Question

write an 8086 assembly program that 1) adds two operand. 2) that adds operands until the new value to be added is 0. 3) Write a program that increments by 2 the content of a register 10 times.

Answer 1

8086 assembly program that

1) adds two operand.

main:

push rbp

mov rbp, rsp

mov DWORD PTR [rbp-4], 0

mov DWORD PTR [rbp-8], 6

mov DWORD PTR [rbp-12], 5

mov edx, DWORD PTR [rbp-8]

mov eax, DWORD PTR [rbp-12]

add eax, edx

mov DWORD PTR [rbp-4], eax

mov eax, 0

pop rbp

ret

2) that adds operands until the new value to be added is 0.

.LC0:

.string "%d"

main:

push rbp

mov rbp, rsp

sub rsp, 16

mov DWORD PTR [rbp-4], 0

mov DWORD PTR [rbp-8], 0

.L3:

lea rax, [rbp-8]

mov rsi, rax

mov edi, OFFSET FLAT:.LC0

mov eax, 0

call scanf

mov eax, DWORD PTR [rbp-8]

add DWORD PTR [rbp-4], eax

mov eax, DWORD PTR [rbp-8]

test eax, eax

je .L2

jmp .L3

.L2:

mov eax, 0

leave

ret

3) Write a program that increments by 2 the content of a register 10 times.

.LC0:

.string "Increment by 2 "

main:

push rbp

mov rbp, rsp

sub rsp, 16

mov DWORD PTR [rbp-8], 20

.L3:

cmp DWORD PTR [rbp-8], 0

je .L2

add DWORD PTR [rbp-4], 2

jmp .L3

.L2:

mov edi, OFFSET FLAT:.LC0

mov eax, 0

call printf

mov eax, 0

leave

ret