1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- G N A T . D Y N A M I C _ T A B L E S --
9 -- Copyright (C) 2000-2001 Ada Core Technologies, 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 is maintained by Ada Core Technologies Inc (http://www.gnat.com). --
31 ------------------------------------------------------------------------------
33 with System; use System;
34 with System.Memory; use System.Memory;
35 with System.Address_To_Access_Conversions;
37 package body GNAT.Dynamic_Tables is
39 Min : constant Integer := Integer (Table_Low_Bound);
40 -- Subscript of the minimum entry in the currently allocated table
42 -----------------------
43 -- Local Subprograms --
44 -----------------------
46 procedure Reallocate (T : in out Instance);
47 -- Reallocate the existing table according to the current value stored
48 -- in Max. Works correctly to do an initial allocation if the table
51 package Table_Conversions is
52 new System.Address_To_Access_Conversions (Big_Table_Type);
53 -- Address and Access conversions for a Table object.
55 function To_Address (Table : Table_Ptr) return Address;
56 pragma Inline (To_Address);
57 -- Returns the Address for the Table object.
59 function To_Pointer (Table : Address) return Table_Ptr;
60 pragma Inline (To_Pointer);
61 -- Returns the Access pointer for the Table object.
72 T.P.Last_Val := T.P.Last_Val + Num;
74 if T.P.Last_Val > T.P.Max then
83 procedure Append (T : in out Instance; New_Val : Table_Component_Type) is
86 T.Table (Table_Index_Type (T.P.Last_Val)) := New_Val;
93 procedure Decrement_Last (T : in out Instance) is
95 T.P.Last_Val := T.P.Last_Val - 1;
102 procedure Free (T : in out Instance) is
104 Free (To_Address (T.Table));
113 procedure Increment_Last (T : in out Instance) is
115 T.P.Last_Val := T.P.Last_Val + 1;
117 if T.P.Last_Val > T.P.Max then
126 procedure Init (T : in out Instance) is
127 Old_Length : constant Integer := T.P.Length;
130 T.P.Last_Val := Min - 1;
131 T.P.Max := Min + Table_Initial - 1;
132 T.P.Length := T.P.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 = T.P.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 (T : in Instance) return Table_Index_Type is
157 return Table_Index_Type (T.P.Last_Val);
164 procedure Reallocate (T : in out Instance) is
168 if T.P.Max < T.P.Last_Val then
169 while T.P.Max < T.P.Last_Val loop
170 T.P.Length := T.P.Length * (100 + Table_Increment) / 100;
171 T.P.Max := Min + T.P.Length - 1;
176 size_t ((T.P.Max - Min + 1) *
177 (Table_Type'Component_Size / Storage_Unit));
179 if T.Table = null then
180 T.Table := To_Pointer (Alloc (New_Size));
182 elsif New_Size > 0 then
184 To_Pointer (Realloc (Ptr => To_Address (T.Table),
188 if T.P.Length /= 0 and then T.Table = null then
198 procedure Release (T : in out Instance) is
200 T.P.Length := T.P.Last_Val - Integer (Table_Low_Bound) + 1;
201 T.P.Max := T.P.Last_Val;
210 (T : in out Instance;
211 Index : Table_Index_Type;
212 Item : Table_Component_Type)
215 if Integer (Index) > T.P.Max then
219 T.Table (Index) := Item;
226 procedure Set_Last (T : in out Instance; New_Val : Table_Index_Type) is
228 if Integer (New_Val) < T.P.Last_Val then
229 T.P.Last_Val := Integer (New_Val);
232 T.P.Last_Val := Integer (New_Val);
234 if T.P.Last_Val > T.P.Max then
244 function To_Address (Table : Table_Ptr) return Address is
246 return Table_Conversions.To_Address
247 (Table_Conversions.Object_Pointer (Table));
254 function To_Pointer (Table : Address) return Table_Ptr is
256 return Table_Ptr (Table_Conversions.To_Pointer (Table));
259 end GNAT.Dynamic_Tables;