Question $6-$ Interrupt handling gone wrong $(8$ pts$)$

In class, we have discussed the ultimate ISR as an homage to Claude Shannon's ultimate machine: The ultimate ISR does nothing except clearing the interrupt flag. Below is an ultimate ISR that serves push buttons S$1$ and S$2.$ You can assume that the IVT has been correctly populated.

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Ultimate$\_$ISR:

check$\_$S$1$: ; Confirm the source of the interrupt

bit.b #BIT$1,$ &P$1$IFG

jnc check$\_$S$2$

; Do nothing, just clear the interrupt flag for S$1$

bic.b #BIT$1,$ &P$1$IFG

check$\_$S$2$: ; Confirm the source of the interrupt

bit.b #BIT$2,$ &P$1$IFG

jnc ret$\_$from$\_$ISR

; Do nothing, just clear the interrupt flag for S$2$

bic.b #BIT$2,$ &P$1$IFG

ret$\_$from$\_$ISR:

ret

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What will happen when you press push button S$2?$

Give a short but precise answer that explains what happens at the register level. This will be text entry in Carmen. One sentence suffices.