0 || !resolved_method->has_vtable_index() || vtable_index == resolved_method->vtable_index(), "");
  97   CallKind kind = (vtable_index >= 0 && !resolved_method->can_be_statically_bound() ? CallInfo::vtable_call : CallInfo::direct_call);
  98   set_common(resolved_klass, resolved_method, selected_method, kind, vtable_index, CHECK);
  99   assert(!resolved_method->is_compiled_lambda_form(), "these must be handled via an invokehandle call");
 100 }
 101 
 102 void CallInfo::set_handle(Klass* resolved_klass,
 103                           const methodHandle& resolved_method,
 104                           Handle resolved_appendix, TRAPS) {
 105   guarantee(resolved_method.not_null(), "resolved method is null");
 106   assert(resolved_method->intrinsic_id() == vmIntrinsics::_invokeBasic ||
 107          resolved_method->is_compiled_lambda_form(),
 108          "linkMethod must return one of these");
 109   int vtable_index = Method::nonvirtual_vtable_index;
 110   assert(!resolved_method->has_vtable_index(), "");
 111   set_common(resolved_klass, resolved_method, resolved_method, CallInfo::direct_call, vtable_index, CHECK);
 112   _resolved_appendix = resolved_appendix;
 113 }
 114 
 115 void CallInfo::set_common(Klass* resolved_klass,
 116                           const methodHandle& resolved_method,
 117                           const methodHandle& selected_method,
 118                           CallKind kind,
 119                           int index,
 120                           TRAPS) {
 121   assert(resolved_method->signature() == selected_method->signature(), "signatures must correspond");
 122   _resolved_klass  = resolved_klass;
 123   _resolved_method = resolved_method;
 124   _selected_method = selected_method;
 125   _call_kind       = kind;
 126   _call_index      = index;
 127   _resolved_appendix = Handle();
 128   DEBUG_ONLY(verify());  // verify before making side effects
 129 
 130   CompilationPolicy::compile_if_required(selected_method, THREAD);
 131 }
 132 
 133 // utility query for unreflecting a method
 134 CallInfo::CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS) {
 135   Klass* resolved_method_holder = resolved_method->method_holder();
 136   if (resolved_klass == nullptr) { // 2nd argument defaults to holder of 1st
 137     resolved_klass = resolved_method_holder;
 138   }
 139   _resolved_klass  = resolved_klass;
 140   _resolved_method = methodHandle(THREAD, resolved_method);
 141   _selected_method = methodHandle(THREAD, resolved_method);
 142   // classify:
 143   CallKind kind = CallInfo::unknown_kind;
 144   int index = resolved_method->vtable_index();
 145   if (resolved_method->can_be_statically_bound()) {
 146     kind = CallInfo::direct_call;
 147   } else if (!resolved_method_holder->is_interface()) {
 148     // Could be an Object method inherited into an interface, but still a vtable call.
 149     kind = CallInfo::vtable_call;
 150   } else if (!resolved_klass->is_interface()) {
 151     // A default or miranda method.  Compute the vtable index.
 152     index = LinkResolver::vtable_index_of_interface_method(resolved_klass, _resolved_method);
 153     assert(index >= 0 , "we should have valid vtable index at this point");
 154 
 155     kind = CallInfo::vtable_call;
 156   } else if (resolved_method->has_vtable_index()) {
 157     // Can occur if an interface redeclares a method of Object.
 158 
 159 #ifdef ASSERT
 160     // Ensure that this is really the case.
 161     Klass* object_klass = vmClasses::Object_klass();
 162     Method * object_resolved_method = object_klass->vtable().method_at(index);
 163     assert(object_resolved_method->name() == resolved_method->name(),
 164       "Object and interface method names should match at vtable index %d, %s != %s",
 165       index, object_resolved_method->name()->as_C_string(), resolved_method->name()->as_C_string());
 166     assert(object_resolved_method->signature() == resolved_method->signature(),
 167       "Object and interface method signatures should match at vtable index %d, %s != %s",
 168       index, object_resolved_method->signature()->as_C_string(), resolved_method->signature()->as_C_string());
 169 #endif // ASSERT
 170 
 171     kind = CallInfo::vtable_call;
 172   } else {
 173     // A regular interface call.
 174     kind = CallInfo::itable_call;
 175     index = resolved_method->itable_index();
 176   }
 177   assert(index == Method::nonvirtual_vtable_index || index >= 0, "bad index %d", index);
 178   _call_kind  = kind;
 179   _call_index = index;
 180   _resolved_appendix = Handle();
 181   // Find or create a ResolvedMethod instance for this Method*
 182   set_resolved_method_name(CHECK);
 183 
 184   DEBUG_ONLY(verify());
 185 }
 186 
 187 void CallInfo::set_resolved_method_name(TRAPS) {
 188   assert(_resolved_method() != nullptr, "Should already have a Method*");
 189   oop rmethod_name = java_lang_invoke_ResolvedMethodName::find_resolved_method(_resolved_method, CHECK);
 190   _resolved_method_name = Handle(THREAD, rmethod_name);
 191 }
 192 
 193 #ifdef ASSERT
 194 void CallInfo::verify() {
 195   switch (call_kind()) {  // the meaning and allowed value of index depends on kind
 196   case CallInfo::direct_call:
 197     if (_call_index == Method::nonvirtual_vtable_index)  break;
 198     // else fall through to check vtable index:
 199   case CallInfo::vtable_call:
 200     assert(resolved_klass()->verify_vtable_index(_call_index), "");
 201     break;
 202   case CallInfo::itable_call:
 203     assert(resolved_method()->method_holder()->verify_itable_index(_call_index), "");
 204     break;
 205   case CallInfo::unknown_kind:
 206     assert(call_kind() != CallInfo::unknown_kind, "CallInfo must be set");
 207     break;
 208   default:
 209     fatal("Unexpected call kind %d", call_kind());
 210   }
 211 }
 212 #endif // ASSERT
 213 
 214 #ifndef PRODUCT
 215 void CallInfo::print() {
 216   ResourceMark rm;
 217   const char* kindstr;
 218   switch (_call_kind) {
 219   case direct_call: kindstr = "direct";  break;
 220   case vtable_call: kindstr = "vtable";  break;
 221   case itable_call: kindstr = "itable";  break;
 222   default         : kindstr = "unknown"; break;
 223   }
 224   tty->print_cr("Call %s@%d %s", kindstr, _call_index,
 225                 _resolved_method.is_null() ? "(none)" : _resolved_method->name_and_sig_as_C_string());
 226 }
 227 #endif
 228 
 229 //------------------------------------------------------------------------------------------------------------------------
 230 // Implementation of LinkInfo
 231 
 232 LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, Bytecodes::Code code, TRAPS) {
 233    // resolve klass
 234   _resolved_klass = pool->klass_ref_at(index, code, CHECK);
 235 
 236   // Get name, signature, and static klass
 237   _name          = pool->name_ref_at(index, code);
 238   _signature     = pool->signature_ref_at(index, code);
 239   _tag           = pool->tag_ref_at(index, code);
 240   _current_klass = pool->pool_holder();
 241   _current_method = current_method;
 242 
 243   // Coming from the constant pool always checks access
 244   _check_access  = true;
 245   _check_loader_constraints = true;
 246 }
 247 
 248 LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, Bytecodes::Code code, TRAPS) {
 249    // resolve klass
 250   _resolved_klass = pool->klass_ref_at(index, code, CHECK);
 251 
 252   // Get name, signature, and static klass
 253   _name          = pool->name_ref_at(index, code);
 254   _signature     = pool->signature_ref_at(index, code);
 255   _tag           = pool->tag_ref_at(index, code);
 256   _current_klass = pool->pool_holder();
 257   _current_method = methodHandle();
 258 
 259   // Coming from the constant pool always checks access
 260   _check_access  = true;
 261   _check_loader_constraints = true;
 262 }
 263 
 264 #ifndef PRODUCT
 265 void LinkInfo::print() {
 266   ResourceMark rm;
 267   tty->print_cr("Link resolved_klass=%s name=%s signature=%s current_klass=%s check_access=%s check_loader_constraints=%s",
 268                 _resolved_klass->name()->as_C_string(),
 269                 _name->as_C_string(),
 270                 _signature->as_C_string(),
 271                 _current_klass == nullptr ? "(none)" : _current_klass->name()->as_C_string(),
 272                 _check_access ? "true" : "false",
 273                 _check_loader_constraints ? "true" : "false");
 274 
 275 }
 276 #endif // PRODUCT
 277 //------------------------------------------------------------------------------------------------------------------------
 278 // Klass resolution
 279 
 280 void LinkResolver::check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS) {
 281   Klass* base_klass = sel_klass;
 282   if (sel_klass->is_objArray_klass()) {
 283     base_klass = ObjArrayKlass::cast(sel_klass)->bottom_klass();
 284   }
 285   // The element type could be a typeArray - we only need the access
 286   // check if it is a reference to another class.
 287   if (!base_klass->is_instance_klass()) {
 288     return;  // no relevant check to do
 289   }
 290 
 291   Reflection::VerifyClassAccessResults vca_result =
 292     Reflection::verify_class_access(ref_klass, InstanceKlass::cast(base_klass), true);
 293   if (vca_result != Reflection::ACCESS_OK) {
 294     ResourceMark rm(THREAD);
 295     char* msg = Reflection::verify_class_access_msg(ref_klass,
 296                                                     InstanceKlass::cast(base_klass),
 297                                                     vca_result);
 298     bool same_module = (base_klass->module() == ref_klass->module());
 299     if (msg == nullptr) {
 300       Exceptions::fthrow(
 301         THREAD_AND_LOCATION,
 302         vmSymbols::java_lang_IllegalAccessError(),
 303         "failed to access class %s from class %s (%s%s%s)",
 304         base_klass->external_name(),
 305         ref_klass->external_name(),
 306         (same_module) ? base_klass->joint_in_module_of_loader(ref_klass) : base_klass->class_in_module_of_loader(),
 307         (same_module) ? "" : "; ",
 308         (same_module) ? "" : ref_klass->class_in_module_of_loader());
 309     } else {
 310       // Use module specific message returned by verify_class_access_msg().
