df.c and cond_exec question

[Steven Bosscher]

On Thursday 23 September 2004 01:58, Steve Ellcey wrote:
> I want to look into adding code to df_analyze to handle cond_exec but I
> thought I would send an email first and make sure that df.c isn't
> something that is going to become obsolete soon due to the SSA work or
> that there isn't some other reason why handling cond_exec instructions
> in df_analyze is a bad idea or impractical.  I see uses of df_analyze in
> loop-invariant.c, modulo-sched.c, ra.c, and web.c so I don't think it
> is going away soon.

I was actually hoping we can use df.c in more passes.  Right now we
have many passes with their own little data flow analyzer.  Sharing
one df module among all passes is a *good* thing.  For example, you
would add cond_exec support and all passes using it would know about
it.

Unfortunately, cond_execs are not generated until after reload, that
probably means that all passes before reload (and reload itself?) do
not understand them...

Gr.
Steven