__sadd8 intrinsic

This intrinsic inserts an SADD8 instruction into the instruction stream generated by the compiler. It enables you to perform four 8-bit signed integer additions. The GE bits in the APSR are set according to the results of the additions.

unsigned int __sadd8(unsigned int val1, unsigned int val2)

Where:

val1

holds the first four 8-bit summands

val2

holds the second four 8-bit summands.

The __sadd8 intrinsic returns:

Each bit in APSR.GE is set or cleared for each byte in the return value, depending on the results of the operation. If res is the return value, then:

Example:

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

    res = __sadd16(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;
}
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