Question

Implement the following C++ expression val1 = (val2 * val3) / (val4 − 3) in assembly language
using:
• 8-bit unsigned operands
• 16- bit unsigned operands
• 32-bit unsigned operands
a- Use the MASM assembler with .Data to initialize your variables, write your code in
the .code segment. Add comments explaining your code
b- Modify the code to prompt the user to enter the information -use 32-bit unsigned
operands only-, and show the output on the console, and dump your registers as
well using Irvine32 library
Copy, paste and save your code into a word document. Add a screen shot of the registers
before, during and at the end of the debugging mode.

Answer 1

NOTE :- MASM compiler :- x86-64 gcc (latest)

32-bit unsigned operands :-

mov edx, DWORD PTR val2[rip]

mov eax, DWORD PTR val3[rip]

imul eax, edx

mov edx, DWORD PTR val4[rip]

lea ecx, [rdx-3]

mov DWORD PTR [rbp-4], ecx

mov edx, 0

div DWORD PTR [rbp-4]

mov DWORD PTR val1[rip], eax

16-bit unsigned operands :-

movzx eax, WORD PTR val2[rip]

movzx edx, ax

movzx eax, WORD PTR val3[rip]

movzx eax, ax

imul eax, edx

movzx edx, WORD PTR val4[rip]

movzx edx, dx

lea ecx, [rdx-3]

mov DWORD PTR [rbp-4], ecx

cdq

idiv DWORD PTR [rbp-4]

mov WORD PTR val1[rip], ax

8-bit unsigned operands :-

  

movzx eax, BYTE PTR val2[rip]

movzx edx, al

movzx eax, BYTE PTR val3[rip]

movzx eax, al

imul eax, edx

movzx edx, BYTE PTR val4[rip]

movzx edx, dl

lea ecx, [rdx-3]

mov DWORD PTR [rbp-4], ecx

cdq

idiv DWORD PTR [rbp-4]

mov BYTE PTR val1[rip], al