1------------------------------------------------------------------------------ 2-- -- 3-- GNAT RUN-TIME COMPONENTS -- 4-- -- 5-- G N A T . B Y T E _ S W A P P I N G -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 2006-2018, AdaCore -- 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------------------------------------------------------------------------------ 31 32-- This is a general implementation that uses GCC intrinsics to take 33-- advantage of any machine-specific instructions. 34 35with Ada.Unchecked_Conversion; use Ada; 36 37with System.Byte_Swapping; use System.Byte_Swapping; 38 39package body GNAT.Byte_Swapping is 40 41 -------------- 42 -- Swapped2 -- 43 -------------- 44 45 function Swapped2 (Input : Item) return Item is 46 function As_U16 is new Unchecked_Conversion (Item, U16); 47 function As_Item is new Unchecked_Conversion (U16, Item); 48 pragma Compile_Time_Error (Item'Max_Size_In_Storage_Elements /= 2, 49 "storage size must be 2 bytes"); 50 begin 51 return As_Item (Bswap_16 (As_U16 (Input))); 52 end Swapped2; 53 54 -------------- 55 -- Swapped4 -- 56 -------------- 57 58 function Swapped4 (Input : Item) return Item is 59 function As_U32 is new Unchecked_Conversion (Item, U32); 60 function As_Item is new Unchecked_Conversion (U32, Item); 61 pragma Compile_Time_Error (Item'Max_Size_In_Storage_Elements /= 4, 62 "storage size must be 4 bytes"); 63 begin 64 return As_Item (Bswap_32 (As_U32 (Input))); 65 end Swapped4; 66 67 -------------- 68 -- Swapped8 -- 69 -------------- 70 71 function Swapped8 (Input : Item) return Item is 72 function As_U64 is new Unchecked_Conversion (Item, U64); 73 function As_Item is new Unchecked_Conversion (U64, Item); 74 pragma Compile_Time_Error (Item'Max_Size_In_Storage_Elements /= 8, 75 "storage size must be 8 bytes"); 76 begin 77 return As_Item (Bswap_64 (As_U64 (Input))); 78 end Swapped8; 79 80 ----------- 81 -- Swap2 -- 82 ----------- 83 84 procedure Swap2 (Location : System.Address) is 85 X : U16; 86 for X'Address use Location; 87 begin 88 X := Bswap_16 (X); 89 end Swap2; 90 91 ----------- 92 -- Swap4 -- 93 ----------- 94 95 procedure Swap4 (Location : System.Address) is 96 X : U32; 97 for X'Address use Location; 98 begin 99 X := Bswap_32 (X); 100 end Swap4; 101 102 ----------- 103 -- Swap8 -- 104 ----------- 105 106 procedure Swap8 (Location : System.Address) is 107 X : U64; 108 for X'Address use Location; 109 begin 110 X := Bswap_64 (X); 111 end Swap8; 112 113end GNAT.Byte_Swapping; 114