message: Use Patricia tree abstract environments in the constant propagation pass
  Summary: Using PatriciaTreeMapAbstractEnvironment instead of HashedAbstractEnvironment brings the running time of the pass down from 17.3 to 14.5 seconds.
diff: #include "ControlFlow.h"
  #include "FixpointIterators.h"
  -#include "HashedAbstractEnvironment.h"
  #include "HashedSetAbstractDomain.h"
  +#include "PatriciaTreeMapAbstractEnvironment.h"
  /**
  *This class represents constant values living in the following lattice:
  @@ -114,7 +114,7 @@ class ConstantDomain final
  std::ostream& operator<<(std::ostream& o, const ConstantDomain& cd);
  using ConstPropEnvironment =
  - HashedAbstractEnvironment<uint16_t, ConstantDomain>;
  + PatriciaTreeMapAbstractEnvironment<uint16_t, ConstantDomain>;
  class ConstPropEnvUtil {
  public:
  