/* * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_INTERPRETER_LINKRESOLVER_HPP #define SHARE_VM_INTERPRETER_LINKRESOLVER_HPP #include "oops/method.hpp" // All the necessary definitions for run-time link resolution. // CallInfo provides all the information gathered for a particular // linked call site after resolving it. A link is any reference // made from within the bytecodes of a method to an object outside of // that method. If the info is invalid, the link has not been resolved // successfully. class CallInfo : public StackObj { public: // Ways that a method call might be selected (or not) based on receiver type. // Note that an invokevirtual instruction might be linked with no_dispatch, // and an invokeinterface instruction might be linked with any of the three options enum CallKind { direct_call, // jump into resolved_method (must be concrete) vtable_call, // select recv.klass.method_at_vtable(index) itable_call, // select recv.klass.method_at_itable(resolved_method.holder, index) unknown_kind = -1 }; private: Klass* _resolved_klass; // static receiver klass, resolved from a symbolic reference Klass* _selected_klass; // dynamic receiver class (same as static, or subklass) methodHandle _resolved_method; // static target method methodHandle _selected_method; // dynamic (actual) target method CallKind _call_kind; // kind of call (static(=bytecode static/special + // others inferred), vtable, itable) int _call_index; // vtable or itable index of selected class method (if any) Handle _resolved_appendix; // extra argument in constant pool (if CPCE::has_appendix) Handle _resolved_method_type; // MethodType (for invokedynamic and invokehandle call sites) Handle _resolved_method_name; // Object holding the ResolvedMethodName void set_static(Klass* resolved_klass, const methodHandle& resolved_method, TRAPS); void set_interface(Klass* resolved_klass, Klass* selected_klass, const methodHandle& resolved_method, const methodHandle& selected_method, int itable_index, TRAPS); void set_virtual(Klass* resolved_klass, Klass* selected_klass, const methodHandle& resolved_method, const methodHandle& selected_method, int vtable_index, TRAPS); void set_handle(const methodHandle& resolved_method, Handle resolved_appendix, Handle resolved_method_type, TRAPS); void set_handle(Klass* resolved_klass, const methodHandle& resolved_method, Handle resolved_appendix, Handle resolved_method_type, TRAPS); void set_common(Klass* resolved_klass, Klass* selected_klass, const methodHandle& resolved_method, const methodHandle& selected_method, CallKind kind, int index, TRAPS); friend class LinkResolver; public: CallInfo() { #ifndef PRODUCT _call_kind = CallInfo::unknown_kind; _call_index = Method::garbage_vtable_index; #endif //PRODUCT } // utility to extract an effective CallInfo from a method and an optional receiver limit // does not queue the method for compilation. This also creates a ResolvedMethodName // object for the resolved_method. CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS); Klass* resolved_klass() const { return _resolved_klass; } Klass* selected_klass() const { return _selected_klass; } methodHandle resolved_method() const { return _resolved_method; } methodHandle selected_method() const { return _selected_method; } Handle resolved_appendix() const { return _resolved_appendix; } Handle resolved_method_type() const { return _resolved_method_type; } Handle resolved_method_name() const { return _resolved_method_name; } // Materialize a java.lang.invoke.ResolvedMethodName for this resolved_method void set_resolved_method_name(TRAPS); BasicType result_type() const { return selected_method()->result_type(); } CallKind call_kind() const { return _call_kind; } int call_index() const { return _call_index; } int vtable_index() const { // Even for interface calls the vtable index could be non-negative. // See CallInfo::set_interface. assert(has_vtable_index() || is_statically_bound(), ""); assert(call_kind() == vtable_call || call_kind() == direct_call, ""); // The returned value is < 0 if the call is statically bound. // But, the returned value may be >= 0 even if the kind is direct_call. // It is up to the caller to decide which way to go. return _call_index; } int itable_index() const { assert(call_kind() == itable_call, ""); // The returned value is always >= 0, a valid itable index. return _call_index; } // debugging #ifdef ASSERT bool has_vtable_index() const { return _call_index >= 0 && _call_kind != CallInfo::itable_call; } bool is_statically_bound() const { return _call_index == Method::nonvirtual_vtable_index; } #endif //ASSERT void verify() PRODUCT_RETURN; void print() PRODUCT_RETURN; }; // Condensed information from constant pool to use to resolve the method or field. // resolved_klass = specified