/* * Copyright (c) 1998, 2015, 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. * */ #include "precompiled.hpp" #include "interpreter/interpreter.hpp" #include "interpreter/rewriter.hpp" #include "memory/universe.inline.hpp" #include "oops/cpCache.hpp" #include "oops/objArrayOop.inline.hpp" #include "oops/oop.inline.hpp" #include "prims/jvmtiRedefineClassesTrace.hpp" #include "prims/methodHandles.hpp" #include "runtime/atomic.inline.hpp" #include "runtime/handles.inline.hpp" #include "runtime/orderAccess.inline.hpp" #include "utilities/macros.hpp" PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC // Implementation of ConstantPoolCacheEntry void ConstantPoolCacheEntry::initialize_entry(int index) { assert(0 < index && index < 0x10000, "sanity check"); _indices = index; _f1 = NULL; _f2 = _flags = 0; assert(constant_pool_index() == index, ""); } int ConstantPoolCacheEntry::make_flags(TosState state, int option_bits, int field_index_or_method_params) { assert(state < number_of_states, "Invalid state in make_flags"); int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params; // Preserve existing flag bit values // The low bits are a field offset, or else the method parameter size. #ifdef ASSERT TosState old_state = flag_state(); assert(old_state == (TosState)0 || old_state == state, "inconsistent cpCache flags state"); #endif return (_flags | f) ; } void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) { #ifdef ASSERT // Read once. volatile Bytecodes::Code c = bytecode_1(); assert(c == 0 || c == code || code == 0, "update must be consistent"); #endif // Need to flush pending stores here before bytecode is written. OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_1_shift)); } void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) { #ifdef ASSERT // Read once. volatile Bytecodes::Code c = bytecode_2(); assert(c == 0 || c == code || code == 0, "update must be consistent"); #endif // Need to flush pending stores here before bytecode is written. OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_2_shift)); } // Sets f1, ordering with previous writes. void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) { assert(f1 != NULL, ""); OrderAccess::release_store_ptr((HeapWord*) &_f1, f1); } // Sets flags, but only if the value was previously zero. bool ConstantPoolCacheEntry::init_flags_atomic(intptr_t flags) { intptr_t result = Atomic::cmpxchg_ptr(flags, &_flags, 0); return (result == 0); } // Note that concurrent update of both bytecodes can leave one of them // reset to zero. This is harmless; the interpreter will simply re-resolve // the damaged entry. More seriously, the memory synchronization is needed // to flush other fields (f1, f2) completely to memory before the bytecodes // are updated, lest other processors see a non-zero bytecode but zero f1/f2. void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code, Bytecodes::Code put_code, KlassHandle field_holder, int field_index, int field_offset, TosState field_type, bool is_final, bool is_volatile, Klass* root_klass) { set_f1(field_holder()); set_f2(field_offset); assert((field_index & field_index_mask) == field_index, "field index does not fit in low flag bits"); set_field_flags(field_type, ((is_volatile ? 1 : 0) << is_volatile_shift) | ((is_final ? 1 : 0) << is_final_shift), field_index); set_bytecode_1(get_code); set_bytecode_2(put_code); NOT_PRODUCT(verify(tty)); } void ConstantPoolCacheEntry::set_parameter_size(int value) { // This routine is called only in corner cases where the CPCE is not yet initialized. // See AbstractInterpreter::deopt_continue_after_entry. assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value, err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value)); // Setting the parameter size by itself is only safe if the // current value of _flags is 0, otherwise another thread may have // updated it and we don't want to overwrite that value. Don't // bother trying to update it once it's nonzero but always make // sure that the final parameter size agrees with what was passed. if (_flags == 0) { Atomic::cmpxchg_ptr((value & parameter_size_mask), &_flags, 0); } guarantee(parameter_size() == value, err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value)); } void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code, methodHandle method, int vtable_index) { bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean assert(method->interpreter_entry() != NULL, "should have been set at this point"); assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache"); int