1 /* 2 * Copyright (c) 1997, 2021, 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 #ifndef SHARE_INTERPRETER_LINKRESOLVER_HPP 26 #define SHARE_INTERPRETER_LINKRESOLVER_HPP 27 28 #include "interpreter/bootstrapInfo.hpp" 29 #include "oops/method.hpp" 30 31 // All the necessary definitions for run-time link resolution. 32 33 // CallInfo provides all the information gathered for a particular 34 // linked call site after resolving it. A link is any reference 35 // made from within the bytecodes of a method to an object outside of 36 // that method. If the info is invalid, the link has not been resolved 37 // successfully. 38 39 class CallInfo : public StackObj { 40 public: 41 // Ways that a method call might be selected (or not) based on receiver type. 42 // Note that an invokevirtual instruction might be linked with no_dispatch, 43 // and an invokeinterface instruction might be linked with any of the three options 44 enum CallKind { 45 direct_call, // jump into resolved_method (must be concrete) 46 vtable_call, // select recv.klass.method_at_vtable(index) 47 itable_call, // select recv.klass.method_at_itable(resolved_method.holder, index) 48 unknown_kind = -1 49 }; 50 private: 51 Klass* _resolved_klass; // static receiver klass, resolved from a symbolic reference 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_name; // Object holding the ResolvedMethodName 59 60 void set_static(Klass* resolved_klass, const methodHandle& resolved_method, TRAPS); 61 void set_interface(Klass* resolved_klass, 62 const methodHandle& resolved_method, 63 const methodHandle& selected_method, 64 int itable_index, TRAPS); 65 void set_virtual(Klass* resolved_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, TRAPS); 71 void set_handle(Klass* resolved_klass, 72 const methodHandle& resolved_method, 73 Handle resolved_appendix, TRAPS); 74 void set_common(Klass* resolved_klass, 75 const methodHandle& resolved_method, 76 const methodHandle& selected_method, 77 CallKind kind, 78 int index, TRAPS); 79 80 friend class BootstrapInfo; 81 friend class LinkResolver; 82 83 public: CallInfo()84 CallInfo() { 85 #ifndef PRODUCT 86 _call_kind = CallInfo::unknown_kind; 87 _call_index = Method::garbage_vtable_index; 88 #endif //PRODUCT 89 } 90 91 // utility to extract an effective CallInfo from a method and an optional receiver limit 92 // does not queue the method for compilation. This also creates a ResolvedMethodName 93 // object for the resolved_method. 94 CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS); 95 resolved_klass() const96 Klass* resolved_klass() const { return _resolved_klass; } resolved_method() const97 Method* resolved_method() const { return _resolved_method(); } selected_method() const98 Method* selected_method() const { return _selected_method(); } resolved_appendix() const99 Handle resolved_appendix() const { return _resolved_appendix; } resolved_method_name() const100 Handle resolved_method_name() const { return _resolved_method_name; } 101 // Materialize a java.lang.invoke.ResolvedMethodName for this resolved_method 102 void set_resolved_method_name(TRAPS); 103 result_type() const104 BasicType result_type() const { return selected_method()->result_type(); } call_kind() const105 CallKind call_kind() const { return _call_kind; } vtable_index() const106 int vtable_index() const { 107 // Even for interface calls the vtable index could be non-negative. 108 // See CallInfo::set_interface. 109 assert(has_vtable_index() || is_statically_bound(), ""); 110 assert(call_kind() == vtable_call || call_kind() == direct_call, ""); 111 // The returned value is < 0 if the call is statically bound. 112 // But, the returned value may be >= 0 even if the kind is direct_call. 113 // It is up to the caller to decide which way to go. 114 return _call_index; 115 } itable_index() const116 int itable_index() const { 117 assert(call_kind() == itable_call, ""); 118 // The returned value is always >= 0, a valid itable index. 119 return _call_index; 120 } 121 122 // debugging 123 #ifdef ASSERT has_vtable_index() const124 bool has_vtable_index() const { return _call_index >= 0 && _call_kind != CallInfo::itable_call; } is_statically_bound() const125 bool is_statically_bound() const { return _call_index == Method::nonvirtual_vtable_index; } 126 #endif //ASSERT 127 void verify() PRODUCT_RETURN; 128 void print() PRODUCT_RETURN; 129 }; 130 131 132 // Condensed information from constant pool to use to resolve the method or field. 