X-Git-Url: https://git.saurik.com/apple/javascriptcore.git/blobdiff_plain/a253471d7f8e4d91bf6ebabab00155c3b387d3d0..93a3786624b2768d89bfa27e46598dc64e2fb70a:/bytecode/PolymorphicAccessStructureList.h diff --git a/bytecode/PolymorphicAccessStructureList.h b/bytecode/PolymorphicAccessStructureList.h new file mode 100644 index 0000000..d1da89d --- /dev/null +++ b/bytecode/PolymorphicAccessStructureList.h @@ -0,0 +1,139 @@ +/* + * Copyright (C) 2013 Apple Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY + * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef PolymorphicAccessStructureList_h +#define PolymorphicAccessStructureList_h + +#include "JITStubRoutine.h" +#include "Structure.h" +#include "StructureChain.h" +#include + +#define POLYMORPHIC_LIST_CACHE_SIZE 8 + +namespace JSC { + +// *Sigh*, If the JIT is enabled we need to track the stubRountine (of type CodeLocationLabel), +// If the JIT is not in use we don't actually need the variable (that said, if the JIT is not in use we don't +// curently actually use PolymorphicAccessStructureLists, which we should). Anyway, this seems like the best +// solution for now - will need to something smarter if/when we actually want mixed-mode operation. + +#if ENABLE(JIT) +// Structure used by op_get_by_id_self_list and op_get_by_id_proto_list instruction to hold data off the main opcode stream. +struct PolymorphicAccessStructureList { + WTF_MAKE_FAST_ALLOCATED; +public: + struct PolymorphicStubInfo { + bool isChain; + bool isDirect; + RefPtr stubRoutine; + WriteBarrier base; + union { + WriteBarrierBase proto; + WriteBarrierBase chain; + } u; + + PolymorphicStubInfo() + { + u.proto.clear(); + } + + void set(VM& vm, JSCell* owner, PassRefPtr _stubRoutine, Structure* _base, bool isDirect) + { + stubRoutine = _stubRoutine; + base.set(vm, owner, _base); + u.proto.clear(); + isChain = false; + this->isDirect = isDirect; + } + + void set(VM& vm, JSCell* owner, PassRefPtr _stubRoutine, Structure* _base, Structure* _proto, bool isDirect) + { + stubRoutine = _stubRoutine; + base.set(vm, owner, _base); + u.proto.set(vm, owner, _proto); + isChain = false; + this->isDirect = isDirect; + } + + void set(VM& vm, JSCell* owner, PassRefPtr _stubRoutine, Structure* _base, StructureChain* _chain, bool isDirect) + { + stubRoutine = _stubRoutine; + base.set(vm, owner, _base); + u.chain.set(vm, owner, _chain); + isChain = true; + this->isDirect = isDirect; + } + } list[POLYMORPHIC_LIST_CACHE_SIZE]; + + PolymorphicAccessStructureList() + { + } + + PolymorphicAccessStructureList(VM& vm, JSCell* owner, PassRefPtr stubRoutine, Structure* firstBase, bool isDirect) + { + list[0].set(vm, owner, stubRoutine, firstBase, isDirect); + } + + PolymorphicAccessStructureList(VM& vm, JSCell* owner, PassRefPtr stubRoutine, Structure* firstBase, Structure* firstProto, bool isDirect) + { + list[0].set(vm, owner, stubRoutine, firstBase, firstProto, isDirect); + } + + PolymorphicAccessStructureList(VM& vm, JSCell* owner, PassRefPtr stubRoutine, Structure* firstBase, StructureChain* firstChain, bool isDirect) + { + list[0].set(vm, owner, stubRoutine, firstBase, firstChain, isDirect); + } + + bool visitWeak(int count) + { + for (int i = 0; i < count; ++i) { + PolymorphicStubInfo& info = list[i]; + if (!info.base) { + // We're being marked during initialisation of an entry + ASSERT(!info.u.proto); + continue; + } + + if (!Heap::isMarked(info.base.get())) + return false; + if (info.u.proto && !info.isChain + && !Heap::isMarked(info.u.proto.get())) + return false; + if (info.u.chain && info.isChain + && !Heap::isMarked(info.u.chain.get())) + return false; + } + + return true; + } +}; + +#endif // ENABLE(JIT) + +} // namespace JSC + +#endif // PolymorphicAccessStructureList_h +