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