Daily bump.
[official-gcc.git] / gcc / ada / s-pack19.adb
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- S Y S T E M . P A C K _ 1 9 --
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 with System.Storage_Elements;
33 with System.Unsigned_Types;
34 with Ada.Unchecked_Conversion;
36 package body System.Pack_19 is
38 subtype Ofs is System.Storage_Elements.Storage_Offset;
39 subtype Uns is System.Unsigned_Types.Unsigned;
40 subtype N07 is System.Unsigned_Types.Unsigned range 0 .. 7;
42 use type System.Storage_Elements.Storage_Offset;
43 use type System.Unsigned_Types.Unsigned;
45 type Cluster is record
46 E0, E1, E2, E3, E4, E5, E6, E7 : Bits_19;
47 end record;
49 for Cluster use record
50 E0 at 0 range 0 * Bits .. 0 * Bits + Bits - 1;
51 E1 at 0 range 1 * Bits .. 1 * Bits + Bits - 1;
52 E2 at 0 range 2 * Bits .. 2 * Bits + Bits - 1;
53 E3 at 0 range 3 * Bits .. 3 * Bits + Bits - 1;
54 E4 at 0 range 4 * Bits .. 4 * Bits + Bits - 1;
55 E5 at 0 range 5 * Bits .. 5 * Bits + Bits - 1;
56 E6 at 0 range 6 * Bits .. 6 * Bits + Bits - 1;
57 E7 at 0 range 7 * Bits .. 7 * Bits + Bits - 1;
58 end record;
60 for Cluster'Size use Bits * 8;
62 for Cluster'Alignment use Integer'Min (Standard'Maximum_Alignment,
63 1 +
64 1 * Boolean'Pos (Bits mod 2 = 0) +
65 2 * Boolean'Pos (Bits mod 4 = 0));
66 -- Use maximum possible alignment, given the bit field size, since this
67 -- will result in the most efficient code possible for the field.
69 type Cluster_Ref is access Cluster;
71 function To_Ref is new
72 Ada.Unchecked_Conversion (System.Address, Cluster_Ref);
74 ------------
75 -- Get_19 --
76 ------------
78 function Get_19 (Arr : System.Address; N : Natural) return Bits_19 is
79 C : constant Cluster_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8));
80 begin
81 case N07 (Uns (N) mod 8) is
82 when 0 => return C.E0;
83 when 1 => return C.E1;
84 when 2 => return C.E2;
85 when 3 => return C.E3;
86 when 4 => return C.E4;
87 when 5 => return C.E5;
88 when 6 => return C.E6;
89 when 7 => return C.E7;
90 end case;
91 end Get_19;
93 ------------
94 -- Set_19 --
95 ------------
97 procedure Set_19 (Arr : System.Address; N : Natural; E : Bits_19) is
98 C : constant Cluster_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8));
99 begin
100 case N07 (Uns (N) mod 8) is
101 when 0 => C.E0 := E;
102 when 1 => C.E1 := E;
103 when 2 => C.E2 := E;
104 when 3 => C.E3 := E;
105 when 4 => C.E4 := E;
106 when 5 => C.E5 := E;
107 when 6 => C.E6 := E;
108 when 7 => C.E7 := E;
109 end case;
110 end Set_19;
112 end System.Pack_19;