JavaScriptCore-7601.1.46.3.tar.gz

[apple/javascriptcore.git] / dfg / DFGStoreBarrierElisionPhase.cpp

diff --git a/dfg/DFGStoreBarrierElisionPhase.cpp b/dfg/DFGStoreBarrierElisionPhase.cpp
deleted file mode 100644 (file)
index 4217552..0000000
--- a/dfg/DFGStoreBarrierElisionPhase.cpp
+++ /dev/null
@@ -1,154 +0,0 @@
-/*
- * 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. AND ITS CONTRIBUTORS ``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 ITS 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.
- */
-
-#include "config.h"
-#include "DFGStoreBarrierElisionPhase.h"
-
-#if ENABLE(DFG_JIT)
-
-#include "DFGBasicBlock.h"
-#include "DFGClobberize.h"
-#include "DFGGraph.h"
-#include "DFGPhase.h"
-#include "JSCInlines.h"
-#include <wtf/HashSet.h>
-
-namespace JSC { namespace DFG {
-
-class StoreBarrierElisionPhase : public Phase {
-public:
-    StoreBarrierElisionPhase(Graph& graph)
-        : Phase(graph, "store barrier elision")
-        , m_currentBlock(0)
-        , m_currentIndex(0)
-    {
-    }
-
-    bool run()
-    {
-        for (BlockIndex blockIndex = 0; blockIndex < m_graph.numBlocks(); ++blockIndex) {
-            m_currentBlock = m_graph.block(blockIndex);
-            if (!m_currentBlock)
-                continue;
-            handleBlock(m_currentBlock);
-        }
-        return true;
-    }
-
-private:
-    bool couldCauseGC(Node* node)
-    {
-        return writesOverlap(m_graph, node, GCState);
-    }
-
-    bool allocatesFreshObject(Node* node)
-    {
-        switch (node->op()) {
-        case NewObject:
-        case NewArray:
-        case NewArrayWithSize:
-        case NewArrayBuffer:
-        case NewTypedArray:
-        case NewRegexp:
-            return true;
-        default:
-            return false;
-        }
-    }
-
-    void noticeFreshObject(HashSet<Node*>& dontNeedBarriers, Node* node)
-    {
-        ASSERT(allocatesFreshObject(node));
-        dontNeedBarriers.add(node);
-    }
-
-    Node* getBaseOfStore(Node* barrierNode)
-    {
-        ASSERT(barrierNode->isStoreBarrier());
-        return barrierNode->child1().node();
-    }
-
-    bool shouldBeElided(HashSet<Node*>& dontNeedBarriers, Node* node)
-    {
-        ASSERT(node->isStoreBarrier());
-        return dontNeedBarriers.contains(node->child1().node());
-    }
-
-    void elideBarrier(Node* node)
-    {
-        ASSERT(node->isStoreBarrier());
-        node->convertToPhantom();
-    }
-
-    void handleNode(HashSet<Node*>& dontNeedBarriers, Node* node)
-    {
-        if (couldCauseGC(node))
-            dontNeedBarriers.clear();
-
-        if (allocatesFreshObject(node))
-            noticeFreshObject(dontNeedBarriers, node);
-
-        if (!node->isStoreBarrier())
-            return;
-
-        if (shouldBeElided(dontNeedBarriers, node)) {
-            elideBarrier(node);
-            return;
-        }
-
-        Node* base = getBaseOfStore(node);
-        if (!base)
-            return;
-
-        if (dontNeedBarriers.contains(base))
-            return;
-        dontNeedBarriers.add(base);
-    }
-
-    bool handleBlock(BasicBlock* block)
-    {
-        HashSet<Node*> dontNeedBarriers;
-        for (unsigned indexInBlock = 0; indexInBlock < block->size(); ++indexInBlock) {
-            m_currentIndex = indexInBlock;
-            Node* node = block->at(indexInBlock);
-            handleNode(dontNeedBarriers, node);
-        }
-        return true;
-    }
-
-    BasicBlock* m_currentBlock;
-    unsigned m_currentIndex;
-};
-    
-bool performStoreBarrierElision(Graph& graph)
-{
-    SamplingRegion samplingRegion("DFG Store Barrier Elision Phase");
-    return runPhase<StoreBarrierElisionPhase>(graph);
-}
-
-
-} } // namespace JSC::DFG
-
-#endif // ENABLE(DFG_JIT)