ada: Reuse and simplify counting the length of various lists

Use utility routines to compute number of elements in lists of nodes and chains
of formal parameters. Code cleanup; semantics is unaffected.

gcc/ada/ChangeLog:

	* exp_aggr.adb (Others_Check): Reuse List_Length; tune whitespace.
	* exp_ch3.adb (Constrain_Array): Remove counting of constraints.
	* exp_disp.adb (Make_DT): Use Elist utility routines; tune whitespace.
	* sem_ch12.adb (Formal_Dimensions): Reuse List_Length.
	(Valid_Default_Attribute): Reuse Number_Formals.
	* sem_prag.adb (Process_Convention): Likewise.
	* sem_util.adb (Normalize_Actuals): Likewise.
	(Check_Function_Writable_Actuals): Reuse List_Length.

6 files changed, 26 insertions, 84 deletions

diff --git a/gcc/ada/exp_aggr.adb b/gcc/ada/exp_aggr.adb
index 64bb05c..dae9d4e 100644
--- a/gcc/ada/exp_aggr.adb
+++ b/gcc/ada/exp_aggr.adb
@@ -5352,17 +5352,10 @@ package body Exp_Aggr is
                --  Count the number of discrete choices. Start with -1 because
                --  the others choice does not count.
 
-               --  Is there some reason we do not use List_Length here ???
-
                Nb_Choices := -1;
                Assoc := First (Component_Associations (Sub_Aggr));
                while Present (Assoc) loop
-                  Choice := First (Choice_List (Assoc));
-                  while Present (Choice) loop
-                     Nb_Choices := Nb_Choices + 1;
-                     Next (Choice);
-                  end loop;
-
+                  Nb_Choices := Nb_Choices + List_Length (Choice_List (Assoc));
                   Next (Assoc);
                end loop;
 
@@ -5379,12 +5372,7 @@ package body Exp_Aggr is
          --  choice then compute the number or positional elements.
 
          if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
-            Expr := First (Expressions (Sub_Aggr));
-            Nb_Elements := Uint_0;
-            while Present (Expr) loop
-               Nb_Elements := Nb_Elements + 1;
-               Next (Expr);
-            end loop;
+            Nb_Elements := UI_From_Int (List_Length (Expressions (Sub_Aggr)));
 
          --  If the aggregate contains discrete choices and an others choice
          --  compute the smallest and largest discrete choice values.
@@ -5395,7 +5383,7 @@ package body Exp_Aggr is
                Table : Case_Table_Type (1 .. Nb_Choices);
                --  Used to sort all the different choice values
 
-               J    : Pos := 1;
+               J : Pos := 1;
 
             begin
                Assoc := First (Component_Associations (Sub_Aggr));
diff --git a/gcc/ada/exp_ch3.adb b/gcc/ada/exp_ch3.adb
index 71bca1c..a68b4f1 100644
--- a/gcc/ada/exp_ch3.adb
+++ b/gcc/ada/exp_ch3.adb
@@ -4300,10 +4300,9 @@ package body Exp_Ch3 is
            (SI         : Node_Id;
             Check_List : List_Id)
          is
-            C                     : constant Node_Id := Constraint (SI);
-            Number_Of_Constraints : Nat := 0;
-            Index                 : Node_Id;
-            S, T                  : Entity_Id;
+            C     : constant Node_Id := Constraint (SI);
+            Index : Node_Id;
+            S, T  : Entity_Id;
 
             procedure Constrain_Index
               (Index      : Node_Id;
@@ -4341,12 +4340,6 @@ package body Exp_Ch3 is
                T := Designated_Type (T);
             end if;
 
-            S := First (Constraints (C));
-            while Present (S) loop
-               Number_Of_Constraints := Number_Of_Constraints + 1;
-               Next (S);
-            end loop;
-
             --  In either case, the index constraint must provide a discrete
             --  range for each index of the array type and the type of each
             --  discrete range must be the same as that of the corresponding
@@ -4358,7 +4351,7 @@ package body Exp_Ch3 is
 
             --  Apply constraints to each index type
 
-            for J in 1 .. Number_Of_Constraints loop
+            while Present (S) loop
                Constrain_Index (Index, S, Check_List);
                Next (Index);
                Next (S);
diff --git a/gcc/ada/exp_disp.adb b/gcc/ada/exp_disp.adb
index f250117..9fcc469 100644
--- a/gcc/ada/exp_disp.adb
+++ b/gcc/ada/exp_disp.adb
@@ -4650,7 +4650,6 @@ package body Exp_Disp is
       Name_ITable        : Name_Id;
       Nb_Prim            : Nat := 0;
       New_Node           : Node_Id;
-      Num_Ifaces         : Nat := 0;
       Parent_Typ         : Entity_Id;
       Predef_Prims       : Entity_Id;
       Prim               : Entity_Id;
@@ -5494,23 +5493,18 @@ package body Exp_Disp is
 
          Collect_Interfaces (Typ, Typ_Ifaces);
 
-         AI := First_Elmt (Typ_Ifaces);
-         while Present (AI) loop
-            Num_Ifaces := Num_Ifaces + 1;
-            Next_Elmt (AI);
-         end loop;
-
-         if Num_Ifaces = 0 then
+         if Is_Empty_Elmt_List (Typ_Ifaces) then
             Iface_Table_Node := Make_Null (Loc);
 
