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diff --git a/gcc-4.3.1/gcc/ada/g-table.ads b/gcc-4.3.1/gcc/ada/g-table.ads new file mode 100644 index 000000000..ae64b8589 --- /dev/null +++ b/gcc-4.3.1/gcc/ada/g-table.ads @@ -0,0 +1,201 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- G N A T . T A B L E -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1998-2007, 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. -- +-- -- +------------------------------------------------------------------------------ + +-- Resizable one dimensional array support + +-- This package provides an implementation of dynamically resizable one +-- dimensional arrays. The idea is to mimic the normal Ada semantics for +-- arrays as closely as possible with the one additional capability of +-- dynamically modifying the value of the Last attribute. + +-- This package provides a facility similar to that of GNAT.Dynamic_Tables, +-- except that this package declares a single instance of the table type, +-- while an instantiation of GNAT.Dynamic_Tables creates a type that can be +-- used to define dynamic instances of the table. + +-- Note that this interface should remain synchronized with those in +-- GNAT.Dynamic_Tables and the GNAT compiler source unit Table to keep +-- as much coherency as possible between these three related units. + +generic + type Table_Component_Type is private; + type Table_Index_Type is range <>; + + Table_Low_Bound : Table_Index_Type; + Table_Initial : Positive; + Table_Increment : Natural; + +package GNAT.Table is + pragma Elaborate_Body; + + -- Table_Component_Type and Table_Index_Type specify the type of the + -- array, Table_Low_Bound is the lower bound. Index_type must be an + -- integer type. The effect is roughly to declare: + + -- Table : array (Table_Index_Type range Table_Low_Bound .. <>) + -- of Table_Component_Type; + + -- Note: since the upper bound can be one less than the lower + -- bound for an empty array, the table index type must be able + -- to cover this range, e.g. if the lower bound is 1, then the + -- Table_Index_Type should be Natural rather than Positive. + + -- Table_Component_Type may be any Ada type, except that controlled + -- types are not supported. Note however that default initialization + -- will NOT occur for array components. + + -- The Table_Initial values controls the allocation of the table when + -- it is first allocated, either by default, or by an explicit Init call. + + -- The Table_Increment value controls the amount of increase, if the + -- table has to be increased in size. The value given is a percentage + -- value (e.g. 100 = increase table size by 100%, i.e. double it). + + -- The Last and Set_Last subprograms provide control over the current + -- logical allocation. They are quite efficient, so they can be used + -- freely (expensive reallocation occurs only at major granularity + -- chunks controlled by the allocation parameters). + + -- Note: we do not make the table components aliased, since this would + -- restrict the use of table for discriminated types. If it is necessary + -- to take the access of a table element, use Unrestricted_Access. + + -- WARNING: On HPPA, the virtual addressing approach used in this unit + -- is incompatible with the indexing instructions on the HPPA. So when + -- using this unit, compile your application with -mdisable-indexing. + + -- WARNING: If the table is reallocated, then the address of all its + -- components will change. So do not capture the address of an element + -- and then use the address later after the table may be reallocated. + -- One tricky case of this is passing an element of the table to a + -- subprogram by reference where the table gets reallocated during + -- the execution of the subprogram. The best rule to follow is never + -- to pass a table element as a parameter except for the case of IN + -- mode parameters with scalar values. + + type Table_Type is + array (Table_Index_Type range <>) of Table_Component_Type; + + subtype Big_Table_Type is + Table_Type (Table_Low_Bound .. Table_Index_Type'Last); + -- We work with pointers to a bogus array type that is constrained + -- with the maximum possible range bound. This means that the pointer + -- is a thin pointer, which is more efficient. Since subscript checks + -- in any case must be on the logical, rather than physical bounds, + -- safety is not compromised by this approach. + + type Table_Ptr is access all Big_Table_Type; + -- The table is actually represented as a pointer to allow reallocation + + Table : aliased Table_Ptr := null; + -- The table itself. The lower bound is the value of Low_Bound. + -- Logically the upper bound is the current value of Last (although + -- the actual size of the allocated table may be larger than this). + -- The program may only access and modify Table entries in the range + -- First .. Last. + + Locked : Boolean := False; + -- Table expansion is permitted only if this switch is set to False. A + -- client may set Locked to True, in which case any attempt to expand + -- the table will cause an assertion failure. Note that while a table + -- is locked, its address in memory remains fixed and unchanging. + + procedure Init; + -- This procedure allocates a new table of size Initial (freeing any + -- previously allocated larger table). It is not necessary to call + -- Init when a table is first instantiated (since the instantiation does + -- the same initialization steps). However, it is harmless to do so, and + -- Init is convenient in reestablishing a table for new use. + + function Last return Table_Index_Type; + pragma Inline (Last); + -- Returns the current value of the last used entry in the table, which + -- can then be used as a subscript for Table. Note that the only way to + -- modify Last is to call the Set_Last procedure. Last must always be + -- used to determine the logically last entry. + + procedure Release; + -- Storage is allocated in chunks according to the values given in the + -- Initial and Increment parameters. A call to Release releases all + -- storage that is allocated, but is not logically part of the current + -- array value. Current array values are not affected by this call. + + procedure Free; + -- Free all allocated memory for the table. A call to Init is required + -- before any use of this table after calling Free. + + First : constant Table_Index_Type := Table_Low_Bound; + -- Export First as synonym for Low_Bound (parallel with use of Last) + + procedure Set_Last (New_Val : Table_Index_Type); + pragma Inline (Set_Last); + -- This procedure sets Last to the indicated value. If necessary the + -- table is reallocated to accommodate the new value (i.e. on return + -- the allocated table has an upper bound of at least Last). If Set_Last + -- reduces the size of the table, then logically entries are removed + -- from the table. If Set_Last increases the size of the table, then + -- new entries are logically added to the table. + + procedure Increment_Last; + pragma Inline (Increment_Last); + -- Adds 1 to Last (same as Set_Last (Last + 1) + + procedure Decrement_Last; + pragma Inline (Decrement_Last); + -- Subtracts 1 from Last (same as Set_Last (Last - 1) + + procedure Append (New_Val : Table_Component_Type); + pragma Inline (Append); + -- Equivalent to: + -- x.Increment_Last; + -- x.Table (x.Last) := New_Val; + -- i.e. the table size is increased by one, and the given new item + -- stored in the newly created table element. + + procedure Set_Item + (Index : Table_Index_Type; + Item : Table_Component_Type); + pragma Inline (Set_Item); + -- Put Item in the table at position Index. The table is expanded if the + -- current table length is less than Index and in that case Last is set to + -- Index. Item will replace any value already present in the table at this + -- position. + + function Allocate (Num : Integer := 1) return Table_Index_Type; + pragma Inline (Allocate); + -- Adds Num to Last, and returns the old value of Last + 1. Note that + -- this function has the possible side effect of reallocating the table. + -- This means that a reference X.Table (X.Allocate) is incorrect, since + -- the call to X.Allocate may modify the results of calling X.Table. + +end GNAT.Table; |