https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110131
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #4)
> So I have a VRP patch which gets us to:
/* If the value range is defined by more than one pair,
try to optimize to a singularity if either
the first or last pair is a singleton. */
That is if we have:
a range like: [0, 0][3, 32768][4294934529, +INF]
and we the comparison like `_37 <= 2`
Since 2 is a value between the first 2 pairs, we can just say this should be
the same as `_37 == 0` because that is the only value that is valid here.
The same idea happens for the last 2 pairs (and the last pair is a singleton).
Also if we only 2 pairs prefer the one which is 0 (since 0 is always simplier).
