https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102512
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |rguenth at gcc dot gnu.org
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
max_9 = *p_8(D);
_10 = {max_9, max_9, max_9, max_9, max_9, max_9, max_9, max_9};
vect__4.7_13 = MEM <vector(8) short int> [(short int *)p_8(D)];
vect_max_11.8_14 = MAX_EXPR <_10, vect__4.7_13>;
_20 = .REDUC_MAX (vect_max_11.8_14); [tail call]
it's a bit difficult to improve here - match.pd doesn't like MEMs too much
and this all just collapses because _10 is a splat of element zero of
vect__4.7_13 ...
In theory the vectorizer could use the first full vector as initial value
or of course a vector of all SHORT_MIN. But the intent of using the first
scalar value was that this would optimize better ...
