Source/JavaScriptCore/wasm/WasmBranchHints.h

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#pragma once

#include <wtf/HashMap.h>

namespace JSC {
namespace Wasm {

enum class BranchHint : uint8_t {
    Unlikely,
    Likely,
    Invalid,
};

class BranchHintMap {

public:

    void add(uint32_t branchOffset, BranchHint hint)
    {
        m_map.add(branchOffset, hint);
    }

    BranchHint getBranchHint(uint32_t branchOffset) const
    {
        auto it = m_map.find(branchOffset);
        if (it == m_map.end())
            return BranchHint::Invalid;
        return it->value;
    }

    bool isValidKey(uint32_t branchOffset) const
    {
        return m_map.isValidKey(branchOffset);
    }

private:

    HashMap<uint32_t, BranchHint, IntHash<uint32_t>, WTF::UnsignedWithZeroKeyHashTraits<uint32_t>> m_map;

};

inline constexpr bool isValidBranchHint(BranchHint hint)
{
    switch (hint) {
    case BranchHint::Likely:
    case BranchHint::Unlikely:
        return true;
    default:
        return false;
    }
    return false;
}

}
} // namespace JSC::Wasm