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
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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 CallKind call_kind() const { return _call_kind; }
103 int vtable_index() const {
104 // Even for interface calls the vtable index could be non-negative.
105 // See CallInfo::set_interface.
106 assert(has_vtable_index() || is_statically_bound(), "");
107 assert(call_kind() == vtable_call || call_kind() == direct_call, "");
108 // The returned value is < 0 if the call is statically bound.
109 // But, the returned value may be >= 0 even if the kind is direct_call.
110 // It is up to the caller to decide which way to go.
111 return _call_index;
112 }
113 int itable_index() const {
114 assert(call_kind() == itable_call, "");
115 // The returned value is always >= 0, a valid itable index.
116 return _call_index;
117 }
118
119 // debugging
120 #ifdef ASSERT
121 bool has_vtable_index() const { return _call_index >= 0 && _call_kind != CallInfo::itable_call; }
122 bool is_statically_bound() const { return _call_index == Method::nonvirtual_vtable_index; }
123 #endif //ASSERT
124 void verify() PRODUCT_RETURN;
125 void print() PRODUCT_RETURN;
126 };
127
128
129 // Condensed information from constant pool to use to resolve the method or field.
130 // resolved_klass = specified class (i.e., static receiver class)
131 // current_klass = sending method holder (i.e., class containing the method
132 // containing the call being resolved)
133 // current_method = sending method (relevant for field resolution)
134 class LinkInfo : public StackObj {
135 Symbol* _name; // extracted from JVM_CONSTANT_NameAndType
136 Symbol* _signature;
137 Klass* _resolved_klass; // class that the constant pool entry points to
138 Klass* _current_klass; // class that owns the constant pool
139 methodHandle _current_method; // sending method
140 bool _check_access;
141 bool _check_loader_constraints;
142 constantTag _tag;
143
144 public:
145 enum class AccessCheck { required, skip };
146 enum class LoaderConstraintCheck { required, skip };
147
148 LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, Bytecodes::Code code, TRAPS);
149 LinkInfo(const constantPoolHandle& pool, int index, Bytecodes::Code code, TRAPS);
150
151 // Condensed information from other call sites within the vm.
152 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, Klass* current_klass,
153 AccessCheck check_access = AccessCheck::required,
154 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required,
155 constantTag tag = JVM_CONSTANT_Invalid) :
156 _name(name),
157 _signature(signature),
158 _resolved_klass(resolved_klass),
159 _current_klass(current_klass),
160 _current_method(methodHandle()),
161 _check_access(check_access == AccessCheck::required),
162 _check_loader_constraints(check_loader_constraints == LoaderConstraintCheck::required),
163 _tag(tag) {
164 assert(_resolved_klass != nullptr, "must always have a resolved_klass");
165 }
166
167 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, const methodHandle& current_method,
168 AccessCheck check_access = AccessCheck::required,
169 LoaderConstraintCheck check_loader_constraints = LoaderConstraintCheck::required,
170 constantTag tag = JVM_CONSTANT_Invalid) :
171 LinkInfo(resolved_klass, name, signature, current_method->method_holder(), check_access, check_loader_constraints, tag) {
172 _current_method = current_method;
173 }
174
175 // Case where we just find the method and don't check access against the current class, used by JavaCalls
176 LinkInfo(Klass* resolved_klass, Symbol*name, Symbol* signature) :
177 LinkInfo(resolved_klass, name, signature, nullptr, AccessCheck::skip, LoaderConstraintCheck::skip,
178 JVM_CONSTANT_Invalid) {}
179
180 // accessors
181 Symbol* name() const { return _name; }
182 Symbol* signature() const { return _signature; }
183 Klass* resolved_klass() const { return _resolved_klass; }
184 Klass* current_klass() const { return _current_klass; }
185 Method* current_method() const { return _current_method(); }
186 constantTag tag() const { return _tag; }
187 bool check_access() const { return _check_access; }
188 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,
245 bool is_abstract_interpretation, 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,
252 bool is_abstract_interpretation, TRAPS);
253
254 static bool resolve_previously_linked_invokehandle(CallInfo& result,
255 const LinkInfo& link_info,
256 const constantPoolHandle& pool,
257 int index, TRAPS);
258
259 static void check_field_accessability(Klass* ref_klass,
260 Klass* resolved_klass,
261 Klass* sel_klass,
262 const fieldDescriptor& fd, TRAPS);
263 static void check_method_accessability(Klass* ref_klass,
264 Klass* resolved_klass,
265 Klass* sel_klass,
266 const methodHandle& sel_method, TRAPS);
267
268 // runtime resolving from constant pool
