Source/JavaScriptCore/dfg/DFGEdgeDominates.h

/*
 * Copyright (C) 2013-2019 Apple Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#pragma once

#if ENABLE(DFG_JIT)

#include "DFGGraph.h"

namespace JSC { namespace DFG {

class EdgeDominates {
    static constexpr bool verbose = false;
    
public:
    EdgeDominates(Graph& graph, BasicBlock* block)
        : m_graph(graph)
        , m_block(block)
        , m_result(true)
    {
        ASSERT(graph.m_form == SSA);
    }
    
    void operator()(Node*, Edge edge)
    {
        bool result = m_graph.m_ssaDominators->dominates(edge.node()->owner, m_block);
        if (verbose) {
            dataLog(
                "Checking if ", edge, " in ", *edge.node()->owner,
                " dominates ", *m_block, ": ", result, "\n");
        }
        m_result &= result;
    }
    
    bool result() const { return m_result; }

private:
    Graph& m_graph;
    BasicBlock* m_block;
    bool m_result;
};

inline bool edgesDominate(Graph& graph, Node* node, BasicBlock* block)
{
    EdgeDominates edgeDominates(graph, block);
    DFG_NODE_DO_TO_CHILDREN(graph, node, edgeDominates);
    return edgeDominates.result();
}

} } // namespace JSC::DFG

#endif // ENABLE(DFG_JIT)