For example: “Do you like him like him?”
“It wasn’t rape rape”
I’m sure there are more but I can’t think of any.
Is there some particular example in a book or show where you see this? I haven’t seen this before your thread.
I can’t add anything but an example from UK common usage:
‘Going out’ = going out for an evening.
‘Going out out’ = going on to a nightclub after an evening out.
The rape one is Whoopi Golberg’s response to Roman Polanski’s arrest. The like him one is just something I’ve heard in IRL and probably in a romcom or sitcom or two.
A common one I remember from my software development days:
“You say all your tasks are done, but are they *done *done?”
No idea when people started doing this though. Since the early 90’s at least.
I think it’s more clarification, rather than emphasis. For example:
Have you seen my cat?
Do you mean a ‘cat’ cat; or a ‘cheetah’ cat?
That is, someone is asking if the word that someone used is the commonly-accepted definition of the word (the word being emphasised); or if it is the same word with a different definition. In Whoopi’s case, she was saying that yes, Polanski legally raped an underage girl; but he didn’t ‘rape’ her in the way that most people think of ‘rape’.
I found this:
(and more significantly, this: Contrastive focus reduplication - Wikipedia )
(I was looking for the origin on the Stage-Irish ‘At all at all’)
If you’ve never heard “does she like him like him,” then I’m guessing you never watched The Wonder Years. 
I see it as a variation of the type of phrase:
Boys will be boys.
Where the word is used once to denote an essential nature and the second time to denote the mundane, less essential usage. As for origin, do you mean *origin *origin, or just origin? 
Crap. You stole the joke I was going to use. I mean, you didn’t steal it steal it, but you you stole it.
I disagree. At least in the “like him like him” form, it’s to denote a fine shade of meaning while specifically avoiding a taboo term.
I agree (with you) - I don’t see much relation to reiteration as in ‘boys will be boys’.
The construction we’re discussing here, is similar in purpose to the (non-repetitive) “do you mean funny-ha ha, or funny-peculiar?”
Google-fu is strong with this one.
Excellent link!
Reduplication is a pretty common thing to find in languages. One thing I was always surprised about in Cameroon was that it was used in ALL languages- be it French, English or local languages. If you wanted a small piece of bread you could ask for “that small small bread”, “le petit petit pain la” or “beret petal petal hatoe.” Verbs were also repeated- especially in French. It was always “allez allez!” or “on vas bouger bouger” or “je vais manger manger ce soir.”
I agree about the finer shade of meaning, but what’s the taboo term?
In that example, love. Lots of little kids are very shy about using that term to describe what adults would call “romantic feelings.” Hence “like him like him” denotes “liking him in that way” without using the verboten word.
I don’t think it’s to avoid saying love. Romantic feelings are not the same thing as love. I’ve liked many women in that way, but have loved only a few, and then only after developing an actual relationship. It wasn’t any different when I was fourteen.
Your experience is certainly as valid as anyone else’s. In my elementary school, one of the most powerful taunts available was to accuse someone of loving someone else. The widely-understood and completely unspoken but socially-approved method of avoiding the social pariah status that went with admitting to loving someone was to say you like them and then clarify/expound that you, you know, liked them liked them.
Now pay attention Boy, I think, I say, I think that this heah repetition been commencing for many a year now. [/Foghorn Leghorn]
The earliest example of this that I can remember is an old commercial for Glade (I think) air freshener spray. This ad campaign was based on the idea that the product was being referred to as an “air conditioner”. So there was this middle aged couple with New York accents, and the guy says something like, “You bought an air conditioner?!” And the lady says, “Not an air conditioner air conditioner – an air conditioner.” I’m guessing that was from the 70s or 80s.