+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- E X P _ A T T R --
--- --
--- B o d y --
--- --
--- $Revision: 1.2.10.1 $
--- --
--- 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. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
-with Atree; use Atree;
-with Checks; use Checks;
-with Einfo; use Einfo;
-with Exp_Ch2; use Exp_Ch2;
-with Exp_Ch9; use Exp_Ch9;
-with Exp_Imgv; use Exp_Imgv;
-with Exp_Pakd; use Exp_Pakd;
-with Exp_Strm; use Exp_Strm;
-with Exp_Tss; use Exp_Tss;
-with Exp_Util; use Exp_Util;
-with Gnatvsn; use Gnatvsn;
-with Hostparm; use Hostparm;
-with Lib; use Lib;
-with Namet; use Namet;
-with Nmake; use Nmake;
-with Nlists; use Nlists;
-with Opt; use Opt;
-with Restrict; use Restrict;
-with Rtsfind; use Rtsfind;
-with Sem; use Sem;
-with Sem_Ch7; use Sem_Ch7;
-with Sem_Ch8; use Sem_Ch8;
-with Sem_Ch13; use Sem_Ch13;
-with Sem_Eval; use Sem_Eval;
-with Sem_Res; use Sem_Res;
-with Sem_Util; use Sem_Util;
-with Sinfo; use Sinfo;
-with Snames; use Snames;
-with Stand; use Stand;
-with Stringt; use Stringt;
-with Tbuild; use Tbuild;
-with Ttypes; use Ttypes;
-with Uintp; use Uintp;
-with Uname; use Uname;
-with Validsw; use Validsw;
-
-package body Exp_Attr is
-
- -----------------------
- -- Local Subprograms --
- -----------------------
-
- procedure Compile_Stream_Body_In_Scope
- (N : Node_Id;
- Decl : Node_Id;
- Arr : Entity_Id;
- Check : Boolean);
- -- The body for a stream subprogram may be generated outside of the scope
- -- of the type. If the type is fully private, it may depend on the full
- -- view of other types (e.g. indices) that are currently private as well.
- -- We install the declarations of the package in which the type is declared
- -- before compiling the body in what is its proper environment. The Check
- -- parameter indicates if checks are to be suppressed for the stream body.
- -- We suppress checks for array/record reads, since the rule is that these
- -- are like assignments, out of range values due to uninitialized storage,
- -- or other invalid values do NOT cause a Constraint_Error to be raised.
-
- procedure Expand_Fpt_Attribute
- (N : Node_Id;
- Rtp : Entity_Id;
- Args : List_Id);
- -- This procedure expands a call to a floating-point attribute function.
- -- N is the attribute reference node, and Args is a list of arguments to
- -- be passed to the function call. Rtp is the root type of the floating
- -- point type involved (used to select the proper generic instantiation
- -- of the package containing the attribute routines).
-
- procedure Expand_Fpt_Attribute_R (N : Node_Id);
- -- This procedure expands a call to a floating-point attribute function
- -- that takes a single floating-point argument.
-
- procedure Expand_Fpt_Attribute_RI (N : Node_Id);
- -- This procedure expands a call to a floating-point attribute function
- -- that takes one floating-point argument and one integer argument.
-
- procedure Expand_Fpt_Attribute_RR (N : Node_Id);
- -- This procedure expands a call to a floating-point attribute function
- -- that takes two floating-point arguments.
-
- procedure Expand_Pred_Succ (N : Node_Id);
- -- Handles expansion of Pred or Succ attributes for case of non-real
- -- operand with overflow checking required.
-
- function Get_Index_Subtype (N : Node_Id) return Entity_Id;
- -- Used for Last, Last, and Length, when the prefix is an array type,
- -- Obtains the corresponding index subtype.
-
- procedure Expand_Access_To_Type (N : Node_Id);
- -- A reference to a type within its own scope is resolved to a reference
- -- to the current instance of the type in its initialization procedure.
-
- function Find_Inherited_TSS
- (Typ : Entity_Id;
- Nam : Name_Id) return Entity_Id;
-
- function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
- -- Utility for array attributes, returns true on packed constrained
- -- arrays, and on access to same.
-
- ----------------------------------
- -- Compile_Stream_Body_In_Scope --
- ----------------------------------
-
- procedure Compile_Stream_Body_In_Scope
- (N : Node_Id;
- Decl : Node_Id;
- Arr : Entity_Id;
- Check : Boolean)
- is
- Installed : Boolean := False;
- Scop : constant Entity_Id := Scope (Arr);
- Curr : constant Entity_Id := Current_Scope;
-
- begin
- if Is_Hidden (Arr)
- and then not In_Open_Scopes (Scop)
- and then Ekind (Scop) = E_Package
- then
- New_Scope (Scop);
- Install_Visible_Declarations (Scop);
- Install_Private_Declarations (Scop);
- Installed := True;
-
- -- The entities in the package are now visible, but the generated
- -- stream entity must appear in the current scope (usually an
- -- enclosing stream function) so that itypes all have their proper
- -- scopes.
-
- New_Scope (Curr);
- end if;
-
- if Check then
- Insert_Action (N, Decl);
- else
- Insert_Action (N, Decl, All_Checks);
- end if;
-
- if Installed then
-
- -- Remove extra copy of current scope, and package itself
-
- Pop_Scope;
- End_Package_Scope (Scop);
- end if;
- end Compile_Stream_Body_In_Scope;
-
- ---------------------------
- -- Expand_Access_To_Type --
- ---------------------------
-
- procedure Expand_Access_To_Type (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Typ : constant Entity_Id := Etype (N);
- Pref : constant Node_Id := Prefix (N);
- Par : Node_Id;
- Formal : Entity_Id;
-
- begin
- if Is_Entity_Name (Pref)
- and then Is_Type (Entity (Pref))
- then
- -- If the current instance name denotes a task type,
- -- then the access attribute is rewritten to be the
- -- name of the "_task" parameter associated with the
- -- task type's task body procedure. An unchecked
- -- conversion is applied to ensure a type match in
- -- cases of expander-generated calls (e.g., init procs).
-
- if Is_Task_Type (Entity (Pref)) then
- Formal :=
- First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
-
- while Present (Formal) loop
- exit when Chars (Formal) = Name_uTask;
- Next_Entity (Formal);
- end loop;
-
- pragma Assert (Present (Formal));
-
- Rewrite (N,
- Unchecked_Convert_To (Typ, New_Occurrence_Of (Formal, Loc)));
- Set_Etype (N, Typ);
-
- -- The expression must appear in a default expression,
- -- (which in the initialization procedure is the rhs of
- -- an assignment), and not in a discriminant constraint.
