https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108639
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |amacleod at redhat dot com
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The problem is in
271 if (relation_equiv_p (rel) && lh == rh)
We see
# RANGE [irange] int [0, 1] NONZERO 0x1
# iftmp.0_6 = PHI <_10(3), 0(2)>
# RANGE [irange] long int [0, 1] NONZERO 0x1
_3 = (long int) iftmp.0_6;
# RANGE [irange] unsigned int [0, 1] NONZERO 0x1
_4 = (unsigned int) iftmp.0_6;
# RANGE [irange] long int [-INF, +INF] NONZERO 0x3
_5 = _3 << _4;
so lhs and rhs indeed have the same range, but unlike most binary operations,
shifts/rotates have the same type between lhs and rhs1, but rhs2 can have
different type.
So, the lh == rh comparison ICEs because the wide_ints have different precision
(but same values).
