Experiment with unassume for mutex analysis #1715
                
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This is a quick proof-of-concept for an idea I had a while ago: unassume for variable protection in mutex analysis.
It is the first example of a non–value-domain unassume operator.
To do so, this also implements the custom
protected_byYAML witness entry type from our COOP 2023 talk, including generation and validation.On test 13/01 it reduces evals 23 → 19, so it conceptually seems to work (even in a trivial case!). But this needs more evaluation to see its potential.
TODO
location_mutexentry type as well.