Flash Prom Size

Hi All:
I am in the process of development of code with some for controlling
some FPGA's, I am hitting a road block where the Flash Prom size is
smaller than the code size. Can anyone let me know if there are any
compression algorithms for compressing data into flash and decompress
when loading it into the FPGA's...

If there are any links I would appreciate if you could direct to them

Thanks in advance

.