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Diffstat (limited to 'gcc-4.2.1/gcc/ada/g-table.adb')
| -rw-r--r-- | gcc-4.2.1/gcc/ada/g-table.adb | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/gcc-4.2.1/gcc/ada/g-table.adb b/gcc-4.2.1/gcc/ada/g-table.adb new file mode 100644 index 000000000..4d7a09b21 --- /dev/null +++ b/gcc-4.2.1/gcc/ada/g-table.adb @@ -0,0 +1,260 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- G N A T . T A B L E -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1998-2005, AdaCore -- +-- -- +-- 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, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, 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. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +with System; use System; +with System.Memory; use System.Memory; + +with Unchecked_Conversion; + +package body GNAT.Table is + + Min : constant Integer := Integer (Table_Low_Bound); + -- Subscript of the minimum entry in the currently allocated table + + Max : Integer; + -- Subscript of the maximum entry in the currently allocated table + + Length : Integer := 0; + -- Number of entries in currently allocated table. The value of zero + -- ensures that we initially allocate the table. + + Last_Val : Integer; + -- Current value of Last + + ----------------------- + -- Local Subprograms -- + ----------------------- + + procedure Reallocate; + -- Reallocate the existing table according to the current value stored + -- in Max. Works correctly to do an initial allocation if the table + -- is currently null. + + pragma Warnings (Off); + -- Turn off warnings. The following unchecked conversions are only used + -- internally in this package, and cannot never result in any instances + -- of improperly aliased pointers for the client of the package. + + function To_Address is new Unchecked_Conversion (Table_Ptr, Address); + function To_Pointer is new Unchecked_Conversion (Address, Table_Ptr); + + pragma Warnings (On); + + -------------- + -- Allocate -- + -------------- + + function Allocate (Num : Integer := 1) return Table_Index_Type is + Old_Last : constant Integer := Last_Val; + + begin + Last_Val := Last_Val + Num; + + if Last_Val > Max then + Reallocate; + end if; + + return Table_Index_Type (Old_Last + 1); + end Allocate; + + ------------ + -- Append -- + ------------ + + procedure Append (New_Val : Table_Component_Type) is + begin + Increment_Last; + Table (Table_Index_Type (Last_Val)) := New_Val; + end Append; + + -------------------- + -- Decrement_Last -- + -------------------- + + procedure Decrement_Last is + begin + Last_Val := Last_Val - 1; + end Decrement_Last; + + ---------- + -- Free -- + ---------- + + procedure Free is + begin + Free (To_Address (Table)); + Table := null; + Length := 0; + end Free; + + -------------------- + -- Increment_Last -- + -------------------- + + procedure Increment_Last is + begin + Last_Val := Last_Val + 1; + + if Last_Val > Max then + Reallocate; + end if; + end Increment_Last; + + ---------- + -- Init -- + ---------- + + procedure Init is + Old_Length : constant Integer := Length; + + begin + Last_Val := Min - 1; + Max := Min + Table_Initial - 1; + Length := Max - Min + 1; + + -- If table is same size as before (happens when table is never + -- expanded which is a common case), then simply reuse it. Note + -- that this also means that an explicit Init call right after + -- the implicit one in the package body is harmless. + + if Old_Length = Length then + return; + + -- Otherwise we can use Reallocate to get a table of the right size. + -- Note that Reallocate works fine to allocate a table of the right + -- initial size when it is first allocated. + + else + Reallocate; + end if; + end Init; + + ---------- + -- Last -- + ---------- + + function Last return Table_Index_Type is + begin + return Table_Index_Type (Last_Val); + end Last; + + ---------------- + -- Reallocate -- + ---------------- + + procedure Reallocate is + New_Size : size_t; + + begin + if Max < Last_Val then + pragma Assert (not Locked); + + while Max < Last_Val loop + + -- Increase length using the table increment factor, but make + -- sure that we add at least ten elements (this avoids a loop + -- for silly small increment values) + + Length := Integer'Max + (Length * (100 + Table_Increment) / 100, + Length + 10); + Max := Min + Length - 1; + end loop; + end if; + + New_Size := + size_t ((Max - Min + 1) * + (Table_Type'Component_Size / Storage_Unit)); + + if Table = null then + Table := To_Pointer (Alloc (New_Size)); + + elsif New_Size > 0 then + Table := + To_Pointer (Realloc (Ptr => To_Address (Table), + Size => New_Size)); + end if; + + if Length /= 0 and then Table = null then + raise Storage_Error; + end if; + + end Reallocate; + + ------------- + -- Release -- + ------------- + + procedure Release is + begin + Length := Last_Val - Integer (Table_Low_Bound) + 1; + Max := Last_Val; + Reallocate; + end Release; + + -------------- + -- Set_Item -- + -------------- + + procedure Set_Item + (Index : Table_Index_Type; + Item : Table_Component_Type) + is + begin + if Integer (Index) > Last_Val then + Set_Last (Index); + end if; + + Table (Index) := Item; + end Set_Item; + + -------------- + -- Set_Last -- + -------------- + + procedure Set_Last (New_Val : Table_Index_Type) is + begin + if Integer (New_Val) < Last_Val then + Last_Val := Integer (New_Val); + else + Last_Val := Integer (New_Val); + + if Last_Val > Max then + Reallocate; + end if; + end if; + end Set_Last; + +begin + Init; +end GNAT.Table; |