269 static void resolve_invokestatic (CallInfo& result,
270 const constantPoolHandle& pool, int index, TRAPS);
271 static void resolve_invokespecial (CallInfo& result, Handle recv,
272 const constantPoolHandle& pool, int index, TRAPS);
273 static void resolve_invokevirtual (CallInfo& result, Handle recv,
274 const constantPoolHandle& pool, int index, TRAPS);
275 static void resolve_invokeinterface(CallInfo& result, Handle recv,
276 const constantPoolHandle& pool, int index, TRAPS);
277 static void resolve_invokedynamic (CallInfo& result,
278 const constantPoolHandle& pool, int index, TRAPS);
279 static void resolve_invokehandle (CallInfo& result,
280 const constantPoolHandle& pool, int index, TRAPS);
281 public:
282 // constant pool resolving
283 static void check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS);
284
285 // static resolving calls (will not run any Java code);
286 // used only from Bytecode_invoke::static_target
287 static Method* resolve_method_statically(Bytecodes::Code code,
288 const constantPoolHandle& pool,
289 int index, TRAPS);
290
291 static void resolve_continuation_enter(CallInfo& callinfo, TRAPS);
292
293 static void resolve_field_access(fieldDescriptor& result,
294 const constantPoolHandle& pool,
295 int index,
296 const methodHandle& method,
297 Bytecodes::Code byte,
298 bool initialize_class, TRAPS);
299 static void resolve_field_access(fieldDescriptor& result,
300 const constantPoolHandle& pool,
301 int index,
302 const methodHandle& method,
303 Bytecodes::Code byte, TRAPS) {
304 resolve_field_access(result, pool, index, method, byte,
305 /* initialize_class*/true, THREAD);
306 }
307 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info,
308 Bytecodes::Code access_kind,
309 bool initialize_class, TRAPS);
310
311 static void resolve_static_call (CallInfo& result,
312 const LinkInfo& link_info,
313 bool initialize_klass, TRAPS);
314 static void resolve_special_call (CallInfo& result,
315 Handle recv,
316 const LinkInfo& link_info,
317 TRAPS);
318 static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass,
319 const LinkInfo& link_info,
320 bool check_null_and_abstract, TRAPS);
321 static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass,
322 const LinkInfo& link_info,
323 bool check_null_and_abstract, TRAPS);
324 static void resolve_handle_call (CallInfo& result,
325 const LinkInfo& link_info, TRAPS);
326 static void resolve_dynamic_call (CallInfo& result,
327 BootstrapInfo& bootstrap_specifier, TRAPS);
328
329 static void cds_resolve_virtual_call (CallInfo& result, const LinkInfo& link_info, TRAPS);
330 static void cds_resolve_interface_call(CallInfo& result, const LinkInfo& link_info, TRAPS);
331 static void cds_resolve_special_call (CallInfo& result, const LinkInfo& link_info, TRAPS);
332
333 // same as above for compile-time resolution; but returns null handle instead of throwing
334 // an exception on error also, does not initialize klass (i.e., no side effects)
335 static Method* resolve_virtual_call_or_null(Klass* receiver_klass,
336 const LinkInfo& link_info);
337 static Method* resolve_interface_call_or_null(Klass* receiver_klass,
338 const LinkInfo& link_info);
339 static Method* resolve_static_call_or_null(const LinkInfo& link_info);
340 static Method* resolve_special_call_or_null(const LinkInfo& link_info);
341
342 static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method);
343
344 // same as above for compile-time resolution; returns vtable_index if current_klass if linked
345 static int resolve_virtual_vtable_index (Klass* receiver_klass,
346 const LinkInfo& link_info);
347
348 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful)
349 static Method* linktime_resolve_virtual_method_or_null (const LinkInfo& link_info);
350 static Method* linktime_resolve_interface_method_or_null(const LinkInfo& link_info);
351
352 // runtime resolving from constant pool
353 static void resolve_invoke(CallInfo& result, Handle recv,
354 const constantPoolHandle& pool, int index,
355 Bytecodes::Code byte, TRAPS);
356
357 // runtime resolving from attached method
358 static void resolve_invoke(CallInfo& result, Handle& recv,
359 const methodHandle& attached_method,
360 Bytecodes::Code byte, bool check_null_and_abstract, TRAPS);
361
362 // Only resolved method known.
363 static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) {
364 throw_abstract_method_error(resolved_method, methodHandle(), nullptr, CHECK);
365 }
366 // Resolved method and receiver klass know.
367 static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) {
368 throw_abstract_method_error(resolved_method, methodHandle(), recv_klass, CHECK);
369 }
370 // Selected method is abstract.
371 static void throw_abstract_method_error(const methodHandle& resolved_method,
372 const methodHandle& selected_method,
373 Klass *recv_klass, TRAPS);
374 };
375 #endif // SHARE_INTERPRETER_LINKRESOLVER_HPP