1 /* 2 * Copyright (c) 1997, 2024, 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(Klass* resolved_klass, 70 const methodHandle& resolved_method, 71 Handle resolved_appendix, TRAPS); 72 void set_common(Klass* resolved_klass, 73 const methodHandle& resolved_method, 74 const methodHandle& selected_method, 75 CallKind kind, 76 int index, TRAPS); 77 78 friend class BootstrapInfo; 79 friend class LinkResolver; 80 81 public: 82 CallInfo() { 83 #ifndef PRODUCT 84 _call_kind = CallInfo::unknown_kind; 85 _call_index = Method::garbage_vtable_index; 86 #endif //PRODUCT 87 } 88 89 // utility to extract an effective CallInfo from a method and an optional receiver limit 90 // does not queue the method for compilation. This also creates a ResolvedMethodName 91 // object for the resolved_method. 92 CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS); 93 94 Klass* resolved_klass() const { return _resolved_klass; } 95 Method* resolved_method() const; 96 Method* selected_method() const; 97 Handle resolved_appendix() const { return _resolved_appendix; } 98 Handle resolved_method_name() const { return _resolved_method_name; } 99 // Materialize a java.lang.invoke.ResolvedMethodName for this resolved_method 100 void set_resolved_method_name(TRAPS); 101 102 BasicType result_type() const { return selected_method()->result_type(); } 103 CallKind call_kind() const { return _call_kind; } 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 Klass* _resolved_klass; // class that the constant pool entry points to 139 Klass* _current_klass; // class that owns the constant pool 140 methodHandle _current_method; // sending method 141 bool _check_access; 142 bool _check_loader_constraints; 143 constantTag _tag; 144 145 public: 146 enum class AccessCheck { required, skip }; 147 enum class LoaderConstraintCheck { required, skip }; 148 149 LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, Bytecodes::Code code, TRAPS); 150 LinkInfo(const constantPoolHandle& pool, int index, Bytecodes::Code code, TRAPS); 151 152 // Condensed information from other call sites within the vm. 153 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, Klass* current_klass, 154 AccessCheck check_access = AccessCheck::required, 155 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required, 156 constantTag tag = JVM_CONSTANT_Invalid) : 157 _name(name), 158 _signature(signature), 159 _resolved_klass(resolved_klass), 160 _current_klass(current_klass), 161 _current_method(methodHandle()), 162 _check_access(check_access == AccessCheck::required), 163 _check_loader_constraints(check_loader_constraints == LoaderConstraintCheck::required), 164 _tag(tag) { 165 assert(_resolved_klass != nullptr, "must always have a resolved_klass"); 166 } 167 168 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, const methodHandle& current_method, 169 AccessCheck check_access = AccessCheck::required, 170 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required, 171 constantTag tag = JVM_CONSTANT_Invalid) : 172 LinkInfo(resolved_klass, name, signature, current_method->method_holder(), check_access, check_loader_constraints, tag) { 173 _current_method = current_method; 174 } 175 176 // Case where we just find the method and don't check access against the current class, used by JavaCalls 177 LinkInfo(Klass* resolved_klass, Symbol*name, Symbol* signature) : 178 LinkInfo(resolved_klass, name, signature, nullptr, AccessCheck::skip, LoaderConstraintCheck::skip, 179 JVM_CONSTANT_Invalid) {} 180 181 // accessors 182 Symbol* name() const { return _name; } 183 Symbol* signature() const { return _signature; } 184 Klass* resolved_klass() const { return _resolved_klass; } 185 Klass* current_klass() const { return _current_klass; } 186 Method* current_method() const { return _current_method(); } 187 constantTag tag() const { return _tag; } 188 bool check_access() const { return _check_access; } 189 bool check_loader_constraints() const { return _check_loader_constraints; } 190 void print() PRODUCT_RETURN; 191 }; 192 193 // Link information for getfield/putfield & getstatic/putstatic bytecodes 194 // is represented using a fieldDescriptor. 195 196 // The LinkResolver is used to resolve constant-pool references at run-time. 197 // It does all necessary link-time checks & throws exceptions if necessary. 198 199 class LinkResolver: AllStatic { 200 friend class klassVtable; 201 friend class klassItable; 202 203 private: 204 205 static Method* lookup_method_in_klasses(const LinkInfo& link_info, 206 bool checkpolymorphism, 207 bool in_imethod_resolve); 208 static Method* lookup_method_in_interfaces(const LinkInfo& link_info); 209 210 static Method* lookup_polymorphic_method(const LinkInfo& link_info, 211 Handle *appendix_result_or_null, TRAPS); 212 JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod() 213 // Not Linktime so doesn't take LinkInfo 214 static Method* lookup_instance_method_in_klasses (Klass* klass, Symbol* name, Symbol* signature, 215 Klass::PrivateLookupMode private_mode); 216 JVMCI_ONLY(private:) 217 218 // Similar loader constraint checking functions that throw 219 // LinkageError with descriptive message. 