diff --git a/artiq/compiler/transforms/artiq_ir_generator.py b/artiq/compiler/transforms/artiq_ir_generator.py
index fa5912999..a77969fc9 100644
--- a/artiq/compiler/transforms/artiq_ir_generator.py
+++ b/artiq/compiler/transforms/artiq_ir_generator.py
@@ -1510,21 +1510,12 @@ class ARTIQIRGenerator(algorithm.Visitor):
         if name not in self.array_binop_funcs:
 
             def body_gen(result, lhs, rhs):
-                # TODO: Move into caller for correct location information (or pass)?
-                shape = self.append(ir.GetAttr(lhs, "shape"))
-                rhs_shape = self.append(ir.GetAttr(rhs, "shape"))
-                self._make_check(
-                    self.append(ir.Compare(ast.Eq(loc=None), shape, rhs_shape)),
-                    lambda: self.alloc_exn(
-                        builtins.TException("ValueError"),
-                        ir.Constant("operands could not be broadcast together",
-                                    builtins.TStr())))
-                # We assume result has correct shape; could just pass buffer pointer
-                # as well.
-
+                # At this point, shapes are assumed to match; could just pass buffer
+                # pointer for two of the three arrays as well.
                 result_buffer = self.append(ir.GetAttr(result, "buffer"))
                 lhs_buffer = self.append(ir.GetAttr(lhs, "buffer"))
                 rhs_buffer = self.append(ir.GetAttr(rhs, "buffer"))
+                shape = self.append(ir.GetAttr(result, "shape"))
                 num_total_elts = self._get_total_array_len(shape)
 
                 def loop_gen(index):
@@ -1709,9 +1700,15 @@ class ARTIQIRGenerator(algorithm.Visitor):
             lhs = self.visit(node.left)
             rhs = self.visit(node.right)
 
-            # Array op implementation will check for matching shape.
-            # TODO: Broadcasts; select the widest shape.
             shape = self.append(ir.GetAttr(lhs, "shape"))
+            # TODO: Broadcasts; select the widest shape.
+            rhs_shape = self.append(ir.GetAttr(rhs, "shape"))
+            self._make_check(
+                self.append(ir.Compare(ast.Eq(loc=None), shape, rhs_shape)),
+                lambda: self.alloc_exn(
+                    builtins.TException("ValueError"),
+                    ir.Constant("operands could not be broadcast together",
+                                builtins.TStr())))
             result = self._allocate_new_array(node.type.find()["elt"], shape)
 
             func = self._get_array_binop(node.op, node.type, node.left.type, node.right.type)