 311       Exceptions::fthrow(
 312         THREAD_AND_LOCATION,
 313         vmSymbols::java_lang_IllegalAccessError(),
 314         "%s", msg);
 315     }
 316   }
 317 }
 318 
 319 //------------------------------------------------------------------------------------------------------------------------
 320 // Method resolution
 321 //
 322 // According to JVM spec. $5.4.3c & $5.4.3d
 323 
 324 // Look up method in klasses, including static methods
 325 // Then look up local default methods
 326 Method* LinkResolver::lookup_method_in_klasses(const LinkInfo& link_info,
 327                                                bool checkpolymorphism,
 328                                                bool in_imethod_resolve) {
 329   NoSafepointVerifier nsv;  // Method* returned may not be reclaimed
 330 
 331   Klass* klass = link_info.resolved_klass();
 332   Symbol* name = link_info.name();
 333   Symbol* signature = link_info.signature();
 334 
 335   // Ignore overpasses so statics can be found during resolution
 336   Method* result = klass->uncached_lookup_method(name, signature, Klass::OverpassLookupMode::skip);
 337 
 338   if (klass->is_array_klass()) {
 339     // Only consider klass and super klass for arrays
 340     return result;
 341   }
 342 
 343   InstanceKlass* ik = InstanceKlass::cast(klass);
 344 
 345   // JDK 8, JVMS 5.4.3.4: Interface method resolution should
 346   // ignore static and non-public methods of java.lang.Object,
 347   // like clone and finalize.
 348   if (in_imethod_resolve &&
 349       result != nullptr &&
 350       ik->is_interface() &&
 351       (result->is_static() || !result->is_public()) &&
 352       result->method_holder() == vmClasses::Object_klass()) {
 353     result = nullptr;
 354   }
 355 
 356   // Before considering default methods, check for an overpass in the
 357   // current class if a method has not been found.
 358   if (result == nullptr) {
 359     result = ik->find_method(name, signature);
 360   }
 361 
 362   if (result == nullptr) {
 363     Array<Method*>* default_methods = ik->default_methods();
 364     if (default_methods != nullptr) {
 365       result = InstanceKlass::find_method(default_methods, name, signature);
 366     }
 367   }
 368 
 369   if (checkpolymorphism && result != nullptr) {
 370     vmIntrinsics::ID iid = result->intrinsic_id();
 371     if (MethodHandles::is_signature_polymorphic(iid)) {
 372       // Do not link directly to these.  The VM must produce a synthetic one using lookup_polymorphic_method.
 373       return nullptr;
 374     }
 375   }
 376   return result;
 377 }
 378 
 379 // returns first instance method
 380 // Looks up method in classes, then looks up local default methods
 381 Method* LinkResolver::lookup_instance_method_in_klasses(Klass* klass,
 382                                                         Symbol* name,
 383                                                         Symbol* signature,
 384                                                         Klass::PrivateLookupMode private_mode) {
 385   Method* result = klass->uncached_lookup_method(name, signature, Klass::OverpassLookupMode::find, private_mode);
 386 
 387   while (result != nullptr && result->is_static() && result->method_holder()->super() != nullptr) {
 388     Klass* super_klass = result->method_holder()->super();
 389     result = super_klass->uncached_lookup_method(name, signature, Klass::OverpassLookupMode::find, private_mode);
 390   }
 391 
 392   if (klass->is_array_klass()) {
 393     // Only consider klass and super klass for arrays
 394     return result;
 395   }
 396 
 397   if (result == nullptr) {
 398     Array<Method*>* default_methods = InstanceKlass::cast(klass)->default_methods();
 399     if (default_methods != nullptr) {
 400       result = InstanceKlass::find_method(default_methods, name, signature);
 401       assert(result == nullptr || !result->is_static(), "static defaults not allowed");
 402     }
 403   }
 404   return result;
 405 }
 406 
 407 int LinkResolver::vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method) {
 408   InstanceKlass* ik = InstanceKlass::cast(klass);
 409   return ik->vtable_index_of_interface_method(resolved_method());
 410 }
 411 
 412 Method* LinkResolver::lookup_method_in_interfaces(const LinkInfo& cp_info) {
 413   InstanceKlass *ik = InstanceKlass::cast(cp_info.resolved_klass());
 414 
 415   // Specify 'true' in order to skip default methods when searching the
 416   // interfaces.  Function lookup_method_in_klasses() already looked for
 417   // the method in the default methods table.
 418   return ik->lookup_method_in_all_interfaces(cp_info.name(), cp_info.signature(), Klass::DefaultsLookupMode::skip);
 419 }
 420 
 421 Method* LinkResolver::lookup_polymorphic_method(const LinkInfo& link_info,
 422                                                 Handle *appendix_result_or_null,
 423                                                 TRAPS) {
 424   ResourceMark rm(THREAD);
 425   Klass* klass = link_info.resolved_klass();
 426   Symbol* name = link_info.name();
 427   Symbol* full_signature = link_info.signature();
 428   LogTarget(Info, methodhandles) lt_mh;
 429 
 430   vmIntrinsics::ID iid = MethodHandles::signature_polymorphic_name_id(name);
 431   log_info(methodhandles)("lookup_polymorphic_method iid=%s %s.%s%s",
 432                           vmIntrinsics::name_at(iid), klass->external_name(),
 433                           name->as_C_string(), full_signature->as_C_string());
 434   if ((klass == vmClasses::MethodHandle_klass() ||
 435        klass == vmClasses::VarHandle_klass()) &&
 436       iid != vmIntrinsics::_none) {
 437     if (MethodHandles::is_signature_polymorphic_intrinsic(iid)) {
 438       // Most of these do not need an up-call to Java to resolve, so can be done anywhere.
 439       // Do not erase last argument type (MemberName) if it is a static linkTo method.
 440       bool keep_last_arg = MethodHandles::is_signature_polymorphic_static(iid);
 441       TempNewSymbol basic_signature =
 442         MethodHandles::lookup_basic_type_signature(full_signature, keep_last_arg);
 443       log_info(methodhandles)("lookup_polymorphic_method %s %s => basic %s",
 444                               name->as_C_string(),
 445                               full_signature->as_C_string(),
 446                               basic_signature->as_C_string());
 447       Method* result = SystemDictionary::find_method_handle_intrinsic(iid,
 448                                                               basic_signature,
 449                                                               CHECK_NULL);
 450       if (result != nullptr) {
 451         assert(result->is_method_handle_intrinsic(), "MH.invokeBasic or MH.linkTo* intrinsic");
 452         assert(result->intrinsic_id() != vmIntrinsics::_invokeGeneric, "wrong place to find this");
 453         assert(basic_signature == result->signature(), "predict the result signature");
 454         if (lt_mh.is_enabled()) {
 455           LogStream ls(lt_mh);
 456           ls.print("lookup_polymorphic_method => intrinsic ");
 457           result->print_on(&ls);
 458         }
 459       }
 460       return result;
 461     } else if (iid == vmIntrinsics::_invokeGeneric
 462                && THREAD->can_call_java()
 463                && appendix_result_or_null != nullptr) {
 464       // This is a method with type-checking semantics.
 465       // We will ask Java code to spin an adapter method for it.
 466       if (!MethodHandles::enabled()) {
 467         // Make sure the Java part of the runtime has been booted up.
 468         Klass* natives = vmClasses::MethodHandleNatives_klass();
 469         if (natives == nullptr || InstanceKlass::cast(natives)->is_not_initialized()) {
 470           SystemDictionary::resolve_or_fail(vmSymbols::java_lang_invoke_MethodHandleNatives(),
 471                                             Handle(),
 472                                             Handle(),
 473                                             true,
 474                                             CHECK_NULL);
 475         }
 476       }
 477 
 478       Handle appendix;
 479       Method* result = SystemDictionary::find_method_handle_invoker(klass,
 480                                                                     name,
 481                                                                     full_signature,
 482                                                                     link_info.current_klass(),
 483                                                                     &appendix,
 484                                                                     CHECK_NULL);
 485       if (lt_mh.is_enabled()) {
 486         LogStream ls(lt_mh);
 487         ls.print("lookup_polymorphic_method => (via Java) ");
 488         result->print_on(&ls);
 489         ls.print("  lookup_polymorphic_method => appendix = ");
 490         appendix.is_null() ? ls.print_cr("(none)") : appendix->print_on(&ls);
 491       }
 492       if (result != nullptr) {
 493 #ifdef ASSERT
 494         ResourceMark rm(THREAD);
 495 
 496         TempNewSymbol basic_signature =
 497           MethodHandles::lookup_basic_type_signature(full_signature);
 498         int actual_size_of_params = result->size_of_parameters();
 499         int expected_size_of_params = ArgumentSizeComputer(basic_signature).size();
 500         // +1 for MethodHandle.this, +1 for trailing MethodType
 501         if (!MethodHandles::is_signature_polymorphic_static(iid))  expected_size_of_params += 1;
 502         if (appendix.not_null())                                   expected_size_of_params += 1;
 503         if (actual_size_of_params != expected_size_of_params) {
 504           tty->print_cr("*** basic_signature=%s", basic_signature->as_C_string());
 505           tty->print_cr("*** result for %s: ", vmIntrinsics::name_at(iid));
 506           result->print();
 507         }
 508         assert(actual_size_of_params == expected_size_of_params,
 509                "%d != %d", actual_size_of_params, expected_size_of_params);
 510 #endif //ASSERT
 511 
 512         assert(appendix_result_or_null != nullptr, "");
 513         (*appendix_result_or_null) = appendix;
 514       }
 515       return result;
 516     }
 517   }
 518   return nullptr;
 519 }
 520 
 521 static void print_nest_host_error_on(stringStream* ss, Klass* ref_klass, Klass* sel_klass) {
 522   assert(ref_klass->is_instance_klass(), "must be");
 523   assert(sel_klass->is_instance_klass(), "must be");
 524   InstanceKlass* ref_ik = InstanceKlass::cast(ref_klass);
 525   InstanceKlass* sel_ik = InstanceKlass::cast(sel_klass);
 526   const char* nest_host_error_1 = ref_ik->nest_host_error();
 527   const char* nest_host_error_2 = sel_ik->nest_host_error();
 528   if (nest_host_error_1 != nullptr || nest_host_error_2 != nullptr) {
 529     ss->print(", (%s%s%s)",
 530               (nest_host_error_1 != nullptr) ? nest_host_error_1 : "",
 531               (nest_host_error_1 != nullptr && nest_host_error_2 != nullptr) ? ", " : "",
 532               (nest_host_error_2 != nullptr) ? nest_host_error_2 : "");
 533   }
 534 }
 535 
 536 void LinkResolver::check_method_accessability(Klass* ref_klass,
 537                                               Klass* resolved_klass,
 538                                               Klass* sel_klass,
 539                                               const methodHandle& sel_method,
 540                                               TRAPS) {
 541 
 542   AccessFlags flags = sel_method->access_flags();
 543 
 544   // Special case:  arrays always override "clone". JVMS 2.15.
