BitArithmetic.cs

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namespace System.Reflection.Internal;
 
internal static class BitArithmetic
{
    internal static int CountBits(int v)
    {
        return CountBits((uint)v);
    }
 
    internal static int CountBits(uint v)
    {
        v -= (v >> 1) & 0x55555555;
        v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
        return (int)(((v + (v >> 4)) & 0xF0F0F0F) * 16843009) >> 24;
    }
 
    internal static int CountBits(ulong v)
    {
        v -= (v >> 1) & 0x5555555555555555L;
        v = (v & 0x3333333333333333L) + ((v >> 2) & 0x3333333333333333L);
        return (int)(((v + (v >> 4)) & 0xF0F0F0F0F0F0F0FL) * 72340172838076673L >> 56);
    }
 
    internal static uint Align(uint position, uint alignment)
    {
        uint num = position & ~(alignment - 1);
        if (num == position)
        {
            return num;
        }
        return num + alignment;
    }
 
    internal static int Align(int position, int alignment)
    {
        int num = position & ~(alignment - 1);
        if (num == position)
        {
            return num;
        }
        return num + alignment;
    }
}