compiler: Iteration for 1D ndarrays

artiq/compiler/transforms/artiq_ir_generator.py

@@ -510,7 +510,14 @@ class ARTIQIRGenerator(algorithm.Visitor):
 
     def iterable_get(self, value, index):
         # Assuming the value is within bounds.
-        if builtins.is_listish(value.type):
+        if builtins.is_array(value.type):
+            # Scalar indexing into ndarray.
+            if value.type.find()["num_dims"].value > 1:
+                raise NotImplementedError
+            else:
+                buffer = self.append(ir.GetAttr(value, "buffer"))
+                return self.append(ir.GetElem(buffer, index))
+        elif builtins.is_listish(value.type):
             return self.append(ir.GetElem(value, index))
         elif builtins.is_range(value.type):
             start  = self.append(ir.GetAttr(value, "start"))

artiq/compiler/transforms/inferencer.py

@@ -208,6 +208,14 @@ class Inferencer(algorithm.Visitor):
         if builtins.is_bytes(collection.type) or builtins.is_bytearray(collection.type):
             self._unify(element.type, builtins.get_iterable_elt(collection.type),
                         element.loc, None)
+        elif builtins.is_array(collection.type):
+            array_type = collection.type.find()
+            elem_dims = array_type["num_dims"].value - 1
+            if elem_dims > 0:
+                elem_type = builtins.TArray(array_type["elt"], types.TValue(elem_dims))
+            else:
+                elem_type = array_type["elt"]
+            self._unify(element.type, elem_type, element.loc, collection.loc)
         elif builtins.is_iterable(collection.type) and not builtins.is_str(collection.type):
             rhs_type = collection.type.find()
             rhs_wrapped_lhs_type = types.TMono(rhs_type.name, {"elt": element.type})

artiq/test/lit/integration/array.py

@@ -4,14 +4,14 @@
 ary = array([1, 2, 3])
 assert len(ary) == 3
 assert ary.shape == (3,)
-# FIXME: Implement ndarray indexing
-# assert [x*x for x in ary] == [1, 4, 9]
+assert [x * x for x in ary] == [1, 4, 9]
 
 # Reassign to an existing value to disambiguate type of empty array.
 empty_array = array([1])
 empty_array = array([])
 assert len(empty_array) == 0
 assert empty_array.shape == (0,)
+assert [x * x for x in empty_array] == []
 
 matrix = array([[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]])
 assert len(matrix) == 2