HashTableCore.C

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License
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#include "HashTable.H"
#include "uLabel.H"

// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //

namespace Foam
{
defineTypeNameAndDebug(HashTableCore, 0);
}

const Foam::label Foam::HashTableCore::maxTableSize
(
    Foam::HashTableCore::canonicalSize
    (
        Foam::labelMax/2
    )
);


// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //

Foam::label Foam::HashTableCore::canonicalSize(const label size)
{
    if (size < 1)
    {
        return 0;
    }

    // enforce power of two
    uLabel goodSize = size;

    if (goodSize & (goodSize - 1))
    {
        // brute-force is fast enough
        goodSize = 1;
        while (goodSize < unsigned(size))
        {
            goodSize <<= 1;
        }
    }

    return goodSize;
}


// ************************************************************************* //