Re: Tree-SSA self checking infrastructure

[Jan Hubicka <hubicka at ucw dot cz>]

> In message <20031119210127.GB31811@redhat.com>, Richard Henderson writes:
>  >On Wed, Nov 19, 2003 at 12:13:06PM -0700, law@redhat.com wrote:
>  >>  >This brings me into questions about my tail call updating code.
>  >>  >Perhaps I need to re-do SSA form on call cobbered variables after
>  >>  >removing the call?
>  >> Are you changing the CFG?  Are you changing the dominator tree?  Those
>  >> are the key questions.
>  >
>  >Yes, he is, but only by adding a new block on the ENTRY->BB0 edge,
>  >and then edges into that block from the tail recursion sites.
> So that would mean he needs PHIs for any arguments that are changed which
> reach the loop backedge and for local variables in the toplevel scope
> which have a definition which reaches the backedge.

I am doing the first, how can I implement the second? That may be
actually one problems I am seeing...
(given the fact that only the tail recursion ellimination run as very
last pass before de-ssa breaks I think it is actually not the case, but
definitly needs to be done right)

Honza
> 
> 
> 
> 
>  > I may be mistaken, but I thought the new phi nodes he was adding 
>  > there would be correct.  Perhaps this is a good test for a verify_ssa
>  > pass?
> Definitely a good test.
> jeff