byte_no = -1; bool change_to_virtual = false; switch (invoke_code) { case Bytecodes::_invokeinterface: // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface // instruction somehow links to a non-interface method (in Object). // In that case, the method has no itable index and must be invoked as a virtual. // Set a flag to keep track of this corner case. change_to_virtual = true; // ...and fall through as if we were handling invokevirtual: case Bytecodes::_invokevirtual: { if (!is_vtable_call) { assert(method->can_be_statically_bound(), ""); // set_f2_as_vfinal_method checks if is_vfinal flag is true. set_method_flags(as_TosState(method->result_type()), ( 1 << is_vfinal_shift) | ((method->is_final_method() ? 1 : 0) << is_final_shift) | ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), method()->size_of_parameters()); set_f2_as_vfinal_method(method()); } else { assert(!method->can_be_statically_bound(), ""); assert(vtable_index >= 0, "valid index"); assert(!method->is_final_method(), "sanity"); set_method_flags(as_TosState(method->result_type()), ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), method()->size_of_parameters()); set_f2(vtable_index); } byte_no = 2; break; } case Bytecodes::_invokespecial: case Bytecodes::_invokestatic: assert(!is_vtable_call, ""); // Note: Read and preserve the value of the is_vfinal flag on any // invokevirtual bytecode shared with this constant pool cache entry. // It is cheap and safe to consult is_vfinal() at all times. // Once is_vfinal is set, it must stay that way, lest we get a dangling oop. set_method_flags(as_TosState(method->result_type()), ((is_vfinal() ? 1 : 0) << is_vfinal_shift) | ((method->is_final_method() ? 1 : 0) << is_final_shift), method()->size_of_parameters()); set_f1(method()); byte_no = 1; break; default: ShouldNotReachHere(); break; } // Note: byte_no also appears in TemplateTable::resolve. if (byte_no == 1) { assert(invoke_code != Bytecodes::_invokevirtual && invoke_code != Bytecodes::_invokeinterface, ""); set_bytecode_1(invoke_code); } else if (byte_no == 2) { if (change_to_virtual) { assert(invoke_code == Bytecodes::_invokeinterface, ""); // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! // // Workaround for the case where we encounter an invokeinterface, but we // should really have an _invokevirtual since the resolved method is a // virtual method in java.lang.Object. This is a corner case in the spec // but is presumably legal. javac does not generate this code. // // We set bytecode_1() to _invokeinterface, because that is the // bytecode # used by the interpreter to see if it is resolved. // We set bytecode_2() to _invokevirtual. // See also interpreterRuntime.cpp. (8/25/2000) // Only set resolved for the invokeinterface case if method is public. // Otherwise, the method needs to be reresolved with caller for each // interface call. if (method->is_public()) set_bytecode_1(invoke_code); } else { assert(invoke_code == Bytecodes::_invokevirtual, ""); } // set up for invokevirtual, even if linking for invokeinterface also: set_bytecode_2(Bytecodes::_invokevirtual); } else { ShouldNotReachHere(); } NOT_PRODUCT(verify(tty)); } void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, methodHandle method) { int index = Method::nonvirtual_vtable_index; // index < 0; FIXME: inline and customize set_direct_or_vtable_call set_direct_or_vtable_call(invoke_code, method, index); } void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, methodHandle method, int index) { // either the method is a miranda or its holder should accept the given index assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), ""); // index >= 0; FIXME: inline and customize set_direct_or_vtable_call set_direct_or_vtable_call(invoke_code, method, index); } void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, methodHandle method, int index) { assert(method->method_holder()->verify_itable_index(index), ""); assert(invoke_code == Bytecodes::_invokeinterface, ""); InstanceKlass* interf = method->method_holder(); assert(interf->is_interface(), "must be an interface"); assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here"); set_f1(interf); set_f2(index); set_method_flags(as_TosState(method->result_type()), 0, // no option bits method()->size_of_parameters()); set_bytecode_1(Bytecodes::_invokeinterface); } void ConstantPoolCacheEntry::set_method_handle(constantPoolHandle cpool, const CallInfo &call_info) { set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info); } void ConstantPoolCacheEntry::set_dynamic_call(constantPoolHandle