1 /* 2 * Copyright (c) 1997, 2015, 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 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