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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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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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 Klass* _selected_klass; // dynamic receiver class (same as static, or subklass)
53 methodHandle _resolved_method; // static target method
54 methodHandle _selected_method; // dynamic (actual) target method
55 CallKind _call_kind; // kind of call (static(=bytecode static/special +
56 // others inferred), vtable, itable)
57 int _call_index; // vtable or itable index of selected class method (if any)
58 Handle _resolved_appendix; // extra argument in constant pool (if CPCE::has_appendix)
59 Handle _resolved_method_name; // Object holding the ResolvedMethodName
60
61 void set_static(Klass* resolved_klass, const methodHandle& resolved_method, TRAPS);
62 void set_interface(Klass* resolved_klass, Klass* selected_klass,
63 const methodHandle& resolved_method,
64 const methodHandle& selected_method,
65 int itable_index, TRAPS);
66 void set_virtual(Klass* resolved_klass, Klass* selected_klass,
67 const methodHandle& resolved_method,
68 const methodHandle& selected_method,
69 int vtable_index, TRAPS);
70 void set_handle(const methodHandle& resolved_method,
71 Handle resolved_appendix, TRAPS);
72 void set_handle(Klass* resolved_klass,
73 const methodHandle& resolved_method,
74 Handle resolved_appendix, TRAPS);
75 void set_common(Klass* resolved_klass, Klass* selected_klass,
76 const methodHandle& resolved_method,
77 const methodHandle& selected_method,
78 CallKind kind,
79 int index, TRAPS);
80
81 friend class BootstrapInfo;
82 friend class LinkResolver;
83
84 public:
85 CallInfo() {
86 #ifndef PRODUCT
87 _call_kind = CallInfo::unknown_kind;
88 _call_index = Method::garbage_vtable_index;
89 #endif //PRODUCT
90 }
91
92 // utility to extract an effective CallInfo from a method and an optional receiver limit
93 // does not queue the method for compilation. This also creates a ResolvedMethodName
94 // object for the resolved_method.
95 CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS);
96
97 Klass* resolved_klass() const { return _resolved_klass; }
98 Klass* selected_klass() const { return _selected_klass; }
99 methodHandle resolved_method() const { return _resolved_method; }
100 methodHandle selected_method() const { return _selected_method; }
101 Handle resolved_appendix() const { return _resolved_appendix; }
102 Handle resolved_method_name() const { return _resolved_method_name; }
103 // Materialize a java.lang.invoke.ResolvedMethodName for this resolved_method
104 void set_resolved_method_name(TRAPS);
105
106 BasicType result_type() const { return selected_method()->result_type(); }
107 CallKind call_kind() const { return _call_kind; }
108 int call_index() const { return _call_index; }
109 int vtable_index() const {
110 // Even for interface calls the vtable index could be non-negative.
111 // See CallInfo::set_interface.
112 assert(has_vtable_index() || is_statically_bound(), "");
113 assert(call_kind() == vtable_call || call_kind() == direct_call, "");
114 // The returned value is < 0 if the call is statically bound.
115 // But, the returned value may be >= 0 even if the kind is direct_call.
116 // It is up to the caller to decide which way to go.
117 return _call_index;
118 }
119 int itable_index() const {
120 assert(call_kind() == itable_call, "");
121 // The returned value is always >= 0, a valid itable index.
122 return _call_index;
123 }
124
125 // debugging
126 #ifdef ASSERT
127 bool has_vtable_index() const { return _call_index >= 0 && _call_kind != CallInfo::itable_call; }
128 bool is_statically_bound() const { return _call_index == Method::nonvirtual_vtable_index; }
129 #endif //ASSERT
130 void verify() PRODUCT_RETURN;
131 void print() PRODUCT_RETURN;
132 };
133
134
135 // Condensed information from constant pool to use to resolve the method or field.
136 // resolved_klass = specified class (i.e., static receiver class)
137 // current_klass = sending method holder (i.e., class containing the method
138 // containing the call being resolved)
139 // current_method = sending method (relevant for field resolution)
140 class LinkInfo : public StackObj {
141 Symbol* _name; // extracted from JVM_CONSTANT_NameAndType
142 Symbol* _signature;
143 Klass* _resolved_klass; // class that the constant pool entry points to
144 Klass* _current_klass; // class that owns the constant pool
145 methodHandle _current_method; // sending method
146 bool _check_access;
147 constantTag _tag;
148
149 public:
150 enum AccessCheck {
151 needs_access_check,
152 skip_access_check
153 };
154
155 LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, TRAPS);
156 LinkInfo(const constantPoolHandle& pool, int index, TRAPS);
157
158 // Condensed information from other call sites within the vm.
