1 /* 2 * Copyright (c) 1997, 2016, 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_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 constantTag _tag; 143 144 public: 145 enum AccessCheck { 146 needs_access_check, 147 skip_access_check 148 }; 149 150 LinkInfo(const constantPoolHandle& pool, int index, methodHandle current_method, TRAPS); 151 LinkInfo(const constantPoolHandle& pool, int index, TRAPS); 152 153 // Condensed information from other call sites within the vm. 154 LinkInfo(KlassHandle resolved_klass, Symbol* name, Symbol* signature, KlassHandle current_klass, 155 AccessCheck check_access = needs_access_check, 156 constantTag tag = JVM_CONSTANT_Invalid) : 157 _resolved_klass(resolved_klass), 158 _name(name), _signature(signature), _current_klass(current_klass), _current_method(NULL), 159 _check_access(check_access == needs_access_check), _tag(tag) {} 160 161 LinkInfo(KlassHandle resolved_klass, Symbol* name, Symbol* signature, methodHandle current_method, 162 AccessCheck check_access = needs_access_check, 163 constantTag tag = JVM_CONSTANT_Invalid) : 164 _resolved_klass(resolved_klass), 165 _name(name), _signature(signature), _current_klass(current_method->method_holder()), _current_method(current_method), 166 _check_access(check_access == needs_access_check), _tag(tag) {} 167 168 // Case where we just find the method and don't check access against the current class 169 LinkInfo(KlassHandle resolved_klass, Symbol*name, Symbol* signature) : 170 _resolved_klass(resolved_klass), 171 _name(name), _signature(signature), _current_klass(NULL), _current_method(NULL), 172 _check_access(false), _tag(JVM_CONSTANT_Invalid) {} 173 174 // accessors 175 Symbol* name() const { return _name; } 176 Symbol* signature() const { return _signature; } 177 KlassHandle resolved_klass() const { return _resolved_klass; } 178 KlassHandle current_klass() const { return _current_klass; } 179 methodHandle current_method() const { return _current_method; } 180 constantTag tag() const { return _tag; } 181 bool check_access() const { return _check_access; } 182 char* method_string() const; 183 184 void print() PRODUCT_RETURN; 185 }; 186 187 // Link information for getfield/putfield & getstatic/putstatic bytecodes 188 // is represented using a fieldDescriptor. 189 190 // The LinkResolver is used to resolve constant-pool references at run-time. 191 // It does all necessary link-time checks & throws exceptions if necessary. 192 193 class LinkResolver: AllStatic { 194 friend class klassVtable; 195 friend class klassItable; 196 197 private: 198 199 static methodHandle lookup_method_in_klasses(const LinkInfo& link_info, 200 bool checkpolymorphism, 201 bool in_imethod_resolve, TRAPS); 202 static methodHandle lookup_method_in_interfaces(const LinkInfo& link_info, TRAPS); 203 static methodHandle lookup_polymorphic_method(const LinkInfo& link_info, 204 Handle *appendix_result_or_null, 205 Handle *method_type_result, TRAPS); 206 JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod() 207 // Not Linktime so doesn't take LinkInfo 208 static methodHandle lookup_instance_method_in_klasses ( 209 KlassHandle klass, Symbol* name, Symbol* signature, TRAPS); 210 JVMCI_ONLY(private:) 211 212 // Similar loader constraint checking functions that throw 213 // LinkageError with descriptive message. 214 static void check_method_loader_constraints(const LinkInfo& link_info, 215 const methodHandle& resolved_method, 216 const char* method_type, TRAPS); 217 static void check_field_loader_constraints(Symbol* field, Symbol* sig, 218 KlassHandle current_klass, 219 KlassHandle sel_klass, TRAPS); 220 221 static methodHandle resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 222 static methodHandle resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS); 223 224 static methodHandle linktime_resolve_static_method (const LinkInfo& link_info, TRAPS); 225 static methodHandle linktime_resolve_special_method (const LinkInfo& link_info, TRAPS); 226 static methodHandle linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS); 227 static methodHandle linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS); 228 229 static void runtime_resolve_special_method (CallInfo& result, 230 const methodHandle& resolved_method, 231 KlassHandle resolved_klass, 232 KlassHandle current_klass, 233 bool check_access, TRAPS); 234 static void runtime_resolve_virtual_method (CallInfo& result, 235 const methodHandle& resolved_method, 236 KlassHandle resolved_klass, 237 Handle