diff -r faf2631b9334 -r 91b93f523ec6 src/share/vm/classfile/defaultMethods.cpp --- a/src/share/vm/classfile/defaultMethods.cpp Mon Aug 26 09:33:01 2013 +0200 +++ b/src/share/vm/classfile/defaultMethods.cpp Mon Aug 26 11:35:25 2013 -0400 @@ -25,7 +25,6 @@ #include "precompiled.hpp" #include "classfile/bytecodeAssembler.hpp" #include "classfile/defaultMethods.hpp" -#include "classfile/genericSignatures.hpp" #include "classfile/symbolTable.hpp" #include "memory/allocation.hpp" #include "memory/metadataFactory.hpp" @@ -75,14 +74,6 @@ } }; -class ContextMark : public PseudoScopeMark { - private: - generic::Context::Mark _mark; - public: - ContextMark(const generic::Context::Mark& cm) : _mark(cm) {} - virtual void destroy() { _mark.destroy(); } -}; - #ifndef PRODUCT static void print_slot(outputStream* str, Symbol* name, Symbol* signature) { ResourceMark rm; @@ -503,38 +494,6 @@ return SymbolTable::new_symbol(ss.base(), (int)ss.size(), CHECK_NULL); } -// A generic method family contains a set of all methods that implement a single -// language-level method. Because of erasure, these methods may have different -// signatures. As members of the set are collected while walking over the -// hierarchy, they are tagged with a qualification state. The qualification -// state for an erased method is set to disqualified if there exists a path -// from the root of hierarchy to the method that contains an interleaving -// language-equivalent method defined in an interface. -class GenericMethodFamily : public MethodFamily { - private: - - generic::MethodDescriptor* _descriptor; // language-level description - - public: - - GenericMethodFamily(generic::MethodDescriptor* canonical_desc) - : _descriptor(canonical_desc) {} - - generic::MethodDescriptor* descriptor() const { return _descriptor; } - - bool descriptor_matches(generic::MethodDescriptor* md, generic::Context* ctx) { - return descriptor()->covariant_match(md, ctx); - } - -#ifndef PRODUCT - Symbol* get_generic_sig() const { - - generic::Context ctx(NULL); // empty, as _descriptor already canonicalized - TempNewSymbol sig = descriptor()->reify_signature(&ctx, Thread::current()); - return sig; - } -#endif // ndef PRODUCT -}; class StateRestorer; @@ -571,26 +530,6 @@ StateRestorer* record_method_and_dq_further(Method* mo); }; - -// StatefulGenericMethodFamily is a wrapper around GenericMethodFamily that maintains the -// qualification state during hierarchy visitation, and applies that state -// when adding members to the GenericMethodFamily. -class StatefulGenericMethodFamily : public StatefulMethodFamily { - - public: - StatefulGenericMethodFamily(generic::MethodDescriptor* md, generic::Context* ctx) - : StatefulMethodFamily(new GenericMethodFamily(md->canonicalize(ctx))) { - - } - GenericMethodFamily* get_method_family() { - return (GenericMethodFamily*)_method_family; - } - - bool descriptor_matches(generic::MethodDescriptor* md, generic::Context* ctx) { - return get_method_family()->descriptor_matches(md, ctx); - } -}; - class StateRestorer : public PseudoScopeMark { private: StatefulMethodFamily* _method; @@ -616,39 +555,6 @@ return mark; } -class StatefulGenericMethodFamilies : public ResourceObj { - private: - GrowableArray _methods; - - public: - StatefulGenericMethodFamily* find_matching( - generic::MethodDescriptor* md, generic::Context* ctx) { - for (int i = 0; i < _methods.length(); ++i) { - StatefulGenericMethodFamily* existing = _methods.at(i); - if (existing->descriptor_matches(md, ctx)) { - return existing; - } - } - return NULL; - } - - StatefulGenericMethodFamily* find_matching_or_create( - generic::MethodDescriptor* md, generic::Context* ctx) { - StatefulGenericMethodFamily* method = find_matching(md, ctx); - if (method == NULL) { - method = new StatefulGenericMethodFamily(md, ctx); - _methods.append(method); - } - return method; - } - - void extract_families_into(GrowableArray* array) { - for (int i = 0; i < _methods.length(); ++i) { - array->append(_methods.at(i)->get_method_family()); - } - } -}; - // Represents a location corresponding to a vtable slot for methods that // neither the class nor any of it's ancestors provide an implementaion. // Default methods may be present to fill this slot. @@ -779,146 +685,11 @@ }; -// Iterates over the type hierarchy looking for all methods with a specific -// method name. The result of this is a set of method families each of -// which is populated with a set of methods that implement the same -// language-level signature. -class FindMethodsByGenericSig : public HierarchyVisitor { - private: - // Context data - Thread* THREAD; - generic::DescriptorCache* _cache; - Symbol* _method_name; - generic::Context* _ctx; - StatefulGenericMethodFamilies _families; - public: - - FindMethodsByGenericSig(generic::DescriptorCache* cache, Symbol* name, - generic::Context* ctx, Thread* thread) : - _cache(cache), _method_name(name), _ctx(ctx), THREAD(thread) {} - - void get_discovered_families(GrowableArray* methods) { - _families.extract_families_into(methods); - } - - void* new_node_data(InstanceKlass* cls) { return new