1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   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.
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   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
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  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
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  24 
  25 #ifndef SHARE_VM_INTERPRETER_LINKRESOLVER_HPP
  26 #define SHARE_VM_INTERPRETER_LINKRESOLVER_HPP
  27 
  28 #include "oops/method.hpp"
  29 
  30 // All the necessary definitions for run-time link resolution.
  31 
  32 // CallInfo provides all the information gathered for a particular
  33 // linked call site after resolving it. A link is any reference
  34 // made from within the bytecodes of a method to an object outside of
  35 // that method. If the info is invalid, the link has not been resolved
  36 // successfully.
  37 
  38 class CallInfo : public StackObj {
  39  public:
  40   // Ways that a method call might be selected (or not) based on receiver type.
  41   // Note that an invokevirtual instruction might be linked with no_dispatch,
  42   // and an invokeinterface instruction might be linked with any of the three options
  43   enum CallKind {
  44     direct_call,                        // jump into resolved_method (must be concrete)
  45     vtable_call,                        // select recv.klass.method_at_vtable(index)
  46     itable_call,                        // select recv.klass.method_at_itable(resolved_method.holder, index)
  47     unknown_kind = -1
  48   };
  49  private:
  50   KlassHandle  _resolved_klass;         // static receiver klass, resolved from a symbolic reference
  51   KlassHandle  _selected_klass;         // dynamic receiver class (same as static, or subklass)
  52   methodHandle _resolved_method;        // static target method
  53   methodHandle _selected_method;        // dynamic (actual) target method
  54   CallKind     _call_kind;              // kind of call (static(=bytecode static/special +
  55                                         //               others inferred), vtable, itable)
  56   int          _call_index;             // vtable or itable index of selected class method (if any)
  57   Handle       _resolved_appendix;      // extra argument in constant pool (if CPCE::has_appendix)
  58   Handle       _resolved_method_type;   // MethodType (for invokedynamic and invokehandle call sites)
  59 
  60   void set_static(KlassHandle resolved_klass, const methodHandle& resolved_method, TRAPS);
  61   void set_interface(KlassHandle resolved_klass, KlassHandle selected_klass,
  62                      const methodHandle& resolved_method,
  63                      const methodHandle& selected_method,
  64                      int itable_index, TRAPS);
  65   void set_virtual(KlassHandle resolved_klass, KlassHandle selected_klass,
  66                    const methodHandle& resolved_method,
  67                    const methodHandle& selected_method,
  68                    int vtable_index, TRAPS);
  69   void set_handle(const methodHandle& resolved_method,
  70                   Handle resolved_appendix, Handle resolved_method_type, TRAPS);
  71   void set_handle(KlassHandle resolved_klass,
  72                   const methodHandle& resolved_method,
  73                   Handle resolved_appendix, Handle resolved_method_type, TRAPS);
  74   void set_common(KlassHandle resolved_klass, KlassHandle selected_klass,
  75                   const methodHandle& resolved_method,
  76                   const methodHandle& selected_method,
  77                   CallKind kind,
  78                   int index, TRAPS);
  79 
  80   friend class LinkResolver;
  81 
  82  public:
  83   CallInfo() {
  84 #ifndef PRODUCT
  85     _call_kind  = CallInfo::unknown_kind;
  86     _call_index = Method::garbage_vtable_index;
  87 #endif //PRODUCT
  88   }
  89 
  90   // utility to extract an effective CallInfo from a method and an optional receiver limit
  91   // does not queue the method for compilation
  92   CallInfo(Method* resolved_method, Klass* resolved_klass = NULL);
  93 
  94   KlassHandle  resolved_klass() const            { return _resolved_klass; }
  95   KlassHandle  selected_klass() const            { return _selected_klass; }
  96   methodHandle resolved_method() const           { return _resolved_method; }
  97   methodHandle selected_method() const           { return _selected_method; }
  98   Handle       resolved_appendix() const         { return _resolved_appendix; }
  99   Handle       resolved_method_type() const      { return _resolved_method_type; }
 100 
 101   BasicType    result_type() const               { return selected_method()->result_type(); }
 102   CallKind     call_kind() const                 { return _call_kind; }
 103   int          call_index() const                { return _call_index; }
 104   int          vtable_index() const {
 105     // Even for interface calls the vtable index could be non-negative.
 106     // See CallInfo::set_interface.
 107     assert(has_vtable_index() || is_statically_bound(), "");
 108     assert(call_kind() == vtable_call || call_kind() == direct_call, "");
 109     // The returned value is < 0 if the call is statically bound.
 110     // But, the returned value may be >= 0 even if the kind is direct_call.
 111     // It is up to the caller to decide which way to go.
 112     return _call_index;
 113   }
 114   int          itable_index() const {
 115     assert(call_kind() == itable_call, "");
 116     // The returned value is always >= 0, a valid itable index.
