RSSA

[Stephen Weeks]

> I started looking at some of the changes.  One question: are you
> going to make array inialization explicit in RSSA (and/or Machine)?

Yes, but it's not there right now.

> If you don't, then we need the live variables at an array allocation
> to fill in the live variables that are live around the
> initialization loop.

Arrays are always at the beginning of a basic block, so until it's
there (add it if you want (or I will)), you can use the live of the
block.

> If you do, bear in mind that that will be a new loop where a signal
> limit check will be inserted.

No.  This is one loop that can't have a signal limit check -- a
pointer array must be completely filled in or the gc will not be able
to trace it.