Decimal to Binary - Optimising

[wossname]

Following JMC's lead I thought it would be fun to do it in C#.

The code is longer but its actually about 5 times faster. No concatenation, no floating point operations. I have used uint's instead of int32's because there is no requirement for converting negative numbers and the largest number containable is twice as large.

I know its in C# but that's the idea, C# lets you use pointers and unmanaged arrays and stuf like that. I just benchmarked this and it runs 1,000,000 (1 million) times in an average time of 0.66 seconds on my old, slow P4 1.8ghz PC.

Whoooooosh! I can't get it to go any faster at the moment, if anyone knows a quicker way then let me know.

public static unsafe string ToBinary(uint val)
{
    sbyte* bin = stackalloc sbyte[32]; //32 bytes
    sbyte* index = bin; //duplicate the array pointer and use this as the iterator
    sbyte* stop = bin + 32; //stop after 32 bytes in the array

    uint mask = 0x80000000; //bit mask

    do
    {
        if((val & mask) != 0)
            *index =  (sbyte)0x31; 
        else
            *index =  (sbyte)0x30; 

        mask >>= 1;
    } while(++index != stop); //let the index catch up the buffer one and then stop

    index = bin; //reset pointer
    for(mask = 0; mask < 32 ; mask++)
        if(*(index++) == 0x31)
            break;

    return new string(bin, (int)mask, (int)(32 - mask));
}