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Re: Tree-SSA self checking infrastructure
> In message <20031119190649.GQ16923@atrey.karlin.mff.cuni.cz>, Jan Hubicka write
> s:
> >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
I replace tail call by edge back to the beggining of function and I
possibly split edge fron entry point. I also take care to construct PHI
nodes for all referenced arguments by hand.
This does change CFG, but does not change dominance relationships.
I am however removing call and perhaps we are maintaining something that
relies on the presence of call...
Honza
> are the key questions.
>
> >> The exception is the dominator based jump threader where we do rerewrite
> >> existing SSA_NAMEs. In that case we know there are no overlaps as we have
> >> done no optimizations which could have created an overlap.
> >
> >I see. It would be nice to drop a comment somewhere in tree-optimize.c
> >clarifying what can be renamed when.
> Err, I thought there was a comment regarding this issue in the code.
> Regardless, from discussions with Andrew we may have the ability to
> un-ssa specific variables, which would make this a non-issue.
> jeff