159 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, Klass* current_klass,
160 AccessCheck check_access = needs_access_check,
161 constantTag tag = JVM_CONSTANT_Invalid) :
162 _name(name),
163 _signature(signature), _resolved_klass(resolved_klass), _current_klass(current_klass), _current_method(methodHandle()),
164 _check_access(check_access == needs_access_check), _tag(tag) {}
165
166 LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, const methodHandle& current_method,
167 AccessCheck check_access = needs_access_check,
168 constantTag tag = JVM_CONSTANT_Invalid) :
169 _name(name),
170 _signature(signature), _resolved_klass(resolved_klass), _current_klass(current_method->method_holder()), _current_method(current_method),
171 _check_access(check_access == needs_access_check), _tag(tag) {}
172
173 // Case where we just find the method and don't check access against the current class
174 LinkInfo(Klass* resolved_klass, Symbol*name, Symbol* signature) :
175 _name(name),
176 _signature(signature), _resolved_klass(resolved_klass), _current_klass(NULL), _current_method(methodHandle()),
177 _check_access(false), _tag(JVM_CONSTANT_Invalid) {}
178
179 // accessors
180 Symbol* name() const { return _name; }
181 Symbol* signature() const { return _signature; }
182 Klass* resolved_klass() const { return _resolved_klass; }
183 Klass* current_klass() const { return _current_klass; }
184 methodHandle current_method() const { return _current_method; }
185 constantTag tag() const { return _tag; }
186 bool check_access() const { return _check_access; }
187
188 void print() PRODUCT_RETURN;
189 };
190
191 // Link information for getfield/putfield & getstatic/putstatic bytecodes
192 // is represented using a fieldDescriptor.
193
194 // The LinkResolver is used to resolve constant-pool references at run-time.
195 // It does all necessary link-time checks & throws exceptions if necessary.
196
197 class LinkResolver: AllStatic {
198 friend class klassVtable;
199 friend class klassItable;
200
201 private:
202
203 static Method* lookup_method_in_klasses(const LinkInfo& link_info,
204 bool checkpolymorphism,
205 bool in_imethod_resolve);
206 static Method* lookup_method_in_interfaces(const LinkInfo& link_info);
207
208 static methodHandle lookup_polymorphic_method(const LinkInfo& link_info,
209 Handle *appendix_result_or_null, TRAPS);
210 JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod()
211 // Not Linktime so doesn't take LinkInfo
212 static methodHandle lookup_instance_method_in_klasses (Klass* klass, Symbol* name, Symbol* signature,
213 Klass::PrivateLookupMode private_mode, TRAPS);
214 JVMCI_ONLY(private:)
215
216 // Similar loader constraint checking functions that throw
217 // LinkageError with descriptive message.
218 static void check_method_loader_constraints(const LinkInfo& link_info,
219 const methodHandle& resolved_method,
220 const char* method_type, TRAPS);
221 static void check_field_loader_constraints(Symbol* field, Symbol* sig,
222 Klass* current_klass,
223 Klass* sel_klass, TRAPS);
224
225 static methodHandle resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS);
226 static methodHandle resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS);
227
228 static methodHandle linktime_resolve_static_method (const LinkInfo& link_info, TRAPS);
229 static methodHandle linktime_resolve_special_method (const LinkInfo& link_info, TRAPS);
230 static methodHandle linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS);
231 static methodHandle linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS);
232
233 static void runtime_resolve_special_method (CallInfo& result,
234 const LinkInfo& link_info,
235 const methodHandle& resolved_method,
236 Handle recv, TRAPS);
237
238 static void runtime_resolve_virtual_method (CallInfo& result,
239 const methodHandle& resolved_method,
240 Klass* resolved_klass,
241 Handle recv,
242 Klass* recv_klass,
243 bool check_null_and_abstract, TRAPS);
244 static void runtime_resolve_interface_method (CallInfo& result,
245 const methodHandle& resolved_method,
246 Klass* resolved_klass,
247 Handle recv,
248 Klass* recv_klass,
249 bool check_null_and_abstract, TRAPS);
250
251 static void check_field_accessability(Klass* ref_klass,
252 Klass* resolved_klass,
253 Klass* sel_klass,
254 const fieldDescriptor& fd, TRAPS);
255 static void check_method_accessability(Klass* ref_klass,
256 Klass* resolved_klass,
257 Klass* sel_klass,
258 const methodHandle& sel_method, TRAPS);
259
260 // runtime resolving from constant pool
261 static void resolve_invokestatic (CallInfo& result,
262 const constantPoolHandle& pool, int index, TRAPS);
263 static void resolve_invokespecial (CallInfo& result, Handle recv,
264 const constantPoolHandle& pool, int index, TRAPS);
265 static void resolve_invokevirtual (CallInfo& result, Handle recv,
266 const constantPoolHandle& pool, int index, TRAPS);
267 static void resolve_invokeinterface(CallInfo& result, Handle recv,
268 const constantPoolHandle& pool, int index, TRAPS);
269 static void resolve_invokedynamic (CallInfo& result,
270 const constantPoolHandle& pool, int index, TRAPS);
271 static void resolve_invokehandle (CallInfo& result,
272 const constantPoolHandle& pool, int index, TRAPS);
273 public:
274 // constant pool resolving
275 static void check_klass_accessability(Klass* ref_klass, Klass* sel_klass,
276 bool fold_type_to_class, TRAPS);
277 // The optional 'fold_type_to_class' means that a derived type (array)
278 // is first converted to the class it is derived from (element type).
