loop-vec-pseudo.cpp

// The vectorizer can determine the best vector width, but let's consider vectorize_width(4)
#pragma clang loop vectorize(enable) vectorize_width(4)
int addScalar(int *x, int n, int s) {
  for (int i = 0; i < n/4/*vector_width*/; ++i)
    // The pseudo code bellow would be performed as a single SIMD vector instruction.
    x[i] += s;
    x[i + 1] += s;
    x[i + 2] += s;
    x[i + 3] += s;
}