https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101639
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Blocks| |53947
Last reconfirmed| |2021-07-27
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
vectorizable_reduction fails the
6692 scalar_dest = gimple_assign_lhs (stmt);
6693 scalar_type = TREE_TYPE (scalar_dest);
6694 if (!POINTER_TYPE_P (scalar_type) && !INTEGRAL_TYPE_P (scalar_type)
6695 && !SCALAR_FLOAT_TYPE_P (scalar_type))
6696 return false;
6697
6698 /* Do not try to vectorize bit-precision reductions. */
6699 if (!type_has_mode_precision_p (scalar_type))
6700 return false;
check. I guess we could relax that for BIT_*_EXPR reductions. But then
we run into
t5.c:4:21: note: vect_is_simple_use: vectype vector(16) unsigned char
t5.c:4:21: missed: mixed mask and nonmask vector types
t5.c:1:6: missed: not vectorized: relevant stmt not supported: _7 = _4 &
r_14;
t5.c:4:21: missed: bad operation or unsupported loop bound.
I guess that's mainly a fault of missed bool pattern handling of the
reduction - we fail to make p[i] != 0 available as non-boolean vector.
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53947
[Bug 53947] [meta-bug] vectorizer missed-optimizations