-
- else
- Par := Parent (N);
-
- while Present (Par) loop
- exit when Nkind (Par) = N_Assignment_Statement;
-
- if Nkind (Par) = N_Component_Declaration then
- return;
- end if;
-
- Par := Parent (Par);
- end loop;
-
- if Present (Par) then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => Make_Identifier (Loc, Name_uInit),
- Attribute_Name => Attribute_Name (N)));
-
- Analyze_And_Resolve (N, Typ);
- end if;
- end if;
- end if;
- end Expand_Access_To_Type;
-
- --------------------------
- -- Expand_Fpt_Attribute --
- --------------------------
-
- procedure Expand_Fpt_Attribute
- (N : Node_Id;
- Rtp : Entity_Id;
- Args : List_Id)
- is
- Loc : constant Source_Ptr := Sloc (N);
- Typ : constant Entity_Id := Etype (N);
- Pkg : RE_Id;
- Fnm : Node_Id;
-
- begin
- -- The function name is the selected component Fat_xxx.yyy where xxx
- -- is the floating-point root type, and yyy is the attribute name
-
- -- Note: it would be more usual to have separate RE entries for each
- -- of the entities in the Fat packages, but first they have identical
- -- names (so we would have to have lots of renaming declarations to
- -- meet the normal RE rule of separate names for all runtime entities),
- -- and second there would be an awful lot of them!
-
- if Rtp = Standard_Short_Float then
- Pkg := RE_Fat_Short_Float;
- elsif Rtp = Standard_Float then
- Pkg := RE_Fat_Float;
- elsif Rtp = Standard_Long_Float then
- Pkg := RE_Fat_Long_Float;
- else
- Pkg := RE_Fat_Long_Long_Float;
- end if;
-
- Fnm :=
- Make_Selected_Component (Loc,
- Prefix => New_Reference_To (RTE (Pkg), Loc),
- Selector_Name => Make_Identifier (Loc, Attribute_Name (N)));
-
- -- The generated call is given the provided set of parameters, and then
- -- wrapped in a conversion which converts the result to the target type
-
- Rewrite (N,
- Unchecked_Convert_To (Etype (N),
- Make_Function_Call (Loc,
- Name => Fnm,
- Parameter_Associations => Args)));
-
- Analyze_And_Resolve (N, Typ);
-
- end Expand_Fpt_Attribute;
-
- ----------------------------
- -- Expand_Fpt_Attribute_R --
- ----------------------------
-
- -- The single argument is converted to its root type to call the
- -- appropriate runtime function, with the actual call being built
- -- by Expand_Fpt_Attribute
-
- procedure Expand_Fpt_Attribute_R (N : Node_Id) is
- E1 : constant Node_Id := First (Expressions (N));
- Rtp : constant Entity_Id := Root_Type (Etype (E1));
-
- begin
- Expand_Fpt_Attribute (N, Rtp, New_List (
- Unchecked_Convert_To (Rtp, Relocate_Node (E1))));
- end Expand_Fpt_Attribute_R;
-
- -----------------------------
- -- Expand_Fpt_Attribute_RI --
- -----------------------------
-
- -- The first argument is converted to its root type and the second
- -- argument is converted to standard long long integer to call the
- -- appropriate runtime function, with the actual call being built
- -- by Expand_Fpt_Attribute
-
- procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
- E1 : constant Node_Id := First (Expressions (N));
- Rtp : constant Entity_Id := Root_Type (Etype (E1));
- E2 : constant Node_Id := Next (E1);
-
- begin
- Expand_Fpt_Attribute (N, Rtp, New_List (
- Unchecked_Convert_To (Rtp, Relocate_Node (E1)),
- Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
- end Expand_Fpt_Attribute_RI;
-
- -----------------------------
- -- Expand_Fpt_Attribute_RR --
- -----------------------------
-
- -- The two arguments is converted to their root types to call the
- -- appropriate runtime function, with the actual call being built
- -- by Expand_Fpt_Attribute
-
- procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
- E1 : constant Node_Id := First (Expressions (N));
- Rtp : constant Entity_Id := Root_Type (Etype (E1));
- E2 : constant Node_Id := Next (E1);
-
- begin
- Expand_Fpt_Attribute (N, Rtp, New_List (
- Unchecked_Convert_To (Rtp, Relocate_Node (E1)),
- Unchecked_Convert_To (Rtp, Relocate_Node (E2))));
- end Expand_Fpt_Attribute_RR;
-
- ----------------------------------
- -- Expand_N_Attribute_Reference --
- ----------------------------------
-
- procedure Expand_N_Attribute_Reference (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Typ : constant Entity_Id := Etype (N);
- Btyp : constant Entity_Id := Base_Type (Typ);
- Pref : constant Node_Id := Prefix (N);
- Exprs : constant List_Id := Expressions (N);
- Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
-
- procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
- -- Rewrites a stream attribute for Read, Write or Output with the
- -- procedure call. Pname is the entity for the procedure to call.
-
- ------------------------------
- -- Rewrite_Stream_Proc_Call --
- ------------------------------
-
- procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
- Item : constant Node_Id := Next (First (Exprs));
- Formal_Typ : constant Entity_Id :=
- Etype (Next_Formal (First_Formal (Pname)));
-
- begin
- -- We have to worry about the type of the second argument
-
- -- For the class-wide dispatching cases, and for cases in which
- -- the base type of the second argument matches the base type of
- -- the corresponding formal parameter, we are all set, and can use
- -- the argument unchanged.
-
- -- For all other cases we do an unchecked conversion of the second
- -- parameter to the type of the formal of the procedure we are
- -- calling. This deals with the private type cases, and with going
- -- to the root type as required in elementary type case.
-
- if not Is_Class_Wide_Type (Entity (Pref))
- and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
- then
- Rewrite (Item,
- Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
-
- -- For untagged derived types set Assignment_OK, to prevent
- -- copies from being created when the unchecked conversion
- -- is expanded (which would happen in Remove_Side_Effects
- -- if Expand_N_Unchecked_Conversion were allowed to call
- -- Force_Evaluation). The copy could violate Ada semantics
- -- in cases such as an actual that is an out parameter.
- -- Note that this approach is also used in exp_ch7 for calls
- -- to controlled type operations to prevent problems with
- -- actuals wrapped in unchecked conversions.
