Re: [tree-ssa] must-alias analysis

[Geoff Keating <geoffk at geoffk dot org>]

law@redhat.com writes:

> In message <1058187784.4973.106.camel@frodo.toronto.redhat.com>, Diego Novillo 
> writes:
>  >     4. The must-alias pass will then scan the program looking for
>  >        variables whose address is not needed anymore.  Those that match
>  >        are removed from alias lists and are renamed into SSA as regular
>  >        non-addressable variables.  This exposes the variables to all
>  >        the usual optimizations.
> Cool.  Do we make sure and clear TREE_ADDRESSABLE on these variables?
> 
> I _think_ that's the only missing step to get you to a point where you
> never have to worry about put_var_into_stack and fixup_var_refs!   ie,
> for a given automatic variable, we know before expanding into RTL whether
> or not the variable is going to need a stack slot or not.

Hey, does this mean we can finally start ignoring 'register' at -O1
and higher except for syntax checking?

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