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Diffstat (limited to 'gcc/ada/s-pooloc.adb')
| -rw-r--r-- | gcc/ada/s-pooloc.adb | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/gcc/ada/s-pooloc.adb b/gcc/ada/s-pooloc.adb new file mode 100644 index 00000000000..6adbf2d33ca --- /dev/null +++ b/gcc/ada/s-pooloc.adb @@ -0,0 +1,154 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S Y S T E M . P O O L _ L O C A L -- +-- -- +-- B o d y -- +-- -- +-- $Revision: 1.11 $ +-- -- +-- Copyright (C) 1992-2001, 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.Memory; +with System.Storage_Elements; +with System.Address_To_Access_Conversions; + +package body System.Pool_Local is + + package SSE renames System.Storage_Elements; + use type SSE.Storage_Offset; + + Pointer_Size : constant SSE.Storage_Offset := Address'Size / Storage_Unit; + Pointers_Size : constant SSE.Storage_Offset := 2 * Pointer_Size; + + type Acc_Address is access all Address; + package Addr is new Address_To_Access_Conversions (Address); + + ----------------------- + -- Local Subprograms -- + ----------------------- + + function Next (A : Address) return Acc_Address; + -- Given an address of a block, return an access to the next block + + function Prev (A : Address) return Acc_Address; + -- Given an address of a block, return an access to the previous block + + -------------- + -- Allocate -- + -------------- + + procedure Allocate + (Pool : in out Unbounded_Reclaim_Pool; + Address : out System.Address; + Storage_Size : SSE.Storage_Count; + Alignment : SSE.Storage_Count) + is + Allocated : constant System.Address := + Memory.Alloc (Memory.size_t (Storage_Size + Pointers_Size)); + + begin + -- The call to Alloc returns an address whose alignment is compatible + -- with the worst case alignment requirement for the machine; thus the + -- Alignment argument can be safely ignored. + + if Allocated = Null_Address then + raise Storage_Error; + else + Address := Allocated + Pointers_Size; + Next (Allocated).all := Pool.First; + Prev (Allocated).all := Null_Address; + + if Pool.First /= Null_Address then + Prev (Pool.First).all := Allocated; + end if; + + Pool.First := Allocated; + end if; + end Allocate; + + ---------------- + -- Deallocate -- + ---------------- + + procedure Deallocate + (Pool : in out Unbounded_Reclaim_Pool; + Address : System.Address; + Storage_Size : SSE.Storage_Count; + Alignment : SSE.Storage_Count) + is + Allocated : constant System.Address := Address - Pointers_Size; + begin + if Prev (Allocated).all = Null_Address then + Pool.First := Next (Allocated).all; + Prev (Pool.First).all := Null_Address; + else + Next (Prev (Allocated).all).all := Next (Allocated).all; + end if; + + if Next (Allocated).all /= Null_Address then + Prev (Next (Allocated).all).all := Prev (Allocated).all; + end if; + + Memory.Free (Allocated); + end Deallocate; + + -------------- + -- Finalize -- + -------------- + + procedure Finalize (Pool : in out Unbounded_Reclaim_Pool) is + N : System.Address := Pool.First; + Allocated : System.Address; + + begin + while N /= Null_Address loop + Allocated := N; + N := Next (N).all; + Memory.Free (Allocated); + end loop; + end Finalize; + + ---------- + -- Next -- + ---------- + + function Next (A : Address) return Acc_Address is + begin + return Acc_Address (Addr.To_Pointer (A)); + end Next; + + ---------- + -- Prev -- + ---------- + + function Prev (A : Address) return Acc_Address is + begin + return Acc_Address (Addr.To_Pointer (A + Pointer_Size)); + end Prev; + +end System.Pool_Local; |