Question

Find out how to populate the registers with appropriate parameters to swap the values 4 and 5 in the array arr. What are the instructions that will populate the general registers with the appropriate values?

arr:    .word     1,2,3,4,5

To populate r0:
To populate r1:
To populate r2:

Answer 1

You dint mention any specific assembaly language. So make concept cleare I used MIPS

t0,t1 and t2 gemnral purpose registers are used for r0,r1 and r2 respectively.

I run it on mars simulator. You can see the value by running step by step

if output is4554 means 45 before swapping and 54 after swaping

..........................cade..............................

.data
arr: .word 1,2,3,4,5
.text
addi $t0,$zero,12 # t0 represents r0 as array index t0=12 as 4 is at 4th possition
lw $t1,arr($t0)
#printing initial value of at location 4 you can think of arr[3]
lw $a0,arr($t0)
li $v0,1
syscall
addi $t0,$t0,4
lw $t2,arr($t0)# $t2 as r2
#printing initial value of at location 5 you can think of arr[4]
lw $a0,arr($t0)
li $v0,1
syscall
#swapping
sw $t1,arr($t0)
subi $t0,$t0,4
sw $t2,arr($t0)

#After swapping printing value
#printing initial value of at location 4 you can think of arr[3]
lw $a0,arr($t0)
li $v0,1
syscall
addi $t0,$t0,4
#printing initial value of at location 5 you can think of arr[4]
lw $a0,arr($t0)
li $v0,1
syscall

.........................end............................

........................output.............................

히 X CAUsersSantlal PrajapatiDesktopswapHomeworkLibasm-MARS 4.5 File Edit u Settings Tools Help - Run speed at max (no interaction Edit Execute Registers Coproc 1 Coproc 0 Name Number Value Text Segment Program Arguments: Bkpt Address at 268501008 Code Source 6W1 I Ox0040 00001 0x2008000c adda fe,40,12 0x00400004| 0x3c011001 luュ $1,4097 4: add! 두to, 두 zero, 12 + to represents ro as array index t0-12 аз 4 13 at 4th 331. x0040 0008| 0x002 eoe21 eddu $1,$1,68 x0040000e Ox8c290000 Iw 9,0(51) 0400010 0x3e011001 lui #1,409 Ox00400014| 0x002e0821 addu 41'41, f8 x00400018 0x8c240000 1v 4,0(1) 0x0040001c Ox24020001addau 두2,40,1 수a3 0x0 7 16 et2 8: 11 0,1 12 13 Data Segment Address 0x10010000 0x10010020 0x10010040 0x10010060 0x10010080 15 16 17 18 19 20 21 Value (+) Value (+4) Value (+8) Value (+C) value (-10) Value (+14) Value (-18) Value (+1c) 630 83 두35 636 657 Ox1001000 0x100100c0 0x100100e0 23 24 25 26 27 28 두t9 「 ナ 110x10010000(.data) -Id Hexadecimal Addresses □ Hexadecimal Values □ASCI 268468224 2147479548 Mars Messages Run IVO 5p 30 31 4554 4194452 Clear program 13 finished running (dropped off bottom) -- h1 Type here to search 9:59 AM 目da) 4/21/2018