133 // resolved_klass = specified class (i.e., static receiver class) 134 // current_klass = sending method holder (i.e., class containing the method 135 // containing the call being resolved) 136 // current_method = sending method (relevant for field resolution) 137 class LinkInfo : public StackObj { 138 Symbol* _name; // extracted from JVM_CONSTANT_NameAndType 139 Symbol* _signature; 140 Klass* _resolved_klass; // class that the constant pool entry points to 141 Klass* _current_klass; // class that owns the constant pool 142 methodHandle _current_method; // sending method 143 bool _check_access; 144 bool _check_loader_constraints; 145 constantTag _tag; 146 147 public: 148 enum class AccessCheck { required, skip }; 149 enum class LoaderConstraintCheck { required, skip }; 150 151 LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, TRAPS); 152 LinkInfo(const constantPoolHandle& pool, int index, TRAPS); 153 154 // Condensed information from other call sites within the vm. LinkInfo(Klass * resolved_klass,Symbol * name,Symbol * signature,Klass * current_klass,AccessCheck check_access=AccessCheck::required,LoaderConstraintCheck check_loader_constraints=LoaderConstraintCheck::required,constantTag tag=JVM_CONSTANT_Invalid)155 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, Klass* current_klass, 156 AccessCheck check_access = AccessCheck::required, 157 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required, 158 constantTag tag = JVM_CONSTANT_Invalid) : 159 _name(name), 160 _signature(signature), _resolved_klass(resolved_klass), _current_klass(current_klass), _current_method(methodHandle()), 161 _check_access(check_access == AccessCheck::required), 162 _check_loader_constraints(check_loader_constraints == LoaderConstraintCheck::required), _tag(tag) {} 163 LinkInfo(Klass * resolved_klass,Symbol * name,Symbol * signature,const methodHandle & current_method,AccessCheck check_access=AccessCheck::required,LoaderConstraintCheck check_loader_constraints=LoaderConstraintCheck::required,constantTag tag=JVM_CONSTANT_Invalid)164 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, const methodHandle& current_method, 165 AccessCheck check_access = AccessCheck::required, 166 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required, 167 constantTag tag = JVM_CONSTANT_Invalid) : 168 _name(name), 169 _signature(signature), _resolved_klass(resolved_klass), _current_klass(current_method->method_holder()), _current_method(current_method), 170 _check_access(check_access == AccessCheck::required), 171 _check_loader_constraints(check_loader_constraints == LoaderConstraintCheck::required), _tag(tag) {} 172 173 174 // Case where we just find the method and don't check access against the current class LinkInfo(Klass * resolved_klass,Symbol * name,Symbol * signature)175 LinkInfo(Klass* resolved_klass, Symbol*name, Symbol* signature) : 176 _name(name), 177 _signature(signature), _resolved_klass(resolved_klass), _current_klass(NULL), _current_method(methodHandle()), 178 _check_access(false), _check_loader_constraints(false), _tag(JVM_CONSTANT_Invalid) {} 179 180 // accessors name() const181 Symbol* name() const { return _name; } signature() const182 Symbol* signature() const { return _signature; } resolved_klass() const183 Klass* resolved_klass() const { return _resolved_klass; } current_klass() const184 Klass* current_klass() const { return _current_klass; } current_method() const185 Method* current_method() const { return _current_method(); } tag() const186 constantTag tag() const { return _tag; } check_access() const187 bool check_access() const { return _check_access; } check_loader_constraints() const188 bool check_loader_constraints() const { return _check_loader_constraints; } 189 void print() PRODUCT_RETURN; 190 }; 191 192 // Link information for getfield/putfield & getstatic/putstatic bytecodes 193 // is represented using a fieldDescriptor. 194 195 // The LinkResolver is used to resolve constant-pool references at run-time. 196 // It does all necessary link-time checks & throws exceptions if necessary. 197 198 class LinkResolver: AllStatic { 199 friend class klassVtable; 200 friend class klassItable; 201 202 private: 203 204 static Method* lookup_method_in_klasses(const LinkInfo& link_info, 205 bool checkpolymorphism, 206 bool in_imethod_resolve); 207 static Method* lookup_method_in_interfaces(const LinkInfo& link_info); 208 209 static Method* lookup_polymorphic_method(const LinkInfo& link_info, 210 Handle *appendix_result_or_null, TRAPS); 211 JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod() 212 // Not Linktime so doesn't take LinkInfo 213 static Method* lookup_instance_method_in_klasses (Klass* klass, Symbol* name, Symbol* signature, 214 Klass::PrivateLookupMode private_mode); 215 JVMCI_ONLY(private:) 216 217 // Similar loader constraint checking functions that throw 218 // LinkageError with descriptive message. 219 static void check_method_loader_constraints(const LinkInfo& link_info, 220 const methodHandle& resolved_method, 221 const char* method_type, TRAPS); 222 static void check_field_loader_constraints(Symbol* field, Symbol* sig, 223 Klass* current_klass, 224 Klass* sel_klass, TRAPS); 225 226 static Method* resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 227 static Method* resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 228 229 static Method* linktime_resolve_static_method (const LinkInfo& link_info, TRAPS); 230 static Method* linktime_resolve_special_method (const LinkInfo& link_info, TRAPS); 231 static Method* linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS); 232 static Method* linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS); 233 234 static void runtime_resolve_special_method (CallInfo& result, 235 const LinkInfo& link_info, 236 const methodHandle& resolved_method, 237 Handle recv, TRAPS); 