279 // If this element type is not a class, then the check passes quietly.
280 // This is usually what is needed, but a few existing uses might break
281 // if this flag were always turned on. FIXME: See if it can be, always.
282 static void check_klass_accessability(Klass* ref_klass, Klass* sel_klass, TRAPS) {
283 return check_klass_accessability(ref_klass, sel_klass, false, THREAD);
284 }
285
286 // static resolving calls (will not run any Java code);
287 // used only from Bytecode_invoke::static_target
288 static methodHandle resolve_method_statically(Bytecodes::Code code,
289 const constantPoolHandle& pool,
290 int index, 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, TRAPS);
297 static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info,
298 Bytecodes::Code access_kind,
299 bool initialize_class, TRAPS);
300
301 static void resolve_static_call (CallInfo& result,
302 const LinkInfo& link_info,
303 bool initialize_klass, TRAPS);
304 static void resolve_special_call (CallInfo& result,
305 Handle recv,
306 const LinkInfo& link_info,
307 TRAPS);
308 static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass,
309 const LinkInfo& link_info,
310 bool check_null_and_abstract, TRAPS);
311 static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass,
312 const LinkInfo& link_info,
313 bool check_null_and_abstract, TRAPS);
314 static void resolve_handle_call (CallInfo& result,
315 const LinkInfo& link_info, TRAPS);
316 static void resolve_dynamic_call (CallInfo& result,
317 BootstrapInfo& bootstrap_specifier, TRAPS);
318
319 // same as above for compile-time resolution; but returns null handle instead of throwing
320 // an exception on error also, does not initialize klass (i.e., no side effects)
321 static methodHandle resolve_virtual_call_or_null (Klass* receiver_klass,
322 const LinkInfo& link_info);
323 static methodHandle resolve_interface_call_or_null(Klass* receiver_klass,
324 const LinkInfo& link_info);
325 static methodHandle resolve_static_call_or_null (const LinkInfo& link_info);
326 static methodHandle resolve_special_call_or_null (const LinkInfo& link_info);
327
328 static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method);
329
330 // same as above for compile-time resolution; returns vtable_index if current_klass if linked
331 static int resolve_virtual_vtable_index (Klass* receiver_klass,
332 const LinkInfo& link_info);
333
334 // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful)
335 static methodHandle linktime_resolve_virtual_method_or_null (const LinkInfo& link_info);
336 static methodHandle linktime_resolve_interface_method_or_null(const LinkInfo& link_info);
337
338 // runtime resolving from constant pool
339 static void resolve_invoke(CallInfo& result, Handle recv,
340 const constantPoolHandle& pool, int index,
341 Bytecodes::Code byte, TRAPS);
342
343 // runtime resolving from attached method
344 static void resolve_invoke(CallInfo& result, Handle& recv,
345 const methodHandle& attached_method,
346 Bytecodes::Code byte, TRAPS);
347
348 public:
349 // Only resolved method known.
350 static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) {
351 throw_abstract_method_error(resolved_method, NULL, NULL, CHECK);
352 }
353 // Resolved method and receiver klass know.
354 static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) {
355 throw_abstract_method_error(resolved_method, NULL, recv_klass, CHECK);
356 }
357 // Selected method is abstract.
358 static void throw_abstract_method_error(const methodHandle& resolved_method,
359 const methodHandle& selected_method,
360 Klass *recv_klass, TRAPS);
361 };
362 #endif // SHARE_INTERPRETER_LINKRESOLVER_HPP