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diff --git a/gcc/ada/sem_aux.ads b/gcc/ada/sem_aux.ads new file mode 100755 index 000000000..e54016c99 --- /dev/null +++ b/gcc/ada/sem_aux.ads @@ -0,0 +1,225 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S E M _ A U X -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2010, 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. -- +-- -- +-- 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. -- +-- -- +------------------------------------------------------------------------------ + +-- Package containing utility procedures used throughout the compiler, +-- and also by ASIS so dependencies are limited to ASIS included packages. + +-- Historical note. Many of the routines here were originally in Einfo, but +-- Einfo is supposed to be a relatively low level package dealing with the +-- content of entities in the tree, so this package is used for routines that +-- require more than minimal semantic knowledge. + +with Alloc; use Alloc; +with Table; +with Types; use Types; + +package Sem_Aux is + + -------------------------------- + -- Obsolescent Warnings Table -- + -------------------------------- + + -- This table records entities for which a pragma Obsolescent with a + -- message argument has been processed. + + type OWT_Record is record + Ent : Entity_Id; + -- The entity to which the pragma applies + + Msg : String_Id; + -- The string containing the message + end record; + + package Obsolescent_Warnings is new Table.Table ( + Table_Component_Type => OWT_Record, + Table_Index_Type => Int, + Table_Low_Bound => 0, + Table_Initial => Alloc.Obsolescent_Warnings_Initial, + Table_Increment => Alloc.Obsolescent_Warnings_Increment, + Table_Name => "Obsolescent_Warnings"); + + procedure Initialize; + -- Called at the start of compilation of each new main source file to + -- initialize the allocation of the Obsolescent_Warnings table. Note that + -- Initialize must not be called if Tree_Read is used. + + procedure Tree_Read; + -- Initializes Obsolescent_Warnings table from current tree file using the + -- relevant Table.Tree_Read routine. + + procedure Tree_Write; + -- Writes out Obsolescent_Warnings table to current tree file using the + -- relevant Table.Tree_Write routine. + + ----------------- + -- Subprograms -- + ----------------- + + function Ancestor_Subtype (Typ : Entity_Id) return Entity_Id; + -- The argument Id is a type or subtype entity. If the argument is a + -- subtype then it returns the subtype or type from which the subtype was + -- obtained, otherwise it returns Empty. + + function Available_View (Typ : Entity_Id) return Entity_Id; + -- Typ is typically a type that has the With_Type flag set. Returns the + -- non-limited view of the type, if available, otherwise the type itself. + -- For class-wide types, there is no direct link in the tree, so we have + -- to retrieve the class-wide type of the non-limited view of the Etype. + -- Returns the argument unchanged if it is not one of these cases. + + function Constant_Value (Ent : Entity_Id) return Node_Id; + -- Id is a variable, constant, named integer, or named real entity. This + -- call obtains the initialization expression for the entity. Will return + -- Empty for for a deferred constant whose full view is not available or + -- in some other cases of internal entities, which cannot be treated as + -- constants from the point of view of constant folding. Empty is also + -- returned for variables with no initialization expression. + + function Enclosing_Dynamic_Scope (Ent : Entity_Id) return Entity_Id; + -- For any entity, Ent, returns the closest dynamic scope in which the + -- entity is declared or Standard_Standard for library-level entities + + function First_Discriminant (Typ : Entity_Id) return Entity_Id; + -- Typ is a type with discriminants. The discriminants are the first + -- entities declared in the type, so normally this is equivalent to + -- First_Entity. The exception arises for tagged types, where the tag + -- itself is prepended to the front of the entity chain, so the + -- First_Discriminant function steps past the tag if it is present. + + function First_Stored_Discriminant (Typ : Entity_Id) return Entity_Id; + -- Typ is a type with discriminants. Gives the first discriminant stored + -- in an object of this type. In many cases, these are the same as the + -- normal visible discriminants for the type, but in the case of renamed + -- discriminants, this is not always the case. + -- + -- For tagged types, and untagged types which are root types or derived + -- types but which do not rename discriminants in their root type, the + -- stored discriminants are the same as the actual discriminants of the + -- type, and hence this function is the same as First_Discriminant. + -- + -- For derived non-tagged types that rename discriminants in the root type + -- this is the first of the discriminants that occur in the root