 117     return _call_index;
 118   }
 119 
 120   // debugging
 121 #ifdef ASSERT
 122   bool         has_vtable_index() const          { return _call_index >= 0 && _call_kind != CallInfo::itable_call; }
 123   bool         is_statically_bound() const       { return _call_index == Method::nonvirtual_vtable_index; }
 124 #endif //ASSERT
 125   void         verify() PRODUCT_RETURN;
 126   void         print()  PRODUCT_RETURN;
 127 };
 128 
 129 
 130 // Condensed information from constant pool to use to resolve the method or field.
 131 //   resolved_klass = specified class (i.e., static receiver class)
 132 //   current_klass  = sending method holder (i.e., class containing the method
 133 //                    containing the call being resolved)
 134 //   current_method = sending method (relevant for field resolution)
 135 class LinkInfo : public StackObj {
 136   Symbol*      _name;            // extracted from JVM_CONSTANT_NameAndType
 137   Symbol*      _signature;
 138   KlassHandle  _resolved_klass;  // class that the constant pool entry points to
 139   KlassHandle  _current_klass;   // class that owns the constant pool
 140   methodHandle _current_method;  // sending method
 141   bool         _check_access;
 142  public:
 143   LinkInfo(const constantPoolHandle& pool, int index, methodHandle current_method, TRAPS);
 144   // Condensed information from other call sites within the vm.
 145   LinkInfo(KlassHandle resolved_klass,
 146            Symbol* name, Symbol* signature, // field or method signature
 147            KlassHandle current_klass, methodHandle current_method,
 148            bool check_access = true) :
 149     _resolved_klass(resolved_klass),
 150     _name(name), _signature(signature),
 151     _current_klass(current_klass), _current_method(current_method),
 152     _check_access(check_access) {}
 153 
 154   // accessors
 155   Symbol* name() const                { return _name; }
 156   Symbol* signature() const           { return _signature; }
 157   KlassHandle resolved_klass() const  { return _resolved_klass; }
 158   KlassHandle current_klass() const   { return _current_klass; }
 159   methodHandle current_method() const { return _current_method; }
 160   bool check_access() const           { return _check_access; }
 161   char* method_string() const;
 162 
 163   void         print()  PRODUCT_RETURN;
 164 };
 165 
 166 // Link information for getfield/putfield & getstatic/putstatic bytecodes
 167 // is represented using a fieldDescriptor.
 168 
 169 // The LinkResolver is used to resolve constant-pool references at run-time.
 170 // It does all necessary link-time checks & throws exceptions if necessary.
 171 
 172 class LinkResolver: AllStatic {
 173   friend class klassVtable;
 174   friend class klassItable;
 175 
 176  private:
 177 
 178   static methodHandle lookup_method_in_klasses(const LinkInfo& link_info,
 179                                                bool checkpolymorphism,
 180                                                bool in_imethod_resolve, TRAPS);
 181   static methodHandle lookup_method_in_interfaces(const LinkInfo& link_info, TRAPS);
 182   static methodHandle lookup_polymorphic_method(const LinkInfo& link_info,
 183                                                 Handle *appendix_result_or_null,
 184                                                 Handle *method_type_result, TRAPS);
 185  JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod()
 186   // Not Linktime so doesn't take LinkInfo
 187   static methodHandle lookup_instance_method_in_klasses (
 188                                        KlassHandle klass, Symbol* name, Symbol* signature, TRAPS);
 189  JVMCI_ONLY(private:)
 190 
 191   // Similar loader constraint checking functions that throw
 192   // LinkageError with descriptive message.
 193   static void check_method_loader_constraints(const LinkInfo& link_info,
 194                                               const methodHandle& resolved_method,
 195                                               const char* method_type, TRAPS);
 196   static void check_field_loader_constraints(Symbol* field, Symbol* sig,
 197                                              KlassHandle current_klass,
 198                                              KlassHandle sel_klass, TRAPS);
 199 
 200   static methodHandle resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS);
 201   static methodHandle resolve_method          (const LinkInfo& link_info, bool require_methodref, TRAPS);
 202 
 203   static methodHandle linktime_resolve_static_method    (const LinkInfo& link_info, TRAPS);
 204   static methodHandle linktime_resolve_special_method   (const LinkInfo& link_info, TRAPS);
 205   static methodHandle linktime_resolve_virtual_method   (const LinkInfo& link_info, TRAPS);
 206   static methodHandle linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS);
 207 
 208   static void runtime_resolve_special_method    (CallInfo& result,
 209                                                  const methodHandle& resolved_method,
 210                                                  KlassHandle resolved_klass,
 211                                                  KlassHandle current_klass,
 212                                                  bool check_access, TRAPS);
 213   static void runtime_resolve_virtual_method    (CallInfo& result,
 214                                                  const methodHandle& resolved_method,
 215                                                  KlassHandle resolved_klass,
 216                                                  Handle recv,
 217                                                  KlassHandle recv_klass,
 218                                                  bool check_null_and_abstract, TRAPS);
 219   static void runtime_resolve_interface_method  (CallInfo& result,
 220                                                  const methodHandle& resolved_method,
 221                                                  KlassHandle resolved_klass,
