Sometimes, the behavior of the optimization pipeline seems to be non-deterministic.

Example:
./build/bin/thorin -d mem -o - lit/mem/no_mem.thorin -VVVV
in
https://github.com/NeuralCoder3/thorin2/tree/ad_ptr_merge
702d848

The issue might be due to the add_mem optimization, the pipeline builder, or an underlying bug in thorin.

This behavior might also be a side effect of the previous (not merged yet) changes to mem and clos conv with long-reaching impact that did not manifest up to now.