Re: Byte Order Swapping Function

[Piotr Szturmaj]

Jonathan M Davis wrote:
private T swapEndianImpl(T)(T val)
     if(is(Unqual!T == ulong))
{
     return ((val&  0xff00000000000000UL)>>  56) |
            ((val&  0x00ff000000000000UL)>>  40) |
            ((val&  0x0000ff0000000000UL)>>  24) |
            ((val&  0x000000ff00000000UL)>>  8) |
            ((val&  0x00000000ff000000UL)<<  8) |
            ((val&  0x0000000000ff0000UL)<<  24) |
            ((val&  0x000000000000ff00UL)<<  40) |
            ((val&  0x00000000000000ffUL)<<  56);
}

Here's shorter version that I use:

@safe pure nothrow ulong bswap(ulong i)
{
    i = (i >> 32) | (i << 32);
    i = ((i & 0xff00ff00ff00ff00) >> 8) | ((i & 0x00ff00ff00ff00ff) << 8);
    return ((i & 0xffff0000ffff0000) >> 16) | ((i & 0x0000ffff0000ffff) 
<< 16);
}