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diff --git a/gcc/ada/exp_tss.ads b/gcc/ada/exp_tss.ads new file mode 100644 index 00000000000..1df084fed88 --- /dev/null +++ b/gcc/ada/exp_tss.ads @@ -0,0 +1,112 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- E X P _ T S S -- +-- -- +-- S p e c -- +-- -- +-- $Revision: 1.7 $ +-- -- +-- Copyright (C) 1992-2001 Free Software Foundation, Inc. -- +-- -- +-- 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, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, USA. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +-- Type Support Subprogram (TSS) handling + +with Types; use Types; + +package Exp_Tss is + + -- A type support subprogram (TSS) is an internally generated function or + -- procedure that is associated with a particular type. Examples are the + -- implicit initialization procedure, and subprograms for the Input and + -- Output attributes. + + -- A given TSS is either generated once at the point of the declaration of + -- the type, or it is generated as needed in clients, but only one copy is + -- required in any one generated object file. The choice between these two + -- possibilities is made on a TSS-by-TSS basis depending on the estimation + -- of how likely the TSS is to be used. Initialization procedures fall in + -- the first category, for example, since it is likely that any declared + -- type will be used in a context requiring initialization, but the stream + -- attributes use the second approach, since it is more likely that they + -- will not be used at all, or will only be used in one client in any case. + + -- A TSS is identified by its Chars name, i.e. for a given TSS type, the + -- same name is used for all types, e.g. the initialization routine has + -- the name _init for all types. + + -- The TSS's for a given type are stored in an element list associated with + -- the type, and referenced from the TSS_Elist field of the N_Freeze_Entity + -- node associated with the type (all types that need TSS's always need to + -- be explicitly frozen, so the N_Freeze_Entity node always exists). + + function TSS (Typ : Entity_Id; Nam : Name_Id) return Entity_Id; + -- Finds the TSS with the given name associated with the given type. If + -- no such TSS exists, then Empty is returned. + + procedure Set_TSS (Typ : Entity_Id; TSS : Entity_Id); + -- This procedure is used to install a newly created TSS. The second + -- argument is the entity for such a new TSS. This entity is placed in + -- the TSS list for the type given as the first argument, replacing an + -- old entry of the same name if one was present. The tree for the body + -- of this TSS, which is not analyzed yet, is placed in the actions field + -- of the freeze node for the type. All such bodies are inserted into the + -- main tree and analyzed at the point at which the freeze node itself is + -- is expanded. + + procedure Copy_TSS (TSS : Entity_Id; Typ : Entity_Id); + -- Given an existing TSS for another type (which is already installed, + -- analyzed and expanded), install it as the corresponding TSS for Typ. + -- Note that this just copies a reference, not the tree. This can also + -- be used to initially install a TSS in the case where the subprogram + -- for the TSS has already been created and its declaration processed. + + function Init_Proc (Typ : Entity_Id) return Entity_Id; + pragma Inline (Init_Proc); + -- Obtains the _init TSS entry for the given type. This function call is + -- equivalent to TSS (Typ, Name_uInit). The _init TSS is the procedure + -- used to initialize otherwise uninitialized instances of a type. If + -- there is no _init TSS, then the type requires no initialization. Note + -- that subtypes and implicit types never have an _init TSS since subtype + -- objects are always initialized using the initialization procedure for + -- the corresponding base type (see Base_Init_Proc function). A special + -- case arises for concurrent types. Such types do not themselves have an + -- _init TSR, but initialization is required. The initialization procedure + -- used is the one fot the corresponding record type (see Base_Init_Proc). + + function Base_Init_Proc (Typ : Entity_Id) return Entity_Id; + -- Obtains the _Init TSS entry from the base type of the entity, and also + -- deals with going indirect through the Corresponding_Record_Type field + -- for concurrent objects (which are initialized with the initialization + -- routine for the corresponding record type). Returns Empty if there is + -- no _Init TSS entry for the base type. + + procedure Set_Init_Proc (Typ : Entity_Id; Init : Entity_Id); + pragma Inline (Set_Init_Proc); + -- The second argument is the _init TSS to be established for the type + -- given as the first argument. Equivalent to Set_TSS (Typ, Init). + + function Has_Non_Null_Base_Init_Proc (Typ : Entity_Id) return Boolean; + -- Returns true if the given type has a defined Base_Init_Proc and + -- this init proc is not a null init proc (null init procs occur as + -- a result of the processing for Initialize_Scalars. This function + -- is used to test for the presence of an Init_Proc in cases where + -- a null init proc is considered equivalent to no Init_Proc. + +end Exp_Tss; |