[Ada] Fix detection of overlapping actuals with renamings

[Pierre-Marie de Rodat]

Simplify detection of renamings within actuals that denote the same
object. This code only needs to take object renamings and shouldn't care
about renamings of subprogram, packages or exceptions.

Tested on x86_64-pc-linux-gnu, committed on trunk

gcc/ada/

        * sem_util.adb (Is_Object_Renaming): Rename from Is_Renaming;
        simplify; adapt callers.
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -7262,8 +7262,8 @@ package body Sem_Util is
    -------------------------
 
    function Denotes_Same_Object (A1, A2 : Node_Id) return Boolean is
-      function Is_Renaming (N : Node_Id) return Boolean;
-      --  Return true if N names a renaming entity
+      function Is_Object_Renaming (N : Node_Id) return Boolean;
+      --  Return true if N names an object renaming entity
 
       function Is_Valid_Renaming (N : Node_Id) return Boolean;
       --  For renamings, return False if the prefix of any dereference within
@@ -7271,35 +7271,16 @@ package body Sem_Util is
       --  renamed object_name contains references to variables or calls on
       --  nonstatic functions; otherwise return True (RM 6.4.1(6.10/3))
 
-      -----------------
-      -- Is_Renaming --
-      -----------------
+      ------------------------
+      -- Is_Object_Renaming --
+      ------------------------
 
-      function Is_Renaming (N : Node_Id) return Boolean is
+      function Is_Object_Renaming (N : Node_Id) return Boolean is
       begin
-         if not Is_Entity_Name (N) then
-            return False;
-         end if;
-
-         case Ekind (Entity (N)) is
-            when E_Variable | E_Constant =>
-               return Present (Renamed_Object (Entity (N)));
-
-            when E_Exception
-               | E_Function
-               | E_Generic_Function
-               | E_Generic_Package
-               | E_Generic_Procedure
-               | E_Operator
-               | E_Package
-               | E_Procedure
-            =>
-               return Present (Renamed_Entity (Entity (N)));
-
-            when others =>
-               return False;
-         end case;
-      end Is_Renaming;
+         return Is_Entity_Name (N)
+           and then Ekind (Entity (N)) in E_Variable | E_Constant
+           and then Present (Renamed_Object (Entity (N)));
+      end Is_Object_Renaming;
 
       -----------------------
       -- Is_Valid_Renaming --
@@ -7307,7 +7288,7 @@ package body Sem_Util is
 
       function Is_Valid_Renaming (N : Node_Id) return Boolean is
       begin
-         if Is_Renaming (N)
+         if Is_Object_Renaming (N)
            and then not Is_Valid_Renaming (Renamed_Entity (Entity (N)))
          then
             return False;
@@ -7494,12 +7475,12 @@ package body Sem_Util is
       --  no references to variables nor calls on nonstatic functions (RM
       --  6.4.1(6.11/3)).
 
-      elsif Is_Renaming (A1)
+      elsif Is_Object_Renaming (A1)
         and then Is_Valid_Renaming (A1)
       then
          return Denotes_Same_Object (Renamed_Entity (Entity (A1)), A2);
 
-      elsif Is_Renaming (A2)
+      elsif Is_Object_Renaming (A2)
         and then Is_Valid_Renaming (A2)
       then
          return Denotes_Same_Object (A1, Renamed_Entity (Entity (A2)));