The European Space Agency uses a radiation tolerant microprocessor for most of its applications. This is a generic processor, my project was to add some specific capabilities optimized for a very specific task (receiving satellite signals)
A generic microprocessor can do most operations, but not in a very efficient way. For complex operations that need to be done over and over, it may be a good idea to add specific hardware to do it faster inside the microprocessor.
In my case I added some custom operations for decoding satellite signals up to 16 times faster. This was done by using parallelism techniques and Very Long Instruction Word (VLIW) paradigms.