Source/JavaScriptCore/wasm/WasmMergedProfile.h

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#pragma once

#if ENABLE(WEBASSEMBLY)

#include <JavaScriptCore/WasmBaselineData.h>
#include <JavaScriptCore/WasmCallProfile.h>
#include <JavaScriptCore/WasmCallee.h>
#include <wtf/StdLibExtras.h>
#include <wtf/text/WTFString.h>

namespace JSC::Wasm {

class Module;

class MergedProfile {
    WTF_MAKE_TZONE_ALLOCATED(MergedProfile);
    WTF_MAKE_NONMOVABLE(MergedProfile);
    friend class Module;
public:
    class Candidates {
    public:
        Candidates() = default;

        std::span<const std::tuple<Callee*, uint32_t>> callees() const LIFETIME_BOUND
        {
            return std::span { m_callees }.first(m_size);
        }

        bool isCalled() const { return !!m_totalCount; }
        bool isEmpty() const { return !m_size; }
        bool isMegamorphic() const { return m_isMegamorphic; }
        uint32_t totalCount() const { return m_totalCount; }

        void merge(IPIntCallee*, const CallProfile&);
        Candidates finalize() const;

    private:
        bool add(Callee*, uint32_t);
        void markAsMegamorphic(uint32_t count);

        uint32_t m_totalCount { 0 };
        uint8_t m_size { 0 };
        bool m_isMegamorphic { false };
        std::array<std::tuple<Callee*, uint32_t>, CallProfile::maxPolymorphicCallees> m_callees { };
    };

    MergedProfile(const IPIntCallee&);
    unsigned size() const { return m_callSites.size(); }
    bool isCalled(size_t index) const { return m_callSites[index].isCalled(); }
    Candidates candidates(size_t index) const { return m_callSites[index].finalize(); }
    bool isMegamorphic(size_t index) const { return m_callSites[index].isMegamorphic(); }

    void merge(const Module&, const IPIntCallee&, BaselineData&);
    bool merged() const { return m_merged; }
    uint32_t totalCount() const { return m_totalCount; }

private:
    Vector<Candidates> m_callSites;
    uint32_t m_totalCount { 0 };
    bool m_merged { false };
};

} // namespace JSC::Wasm

#endif // ENABLE(WEBASSEMBLY)