Exercise 7            Name       _________________    Points __/19

Part A. Give the expansions for the following macros.

Example:
Macro
Definition		 Use in
Program		 Macro
Expansion		 
_Div    Macro  N
        Mov    eDx, 0
        Mov    eBx, &N    
        Div    eBx
endm
 
Call  ReadInt
_Div  34
Call  WriteInt   

  
 
Call  ReadInt
XOR   eDX,eDX
Mov   eBx, 34
Div   eBx
Call  WriteInt
1.   (2)
Macro
Definition		 Use in
Program		 Macro
Expansion		 
_Swap Macro  A, B
      PushA  
      Mov    eAx, &A       
      Mov    eBx, &B
      Mov    &A, eBx
      Mov    &B, eAx
      PopA
endm
 
_Swap X, Y     
   

  

2.  (4)
Macro
Definition		 Use in
Program		 Macro
Expansion		 
_DCG Macro  X, Y
       local  L
  ifb <&y>
      exitm
  endif
  while&L:
       cmp    &Y, 0
       Jne    do&L
       Jmp    endwhile&L    
   do&L:
       _Swap  &X, &Y
       Jmp    while&L
  endwhile&L:
endm
 
_DCG A, B      

   

  

3. (4) Give the macro to compute the power of xn, x is signed and n unsigned 8 bit, both may be constants. The result is in Ax. No overflow checking is performed. Use the following real operations. 

      Mov  eAx, 1
      Mov  eCx, x
      Mov  Bh, n
  while:
      Cmp  Bh, 0
      JA   do
      Jmp  endwhile
  do: Imul eCx
      Dec  Bh
      Jmp  while
  endwhile:
Part B.    Give the results of the following bit operations:
     Examples: 
MOV  AL,01001010B             ZF = _0_
AND  AL,00001010B             AL = _00001010_

MOV  AL,00011100B             ZF = _0_
STC                           CF = _0_
RCR  AL,1                     AL = _10001110_
4. (3)  MOV  CL,5
        CLC                           ZF = __
        MOV  AL,11101110B             CF = __
        ROL  AL,CL                    AL = _____________

5. (3)  MOV  CL, 4                    ZF = __
        MOV  AL,10100000B             CF = __
        SAR  AL, CL                   AL = _____________

6. (3)  MOV  AL, 10010001B            ZF = __
        OR   AL, 10000001B            AL = _____________




Document last modified: