void silk_NLSF_stabilize(
          opus_int16            *NLSF_Q15, /* I/O   Unstable/stabilized normalized LSF vector in Q15 [L]       */
 const opus_int16            *NDeltaMin_Q15, /* I     Min distance vector, NDeltaMin_Q15[L] must be >= 1 [L+1]   */
 const opus_int              L                   /* I     Number of NLSF parameters in the input vector              */
)
{
    opus_int   i, I=0, k, loops;
    opus_int16 center_freq_Q15;
    opus_int32 diff_Q15, min_diff_Q15, min_center_Q15, max_center_Q15;

 /* This is necessary to ensure an output within range of a opus_int16 */
    silk_assert( NDeltaMin_Q15[L] >= 1 );

 for( loops = 0; loops < MAX_LOOPS; loops++ ) {
 /**************************/
 /* Find smallest distance */
 /**************************/
 /* First element */
        min_diff_Q15 = NLSF_Q15[0] - NDeltaMin_Q15[0];
        I = 0;
 /* Middle elements */
 for( i = 1; i <= L-1; i++ ) {
            diff_Q15 = NLSF_Q15[i] - ( NLSF_Q15[i-1] + NDeltaMin_Q15[i] );
 if( diff_Q15 < min_diff_Q15 ) {
                min_diff_Q15 = diff_Q15;
                I = i;
 }
 }
 /* Last element */
        diff_Q15 = ( 1 << 15 ) - ( NLSF_Q15[L-1] + NDeltaMin_Q15[L] );
 if( diff_Q15 < min_diff_Q15 ) {
            min_diff_Q15 = diff_Q15;
            I = L;
 }

 /***************************************************/
 /* Now check if the smallest distance non-negative */
 /***************************************************/
 if( min_diff_Q15 >= 0 ) {
 return;
 }

 if( I == 0 ) {
 /* Move away from lower limit */
            NLSF_Q15[0] = NDeltaMin_Q15[0];

 } else if( I == L) {
 /* Move away from higher limit */
            NLSF_Q15[L-1] = ( 1 << 15 ) - NDeltaMin_Q15[L];

 } else {
 /* Find the lower extreme for the location of the current center frequency */
            min_center_Q15 = 0;
 for( k = 0; k < I; k++ ) {
                min_center_Q15 += NDeltaMin_Q15[k];
 }
            min_center_Q15 += silk_RSHIFT( NDeltaMin_Q15[I], 1 );

 /* Find the upper extreme for the location of the current center frequency */
            max_center_Q15 = 1 << 15;
 for( k = L; k > I; k-- ) {
                max_center_Q15 -= NDeltaMin_Q15[k];
 }
            max_center_Q15 -= silk_RSHIFT( NDeltaMin_Q15[I], 1 );

 /* Move apart, sorted by value, keeping the same center frequency */
            center_freq_Q15 = (opus_int16)silk_LIMIT_32( silk_RSHIFT_ROUND( (opus_int32)NLSF_Q15[I-1] + (opus_int32)NLSF_Q15[I], 1 ),
                min_center_Q15, max_center_Q15 );
            NLSF_Q15[I-1] = center_freq_Q15 - silk_RSHIFT( NDeltaMin_Q15[I], 1 );
            NLSF_Q15[I] = NLSF_Q15[I-1] + NDeltaMin_Q15[I];
 }
 }

 /* Safe and simple fall back method, which is less ideal than the above */
 if( loops == MAX_LOOPS )
 {
 /* Insertion sort (fast for already almost sorted arrays):   */
 /* Best case:  O(n)   for an already sorted array            */
 /* Worst case: O(n^2) for an inversely sorted array          */
        silk_insertion_sort_increasing_all_values_int16( &NLSF_Q15[0], L );

 /* First NLSF should be no less than NDeltaMin[0] */
        NLSF_Q15[0] = silk_max_int( NLSF_Q15[0], NDeltaMin_Q15[0] );

 
         /* Keep delta_min distance between the NLSFs */
         for( i = 1; i < L; i++ )
            NLSF_Q15[i] = silk_max_int( NLSF_Q15[i], NLSF_Q15[i-1] + NDeltaMin_Q15[i] );
 
         /* Last NLSF should be no higher than 1 - NDeltaMin[L] */
         NLSF_Q15[L-1] = silk_min_int( NLSF_Q15[L-1], (1<<15) - NDeltaMin_Q15[L] );

 /* Keep NDeltaMin distance between the NLSFs */
 for( i = L-2; i >= 0; i-- )
            NLSF_Q15[i] = silk_min_int( NLSF_Q15[i], NLSF_Q15[i+1] - NDeltaMin_Q15[i+1] );
 }
}

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.