On the optimization of large slice

I see that when I convert the slice into a byte array, I traverse it. If you can judge the slice length here, when the slice length is too large, consider using other conversion methods.

for example:
arr is a big slice.
arr := make([]float32,1000)
header := *(*reflect.SliceHeader)(unsafe.Pointer(&arr))
header.Len = len(arr) * 4
header.Cap = header.Len
bytes := ([]byte)(unsafe.Pointer(&header))