This intrinsic inserts a UQSUB8 instruction into the instruction stream generated by the compiler. It enables you to perform four unsigned 8-bit integer subtractions, saturating the results to the 8-bit unsigned integer range 0 ≤ x ≤ 2⁸ - 1.

unsigned int __uqsub8(unsigned int val1, unsigned int val2)

where:

The __uqsub8 intrinsic returns:

The results are saturated to the 8-bit unsigned integer range 0 ≤ x ≤ 2⁸ - 1.

Example:

unsigned int subtract_bytes(unsigned int val1, unsigned int val2)
{
  unsigned int res;

    res = __uqsub8(val1,val2); /* res[7:0] = val1[7:0] - val2[7:0]
                                  res[15:8] = val1[15:8] - val2[15:8]
                                  res[23:16] = val1[23:16] - val2[23:16]
                                  res[31:24] = val1[31:24] - val2[31:24]
                               */
    return res;
}