SAR : Shift Arithmetic Right (divide signed by a power of two)

The bits of the source register (snd) are shifted towards the LSB, by a number of bits indicated by either

• a 4-bit immediate value (short immediate or extended immediate forms)
• the other register (si4) (short register or extended register forms)
• a 16-bit value (long immediate form).

The MSBs of the result are filled with the original sign bit, while the logic shift (SHR) fills the MSB with 0s.