1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY COMPONENTS --
5 -- S Y S T E M . C O M P A R E _ A R R A Y _ U N S I G N E D _ 6 4 --
9 -- Copyright (C) 2002-2008, Free Software Foundation, Inc. --
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 2, 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 with System.Address_Operations; use System.Address_Operations;
36 with Ada.Unchecked_Conversion;
38 package body System.Compare_Array_Unsigned_64 is
40 type Word is mod 2 ** 64;
41 -- Used to process operands by words
43 type Uword is new Word;
44 for Uword'Alignment use 1;
45 -- Used to process operands when unaligned
47 type WP is access Word;
48 type UP is access Uword;
50 function W is new Ada.Unchecked_Conversion (Address, WP);
51 function U is new Ada.Unchecked_Conversion (Address, UP);
53 -----------------------
54 -- Compare_Array_U64 --
55 -----------------------
57 function Compare_Array_U64
58 (Left : System.Address;
59 Right : System.Address;
61 Right_Len : Natural) return Integer
63 Clen : Natural := Natural'Min (Left_Len, Right_Len);
64 -- Number of elements left to compare
68 -- Pointers to next elements to compare
71 -- Case of going by aligned double words
73 if ModA (OrA (Left, Right), 8) = 0 then
75 if W (L).all /= W (R).all then
76 if W (L).all > W (R).all then
88 -- Case of going by unaligned double words
92 if U (L).all /= U (R).all then
93 if U (L).all > U (R).all then
106 -- Here if common section equal, result decided by lengths
108 if Left_Len = Right_Len then
110 elsif Left_Len > Right_Len then
115 end Compare_Array_U64;
117 end System.Compare_Array_Unsigned_64;