How to reduce re-compilation time in Quartus pro ?

There are many techniques to save compile time. Obviously, use a "beefy" machine for compilations (multiple cores, lots of RAM) and make sure the parallel compilation feature is enabled in Quartus.

Getting to design-specific ways of reducing compile time, block-based design techniques can potentially reduce compile time:

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/ug/ug-qpp-block-based-design.pdf

And that includes the new fast preservation feature:

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/an/an899.pdf

Also search for "rapid recompile".

There are training classes available for these as well:

Reducing Compile Time with Fast Preservation

Incremental Block-Based Compilation in the Intel Quartus® Prime Pro Software: Introduction

Finally, you can use Fitter snapshots to compile up to a particular stage of the Fitter to save time (referred to as incremental optimization), but if you need to test this in hardware, that won't be as useful:

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/ug/ug-qpp-compiler.pdf

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