CSC231 Exercises with the MOV instruction

--D. Thiebaut (talk) 12:58, 28 September 2015 (EDT)

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Problem #1

Translate this program in a language close to Java and C/C++, into assembly

    int Table1[5] = { 1, 10, 20, 30, 40};
    int Table2[5];
    String msg1 = "Hello world!";
    String msg2 = "                 ";

    // some assignments
    Table1[0] = Table2[0]

    Table2[0] = 3;
    Table2[1] = 4;
    Table2[2] = 5;
    Table2[3] = 6;
    Table2[4] = 10;

    Table1[0] = Table2[0]
    Table1[1] = Table2[4]

    msg2[0] = msg1[0];
    msg1[11] = '\n';

Problem #2

How long does it take a 1GHz Pentium to execute the section labeled "some assignments"?

Problem 3

• Draw the RAM, store the variables that are declared in the program below, and show how the RAM and the registers get modified by each instruction.

x      dd        0x11223344
y      dw        0x1234, 0xffff, 0, 1
z      db        "hello", 10, 10

        mov     eax, dword[x]
        mov     al, 0
        mov     dword[x], eax

        mov     ax, word[y]
        mov     dword[x], eax

        mov     bx, word[y+2]
        mov     word[y], bx

        mov     al, 'X'
        mov     byte[z], al
        mov     byte[z+1], al
        mov     byte[z+2], al

Problem #4

Same as Problem #3, but with much more complex instructions.

x      dd        0x11223344
y      dw        0x1234, 0xffff, 0, 1
z      db        "hello", 10, 10

        mov     eax, dword[x]
        mov     dword[y], eax

        mov     ebx, dword[y+1]
        mov     word[x], bx

        mov     edx, 0
        mov     dx, word[z]
        mov     dword[z], edx

        mov     al, 'X'
        mov     byte[z], al
        mov     byte[z+1], al
        mov     byte[z+2], al