Articles from The Big E-UAE JIT blog

Address Unknown

Finally all the normal addressing modes are done in this update. As I mentioned in the previous post: the final missing pieces were the 68020 (complex) addressing modes.
This took me lot longer than I expected. Not just because these addressing modes are complicated, but also because memory reading is involved.

Apple from the Tree

I try to keep this post short. New update is available:

  • MacOSX Darwin PowerPC support is implemented.
  • Fixed address distance calculation for the PowerPC native relative branch instructions.
  • Refactored the boolean values to use TRUE/FALSE preprocessor defines.

Big thanks goes to Tobias Netzel, who implemented the MacOSX support for the JIT compiling and helped me chasing down one more sneaky bug.

Bug! *Splat*

Every developer knows the feeling when finally he/she finds a bug and slaps to the forehead while mumbling: "How on earth was this thing ever been working?..."

Well, it just happened to me, I have fixed a bug that stopped the ROM from booting. It was a rather stupid mistake (as usually); for the details check out the update.
In this other minor update I have fixed one more nuance with the wrong addresses in the dumped PowerPC code log.

Optimize It

I am back from the holidays for sometime now, but I got swamped instantly by the work in my daytime job. I had very little energy on the project in the nights, which was spent on two things: chasing that #@!% bug which is killing me and implementing the data-flow optimization.


After a long-long time we are going to go on holiday with my beloved wife.

While I am AFK (pick one) please just sit patient and try to find the bug that prevents the OS from booting, will ya?

Thanks. :)

See ya in August.

God Save the Queen

Thank you dear Queen Elizabeth II that Your Majesty has birthday, just like us, puny humans do. Even if it is not on this day yet we got a day off to celebrate in New Zealand too. (Well, logic is not a strong point of human society.)

So, I decided to celebrate Her Majesty's birthday by doing some coding.

The update is a little bit short and not too interesting, just a couple more instructions implemented: