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$1$: What does the following code do$?$ Feel free to test random numbers on the two registers.

xor x$1,$ x$1,$ x$2$

xor x$2,$ x$1,$ x$2$

xor x$1,$ x$1,$ x$2$

Q$1\mathrm{.}1$:

$($a$)$

Sets x$1$ to $0$

$($b$)$

Sets x$1$ to ~$($x$1^$ x$2),$ and sets x$2$ to x$1^$ x$2$

$($c$)$

Sets x$2$ to $0$

$($d$)$

Sets x$1=$ x$2$

$($e$)$

Sets x$1$ to $-1$

$($f$)$

Sets x$1$ to x$1$ & x$2,$ and sets x$2$ to x$1|$ x$2$

$($g$)$

Sets x$2$ to $-1$

$($h$)$

Sets x$1$ to x$1^$ x$2,$ and sets x$2$ to ~$($x$1^$ x$2)$

$($i$)$

Swaps x$1$ and x$2$

$($j$)$

Sets x$1$ to x$1|$ x$2,$ and sets x$2$ to x$1$ & x$2$

$2$: After the following code is run, what is contained in x$12?$ Answer with $8$ digits of hexadecimal.

Hint: Note that RISC$-$V registers contain $32-$bit data. srai performs a sign$-$extended right shift.

li x$10,0$x$84$FF

slli x$12,$ x$10,0$x$10$

srai x$13,$ x$12,0$x$10$

srli x$14,$ x$12,0$x$08$

and x$12,$ x$13,$ x$14$

Q$2\mathrm{.}1$:

x$12=0$x

$3$: Given the following code sequence $($assume x$5$ is somewhere on the stack$)$:

addi x$11,$ x$0,-1261$

sw x$11,0($x$5)$

sh x$11,2($x$5)$

lb x$12,1($x$5)$

lbu x$13,2($x$5)$

What is the $32-$bit value stored in x$12$ and x$13?$ Answer with $8$ digits of hexadecimal.

Hint: RISC$-$V uses little endian. Take note of sign$-$extension when doing load instructions.

Q$3\mathrm{.}1$:

x$12=0$x

Q$3\mathrm{.}2$:

x$13=0$x