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Diffstat (limited to 'gcc-4.4.0/gcc/ada/exp_tss.ads')
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diff --git a/gcc-4.4.0/gcc/ada/exp_tss.ads b/gcc-4.4.0/gcc/ada/exp_tss.ads new file mode 100644 index 000000000..e72e38cc2 --- /dev/null +++ b/gcc-4.4.0/gcc/ada/exp_tss.ads @@ -0,0 +1,229 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- E X P _ T S S -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2008, 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 3, 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 COPYING3. If not, go to -- +-- http://www.gnu.org/licenses for a complete copy of the license. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- Type Support Subprogram (TSS) handling + +with Namet; use Namet; +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. + + ------------------------- + -- Current Limitations -- + ------------------------- + + -- In the current version of this package, only the case of generating a + -- TSS at the point of declaration of the type is accommodated. A clear + -- improvement would be to follow through with the full implementation + -- as described above, and also accommodate the requirement of generating + -- only one copy in a given object file. + + -- For now, we deal with the local case by generating duplicate versions + -- of the TSS routine, which is clearly rather inefficient in space usage. + -- This is done by using Make_TSS_Name_Local to generate unique names + -- for the different instances of TSS routines in a given scope. + + ---------------- + -- TSS Naming -- + ---------------- + + -- A TSS is identified by its Chars name. The name has the form typXY or + -- typ_<serial>XY, where typ is the type name, and XY are two characters + -- that identify the particular TSS routine. A unique serial number is + -- included for the case where several local instances of the same TSS + -- must be generated (see discussion under Make_TSS_Name_Local). + + -- The following codes are used to denote TSSs: + + -- Note: When making additions to this list, update the list in snames.adb + + type TSS_Name_Type is new String (1 .. 2); + subtype TNT is TSS_Name_Type; + + TSS_Deep_Adjust : constant TNT := "DA"; -- Deep Adjust + TSS_Deep_Finalize : constant TNT := "DF"; -- Deep Finalize + TSS_Deep_Initialize : constant TNT := "DI"; -- Deep Initialize + TSS_Composite_Equality : constant TNT := "EQ"; -- Composite Equality + TSS_From_Any : constant TNT := "FA"; -- PolyORB/DSA From_Any + TSS_Init_Proc : constant TNT := "IP"; -- Initialization Procedure + TSS_RAS_Access : constant TNT := "RA"; -- RAS type access + TSS_RAS_Dereference : constant TNT := "RD"; -- RAS type deference + TSS_Rep_To_Pos : constant TNT := "RP"; -- Rep to Pos conversion + TSS_Slice_Assign : constant TNT := "SA"; -- Slice assignment + TSS_Stream_Input : constant TNT := "SI"; -- Stream Input attribute + TSS_Stream_Output : constant TNT := "SO"; -- Stream Output attribute + TSS_Stream_Read : constant TNT := "SR"; -- Stream Read attribute + TSS_Stream_Write : constant TNT := "SW"; -- Stream Write attribute + TSS_To_Any : constant TNT := "TA"; -- PolyORB/DSA To_Any + TSS_TypeCode : constant TNT := "TC"; -- PolyORB/DSA TypeCode + + -- The array below contains all valid TSS names + + TSS_Names : constant array (Natural range <>) of TSS_Name_Type := + (TSS_Deep_Adjust, + TSS_Deep_Finalize, + TSS_Deep_Initialize, + TSS_Composite_Equality, + TSS_From_Any, + TSS_Init_Proc, + TSS_RAS_Access, + TSS_RAS_Dereference, + TSS_Rep_To_Pos, + TSS_Slice_Assign, + TSS_Stream_Input, + TSS_Stream_Output, + TSS_Stream_Read, + TSS_Stream_Write, + TSS_To_Any, + TSS_TypeCode); + + TSS_Null : constant TNT := " "; + -- Dummy entry used to indicated that this is not really a TSS + + function Get_TSS_Name (E : Entity_Id) return TSS_Name_Type; + -- Given an entity, if it is a TSS, then return the corresponding TSS + -- name type, otherwise return TSS_Null. + + function Make_TSS_Name + (Typ : Entity_Id; + Nam : TSS_Name_Type) return Name_Id; + -- Construct the name as described above for the given TSS routine + -- identified by Nam for the type identified by Typ. + + function Make_TSS_Name_Local + (Typ : Entity_Id; + Nam : TSS_Name_Type) return Name_Id; + -- Similar to the above call, but a string of the form _nnn is inserted + -- before the TSS code suffix, where nnn is a unique serial number. This + -- is used when multiple instances of the same TSS routine may be + -- generated in the same scope (see also discussion above of current + -- limitations). + + function Make_Init_Proc_Name (Typ : Entity_Id) return Name_Id; + -- Version for init procs, same as Make_TSS_Name (Typ, TSS_Init_Proc) + + function Is_TSS (E : Entity_Id; Nam : TSS_Name_Type) return Boolean; + -- Determines if given entity (E) is the name of a TSS identified by Nam + + function Is_TSS (N : Name_Id; Nam : TSS_Name_Type) return Boolean; + -- Same test applied directly to a Name_Id value + + function Is_Init_Proc (E : Entity_Id) return Boolean; + -- Version for init procs, same as Is_TSS (E, TSS_Init_Proc); + + ----------------------------------------- + -- TSS Data structures and Subprograms -- + ----------------------------------------- + + -- 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 : TSS_Name_Type) return Entity_Id; + -- Finds the TSS with the given name associated with the given type + -- If no such TSS exists, then Empty is returned; + + 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. + + function Same_TSS (E1, E2 : Entity_Id) return Boolean; + -- Returns True if E1 and E2 are the same kind of TSS, even if the names + -- are different (i.e. if the names of E1 and E2 end with two upper case + -- letters that are the same). + + 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 + -- 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 proc TSS, but initialization is required. The init proc used is + -- the one for 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. + + function Find_Inherited_TSS + (Typ : Entity_Id; + Nam : TSS_Name_Type) return Entity_Id; + -- Returns the TSS of name Nam of Typ, or of its closest ancestor defining + -- such a TSS. Empty is returned is neither Typ nor any of its ancestors + -- have such a TSS. + +end Exp_Tss; |