/* * Copyright (C) 2011, 2014 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) #include "DFGCommon.h" namespace JSC { namespace DFG { class Graph; // Block-local common subexpression elimination. It uses clobberize() for heap // modeling, which is quite precise. This phase is known to produce big wins on // a few benchmarks, and is relatively cheap to run. // // Note that this phase also gets rid of Identity nodes, which means that it's // currently not an optional phase. Basically, DFG IR doesn't have use-lists, // so there is no instantaneous replaceAllUsesWith operation. Instead, you turn // a node into an Identity and wait for CSE to clean it up. bool performLocalCSE(Graph&); // Same, but global. Only works for SSA. This will find common subexpressions // both in the same block and in any block that dominates the current block. It // has no limits on how far it will look for load-elimination opportunities. bool performGlobalCSE(Graph&); } } // namespace JSC::DFG #endif // ENABLE(DFG_JIT)