 545   // If the resolved klass is an array class, and the declaring class
 546   // is java.lang.Object and the method is "clone", set the flags
 547   // to public.
 548   //
 549   // We'll check for the method name first, as that's most likely
 550   // to be false (so we'll short-circuit out of these tests).
 551   if (sel_method->name() == vmSymbols::clone_name() &&
 552       sel_klass == vmClasses::Object_klass() &&
 553       resolved_klass->is_array_klass()) {
 554     // We need to change "protected" to "public".
 555     assert(flags.is_protected(), "clone not protected?");
 556     jint new_flags = flags.as_int();
 557     new_flags = new_flags & (~JVM_ACC_PROTECTED);
 558     new_flags = new_flags | JVM_ACC_PUBLIC;
 559     flags.set_flags(new_flags);
 560   }
 561 //  assert(extra_arg_result_or_null != nullptr, "must be able to return extra argument");
 562 
 563   bool can_access = Reflection::verify_member_access(ref_klass,
 564                                                      resolved_klass,
 565                                                      sel_klass,
 566                                                      flags,
 567                                                      true, false, CHECK);
 568   // Any existing exceptions that may have been thrown
 569   // have been allowed to propagate.
 570   if (!can_access) {
 571     ResourceMark rm(THREAD);
 572     stringStream ss;
 573     bool same_module = (sel_klass->module() == ref_klass->module());
 574     ss.print("class %s tried to access %s%s%smethod '%s' (%s%s%s)",
 575              ref_klass->external_name(),
 576              sel_method->is_abstract()  ? "abstract "  : "",
 577              sel_method->is_protected() ? "protected " : "",
 578              sel_method->is_private()   ? "private "   : "",
 579              sel_method->external_name(),
 580              (same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
 581              (same_module) ? "" : "; ",
 582              (same_module) ? "" : sel_klass->class_in_module_of_loader()
 583              );
 584 
 585     // For private access see if there was a problem with nest host
 586     // resolution, and if so report that as part of the message.
 587     if (sel_method->is_private()) {
 588       print_nest_host_error_on(&ss, ref_klass, sel_klass);
 589     }
 590 
 591     Exceptions::fthrow(THREAD_AND_LOCATION,
 592                        vmSymbols::java_lang_IllegalAccessError(),
 593                        "%s",
 594                        ss.as_string()
 595                        );
 596     return;
 597   }
 598 }
 599 
 600 void LinkResolver::resolve_continuation_enter(CallInfo& callinfo, TRAPS) {
 601   Klass* resolved_klass = vmClasses::Continuation_klass();
 602   Symbol* method_name = vmSymbols::enter_name();
 603   Symbol* method_signature = vmSymbols::continuationEnter_signature();
 604   Klass*  current_klass = resolved_klass;
 605   LinkInfo link_info(resolved_klass, method_name, method_signature, current_klass);
 606   Method* resolved_method = resolve_method(link_info, Bytecodes::_invokestatic, CHECK);
 607   callinfo.set_static(resolved_klass, methodHandle(THREAD, resolved_method), CHECK);
 608 }
 609 
 610 Method* LinkResolver::resolve_method_statically(Bytecodes::Code code,
 611                                                 const constantPoolHandle& pool, int index, TRAPS) {
 612   // This method is used only
 613   // (1) in C2 from InlineTree::ok_to_inline (via ciMethod::check_call),
 614   // and
 615   // (2) in Bytecode_invoke::static_target
 616   // It appears to fail when applied to an invokeinterface call site.
 617   // FIXME: Remove this method and ciMethod::check_call; refactor to use the other LinkResolver entry points.
 618   // resolve klass
 619   if (code == Bytecodes::_invokedynamic) {
 620     Klass* resolved_klass = vmClasses::MethodHandle_klass();
 621     Symbol* method_name = vmSymbols::invoke_name();
 622     Symbol* method_signature = pool->signature_ref_at(index, code);
 623     Klass*  current_klass = pool->pool_holder();
 624     LinkInfo link_info(resolved_klass, method_name, method_signature, current_klass);
 625     return resolve_method(link_info, code, THREAD);
 626   }
 627 
 628   LinkInfo link_info(pool, index, methodHandle(), code, CHECK_NULL);
 629   Klass* resolved_klass = link_info.resolved_klass();
 630 
 631   if (pool->has_preresolution()
 632       || ((resolved_klass == vmClasses::MethodHandle_klass() || resolved_klass == vmClasses::VarHandle_klass()) &&
 633           MethodHandles::is_signature_polymorphic_name(resolved_klass, link_info.name()))) {
 634     Method* result = ConstantPool::method_at_if_loaded(pool, index);
 635     if (result != nullptr) {
 636       return result;
 637     }
 638   }
 639 
 640   if (code == Bytecodes::_invokeinterface) {
 641     return resolve_interface_method(link_info, code, THREAD);
 642   } else if (code == Bytecodes::_invokevirtual) {
 643     return resolve_method(link_info, code, THREAD);
 644   } else if (!resolved_klass->is_interface()) {
 645     return resolve_method(link_info, code, THREAD);
 646   } else {
 647     return resolve_interface_method(link_info, code, THREAD);
 648   }
 649 }
 650 
 651 // Check and print a loader constraint violation message for method or interface method
 652 void LinkResolver::check_method_loader_constraints(const LinkInfo& link_info,
 653                                                    const methodHandle& resolved_method,
 654                                                    const char* method_type, TRAPS) {
 655   Handle current_loader(THREAD, link_info.current_klass()->class_loader());
 656   Handle resolved_loader(THREAD, resolved_method->method_holder()->class_loader());
 657 
 658   ResourceMark rm(THREAD);
 659   Symbol* failed_type_symbol =
 660     SystemDictionary::check_signature_loaders(link_info.signature(),
 661                                               /*klass_being_linked*/ nullptr, // We are not linking class
 662                                               current_loader,
 663                                               resolved_loader, true);
 664   if (failed_type_symbol != nullptr) {
 665     Klass* current_class = link_info.current_klass();
 666     ClassLoaderData* current_loader_data = current_class->class_loader_data();
 667     assert(current_loader_data != nullptr, "current class has no class loader data");
 668     Klass* resolved_method_class = resolved_method->method_holder();
 669     ClassLoaderData* target_loader_data = resolved_method_class->class_loader_data();
 670     assert(target_loader_data != nullptr, "resolved method's class has no class loader data");
 671 
 672     stringStream ss;
 673     ss.print("loader constraint violation: when resolving %s '", method_type);
 674     Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
 675     ss.print("' the class loader %s of the current class, %s,"
 676              " and the class loader %s for the method's defining class, %s, have"
 677              " different Class objects for the type %s used in the signature (%s; %s)",
 678              current_loader_data->loader_name_and_id(),
 679              current_class->name()->as_C_string(),
 680              target_loader_data->loader_name_and_id(),
 681              resolved_method_class->name()->as_C_string(),
 682              failed_type_symbol->as_C_string(),
 683              current_class->class_in_module_of_loader(false, true),
 684              resolved_method_class->class_in_module_of_loader(false, true));
 685     THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
 686   }
 687 }
 688 
 689 void LinkResolver::check_field_loader_constraints(Symbol* field, Symbol* sig,
 690                                                   Klass* current_klass,
 691                                                   Klass* sel_klass, TRAPS) {
 692   Handle ref_loader(THREAD, current_klass->class_loader());
 693   Handle sel_loader(THREAD, sel_klass->class_loader());
 694 
 695   ResourceMark rm(THREAD);  // needed for check_signature_loaders
 696   Symbol* failed_type_symbol =
 697     SystemDictionary::check_signature_loaders(sig,
 698                                               /*klass_being_linked*/ nullptr, // We are not linking class
 699                                               ref_loader, sel_loader,
 700                                               false);
 701   if (failed_type_symbol != nullptr) {
 702     stringStream ss;
 703     const char* failed_type_name = failed_type_symbol->as_klass_external_name();
 704 
 705     ss.print("loader constraint violation: when resolving field \"%s\" of type %s, "
 706              "the class loader %s of the current class, %s, "
 707              "and the class loader %s for the field's defining %s, %s, "
 708              "have different Class objects for type %s (%s; %s)",
 709              field->as_C_string(),
 710              failed_type_name,
 711              current_klass->class_loader_data()->loader_name_and_id(),
 712              current_klass->external_name(),
 713              sel_klass->class_loader_data()->loader_name_and_id(),
 714              sel_klass->external_kind(),
 715              sel_klass->external_name(),
 716              failed_type_name,
 717              current_klass->class_in_module_of_loader(false, true),
 718              sel_klass->class_in_module_of_loader(false, true));
 719     THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
 720   }
 721 }
 722 
 723 Method* LinkResolver::resolve_method(const LinkInfo& link_info,
 724                                      Bytecodes::Code code, TRAPS) {
 725 
 726   Handle nested_exception;
 727   Klass* resolved_klass = link_info.resolved_klass();
 728 
 729   // 1. For invokevirtual, cannot call an interface method
 730   if (code == Bytecodes::_invokevirtual && resolved_klass->is_interface()) {
 731     ResourceMark rm(THREAD);
 732     char buf[200];
 733     jio_snprintf(buf, sizeof(buf), "Found interface %s, but class was expected",
 734         resolved_klass->external_name());
 735     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
 736   }
 737 
 738   // 2. check constant pool tag for called method - must be JVM_CONSTANT_Methodref
 739   if (!link_info.tag().is_invalid() && !link_info.tag().is_method()) {
 740     ResourceMark rm(THREAD);
 741     stringStream ss;
 742     ss.print("Method '");
 743     Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
 744     ss.print("' must be Methodref constant");
 745     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
 746   }
 747 
 748   // 3. lookup method in resolved klass and its super klasses
 749   methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, true, false));
 750 
 751   // 4. lookup method in all the interfaces implemented by the resolved klass
 752   if (resolved_method.is_null() && !resolved_klass->is_array_klass()) { // not found in the class hierarchy
 753     resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
 754 
 755     if (resolved_method.is_null()) {
 756       // JSR 292:  see if this is an implicitly generated method MethodHandle.linkToVirtual(*...), etc
 757       Method* method = lookup_polymorphic_method(link_info, (Handle*)nullptr, THREAD);
 758       resolved_method = methodHandle(THREAD, method);
 759       if (HAS_PENDING_EXCEPTION) {
 760         nested_exception = Handle(THREAD, PENDING_EXCEPTION);
 761         CLEAR_PENDING_EXCEPTION;
 762       }
 763     }
 764   }
 765 
 766   // 5. method lookup failed
 767   if (resolved_method.is_null()) {
 768     ResourceMark rm(THREAD);
 769     stringStream ss;
 770     ss.print("'");
 771     Method::print_external_name(&ss, resolved_klass, link_info.name(), link_info.signature());
 772     ss.print("'");
 773     THROW_MSG_CAUSE_(vmSymbols::java_lang_NoSuchMethodError(),
 774                      ss.as_string(), nested_exception, nullptr);
 775   }
 776 
 777   // 6. access checks, access checking may be turned off when calling from within the VM.
 778   Klass* current_klass = link_info.current_klass();
 779   if (link_info.check_access()) {
 780     assert(current_klass != nullptr , "current_klass should not be null");
 781 
 782     // check if method can be accessed by the referring class
 783     check_method_accessability(current_klass,
 784                                resolved_klass,
 785                                resolved_method->method_holder(),
 786                                resolved_method,
 787                                CHECK_NULL);
 788   }
 789   if (link_info.check_loader_constraints()) {
 790     // check loader constraints
 791     check_method_loader_constraints(link_info, resolved_method, "method", CHECK_NULL);
 792   }
 793 
 794   return resolved_method();
 795 }
 796 
 797 static void trace_method_resolution(const char* prefix,
 798                                     Klass* klass,
 799                                     Klass* resolved_klass,
 800                                     Method* method,
 801                                     bool logitables,
 802                                     int index = -1) {
 803 #ifndef PRODUCT
 804   ResourceMark rm;
 805   Log(itables) logi;
 806   LogStream lsi(logi.trace());
 807   Log(vtables) logv;
 808   LogStream lsv(logv.trace());
 809   outputStream* st;
 810   if (logitables) {
 811     st = &lsi;
 812   } else {
 813     st = &lsv;
 814   }
 815   st->print("%s%s, compile-time-class:%s, method:%s, method_holder:%s, access_flags: ",
 816             prefix,
 817             (klass == nullptr ? "<null>" : klass->internal_name()),
 818             resolved_klass->internal_name(),
 819             Method::name_and_sig_as_C_string(resolved_klass,
 820                                              method->name(),
 821                                              method->signature()),
 822             method->method_holder()->internal_name());
 823   method->print_linkage_flags(st);
 824   if (index != -1) {
 825     st->print("vtable_index:%d", index);
 826   }
 827   st->cr();
 828 #endif // PRODUCT
 829 }
 830 
 831 // Do linktime resolution of a method in the interface within the context of the specified bytecode.
 832 Method* LinkResolver::resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS) {
 833 
 834   Klass* resolved_klass = link_info.resolved_klass();
 835 
 836   // check if klass is interface
 837   if (!resolved_klass->is_interface()) {
 838     ResourceMark rm(THREAD);
 839     char buf[200];
 840     jio_snprintf(buf, sizeof(buf), "Found class %s, but interface was expected", resolved_klass->external_name());
 841     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
 842   }
 843 
 844   // check constant pool tag for called method - must be JVM_CONSTANT_InterfaceMethodref
 845   if (!link_info.tag().is_invalid() && !link_info.tag().is_interface_method()) {
 846     ResourceMark rm(THREAD);
 847     stringStream ss;
 848     ss.print("Method '");
 849     Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
 850     ss.print("' must be InterfaceMethodref constant");
 851     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
 852   }
 853 
 854   // lookup method in this interface or its super, java.lang.Object
 855   // JDK8: also look for static methods
 856   methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, false, true));
 857 
 858   if (resolved_method.is_null() && !resolved_klass->is_array_klass()) {
 859     // lookup method in all the super-interfaces
 860     resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
 861   }
 862 
 863   if (resolved_method.is_null()) {
 864     // no method found
 865     ResourceMark rm(THREAD);
 866     stringStream ss;
 867     ss.print("'");
 868     Method::print_external_name(&ss, resolved_klass, link_info.name(), link_info.signature());
 869     ss.print("'");
 870     THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), ss.as_string());
 871   }
 872 
 873   if (link_info.check_access()) {
 874     // JDK8 adds non-public interface methods, and accessability check requirement
 875     Klass* current_klass = link_info.current_klass();
 876 
 877     assert(current_klass != nullptr , "current_klass should not be null");
 878 
 879     // check if method can be accessed by the referring class
 880     check_method_accessability(current_klass,
 881                                resolved_klass,
 882                                resolved_method->method_holder(),
 883                                resolved_method,
 884                                CHECK_NULL);
 885   }
 886   if (link_info.check_loader_constraints()) {
 887     check_method_loader_constraints(link_info, resolved_method, "interface method", CHECK_NULL);
 888   }
 889 
 890   if (code != Bytecodes::_invokestatic && resolved_method->is_static()) {
 891     ResourceMark rm(THREAD);
 892     stringStream ss;
 893     ss.print("Expected instance not static method '");
 894     Method::print_external_name(&ss, resolved_klass,
 895                                 resolved_method->name(), resolved_method->signature());
 896     ss.print("'");
 897     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
 898   }
 899 
 900   if (log_develop_is_enabled(Trace, itables)) {
 901     char buf[200];
 902     jio_snprintf(buf, sizeof(buf), "%s resolved interface method: caller-class:",
 903                  Bytecodes::name(code));
 904     trace_method_resolution(buf, link_info.current_klass(), resolved_klass, resolved_method(), true);
 905   }
 906 
 907   return resolved_method();
 908 }
 909 
 910 //------------------------------------------------------------------------------------------------------------------------
 911 // Field resolution
 912 
 913 void LinkResolver::check_field_accessability(Klass* ref_klass,
 914                                              Klass* resolved_klass,
 915                                              Klass* sel_klass,
 916                                              const fieldDescriptor& fd,
 917                                              TRAPS) {
 918   bool can_access = Reflection::verify_member_access(ref_klass,
 919                                                      resolved_klass,
 920                                                      sel_klass,
 921                                                      fd.access_flags(),
 922                                                      true, false, CHECK);
 923   // Any existing exceptions that may have been thrown, for example LinkageErrors
 924   // from nest-host resolution, have been allowed to propagate.
 925   if (!can_access) {
 926     bool same_module = (sel_klass->module() == ref_klass->module());
 927     ResourceMark rm(THREAD);
 928     stringStream ss;
 929     ss.print("class %s tried to access %s%sfield %s.%s (%s%s%s)",
 930              ref_klass->external_name(),
 931              fd.is_protected() ? "protected " : "",
 932              fd.is_private()   ? "private "   : "",
 933              sel_klass->external_name(),
 934              fd.name()->as_C_string(),
 935              (same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
 936              (same_module) ? "" : "; ",
 937              (same_module) ? "" : sel_klass->class_in_module_of_loader()
 938              );
 939     // For private access see if there was a problem with nest host
 940     // resolution, and if so report that as part of the message.
 941     if (fd.is_private()) {
 942       print_nest_host_error_on(&ss, ref_klass, sel_klass);
 943     }
 944     Exceptions::fthrow(THREAD_AND_LOCATION,
 945                        vmSymbols::java_lang_IllegalAccessError(),
 946                        "%s",
 947                        ss.as_string()
 948                        );
 949     return;
 950   }
 951 }
 952 
 953 void LinkResolver::resolve_field_access(fieldDescriptor& fd, const constantPoolHandle& pool, int index, const methodHandle& method, Bytecodes::Code byte, TRAPS) {
 954   LinkInfo link_info(pool, index, method, byte, CHECK);
 955   resolve_field(fd, link_info, byte, true, CHECK);
 956 }
 957 
 958 void LinkResolver::resolve_field(fieldDescriptor& fd,
 959                                  const LinkInfo& link_info,
 960                                  Bytecodes::Code byte, bool initialize_class,
 961                                  TRAPS) {
 962   assert(byte == Bytecodes::_getstatic || byte == Bytecodes::_putstatic ||
 963          byte == Bytecodes::_getfield  || byte == Bytecodes::_putfield  ||
 964          byte == Bytecodes::_nofast_getfield  || byte == Bytecodes::_nofast_putfield  ||
 965          (byte == Bytecodes::_nop && !link_info.check_access()), "bad field access bytecode");
 966 
 967   bool is_static = (byte == Bytecodes::_getstatic || byte == Bytecodes::_putstatic);
 968   bool is_put    = (byte == Bytecodes::_putfield  || byte == Bytecodes::_putstatic ||
 969                     byte == Bytecodes::_nofast_putfield);
 970   // Check if there's a resolved klass containing the field
 971   Klass* resolved_klass = link_info.resolved_klass();
 972   Symbol* field = link_info.name();
 973   Symbol* sig = link_info.signature();
 974 
 975   // Resolve instance field
 976   Klass* sel_klass = resolved_klass->find_field(field, sig, &fd);
 977   // check if field exists; i.e., if a klass containing the field def has been selected
 978   if (sel_klass == nullptr) {
 979     ResourceMark rm(THREAD);
 980     stringStream ss;
 981     ss.print("Class %s does not have member field '", resolved_klass->external_name());
 982     sig->print_as_field_external_type(&ss);
 983     ss.print(" %s'", field->as_C_string());
 984     THROW_MSG(vmSymbols::java_lang_NoSuchFieldError(), ss.as_string());
 985   }
 986 
 987   // Access checking may be turned off when calling from within the VM.
 988   Klass* current_klass = link_info.current_klass();
 989   if (link_info.check_access()) {
 990 
 991     // check access
 992     check_field_accessability(current_klass, resolved_klass, sel_klass, fd, CHECK);
 993 
 994     // check for errors
 995     if (is_static != fd.is_static()) {
 996       ResourceMark rm(THREAD);
 997       char msg[200];
 998       jio_snprintf(msg, sizeof(msg), "Expected %s field %s.%s", is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string());
 999       THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), msg);
1000     }
1001 
1002     // A final field can be modified only
1003     // (1) by methods declared in the class declaring the field and
1004     // (2) by the <clinit> method (in case of a static field)
1005     //     or by the <init> method (in case of an instance field).
