[19/77] Add a smallest_int_mode_for_size helper function
[official-gcc.git] / gcc / ada / s-widlli.adb
blob4d0aa3a5e92ec965f3d071a252ab917f884bc6b8
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- S Y S T E M . W I D _ L L I --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
17 -- --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
32 package body System.Wid_LLI is
34 -----------------------------
35 -- Width_Long_Long_Integer --
36 -----------------------------
38 function Width_Long_Long_Integer
39 (Lo, Hi : Long_Long_Integer)
40 return Natural
42 W : Natural;
43 T : Long_Long_Integer;
45 begin
46 if Lo > Hi then
47 return 0;
49 else
50 -- Minimum value is 2, one for sign, one for digit
52 W := 2;
54 -- Get max of absolute values, but avoid bomb if we have the maximum
55 -- negative number (note that First + 1 has same digits as First)
57 T := Long_Long_Integer'Max (
58 abs (Long_Long_Integer'Max (Lo, Long_Long_Integer'First + 1)),
59 abs (Long_Long_Integer'Max (Hi, Long_Long_Integer'First + 1)));
61 -- Increase value if more digits required
63 while T >= 10 loop
64 T := T / 10;
65 W := W + 1;
66 end loop;
68 return W;
69 end if;
71 end Width_Long_Long_Integer;
73 end System.Wid_LLI;