1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
10 -- Copyright (C) 1992-2001 Free Software Foundation, Inc. --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNAT; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNAT was originally developed by the GNAT team at New York University. --
31 -- Extensive contributions were provided by Ada Core Technologies Inc. --
33 ------------------------------------------------------------------------------
35 with Debug; use Debug;
37 with Output; use Output;
38 pragma Elaborate_All (Output);
39 with System; use System;
40 with Tree_IO; use Tree_IO;
41 with System.Memory; use System.Memory;
42 with System.Address_To_Access_Conversions;
47 Min : constant Int := Int (Table_Low_Bound);
48 -- Subscript of the minimum entry in the currently allocated table
51 -- Number of entries in currently allocated table. The value of zero
52 -- ensures that we initially allocate the table.
54 -----------------------
55 -- Local Subprograms --
56 -----------------------
59 -- Reallocate the existing table according to the current value stored
60 -- in Max. Works correctly to do an initial allocation if the table
63 function Tree_Get_Table_Address return Address;
64 -- Return Null_Address if the table length is zero,
65 -- Table (First)'Address if not.
67 package Table_Conversions is
68 new System.Address_To_Access_Conversions (Big_Table_Type);
69 -- Address and Access conversions for a Table object.
71 function To_Address (Table : Table_Ptr) return Address;
72 pragma Inline (To_Address);
73 -- Returns the Address for the Table object.
75 function To_Pointer (Table : Address) return Table_Ptr;
76 pragma Inline (To_Pointer);
77 -- Returns the Access pointer for the Table object.
83 procedure Append (New_Val : Table_Component_Type) is
86 Table (Table_Index_Type (Last_Val)) := New_Val;
93 procedure Decrement_Last is
95 Last_Val := Last_Val - 1;
104 Free (To_Address (Table));
113 procedure Increment_Last is
115 Last_Val := Last_Val + 1;
117 if Last_Val > Max then
127 Old_Length : Int := Length;
131 Max := Min + (Table_Initial * Opt.Table_Factor) - 1;
132 Length := Max - Min + 1;
134 -- If table is same size as before (happens when table is never
135 -- expanded which is a common case), then simply reuse it. Note
136 -- that this also means that an explicit Init call right after
137 -- the implicit one in the package body is harmless.
139 if Old_Length = Length then
142 -- Otherwise we can use Reallocate to get a table of the right size.
143 -- Note that Reallocate works fine to allocate a table of the right
144 -- initial size when it is first allocated.
155 function Last return Table_Index_Type is
157 return Table_Index_Type (Last_Val);
164 procedure Reallocate is
165 New_Size : Memory.size_t;
168 if Max < Last_Val then
169 pragma Assert (not Locked);
171 -- Make sure that we have at least the initial allocation. This
172 -- is needed in cases where a zero length table is written out.
174 Length := Int'Max (Length, Table_Initial);
176 -- Now increment table length until it is sufficiently large
178 while Max < Last_Val loop
179 Length := Length * (100 + Table_Increment) / 100;
180 Max := Min + Length - 1;
184 Write_Str ("--> Allocating new ");
185 Write_Str (Table_Name);
186 Write_Str (" table, size = ");
187 Write_Int (Max - Min + 1);
193 Memory.size_t ((Max - Min + 1) *
194 (Table_Type'Component_Size / Storage_Unit));
197 Table := To_Pointer (Alloc (New_Size));
199 elsif New_Size > 0 then
201 To_Pointer (Realloc (Ptr => To_Address (Table),
205 if Length /= 0 and then Table = null then
207 Write_Str ("available memory exhausted");
210 raise Unrecoverable_Error;
221 Length := Last_Val - Int (Table_Low_Bound) + 1;
230 procedure Restore (T : Saved_Table) is
232 Free (To_Address (Table));
233 Last_Val := T.Last_Val;
236 Length := Max - Min + 1;
243 function Save return Saved_Table is
247 Res.Last_Val := Last_Val;
262 (Index : Table_Index_Type;
263 Item : Table_Component_Type)
266 if Int (Index) > Max then
270 Table (Index) := Item;
277 procedure Set_Last (New_Val : Table_Index_Type) is
279 if Int (New_Val) < Last_Val then
280 Last_Val := Int (New_Val);
282 Last_Val := Int (New_Val);
284 if Last_Val > Max then
294 function To_Address (Table : Table_Ptr) return Address is
296 return Table_Conversions.To_Address
297 (Table_Conversions.Object_Pointer (Table));
304 function To_Pointer (Table : Address) return Table_Ptr is
306 return Table_Ptr (Table_Conversions.To_Pointer (Table));
309 ----------------------------
310 -- Tree_Get_Table_Address --
311 ----------------------------
313 function Tree_Get_Table_Address return Address is
318 return Table (First)'Address;
320 end Tree_Get_Table_Address;
326 -- Note: we allocate only the space required to accommodate the data
327 -- actually written, which means that a Tree_Write/Tree_Read sequence
328 -- does an implicit Release.
330 procedure Tree_Read is
334 Length := Max - Min + 1;
338 (Tree_Get_Table_Address,
339 (Last_Val - Int (First) + 1) *
340 Table_Type'Component_Size / Storage_Unit);
347 -- Note: we write out only the currently valid data, not the entire
348 -- contents of the allocated array. See note above on Tree_Read.
350 procedure Tree_Write is
352 Tree_Write_Int (Int (Last));
354 (Tree_Get_Table_Address,
355 (Last_Val - Int (First) + 1) *
356 Table_Type'Component_Size / Storage_Unit);