Encoding:

Format:

DDIV rs, rt

Purpose:

Doubleword Divide

To divide 64-bit signed integers.

Description:

 (LO, HI) = GPR[rs] / GPR[rt]

The 64-bit doubleword in GPR rs is divided by the 64-bit doubleword in GPR rt, treating both operands as signed values. The 64-bit quotient is placed into special register LO and the 64-bit remainder is placed into special register HI.

No arithmetic exception occurs under any circumstances.

Restrictions:

If the divisor in GPR rt is zero, the arithmetic result value is UNPREDICTABLE.

Availability and Compatibility:

This instruction has been removed in Release 6.

Operation:

   LO = GPR[rs] div GPR[rt]
   HI = GPR[rs] mod GPR[rt]

Exceptions:

Reserved Instruction

Programming Notes:

See "Programming Notes" for the DIV instruction.

Historical Perspective:

In MIPS III, if either of the two instructions preceding the divide is an MFHI or MFLO, the result of the MFHI or

MFLO is UNPREDICTABLE. Reads of the HI or LO special register must be separated from subsequent instructions that write to them by two or more instructions. This restriction was removed in MIPS IV and MIPS32 and all subsequent levels of the architecture.