1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2001 Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 with Debug; use Debug;
36 with Output; use Output;
37 pragma Elaborate_All (Output);
38 with System; use System;
39 with Tree_IO; use Tree_IO;
40 with System.Memory; use System.Memory;
41 with System.Address_To_Access_Conversions;
46 Min : constant Int := Int (Table_Low_Bound);
47 -- Subscript of the minimum entry in the currently allocated table
50 -- Number of entries in currently allocated table. The value of zero
51 -- ensures that we initially allocate the table.
53 -----------------------
54 -- Local Subprograms --
55 -----------------------
58 -- Reallocate the existing table according to the current value stored
59 -- in Max. Works correctly to do an initial allocation if the table
62 function Tree_Get_Table_Address return Address;
63 -- Return Null_Address if the table length is zero,
64 -- Table (First)'Address if not.
66 package Table_Conversions is
67 new System.Address_To_Access_Conversions (Big_Table_Type);
68 -- Address and Access conversions for a Table object.
70 function To_Address (Table : Table_Ptr) return Address;
71 pragma Inline (To_Address);
72 -- Returns the Address for the Table object.
74 function To_Pointer (Table : Address) return Table_Ptr;
75 pragma Inline (To_Pointer);
76 -- Returns the Access pointer for the Table object.
82 procedure Append (New_Val : Table_Component_Type) is
85 Table (Table_Index_Type (Last_Val)) := New_Val;
92 procedure Decrement_Last is
94 Last_Val := Last_Val - 1;
103 Free (To_Address (Table));
112 procedure Increment_Last is
114 Last_Val := Last_Val + 1;
116 if Last_Val > Max then
126 Old_Length : Int := Length;
130 Max := Min + (Table_Initial * Opt.Table_Factor) - 1;
131 Length := Max - Min + 1;
133 -- If table is same size as before (happens when table is never
134 -- expanded which is a common case), then simply reuse it. Note
135 -- that this also means that an explicit Init call right after
136 -- the implicit one in the package body is harmless.
138 if Old_Length = Length then
141 -- Otherwise we can use Reallocate to get a table of the right size.
142 -- Note that Reallocate works fine to allocate a table of the right
143 -- initial size when it is first allocated.
154 function Last return Table_Index_Type is
156 return Table_Index_Type (Last_Val);
163 procedure Reallocate is
164 New_Size : Memory.size_t;
167 if Max < Last_Val then
168 pragma Assert (not Locked);
170 -- Make sure that we have at least the initial allocation. This
171 -- is needed in cases where a zero length table is written out.
173 Length := Int'Max (Length, Table_Initial);
175 -- Now increment table length until it is sufficiently large
177 while Max < Last_Val loop
178 Length := Length * (100 + Table_Increment) / 100;
179 Max := Min + Length - 1;
183 Write_Str ("--> Allocating new ");
184 Write_Str (Table_Name);
185 Write_Str (" table, size = ");
186 Write_Int (Max - Min + 1);
192 Memory.size_t ((Max - Min + 1) *
193 (Table_Type'Component_Size / Storage_Unit));
196 Table := To_Pointer (Alloc (New_Size));
198 elsif New_Size > 0 then
200 To_Pointer (Realloc (Ptr => To_Address (Table),
204 if Length /= 0 and then Table = null then
206 Write_Str ("available memory exhausted");
209 raise Unrecoverable_Error;
220 Length := Last_Val - Int (Table_Low_Bound) + 1;
229 procedure Restore (T : Saved_Table) is
231 Free (To_Address (Table));
232 Last_Val := T.Last_Val;
235 Length := Max - Min + 1;
242 function Save return Saved_Table is
246 Res.Last_Val := Last_Val;
261 (Index : Table_Index_Type;
262 Item : Table_Component_Type)
265 if Int (Index) > Max then
269 Table (Index) := Item;
276 procedure Set_Last (New_Val : Table_Index_Type) is
278 if Int (New_Val) < Last_Val then
279 Last_Val := Int (New_Val);
281 Last_Val := Int (New_Val);
283 if Last_Val > Max then
293 function To_Address (Table : Table_Ptr) return Address is
295 return Table_Conversions.To_Address
296 (Table_Conversions.Object_Pointer (Table));
303 function To_Pointer (Table : Address) return Table_Ptr is
305 return Table_Ptr (Table_Conversions.To_Pointer (Table));
308 ----------------------------
309 -- Tree_Get_Table_Address --
310 ----------------------------
312 function Tree_Get_Table_Address return Address is
317 return Table (First)'Address;
319 end Tree_Get_Table_Address;
325 -- Note: we allocate only the space required to accommodate the data
326 -- actually written, which means that a Tree_Write/Tree_Read sequence
327 -- does an implicit Release.
329 procedure Tree_Read is
333 Length := Max - Min + 1;
337 (Tree_Get_Table_Address,
338 (Last_Val - Int (First) + 1) *
339 Table_Type'Component_Size / Storage_Unit);
346 -- Note: we write out only the currently valid data, not the entire
347 -- contents of the allocated array. See note above on Tree_Read.
349 procedure Tree_Write is
351 Tree_Write_Int (Int (Last));
353 (Tree_Get_Table_Address,
354 (Last_Val - Int (First) + 1) *
355 Table_Type'Component_Size / Storage_Unit);