Factor out bind_lvalue

git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@1715 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e

1 files changed, 18 insertions, 0 deletions

diff --git a/cparser/Transform.ml b/cparser/Transform.ml
index 4fd83ae..1cafaba 100644
--- a/cparser/Transform.ml
+++ b/cparser/Transform.ml
@@ -40,6 +40,24 @@ let get_temps () =
   temporaries := [];
   List.rev temps
 
+(* Bind a l-value to a temporary variable if it is not invariant. *)
+
+let rec invariant_lvalue env e =
+  match e.edesc with
+  | EVar _ -> true
+  | EUnop(Odot _, e1) -> invariant_lvalue env e1
+  | _ -> false
+
+let bind_lvalue env e fn =
+  if invariant_lvalue env e then
+    fn e
+  else begin
+    let tmp = new_temp (TPtr(e.etyp, [])) in
+    ecomma (eassign tmp (addrof e))
+           (fn {edesc = EUnop(Oderef, tmp); etyp = e.etyp})
+  end
+
+
 (* Generic transformation *)
 
 let program