1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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 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