Encoding:

Format:

DADDIU rt, rs, immediate

Purpose:

Doubleword Add Immediate Unsigned

To add a constant to a 64-bit integer

Description:

 GPR[rt] = GPR[rs] + sign_extend(immediate)

The 16-bit signed immediate is added to the 64-bit value in GPR rs and the 64-bit arithmetic result is placed into

GPR rt.

No Integer Overflow exception occurs under any circumstances.

Restrictions:

Operation:

GPR[rt] = GPR[rs] + sign_extend(immediate)

Exceptions:

Reserved Instruction

Programming Notes:

The term "unsigned" in the instruction name is a misnomer; this operation is 64-bit modulo arithmetic that does not trap on overflow. It is appropriate for unsigned arithmetic such as address arithmetic, or integer arithmetic environments that ignore overflow, such as C language arithmetic.