Use the smallest data type possible to decrease the size and increase the speed of an FPGA VI. For example, the Index Array function uses a 32-bit integer as the default for the first index input. If the array you wire to this input contains less than 256 elements, you can change the representation of the input from a 32-bit integer to an 8-bit integer.
The Multiply function coerces inputs to a larger data type. For example, if you wire a 16-bit and a 32-bit integer to the inputs of the Multiply function, the function coerces the 16-bit integer into a 32-bit integer. If you want to avoid coercion to a larger data type, use the Saturation Multiply VI instead.
If you use the Loop Timer, Tick Count, or Wait VI, you can save space on the FPGA by using the smallest Size of Internal Counter possible for the FPGA VI.