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 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 enum class StaticMode : uint8_t {
193 dont_initialize_klass,
194 initialize_klass,
195 initialize_klass_preemptable
196 };
197
198 // Link information for getfield/putfield & getstatic/putstatic bytecodes
199 // is represented using a fieldDescriptor.
200
201 // The LinkResolver is used to resolve constant-pool references at run-time.
202 // It does all necessary link-time checks & throws exceptions if necessary.
203
204 class LinkResolver: AllStatic {
205 friend class klassVtable;
206 friend class klassItable;
207
208 private:
209
210 static Method* lookup_method_in_klasses(const LinkInfo& link_info,
211 bool checkpolymorphism,
212 bool in_imethod_resolve);
213 static Method* lookup_method_in_interfaces(const LinkInfo& link_info);
214
215 static Method* lookup_polymorphic_method(const LinkInfo& link_info,
216 Handle *appendix_result_or_null, TRAPS);
217 JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod()
218 // Not Linktime so doesn't take LinkInfo
219 static Method* lookup_instance_method_in_klasses (Klass* klass, Symbol* name, Symbol* signature,
220 Klass::PrivateLookupMode private_mode);
221 JVMCI_ONLY(private:)
222
223 // Similar loader constraint checking functions that throw
224 // LinkageError with descriptive message.
225 static void check_method_loader_constraints(const LinkInfo& link_info,
226 const methodHandle& resolved_method,
227 const char* method_type, TRAPS);
228 static void check_field_loader_constraints(Symbol* field, Symbol* sig,
229 Klass* current_klass,
230 Klass* sel_klass, TRAPS);
231
232 static Method* resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS);
233 static Method* resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS);
234
235 static Method* linktime_resolve_static_method (const LinkInfo& link_info, TRAPS);
236 static Method* linktime_resolve_special_method (const LinkInfo& link_info, TRAPS);
237 static Method* linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS);
238 static Method* linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS);
239
240 static void runtime_resolve_special_method (CallInfo& result,
241 const LinkInfo& link_info,
242 const methodHandle& resolved_method,
243 Handle recv, TRAPS);
244
245 static void runtime_resolve_virtual_method (CallInfo& result,
246 const methodHandle& resolved_method,
247 Klass* resolved_klass,
248 Handle recv,
249 Klass* recv_klass,
250 bool check_null_and_abstract,
251 bool is_abstract_interpretation, TRAPS);
252 static void runtime_resolve_interface_method (CallInfo& result,
253 const methodHandle& resolved_method,
254 Klass* resolved_klass,
255 Handle recv,
256 Klass* recv_klass,
257 bool check_null_and_abstract,
258 bool is_abstract_interpretation, TRAPS);
259
260 static bool resolve_previously_linked_invokehandle(CallInfo& result,
261 const LinkInfo& link_info,
262 const constantPoolHandle& pool,
263 int index, TRAPS);
264
265 static void check_field_accessability(Klass* ref_klass,
266 Klass* resolved_klass,
267 Klass* sel_klass,
268 const fieldDescriptor& fd, TRAPS);
269 static void check_method_accessability(Klass* ref_klass,
270 Klass* resolved_klass,
271 Klass* sel_klass,
272 const methodHandle& sel_method, TRAPS);
273
274 // runtime resolving from constant pool
275 static void resolve_invokestatic (CallInfo& result,
276 const constantPoolHandle& pool, int index, StaticMode mode, TRAPS);
277 static void resolve_invokespecial (CallInfo& result, Handle recv,
278 const constantPoolHandle& pool, int index, TRAPS);
279 static void resolve_invokevirtual (CallInfo& result, Handle recv,
280 const constantPoolHandle& pool, int index, TRAPS);
281 static void resolve_invokeinterface(CallInfo& result, Handle recv,
282 const constantPoolHandle& pool, int index, TRAPS);
283 static void resolve_invokedynamic (CallInfo& result,
284 const constantPoolHandle& pool, int index, TRAPS);
285 static void resolve_invokehandle (CallInfo& result,
286 const constantPoolHandle& pool, int index, TRAPS);
287 public:
288 // constant pool resolving
289 static void check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS);
290
291 // static resolving calls (will not run any Java code);
