diff --git a/src/hotspot/share/gc/shared/c2/modRefBarrierSetC2.cpp b/src/hotspot/share/gc/shared/c2/modRefBarrierSetC2.cpp new file mode 100644 index 0000000..5b3b42a --- /dev/null +++ b/src/hotspot/share/gc/shared/c2/modRefBarrierSetC2.cpp @@ -0,0 +1,135 @@ +/* + * Copyright (c) 2018, 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 "opto/arraycopynode.hpp" +#include "opto/graphKit.hpp" +#include "opto/idealKit.hpp" +#include "opto/narrowptrnode.hpp" +#include "gc/shared/c2/modRefBarrierSetC2.hpp" +#include "utilities/macros.hpp" + +Node* ModRefBarrierSetC2::store_at_resolved(C2Access& access, C2AccessValue& val) const { + DecoratorSet decorators = access.decorators(); + GraphKit* kit = access.kit(); + + const TypePtr* adr_type = access.addr().type(); + Node* adr = access.addr().node(); + + bool on_array = (decorators & IN_HEAP_ARRAY) != 0; + bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; + bool on_heap = (decorators & IN_HEAP) != 0; + bool use_precise = on_array || anonymous; + + if (!access.is_oop() || (!on_heap && !anonymous)) { + return BarrierSetC2::store_at_resolved(access, val); + } + + uint adr_idx = kit->C->get_alias_index(adr_type); + assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); + + pre_barrier(kit, true /* do_load */, kit->control(), access.base(), adr, adr_idx, val.node(), + static_cast(val.type()), NULL /* pre_val */, access.type()); + Node* store = BarrierSetC2::store_at_resolved(access, val); + post_barrier(kit, kit->control(), access.raw_access(), access.base(), adr, adr_idx, val.node(), + access.type(), use_precise); + + return store; +} + +Node* ModRefBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicAccess& access, Node* expected_val, + Node* new_val, const Type* value_type) const { + GraphKit* kit = access.kit(); + + if (!access.is_oop()) { + return BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type); + } + + pre_barrier(kit, false /* do_load */, + kit->control(), NULL, NULL, max_juint, NULL, NULL, + expected_val /* pre_val */, T_OBJECT); + + Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type); + + post_barrier(kit, kit->control(), access.raw_access(), access.base(), + access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true); + + return result; +} + +Node* ModRefBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& access, Node* expected_val, + Node* new_val, const Type* value_type) const { + GraphKit* kit = access.kit(); + + if (!access.is_oop()) { + return BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type); + } + + pre_barrier(kit, false /* do_load */, + kit->control(), NULL, NULL, max_juint, NULL, NULL, + expected_val /* pre_val */, T_OBJECT); + + Node* load_store = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type); + + // Emit the post barrier only when the actual store happened. This makes sense + // to check only for LS_cmp_* that can fail to set the value. + // LS_cmp_exchange does not produce any branches by default, so there is no + // boolean result to piggyback on. TODO: When we merge CompareAndSwap with + // CompareAndExchange and move branches here, it would make sense to conditionalize + // post_barriers for LS_cmp_exchange as well. + // + // CAS success path is marked more likely since we anticipate this is a performance + // critical path, while CAS failure path can use the penalty for going through unlikely + // path as backoff. Which is still better than doing a store barrier there. + IdealKit ideal(kit); + ideal.if_then(load_store, BoolTest::ne, ideal.ConI(0), PROB_STATIC_FREQUENT); { + kit->sync_kit(ideal); + post_barrier(kit, ideal.ctrl(), access.raw_access(), access.base(), + access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true); + ideal.sync_kit(kit); + } ideal.end_if(); + kit->final_sync(ideal); + + return load_store; +} + +Node* ModRefBarrierSetC2::atomic_xchg_at_resolved(C2AtomicAccess& access, Node* new_val, const Type* value_type) const { + GraphKit* kit = access.kit(); + + Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, value_type); + if (!access.is_oop()) { + return result; + } + + // Don't need to load pre_val. The old value is returned by load_store. + // The pre_barrier can execute after the xchg as long as no safepoint + // gets inserted between them. + pre_barrier(kit, false /* do_load */, + kit->control(), NULL, NULL, max_juint, NULL, NULL, + result /* pre_val */, T_OBJECT); + post_barrier(kit, kit->control(), access.raw_access(), access.base(), access.addr().node(), + access.alias_idx(), new_val, T_OBJECT, true); + + return result; +}