str := 'thisistheargument'#0;
asm
    int 3;

    push ebx;
    push esi;

    mov eax, str;
    push eax;
    mov ecx, dword ptr ss:[classInst];
    mov ecx, dword ptr ss:[ecx];

    mov eax, dword ptr ss:[ecx+$1c];
    call eax;

    pop esi;
    pop ebx;
end;