program PassByRefDemo;
#include( “stdlib.hhf” );
var 
 i: int32;
 j: int32;
 
 procedure pbr( var a:int32; var b:int32 );
   const
     aa: text := “(type int32 [ebx])”;
     bb: text := “(type int32 [ebx])”;
 
 begin pbr;
 
   push( eax );
   push( ebx ); // Need to use EBX to dereference a and b.
 
   // a = -1;
   mov( a, ebx ); // Get ptr to the “a” variable.
   mov( -1, aa ); // Store -1 into the “a” parameter.
 
   // b = -2;
   mov( b, ebx ); // Get ptr to the “b” variable.
   mov( -2, bb ); // Store -2 into the “b” parameter.
 
   // Print the sum of a+b.
   // Note that ebx currently contains a pointer to “b”.
   mov( bb, eax );
   mov( a, ebx ); // Get ptr to “a” variable.
   add( aa, eax );
   stdout.put( “a+b=”, (type int32 eax), nl );
 
 end pbr;
 
begin PassByRefDemo;
 // Give i and j some initial values so
 // we can see that pass by reference will
 // overwrite these values.
 
 mov( 50, i );
 mov( 25, j );
 
 // Call pbr passing i and j by reference
 
 pbr( i, j );
 
 // Display the results returned by pbr.
 stdout.put
 ( 
  “i= “, i, nl, 
  “j= “, j, nl 
 );
end PassByRefDemo;