Move _split_constraints utility method to ConstrainedFrontend where i…

…t is used (#465)

* Move _split_constraints utility method to ConstrainedFrontend where it is used

* Improve lint

claripy/frontend.py

@@ -240,53 +240,3 @@ def _concrete_value(self, e):  # pylint:disable=no-self-use
 
     def _concrete_constraint(self, e):  # pylint:disable=no-self-use
         return self._concrete_value(e)
-
-    def _constraint_filter(self, c):  # pylint:disable=no-self-use
-        return c
-
-    @staticmethod
-    def _split_constraints(constraints, concrete=True):
-        """
-        Returns independent constraints, split from this Frontend's `constraints`.
-        """
-
-        splitted = []
-        for i in constraints:
-            splitted.extend(i.split(["And"]))
-
-        l.debug("... splitted of size %d", len(splitted))
-
-        concrete_constraints = []
-        variable_connections = {}
-        constraint_connections = {}
-        for n, s in enumerate(splitted):
-            l.debug("... processing constraint with %d variables", len(s.variables))
-
-            connected_variables = set(s.variables)
-            connected_constraints = {n}
-
-            if len(connected_variables) == 0:
-                concrete_constraints.append(s)
-
-            for v in s.variables:
-                if v in variable_connections:
-                    connected_variables |= variable_connections[v]
-                if v in constraint_connections:
-                    connected_constraints |= constraint_connections[v]
-
-            for v in connected_variables:
-                variable_connections[v] = connected_variables
-                constraint_connections[v] = connected_constraints
-
-        unique_constraint_sets = set()
-        for v in variable_connections:
-            unique_constraint_sets.add((frozenset(variable_connections[v]), frozenset(constraint_connections[v])))
-
-        results = []
-        for v, c_indexes in unique_constraint_sets:
-            results.append((set(v), [splitted[c] for c in c_indexes]))
-
-        if concrete and len(concrete_constraints) > 0:
-            results.append(({"CONCRETE"}, concrete_constraints))
-
-        return results

claripy/frontend_mixins/constraint_filter_mixin.py

@@ -12,8 +12,7 @@ def _constraint_filter(self, constraints):
         if len(constraints) == 0:
             return constraints
 
-        filtered = super()._constraint_filter(constraints)
-        ccs = [self._concrete_constraint(c) for c in filtered]
+        ccs = [self._concrete_constraint(c) for c in constraints]
         if False in ccs:
             raise UnsatError("Constraints contain False.")
         return tuple((o if n is None else o) for o, n in zip(constraints, ccs, strict=False) if n is not True)

claripy/frontends/constrained_frontend.py

@@ -10,7 +10,9 @@
 l = logging.getLogger("claripy.frontends.constrained_frontend")
 
 
-class ConstrainedFrontend(Frontend):  # pylint:disable=abstract-method
+class ConstrainedFrontend(Frontend):
+    """ConstrainedFrontend is a base class for all frontends that support constraints."""
+
     def __init__(self):
         Frontend.__init__(self)
         self.constraints = []
@@ -153,3 +155,54 @@ def is_true(self, e, extra_constraints=(), exact=None):
 
     def is_false(self, e, extra_constraints=(), exact=None):
         raise NotImplementedError("is_false() is not implemented")
+
+    #
+    # Some utility functions
+    #
+
+    @staticmethod
+    def _split_constraints(constraints, concrete=True):
+        """
+        Returns independent constraints, split from this Frontend's `constraints`.
+        """
+
+        splitted = []
+        for i in constraints:
+            splitted.extend(i.split(["And"]))
+
+        l.debug("... splitted of size %d", len(splitted))
+
+        concrete_constraints = []
+        variable_connections = {}
+        constraint_connections = {}
+        for n, s in enumerate(splitted):
+            l.debug("... processing constraint with %d variables", len(s.variables))
+
+            connected_variables = set(s.variables)
+            connected_constraints = {n}
+
+            if len(connected_variables) == 0:
+                concrete_constraints.append(s)
+
+            for v in s.variables:
+                if v in variable_connections:
+                    connected_variables |= variable_connections[v]
+                if v in constraint_connections:
+                    connected_constraints |= constraint_connections[v]
+
+            for v in connected_variables:
+                variable_connections[v] = connected_variables
+                constraint_connections[v] = connected_constraints
+
+        unique_constraint_sets = set()
+        for v, c in variable_connections.items():
+            unique_constraint_sets.add((frozenset(c), frozenset(constraint_connections[v])))
+
+        results = []
+        for v, c_indexes in unique_constraint_sets:
+            results.append((set(v), [splitted[c] for c in c_indexes]))
+
+        if concrete and len(concrete_constraints) > 0:
+            results.append(({"CONCRETE"}, concrete_constraints))
+
+        return results