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# `__uadd8` intrinsic

This intrinsic inserts a `UADD8` instruction into the instruction stream generated by the compiler. It enables you to perform four unsigned 8-bit integer additions.

The GE bits in the APSR are set according to the results.

```unsigned int __uadd8(unsigned int `val1`, unsigned int `val2`)
```

Where:

`val1`

holds the first four 8-bit summands for each addition

`val2`

holds the second four 8-bit summands for each addition.

The `__uadd8` intrinsic returns:

• the addition of the first bytes in each operand, in the first byte of the return value

• the addition of the second bytes in each operand, in the second byte of the return value

• the addition of the third bytes in each operand, in the third byte of the return value

• the addition of the fourth bytes in each operand, in the fourth byte of the return value.

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:

• if `res`[7:0] ≥ 0x100 then APSR.GE[0] = 1 else 0

• if `res`[15:8] ≥ 0x100 then APSR.GE[1] = 1 else 0

• if `res`[23:16] ≥ 0x100 then APSR.GE[2] = 1 else 0

• if `res`[31:24] ≥ 0x100 then APSR.GE[3] = 1 else 0.

Example:

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

res = __uadd8(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;
}
```