cpool, const CallInfo &call_info) { set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info); } void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool, Bytecodes::Code invoke_code, const CallInfo &call_info) { // NOTE: This CPCE can be the subject of data races. // There are three words to update: flags, refs[f2], f1 (in that order). // Writers must store all other values before f1. // Readers must test f1 first for non-null before reading other fields. // Competing writers must acquire exclusive access via a lock. // A losing writer waits on the lock until the winner writes f1 and leaves // the lock, so that when the losing writer returns, he can use the linked // cache entry. objArrayHandle resolved_references = objArrayHandle(objArrayOop(oopDesc::bs()->write_barrier(cpool->resolved_references()))); // Use the resolved_references() lock for this cpCache entry. // resolved_references are created for all classes with Invokedynamic, MethodHandle // or MethodType constant pool cache entries. assert(resolved_references() != NULL, "a resolved_references array should have been created for this class"); ObjectLocker ol(resolved_references, Thread::current()); if (!is_f1_null()) { return; } const methodHandle adapter = call_info.resolved_method(); const Handle appendix = call_info.resolved_appendix(); const Handle method_type = call_info.resolved_method_type(); const bool has_appendix = appendix.not_null(); const bool has_method_type = method_type.not_null(); // Write the flags. set_method_flags(as_TosState(adapter->result_type()), ((has_appendix ? 1 : 0) << has_appendix_shift ) | ((has_method_type ? 1 : 0) << has_method_type_shift) | ( 1 << is_final_shift ), adapter->size_of_parameters()); if (TraceInvokeDynamic) { tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ", invoke_code, (void *)appendix(), (has_appendix ? "" : " (unused)"), (void *)method_type(), (has_method_type ? "" : " (unused)"), (intptr_t)adapter()); adapter->print(); if (has_appendix) appendix()->print(); } // Method handle invokes and invokedynamic sites use both cp cache words. // refs[f2], if not null, contains a value passed as a trailing argument to the adapter. // In the general case, this could be the call site's MethodType, // for use with java.lang.Invokers.checkExactType, or else a CallSite object. // f1 contains the adapter method which manages the actual call. // In the general case, this is a compiled LambdaForm. // (The Java code is free to optimize these calls by binding other // sorts of methods and appendices to call sites.) // JVM-level linking is via f1, as if for invokespecial, and signatures are erased. // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. // Even with the appendix, the method will never take more than 255 parameter slots. // // This means that given a call site like (List)mh.invoke("foo"), // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;', // not '(Ljava/lang/String;)Ljava/util/List;'. // The fact that String and List are involved is encoded in the MethodType in refs[f2]. // This allows us to create fewer Methods, while keeping type safety. // // Store appendix, if any. if (has_appendix) { const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset; assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob"); assert(resolved_references->obj_at(appendix_index) == NULL, "init just once"); resolved_references->obj_at_put(appendix_index, appendix()); } // Store MethodType, if any. if (has_method_type) { const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset; assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob"); assert(resolved_references->obj_at(method_type_index) == NULL, "init just once"); resolved_references->obj_at_put(method_type_index, method_type()); } release_set_f1(adapter()); // This must be the last one to set (see NOTE above)! // The interpreter assembly code does not check byte_2, // but it is used by is_resolved, method_if_resolved, etc. set_bytecode_1(invoke_code); NOT_PRODUCT(verify(tty)); if (TraceInvokeDynamic) { this->print(tty, 0); } } Method* ConstantPoolCacheEntry::method_if_resolved(constantPoolHandle cpool) { // Decode the action of set_method and set_interface_call Bytecodes::Code invoke_code = bytecode_1(); if (invoke_code != (Bytecodes::Code)0) { Metadata* f1 = f1_ord(); if (f1 != NULL) { switch (invoke_code) { case Bytecodes::_invokeinterface: assert(f1->is_klass(), ""); return klassItable::method_for_itable_index((Klass*)f1, f2_as_index()); case Bytecodes::_invokestatic: case Bytecodes::_invokespecial: