I had spent lot of time on understanding and reshaping the x86 JIT compiling, and fit the PPC code emitter into it. No, no and no. The source code is so deeply convoluted, riddled with residue from debugging, useless functions and scary/cryptic workarounds that I had to give it up.
So, I finally decided: I will rip the x86 part out of the recent E-UAE sources. The PPC code emitter will come as a brand new part, won't depend on the x86 counterpart.