Clojurians Log v2

I've a question about the vector-linear-frac function in CUDA, please. I see that when the scaleb is 0 and shiftb is 1.0, then the CUDA function that gets called is vector_scale_shift. This function gets called with the in and out buffers, along with their respective offsets and strides, and also scalea, shifta, scaleb, and shiftb. My question is about the arguments of scaleb and shiftb. These arguments get sent to the kernel, but they're not used at all. I thought that maybe they were passed along as a part of a common pattern, but the parameters are set up exclusively for this function. Is there some reason to keep them there?