shrinker checked in (fwd)

[Matthew Fluet]

Did this reach you guys?  I got a weird undeliverable message.

---------- Forwarded message ----------
Date: Wed, 14 Nov 2001 16:19:55 -0500 (EST)
From: Matthew Fluet <fluet@snoball.cs.cornell.edu>
To: MLton@sourcelight.com
Subject: Re: shrinker checked in


> > Here are the results comparing the 20011006 release and the internal
> > versions with ssa and cps optimization.  Compile times for the
> > internal version are of course horrible, because it is the NJ compiled
> > version.   The runtime ratios are all fine except for knuth-bendix.
> 
> Well, it looks like something is leaving around excess allocations; also,
> almost twice the stack size.

Playing around with mlprof, I think there is at least one problem with the
flattener.  Check out tryrec_0 and rew_loop_0 under CPS and SSA
optimizations.

More clues: in CPS, the Failure exception carries string, while in SSA it
carries (string, unit ref).  So, something in useless (that's the only
pass that might figure out that the unit ref is the same everywhere?).