238 239 static void runtime_resolve_virtual_method (CallInfo& result, 240 const methodHandle& resolved_method, 241 Klass* resolved_klass, 242 Handle recv, 243 Klass* recv_klass, 244 bool check_null_and_abstract, TRAPS); 245 static void runtime_resolve_interface_method (CallInfo& result, 246 const methodHandle& resolved_method, 247 Klass* resolved_klass, 248 Handle recv, 249 Klass* recv_klass, 250 bool check_null_and_abstract, TRAPS); 251 252 static void check_field_accessability(Klass* ref_klass, 253 Klass* resolved_klass, 254 Klass* sel_klass, 255 const fieldDescriptor& fd, TRAPS); 256 static void check_method_accessability(Klass* ref_klass, 257 Klass* resolved_klass, 258 Klass* sel_klass, 259 const methodHandle& sel_method, TRAPS); 260 261 // runtime resolving from constant pool 262 static void resolve_invokestatic (CallInfo& result, 263 const constantPoolHandle& pool, int index, TRAPS); 264 static void resolve_invokespecial (CallInfo& result, Handle recv, 265 const constantPoolHandle& pool, int index, TRAPS); 266 static void resolve_invokevirtual (CallInfo& result, Handle recv, 267 const constantPoolHandle& pool, int index, TRAPS); 268 static void resolve_invokeinterface(CallInfo& result, Handle recv, 269 const constantPoolHandle& pool, int index, TRAPS); 270 static void resolve_invokedynamic (CallInfo& result, 271 const constantPoolHandle& pool, int index, TRAPS); 272 static void resolve_invokehandle (CallInfo& result, 273 const constantPoolHandle& pool, int index, TRAPS); 274 public: 275 // constant pool resolving 276 static void check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS); 277 278 // static resolving calls (will not run any Java code); 279 // used only from Bytecode_invoke::static_target 280 static Method* resolve_method_statically(Bytecodes::Code code, 281 const constantPoolHandle& pool, 282 int index, TRAPS); 283 284 static void resolve_field_access(fieldDescriptor& result, 285 const constantPoolHandle& pool, 286 int index, 287 const methodHandle& method, 288 Bytecodes::Code byte, TRAPS); 289 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info, 290 Bytecodes::Code access_kind, 291 bool initialize_class, TRAPS); 292 293 static void resolve_static_call (CallInfo& result, 294 const LinkInfo& link_info, 295 bool initialize_klass, TRAPS); 296 static void resolve_special_call (CallInfo& result, 297 Handle recv, 298 const LinkInfo& link_info, 299 TRAPS); 300 static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass, 301 const LinkInfo& link_info, 302 bool check_null_and_abstract, TRAPS); 303 static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass, 304 const LinkInfo& link_info, 305 bool check_null_and_abstract, TRAPS); 306 static void resolve_handle_call (CallInfo& result, 307 const LinkInfo& link_info, TRAPS); 308 static void resolve_dynamic_call (CallInfo& result, 309 BootstrapInfo& bootstrap_specifier, TRAPS); 310 311 // same as above for compile-time resolution; but returns null handle instead of throwing 312 // an exception on error also, does not initialize klass (i.e., no side effects) 313 static Method* resolve_virtual_call_or_null(Klass* receiver_klass, 314 const LinkInfo& link_info); 315 static Method* resolve_interface_call_or_null(Klass* receiver_klass, 316 const LinkInfo& link_info); 317 static Method* resolve_static_call_or_null(const LinkInfo& link_info); 318 static Method* resolve_special_call_or_null(const LinkInfo& link_info); 319 320 static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method); 321 322 // same as above for compile-time resolution; returns vtable_index if current_klass if linked 323 static int resolve_virtual_vtable_index (Klass* receiver_klass, 324 const LinkInfo& link_info); 325 326 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful) 327 static Method* linktime_resolve_virtual_method_or_null (const LinkInfo& link_info); 328 static Method* linktime_resolve_interface_method_or_null(const LinkInfo& link_info); 329 330 // runtime resolving from constant pool 331 static void resolve_invoke(CallInfo& result, Handle recv, 332 const constantPoolHandle& pool, int index, 333 Bytecodes::Code byte, TRAPS); 334 335 // runtime resolving from attached method 336 static void resolve_invoke(CallInfo& result, Handle& recv, 337 const methodHandle& attached_method, 338 Bytecodes::Code byte, TRAPS); 339 340 public: 341 // Only resolved method known. throw_abstract_method_error(const methodHandle & resolved_method,TRAPS)342 static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) { 343 throw_abstract_method_error(resolved_method, methodHandle(), NULL, CHECK); 344 } 345 // Resolved method and receiver klass know. throw_abstract_method_error(const methodHandle & resolved_method,Klass * recv_klass,TRAPS)346 static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) { 347 throw_abstract_method_error(resolved_method, methodHandle(), recv_klass, CHECK); 348 } 349 // Selected method is abstract. 350 static void throw_abstract_method_error(const methodHandle& resolved_method, 351 const methodHandle& selected_method, 352 Klass *recv_klass, TRAPS); 353 }; 354 #endif // SHARE_INTERPRETER_LINKRESOLVER_HPP 355