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Diffstat (limited to 'gcc-4.4.0/gcc/ada/a-szbzha.adb')
-rw-r--r-- | gcc-4.4.0/gcc/ada/a-szbzha.adb | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/gcc-4.4.0/gcc/ada/a-szbzha.adb b/gcc-4.4.0/gcc/ada/a-szbzha.adb new file mode 100644 index 000000000..48e272746 --- /dev/null +++ b/gcc-4.4.0/gcc/ada/a-szbzha.adb @@ -0,0 +1,53 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT LIBRARY COMPONENTS -- +-- -- +-- ADA.STRINGS.WIDE_WIDE_BOUNDED.WIDE_WIDE_HASH -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 2004-2009, Free Software Foundation, Inc. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 3, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- You should have received a copy of the GNU General Public License and -- +-- a copy of the GCC Runtime Library Exception along with this program; -- +-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- +-- <http://www.gnu.org/licenses/>. -- +-- -- +-- This unit was originally developed by Matthew J Heaney. -- +------------------------------------------------------------------------------ + +-- Note: source of this algorithm: GNAT.HTable.Hash (g-htable.adb) + +function Ada.Strings.Wide_Wide_Bounded.Wide_Wide_Hash + (Key : Bounded.Bounded_Wide_Wide_String) + return Containers.Hash_Type +is + use Ada.Containers; + + function Rotate_Left + (Value : Hash_Type; + Amount : Natural) return Hash_Type; + pragma Import (Intrinsic, Rotate_Left); + + Tmp : Hash_Type; + +begin + Tmp := 0; + for J in 1 .. Bounded.Length (Key) loop + Tmp := Rotate_Left (Tmp, 3) + + Wide_Wide_Character'Pos (Bounded.Element (Key, J)); + end loop; + + return Tmp; +end Ada.Strings.Wide_Wide_Bounded.Wide_Wide_Hash; |