-
- if Is_Untagged_Derivation (Etype (Expression (Item))) then
- Set_Assignment_OK (Item);
- end if;
- end if;
-
- -- And now rewrite the call
-
- Rewrite (N,
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (Pname, Loc),
- Parameter_Associations => Exprs));
-
- Analyze (N);
- end Rewrite_Stream_Proc_Call;
-
- -- Start of processing for Expand_N_Attribute_Reference
-
- begin
- -- Do required validity checking
-
- if Validity_Checks_On and Validity_Check_Operands then
- declare
- Expr : Node_Id;
-
- begin
- Expr := First (Expressions (N));
- while Present (Expr) loop
- Ensure_Valid (Expr);
- Next (Expr);
- end loop;
- end;
- end if;
-
- -- Remaining processing depends on specific attribute
-
- case Id is
-
- ------------
- -- Access --
- ------------
-
- when Attribute_Access =>
-
- if Ekind (Btyp) = E_Access_Protected_Subprogram_Type then
-
- -- The value of the attribute_reference is a record containing
- -- two fields: an access to the protected object, and an access
- -- to the subprogram itself. The prefix is a selected component.
-
- declare
- Agg : Node_Id;
- Sub : Entity_Id;
- E_T : constant Entity_Id := Equivalent_Type (Typ);
- Acc : constant Entity_Id :=
- Etype (Next_Component (First_Component (E_T)));
- Obj_Ref : Node_Id;
- Curr : Entity_Id;
-
- begin
- -- Within the body of the protected type, the prefix
- -- designates a local operation, and the object is the first
- -- parameter of the corresponding protected body of the
- -- current enclosing operation.
-
- if Is_Entity_Name (Pref) then
- pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
- Sub :=
- New_Occurrence_Of
- (Protected_Body_Subprogram (Entity (Pref)), Loc);
- Curr := Current_Scope;
-
- while Scope (Curr) /= Scope (Entity (Pref)) loop
- Curr := Scope (Curr);
- end loop;
-
- Obj_Ref :=
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of
- (First_Formal
- (Protected_Body_Subprogram (Curr)), Loc),
- Attribute_Name => Name_Address);
-
- -- Case where the prefix is not an entity name. Find the
- -- version of the protected operation to be called from
- -- outside the protected object.
-
- else
- Sub :=
- New_Occurrence_Of
- (External_Subprogram
- (Entity (Selector_Name (Pref))), Loc);
-
- Obj_Ref :=
- Make_Attribute_Reference (Loc,
- Prefix => Relocate_Node (Prefix (Pref)),
- Attribute_Name => Name_Address);
- end if;
-
- Agg :=
- Make_Aggregate (Loc,
- Expressions =>
- New_List (
- Obj_Ref,
- Unchecked_Convert_To (Acc,
- Make_Attribute_Reference (Loc,
- Prefix => Sub,
- Attribute_Name => Name_Address))));
-
- Rewrite (N, Agg);
-
- Analyze_And_Resolve (N, Equivalent_Type (Typ));
-
- -- For subsequent analysis, the node must retain its type.
- -- The backend will replace it with the equivalent type where
- -- needed.
-
- Set_Etype (N, Typ);
- end;
-
- elsif Ekind (Btyp) = E_General_Access_Type then
- declare
- Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
- Parm_Ent : Entity_Id;
- Conversion : Node_Id;
-
- begin
- -- If the prefix of an Access attribute is a dereference of an
- -- access parameter (or a renaming of such a dereference) and
- -- the context is a general access type (but not an anonymous
- -- access type), then rewrite the attribute as a conversion of
- -- the access parameter to the context access type. This will
- -- result in an accessibility check being performed, if needed.
-
- -- (X.all'Access => Acc_Type (X))
-
- if Nkind (Ref_Object) = N_Explicit_Dereference
- and then Is_Entity_Name (Prefix (Ref_Object))
- then
- Parm_Ent := Entity (Prefix (Ref_Object));
-
- if Ekind (Parm_Ent) in Formal_Kind
- and then Ekind (Etype (Parm_Ent)) = E_Anonymous_Access_Type
- and then Present (Extra_Accessibility (Parm_Ent))
- then
- Conversion :=
- Convert_To (Typ, New_Copy_Tree (Prefix (Ref_Object)));
-
- Rewrite (N, Conversion);
- Analyze_And_Resolve (N, Typ);
- end if;
- end if;
- end;
-
- -- If the prefix is a type name, this is a reference to the current
- -- instance of the type, within its initialization procedure.
-
- else
- Expand_Access_To_Type (N);
- end if;
-
- --------------
- -- Adjacent --
- --------------
-
- -- Transforms 'Adjacent into a call to the floating-point attribute
- -- function Adjacent in Fat_xxx (where xxx is the root type)
-
- when Attribute_Adjacent =>
- Expand_Fpt_Attribute_RR (N);
-
- -------------
- -- Address --
- -------------
-
- when Attribute_Address => Address : declare
- Task_Proc : Entity_Id;
-
- begin
- -- If the prefix is a task or a task type, the useful address
- -- is that of the procedure for the task body, i.e. the actual
- -- program unit. We replace the original entity with that of
- -- the procedure.
-
- if Is_Entity_Name (Pref)
- and then Is_Task_Type (Entity (Pref))
- then
- Task_Proc := Next_Entity (Root_Type (Etype (Pref)));
-
- while Present (Task_Proc) loop
- exit when Ekind (Task_Proc) = E_Procedure
- and then Etype (First_Formal (Task_Proc)) =
- Corresponding_Record_Type (Etype (Pref));
- Next_Entity (Task_Proc);
- end loop;
-
- if Present (Task_Proc) then
- Set_Entity (Pref, Task_Proc);
- Set_Etype (Pref, Etype (Task_Proc));
- end if;
-
- -- Similarly, the address of a protected operation is the address
- -- of the corresponding protected body, regardless of the protected
- -- object from which it is selected.
-
- elsif Nkind (Pref) = N_Selected_Component
- and then Is_Subprogram (Entity (Selector_Name (Pref)))
- and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
- then
- Rewrite (Pref,
- New_Occurrence_Of (
- External_Subprogram (Entity (Selector_Name (Pref))), Loc));
-
- elsif Nkind (Pref) = N_Explicit_Dereference
- and then Ekind (Etype (Pref)) = E_Subprogram_Type
- and then Convention (Etype (Pref)) = Convention_Protected
- then
- -- The prefix is be a dereference of an access_to_protected_
- -- subprogram. The desired address is the second component of
- -- the record that represents the access.
