Winter 18-19
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* spend longer on caller/callee registers and examples - people confused in lab
* not enough time for thorough recursion example at end

Spring 18-19
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* Cut review at start
* need to spend more time with caller-callee; make interactive example each for caller and callee registers to show the problem (only 1 copy of registers!), and then the solution (guidelines for register use)
* didn't have time to get to recursion example
* consider cutting the dissection of the jmp instruction, cool to see interaction with %rip, but maybe not super-essential