diff options
Diffstat (limited to 'cfrontend/SimplExpr.v')
| -rw-r--r-- | cfrontend/SimplExpr.v | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/cfrontend/SimplExpr.v b/cfrontend/SimplExpr.v index a5306b4b..0a191f29 100644 --- a/cfrontend/SimplExpr.v +++ b/cfrontend/SimplExpr.v @@ -121,6 +121,20 @@ Function makeif (a: expr) (s1 s2: statement) : statement := | None => Sifthenelse a s1 s2 end. +(** Smart constructors for [&] and [*]. They optimize away [&*] and [*&] sequences. *) + +Definition Ederef' (a: expr) (t: type) : expr := + match a with + | Eaddrof a' t' => if type_eq t (typeof a') then a' else Ederef a t + | _ => Ederef a t + end. + +Definition Eaddrof' (a: expr) (t: type) : expr := + match a with + | Ederef a' t' => if type_eq t (typeof a') then a' else Eaddrof a t + | _ => Eaddrof a t + end. + (** Translation of pre/post-increment/decrement. *) Definition transl_incrdecr (id: incr_or_decr) (a: expr) (ty: type) : expr := @@ -220,7 +234,7 @@ Fixpoint transl_expr (dst: destination) (a: Csyntax.expr) : mon (list statement ret (finish dst nil (Evar x ty)) | Csyntax.Ederef r ty => do (sl, a) <- transl_expr For_val r; - ret (finish dst sl (Ederef a ty)) + ret (finish dst sl (Ederef' a ty)) | Csyntax.Efield r f ty => do (sl, a) <- transl_expr For_val r; ret (finish dst sl (Efield a f ty)) @@ -244,7 +258,7 @@ Fixpoint transl_expr (dst: destination) (a: Csyntax.expr) : mon (list statement ret (finish dst (sl1 ++ sl2) a2) | Csyntax.Eaddrof l ty => do (sl, a) <- transl_expr For_val l; - ret (finish dst sl (Eaddrof a ty)) + ret (finish dst sl (Eaddrof' a ty)) | Csyntax.Eunop op r1 ty => do (sl1, a1) <- transl_expr For_val r1; ret (finish dst sl1 (Eunop op a1 ty)) |