INVOKE Directive

The INVOKE directive pushed arguments on the stack and calls a procedure. It is a convenient replacement for the CALL instruction because multiple arguments can be passed by using a single line of code. The syntax is 

 
     INVOKE  procedureName [, argumentList]
argumentList is an optional comma-delimited list of arguments passed to the procedure. Argument types are listed below.

Type Examples
Immediate value 10, 3000h, OFFSET myList, TYPE array
Integer expression (10 * 20), COUNT
Variable myList, array, myWord, myDword
Address expression [myList+2], [ebx+esi]
Register eax, bl, edi
ADDR name ADDR myList
OFFSET name OFFSET myList

 An ABS Procedure Using CALL   An ABS Procedure Using INVOKE  

 
 INCLUDE Irvine32.inc

 
 .code

 
 main PROC

 
      push  -23

 
      call  abs

 
      exit

 
 main ENDP


 
 ;; Find |value|

 
 abs PROC

 
      pop   edx    ; return address

 
      pop   eax    ; EAX = value

 
      cmp   eax, 0

    

     

 

       

     
     

 

    
    
    


     

     		
    

   

 
      neg   eax

 
 POS: call  WriteInt

 
      push  edx

 
      ret

 
 abs ENDP

 
 END main
 

 
 INCLUDE Irvine32.inc

 
 .code
 

 
 ;; Find |value|

 
 abs PROC, value:SDWORD

 
      cmp   value, 0

    

     

 

       

     
     

 

    
    
    


     

     		
    

   

 
      neg   value

 
 POS: mov   eax, value

 
      call  WriteInt

 
      ret

 
 abs ENDP


 
 ;; main proc is after abs proc.

 
 main PROC

 
      INVOKE  abs, -23

 
      exit

 
 main ENDP

 
 END main


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      ― Unknown