compiler: Fix comparison of nested lists

artiq/compiler/transforms/artiq_ir_generator.py

@@ -1453,6 +1453,7 @@ class ARTIQIRGenerator(algorithm.Visitor):
             lhs_elt = self.append(ir.GetElem(lhs, index_phi))
             rhs_elt = self.append(ir.GetElem(rhs, index_phi))
             body_result = self.polymorphic_compare_pair(op, lhs_elt, rhs_elt)
+            body_end = self.current_block
 
             loop_body2 = self.add_block("compare.body2")
             self.current_block = loop_body2
@@ -1468,8 +1469,8 @@ class ARTIQIRGenerator(algorithm.Visitor):
             phi.add_incoming(compare_length, head)
             loop_head.append(ir.BranchIf(loop_cond, loop_body, tail))
             phi.add_incoming(ir.Constant(True, builtins.TBool()), loop_head)
-            loop_body.append(ir.BranchIf(body_result, loop_body2, tail))
+            body_end.append(ir.BranchIf(body_result, loop_body2, tail))
-            phi.add_incoming(body_result, loop_body)
+            phi.add_incoming(body_result, body_end)
 
             if isinstance(op, ast.NotEq):
                 result = self.append(ir.Select(phi,

artiq/test/lit/integration/list.py

@@ -7,3 +7,10 @@ assert (x, y) == (1, 2)
 
 lst = [1, 2, 3]
 assert [x*x for x in lst] == [1, 4, 9]
+
+assert [0] == [0]
+assert [0] != [1]
+assert [[0]] == [[0]]
+assert [[0]] != [[1]]
+assert [[[0]]] == [[[0]]]
+assert [[[0]]] != [[[1]]]