          --  Generate the Interface_Table object
 
          else
             declare
-               TSD_Ifaces_List  : constant List_Id := New_List;
-               Elmt             : Elmt_Id;
-               Offset_To_Top    : Node_Id;
-               Sec_DT_Tag       : Node_Id;
+               Num_Ifaces      : constant Pos := List_Length (Typ_Ifaces);
+               TSD_Ifaces_List : constant List_Id := New_List;
+               Elmt            : Elmt_Id;
+               Offset_To_Top   : Node_Id;
+               Sec_DT_Tag      : Node_Id;
 
                Dummy_Object_Ifaces_List      : Elist_Id := No_Elist;
                Dummy_Object_Ifaces_Comp_List : Elist_Id := No_Elist;
diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
index b1d6efd..b52d9dd 100644
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -14010,22 +14010,16 @@ package body Sem_Ch12 is
          -----------------------
 
          function Formal_Dimensions return Nat is
-            Num   : Nat := 0;
-            Index : Node_Id;
+            Dims : List_Id;
 
          begin
             if Nkind (Def) = N_Constrained_Array_Definition then
-               Index := First (Discrete_Subtype_Definitions (Def));
+               Dims := Discrete_Subtype_Definitions (Def);
             else
-               Index := First (Subtype_Marks (Def));
+               Dims := Subtype_Marks (Def);
             end if;
 
-            while Present (Index) loop
-               Num := Num + 1;
-               Next (Index);
-            end loop;
-
-            return Num;
+            return List_Length (Dims);
          end Formal_Dimensions;
 
       --  Start of processing for Validate_Array_Type_Instance
@@ -18079,7 +18073,6 @@ package body Sem_Ch12 is
                   Get_Attribute_Id (Attribute_Name (Def));
       T       : constant Entity_Id := Entity (Prefix (Def));
       Is_Fun  : constant Boolean := (Ekind (Nam) = E_Function);
-      F       : Entity_Id;
       Num_F   : Nat;
       OK      : Boolean;
 
@@ -18088,12 +18081,7 @@ package body Sem_Ch12 is
          return;
       end if;
 
-      Num_F := 0;
-      F := First_Formal (Nam);
-      while Present (F) loop
-         Num_F := Num_F + 1;
-         Next_Formal (F);
-      end loop;
+      Num_F := Number_Formals (Nam);
 
       case Attr_Id is
          when Attribute_Adjacent
diff --git a/gcc/ada/sem_prag.adb b/gcc/ada/sem_prag.adb
index 50ba96b..081716a 100644
--- a/gcc/ada/sem_prag.adb
+++ b/gcc/ada/sem_prag.adb
@@ -8801,19 +8801,8 @@ package body Sem_Prag is
                   Minimum : constant Nat :=
                     Convention_Id'Pos (C) -
                       Convention_Id'Pos (Convention_C_Variadic_0);
-
-                  Count  : Nat;
-                  Formal : Entity_Id;
-
                begin
-                  Count := 0;
-                  Formal := First_Formal (Subp);
-                  while Present (Formal) loop
-                     Count := Count + 1;
-                     Next_Formal (Formal);
-                  end loop;
-
-                  if Count < Minimum then
+                  if Number_Formals (Subp) < Minimum then
                      Error_Msg_Uint_1 := UI_From_Int (Minimum);
                      Error_Pragma_Arg
                        ("argument of pragma% must have at least"
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 6bc50c4..bd798d7 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -2915,7 +2915,7 @@ package body Sem_Util is
                           Expr_Value (Low_Bound (Aggregate_Bounds (N)))
                then
                   declare
-                     Count_Components   : Uint := Uint_0;
+                     Count_Components   : Uint;
                      Num_Components     : Uint;
                      Others_Assoc       : Node_Id := Empty;
                      Others_Choice      : Node_Id := Empty;
@@ -2924,13 +2924,8 @@ package body Sem_Util is
                   begin
                      --  Count positional associations
 
-                     if Present (Expressions (N)) then
-                        Comp_Expr := First (Expressions (N));
-                        while Present (Comp_Expr) loop
-                           Count_Components := Count_Components + 1;
-                           Next (Comp_Expr);
-                        end loop;
-                     end if;
+                     Count_Components :=
+                       UI_From_Int (List_Length (Expressions (N)));
 
                      --  Count the rest of elements and locate the N_Others
                      --  choice (if any)
@@ -25044,8 +25039,8 @@ package body Sem_Util is
       First_Named : Node_Id := Empty;
       Found       : Boolean;
 
-      Formals_To_Match : Integer := 0;
-      Actuals_To_Match : Integer := 0;
+      Formals_To_Match : Int := 0;
+      Actuals_To_Match : Int := 0;
 
       procedure Chain (A : Node_Id);
       --  Add named actual at the proper place in the list, using the
@@ -25106,16 +25101,11 @@ package body Sem_Util is
          --  The name in the call is a function call that returns an access
          --  to subprogram. The designated type has the list of formals.
 
-         Formal := First_Formal (Designated_Type (S));
+         Formals_To_Match := Number_Formals (Designated_Type (S));
       else
-         Formal := First_Formal (S);
+         Formals_To_Match := Number_Formals (S);
       end if;
 
-      while Present (Formal) loop
-         Formals_To_Match := Formals_To_Match + 1;
-         Next_Formal (Formal);
-      end loop;
-
       --  Find if there is a named association, and verify that no positional
       --  associations appear after named ones.