https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98813
--- Comment #2 from Jiu Fu Guo <guojiufu at gcc dot gnu.org> --- For code: for (unsigned int k = 0; k < BS; k++) { s += A[k] * B[k]; } PR48052 handles this, and for this code, the additional runtime check seems not required. If there is offset in code: for (unsigned int k = 0; k < BS; k++) { s += A[k+3] * B[k+3]; } This code is not vectorized then.