@neauoire Wow, you move fast ^_^
I am way behind in the replies, I will get back to it when I have more time.
I wonder if it is enough to keep track of the "wasted information" to reverse any computation. In principle that is the case: the idea is that a reversible computation simply performs permutations on the bits.
@neauoire In practice, it is not so clear to me, I guess it depends on the definition of "wasted information".
What is also tricky is what happens with recursion, i.e. what is the minimal information required to reverse a recursive computation.