ByteCode; PHP; Zend Optimizer

I am needing to write an app in PHP however:

function foo ($bar)
{
if ($bar === 'boo')
{
return true;
}
else
{
return false;
}
}// End Function

index.php

...

foo($bar);
...



-----

x.php

....
foo($bar);
....

That is an example I don't want to hear anything about the specifics above.

Anyway, see the delemia; I could write the code in place of the function and it would run that tiny bit faster, however to the developer it is harder and annoying. So my question is:

If I "encode" something with Zend/Ioncube/Source Guardain will that turn the stuff into bytecode and do away with the functions... ie. convert the nice code with functions into (compiled but sorta means) the "Expanded" form. (eg. the if's are inplace of the function)

I hope this makes sense.

Thanks