Re: I found a FORTH stack optimzer, but could use a better version.

foxchip wrote:
> Simple peephole optimizers are often used
> to patch badly generated code this way.

The quite simple peephole optimizer I've implemented in bigFORTH nearly 20
years ago wasn't there to improve badly code; most patterns I've put in
were there to improve good code. But it is a peephole optimizer on the
machine code level (68k and later x86 machine code). The intention was to
be simple (the rule interpreter is two screens, the rules themselves take
a
line each), fast and reversible. SEE can undo most of the optimizations to
figure out what kind of source code might have generated the machine code.

Today, a real native code compiler can be a factor 1.5-2 faster for good
code, and a factor 5-10 for bad code. I've started a real native code
compiler for my 4stack processor (quite different target), and I'm
planning
to implement one with similar algorithms for x86_64, where the additional
registers increase the benefit vs. the peephole optimizer. As time
permits,
for sure.

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
http://www.jwdt.com/~paysan/