-
- declare
- Addr : constant Entity_Id := Etype (N);
- Ptr : constant Node_Id := Prefix (Pref);
- T : constant Entity_Id :=
- Equivalent_Type (Base_Type (Etype (Ptr)));
-
- begin
- Rewrite (N,
- Unchecked_Convert_To (Addr,
- Make_Selected_Component (Loc,
- Prefix => Unchecked_Convert_To (T, Ptr),
- Selector_Name => New_Occurrence_Of (
- Next_Entity (First_Entity (T)), Loc))));
-
- Analyze_And_Resolve (N, Addr);
- end;
- end if;
-
- -- Deal with packed array reference, other cases are handled by gigi
-
- if Involves_Packed_Array_Reference (Pref) then
- Expand_Packed_Address_Reference (N);
- end if;
- end Address;
-
- ---------------
- -- AST_Entry --
- ---------------
-
- when Attribute_AST_Entry => AST_Entry : declare
- Ttyp : Entity_Id;
- T_Id : Node_Id;
- Eent : Entity_Id;
-
- Entry_Ref : Node_Id;
- -- The reference to the entry or entry family
-
- Index : Node_Id;
- -- The index expression for an entry family reference, or
- -- the Empty if Entry_Ref references a simple entry.
-
- begin
- if Nkind (Pref) = N_Indexed_Component then
- Entry_Ref := Prefix (Pref);
- Index := First (Expressions (Pref));
- else
- Entry_Ref := Pref;
- Index := Empty;
- end if;
-
- -- Get expression for Task_Id and the entry entity
-
- if Nkind (Entry_Ref) = N_Selected_Component then
- T_Id :=
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Identity,
- Prefix => Prefix (Entry_Ref));
-
- Ttyp := Etype (Prefix (Entry_Ref));
- Eent := Entity (Selector_Name (Entry_Ref));
-
- else
- T_Id :=
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
-
- Eent := Entity (Entry_Ref);
-
- -- We have to find the enclosing task to get the task type
- -- There must be one, since we already validated this earlier
-
- Ttyp := Current_Scope;
- while not Is_Task_Type (Ttyp) loop
- Ttyp := Scope (Ttyp);
- end loop;
- end if;
-
- -- Now rewrite the attribute with a call to Create_AST_Handler
-
- Rewrite (N,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
- Parameter_Associations => New_List (
- T_Id,
- Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
-
- Analyze_And_Resolve (N, RTE (RE_AST_Handler));
- end AST_Entry;
-
- ------------------
- -- Bit_Position --
- ------------------
-
- -- We compute this if a component clause was present, otherwise
- -- we leave the computation up to Gigi, since we don't know what
- -- layout will be chosen.
-
- -- Note that the attribute can apply to a naked record component
- -- in generated code (i.e. the prefix is an identifier that
- -- references the component or discriminant entity).
-
- when Attribute_Bit_Position => Bit_Position :
- declare
- CE : Entity_Id;
-
- begin
- if Nkind (Pref) = N_Identifier then
- CE := Entity (Pref);
- else
- CE := Entity (Selector_Name (Pref));
- end if;
-
- if Known_Static_Component_Bit_Offset (CE) then
- Rewrite (N,
- Make_Integer_Literal (Loc,
- Intval => Component_Bit_Offset (CE)));
- Analyze_And_Resolve (N, Typ);
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
- end Bit_Position;
-
- ------------------
- -- Body_Version --
- ------------------
-
- -- A reference to P'Body_Version or P'Version is expanded to
-
- -- Vnn : Unsigned;
- -- pragma Import (C, Vnn, "uuuuT";
- -- ...
- -- Get_Version_String (Vnn)
-
- -- where uuuu is the unit name (dots replaced by double underscore)
- -- and T is B for the cases of Body_Version, or Version applied to a
- -- subprogram acting as its own spec, and S for Version applied to a
- -- subprogram spec or package. This sequence of code references the
- -- the unsigned constant created in the main program by the binder.
-
- -- A special exception occurs for Standard, where the string
- -- returned is a copy of the library string in gnatvsn.ads.
-
- when Attribute_Body_Version | Attribute_Version => Version : declare
- E : constant Entity_Id :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
- Pent : Entity_Id := Entity (Pref);
- S : String_Id;
-
- begin
- -- If not library unit, get to containing library unit
-
- while Pent /= Standard_Standard
- and then Scope (Pent) /= Standard_Standard
- loop
- Pent := Scope (Pent);
- end loop;
-
- -- Special case Standard
-
- if Pent = Standard_Standard
- or else Pent = Standard_ASCII
- then
- Name_Buffer (1 .. Library_Version'Length) := Library_Version;
- Name_Len := Library_Version'Length;
- Rewrite (N,
- Make_String_Literal (Loc,
- Strval => String_From_Name_Buffer));
-
- -- All other cases
-
- else
- -- Build required string constant
-
- Get_Name_String (Get_Unit_Name (Pent));
-
- Start_String;
- for J in 1 .. Name_Len - 2 loop
- if Name_Buffer (J) = '.' then
- Store_String_Chars ("__");
- else
- Store_String_Char (Get_Char_Code (Name_Buffer (J)));
- end if;
- end loop;
-
- -- Case of subprogram acting as its own spec, always use body
-
- if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
- and then Nkind (Parent (Declaration_Node (Pent))) =
- N_Subprogram_Body
- and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
- then
- Store_String_Chars ("B");
-
- -- Case of no body present, always use spec
-
- elsif not Unit_Requires_Body (Pent) then
- Store_String_Chars ("S");
-
- -- Otherwise use B for Body_Version, S for spec
-
- elsif Id = Attribute_Body_Version then
- Store_String_Chars ("B");
- else
- Store_String_Chars ("S");
- end if;
-
- S := End_String;
- Lib.Version_Referenced (S);
-
- -- Insert the object declaration
-
- Insert_Actions (N, New_List (
- Make_Object_Declaration (Loc,
- Defining_Identifier => E,
- Object_Definition =>
- New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
-
- -- Set entity as imported with correct external name
-
- Set_Is_Imported (E);
- Set_Interface_Name (E, Make_String_Literal (Loc, S));
-
- -- And now rewrite original reference
-
- Rewrite (N,
- Make_Function_Call (Loc,
- Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
- Parameter_Associations => New_List (
- New_Occurrence_Of (E, Loc))));
- end if;
-
- Analyze_And_Resolve (N, RTE (RE_Version_String));
- end Version;
-
- -------------
- -- Ceiling --
- -------------
-
- -- Transforms 'Ceiling into a call to the floating-point attribute
- -- function Ceiling in Fat_xxx (where xxx is the root type)
-
- when Attribute_Ceiling =>
- Expand_Fpt_Attribute_R (N);
-
- --------------
- -- Callable --
- --------------
-
- -- Transforms 'Callable attribute into a call to the Callable function.
-
- when Attribute_Callable => Callable :
- begin
- Rewrite (N,
- Build_Call_With_Task (Pref, RTE (RE_Callable)));
- Analyze_And_Resolve (N, Standard_Boolean);
- end Callable;
-
- ------------
- -- Caller --
- ------------
-
- -- Transforms 'Caller attribute into a call to either the
- -- Task_Entry_Caller or the Protected_Entry_Caller function.
