Mercurial > hg > graal-compiler
view src/share/vm/oops/cpCacheOop.cpp @ 6543:ec196bfc458b
Minor fixes after cleanup
author | Christian Wimmer <christian.wimmer@oracle.com> |
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date | Tue, 09 Oct 2012 16:16:39 -0700 |
parents | 1d7922586cf6 |
children |
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/* * Copyright (c) 1998, 2012, 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 "gc_implementation/shared/markSweep.inline.hpp" #include "interpreter/interpreter.hpp" #include "interpreter/rewriter.hpp" #include "memory/universe.inline.hpp" #include "oops/cpCacheOop.hpp" #include "oops/objArrayOop.hpp" #include "oops/oop.inline.hpp" #include "prims/jvmtiRedefineClassesTrace.hpp" #include "prims/methodHandles.hpp" #include "runtime/handles.inline.hpp" // Implememtation of ConstantPoolCacheEntry void ConstantPoolCacheEntry::initialize_entry(int index) { assert(0 < index && index < 0x10000, "sanity check"); _indices = index; assert(constant_pool_index() == index, ""); } void ConstantPoolCacheEntry::initialize_secondary_entry(int main_index) { assert(0 <= main_index && main_index < 0x10000, "sanity check"); _indices = (main_index << main_cp_index_bits); assert(main_entry_index() == main_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) { assert(!is_secondary_entry(), "must not overwrite main_entry_index"); #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) { assert(!is_secondary_entry(), "must not overwrite main_entry_index"); #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(oop f1) { // Use barriers as in oop_store assert(f1 != NULL, ""); oop* f1_addr = (oop*) &_f1; update_barrier_set_pre(f1_addr, f1); OrderAccess::release_store_ptr((intptr_t*)f1_addr, f1); update_barrier_set((void*) f1_addr, 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); } #ifdef ASSERT // It is possible to have two different dummy methodOops created // when the resolve code for invoke interface executes concurrently // Hence the assertion below is weakened a bit for the invokeinterface // case. bool ConstantPoolCacheEntry::same_methodOop(oop cur_f1, oop f1) { return (cur_f1 == f1 || ((methodOop)cur_f1)->name() == ((methodOop)f1)->name() || ((methodOop)cur_f1)->signature() == ((methodOop)f1)->signature()); } #endif // 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) { set_f1(field_holder()->java_mirror()); 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_method(Bytecodes::Code invoke_code, methodHandle method, int vtable_index) { assert(!is_secondary_entry(), ""); 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 (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(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: // 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_interface_call(methodHandle method, int index) { assert(!is_secondary_entry(), ""); klassOop interf = method->method_holder(); assert(instanceKlass::cast(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(methodHandle adapter, Handle appendix) { assert(!is_secondary_entry(), ""); set_method_handle_common(Bytecodes::_invokehandle, adapter, appendix); } void ConstantPoolCacheEntry::set_dynamic_call(methodHandle adapter, Handle appendix) { assert(is_secondary_entry(), ""); set_method_handle_common(Bytecodes::_invokedynamic, adapter, appendix); } void ConstantPoolCacheEntry::set_method_handle_common(Bytecodes::Code invoke_code, methodHandle adapter, Handle appendix) { // NOTE: This CPCE can be the subject of data races. // There are three words to update: flags, 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 on the first // write, to flags, using a compare/exchange. // A losing writer must spin until the winner writes f1, // so that when he returns, he can use the linked cache entry. bool has_appendix = appendix.not_null(); if (!has_appendix) { // The extra argument is not used, but we need a non-null value to signify linkage state. // Set it to something benign that will never leak memory. appendix = Universe::void_mirror(); } bool owner = init_method_flags_atomic(as_TosState(adapter->result_type()), ((has_appendix ? 1 : 0) << has_appendix_shift) | ( 1 << is_vfinal_shift) | ( 1 << is_final_shift), adapter->size_of_parameters()); if (!owner) { while (is_f1_null()) { // Pause momentarily on a low-level lock, to allow racing thread to win. MutexLockerEx mu(Patching_lock, Mutex::_no_safepoint_check_flag); os::yield(); } return; } if (TraceInvokeDynamic) { tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method="PTR_FORMAT" ", invoke_code, (intptr_t)appendix(), (has_appendix ? "" : " (unused)"), (intptr_t)adapter()); adapter->print(); if (has_appendix) appendix()->print(); } // Method handle invokes and invokedynamic sites use both cp cache words. // f1, 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. // f2 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 f2, as if for invokevfinal, and signatures are erased. // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. // In principle this means that the method (with appendix) could take up to 256 parameter slots. // // This means that given a call site like (List)mh.invoke("foo"), // the f2 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 f1. // This allows us to create fewer method oops, while keeping type safety. // set_f2_as_vfinal_method(adapter()); assert(appendix.not_null(), "needed for linkage state"); release_set_f1(appendix()); // This must be the last one to set (see NOTE above)! if (!is_secondary_entry()) { // The interpreter assembly code does not check byte_2, // but it is used by is_resolved, method_if_resolved, etc. set_bytecode_2(invoke_code); } NOT_PRODUCT(verify(tty)); if (TraceInvokeDynamic) { this->print(tty, 0); } } methodOop ConstantPoolCacheEntry::method_if_resolved(constantPoolHandle cpool) { if (is_secondary_entry()) { if (!is_f1_null()) return f2_as_vfinal_method(); return NULL; } // Decode the action of set_method and set_interface_call Bytecodes::Code invoke_code = bytecode_1(); if (invoke_code != (Bytecodes::Code)0) { oop f1 = _f1; if (f1 != NULL) { switch (invoke_code) { case Bytecodes::_invokeinterface: assert(f1->is_klass(), ""); return klassItable::method_for_itable_index(klassOop(f1), f2_as_index()); case Bytecodes::_invokestatic: case Bytecodes::_invokespecial: assert(!has_appendix(), ""); assert(f1->is_method(), ""); return methodOop(f1); } } } invoke_code = bytecode_2(); if (invoke_code != (Bytecodes::Code)0) { switch (invoke_code) { case Bytecodes::_invokevirtual: if (is_vfinal()) { // invokevirtual methodOop 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()) { klassOop klass = cpool->resolved_klass_at(holder_index); if (!Klass::cast(klass)->oop_is_instance()) klass = SystemDictionary::Object_klass(); return instanceKlass::cast(klass)->method_at_vtable(f2_as_index()); } } break; case Bytecodes::_invokehandle: case Bytecodes::_invokedynamic: return f2_as_vfinal_method(); } } return NULL; } class LocalOopClosure: public OopClosure { private: void (*_f)(oop*); public: LocalOopClosure(void f(oop*)) { _f = f; } virtual void do_oop(oop* o) { _f(o); } virtual void do_oop(narrowOop *o) { ShouldNotReachHere(); } }; void ConstantPoolCacheEntry::oops_do(void f(oop*)) { LocalOopClosure blk(f); oop_iterate(&blk); } void ConstantPoolCacheEntry::oop_iterate(OopClosure* blk) { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL blk->do_oop((oop*)&_f1); if (is_vfinal()) { blk->do_oop((oop*)&_f2); } } void ConstantPoolCacheEntry::oop_iterate_m(OopClosure* blk, MemRegion mr) { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL if (mr.contains((oop *)&_f1)) blk->do_oop((oop*)&_f1); if (is_vfinal()) { if (mr.contains((oop *)&_f2)) blk->do_oop((oop*)&_f2); } } void ConstantPoolCacheEntry::follow_contents() { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL MarkSweep::mark_and_push((oop*)&_f1); if (is_vfinal()) { MarkSweep::mark_and_push((oop*)&_f2); } } #ifndef SERIALGC void ConstantPoolCacheEntry::follow_contents(ParCompactionManager* cm) { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL PSParallelCompact::mark_and_push(cm, (oop*)&_f1); if (is_vfinal()) { PSParallelCompact::mark_and_push(cm, (oop*)&_f2); } } #endif // SERIALGC void ConstantPoolCacheEntry::adjust_pointers() { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL MarkSweep::adjust_pointer((oop*)&_f1); if (is_vfinal()) { MarkSweep::adjust_pointer((oop*)&_f2); } } #ifndef SERIALGC void ConstantPoolCacheEntry::update_pointers() { assert(in_words(size()) == 4, "check code below - may need adjustment"); // field[1] is always oop or NULL PSParallelCompact::adjust_pointer((oop*)&_f1); if (is_vfinal()) { PSParallelCompact::adjust_pointer((oop*)&_f2); } } #endif // SERIALGC // RedefineClasses() API support: // If this constantPoolCacheEntry refers to old_method then update it // to refer to new_method. bool ConstantPoolCacheEntry::adjust_method_entry(methodOop old_method, methodOop 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", Klass::cast(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 ((oop)_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 ((oop)_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", Klass::cast(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; } bool ConstantPoolCacheEntry::is_interesting_method_entry(klassOop k) { if (!is_method_entry()) { // not a method entry so not interesting by default return false; } methodOop 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 false; } else { oop f1 = _f1; // _f1 is volatile if (!f1->is_method()) { // _f1 can also contain a klassOop for an interface return false; } m = f1_as_method(); } assert(m != NULL && m->is_method(), "sanity check"); if (m == NULL || !m->is_method() || m->method_holder() != k) { // robustness for above sanity checks or method is not in // the interesting class return false; } // the method is in the interesting class so the entry is interesting return true; } 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); if (is_secondary_entry()) st->print_cr("[%5d|secondary]", main_entry_index()); else st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), constant_pool_index()); st->print_cr(" [ "PTR_FORMAT"]", (intptr_t)(oop)_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 void constantPoolCacheOopDesc::initialize(intArray& inverse_index_map) { assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache"); for (int i = 0; i < length(); i++) { ConstantPoolCacheEntry* e = entry_at(i); int original_index = inverse_index_map[i]; if ((original_index & Rewriter::_secondary_entry_tag) != 0) { int main_index = (original_index - Rewriter::_secondary_entry_tag); assert(!entry_at(main_index)->is_secondary_entry(), "valid main index"); e->initialize_secondary_entry(main_index); } else { e->initialize_entry(original_index); } assert(entry_at(i) == e, "sanity"); } } // RedefineClasses() API support: // If any entry of this constantPoolCache points to any of // old_methods, replace it with the corresponding new_method. void constantPoolCacheOopDesc::adjust_method_entries(methodOop* old_methods, methodOop* new_methods, int methods_length, bool * trace_name_printed) { if (methods_length == 0) { // nothing to do if there are no methods return; } // get shorthand for the interesting class klassOop old_holder = old_methods[0]->method_holder(); for (int i = 0; i < length(); i++) { if (!entry_at(i)->is_interesting_method_entry(old_holder)) { // skip uninteresting methods continue; } // The constantPoolCache contains entries for several different // things, but we only care about methods. In fact, we only care // about methods in the same class as the one that contains the // old_methods. At this point, we have an interesting entry. for (int j = 0; j < methods_length; j++) { methodOop old_method = old_methods[j]; methodOop new_method = new_methods[j]; if (entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed)) { // current old_method matched this entry and we updated it so // break out and get to the next interesting entry if there one break; } } } }