At the abstraction layer, everything is the same, at least we hope so. At the low level you will have to re-write it. You should NEVER include anything from the avr libraries i.e. #include <avr/io.h> for any project that does not use an AVR chip. From now on, you should be doing this:
/* For AVR */
#if defined(__AVR__)
#include <avr/io.h>
#endif
/* For PIC32 */
#if defined(__PIC32MX__)
#include <p32xxxx.h> /* this gives all the CPU/hardware definitions */
#include <plib.h> /* this gives the i/o definitions */
#endif
There are also a few predefined macros which may be useful as arguments
Read more -->