No, I don't think they did. I think they're just taking their old awful unmaintainable source, adding more to the hot heap of slag, and then using some clever compiler optimizations to make it run better. No love for the actual programmers. You get to keep working on the nightmare code (3 months to make changes...).
Now, color me impressed if the thing output the same language as the original source, all spruced up.
As it is, they'll just have a code base that will eventually transform into the anti-christ cause management will always be like, "Hey, don't ever fix the code, just run that see-saw whatever thing on it afterwards."