1006     if (is_put && fd.access_flags().is_final()) {
1007 
1008       if (sel_klass != current_klass) {
1009         ResourceMark rm(THREAD);
1010         stringStream ss;
1011         ss.print("Update to %s final field %s.%s attempted from a different class (%s) than the field's declaring class",
1012                   is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
1013                   current_klass->external_name());
1014         THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
1015       }
1016 
1017       if (fd.constants()->pool_holder()->major_version() >= 53) {
1018         Method* m = link_info.current_method();
1019         assert(m != nullptr, "information about the current method must be available for 'put' bytecodes");
1020         bool is_initialized_static_final_update = (byte == Bytecodes::_putstatic &&
1021                                                    fd.is_static() &&
1022                                                    !m->is_class_initializer());
1023         bool is_initialized_instance_final_update = ((byte == Bytecodes::_putfield || byte == Bytecodes::_nofast_putfield) &&
1024                                                      !fd.is_static() &&
1025                                                      !m->is_object_constructor());
1026 
1027         if (is_initialized_static_final_update || is_initialized_instance_final_update) {
1028           ResourceMark rm(THREAD);
1029           stringStream ss;
1030           ss.print("Update to %s final field %s.%s attempted from a different method (%s) than the initializer method %s ",
1031                    is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
1032                    m->name()->as_C_string(),
1033                    is_static ? "<clinit>" : "<init>");
1034           THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
1035         }
1036       }
1037     }
1038 
1039     // initialize resolved_klass if necessary
1040     // note 1: the klass which declared the field must be initialized (i.e, sel_klass)
1041     //         according to the newest JVM spec (5.5, p.170) - was bug (gri 7/28/99)
1042     //
1043     // note 2: we don't want to force initialization if we are just checking
1044     //         if the field access is legal; e.g., during compilation
1045     if (is_static && initialize_class) {
1046       sel_klass->initialize(CHECK);
1047     }
1048   }
1049 
1050   if (link_info.check_loader_constraints() && (sel_klass != current_klass) && (current_klass != nullptr)) {
1051     check_field_loader_constraints(field, sig, current_klass, sel_klass, CHECK);
1052   }
1053 
1054   // return information. note that the klass is set to the actual klass containing the
1055   // field, otherwise access of static fields in superclasses will not work.
1056 }
1057 
1058 
1059 //------------------------------------------------------------------------------------------------------------------------
1060 // Invoke resolution
1061 //
1062 // Naming conventions:
1063 //
1064 // resolved_method    the specified method (i.e., static receiver specified via constant pool index)
1065 // sel_method         the selected method  (selected via run-time lookup; e.g., based on dynamic receiver class)
1066 // resolved_klass     the specified klass  (i.e., specified via constant pool index)
1067 // recv_klass         the receiver klass
1068 
1069 
1070 void LinkResolver::resolve_static_call(CallInfo& result,
1071                                        const LinkInfo& link_info,
1072                                        bool initialize_class, TRAPS) {
1073   Method* resolved_method = linktime_resolve_static_method(link_info, CHECK);
1074 
1075   // The resolved class can change as a result of this resolution.
1076   Klass* resolved_klass = resolved_method->method_holder();
1077 
1078   // Initialize klass (this should only happen if everything is ok)
1079   if (initialize_class && resolved_klass->should_be_initialized()) {
1080     resolved_klass->initialize(CHECK);
1081     // Use updated LinkInfo to reresolve with resolved method holder
1082     LinkInfo new_info(resolved_klass, link_info.name(), link_info.signature(),
1083                       link_info.current_klass(),
1084                       link_info.check_access() ? LinkInfo::AccessCheck::required : LinkInfo::AccessCheck::skip,
1085                       link_info.check_loader_constraints() ? LinkInfo::LoaderConstraintCheck::required : LinkInfo::LoaderConstraintCheck::skip);
1086     resolved_method = linktime_resolve_static_method(new_info, CHECK);
1087   }
1088 
1089   if (resolved_method->is_continuation_native_intrinsic()
1090       && resolved_method->from_interpreted_entry() == nullptr) { // does a load_acquire
1091     methodHandle mh(THREAD, resolved_method);
1092     // Generate a compiled form of the enterSpecial intrinsic.
1093     AdapterHandlerLibrary::create_native_wrapper(mh);
1094   }
1095 
1096   // setup result
1097   result.set_static(resolved_klass, methodHandle(THREAD, resolved_method), CHECK);
1098   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1099 }
1100 
1101 // throws linktime exceptions
1102 Method* LinkResolver::linktime_resolve_static_method(const LinkInfo& link_info, TRAPS) {
1103 
1104   Klass* resolved_klass = link_info.resolved_klass();
1105   Method* resolved_method;
1106   if (!resolved_klass->is_interface()) {
1107     resolved_method = resolve_method(link_info, Bytecodes::_invokestatic, CHECK_NULL);
1108   } else {
1109     resolved_method = resolve_interface_method(link_info, Bytecodes::_invokestatic, CHECK_NULL);
1110   }
1111   assert(resolved_method->name() != vmSymbols::class_initializer_name(), "should have been checked in verifier");
1112 
1113   // check if static
1114   if (!resolved_method->is_static()) {
1115     ResourceMark rm(THREAD);
1116     stringStream ss;
1117     ss.print("Expected static method '");
1118     resolved_method->print_external_name(&ss);
1119     ss.print("'");
1120     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1121   }
1122   return resolved_method;
1123 }
1124 
1125 
1126 void LinkResolver::resolve_special_call(CallInfo& result,
1127                                         Handle recv,
1128                                         const LinkInfo& link_info,
1129                                         TRAPS) {
1130   Method* resolved_method = linktime_resolve_special_method(link_info, CHECK);
1131   runtime_resolve_special_method(result, link_info, methodHandle(THREAD, resolved_method), recv, CHECK);
1132 }
1133 
1134 // throws linktime exceptions
1135 Method* LinkResolver::linktime_resolve_special_method(const LinkInfo& link_info, TRAPS) {
1136 
1137   // Invokespecial is called for multiple special reasons:
1138   // <init>
1139   // local private method invocation, for classes and interfaces
1140   // superclass.method, which can also resolve to a default method
1141   // and the selected method is recalculated relative to the direct superclass
1142   // superinterface.method, which explicitly does not check shadowing
1143   Klass* resolved_klass = link_info.resolved_klass();
1144   Method* resolved_method = nullptr;
1145 
1146   if (!resolved_klass->is_interface()) {
1147     resolved_method = resolve_method(link_info, Bytecodes::_invokespecial, CHECK_NULL);
1148   } else {
1149     resolved_method = resolve_interface_method(link_info, Bytecodes::_invokespecial, CHECK_NULL);
1150   }
1151 
1152   // check if method name is <init>, that it is found in same klass as static type
1153   // Since this method is never inherited from a super, any appearance here under
1154   // the wrong class would be an error.
1155   if (resolved_method->name() == vmSymbols::object_initializer_name() &&
1156       resolved_method->method_holder() != resolved_klass) {
1157     ResourceMark rm(THREAD);
1158     stringStream ss;
1159     ss.print("%s: method '", resolved_klass->external_name());
1160     resolved_method->signature()->print_as_signature_external_return_type(&ss);
1161     ss.print(" %s(", resolved_method->name()->as_C_string());
1162     resolved_method->signature()->print_as_signature_external_parameters(&ss);
1163     ss.print(")' not found");
1164     Exceptions::fthrow(
1165       THREAD_AND_LOCATION,
1166       vmSymbols::java_lang_NoSuchMethodError(),
1167       "%s", ss.as_string());
1168     return nullptr;
1169   }
1170 
1171   // ensure that invokespecial's interface method reference is in
1172   // a direct superinterface, not an indirect superinterface
1173   Klass* current_klass = link_info.current_klass();
1174   if (current_klass != nullptr && resolved_klass->is_interface()) {
1175     InstanceKlass* klass_to_check = InstanceKlass::cast(current_klass);
1176     // Disable verification for the dynamically-generated reflection bytecodes
1177     // for serialization constructor accessor.
1178     bool is_reflect = klass_to_check->is_subclass_of(
1179                         vmClasses::reflect_SerializationConstructorAccessorImpl_klass());
1180 
1181     if (!is_reflect &&
1182         !klass_to_check->is_same_or_direct_interface(resolved_klass)) {
1183       ResourceMark rm(THREAD);
1184       stringStream ss;
1185       ss.print("Interface method reference: '");
1186       resolved_method->print_external_name(&ss);
1187       ss.print("', is in an indirect superinterface of %s",
1188                current_klass->external_name());
1189       THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1190     }
1191   }
1192 
1193   // check if not static
1194   if (resolved_method->is_static()) {
1195     ResourceMark rm(THREAD);
1196     stringStream ss;
1197     ss.print("Expecting non-static method '");
1198     resolved_method->print_external_name(&ss);
1199     ss.print("'");
1200     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1201   }
1202 
1203   if (log_develop_is_enabled(Trace, itables)) {
1204     trace_method_resolution("invokespecial resolved method: caller-class:",
1205                             current_klass, resolved_klass, resolved_method, true);
1206   }
1207 
1208   return resolved_method;
1209 }
1210 
1211 // throws runtime exceptions
1212 void LinkResolver::runtime_resolve_special_method(CallInfo& result,
1213                                                   const LinkInfo& link_info,
1214                                                   const methodHandle& resolved_method,
1215                                                   Handle recv, TRAPS) {
1216 
1217   Klass* resolved_klass = link_info.resolved_klass();
1218 
1219   // resolved method is selected method unless we have an old-style lookup
1220   // for a superclass method
1221   // Invokespecial for a superinterface, resolved method is selected method,
1222   // no checks for shadowing
1223   methodHandle sel_method(THREAD, resolved_method());
1224 
1225   if (link_info.check_access() &&
1226       // check if the method is not <init>, which is never inherited
1227       resolved_method->name() != vmSymbols::object_initializer_name()) {
1228 
1229     Klass* current_klass = link_info.current_klass();
1230 
1231     // Check if the class of the resolved_klass is a superclass
1232     // (not supertype in order to exclude interface classes) of the current class.
