Not all instructions are re-startable. ldm/stm that writes back to the base register is only re-startable if the write-back and the update to PC are last. The

Not all instructions are re-startable. ldm/stm that writes back to the base register is only re-startable if the write-back and the update to PC are last. The microcontroller-scale cores have a few extra bits in the control/status register that govern restart of an interrupted ldm/stm or IT (if-then, a form of hammock predication).