-
- when Attribute_Caller => Caller : declare
- Id_Kind : Entity_Id := RTE (RO_AT_Task_ID);
- Ent : Entity_Id := Entity (Pref);
- Conctype : Entity_Id := Scope (Ent);
- Nest_Depth : Integer := 0;
- Name : Node_Id;
- S : Entity_Id;
-
- begin
- -- Protected case
-
- if Is_Protected_Type (Conctype) then
- if Abort_Allowed
- or else Restrictions (No_Entry_Queue) = False
- or else Number_Entries (Conctype) > 1
- then
- Name :=
- New_Reference_To
- (RTE (RE_Protected_Entry_Caller), Loc);
- else
- Name :=
- New_Reference_To
- (RTE (RE_Protected_Single_Entry_Caller), Loc);
- end if;
-
- Rewrite (N,
- Unchecked_Convert_To (Id_Kind,
- Make_Function_Call (Loc,
- Name => Name,
- Parameter_Associations => New_List
- (New_Reference_To (
- Object_Ref
- (Corresponding_Body (Parent (Conctype))), Loc)))));
-
- -- Task case
-
- else
- -- Determine the nesting depth of the E'Caller attribute, that
- -- is, how many accept statements are nested within the accept
- -- statement for E at the point of E'Caller. The runtime uses
- -- this depth to find the specified entry call.
-
- for J in reverse 0 .. Scope_Stack.Last loop
- S := Scope_Stack.Table (J).Entity;
-
- -- We should not reach the scope of the entry, as it should
- -- already have been checked in Sem_Attr that this attribute
- -- reference is within a matching accept statement.
-
- pragma Assert (S /= Conctype);
-
- if S = Ent then
- exit;
-
- elsif Is_Entry (S) then
- Nest_Depth := Nest_Depth + 1;
- end if;
- end loop;
-
- Rewrite (N,
- Unchecked_Convert_To (Id_Kind,
- Make_Function_Call (Loc,
- Name => New_Reference_To (
- RTE (RE_Task_Entry_Caller), Loc),
- Parameter_Associations => New_List (
- Make_Integer_Literal (Loc,
- Intval => Int (Nest_Depth))))));
- end if;
-
- Analyze_And_Resolve (N, Id_Kind);
- end Caller;
-
- -------------
- -- Compose --
- -------------
-
- -- Transforms 'Compose into a call to the floating-point attribute
- -- function Compose in Fat_xxx (where xxx is the root type)
-
- -- Note: we strictly should have special code here to deal with the
- -- case of absurdly negative arguments (less than Integer'First)
- -- which will return a (signed) zero value, but it hardly seems
- -- worth the effort. Absurdly large positive arguments will raise
- -- constraint error which is fine.
-
- when Attribute_Compose =>
- Expand_Fpt_Attribute_RI (N);
-
- -----------------
- -- Constrained --
- -----------------
-
- when Attribute_Constrained => Constrained : declare
- Formal_Ent : constant Entity_Id := Param_Entity (Pref);
-
- begin
- -- Reference to a parameter where the value is passed as an extra
- -- actual, corresponding to the extra formal referenced by the
- -- Extra_Constrained field of the corresponding formal.
-
- if Present (Formal_Ent)
- and then Present (Extra_Constrained (Formal_Ent))
- then
- Rewrite (N,
- New_Occurrence_Of
- (Extra_Constrained (Formal_Ent), Sloc (N)));
-
- -- For variables with a Extra_Constrained field, we use the
- -- corresponding entity.
-
- elsif Nkind (Pref) = N_Identifier
- and then Ekind (Entity (Pref)) = E_Variable
- and then Present (Extra_Constrained (Entity (Pref)))
- then
- Rewrite (N,
- New_Occurrence_Of
- (Extra_Constrained (Entity (Pref)), Sloc (N)));
-
- -- For all other entity names, we can tell at compile time
-
- elsif Is_Entity_Name (Pref) then
- declare
- Ent : constant Entity_Id := Entity (Pref);
- Res : Boolean;
-
- begin
- -- (RM J.4) obsolescent cases
-
- if Is_Type (Ent) then
-
- -- Private type
-
- if Is_Private_Type (Ent) then
- Res := not Has_Discriminants (Ent)
- or else Is_Constrained (Ent);
-
- -- It not a private type, must be a generic actual type
- -- that corresponded to a private type. We know that this
- -- correspondence holds, since otherwise the reference
- -- within the generic template would have been illegal.
-
- else
- declare
- UT : Entity_Id := Underlying_Type (Ent);
-
- begin
- if Is_Composite_Type (UT) then
- Res := Is_Constrained (Ent);
- else
- Res := True;
- end if;
- end;
- end if;
-
- -- If the prefix is not a variable or is aliased, then
- -- definitely true; if it's a formal parameter without
- -- an associated extra formal, then treat it as constrained.
-
- elsif not Is_Variable (Pref)
- or else Present (Formal_Ent)
- or else Is_Aliased_View (Pref)
- then
- Res := True;
-
- -- Variable case, just look at type to see if it is
- -- constrained. Note that the one case where this is
- -- not accurate (the procedure formal case), has been
- -- handled above.
-
- else
- Res := Is_Constrained (Etype (Ent));
- end if;
-
- if Res then
- Rewrite (N,
- New_Reference_To (Standard_True, Loc));
- else
- Rewrite (N,
- New_Reference_To (Standard_False, Loc));
- end if;
- end;
-
- -- Prefix is not an entity name. These are also cases where
- -- we can always tell at compile time by looking at the form
- -- and type of the prefix.
-
- else
- if not Is_Variable (Pref)
- or else Nkind (Pref) = N_Explicit_Dereference
- or else Is_Constrained (Etype (Pref))
- then
- Rewrite (N,
- New_Reference_To (Standard_True, Loc));
- else
- Rewrite (N,
- New_Reference_To (Standard_False, Loc));
- end if;
- end if;
-
- Analyze_And_Resolve (N, Standard_Boolean);
- end Constrained;
-
- ---------------
- -- Copy_Sign --
- ---------------
-
- -- Transforms 'Copy_Sign into a call to the floating-point attribute
- -- function Copy_Sign in Fat_xxx (where xxx is the root type)
-
- when Attribute_Copy_Sign =>
- Expand_Fpt_Attribute_RR (N);
-
- -----------
- -- Count --
- -----------
-
- -- Transforms 'Count attribute into a call to the Count function
-
- when Attribute_Count => Count :
- declare
- Entnam : Node_Id;
- Index : Node_Id;
- Name : Node_Id;
- Call : Node_Id;
- Conctyp : Entity_Id;
-
- begin
- -- If the prefix is a member of an entry family, retrieve both
- -- entry name and index. For a simple entry there is no index.