1233     // This check is not performed for super.invoke for interface methods
1234     // in super interfaces.
1235     if (current_klass->is_subclass_of(resolved_klass) &&
1236         current_klass != resolved_klass) {
1237       // Lookup super method
1238       Klass* super_klass = current_klass->super();
1239       Method* instance_method = lookup_instance_method_in_klasses(super_klass,
1240                                                      resolved_method->name(),
1241                                                      resolved_method->signature(),
1242                                                      Klass::PrivateLookupMode::find);
1243       sel_method = methodHandle(THREAD, instance_method);
1244 
1245       // check if found
1246       if (sel_method.is_null()) {
1247         ResourceMark rm(THREAD);
1248         stringStream ss;
1249         ss.print("'");
1250         resolved_method->print_external_name(&ss);
1251         ss.print("'");
1252         THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
1253       // check loader constraints if found a different method
1254       } else if (link_info.check_loader_constraints() && sel_method() != resolved_method()) {
1255         check_method_loader_constraints(link_info, sel_method, "method", CHECK);
1256       }
1257     }
1258 
1259     // Check that the class of objectref (the receiver) is the current class or interface,
1260     // or a subtype of the current class or interface (the sender), otherwise invokespecial
1261     // throws IllegalAccessError.
1262     // The verifier checks that the sender is a subtype of the class in the I/MR operand.
1263     // The verifier also checks that the receiver is a subtype of the sender, if the sender is
1264     // a class.  If the sender is an interface, the check has to be performed at runtime.
1265     InstanceKlass* sender = InstanceKlass::cast(current_klass);
1266     if (sender->is_interface() && recv.not_null()) {
1267       Klass* receiver_klass = recv->klass();
1268       if (!receiver_klass->is_subtype_of(sender)) {
1269         ResourceMark rm(THREAD);
1270         char buf[500];
1271         jio_snprintf(buf, sizeof(buf),
1272                      "Receiver class %s must be the current class or a subtype of interface %s",
1273                      receiver_klass->external_name(),
1274                      sender->external_name());
1275         THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), buf);
1276       }
1277     }
1278   }
1279 
1280   // check if not static
1281   if (sel_method->is_static()) {
1282     ResourceMark rm(THREAD);
1283     stringStream ss;
1284     ss.print("Expecting non-static method '");
1285     resolved_method->print_external_name(&ss);
1286     ss.print("'");
1287     THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1288   }
1289 
1290   // check if abstract
1291   if (sel_method->is_abstract()) {
1292     ResourceMark rm(THREAD);
1293     stringStream ss;
1294     ss.print("'");
1295     Method::print_external_name(&ss, resolved_klass, sel_method->name(), sel_method->signature());
1296     ss.print("'");
1297     THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
1298   }
1299 
1300   if (log_develop_is_enabled(Trace, itables)) {
1301     trace_method_resolution("invokespecial selected method: resolved-class:",
1302                             resolved_klass, resolved_klass, sel_method(), true);
1303   }
1304 
1305   // setup result
1306   result.set_static(resolved_klass, sel_method, CHECK);
1307   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1308 }
1309 
1310 void LinkResolver::resolve_virtual_call(CallInfo& result, Handle recv, Klass* receiver_klass,
1311                                         const LinkInfo& link_info,
1312                                         bool check_null_and_abstract, TRAPS) {
1313   Method* resolved_method = linktime_resolve_virtual_method(link_info, CHECK);
1314   runtime_resolve_virtual_method(result, methodHandle(THREAD, resolved_method),
1315                                  link_info.resolved_klass(),
1316                                  recv, receiver_klass,
1317                                  check_null_and_abstract, CHECK);
1318 }
1319 
1320 // throws linktime exceptions
1321 Method* LinkResolver::linktime_resolve_virtual_method(const LinkInfo& link_info,
1322                                                            TRAPS) {
1323   // normal method resolution
1324   Method* resolved_method = resolve_method(link_info, Bytecodes::_invokevirtual, CHECK_NULL);
1325 
1326   assert(resolved_method->name() != vmSymbols::object_initializer_name(), "should have been checked in verifier");
1327   assert(resolved_method->name() != vmSymbols::class_initializer_name (), "should have been checked in verifier");
1328 
1329   // check if private interface method
1330   Klass* resolved_klass = link_info.resolved_klass();
1331   Klass* current_klass = link_info.current_klass();
1332 
1333   // This is impossible, if resolve_klass is an interface, we've thrown icce in resolve_method
1334   if (resolved_klass->is_interface() && resolved_method->is_private()) {
1335     ResourceMark rm(THREAD);
1336     stringStream ss;
1337     ss.print("private interface method requires invokespecial, not invokevirtual: method '");
1338     resolved_method->print_external_name(&ss);
1339     ss.print("', caller-class: %s",
1340              (current_klass == nullptr ? "<null>" : current_klass->internal_name()));
1341     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1342   }
1343 
1344   // check if not static
1345   if (resolved_method->is_static()) {
1346     ResourceMark rm(THREAD);
1347     stringStream ss;
1348     ss.print("Expecting non-static method '");
1349     resolved_method->print_external_name(&ss);
1350     ss.print("'");
1351     THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
1352   }
1353 
1354   if (log_develop_is_enabled(Trace, vtables)) {
1355     trace_method_resolution("invokevirtual resolved method: caller-class:",
1356                             current_klass, resolved_klass, resolved_method, false);
1357   }
1358 
1359   return resolved_method;
1360 }
1361 
1362 // throws runtime exceptions
1363 void LinkResolver::runtime_resolve_virtual_method(CallInfo& result,
1364                                                   const methodHandle& resolved_method,
1365                                                   Klass* resolved_klass,
1366                                                   Handle recv,
1367                                                   Klass* recv_klass,
1368                                                   bool check_null_and_abstract,
1369                                                   TRAPS) {
1370 
1371   // setup default return values
1372   int vtable_index = Method::invalid_vtable_index;
1373   methodHandle selected_method;
1374 
1375   // runtime method resolution
1376   if (check_null_and_abstract && recv.is_null()) { // check if receiver exists
1377     THROW(vmSymbols::java_lang_NullPointerException());
1378   }
1379 
1380   // Virtual methods cannot be resolved before its klass has been linked, for otherwise the Method*'s
1381   // has not been rewritten, and the vtable initialized. Make sure to do this after the nullcheck, since
1382   // a missing receiver might result in a bogus lookup.
1383   assert(resolved_method->method_holder()->is_linked(), "must be linked");
1384 
1385   // do lookup based on receiver klass using the vtable index
1386   if (resolved_method->method_holder()->is_interface()) { // default or miranda method
1387     vtable_index = vtable_index_of_interface_method(resolved_klass, resolved_method);
1388     assert(vtable_index >= 0 , "we should have valid vtable index at this point");
1389 
1390     selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
1391   } else {
1392     // at this point we are sure that resolved_method is virtual and not
1393     // a default or miranda method; therefore, it must have a valid vtable index.
1394     assert(!resolved_method->has_itable_index(), "");
1395     vtable_index = resolved_method->vtable_index();
1396     // We could get a negative vtable_index of nonvirtual_vtable_index for private
1397     // methods, or for final methods. Private methods never appear in the vtable
1398     // and never override other methods. As an optimization, final methods are
1399     // never put in the vtable, unless they override an existing method.
1400     // So if we do get nonvirtual_vtable_index, it means the selected method is the
1401     // resolved method, and it can never be changed by an override.
1402     if (vtable_index == Method::nonvirtual_vtable_index) {
1403       assert(resolved_method->can_be_statically_bound(), "cannot override this method");
1404       selected_method = resolved_method;
1405     } else {
1406       selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
1407     }
1408   }
1409 
1410   // check if method exists
1411   if (selected_method.is_null()) {
1412     throw_abstract_method_error(resolved_method, recv_klass, CHECK);
1413   }
1414 
1415   // check if abstract
1416   if (check_null_and_abstract && selected_method->is_abstract()) {
1417     // Pass arguments for generating a verbose error message.
1418     throw_abstract_method_error(resolved_method, selected_method, recv_klass, CHECK);
1419   }
1420 
1421   if (log_develop_is_enabled(Trace, vtables)) {
1422     trace_method_resolution("invokevirtual selected method: receiver-class:",
1423                             recv_klass, resolved_klass, selected_method(),
1424                             false, vtable_index);
1425   }
1426   // setup result
1427   result.set_virtual(resolved_klass, resolved_method, selected_method, vtable_index, CHECK);
1428   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1429 }
1430 
1431 void LinkResolver::resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass,
1432                                           const LinkInfo& link_info,
1433                                           bool check_null_and_abstract, TRAPS) {
1434   // throws linktime exceptions
1435   Method* resolved_method = linktime_resolve_interface_method(link_info, CHECK);
1436   methodHandle mh(THREAD, resolved_method);
1437   runtime_resolve_interface_method(result, mh, link_info.resolved_klass(),
1438                                    recv, recv_klass, check_null_and_abstract, CHECK);
1439 }
1440 
1441 Method* LinkResolver::linktime_resolve_interface_method(const LinkInfo& link_info,
1442                                                              TRAPS) {
1443   // normal interface method resolution
1444   Method* resolved_method = resolve_interface_method(link_info, Bytecodes::_invokeinterface, CHECK_NULL);
1445   assert(resolved_method->name() != vmSymbols::object_initializer_name(), "should have been checked in verifier");
1446   assert(resolved_method->name() != vmSymbols::class_initializer_name (), "should have been checked in verifier");
1447 
1448   return resolved_method;
1449 }
1450 
1451 // throws runtime exceptions
1452 void LinkResolver::runtime_resolve_interface_method(CallInfo& result,
1453                                                     const methodHandle& resolved_method,
1454                                                     Klass* resolved_klass,
1455                                                     Handle recv,
1456                                                     Klass* recv_klass,
1457                                                     bool check_null_and_abstract, TRAPS) {
1458 
1459   // check if receiver exists
1460   if (check_null_and_abstract && recv.is_null()) {
1461     THROW(vmSymbols::java_lang_NullPointerException());
1462   }
1463 
1464   // check if receiver klass implements the resolved interface
1465   if (!recv_klass->is_subtype_of(resolved_klass)) {
1466     ResourceMark rm(THREAD);
1467     char buf[200];
1468     jio_snprintf(buf, sizeof(buf), "Class %s does not implement the requested interface %s",
1469                  recv_klass->external_name(),
1470                  resolved_klass->external_name());
1471     THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
1472   }
1473 
1474   methodHandle selected_method = resolved_method;
1475 
1476   // resolve the method in the receiver class, unless it is private
1477   if (!resolved_method()->is_private()) {
1478     // do lookup based on receiver klass
1479     // This search must match the linktime preparation search for itable initialization
1480     // to correctly enforce loader constraints for interface method inheritance.
