Disable unrolling

The trip count %trip_count% after loop unrolling is too small compared to the vector length %vl% . To fix: Prevent loop unrolling or decrease the unroll factor using a directive: !DIR$ NOUNROLL or !DIR$ UNROLL.

Example

Disable automatic loop unrolling using !DIR$ NOUNROLL
!DIR$ NOUNROLL
do i = 1, m
    b(i) = a(i) + 1
    d(i) = c(i) + 1
enddo

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