-
- if Nkind (Pref) = N_Indexed_Component then
- Entnam := Prefix (Pref);
- Index := First (Expressions (Pref));
- else
- Entnam := Pref;
- Index := Empty;
- end if;
-
- -- Find the concurrent type in which this attribute is referenced
- -- (there had better be one).
-
- Conctyp := Current_Scope;
- while not Is_Concurrent_Type (Conctyp) loop
- Conctyp := Scope (Conctyp);
- end loop;
-
- -- Protected case
-
- if Is_Protected_Type (Conctyp) then
-
- if Abort_Allowed
- or else Restrictions (No_Entry_Queue) = False
- or else Number_Entries (Conctyp) > 1
- then
- Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
-
- Call :=
- Make_Function_Call (Loc,
- Name => Name,
- Parameter_Associations => New_List (
- New_Reference_To (
- Object_Ref (
- Corresponding_Body (Parent (Conctyp))), Loc),
- Entry_Index_Expression (
- Loc, Entity (Entnam), Index, Scope (Entity (Entnam)))));
- else
- Name := New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
-
- Call := Make_Function_Call (Loc,
- Name => Name,
- Parameter_Associations => New_List (
- New_Reference_To (
- Object_Ref (
- Corresponding_Body (Parent (Conctyp))), Loc)));
- end if;
-
- -- Task case
-
- else
- Call :=
- Make_Function_Call (Loc,
- Name => New_Reference_To (RTE (RE_Task_Count), Loc),
- Parameter_Associations => New_List (
- Entry_Index_Expression
- (Loc, Entity (Entnam), Index, Scope (Entity (Entnam)))));
- end if;
-
- -- The call returns type Natural but the context is universal integer
- -- so any integer type is allowed. The attribute was already resolved
- -- so its Etype is the required result type. If the base type of the
- -- context type is other than Standard.Integer we put in a conversion
- -- to the required type. This can be a normal typed conversion since
- -- both input and output types of the conversion are integer types
-
- if Base_Type (Typ) /= Base_Type (Standard_Integer) then
- Rewrite (N, Convert_To (Typ, Call));
- else
- Rewrite (N, Call);
- end if;
-
- Analyze_And_Resolve (N, Typ);
- end Count;
-
- ---------------
- -- Elab_Body --
- ---------------
-
- -- This processing is shared by Elab_Spec
-
- -- What we do is to insert the following declarations
-
- -- procedure tnn;
- -- pragma Import (C, enn, "name___elabb/s");
-
- -- and then the Elab_Body/Spec attribute is replaced by a reference
- -- to this defining identifier.
-
- when Attribute_Elab_Body |
- Attribute_Elab_Spec =>
-
- Elab_Body : declare
- Ent : constant Entity_Id :=
- Make_Defining_Identifier (Loc,
- New_Internal_Name ('E'));
- Str : String_Id;
- Lang : Node_Id;
-
- procedure Make_Elab_String (Nod : Node_Id);
- -- Given Nod, an identifier, or a selected component, put the
- -- image into the current string literal, with double underline
- -- between components.
-
- procedure Make_Elab_String (Nod : Node_Id) is
- begin
- if Nkind (Nod) = N_Selected_Component then
- Make_Elab_String (Prefix (Nod));
- if Java_VM then
- Store_String_Char ('$');
- else
- Store_String_Char ('_');
- Store_String_Char ('_');
- end if;
-
- Get_Name_String (Chars (Selector_Name (Nod)));
-
- else
- pragma Assert (Nkind (Nod) = N_Identifier);
- Get_Name_String (Chars (Nod));
- end if;
-
- Store_String_Chars (Name_Buffer (1 .. Name_Len));
- end Make_Elab_String;
-
- -- Start of processing for Elab_Body/Elab_Spec
-
- begin
- -- First we need to prepare the string literal for the name of
- -- the elaboration routine to be referenced.
-
- Start_String;
- Make_Elab_String (Pref);
-
- if Java_VM then
- Store_String_Chars ("._elab");
- Lang := Make_Identifier (Loc, Name_Ada);
- else
- Store_String_Chars ("___elab");
- Lang := Make_Identifier (Loc, Name_C);
- end if;
-
- if Id = Attribute_Elab_Body then
- Store_String_Char ('b');
- else
- Store_String_Char ('s');
- end if;
-
- Str := End_String;
-
- Insert_Actions (N, New_List (
- Make_Subprogram_Declaration (Loc,
- Specification =>
- Make_Procedure_Specification (Loc,
- Defining_Unit_Name => Ent)),
-
- Make_Pragma (Loc,
- Chars => Name_Import,
- Pragma_Argument_Associations => New_List (
- Make_Pragma_Argument_Association (Loc,
- Expression => Lang),
-
- Make_Pragma_Argument_Association (Loc,
- Expression =>
- Make_Identifier (Loc, Chars (Ent))),
-
- Make_Pragma_Argument_Association (Loc,
- Expression =>
- Make_String_Literal (Loc, Str))))));
-
- Set_Entity (N, Ent);
- Rewrite (N, New_Occurrence_Of (Ent, Loc));
- end Elab_Body;
-
- ----------------
- -- Elaborated --
- ----------------
-
- -- Elaborated is always True for preelaborated units, predefined
- -- units, pure units and units which have Elaborate_Body pragmas.
- -- These units have no elaboration entity.
-
- -- Note: The Elaborated attribute is never passed through to Gigi
-
- when Attribute_Elaborated => Elaborated : declare
- Ent : constant Entity_Id := Entity (Pref);
-
- begin
- if Present (Elaboration_Entity (Ent)) then
- Rewrite (N,
- New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
- else
- Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
- end if;
- end Elaborated;
-
- --------------
- -- Enum_Rep --
- --------------
-
- when Attribute_Enum_Rep => Enum_Rep :
- begin
- -- X'Enum_Rep (Y) expands to
-
- -- target-type (Y)
-
- -- This is simply a direct conversion from the enumeration type
- -- to the target integer type, which is treated by Gigi as a normal
- -- integer conversion, treating the enumeration type as an integer,
- -- which is exactly what we want! We set Conversion_OK to make sure
- -- that the analyzer does not complain about what otherwise might
- -- be an illegal conversion.
-
- if Is_Non_Empty_List (Exprs) then
- Rewrite (N,
- OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
-
- -- X'Enum_Rep where X is an enumeration literal is replaced by
- -- the literal value.
-
- elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
- Rewrite (N,
- Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
-
- -- X'Enum_Rep where X is an object does a direct unchecked conversion
- -- of the object value, as described for the type case above.
