The fp IDE uses its own internal compiler, not the installed command-line one, so it doesn't matter whether you install a cross-compiler.Yes that can be done. I am actually always using it both on Linux 64 and Windows 10 64.
If anything, you may try building a 64-bit IDE with it, but note that I'm not sure if it can be done. It it can be, it would be nice if you told us ;D
Best of lucks.