back.pysim: implement ArrayProxy.

nmigen/hdl/ast.py

@@ -776,10 +776,12 @@ class ArrayProxy(Value):
         return bits, sign
 
     def _lhs_signals(self):
-        return union((elem._lhs_signals() for elem in self._iter_as_values()), start=ValueSet())
+        signals = union((elem._lhs_signals() for elem in self._iter_as_values()), start=ValueSet())
+        return signals
 
     def _rhs_signals(self):
-        return union((elem._rhs_signals() for elem in self._iter_as_values()), start=ValueSet())
+        signals = union((elem._rhs_signals() for elem in self._iter_as_values()), start=ValueSet())
+        return self.index._rhs_signals() | signals
 
     def __repr__(self):
         return "(proxy (array [{}]) {!r})".format(", ".join(map(repr, self.elems)), self.index)

nmigen/hdl/xfrm.py

@@ -40,6 +40,10 @@ class ValueTransformer:
     def on_Repl(self, value):
         return Repl(self.on_value(value.value), value.count)
 
+    def on_ArrayProxy(self, value):
+        return ArrayProxy([self.on_value(elem) for elem in value._iter_as_values()],
+                          self.on_value(value.index))
+
     def on_unknown_value(self, value):
         raise TypeError("Cannot transform value '{!r}'".format(value)) # :nocov:
 
@@ -62,6 +66,8 @@ class ValueTransformer:
             new_value = self.on_Cat(value)
         elif isinstance(value, Repl):
             new_value = self.on_Repl(value)
+        elif isinstance(value, ArrayProxy):
+            new_value = self.on_ArrayProxy(value)
         else:
             new_value = self.on_unknown_value(value)
         if isinstance(new_value, Value):