type. To + -- be precise, in this case stored discriminants are entities attached to + -- the entity chain of the derived type which are a copy of the + -- discriminants of the root type. Furthermore their Is_Completely_Hidden + -- flag is set since although they are actually stored in the object, they + -- are not in the set of discriminants that is visible in the type. + -- + -- For derived untagged types, the set of stored discriminants are the real + -- discriminants from Gigi's standpoint, i.e. those that will be stored in + -- actual objects of the type. + + function First_Subtype (Typ : Entity_Id) return Entity_Id; + -- Applies to all types and subtypes. For types, yields the first subtype + -- of the type. For subtypes, yields the first subtype of the base type of + -- the subtype. + + function First_Tag_Component (Typ : Entity_Id) return Entity_Id; + -- Typ must be a tagged record type. This function returns the Entity for + -- the first _Tag field in the record type. + + function Is_By_Copy_Type (Ent : Entity_Id) return Boolean; + -- Ent is any entity. Returns True if Ent is a type entity where the type + -- is required to be passed by copy, as defined in (RM 6.2(3)). + + function Is_By_Reference_Type (Ent : Entity_Id) return Boolean; + -- Ent is any entity. Returns True if Ent is a type entity where the type + -- is required to be passed by reference, as defined in (RM 6.2(4-9)). + + function Is_Derived_Type (Ent : Entity_Id) return Boolean; + -- Determines if the given entity Ent is a derived type. Result is always + -- false if argument is not a type. + + function Is_Generic_Formal (E : Entity_Id) return Boolean; + -- Determine whether E is a generic formal parameter. In particular this is + -- used to set the visibility of generic formals of a generic package + -- declared with a box or with partial parametrization. + + function Is_Indefinite_Subtype (Ent : Entity_Id) return Boolean; + -- Ent is any entity. Determines if given entity is an unconstrained array + -- type or subtype, a discriminated record type or subtype with no initial + -- discriminant values or a class wide type or subtype and returns True if + -- so. False for other type entities, or any entities that are not types. + + function Is_Immutably_Limited_Type (Ent : Entity_Id) return Boolean; + -- Ent is any entity. True for a type that is "inherently" limited (i.e. + -- cannot become nonlimited). From the Ada 2005 RM-7.5(8.1/2), "a type with + -- a part that is of a task, protected, or explicitly limited record type". + -- These are the types that are defined as return-by-reference types in Ada + -- 95 (see RM95-6.5(11-16)). In Ada 2005, these are the types that require + -- build-in-place for function calls. Note that build-in-place is allowed + -- for other types, too. This is also used for identifying pure procedures + -- whose calls should not be eliminated (RM 10.2.1(18/2)). + + function Is_Limited_Type (Ent : Entity_Id) return Boolean; + -- Ent is any entity. Returns true if Ent is a limited type (limited + -- private type, limited interface type, task type, protected type, + -- composite containing a limited component, or a subtype of any of + -- these types). + + function Nearest_Ancestor (Typ : Entity_Id) return Entity_Id; + -- Given a subtype Typ, this function finds out the nearest ancestor from + -- which constraints and predicates are inherited. There is no simple link + -- for doing this, consider: + -- + -- subtype R is Integer range 1 .. 10; + -- type T is new R; + -- + -- In this case the nearest ancestor is R, but the Etype of T'Base will + -- point to R'Base, so we have to go rummaging in the declarations to get + -- this information. It is used for making sure we freeze this before we + -- freeze Typ, and also for retrieving inherited predicate information. + -- For the case of base types or first subtypes, there is no useful entity + -- to return, so Empty is returned. + -- + -- Note: this is similar to Ancestor_Subtype except that it also deals + -- with the case of derived types. + + function Nearest_Dynamic_Scope (Ent : Entity_Id) return Entity_Id; + -- This is similar to Enclosing_Dynamic_Scope except that if Ent is itself + -- a dynamic scope, then it is returned. Otherwise the result is the same + -- as that returned by Enclosing_Dynamic_Scope. + + function Next_Tag_Component (Tag : Entity_Id) return Entity_Id; + -- Tag must be an entity representing a _Tag field of a tagged record. + -- The result returned is the next _Tag field in this record, or Empty + -- if this is the last such field. + + function Number_Discriminants (Typ : Entity_Id) return Pos; + -- Typ is a type with discriminants, yields number of discriminants in type + + function Ultimate_Alias (Prim : Entity_Id) return Entity_Id; + pragma Inline (Ultimate_Alias); + -- Return the last entity in the chain of aliased entities of Prim. If Prim + -- has no alias return Prim. + +end Sem_Aux; |