n the following ARM$9$ program, there are two examples of $$data

forwarding$$ and one further example of a $$read$-$after$-$write$$ hazard that

results in an interlock. Identify all three.

Mnemonic Comment

MOV r$1,$ #$0$x$0004$A$000$ ; move $0$x$0004$A$000$ into r$1$

MOV r$2,$ #$0$x$00003$BC$0$ ; move $0$x$00003$BC$0$ into r$2$

MOV r$0,$ r$1,$ LSL #$4$ ; left shift r$1$ by $4$ bits

SUB r$3,$ r$2,$ r$1$ ; subtract r$1$ from r$2$

ADD r$4,$ r$1,$ r$2$ ; add r$1$ and r$2,$ sum in r$4$

RSB r$5,$ r$4,$ r$0$ ; subtract r$4$ from r$0$

MOV r$6,$ #$0$x$000002$E$4$ ; move $0$x$000002$E$4$ into r$6$

MOV r$7,$ #$0$x$0002$E$400$ ; move $0$x$0002$E$400$ into r$7$

ADD r$2,$ r$1,$ r$0$ ; add r$1$ and r$0,$ sum in r$2$