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Diffstat (limited to 'gcc/ada/libgnat/s-pack48.adb')
| -rw-r--r-- | gcc/ada/libgnat/s-pack48.adb | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/gcc/ada/libgnat/s-pack48.adb b/gcc/ada/libgnat/s-pack48.adb new file mode 100644 index 0000000..26e3165 --- /dev/null +++ b/gcc/ada/libgnat/s-pack48.adb @@ -0,0 +1,250 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- S Y S T E M . P A C K _ 4 8 -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1992-2017, 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/>. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +with System.Storage_Elements; +with System.Unsigned_Types; + +package body System.Pack_48 is + + subtype Bit_Order is System.Bit_Order; + Reverse_Bit_Order : constant Bit_Order := + Bit_Order'Val (1 - Bit_Order'Pos (System.Default_Bit_Order)); + + 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_48; + 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; + + type Rev_Cluster is new Cluster + with Bit_Order => Reverse_Bit_Order, + Scalar_Storage_Order => Reverse_Bit_Order; + type Rev_Cluster_Ref is access Rev_Cluster; + + -- The following declarations are for the case where the address + -- passed to GetU_48 or SetU_48 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; + + type Rev_ClusterU is new ClusterU + with Bit_Order => Reverse_Bit_Order, + Scalar_Storage_Order => Reverse_Bit_Order; + type Rev_ClusterU_Ref is access Rev_ClusterU; + + ------------ + -- Get_48 -- + ------------ + + function Get_48 + (Arr : System.Address; + N : Natural; + Rev_SSO : Boolean) return Bits_48 + is + A : constant System.Address := Arr + Bits * Ofs (Uns (N) / 8); + C : Cluster_Ref with Address => A'Address, Import; + RC : Rev_Cluster_Ref with Address => A'Address, Import; + begin + if Rev_SSO then + case N07 (Uns (N) mod 8) is + when 0 => return RC.E0; + when 1 => return RC.E1; + when 2 => return RC.E2; + when 3 => return RC.E3; + when 4 => return RC.E4; + when 5 => return RC.E5; + when 6 => return RC.E6; + when 7 => return RC.E7; + end case; + + else + 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 if; + end Get_48; + + ------------- + -- GetU_48 -- + ------------- + + function GetU_48 + (Arr : System.Address; + N : Natural; + Rev_SSO : Boolean) return Bits_48 + is + A : constant System.Address := Arr + Bits * Ofs (Uns (N) / 8); + C : ClusterU_Ref with Address => A'Address, Import; + RC : Rev_ClusterU_Ref with Address => A'Address, Import; + begin + if Rev_SSO then + case N07 (Uns (N) mod 8) is + when 0 => return RC.E0; + when 1 => return RC.E1; + when 2 => return RC.E2; + when 3 => return RC.E3; + when 4 => return RC.E4; + when 5 => return RC.E5; + when 6 => return RC.E6; + when 7 => return RC.E7; + end case; + + else + 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 if; + end GetU_48; + + ------------ + -- Set_48 -- + ------------ + + procedure Set_48 + (Arr : System.Address; + N : Natural; + E : Bits_48; + Rev_SSO : Boolean) + is + A : constant System.Address := Arr + Bits * Ofs (Uns (N) / 8); + C : Cluster_Ref with Address => A'Address, Import; + RC : Rev_Cluster_Ref with Address => A'Address, Import; + begin + if Rev_SSO then + case N07 (Uns (N) mod 8) is + when 0 => RC.E0 := E; + when 1 => RC.E1 := E; + when 2 => RC.E2 := E; + when 3 => RC.E3 := E; + when 4 => RC.E4 := E; + when 5 => RC.E5 := E; + when 6 => RC.E6 := E; + when 7 => RC.E7 := E; + end case; + else + 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 if; + end Set_48; + + ------------- + -- SetU_48 -- + ------------- + + procedure SetU_48 + (Arr : System.Address; + N : Natural; + E : Bits_48; + Rev_SSO : Boolean) + is + A : constant System.Address := Arr + Bits * Ofs (Uns (N) / 8); + C : ClusterU_Ref with Address => A'Address, Import; + RC : Rev_ClusterU_Ref with Address => A'Address, Import; + begin + if Rev_SSO then + case N07 (Uns (N) mod 8) is + when 0 => RC.E0 := E; + when 1 => RC.E1 := E; + when 2 => RC.E2 := E; + when 3 => RC.E3 := E; + when 4 => RC.E4 := E; + when 5 => RC.E5 := E; + when 6 => RC.E6 := E; + when 7 => RC.E7 := E; + end case; + else + 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 if; + end SetU_48; + +end System.Pack_48; |