Simpler, more robust emulation of calls to variadic functions:

- C function types and Cminor signatures annotated by calling conventions.
  esp. vararg / not vararg
- Cshmgen: generate correct code for function call where there are
  more arguments than listed in the function prototype.  This is
  still undefined behavior according to the formal semantics,
  but correct code is generated.
- C2C, */PrintAsm.ml: remove "printf$iif" hack.
- powerpc/, checklink/: don't generate stubs for variadic functions.


git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2386 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e

1 files changed, 24 insertions, 26 deletions

diff --git a/cfrontend/PrintCsyntax.ml b/cfrontend/PrintCsyntax.ml
index 4db89761..758323ee 100644
--- a/cfrontend/PrintCsyntax.ml
+++ b/cfrontend/PrintCsyntax.ml
@@ -88,11 +88,6 @@ let attributes a =
 let name_optid id =
   if id = "" then "" else " " ^ id
 
-(*
-let parenthesize_if_pointer id =
-  if String.length id > 0 && id.[0] = '*' then "(" ^ id ^ ")" else id
-*)
-
 let rec name_cdecl id ty =
   match ty with
   | Tvoid ->
@@ -111,24 +106,26 @@ let rec name_cdecl id ty =
       name_cdecl id' t
   | Tarray(t, n, a) ->
       name_cdecl (sprintf "%s[%ld]" id (camlint_of_coqint n)) t
-  | Tfunction(args, res) ->
+  | Tfunction(args, res, cconv) ->
       let b = Buffer.create 20 in
       if id = ""
       then Buffer.add_string b "(*)"
       else Buffer.add_string b id;
       Buffer.add_char b '(';
-      begin match args with
+      let rec add_args first = function
       | Tnil ->
-          Buffer.add_string b "void"
-      | _ ->
-          let rec add_args first = function
-          | Tnil -> ()
-          | Tcons(t1, tl) ->
-              if not first then Buffer.add_string b ", ";
-              Buffer.add_string b (name_cdecl "" t1);
-              add_args false tl in
-          add_args true args
-      end;
+          if first then
+            Buffer.add_string b
+               (if cconv.cc_vararg then "..." else "void")
+          else if cconv.cc_vararg then
+            Buffer.add_string b ", ..."
+          else
+            ()
+      | Tcons(t1, tl) ->
+          if not first then Buffer.add_string b ", ";
+          Buffer.add_string b (name_cdecl "" t1);
+          add_args false tl in
+      add_args true args;
       Buffer.add_char b ')';
       name_cdecl (Buffer.contents b) res
   | Tstruct(name, fld, a) ->
@@ -351,16 +348,17 @@ and print_stmt_for p s =
   | _ ->
       fprintf p "({ %a })" print_stmt s
 
-let name_function_parameters fun_name params =
+let name_function_parameters fun_name params cconv =
   let b = Buffer.create 20 in
   Buffer.add_string b fun_name;
   Buffer.add_char b '(';
   begin match params with
   | [] ->
-      Buffer.add_string b "void"
+      Buffer.add_string b (if cconv.cc_vararg then "..." else "void")
   | _ ->
       let rec add_params first = function
-      | [] -> ()
+      | [] ->
+          if cconv.cc_vararg then Buffer.add_string b "..."
       | (id, ty) :: rem ->
           if not first then Buffer.add_string b ", ";
           Buffer.add_string b (name_cdecl (extern_atom id) ty);
@@ -373,7 +371,7 @@ let name_function_parameters fun_name params =
 let print_function p id f =
   fprintf p "%s@ "
             (name_cdecl (name_function_parameters (extern_atom id)
-                                                  f.fn_params)
+                                                  f.fn_params f.fn_callconv)
                         f.fn_return);
   fprintf p "@[<v 2>{@ ";
   List.iter
@@ -385,10 +383,10 @@ let print_function p id f =
 
 let print_fundef p id fd =
   match fd with
-  | External(EF_external(_,_), args, res) ->
+  | External(EF_external(_,_), args, res, cconv) ->
       fprintf p "extern %s;@ @ "
-                (name_cdecl (extern_atom id) (Tfunction(args, res)))
-  | External(_, _, _) ->
+                (name_cdecl (extern_atom id) (Tfunction(args, res, cconv)))
+  | External(_, _, _, _) ->
       ()
   | Internal f ->
       print_function p id f
@@ -474,7 +472,7 @@ let rec collect_type = function
   | Tlong _ -> ()
   | Tpointer(t, _) -> collect_type t
   | Tarray(t, _, _) -> collect_type t
-  | Tfunction(args, res) -> collect_type_list args; collect_type res
+  | Tfunction(args, res, _) -> collect_type_list args; collect_type res
   | Tstruct(id, fld, _) | Tunion(id, fld, _) ->
       let s = extern_atom id in
       if not (StructUnion.mem s !struct_unions) then begin
@@ -552,7 +550,7 @@ let collect_function f =
 
 let collect_globdef (id, gd) =
   match gd with
-  | Gfun(External(_, args, res)) -> collect_type_list args; collect_type res
+  | Gfun(External(_, args, res, _)) -> collect_type_list args; collect_type res
   | Gfun(Internal f) -> collect_function f
   | Gvar v -> collect_type v.gvar_info