| /* |
| * 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) |