1481     // Private methods are skipped as the resolved method was not private.
1482     Method* method = lookup_instance_method_in_klasses(recv_klass,
1483                                                        resolved_method->name(),
1484                                                        resolved_method->signature(),
1485                                                        Klass::PrivateLookupMode::skip);
1486     selected_method = methodHandle(THREAD, method);
1487 
1488     if (selected_method.is_null() && !check_null_and_abstract) {
1489       // In theory this is a harmless placeholder value, but
1490       // in practice leaving in null affects the nsk default method tests.
1491       // This needs further study.
1492       selected_method = resolved_method;
1493     }
1494     // check if method exists
1495     if (selected_method.is_null()) {
1496       // Pass arguments for generating a verbose error message.
1497       throw_abstract_method_error(resolved_method, recv_klass, CHECK);
1498     }
1499     // check access
1500     // Throw Illegal Access Error if selected_method is not public.
1501     if (!selected_method->is_public()) {
1502       ResourceMark rm(THREAD);
1503       stringStream ss;
1504       ss.print("'");
1505       Method::print_external_name(&ss, recv_klass, selected_method->name(), selected_method->signature());
1506       ss.print("'");
1507       THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
1508     }
1509     // check if abstract
1510     if (check_null_and_abstract && selected_method->is_abstract()) {
1511       throw_abstract_method_error(resolved_method, selected_method, recv_klass, CHECK);
1512     }
1513   }
1514 
1515   if (log_develop_is_enabled(Trace, itables)) {
1516     trace_method_resolution("invokeinterface selected method: receiver-class:",
1517                             recv_klass, resolved_klass, selected_method(), true);
1518   }
1519   // setup result
1520   if (resolved_method->has_vtable_index()) {
1521     int vtable_index = resolved_method->vtable_index();
1522     log_develop_trace(itables)("  -- vtable index: %d", vtable_index);
1523     assert(vtable_index == selected_method->vtable_index(), "sanity check");
1524     result.set_virtual(resolved_klass, resolved_method, selected_method, vtable_index, CHECK);
1525   } else if (resolved_method->has_itable_index()) {
1526     int itable_index = resolved_method()->itable_index();
1527     log_develop_trace(itables)("  -- itable index: %d", itable_index);
1528     result.set_interface(resolved_klass, resolved_method, selected_method, itable_index, CHECK);
1529   } else {
1530     int index = resolved_method->vtable_index();
1531     log_develop_trace(itables)("  -- non itable/vtable index: %d", index);
1532     assert(index == Method::nonvirtual_vtable_index, "Oops hit another case!");
1533     assert(resolved_method()->is_private() ||
1534            (resolved_method()->is_final() && resolved_method->method_holder() == vmClasses::Object_klass()),
1535            "Should only have non-virtual invokeinterface for private or final-Object methods!");
1536     assert(resolved_method()->can_be_statically_bound(), "Should only have non-virtual invokeinterface for statically bound methods!");
1537     // This sets up the nonvirtual form of "virtual" call (as needed for final and private methods)
1538     result.set_virtual(resolved_klass, resolved_method, resolved_method, index, CHECK);
1539   }
1540   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1541 }
1542 
1543 
1544 Method* LinkResolver::linktime_resolve_interface_method_or_null(
1545                                                  const LinkInfo& link_info) {
1546   EXCEPTION_MARK;
1547   Method* method_result = linktime_resolve_interface_method(link_info, THREAD);
1548   if (HAS_PENDING_EXCEPTION) {
1549     CLEAR_PENDING_EXCEPTION;
1550     return nullptr;
1551   } else {
1552     return method_result;
1553   }
1554 }
1555 
1556 Method* LinkResolver::linktime_resolve_virtual_method_or_null(
1557                                                  const LinkInfo& link_info) {
1558   EXCEPTION_MARK;
1559   Method* method_result = linktime_resolve_virtual_method(link_info, THREAD);
1560   if (HAS_PENDING_EXCEPTION) {
1561     CLEAR_PENDING_EXCEPTION;
1562     return nullptr;
1563   } else {
1564     return method_result;
1565   }
1566 }
1567 
1568 Method* LinkResolver::resolve_virtual_call_or_null(
1569                                                  Klass* receiver_klass,
1570                                                  const LinkInfo& link_info) {
1571   EXCEPTION_MARK;
1572   CallInfo info;
1573   resolve_virtual_call(info, Handle(), receiver_klass, link_info, false, THREAD);
1574   if (HAS_PENDING_EXCEPTION) {
1575     CLEAR_PENDING_EXCEPTION;
1576     return nullptr;
1577   }
1578   return info.selected_method();
1579 }
1580 
1581 Method* LinkResolver::resolve_interface_call_or_null(
1582                                                  Klass* receiver_klass,
1583                                                  const LinkInfo& link_info) {
1584   EXCEPTION_MARK;
1585   CallInfo info;
1586   resolve_interface_call(info, Handle(), receiver_klass, link_info, false, THREAD);
1587   if (HAS_PENDING_EXCEPTION) {
1588     CLEAR_PENDING_EXCEPTION;
1589     return nullptr;
1590   }
1591   return info.selected_method();
1592 }
1593 
1594 int LinkResolver::resolve_virtual_vtable_index(Klass* receiver_klass,
1595                                                const LinkInfo& link_info) {
1596   EXCEPTION_MARK;
1597   CallInfo info;
1598   resolve_virtual_call(info, Handle(), receiver_klass, link_info,
1599                        /*check_null_or_abstract*/false, THREAD);
1600   if (HAS_PENDING_EXCEPTION) {
1601     CLEAR_PENDING_EXCEPTION;
1602     return Method::invalid_vtable_index;
1603   }
1604   return info.vtable_index();
1605 }
1606 
1607 Method* LinkResolver::resolve_static_call_or_null(const LinkInfo& link_info) {
1608   EXCEPTION_MARK;
1609   CallInfo info;
1610   resolve_static_call(info, link_info, /*initialize_class*/false, THREAD);
1611   if (HAS_PENDING_EXCEPTION) {
1612     CLEAR_PENDING_EXCEPTION;
1613     return nullptr;
1614   }
1615   return info.selected_method();
1616 }
1617 
1618 Method* LinkResolver::resolve_special_call_or_null(const LinkInfo& link_info) {
1619   EXCEPTION_MARK;
1620   CallInfo info;
1621   resolve_special_call(info, Handle(), link_info, THREAD);
1622   if (HAS_PENDING_EXCEPTION) {
1623     CLEAR_PENDING_EXCEPTION;
1624     return nullptr;
1625   }
1626   return info.selected_method();
1627 }
1628 
1629 
1630 
1631 //------------------------------------------------------------------------------------------------------------------------
1632 // ConstantPool entries
1633 
1634 void LinkResolver::resolve_invoke(CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, Bytecodes::Code byte, TRAPS) {
1635   switch (byte) {
1636     case Bytecodes::_invokestatic   : resolve_invokestatic   (result,       pool, index, CHECK); break;
1637     case Bytecodes::_invokespecial  : resolve_invokespecial  (result, recv, pool, index, CHECK); break;
1638     case Bytecodes::_invokevirtual  : resolve_invokevirtual  (result, recv, pool, index, CHECK); break;
1639     case Bytecodes::_invokehandle   : resolve_invokehandle   (result,       pool, index, CHECK); break;
1640     case Bytecodes::_invokedynamic  : resolve_invokedynamic  (result,       pool, index, CHECK); break;
1641     case Bytecodes::_invokeinterface: resolve_invokeinterface(result, recv, pool, index, CHECK); break;
1642     default                         :                                                            break;
1643   }
1644   return;
1645 }
1646 
1647 void LinkResolver::resolve_invoke(CallInfo& result, Handle& recv,
1648                                   const methodHandle& attached_method,
1649                                   Bytecodes::Code byte, bool check_null_and_abstract, TRAPS) {
1650   Klass* defc = attached_method->method_holder();
1651   Symbol* name = attached_method->name();
1652   Symbol* type = attached_method->signature();
1653   LinkInfo link_info(defc, name, type);
1654   Klass* recv_klass = recv.is_null() ? defc : recv->klass();
1655   switch(byte) {
1656     case Bytecodes::_invokevirtual:
1657       resolve_virtual_call(result, recv, recv_klass, link_info,
1658                            check_null_and_abstract, CHECK);
1659       break;
1660     case Bytecodes::_invokeinterface:
1661       resolve_interface_call(result, recv, recv_klass, link_info,
1662                              check_null_and_abstract, CHECK);
1663       break;
1664     case Bytecodes::_invokestatic:
1665       resolve_static_call(result, link_info, /*initialize_class=*/false, CHECK);
1666       break;
1667     case Bytecodes::_invokespecial:
1668       resolve_special_call(result, recv, link_info, CHECK);
1669       break;
1670     default:
1671       fatal("bad call: %s", Bytecodes::name(byte));
1672       break;
1673   }
1674 }
1675 
1676 void LinkResolver::resolve_invokestatic(CallInfo& result, const constantPoolHandle& pool, int index, TRAPS) {
1677   LinkInfo link_info(pool, index, Bytecodes::_invokestatic, CHECK);
1678   resolve_static_call(result, link_info, /*initialize_class*/true, CHECK);
1679 }
1680 
1681 
1682 void LinkResolver::resolve_invokespecial(CallInfo& result, Handle recv,
1683                                          const constantPoolHandle& pool, int index, TRAPS) {
1684   LinkInfo link_info(pool, index, Bytecodes::_invokespecial, CHECK);
1685   resolve_special_call(result, recv, link_info, CHECK);
1686 }
1687 
1688 
1689 void LinkResolver::resolve_invokevirtual(CallInfo& result, Handle recv,
1690                                           const constantPoolHandle& pool, int index,
1691                                           TRAPS) {
1692 
1693   LinkInfo link_info(pool, index, Bytecodes::_invokevirtual, CHECK);
1694   Klass* recvrKlass = recv.is_null() ? (Klass*)nullptr : recv->klass();
1695   resolve_virtual_call(result, recv, recvrKlass, link_info, /*check_null_or_abstract*/true, CHECK);
1696 }
1697 
