https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61338
--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> ---
Possibly easier is the case of a reduction, where permutations are clearly
irrelevant.
int f(int*arr,int size){
int sum=0;
for(int i = 0; i < size; i++){
sum += arr[size-1-i];
}
return sum;
}
We still have a VEC_PERM_EXPR in the hot loop before accumulating.
(by the way, we accumulate in a variable of type "vector(4) int", while I would
expect "vector(4) unsigned int" for overflow reasons)