220 static void check_method_loader_constraints(const LinkInfo& link_info, 221 const methodHandle& resolved_method, 222 const char* method_type, TRAPS); 223 static void check_field_loader_constraints(Symbol* field, Symbol* sig, 224 Klass* current_klass, 225 Klass* sel_klass, TRAPS); 226 227 static Method* resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 228 static Method* resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 229 230 static Method* linktime_resolve_static_method (const LinkInfo& link_info, TRAPS); 231 static Method* linktime_resolve_special_method (const LinkInfo& link_info, TRAPS); 232 static Method* linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS); 233 static Method* linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS); 234 235 static void runtime_resolve_special_method (CallInfo& result, 236 const LinkInfo& link_info, 237 const methodHandle& resolved_method, 238 Handle recv, TRAPS); 239 240 static void runtime_resolve_virtual_method (CallInfo& result, 241 const methodHandle& resolved_method, 242 Klass* resolved_klass, 243 Handle recv, 244 Klass* recv_klass, 245 bool check_null_and_abstract, TRAPS); 246 static void runtime_resolve_interface_method (CallInfo& result, 247 const methodHandle& resolved_method, 248 Klass* resolved_klass, 249 Handle recv, 250 Klass* recv_klass, 251 bool check_null_and_abstract, TRAPS); 252 253 static bool resolve_previously_linked_invokehandle(CallInfo& result, 254 const LinkInfo& link_info, 255 const constantPoolHandle& pool, 256 int index, TRAPS); 257 258 static void check_field_accessability(Klass* ref_klass, 259 Klass* resolved_klass, 260 Klass* sel_klass, 261 const fieldDescriptor& fd, TRAPS); 262 static void check_method_accessability(Klass* ref_klass, 263 Klass* resolved_klass, 264 Klass* sel_klass, 265 const methodHandle& sel_method, TRAPS); 266 267 // runtime resolving from constant pool 268 static void resolve_invokestatic (CallInfo& result, 269 const constantPoolHandle& pool, int index, TRAPS); 270 static void resolve_invokespecial (CallInfo& result, Handle recv, 271 const constantPoolHandle& pool, int index, TRAPS); 272 static void resolve_invokevirtual (CallInfo& result, Handle recv, 273 const constantPoolHandle& pool, int index, TRAPS); 274 static void resolve_invokeinterface(CallInfo& result, Handle recv, 275 const constantPoolHandle& pool, int index, TRAPS); 276 static void resolve_invokedynamic (CallInfo& result, 277 const constantPoolHandle& pool, int index, TRAPS); 278 static void resolve_invokehandle (CallInfo& result, 279 const constantPoolHandle& pool, int index, TRAPS); 280 public: 281 // constant pool resolving 282 static void check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS); 283 284 // static resolving calls (will not run any Java code); 285 // used only from Bytecode_invoke::static_target 286 static Method* resolve_method_statically(Bytecodes::Code code, 287 const constantPoolHandle& pool, 288 int index, TRAPS); 289 290 static void resolve_continuation_enter(CallInfo& callinfo, TRAPS); 291 292 static void resolve_field_access(fieldDescriptor& result, 293 const constantPoolHandle& pool, 294 int index, 295 const methodHandle& method, 296 Bytecodes::Code byte, 297 bool initialize_class, TRAPS); 298 static void resolve_field_access(fieldDescriptor& result, 299 const constantPoolHandle& pool, 300 int index, 301 const methodHandle& method, 302 Bytecodes::Code byte, TRAPS) { 303 resolve_field_access(result, pool, index, method, byte, 304 /* initialize_class*/true, THREAD); 305 } 306 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info, 307 Bytecodes::Code access_kind, 308 bool initialize_class, TRAPS); 309 310 static void resolve_static_call (CallInfo& result, 311 const LinkInfo& link_info, 312 bool initialize_klass, TRAPS); 313 static void resolve_special_call (CallInfo& result, 314 Handle recv, 315 const LinkInfo& link_info, 316 TRAPS); 317 static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass, 318 const LinkInfo& link_info, 319 bool check_null_and_abstract, TRAPS); 320 static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass, 321 const LinkInfo& link_info, 322 bool check_null_and_abstract, TRAPS); 323 static void resolve_handle_call (CallInfo& result, 324 const LinkInfo& link_info, TRAPS); 325 static void resolve_dynamic_call (CallInfo& result, 326 BootstrapInfo& bootstrap_specifier, TRAPS); 327 328 // same as above for compile-time resolution; but returns null handle instead of throwing 329 // an exception on error also, does not initialize klass (i.e., no side effects) 330 static Method* resolve_virtual_call_or_null(Klass* receiver_klass, 331 const LinkInfo& link_info); 332 static Method* resolve_interface_call_or_null(Klass* receiver_klass, 333 const LinkInfo& link_info); 334 static Method* resolve_static_call_or_null(const LinkInfo& link_info); 335 static Method* resolve_special_call_or_null(const LinkInfo& link_info); 336 337 static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method); 338 339 // same as above for compile-time resolution; returns vtable_index if current_klass if linked 340 static int resolve_virtual_vtable_index (Klass* receiver_klass, 341 const LinkInfo& link_info); 342 343 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful) 344 static Method* linktime_resolve_virtual_method_or_null (const LinkInfo& link_info); 345 static Method* linktime_resolve_interface_method_or_null(const LinkInfo& link_info); 346 347 // runtime resolving from constant pool 348 static void resolve_invoke(CallInfo& result, Handle recv, 349 const constantPoolHandle& pool, int index, 350 Bytecodes::Code byte, TRAPS); 351 352 // runtime resolving from attached method 353 static void resolve_invoke(CallInfo& result, Handle& recv, 354 const methodHandle& attached_method, 355 Bytecodes::Code byte, TRAPS); 356 357 // Only resolved method known. 358 static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) { 359 throw_abstract_method_error(resolved_method, methodHandle(), nullptr, CHECK); 360 } 361 // Resolved method and receiver klass know. 362 static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) { 363 throw_abstract_method_error(resolved_method, methodHandle(), recv_klass, CHECK); 364 } 365 // Selected method is abstract. 366 static void throw_abstract_method_error(const methodHandle& resolved_method, 367 const methodHandle& selected_method, 368 Klass *recv_klass, TRAPS); 369 }; 370 #endif // SHARE_INTERPRETER_LINKRESOLVER_HPP