Question

Write an Assembly program that will multiply two arrays (index by index) and store the result in a third array. Declare an array: .data Arr1: .quad 10 #index 0 .quad 4 #index 1 Arr2: .quad 2,5,6.... Arr3: .quad 0,0,0.... To load array pointer address: Movq $Arr1, %rdx #stores address of Arr1 index 0 in rdx To move to the next index of an array: Adda $8,%rdx To retrieve data: Movg (%rdx), %rcx #will have data at address in rdx We can also use LEA instruction. Xorq %rbx,%rbx LEAQ (%rdx, %rbx,8), %<reg> #address if index 0 in reg Movq(%<reg>), %<reg> #data at index 0 Inc %rbx To store data: Movq %<reg>, (%<reg that has address>) .global main .text main: movq Sarr, %rcx movg (%rcx), %rax add $8,%rcx mova (%rcx), %rax #load address of index 0 #retrieve data at index 0 #go to next index 8 bytes over #get data at index 1 #or xorq %rcx,%rcx movq $arr, %rbx leaq (%rbx,%rcx,8), %rax #ADDRESS OF INDEX O movq (%rax),%rax #content at index 0 incq %rcx leaq (%rbx,%rcx,8), %rax #address of index 1 # or xorq %rcx, %rcx movq arr(%rcx,8), %rax #move content at index 0 to rax #or xor %rcx,%rcx movq Sarr,%rbx mova (%rbx,%rcx,8), %rdx #move content at index 0 # exiting mova $60,%rax # sys_exit syscall number: 60 xorq %Rdi, %Rdi # set exit status to O syscall

Answer 1

Assembly Language Program that will multiply two array ( index by index ) and store the result into third array

//Every step is explained in the comment of every line
 


ORIG X3000 MAIN AND R1, R1, #0 ; LOOP counter LOOP LD RZ, LIMIT ADD R2, R2, R1 BRZ END_LOOP ; Check to see if we've hit our limit LEA R2, arri ADD RZ, RZ, R1 LDR R3, R2, #0 ; Load the memory Location of arri ; Add our array index to get our current arri memory location ; Load the value at arr1[R1] into R3 LEA R2, arr2 ADD RZ, RZ, R1 LDR R4, R2, #0 ; Load the memory location of arr2 ; Add our array index to get our current arr2 memory location Load the value at arr2[R1] into R4 ; This loop is used to multiply our numbers ; R3 becomes our LOOPZ counter for the multiplication ; Example: 7 x 5 = 7 + 7 + 7 + 7 +7 AND R5, R5, #0 ADD R5, R5, R4 ADD R3, R3, #-1 LOOPZ ADD R5, RS, R4 Make R5 = R4 ; Reduce our count by 1 ADD R3, R3, #-1 BRZ END_LZ BR LOOPZ END_LZ ; Add our second number to itself ; Decrease our loop counter If our LOOPZ counter has reached then break LEA R2, arr3 ADD RZ, RZ, R1 STR R5, RZ, #0 ; Load the memory location of arr3 ; Add our array index to get our current arr3 memory location Store our answer currently in R5 into the memory location stored in RZ ADD R1, R1, #1 BR LOOP END_LOOP ; Increment our loop counter ; Branch to LOOP HALT Variables LIMIT FILL XFFFC ; Store the value of -4 into our loop limit variable 5 arri .FILL .FILL 2 .FILL 7 .FILL 3

7 arr2 .FILL .FILL 4 .FILL 1 .FILL 2 1 arr3 BLKW 4 ; used to store our answer . END

PS: Feel Free to ask any doubts in the comment section and don't forget to rate the answer