recv, 238 KlassHandle recv_klass, 239 bool check_null_and_abstract, TRAPS); 240 static void runtime_resolve_interface_method (CallInfo& result, 241 const methodHandle& resolved_method, 242 KlassHandle resolved_klass, 243 Handle recv, 244 KlassHandle recv_klass, 245 bool check_null_and_abstract, TRAPS); 246 247 static void check_field_accessability(KlassHandle ref_klass, 248 KlassHandle resolved_klass, 249 KlassHandle sel_klass, 250 const fieldDescriptor& fd, TRAPS); 251 static void check_method_accessability(KlassHandle ref_klass, 252 KlassHandle resolved_klass, 253 KlassHandle sel_klass, 254 const methodHandle& sel_method, TRAPS); 255 256 // runtime resolving from constant pool 257 static void resolve_invokestatic (CallInfo& result, 258 const constantPoolHandle& pool, int index, TRAPS); 259 static void resolve_invokespecial (CallInfo& result, 260 const constantPoolHandle& pool, int index, TRAPS); 261 static void resolve_invokevirtual (CallInfo& result, Handle recv, 262 const constantPoolHandle& pool, int index, TRAPS); 263 static void resolve_invokeinterface(CallInfo& result, Handle recv, 264 const constantPoolHandle& pool, int index, TRAPS); 265 static void resolve_invokedynamic (CallInfo& result, 266 const constantPoolHandle& pool, int index, TRAPS); 267 static void resolve_invokehandle (CallInfo& result, 268 const constantPoolHandle& pool, int index, TRAPS); 269 public: 270 // constant pool resolving 271 static void check_klass_accessability(KlassHandle ref_klass, KlassHandle sel_klass, TRAPS); 272 273 // static resolving calls (will not run any Java code); 274 // used only from Bytecode_invoke::static_target 275 static methodHandle resolve_method_statically(Bytecodes::Code code, 276 const constantPoolHandle& pool, 277 int index, TRAPS); 278 279 static void resolve_field_access(fieldDescriptor& result, 280 const constantPoolHandle& pool, 281 int index, 282 const methodHandle& method, 283 Bytecodes::Code byte, TRAPS); 284 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info, 285 Bytecodes::Code access_kind, 286 bool initialize_class, TRAPS); 287 288 static void resolve_static_call (CallInfo& result, 289 const LinkInfo& link_info, 290 bool initialize_klass, TRAPS); 291 static void resolve_special_call (CallInfo& result, 292 const LinkInfo& link_info, 293 TRAPS); 294 static void resolve_virtual_call (CallInfo& result, Handle recv, KlassHandle recv_klass, 295 const LinkInfo& link_info, 296 bool check_null_and_abstract, TRAPS); 297 static void resolve_interface_call(CallInfo& result, Handle recv, KlassHandle recv_klass, 298 const LinkInfo& link_info, 299 bool check_null_and_abstract, TRAPS); 300 static void resolve_handle_call (CallInfo& result, 301 const LinkInfo& link_info, TRAPS); 302 static void resolve_dynamic_call (CallInfo& result, Handle bootstrap_specifier, 303 Symbol* method_name, Symbol* method_signature, 304 KlassHandle current_klass, TRAPS); 305 306 // same as above for compile-time resolution; but returns null handle instead of throwing 307 // an exception on error also, does not initialize klass (i.e., no side effects) 308 static methodHandle resolve_virtual_call_or_null (KlassHandle receiver_klass, 309 const LinkInfo& link_info); 310 static methodHandle resolve_interface_call_or_null(KlassHandle receiver_klass, 311 const LinkInfo& link_info); 312 static methodHandle resolve_static_call_or_null (const LinkInfo& link_info); 313 static methodHandle resolve_special_call_or_null (const LinkInfo& link_info); 314 315 static int vtable_index_of_interface_method(KlassHandle klass, const methodHandle& resolved_method); 316 317 // same as above for compile-time resolution; returns vtable_index if current_klass if linked 318 static int resolve_virtual_vtable_index (KlassHandle receiver_klass, 319 const LinkInfo& link_info); 320 321 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful) 322 static methodHandle linktime_resolve_virtual_method_or_null (const LinkInfo& link_info); 323 static methodHandle linktime_resolve_interface_method_or_null(const LinkInfo& link_info); 324 325 // runtime resolving from constant pool 326 static void resolve_invoke(CallInfo& result, Handle recv, 327 const constantPoolHandle& pool, int index, 328 Bytecodes::Code byte, TRAPS); 329 330 // runtime resolving from attached method 331 static void resolve_invoke(CallInfo& result, Handle& recv, 332 const methodHandle& attached_method, 333 Bytecodes::Code byte, TRAPS); 334 }; 335 #endif // SHARE_VM_INTERPRETER_LINKRESOLVER_HPP