Are there people who have done so much work before PhD that they get a PhD automatically?

This question addresses why it's a bad idea to try to do a lot of independent work before PhD in the hope of finishing PhD quickly.

Nevertheless, are there famous examples of people who have done so much work before PhD that they get a PhD pretty much automatically (say, 1-2 years or less)?

Answer

The closest example I can think of is Mihai Pătraşcu. After publishing several extremely strong results as an undergraduate, Mihai earned an MS in one year and then a PhD in one year, all in computer science at MIT.