(defun apple (i)
(+ i i))

(defun melon (i)
(* i i))

(defun fruit (n)
(dotimes (i n)
(apple i) (apple (melon i))))

(with-function-call-count (apple melon) (fruit 100))

returns

NIL           --> which is what (fruit 100) returns
(200 100)     --> which is the number of times
                  apple and melon were called

Unfortunately this does not work with builtin
functions such as * or + or eigen or what-have-you
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(time-form (eigen (identity-matrix 10)))

runs eigen 20 times on the identity matrix and takes
the average runtime (this is total time, ie. it
may include gc).
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(breakon 'apple)

sets a break at the beginning of apple, which means
for instance that fruit will stop as soon as it
gets to apple.
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