assert(!has_appendix(), ""); case Bytecodes::_invokehandle: case Bytecodes::_invokedynamic: assert(f1->is_method(), ""); return (Method*)f1; } } } invoke_code = bytecode_2(); if (invoke_code != (Bytecodes::Code)0) { switch (invoke_code) { case Bytecodes::_invokevirtual: if (is_vfinal()) { // invokevirtual Method* m = f2_as_vfinal_method(); assert(m->is_method(), ""); return m; } else { int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index()); if (cpool->tag_at(holder_index).is_klass()) { Klass* klass = cpool->resolved_klass_at(holder_index); if (!klass->oop_is_instance()) klass = SystemDictionary::Object_klass(); return InstanceKlass::cast(klass)->method_at_vtable(f2_as_index()); } } break; } } return NULL; } oop ConstantPoolCacheEntry::appendix_if_resolved(constantPoolHandle cpool) { if (!has_appendix()) return NULL; const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset; objArrayOop resolved_references = cpool->resolved_references(); return resolved_references->obj_at(ref_index); } oop ConstantPoolCacheEntry::method_type_if_resolved(constantPoolHandle cpool) { if (!has_method_type()) return NULL; const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset; objArrayOop resolved_references = cpool->resolved_references(); return resolved_references->obj_at(ref_index); } #if INCLUDE_JVMTI // RedefineClasses() API support: // If this ConstantPoolCacheEntry refers to old_method then update it // to refer to new_method. bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method, Method* new_method, bool * trace_name_printed) { if (is_vfinal()) { // virtual and final so _f2 contains method ptr instead of vtable index if (f2_as_vfinal_method() == old_method) { // match old_method so need an update // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values _f2 = (intptr_t)new_method; if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { if (!(*trace_name_printed)) { // RC_TRACE_MESG macro has an embedded ResourceMark RC_TRACE_MESG(("adjust: name=%s", old_method->method_holder()->external_name())); *trace_name_printed = true; } // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string())); } return true; } // f1() is not used with virtual entries so bail out return false; } if (_f1 == NULL) { // NULL f1() means this is a virtual entry so bail out // We are assuming that the vtable index does not need change. return false; } if (_f1 == old_method) { _f1 = new_method; if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { if (!(*trace_name_printed)) { // RC_TRACE_MESG macro has an embedded ResourceMark RC_TRACE_MESG(("adjust: name=%s", old_method->method_holder()->external_name())); *trace_name_printed = true; } // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00400000, ("cpc entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string())); } return true; } return false; } // a constant pool cache entry should never contain old or obsolete methods bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() { if (is_vfinal()) { // virtual and final so _f2 contains method ptr instead of vtable index Metadata* f2 = (Metadata*)_f2; // Return false if _f2 refers to an old or an obsolete method. // _f2 == NULL || !_f2->is_method() are just as unexpected here. return (f2 != NULL NOT_PRODUCT(&& f2->is_valid()) && f2->is_method() && !((Method*)f2)->is_old() && !((Method*)f2)->is_obsolete()); } else if (_f1 == NULL || (NOT_PRODUCT(_f1->is_valid() &&) !_f1->is_method())) { // _f1 == NULL || !_f1->is_method() are OK here return true; } // return false if _f1 refers to a non-deleted old or obsolete method return (NOT_PRODUCT(_f1->is_valid() &&) _f1->is_method() && (f1_as_method()->is_deleted() || (!f1_as_method()->is_old() && !f1_as_method()->is_obsolete()))); } Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) { if (!is_method_entry()) { // not a method entry so not interesting by default return NULL; } Method* m = NULL; if (is_vfinal()) { // virtual and final so _f2 contains method ptr instead of vtable index m = f2_as_vfinal_method(); } else if (is_f1_null()) { // NULL _f1 means this is a virtual entry so also not interesting return NULL; } else { if (!