| | 1 | /* |
| | 2 | * Copyright (C) 2011, 2014 Apple Inc. All rights reserved. |
| | 3 | * |
| | 4 | * Redistribution and use in source and binary forms, with or without |
| | 5 | * modification, are permitted provided that the following conditions |
| | 6 | * are met: |
| | 7 | * 1. Redistributions of source code must retain the above copyright |
| | 8 | * notice, this list of conditions and the following disclaimer. |
| | 9 | * 2. Redistributions in binary form must reproduce the above copyright |
| | 10 | * notice, this list of conditions and the following disclaimer in the |
| | 11 | * documentation and/or other materials provided with the distribution. |
| | 12 | * |
| | 13 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| | 14 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| | 15 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| | 16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| | 17 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| | 18 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| | 19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| | 20 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| | 21 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| | 22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| | 23 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| | 24 | */ |
| | 25 | |
| | 26 | #ifndef DFGCSEPhase_h |
| | 27 | #define DFGCSEPhase_h |
| | 28 | |
| | 29 | #if ENABLE(DFG_JIT) |
| | 30 | |
| | 31 | #include "DFGCommon.h" |
| | 32 | |
| | 33 | namespace JSC { namespace DFG { |
| | 34 | |
| | 35 | class Graph; |
| | 36 | |
| | 37 | // Block-local common subexpression elimination. It uses clobberize() for heap |
| | 38 | // modeling, which is quite precise. This phase is known to produce big wins on |
| | 39 | // a few benchmarks, and is relatively cheap to run. |
| | 40 | // |
| | 41 | // Note that this phase also gets rid of Identity nodes, which means that it's |
| | 42 | // currently not an optional phase. Basically, DFG IR doesn't have use-lists, |
| | 43 | // so there is no instantaneous replaceAllUsesWith operation. Instead, you turn |
| | 44 | // a node into an Identity and wait for CSE to clean it up. |
| | 45 | bool performLocalCSE(Graph&); |
| | 46 | |
| | 47 | // Same, but global. Only works for SSA. This will find common subexpressions |
| | 48 | // both in the same block and in any block that dominates the current block. It |
| | 49 | // has no limits on how far it will look for load-elimination opportunities. |
| | 50 | bool performGlobalCSE(Graph&); |
| | 51 | |
| | 52 | } } // namespace JSC::DFG |
| | 53 | |
| | 54 | #endif // ENABLE(DFG_JIT) |
| | 55 | |
| | 56 | #endif // DFGCSEPhase_h |
| | 57 | |
projects / apple / javascriptcore.git / blame_incremental