PseudoScope(); } - void free_node_data(void* node_data) { - PseudoScope::cast(node_data)->destroy(); - } - - bool visit() { - PseudoScope* scope = PseudoScope::cast(current_data()); - InstanceKlass* klass = current_class(); - InstanceKlass* sub = current_depth() > 0 ? class_at_depth(1) : NULL; - - ContextMark* cm = new ContextMark(_ctx->mark()); - scope->add_mark(cm); // will restore context when scope is freed - - _ctx->apply_type_arguments(sub, klass, THREAD); - - int start, end = 0; - start = klass->find_method_by_name(_method_name, &end); - if (start != -1) { - for (int i = start; i < end; ++i) { - Method* m = klass->methods()->at(i); - // This gets the method's parameter list with its generic type - // parameters resolved - generic::MethodDescriptor* md = _cache->descriptor_for(m, THREAD); - - // Find all methods on this hierarchy that match this method - // (name, signature). This class collects other families of this - // method name. - StatefulGenericMethodFamily* family = - _families.find_matching_or_create(md, _ctx); - - if (klass->is_interface()) { - // ??? - StateRestorer* restorer = family->record_method_and_dq_further(m); - scope->add_mark(restorer); - } else { - // This is the rule that methods in classes "win" (bad word) over - // methods in interfaces. This works because of single inheritance - family->set_target_if_empty(m); - } - } - } - return true; - } -}; - -#ifndef PRODUCT -static void print_generic_families( - GrowableArray* methods, Symbol* match) { - streamIndentor si(tty, 4); - if (methods->length() == 0) { - tty->indent(); - tty->print_cr("No Logical Method found"); - } - for (int i = 0; i < methods->length(); ++i) { - tty->indent(); - GenericMethodFamily* lm = methods->at(i); - if (lm->contains_signature(match)) { - tty->print_cr(""); - } else { - tty->print_cr(""); - } - lm->print_sig_on(tty, lm->get_generic_sig(), 1); - } -} -#endif // ndef PRODUCT static void create_overpasses( GrowableArray* slots, InstanceKlass* klass, TRAPS); -static void generate_generic_defaults( - InstanceKlass* klass, GrowableArray* empty_slots, - EmptyVtableSlot* slot, int current_slot_index, TRAPS) { - - if (slot->is_bound()) { -#ifndef PRODUCT - if (TraceDefaultMethods) { - streamIndentor si(tty, 4); - tty->indent().print_cr("Already bound to logical method:"); - GenericMethodFamily* lm = (GenericMethodFamily*)(slot->get_binding()); - lm->print_sig_on(tty, lm->get_generic_sig(), 1); - } -#endif // ndef PRODUCT - return; // covered by previous processing - } - - generic::DescriptorCache cache; - - generic::Context ctx(&cache); - FindMethodsByGenericSig visitor(&cache, slot->name(), &ctx, CHECK); - visitor.run(klass); - - GrowableArray discovered_families; - visitor.get_discovered_families(&discovered_families); - -#ifndef PRODUCT - if (TraceDefaultMethods) { - print_generic_families(&discovered_families, slot->signature()); - } -#endif // ndef PRODUCT - - // Find and populate any other slots that match the discovered families - for (int j = current_slot_index; j < empty_slots->length(); ++j) { - EmptyVtableSlot* open_slot = empty_slots->at(j); - - if (slot->name() == open_slot->name()) { - for (int k = 0; k < discovered_families.length(); ++k) { - GenericMethodFamily* lm = discovered_families.at(k); - - if (lm->contains_signature(open_slot->signature())) { - lm->determine_target(klass, CHECK); - open_slot->bind_family(lm); - } - } - } - } -} - static void generate_erased_defaults( InstanceKlass* klass, GrowableArray* empty_slots, EmptyVtableSlot* slot, TRAPS) { @@ -943,21 +714,14 @@ // // First if finds any name/signature slots that need any implementation (either // because they are miranda or a superclass's implementation is an overpass -// itself). For each slot, iterate over the hierarchy, using generic signature -// information to partition any methods that match the name into method families -// where each family contains methods whose signatures are equivalent at the -// language level (i.e., their reified parameters match and return values are -// covariant). Check those sets to see if they contain a signature that matches -// the slot we're looking at (if we're lucky, there might be other empty slots -// that we can fill using the same analysis). +// itself). For each slot, iterate over the hierarchy, to see if they contain a +// signature that matches the slot we are looking at. // // For each slot filled, we generate an overpass method that either calls the // unique default method candidate using invokespecial, or throws an exception // (in the case of no default method candidates, or more than one valid -// candidate). These methods are then added to the class's method list. If -// the method set we're using contains methods (qualified or not) with a -// different runtime signature than the method we're creating, then we have to -// create bridges with those signatures too. +// candidate). These methods are then added to the class's method list. +// The JVM does not create bridges nor handle generic signatures here. void DefaultMethods::generate_default_methods( InstanceKlass* klass, GrowableArray* mirandas, TRAPS) { @@ -997,11 +761,7 @@ } #endif // ndef PRODUCT - if (ParseGenericDefaults) { - generate_generic_defaults(klass, empty_slots, slot, i, CHECK); - } else { - generate_erased_defaults(klass, empty_slots, slot, CHECK); - } + generate_erased_defaults(klass, empty_slots, slot, CHECK); } #ifndef PRODUCT if (TraceDefaultMethods) { @@ -1019,13 +779,13 @@ } /** - * Generic analysis was used upon interface '_target' and found a unique - * default method candidate with generic signature '_method_desc'. This + * Interface inheritance rules were used to find a unique default method + * candidate for the resolved class. This * method is only viable if it would also be in the set of default method * candidates if we ran a full analysis on the current class. * * The only reason that the method would not be in the set of candidates for - * the current class is if that there's another covariantly matching method + * the current class is if that there's another matching method * which is "more specific" than the found method -- i.e., one could find a * path in the interface hierarchy in which the matching method appears * before we get to '_target'. @@ -1110,48 +870,6 @@ : ShadowChecker(thread, name, holder, target) {} }; -class GenericShadowChecker : public ShadowChecker { - private: - generic::DescriptorCache* _cache; - generic::MethodDescriptor* _method_desc; - - bool path_has_shadow() { - generic::Context ctx(_cache); - - for (int i = current_depth() - 1; i > 0; --i) { - InstanceKlass* ik = class_at_depth(i); - InstanceKlass* sub = class_at_depth(i + 1); - ctx.apply_type_arguments(sub, ik, THREAD); - - if (ik->is_interface()) { - int end; - int start = ik->find_method_by_name(_method_name, &end); - if (start != -1) { - for (int j = start; j < end; ++j) { - Method* mo = ik->methods()->at(j); - generic::MethodDescriptor* md = _cache->descriptor_for(mo, THREAD); - if (_method_desc->covariant_match(md, &ctx)) { - return true; - } - } - } - } - } - return false; - } - - public: - - GenericShadowChecker(generic::DescriptorCache* cache, Thread* thread, - Symbol* name, InstanceKlass* holder, generic::MethodDescriptor* desc, - InstanceKlass* target) - : ShadowChecker(thread, name, holder, target) { - _cache = cache; - _method_desc = desc; - } -}; - - // Find the unique qualified candidate from the perspective of the super_class // which is the resolved_klass, which must be an immediate superinterface @@ -1203,66 +921,6 @@ } } -// super_class is assumed to be the direct super of current_class -Method* find_generic_super_default( InstanceKlass* current_class, - InstanceKlass* super_class, - Symbol* method_name, Symbol* sig, TRAPS) { - generic::DescriptorCache cache; - generic::Context ctx(&cache); - - // Prime the initial generic context for current -> super_class - ctx.apply_type_arguments(current_class, super_class, CHECK_NULL); - - FindMethodsByGenericSig visitor(&cache, method_name, &ctx, CHECK_NULL); - visitor.run(super_class); - - GrowableArray families; - visitor.get_discovered_families(&families); - -#ifndef PRODUCT - if (TraceDefaultMethods) { - print_generic_families(&families, sig); - } -#endif // ndef PRODUCT - - GenericMethodFamily* selected_family = NULL; - - for (int i = 0; i < families.length(); ++i) { - GenericMethodFamily* lm = families.at(i); - if (lm->contains_signature(sig)) { - lm->determine_target(current_class, CHECK_NULL); - selected_family = lm; - } - } - - if (selected_family->has_target()) { - Method* target = selected_family->get_selected_target(); - InstanceKlass* holder = InstanceKlass::cast(target->method_holder()); - - // Verify that the identified method is valid from the context of - // the current class - GenericShadowChecker checker(&cache, THREAD, target->name(), - holder, selected_family->descriptor(), super_class); - checker.run(current_class); - - if (checker.found_shadow()) { -#ifndef PRODUCT - if (TraceDefaultMethods) { - tty->print_cr(" Only candidate found was shadowed."); - } -#endif // ndef PRODUCT - THROW_MSG_(vmSymbols::java_lang_AbstractMethodError(), - "Accessible default method not found", NULL); - } else { - return target; - } - } else { - assert(selected_family->throws_exception(), "must have target or throw"); - THROW_MSG_(vmSymbols::java_lang_AbstractMethodError(), - selected_family->get_exception_message()->as_C_string(), NULL); - } -} - // This is called during linktime when we find an invokespecial call that // refers to a direct superinterface. It indicates that we should find the // default method in the hierarchy of that superinterface, and if that method @@ -1296,13 +954,8 @@ assert(super_class->is_interface(), "only call for default methods"); Method* target = NULL; - if (ParseGenericDefaults) { - target = find_generic_super_default(current_class, super_class, - method_name, sig, CHECK_NULL); - } else { - target = find_erased_super_default(current_class, super_class, - method_name, sig, CHECK_NULL); - } + target = find_erased_super_default(current_class, super_class, + method_name, sig, CHECK_NULL); #ifndef PRODUCT if (target != NULL) {