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The "jump threading" compiler optimization (aka -fthread-jump) turns conditional into unconditional branches on certain paths at the expense of code size. For hardware with branch prediction, speculative execution, and prefetching, this can greatly improve performance. However, there is no scientific publication or documentation at all. The Wikipedia article is very short and incomplete.
The linked article has an illustrated treatment of common code structures and how these optimizations work.
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(Score: 2) by Wootery on Tuesday November 03 2015, @11:39AM
This is the correct answer: having a 'single point-of-return' can be useful, especially in C where there's no RAII to handle cleanup automatically, the way you can in C++. It's also possible that single-point-of-return was required by coding guidelines that the authors were required to follow.
(It's perhaps ironic that garbage-collected languages, which generally lack RAII, also require special care with clean-up when it comes to things like closing files. Memory-management != resource-management, and no-one likes finalisers.)
I've also been told that old compilers would generate less efficient code when functions had multiple return points. (I don't know whether this is actually true, though.)