-
- else
- Rewrite (N,
- OK_Convert_To (Typ, Relocate_Node (Pref)));
- end if;
-
- Set_Etype (N, Typ);
- Analyze_And_Resolve (N, Typ);
-
- end Enum_Rep;
-
- --------------
- -- Exponent --
- --------------
-
- -- Transforms 'Exponent into a call to the floating-point attribute
- -- function Exponent in Fat_xxx (where xxx is the root type)
-
- when Attribute_Exponent =>
- Expand_Fpt_Attribute_R (N);
-
- ------------------
- -- External_Tag --
- ------------------
-
- -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
-
- when Attribute_External_Tag => External_Tag :
- begin
- Rewrite (N,
- Make_Function_Call (Loc,
- Name => New_Reference_To (RTE (RE_External_Tag), Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Tag,
- Prefix => Prefix (N)))));
-
- Analyze_And_Resolve (N, Standard_String);
- end External_Tag;
-
- -----------
- -- First --
- -----------
-
- when Attribute_First => declare
- Ptyp : constant Entity_Id := Etype (Pref);
-
- begin
- -- If the prefix type is a constrained packed array type which
- -- already has a Packed_Array_Type representation defined, then
- -- replace this attribute with a direct reference to 'First of the
- -- appropriate index subtype (since otherwise Gigi will try to give
- -- us the value of 'First for this implementation type).
-
- if Is_Constrained_Packed_Array (Ptyp) then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_First,
- Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
- Analyze_And_Resolve (N, Typ);
-
- elsif Is_Access_Type (Ptyp) then
- Apply_Access_Check (N);
- end if;
- end;
-
- ---------------
- -- First_Bit --
- ---------------
-
- -- We compute this if a component clause was present, otherwise
- -- we leave the computation up to Gigi, since we don't know what
- -- layout will be chosen.
-
- when Attribute_First_Bit => First_Bit :
- declare
- CE : constant Entity_Id := Entity (Selector_Name (Pref));
-
- begin
- if Known_Static_Component_Bit_Offset (CE) then
- Rewrite (N,
- Make_Integer_Literal (Loc,
- Component_Bit_Offset (CE) mod System_Storage_Unit));
-
- Analyze_And_Resolve (N, Typ);
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
- end First_Bit;
-
- -----------------
- -- Fixed_Value --
- -----------------
-
- -- We transform:
-
- -- fixtype'Fixed_Value (integer-value)
-
- -- into
-
- -- fixtype(integer-value)
-
- -- we do all the required analysis of the conversion here, because
- -- we do not want this to go through the fixed-point conversion
- -- circuits. Note that gigi always treats fixed-point as equivalent
- -- to the corresponding integer type anyway.
-
- when Attribute_Fixed_Value => Fixed_Value :
- begin
- Rewrite (N,
- Make_Type_Conversion (Loc,
- Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
- Expression => Relocate_Node (First (Exprs))));
- Set_Etype (N, Entity (Pref));
- Set_Analyzed (N);
- Apply_Type_Conversion_Checks (N);
- end Fixed_Value;
-
- -----------
- -- Floor --
- -----------
-
- -- Transforms 'Floor into a call to the floating-point attribute
- -- function Floor in Fat_xxx (where xxx is the root type)
-
- when Attribute_Floor =>
- Expand_Fpt_Attribute_R (N);
-
- ----------
- -- Fore --
- ----------
-
- -- For the fixed-point type Typ:
-
- -- Typ'Fore
-
- -- expands into
-
- -- Result_Type (System.Fore (Long_Long_Float (Type'First)),
- -- Long_Long_Float (Type'Last))
-
- -- Note that we know that the type is a non-static subtype, or Fore
- -- would have itself been computed dynamically in Eval_Attribute.
-
- when Attribute_Fore => Fore :
- declare
- Ptyp : constant Entity_Id := Etype (Pref);
-
- begin
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name => New_Reference_To (RTE (RE_Fore), Loc),
-
- Parameter_Associations => New_List (
- Convert_To (Standard_Long_Long_Float,
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Ptyp, Loc),
- Attribute_Name => Name_First)),
-
- Convert_To (Standard_Long_Long_Float,
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Ptyp, Loc),
- Attribute_Name => Name_Last))))));
-
- Analyze_And_Resolve (N, Typ);
- end Fore;
-
- --------------
- -- Fraction --
- --------------
-
- -- Transforms 'Fraction into a call to the floating-point attribute
- -- function Fraction in Fat_xxx (where xxx is the root type)
-
- when Attribute_Fraction =>
- Expand_Fpt_Attribute_R (N);
-
- --------------
- -- Identity --
- --------------
-
- -- For an exception returns a reference to the exception data:
- -- Exception_Id!(Prefix'Reference)
-
- -- For a task it returns a reference to the _task_id component of
- -- corresponding record:
-
- -- taskV!(Prefix)._Task_Id, converted to the type Task_ID defined
-
- -- in Ada.Task_Identification.
-
- when Attribute_Identity => Identity : declare
- Id_Kind : Entity_Id;
-
- begin
- if Etype (Pref) = Standard_Exception_Type then
- Id_Kind := RTE (RE_Exception_Id);
-
- if Present (Renamed_Object (Entity (Pref))) then
- Set_Entity (Pref, Renamed_Object (Entity (Pref)));
- end if;
-
- Rewrite (N,
- Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
- else
- Id_Kind := RTE (RO_AT_Task_ID);
-
- Rewrite (N,
- Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
- end if;
-
- Analyze_And_Resolve (N, Id_Kind);
- end Identity;
-
- -----------
- -- Image --
- -----------
-
- -- Image attribute is handled in separate unit Exp_Imgv
-
- when Attribute_Image =>
- Exp_Imgv.Expand_Image_Attribute (N);
-
- ---------
- -- Img --
- ---------
-
- -- X'Img is expanded to typ'Image (X), where typ is the type of X
-
- when Attribute_Img => Img :
- begin
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Etype (Pref), Loc),
- Attribute_Name => Name_Image,
- Expressions => New_List (Relocate_Node (Pref))));
-
- Analyze_And_Resolve (N, Standard_String);
- end Img;
-
- -----------
- -- Input --
- -----------
-
- when Attribute_Input => Input : declare
- P_Type : constant Entity_Id := Entity (Pref);
- B_Type : constant Entity_Id := Base_Type (P_Type);
- U_Type : constant Entity_Id := Underlying_Type (P_Type);
- Strm : constant Node_Id := First (Exprs);
- Fname : Entity_Id;
- Decl : Node_Id;
- Call : Node_Id;
- Prag : Node_Id;
- Arg2 : Node_Id;
- Rfunc : Node_Id;
-
- Cntrl : Node_Id := Empty;
- -- Value for controlling argument in call. Always Empty except in
- -- the dispatching (class-wide type) case, where it is a reference
- -- to the dummy object initialized to the right internal tag.
