1------------------------------------------------------------------------------ 2-- -- 3-- GNU ADA RUNTIME LIBRARY COMPONENTS -- 4-- -- 5-- S Y S T E M . C O M P A R E _ A R R A Y _ S I G N E D _ 6 4 -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 2002 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 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, 59 Temple Place - Suite 330, Boston, -- 20-- MA 02111-1307, USA. -- 21-- -- 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. -- 28-- -- 29-- GNAT was originally developed by the GNAT team at New York University. -- 30-- Extensive contributions were provided by Ada Core Technologies Inc. -- 31-- -- 32------------------------------------------------------------------------------ 33 34with Unchecked_Conversion; 35 36package body System.Compare_Array_Signed_64 is 37 38 type Word is range -2**63 .. 2**63 - 1; 39 for Word'Size use 64; 40 -- Used to process operands by words 41 42 type Uword is record 43 W : Word; 44 end record; 45 pragma Pack (Uword); 46 for Uword'Alignment use 1; 47 -- Used to process operands when unaligned 48 49 type WP is access Word; 50 type UP is access Uword; 51 52 function W is new Unchecked_Conversion (Address, WP); 53 function U is new Unchecked_Conversion (Address, UP); 54 55 ----------------------- 56 -- Compare_Array_S64 -- 57 ----------------------- 58 59 function Compare_Array_S64 60 (Left : System.Address; 61 Right : System.Address; 62 Left_Len : Natural; 63 Right_Len : Natural) 64 return Integer 65 is 66 Clen : Natural := Natural'Min (Left_Len, Right_Len); 67 -- Number of elements left to compare 68 69 L : Address := Left; 70 R : Address := Right; 71 -- Pointers to next elements to compare 72 73 begin 74 -- Case of going by aligned words 75 76 if ((Left or Right) and (8 - 1)) = 0 then 77 while Clen /= 0 loop 78 if W (L).all /= W (R).all then 79 if W (L).all > W (R).all then 80 return +1; 81 else 82 return -1; 83 end if; 84 end if; 85 86 Clen := Clen - 1; 87 L := L + 8; 88 R := R + 8; 89 end loop; 90 91 -- Case of going by unaligned words 92 93 else 94 while Clen /= 0 loop 95 if U (L).W /= U (R).W then 96 if U (L).W > U (R).W then 97 return +1; 98 else 99 return -1; 100 end if; 101 end if; 102 103 Clen := Clen - 1; 104 L := L + 8; 105 R := R + 8; 106 end loop; 107 end if; 108 109 -- Here if common section equal, result decided by lengths 110 111 if Left_Len = Right_Len then 112 return 0; 113 elsif Left_Len > Right_Len then 114 return +1; 115 else 116 return -1; 117 end if; 118 end Compare_Array_S64; 119 120end System.Compare_Array_Signed_64; 121