class (i.e., static receiver class) // current_klass = sending method holder (i.e., class containing the method // containing the call being resolved) // current_method = sending method (relevant for field resolution) class LinkInfo : public StackObj { Symbol* _name; // extracted from JVM_CONSTANT_NameAndType Symbol* _signature; Klass* _resolved_klass; // class that the constant pool entry points to Klass* _current_klass; // class that owns the constant pool methodHandle _current_method; // sending method bool _check_access; constantTag _tag; public: enum AccessCheck { needs_access_check, skip_access_check }; LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, TRAPS); LinkInfo(const constantPoolHandle& pool, int index, TRAPS); // Condensed information from other call sites within the vm. LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, Klass* current_klass, AccessCheck check_access = needs_access_check, constantTag tag = JVM_CONSTANT_Invalid) : _resolved_klass(resolved_klass), _name(name), _signature(signature), _current_klass(current_klass), _current_method(methodHandle()), _check_access(check_access == needs_access_check), _tag(tag) {} LinkInfo(Klass* resolved_klass, Symbol* name, Symbol* signature, const methodHandle& current_method, AccessCheck check_access = needs_access_check, constantTag tag = JVM_CONSTANT_Invalid) : _resolved_klass(resolved_klass), _name(name), _signature(signature), _current_klass(current_method->method_holder()), _current_method(current_method), _check_access(check_access == needs_access_check), _tag(tag) {} // Case where we just find the method and don't check access against the current class LinkInfo(Klass* resolved_klass, Symbol*name, Symbol* signature) : _resolved_klass(resolved_klass), _name(name), _signature(signature), _current_klass(NULL), _current_method(methodHandle()), _check_access(false), _tag(JVM_CONSTANT_Invalid) {} // accessors Symbol* name() const { return _name; } Symbol* signature() const { return _signature; } Klass* resolved_klass() const { return _resolved_klass; } Klass* current_klass() const { return _current_klass; } methodHandle current_method() const { return _current_method; } constantTag tag() const { return _tag; } bool check_access() const { return _check_access; } char* method_string() const; void print() PRODUCT_RETURN; }; // Link information for getfield/putfield & getstatic/putstatic bytecodes // is represented using a fieldDescriptor. // The LinkResolver is used to resolve constant-pool references at run-time. // It does all necessary link-time checks & throws exceptions if necessary. class LinkResolver: AllStatic { friend class klassVtable; friend class klassItable; private: static Method* lookup_method_in_klasses(const LinkInfo& link_info, bool checkpolymorphism, bool in_imethod_resolve); static Method* lookup_method_in_interfaces(const LinkInfo& link_info); static methodHandle lookup_polymorphic_method(const LinkInfo& link_info, Handle *appendix_result_or_null, Handle *method_type_result, TRAPS); JVMCI_ONLY(public:) // Needed for CompilerToVM.resolveMethod() // Not Linktime so doesn't take LinkInfo static methodHandle lookup_instance_method_in_klasses ( Klass* klass, Symbol* name, Symbol* signature, TRAPS); JVMCI_ONLY(private:) // Similar loader constraint checking functions that throw // LinkageError with descriptive message. static void check_method_loader_constraints(const LinkInfo& link_info, const methodHandle& resolved_method, const char* method_type, TRAPS); static void check_field_loader_constraints(Symbol* field, Symbol* sig, Klass* current_klass, Klass* sel_klass, TRAPS); static methodHandle resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS); static methodHandle resolve_method (const LinkInfo& link_info, Bytecodes::Code code, TRAPS); static methodHandle linktime_resolve_static_method (const LinkInfo& link_info, TRAPS); static methodHandle linktime_resolve_special_method (const LinkInfo& link_info, TRAPS); static methodHandle linktime_resolve_virtual_method (const LinkInfo& link_info, TRAPS); static methodHandle linktime_resolve_interface_method (const LinkInfo& link_info, TRAPS); static void runtime_resolve_special_method (CallInfo& result, const LinkInfo& link_info, const methodHandle& resolved_method, Handle recv, TRAPS); static void runtime_resolve_virtual_method (CallInfo& result, const methodHandle& resolved_method, Klass* resolved_klass, Handle recv, Klass* recv_klass, bool check_null_and_abstract, TRAPS); static void runtime_resolve_interface_method (CallInfo& result, const methodHandle& resolved_method, Klass* resolved_klass, Handle recv, Klass* recv_klass, bool check_null_and_abstract, TRAPS); static void check_field_accessability(Klass* ref_klass, Klass* resolved_klass, Klass* sel_klass, const