 222                                                  Handle recv,
 223                                                  KlassHandle recv_klass,
 224                                                  bool check_null_and_abstract, TRAPS);
 225 
 226   static void check_field_accessability(KlassHandle ref_klass,
 227                                         KlassHandle resolved_klass,
 228                                         KlassHandle sel_klass,
 229                                         const fieldDescriptor& fd, TRAPS);
 230   static void check_method_accessability(KlassHandle ref_klass,
 231                                          KlassHandle resolved_klass,
 232                                          KlassHandle sel_klass,
 233                                          const methodHandle& sel_method, TRAPS);
 234 
 235   // runtime resolving from constant pool
 236   static void resolve_invokestatic   (CallInfo& result,
 237                                       const constantPoolHandle& pool, int index, TRAPS);
 238   static void resolve_invokespecial  (CallInfo& result,
 239                                       const constantPoolHandle& pool, int index, TRAPS);
 240   static void resolve_invokevirtual  (CallInfo& result, Handle recv,
 241                                       const constantPoolHandle& pool, int index, TRAPS);
 242   static void resolve_invokeinterface(CallInfo& result, Handle recv,
 243                                       const constantPoolHandle& pool, int index, TRAPS);
 244   static void resolve_invokedynamic  (CallInfo& result,
 245                                       const constantPoolHandle& pool, int index, TRAPS);
 246   static void resolve_invokehandle   (CallInfo& result,
 247                                       const constantPoolHandle& pool, int index, TRAPS);
 248  public:
 249   // constant pool resolving
 250   static void check_klass_accessability(KlassHandle ref_klass, KlassHandle sel_klass, TRAPS);
 251 
 252   // static resolving calls (will not run any Java code);
 253   // used only from Bytecode_invoke::static_target
 254   static methodHandle resolve_method_statically(Bytecodes::Code code,
 255                                                 const constantPoolHandle& pool,
 256                                                 int index, TRAPS);
 257 
 258   static void resolve_field_access(fieldDescriptor& result,
 259                                    const constantPoolHandle& pool,
 260                                    int index,
 261                                    const methodHandle& method,
 262                                    Bytecodes::Code byte, TRAPS);
 263   static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info,
 264                             Bytecodes::Code access_kind,
 265                             bool initialize_class, TRAPS);
 266 
 267   static void resolve_static_call   (CallInfo& result,
 268                                      const LinkInfo& link_info,
 269                                      bool initialize_klass, TRAPS);
 270   static void resolve_special_call  (CallInfo& result,
 271                                      const LinkInfo& link_info,
 272                                      TRAPS);
 273   static void resolve_virtual_call  (CallInfo& result, Handle recv, KlassHandle recv_klass,
 274                                      const LinkInfo& link_info,
 275                                      bool check_null_and_abstract, TRAPS);
 276   static void resolve_interface_call(CallInfo& result, Handle recv, KlassHandle recv_klass,
 277                                      const LinkInfo& link_info,
 278                                      bool check_null_and_abstract, TRAPS);
 279   static void resolve_handle_call   (CallInfo& result,
 280                                      const LinkInfo& link_info, TRAPS);
 281   static void resolve_dynamic_call  (CallInfo& result, Handle bootstrap_specifier,
 282                                      Symbol* method_name, Symbol* method_signature,
 283                                      KlassHandle current_klass, TRAPS);
 284 
 285   // same as above for compile-time resolution; but returns null handle instead of throwing
 286   // an exception on error also, does not initialize klass (i.e., no side effects)
 287   static methodHandle resolve_virtual_call_or_null  (KlassHandle receiver_klass,
 288                                                      const LinkInfo& link_info);
 289   static methodHandle resolve_interface_call_or_null(KlassHandle receiver_klass,
 290                                                      const LinkInfo& link_info);
 291   static methodHandle resolve_static_call_or_null   (const LinkInfo& link_info);
 292   static methodHandle resolve_special_call_or_null  (const LinkInfo& link_info);
 293 
 294   static int vtable_index_of_interface_method(KlassHandle klass, const methodHandle& resolved_method);
 295 
 296   // same as above for compile-time resolution; returns vtable_index if current_klass if linked
 297   static int resolve_virtual_vtable_index  (KlassHandle receiver_klass,
 298                                             const LinkInfo& link_info);
 299 
 300   // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful)
 301   static methodHandle linktime_resolve_virtual_method_or_null  (const LinkInfo& link_info);
 302   static methodHandle linktime_resolve_interface_method_or_null(const LinkInfo& link_info);
 303 
 304   // runtime resolving from constant pool
 305   static void resolve_invoke(CallInfo& result, Handle recv,
 306                              const constantPoolHandle& pool, int index,
 307                              Bytecodes::Code byte, TRAPS);
 308 
 309   // runtime resolving from attached method
 310   static void resolve_invoke(CallInfo& result, Handle& recv,
 311                              const methodHandle& attached_method,
 312                              Bytecodes::Code byte, TRAPS);
 313 };
 314 #endif // SHARE_VM_INTERPRETER_LINKRESOLVER_HPP
--- EOF ---