(_f1->is_method())) { // _f1 can also contain a Klass* for an interface return NULL; } m = f1_as_method(); } assert(m != NULL && m->is_method(), "sanity check"); if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) { // robustness for above sanity checks or method is not in // the interesting class return NULL; } // the method is in the interesting class so the entry is interesting return m; } #endif // INCLUDE_JVMTI void ConstantPoolCacheEntry::print(outputStream* st, int index) const { // print separator if (index == 0) st->print_cr(" -------------"); // print entry st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this); st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), constant_pool_index()); st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1); st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2); st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags); st->print_cr(" -------------"); } void ConstantPoolCacheEntry::verify(outputStream* st) const { // not implemented yet } // Implementation of ConstantPoolCache ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data, const intStack& index_map, const intStack& invokedynamic_index_map, const intStack& invokedynamic_map, TRAPS) { const int length = index_map.length() + invokedynamic_index_map.length(); int size = ConstantPoolCache::size(length); return new (loader_data, size, false, MetaspaceObj::ConstantPoolCacheType, THREAD) ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map); } void ConstantPoolCache::initialize(const intArray& inverse_index_map, const intArray& invokedynamic_inverse_index_map, const intArray& invokedynamic_references_map) { for (int i = 0; i < inverse_index_map.length(); i++) { ConstantPoolCacheEntry* e = entry_at(i); int original_index = inverse_index_map[i]; e->initialize_entry(original_index); assert(entry_at(i) == e, "sanity"); } // Append invokedynamic entries at the end int invokedynamic_offset = inverse_index_map.length(); for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) { int offset = i + invokedynamic_offset; ConstantPoolCacheEntry* e = entry_at(offset); int original_index = invokedynamic_inverse_index_map[i]; e->initialize_entry(original_index); assert(entry_at(offset) == e, "sanity"); } for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) { const int cpci = invokedynamic_references_map[ref]; if (cpci >= 0) { #ifdef ASSERT // invokedynamic and invokehandle have more entries; check if they // all point to the same constant pool cache entry. for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) { const int cpci_next = invokedynamic_references_map[ref + entry]; assert(cpci == cpci_next, err_msg_res("%d == %d", cpci, cpci_next)); } #endif entry_at(cpci)->initialize_resolved_reference_index(ref); ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries } } } #if INCLUDE_JVMTI // RedefineClasses() API support: // If any entry of this ConstantPoolCache points to any of // old_methods, replace it with the corresponding new_method. void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) { for (int i = 0; i < length(); i++) { ConstantPoolCacheEntry* entry = entry_at(i); Method* old_method = entry->get_interesting_method_entry(holder); if (old_method == NULL || !old_method->is_old()) { continue; // skip uninteresting entries } if (old_method->is_deleted()) { // clean up entries with deleted methods entry->initialize_entry(entry->constant_pool_index()); continue; } Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); assert(new_method != NULL, "method_with_idnum() should not be NULL"); assert(old_method != new_method, "sanity check"); entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed); } } // the constant pool cache should never contain old or obsolete methods bool ConstantPoolCache::check_no_old_or_obsolete_entries() { for (int i = 1; i < length(); i++) { if (entry_at(i)->get_interesting_method_entry(NULL) != NULL && !entry_at(i)->check_no_old_or_obsolete_entries()) { return false; } } return true; } void ConstantPoolCache::dump_cache() { for (int i = 1; i < length(); i++) { if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) { entry_at(i)->print(tty, i); } } } #endif // INCLUDE_JVMTI // Printing void ConstantPoolCache::print_on(outputStream* st) const { assert(is_constantPoolCache(), "obj must be constant pool cache"); st->print_cr("%s", internal_name()); // print constant pool cache entries for (int i = 0; i < length(); i++) entry_at(i)->print(st, i); } void ConstantPoolCache::print_value_on(outputStream* st) const { assert(is_constantPoolCache(), "obj must be constant pool cache"); st->print("cache [%d]", length()); print_address_on(st); st->print(" for "); constant_pool()->print_value_on(st); } // Verification void ConstantPoolCache::verify_on(outputStream* st) { guarantee(is_constantPoolCache(), "obj must be constant pool cache"); // print constant pool cache entries for (int i = 0; i < length(); i++) entry_at(i)->verify(st); }