fieldDescriptor& fd, TRAPS); static void check_method_accessability(Klass* ref_klass, Klass* resolved_klass, Klass* sel_klass, const methodHandle& sel_method, TRAPS); // runtime resolving from constant pool static void resolve_invokestatic (CallInfo& result, const constantPoolHandle& pool, int index, TRAPS); static void resolve_invokespecial (CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, TRAPS); static void resolve_invokevirtual (CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, TRAPS); static void resolve_invokeinterface(CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, TRAPS); static void resolve_invokedynamic (CallInfo& result, const constantPoolHandle& pool, int index, TRAPS); static void resolve_invokehandle (CallInfo& result, const constantPoolHandle& pool, int index, TRAPS); public: // constant pool resolving static void check_klass_accessability(Klass* ref_klass, Klass* sel_klass, bool fold_type_to_class, TRAPS); // The optional 'fold_type_to_class' means that a derived type (array) // is first converted to the class it is derived from (element type). // If this element type is not a class, then the check passes quietly. // This is usually what is needed, but a few existing uses might break // if this flag were always turned on. FIXME: See if it can be, always. static void check_klass_accessability(Klass* ref_klass, Klass* sel_klass, TRAPS) { return check_klass_accessability(ref_klass, sel_klass, false, THREAD); } // static resolving calls (will not run any Java code); // used only from Bytecode_invoke::static_target static methodHandle resolve_method_statically(Bytecodes::Code code, const constantPoolHandle& pool, int index, TRAPS); static void resolve_field_access(fieldDescriptor& result, const constantPoolHandle& pool, int index, const methodHandle& method, Bytecodes::Code byte, TRAPS); static void resolve_field(fieldDescriptor& result, const LinkInfo& link_info, Bytecodes::Code access_kind, bool initialize_class, TRAPS); static void resolve_static_call (CallInfo& result, const LinkInfo& link_info, bool initialize_klass, TRAPS); static void resolve_special_call (CallInfo& result, Handle recv, const LinkInfo& link_info, TRAPS); static void resolve_virtual_call (CallInfo& result, Handle recv, Klass* recv_klass, const LinkInfo& link_info, bool check_null_and_abstract, TRAPS); static void resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass, const LinkInfo& link_info, bool check_null_and_abstract, TRAPS); static void resolve_handle_call (CallInfo& result, const LinkInfo& link_info, TRAPS); static void resolve_dynamic_call (CallInfo& result, int pool_index, Handle bootstrap_specifier, Symbol* method_name, Symbol* method_signature, Klass* current_klass, TRAPS); // same as above for compile-time resolution; but returns null handle instead of throwing // an exception on error also, does not initialize klass (i.e., no side effects) static methodHandle resolve_virtual_call_or_null (Klass* receiver_klass, const LinkInfo& link_info); static methodHandle resolve_interface_call_or_null(Klass* receiver_klass, const LinkInfo& link_info); static methodHandle resolve_static_call_or_null (const LinkInfo& link_info); static methodHandle resolve_special_call_or_null (const LinkInfo& link_info); static int vtable_index_of_interface_method(Klass* klass, const methodHandle& resolved_method); // same as above for compile-time resolution; returns vtable_index if current_klass if linked static int resolve_virtual_vtable_index (Klass* receiver_klass, const LinkInfo& link_info); // static resolving for compiler (does not throw exceptions, returns null handle if unsuccessful) static methodHandle linktime_resolve_virtual_method_or_null (const LinkInfo& link_info); static methodHandle linktime_resolve_interface_method_or_null(const LinkInfo& link_info); // runtime resolving from constant pool static void resolve_invoke(CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, Bytecodes::Code byte, TRAPS); // runtime resolving from attached method static void resolve_invoke(CallInfo& result, Handle& recv, const methodHandle& attached_method, Bytecodes::Code byte, TRAPS); public: // Only resolved method known. static void throw_abstract_method_error(const methodHandle& resolved_method, TRAPS) { throw_abstract_method_error(resolved_method, NULL, NULL, CHECK); } // Resolved method and receiver klass know. static void throw_abstract_method_error(const methodHandle& resolved_method, Klass *recv_klass, TRAPS) { throw_abstract_method_error(resolved_method, NULL, recv_klass, CHECK); } // Selected method is abstract. static void throw_abstract_method_error(const methodHandle& resolved_method, const methodHandle& selected_method, Klass *recv_klass, TRAPS); }; #endif // SHARE_VM_INTERPRETER_LINKRESOLVER_HPP