diff --git a/loopy/codegen/instruction.py b/loopy/codegen/instruction.py
index 11288e8754ae521c312aadd6f45d653de7224306..5fa54aeee91b5c41531e0dd5bfd7ab97323b19ae 100644
--- a/loopy/codegen/instruction.py
+++ b/loopy/codegen/instruction.py
@@ -151,7 +151,8 @@ def generate_assignment_instruction_code(codegen_state, insn):
         if codegen_state.vectorization_info and is_vector:
             raise Unvectorizable("tracing does not support vectorization")
 
-        lhs_code = str(insn.assignee)
+        from pymbolic.mapper.stringifier import PREC_NONE
+        lhs_code = codegen_state.expression_to_code_mapper(insn.assignee, PREC_NONE)
 
         from cgen import Statement as S  # noqa