/* * Copyright (C) 2013, 2015 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. */ #pragma once #if ENABLE(DFG_JIT) namespace JSC { namespace DFG { // Tells you if an operation that filters type (i.e. does a type check/speculation) will always // exit. Formally, this means that the proven type of a value prior to the filter was not // bottom (i.e. not "clear" or "SpecEmpty") but becomes bottom as a result of executing the // filter. // // Note that per this definition, a filter will not return Contradiction if the node's proven // type was already bottom. This is necessary because we have this yucky convention of using // a proven type of bottom for nodes that don't hold JS values, like Phi nodes in ThreadedCPS // and storage nodes. enum FiltrationResult { // Means that this operation may not always exit. FiltrationOK, // Means that this operation will always exit. Contradiction }; } } // namespace JSC::DFG #endif // ENABLE(DFG_JIT)