diff --git a/theories/simd_execute.v b/theories/simd_execute.v
index b8a8d2e2..56f6fe5e 100644
--- a/theories/simd_execute.v
+++ b/theories/simd_execute.v
@@ -13,7 +13,7 @@ Parameter app_vunop_str : vunop -> string -> string.
 Parameter app_vbinop_str : vbinop -> string -> string -> string.
 Parameter app_vternop_str : vternop -> string -> string -> string -> string.
 Parameter app_vtestop_str : vtestop -> string -> string.
-Parameter app_vshiftop_str : vtestop -> string -> string -> string.
+Parameter app_vshiftop_str : vshiftop -> string -> string -> string.
 
 End SIMD_ops.