cpplib: Separate out translation phases 1 and 2

[Neil Booth]

Neil Booth wrote:-

> Actually, WTF, I think I'll do this, though like I said it's not really
> a fair comparison.  I'll report the results tomorrow to "make bootstrap"
> GCC before and after the patch with --enable-languages=c and
> --disable-checking; the latter setting will also magnify any slowdown.

After:

real	31m32.023s
user	28m36.130s
sys	1m52.130s

Before:

real	30m55.332s
user	28m18.960s
sys	1m48.990s

Which is 2% slowdown.  Since the new code doesn't take advantage of
newly available optimizations, and also has baggage from the old way of
doing things, it can only get better and I don't consider this a blocker.
If you like I'll keep the current tree around and I'll run the test
again in a week or so.  I'm still waiting for your alternative multibyte
implementation suggestions...

Neil.