Function findLastSet [src]

Finds the index of the last set bit. If no bits are set, returns null.

Prototype

pub fn findLastSet(self: Self) ?usize

Parameters

self: Self

Source

  pub fn findLastSet(self: Self) ?usize {
    if (self.bit_length == 0) return null;
    const bs = @bitSizeOf(MaskInt);
    var len = self.bit_length / bs;
    if (self.bit_length % bs != 0) len += 1;
    var offset: usize = len * bs;
    var idx: usize = len - 1;
    while (self.masks[idx] == 0) : (idx -= 1) {
        offset -= bs;
        if (idx == 0) return null;
    }
    offset -= @clz(self.masks[idx]);
    offset -= 1;
    return offset;
}  