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Diffstat (limited to 'gcc/ada/s-pack54.adb')
| -rw-r--r-- | gcc/ada/s-pack54.adb | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/gcc/ada/s-pack54.adb b/gcc/ada/s-pack54.adb new file mode 100644 index 00000000000..d389e399954 --- /dev/null +++ b/gcc/ada/s-pack54.adb @@ -0,0 +1,171 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUNTIME COMPONENTS -- +-- -- +-- S Y S T E M . P A C K _ 5 4 -- +-- -- +-- B o d y -- +-- -- +-- $Revision: 1.2 $ +-- -- +-- Copyright (C) 1992-1999 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 2, 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. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +with System.Storage_Elements; +with System.Unsigned_Types; +with Unchecked_Conversion; + +package body System.Pack_54 is + + subtype Ofs is System.Storage_Elements.Storage_Offset; + subtype Uns is System.Unsigned_Types.Unsigned; + subtype N07 is System.Unsigned_Types.Unsigned range 0 .. 7; + + use type System.Storage_Elements.Storage_Offset; + use type System.Unsigned_Types.Unsigned; + + type Cluster is record + E0, E1, E2, E3, E4, E5, E6, E7 : Bits_54; + end record; + + for Cluster use record + E0 at 0 range 0 * Bits .. 0 * Bits + Bits - 1; + E1 at 0 range 1 * Bits .. 1 * Bits + Bits - 1; + E2 at 0 range 2 * Bits .. 2 * Bits + Bits - 1; + E3 at 0 range 3 * Bits .. 3 * Bits + Bits - 1; + E4 at 0 range 4 * Bits .. 4 * Bits + Bits - 1; + E5 at 0 range 5 * Bits .. 5 * Bits + Bits - 1; + E6 at 0 range 6 * Bits .. 6 * Bits + Bits - 1; + E7 at 0 range 7 * Bits .. 7 * Bits + Bits - 1; + end record; + + for Cluster'Size use Bits * 8; + + for Cluster'Alignment use Integer'Min (Standard'Maximum_Alignment, + 1 + + 1 * Boolean'Pos (Bits mod 2 = 0) + + 2 * Boolean'Pos (Bits mod 4 = 0)); + -- Use maximum possible alignment, given the bit field size, since this + -- will result in the most efficient code possible for the field. + + type Cluster_Ref is access Cluster; + + function To_Ref is new + Unchecked_Conversion (System.Address, Cluster_Ref); + + -- The following declarations are for the case where the address + -- passed to GetU_54 or SetU_54 is not guaranteed to be aligned. + -- These routines are used when the packed array is itself a + -- component of a packed record, and therefore may not be aligned. + + type ClusterU is new Cluster; + for ClusterU'Alignment use 1; + + type ClusterU_Ref is access ClusterU; + + function To_Ref is new + Unchecked_Conversion (System.Address, ClusterU_Ref); + + ------------ + -- Get_54 -- + ------------ + + function Get_54 (Arr : System.Address; N : Natural) return Bits_54 is + C : constant Cluster_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8)); + + begin + case N07 (Uns (N) mod 8) is + when 0 => return C.E0; + when 1 => return C.E1; + when 2 => return C.E2; + when 3 => return C.E3; + when 4 => return C.E4; + when 5 => return C.E5; + when 6 => return C.E6; + when 7 => return C.E7; + end case; + end Get_54; + + ------------- + -- GetU_54 -- + ------------- + + function GetU_54 (Arr : System.Address; N : Natural) return Bits_54 is + C : constant ClusterU_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8)); + + begin + case N07 (Uns (N) mod 8) is + when 0 => return C.E0; + when 1 => return C.E1; + when 2 => return C.E2; + when 3 => return C.E3; + when 4 => return C.E4; + when 5 => return C.E5; + when 6 => return C.E6; + when 7 => return C.E7; + end case; + end GetU_54; + + ------------ + -- Set_54 -- + ------------ + + procedure Set_54 (Arr : System.Address; N : Natural; E : Bits_54) is + C : constant Cluster_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8)); + + begin + case N07 (Uns (N) mod 8) is + when 0 => C.E0 := E; + when 1 => C.E1 := E; + when 2 => C.E2 := E; + when 3 => C.E3 := E; + when 4 => C.E4 := E; + when 5 => C.E5 := E; + when 6 => C.E6 := E; + when 7 => C.E7 := E; + end case; + end Set_54; + + ------------- + -- SetU_54 -- + ------------- + + procedure SetU_54 (Arr : System.Address; N : Natural; E : Bits_54) is + C : constant ClusterU_Ref := To_Ref (Arr + Bits * Ofs (Uns (N) / 8)); + + begin + case N07 (Uns (N) mod 8) is + when 0 => C.E0 := E; + when 1 => C.E1 := E; + when 2 => C.E2 := E; + when 3 => C.E3 := E; + when 4 => C.E4 := E; + when 5 => C.E5 := E; + when 6 => C.E6 := E; + when 7 => C.E7 := E; + end case; + end SetU_54; + +end System.Pack_54; |