1-- { dg-do compile }
2-- { dg-options "-O3" }
3
4with Opt18_Pkg; use Opt18_Pkg;
5
6package body Opt18 is
7
8   function Mag (Item : in Cart_Vector_Type) return Float is
9   begin
10      return Sqrt (Item (X) * Item (X) + Item (Y) * Item (Y)
11                   + Item (Z) * Item (Z));
12   end;
13
14   function Unit_Quaternion_To_Mag_Axis (Quaternion : in Unit_Quaternion_Type)
15   return Mag_Axis_Type is
16      Sin_Half : Float
17         := Mag (Cart_Vector_Type'(Quaternion.X, Quaternion.Y, Quaternion.Z));
18   begin
19      if Sin_Half > 3.0 * First_Order_Trig then
20         return
21            (Mag  => Atan2 (Double_Trig (Unchecked_Trig_Pair (Sin_Half,
22                                                              Quaternion.S))),
23             Axis => Unit_Vector_Type'(Quaternion.X / Sin_Half,
24                                       Quaternion.Y / Sin_Half,
25                                       Quaternion.Z / Sin_Half));
26      else
27         return (0.0, X_Unit);
28      end if;
29   end;
30
31end Opt18;
32