[PATCH 2/2] CmmOpt cannot assume single assignment for hand-written or new codegen Cmm.

[Edward Z. Yang]

Excerpts from Simon Marlow's message of Tue Apr 05 04:31:56 -0400 2011:
> > +   -- XXX The above is not actually true: hand-written Cmm and Cmm from
> > +   -- the new code generator are not single-assignment.  So we do an
> > +   -- extra check to make sure that the register being changed is not
> > +   -- one we were relying on.  I don't know how much of a performance
> > +   -- hit this is; if it's a big problem we may want to make a set of
> > +   -- used registers and match against that. -- EZY
> 
> It looks from the patch like you already made a register set to optimise 
> this.  Is the comment out of date?

Oh yes, that's out of date. I'll fix that.

Edward