292 // used only from Bytecode_invoke::static_target
293 static Method* resolve_method_statically(Bytecodes::Code code,
294 const constantPoolHandle& pool,
295 int index, TRAPS);
296
297 static void resolve_continuation_enter(CallInfo& callinfo, TRAPS);
298
299 static void resolve_field_access(fieldDescriptor& result,
300 const constantPoolHandle& pool,
301 int index,
302 const methodHandle& method,
303 Bytecodes::Code byte,
304 StaticMode mode, TRAPS);
305 static void resolve_field_access(fieldDescriptor& result,
306 const constantPoolHandle& pool,
307 int index,
308 const methodHandle& method,
309 Bytecodes::Code byte, TRAPS) {
310 resolve_field_access(result, pool, index, method, byte,
311 StaticMode::initialize_klass, THREAD);
312 }
313 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info,
314 Bytecodes::Code access_kind,
315 StaticMode mode, TRAPS);
316
317 static void resolve_static_call (CallInfo& result,
318 const LinkInfo& link_info,
319 StaticMode mode, TRAPS);
320 static void resolve_special_call (CallInfo& result,
321 Handle recv,
322 const LinkInfo& link_info,
323 TRAPS);
324 static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass,
325 const LinkInfo& link_info,
326 bool check_null_and_abstract, TRAPS);
327 static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass,
328 const LinkInfo& link_info,
329 bool check_null_and_abstract, TRAPS);
330 static void resolve_handle_call (CallInfo& result,
331 const LinkInfo& link_info, TRAPS);
332 static void resolve_dynamic_call (CallInfo& result,
333 BootstrapInfo& bootstrap_specifier, TRAPS);
334
335 static void cds_resolve_virtual_call (CallInfo& result, const LinkInfo& link_info, TRAPS);
336 static void cds_resolve_interface_call(CallInfo& result, const LinkInfo& link_info, TRAPS);
337 static void cds_resolve_special_call (CallInfo& result, const LinkInfo& link_info, TRAPS);
338
339 // same as above for compile-time resolution; but returns null handle instead of throwing
340 // an exception on error also, does not initialize klass (i.e., no side effects)
341 static Method* resolve_virtual_call_or_null(Klass* receiver_klass,
342 const LinkInfo& link_info);
343 static Method* resolve_interface_call_or_null(Klass* receiver_klass,
344 const LinkInfo& link_info);
345 static Method* resolve_static_call_or_null(const LinkInfo& link_info);
346 static Method* resolve_special_call_or_null(const LinkInfo& link_info);
347
348 static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method);
349
350 // same as above for compile-time resolution; returns vtable_index if current_klass if linked
351 static int resolve_virtual_vtable_index (Klass* receiver_klass,
352 const LinkInfo& link_info);
353
354 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful)
355 static Method* linktime_resolve_virtual_method_or_null (const LinkInfo& link_info);
356 static Method* linktime_resolve_interface_method_or_null(const LinkInfo& link_info);
357
358 // runtime resolving from constant pool
359 static void resolve_invoke(CallInfo& result, Handle recv,
360 const constantPoolHandle& pool, int index,
361 Bytecodes::Code byte, StaticMode static_mode, TRAPS);
362 static void resolve_invoke(CallInfo& result, Handle recv,
363 const constantPoolHandle& pool, int index,
364 Bytecodes::Code byte, TRAPS) {
365 resolve_invoke(result, recv, pool, index, byte, StaticMode::initialize_klass, THREAD);
366 }
367
368 // runtime resolving from attached method
369 static void resolve_invoke(CallInfo& result, Handle& recv,
370 const methodHandle& attached_method,
371 Bytecodes::Code byte, TRAPS);
372
373 // Only resolved method known.
374 static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) {
375 throw_abstract_method_error(resolved_method, methodHandle(), nullptr, CHECK);
376 }
377 // Resolved method and receiver klass know.
378 static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) {
379 throw_abstract_method_error(resolved_method, methodHandle(), recv_klass, CHECK);
380 }
381 // Selected method is abstract.
382 static void throw_abstract_method_error(const methodHandle& resolved_method,
383 const methodHandle& selected_method,
384 Klass *recv_klass, TRAPS);
385 };
386 #endif // SHARE_INTERPRETER_LINKRESOLVER_HPP