1698 
1699 void LinkResolver::resolve_invokeinterface(CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, TRAPS) {
1700   LinkInfo link_info(pool, index, Bytecodes::_invokeinterface, CHECK);
1701   Klass* recvrKlass = recv.is_null() ? (Klass*)nullptr : recv->klass();
1702   resolve_interface_call(result, recv, recvrKlass, link_info, true, CHECK);
1703 }
1704 
1705 bool LinkResolver::resolve_previously_linked_invokehandle(CallInfo& result, const LinkInfo& link_info, const constantPoolHandle& pool, int index, TRAPS) {
1706   ResolvedMethodEntry* method_entry = pool->cache()->resolved_method_entry_at(index);
1707   if (method_entry->method() != nullptr) {
1708     Klass* resolved_klass = link_info.resolved_klass();
1709     methodHandle method(THREAD, method_entry->method());
1710     Handle     appendix(THREAD, pool->cache()->appendix_if_resolved(method_entry));
1711     result.set_handle(resolved_klass, method, appendix, CHECK_false);
1712     JFR_ONLY(Jfr::on_resolution(result, CHECK_false);)
1713     return true;
1714   } else {
1715     return false;
1716   }
1717 }
1718 
1719 void LinkResolver::resolve_invokehandle(CallInfo& result, const constantPoolHandle& pool, int index, TRAPS) {
1720   LinkInfo link_info(pool, index, Bytecodes::_invokehandle, CHECK);
1721   if (log_is_enabled(Info, methodhandles)) {
1722     ResourceMark rm(THREAD);
1723     log_info(methodhandles)("resolve_invokehandle %s %s", link_info.name()->as_C_string(),
1724                             link_info.signature()->as_C_string());
1725   }
1726   { // Check if the call site has been bound already, and short circuit:
1727     bool is_done = resolve_previously_linked_invokehandle(result, link_info, pool, index, CHECK);
1728     if (is_done) return;
1729   }
1730   resolve_handle_call(result, link_info, CHECK);
1731 }
1732 
1733 void LinkResolver::resolve_handle_call(CallInfo& result,
1734                                        const LinkInfo& link_info,
1735                                        TRAPS) {
1736   // JSR 292:  this must be an implicitly generated method MethodHandle.invokeExact(*...) or similar
1737   Klass* resolved_klass = link_info.resolved_klass();
1738   assert(resolved_klass == vmClasses::MethodHandle_klass() ||
1739          resolved_klass == vmClasses::VarHandle_klass(), "");
1740   assert(MethodHandles::is_signature_polymorphic_name(link_info.name()), "");
1741   Handle resolved_appendix;
1742   Method* m = lookup_polymorphic_method(link_info, &resolved_appendix, CHECK);
1743   methodHandle resolved_method(THREAD, m);
1744 
1745   if (link_info.check_access()) {
1746     Symbol* name = link_info.name();
1747     vmIntrinsics::ID iid = MethodHandles::signature_polymorphic_name_id(name);
1748     if (MethodHandles::is_signature_polymorphic_intrinsic(iid)) {
1749       // Check if method can be accessed by the referring class.
1750       // MH.linkTo* invocations are not rewritten to invokehandle.
1751       assert(iid == vmIntrinsicID::_invokeBasic, "%s", vmIntrinsics::name_at(iid));
1752 
1753       Klass* current_klass = link_info.current_klass();
1754       assert(current_klass != nullptr , "current_klass should not be null");
1755       check_method_accessability(current_klass,
1756                                  resolved_klass,
1757                                  resolved_method->method_holder(),
1758                                  resolved_method,
1759                                  CHECK);
1760     } else {
1761       // Java code is free to arbitrarily link signature-polymorphic invokers.
1762       assert(iid == vmIntrinsics::_invokeGeneric, "not an invoker: %s", vmIntrinsics::name_at(iid));
1763       assert(MethodHandles::is_signature_polymorphic_public_name(resolved_klass, name), "not public");
1764     }
1765   }
1766   result.set_handle(resolved_klass, resolved_method, resolved_appendix, CHECK);
1767   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1768 }
1769 
1770 void LinkResolver::resolve_invokedynamic(CallInfo& result, const constantPoolHandle& pool, int indy_index, TRAPS) {
1771   int index = pool->decode_invokedynamic_index(indy_index);
1772   int pool_index = pool->resolved_indy_entry_at(index)->constant_pool_index();
1773 
1774   // Resolve the bootstrap specifier (BSM + optional arguments).
1775   BootstrapInfo bootstrap_specifier(pool, pool_index, index);
1776 
1777   // Check if CallSite has been bound already or failed already, and short circuit:
1778   {
1779     bool is_done = bootstrap_specifier.resolve_previously_linked_invokedynamic(result, CHECK);
1780     if (is_done) return;
1781   }
1782 
1783   // The initial step in Call Site Specifier Resolution is to resolve the symbolic
1784   // reference to a method handle which will be the bootstrap method for a dynamic
1785   // call site.  If resolution for the java.lang.invoke.MethodHandle for the bootstrap
1786   // method fails, then a MethodHandleInError is stored at the corresponding bootstrap
1787   // method's CP index for the CONSTANT_MethodHandle_info.
1788   // Any subsequent invokedynamic instruction which shares
1789   // this bootstrap method will encounter the resolution of MethodHandleInError.
1790 
1791   resolve_dynamic_call(result, bootstrap_specifier, CHECK);
1792 
1793   LogTarget(Debug, methodhandles, indy) lt_indy;
1794   if (lt_indy.is_enabled()) {
1795     LogStream ls(lt_indy);
1796     bootstrap_specifier.print_msg_on(&ls, "resolve_invokedynamic");
1797   }
1798 
1799   // The returned linkage result is provisional up to the moment
1800   // the interpreter or runtime performs a serialized check of
1801   // the relevant ResolvedIndyEntry::method field.  This is done by the caller
1802   // of this method, via CPC::set_dynamic_call, which uses
1803   // a lock to do the final serialization of updates
1804   // to ResolvedIndyEntry state, including method.
1805 
1806   // Log dynamic info to CDS classlist.
1807   ArchiveUtils::log_to_classlist(&bootstrap_specifier, CHECK);
1808 }
1809 
1810 void LinkResolver::resolve_dynamic_call(CallInfo& result,
1811                                         BootstrapInfo& bootstrap_specifier,
1812                                         TRAPS) {
1813   // JSR 292:  this must resolve to an implicitly generated method
1814   // such as MH.linkToCallSite(*...) or some other call-site shape.
1815   // The appendix argument is likely to be a freshly-created CallSite.
1816   // It may also be a MethodHandle from an unwrapped ConstantCallSite,
1817   // or any other reference.  The resolved_method as well as the appendix
1818   // are both recorded together via CallInfo::set_handle.
1819   SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1820   Exceptions::wrap_dynamic_exception(/* is_indy */ true, THREAD);
1821 
1822   if (HAS_PENDING_EXCEPTION) {
1823     if (!PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1824       // Let any random low-level IE or SOE or OOME just bleed through.
1825       // Basically we pretend that the bootstrap method was never called,
1826       // if it fails this way:  We neither record a successful linkage,
1827       // nor do we memorize a LE for posterity.
1828       return;
1829     }
1830     // JVMS 5.4.3 says: If an attempt by the Java Virtual Machine to resolve
1831     // a symbolic reference fails because an error is thrown that is an
1832     // instance of LinkageError (or a subclass), then subsequent attempts to
1833     // resolve the reference always fail with the same error that was thrown
1834     // as a result of the initial resolution attempt.
1835     bool recorded_res_status = bootstrap_specifier.save_and_throw_indy_exc(CHECK);
1836     if (!recorded_res_status) {
1837       // Another thread got here just before we did.  So, either use the method
1838       // that it resolved or throw the LinkageError exception that it threw.
1839       bool is_done = bootstrap_specifier.resolve_previously_linked_invokedynamic(result, CHECK);
1840       if (is_done) return;
1841     }
1842     assert(bootstrap_specifier.pool()->resolved_indy_entry_at(bootstrap_specifier.indy_index())->resolution_failed(),
1843           "Resolution should have failed");
1844   }
1845 
1846   bootstrap_specifier.resolve_newly_linked_invokedynamic(result, CHECK);
1847   // Exceptions::wrap_dynamic_exception not used because
1848   // set_handle doesn't throw linkage errors
1849   JFR_ONLY(Jfr::on_resolution(result, CHECK);)
1850 }
1851 
1852 // Selected method is abstract.
1853 void LinkResolver::throw_abstract_method_error(const methodHandle& resolved_method,
1854                                                const methodHandle& selected_method,
1855                                                Klass *recv_klass, TRAPS) {
1856   Klass *resolved_klass = resolved_method->method_holder();
1857   ResourceMark rm(THREAD);
1858   stringStream ss;
1859 
1860   if (recv_klass != nullptr) {
1861     ss.print("Receiver class %s does not define or inherit an "
1862              "implementation of the",
1863              recv_klass->external_name());
1864   } else {
1865     ss.print("Missing implementation of");
1866   }
1867 
1868   assert(resolved_method.not_null(), "Sanity");
1869   ss.print(" resolved method '%s%s",
1870            resolved_method->is_abstract() ? "abstract " : "",
1871            resolved_method->is_private()  ? "private "  : "");
1872   resolved_method->signature()->print_as_signature_external_return_type(&ss);
1873   ss.print(" %s(", resolved_method->name()->as_C_string());
1874   resolved_method->signature()->print_as_signature_external_parameters(&ss);
1875   ss.print(")' of %s %s.",
1876            resolved_klass->external_kind(),
1877            resolved_klass->external_name());
1878 
1879   if (selected_method.not_null() && !(resolved_method == selected_method)) {
1880     ss.print(" Selected method is '%s%s",
1881              selected_method->is_abstract() ? "abstract " : "",
1882              selected_method->is_private()  ? "private "  : "");
1883     selected_method->print_external_name(&ss);
1884     ss.print("'.");
1885   }
1886 
1887   THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
1888 }