I believe that `noipp` suffix should be dropped from plain version:

```
static void Exp_32f(...)
{
    ... cpu code ...
}

#ifdef HAVE_IPP
static void Exp_32f_ipp(...)
{
  if (ippStsNoErr == ippsExp_32f_A21(x, y, n))
    return;
  Exp_32f(...)
}
#define Exp_32f Exp_32f_ipp
#endif

...
  // use as usually
  Exp_32f(...); // plain or IPP version will be called
...
```