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Re: [PATCH, PR68976] Use reaching def phi arg in sese_add_exit_phis_edge


On Fri, Jan 15, 2016 at 7:58 AM, Tom de Vries <Tom_deVries@mentor.com> wrote:
> During scop detection/canonicalize_loop_closed_ssa_form, an exit phi is
> introduced in the loop for _24:
> ...
>   <bb 21>:
>   # _58 = PHI <_24(22)>
> ...
> Note that _24 is not defined in the loop, but before it. AFAIU the header
> comment of canonicalize_loop_closed_ssa_form, this phi is not needed. That
> might be the root cause of the bug,

I think that may be the problem, as it is invariant in the loops, so
it is considered to be a parameter of the scop.
Let me see if we could avoid adding that phi node in the first place.


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