1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- G N A T . D Y N A M I C _ T A B L E S --
10 -- Copyright (C) 2000-2001 Ada Core Technologies, 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 is maintained by Ada Core Technologies Inc (http://www.gnat.com). --
32 ------------------------------------------------------------------------------
34 with System; use System;
35 with System.Memory; use System.Memory;
36 with System.Address_To_Access_Conversions;
38 package body GNAT.Dynamic_Tables is
40 Min : constant Integer := Integer (Table_Low_Bound);
41 -- Subscript of the minimum entry in the currently allocated table
43 -----------------------
44 -- Local Subprograms --
45 -----------------------
47 procedure Reallocate (T : in out Instance);
48 -- Reallocate the existing table according to the current value stored
49 -- in Max. Works correctly to do an initial allocation if the table
52 package Table_Conversions is
53 new System.Address_To_Access_Conversions (Big_Table_Type);
54 -- Address and Access conversions for a Table object.
56 function To_Address (Table : Table_Ptr) return Address;
57 pragma Inline (To_Address);
58 -- Returns the Address for the Table object.
60 function To_Pointer (Table : Address) return Table_Ptr;
61 pragma Inline (To_Pointer);
62 -- Returns the Access pointer for the Table object.
73 T.P.Last_Val := T.P.Last_Val + Num;
75 if T.P.Last_Val > T.P.Max then
84 procedure Append (T : in out Instance; New_Val : Table_Component_Type) is
87 T.Table (Table_Index_Type (T.P.Last_Val)) := New_Val;
94 procedure Decrement_Last (T : in out Instance) is
96 T.P.Last_Val := T.P.Last_Val - 1;
103 procedure Free (T : in out Instance) is
105 Free (To_Address (T.Table));
114 procedure Increment_Last (T : in out Instance) is
116 T.P.Last_Val := T.P.Last_Val + 1;
118 if T.P.Last_Val > T.P.Max then
127 procedure Init (T : in out Instance) is
128 Old_Length : constant Integer := T.P.Length;
131 T.P.Last_Val := Min - 1;
132 T.P.Max := Min + Table_Initial - 1;
133 T.P.Length := T.P.Max - Min + 1;
135 -- If table is same size as before (happens when table is never
136 -- expanded which is a common case), then simply reuse it. Note
137 -- that this also means that an explicit Init call right after
138 -- the implicit one in the package body is harmless.
140 if Old_Length = T.P.Length then
143 -- Otherwise we can use Reallocate to get a table of the right size.
144 -- Note that Reallocate works fine to allocate a table of the right
145 -- initial size when it is first allocated.
156 function Last (T : in Instance) return Table_Index_Type is
158 return Table_Index_Type (T.P.Last_Val);
165 procedure Reallocate (T : in out Instance) is
169 if T.P.Max < T.P.Last_Val then
170 while T.P.Max < T.P.Last_Val loop
171 T.P.Length := T.P.Length * (100 + Table_Increment) / 100;
172 T.P.Max := Min + T.P.Length - 1;
177 size_t ((T.P.Max - Min + 1) *
178 (Table_Type'Component_Size / Storage_Unit));
180 if T.Table = null then
181 T.Table := To_Pointer (Alloc (New_Size));
183 elsif New_Size > 0 then
185 To_Pointer (Realloc (Ptr => To_Address (T.Table),
189 if T.P.Length /= 0 and then T.Table = null then
199 procedure Release (T : in out Instance) is
201 T.P.Length := T.P.Last_Val - Integer (Table_Low_Bound) + 1;
202 T.P.Max := T.P.Last_Val;
211 (T : in out Instance;
212 Index : Table_Index_Type;
213 Item : Table_Component_Type)
216 if Integer (Index) > T.P.Max then
220 T.Table (Index) := Item;
227 procedure Set_Last (T : in out Instance; New_Val : Table_Index_Type) is
229 if Integer (New_Val) < T.P.Last_Val then
230 T.P.Last_Val := Integer (New_Val);
233 T.P.Last_Val := Integer (New_Val);
235 if T.P.Last_Val > T.P.Max then
245 function To_Address (Table : Table_Ptr) return Address is
247 return Table_Conversions.To_Address
248 (Table_Conversions.Object_Pointer (Table));
255 function To_Pointer (Table : Address) return Table_Ptr is
257 return Table_Ptr (Table_Conversions.To_Pointer (Table));
260 end GNAT.Dynamic_Tables;