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) 2002-2009, 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 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. --
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. --
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/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 with System.Address_Operations; use System.Address_Operations;
34 with Ada.Unchecked_Conversion;
36 package body System.Compare_Array_Unsigned_64 is
38 type Word is mod 2 ** 64;
39 -- Used to process operands by words
41 type Uword is new Word;
42 for Uword'Alignment use 1;
43 -- Used to process operands when unaligned
45 type WP is access Word;
46 type UP is access Uword;
48 function W is new Ada.Unchecked_Conversion (Address, WP);
49 function U is new Ada.Unchecked_Conversion (Address, UP);
51 -----------------------
52 -- Compare_Array_U64 --
53 -----------------------
55 function Compare_Array_U64
56 (Left : System.Address;
57 Right : System.Address;
59 Right_Len : Natural) return Integer
61 Clen : Natural := Natural'Min (Left_Len, Right_Len);
62 -- Number of elements left to compare
66 -- Pointers to next elements to compare
69 -- Case of going by aligned double words
71 if ModA (OrA (Left, Right), 8) = 0 then
73 if W (L).all /= W (R).all then
74 if W (L).all > W (R).all then
86 -- Case of going by unaligned double words
90 if U (L).all /= U (R).all then
91 if U (L).all > U (R).all then
104 -- Here if common section equal, result decided by lengths
106 if Left_Len = Right_Len then
108 elsif Left_Len > Right_Len then
113 end Compare_Array_U64;
115 end System.Compare_Array_Unsigned_64;