reg_known_value and copying collection

[Geoff Keating]

> Date: Fri, 13 Dec 2002 13:38:37 -0500 (EST)
> From: Daniel Berlin <dberlin@dberlin.org>

> The more variables you make GC'd, the less places this might matter.
> The more we don't apply a moving gcc, the more fragmentation and worse
> locality gets.
> 
> So ideally, I want to do both.

Remember, there is a cost to having more variables GCed, and a cost to
compacting memory.  The most efficient solution might not be to GC
every variable and compact memory every time.

The cost of GCing a single small structure is not noticeable; but a
large array with many pointers is more expensive, and lots of little
structures is expensive.

-- 
- Geoffrey Keating <geoffk@geoffk.org>