-
- begin
- -- If no underlying type, we have an error that will be diagnosed
- -- elsewhere, so here we just completely ignore the expansion.
-
- if No (U_Type) then
- return;
- end if;
-
- -- If there is a TSS for Input, just call it
-
- Fname := Find_Inherited_TSS (P_Type, Name_uInput);
-
- if Present (Fname) then
- null;
-
- else
- -- If there is a Stream_Convert pragma, use it, we rewrite
-
- -- sourcetyp'Input (stream)
-
- -- as
-
- -- sourcetyp (streamread (strmtyp'Input (stream)));
-
- -- where stmrearead is the given Read function that converts
- -- an argument of type strmtyp to type sourcetyp or a type
- -- from which it is derived. The extra conversion is required
- -- for the derived case.
-
- Prag :=
- Get_Rep_Pragma
- (Implementation_Base_Type (P_Type), Name_Stream_Convert);
-
- if Present (Prag) then
- Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
- Rfunc := Entity (Expression (Arg2));
-
- Rewrite (N,
- Convert_To (B_Type,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Rfunc, Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of
- (Etype (First_Formal (Rfunc)), Loc),
- Attribute_Name => Name_Input,
- Expressions => Exprs)))));
-
- Analyze_And_Resolve (N, B_Type);
- return;
-
- -- Elementary types
-
- elsif Is_Elementary_Type (U_Type) then
-
- -- A special case arises if we have a defined _Read routine,
- -- since in this case we are required to call this routine.
-
- if Present (TSS (B_Type, Name_uRead)) then
- Build_Record_Or_Elementary_Input_Function
- (Loc, U_Type, Decl, Fname);
- Insert_Action (N, Decl);
-
- -- For normal cases, we call the I_xxx routine directly
-
- else
- Rewrite (N, Build_Elementary_Input_Call (N));
- Analyze_And_Resolve (N, P_Type);
- return;
- end if;
-
- -- Array type case
-
- elsif Is_Array_Type (U_Type) then
- Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
- Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
-
- -- Dispatching case with class-wide type
-
- elsif Is_Class_Wide_Type (P_Type) then
-
- declare
- Rtyp : constant Entity_Id := Root_Type (P_Type);
- Dnn : Entity_Id;
- Decl : Node_Id;
-
- begin
- -- Read the internal tag (RM 13.13.2(34)) and use it to
- -- initialize a dummy tag object:
-
- -- Dnn : Ada.Tags.Tag
- -- := Internal_Tag (String'Input (Strm));
-
- -- This dummy object is used only to provide a controlling
- -- argument for the eventual _Input call.
-
- Dnn :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('D'));
-
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Dnn,
- Object_Definition =>
- New_Occurrence_Of (RTE (RE_Tag), Loc),
- Expression =>
- Make_Function_Call (Loc,
- Name =>
- New_Occurrence_Of (RTE (RE_Internal_Tag), Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of (Standard_String, Loc),
- Attribute_Name => Name_Input,
- Expressions => New_List (
- Relocate_Node
- (Duplicate_Subexpr (Strm)))))));
-
- Insert_Action (N, Decl);
-
- -- Now we need to get the entity for the call, and construct
- -- a function call node, where we preset a reference to Dnn
- -- as the controlling argument (doing an unchecked
- -- conversion to the tagged type to make it look like
- -- a real tagged object).
-
- Fname := Find_Prim_Op (Rtyp, Name_uInput);
- Cntrl := Unchecked_Convert_To (Rtyp,
- New_Occurrence_Of (Dnn, Loc));
- Set_Etype (Cntrl, Rtyp);
- Set_Parent (Cntrl, N);
- end;
-
- -- For tagged types, use the primitive Input function
-
- elsif Is_Tagged_Type (U_Type) then
- Fname := Find_Prim_Op (U_Type, Name_uInput);
-
- -- All other record type cases, including protected records.
- -- The latter only arise for expander generated code for
- -- handling shared passive partition access.
-
- else
- pragma Assert
- (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-
- Build_Record_Or_Elementary_Input_Function
- (Loc, Base_Type (U_Type), Decl, Fname);
- Insert_Action (N, Decl);
- end if;
- end if;
-
- -- If we fall through, Fname is the function to be called. The
- -- result is obtained by calling the appropriate function, then
- -- converting the result. The conversion does a subtype check.
-
- Call :=
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Fname, Loc),
- Parameter_Associations => New_List (
- Relocate_Node (Strm)));
-
- Set_Controlling_Argument (Call, Cntrl);
- Rewrite (N, Unchecked_Convert_To (P_Type, Call));
- Analyze_And_Resolve (N, P_Type);
- end Input;
-
- -------------------
- -- Integer_Value --
- -------------------
-
- -- We transform
-
- -- inttype'Fixed_Value (fixed-value)
-
- -- into
-
- -- inttype(integer-value))
-
- -- we do all the required analysis of the conversion here, because
- -- we do not want this to go through the fixed-point conversion
- -- circuits. Note that gigi always treats fixed-point as equivalent
- -- to the corresponding integer type anyway.
-
- when Attribute_Integer_Value => Integer_Value :
- begin
- Rewrite (N,
- Make_Type_Conversion (Loc,
- Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
- Expression => Relocate_Node (First (Exprs))));
- Set_Etype (N, Entity (Pref));
- Set_Analyzed (N);
- Apply_Type_Conversion_Checks (N);
- end Integer_Value;
-
- ----------
- -- Last --
- ----------
-
- when Attribute_Last => declare
- Ptyp : constant Entity_Id := Etype (Pref);
-
- begin
- -- If the prefix type is a constrained packed array type which
- -- already has a Packed_Array_Type representation defined, then
- -- replace this attribute with a direct reference to 'Last of the
- -- appropriate index subtype (since otherwise Gigi will try to give
- -- us the value of 'Last for this implementation type).
-
- if Is_Constrained_Packed_Array (Ptyp) then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Last,
- Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
- Analyze_And_Resolve (N, Typ);
-
- elsif Is_Access_Type (Ptyp) then
- Apply_Access_Check (N);
- end if;
- end;
-
- --------------
- -- Last_Bit --
- --------------
-
- -- We compute this if a component clause was present, otherwise
- -- we leave the computation up to Gigi, since we don't know what
- -- layout will be chosen.
-
- when Attribute_Last_Bit => Last_Bit :
- declare
- CE : constant Entity_Id := Entity (Selector_Name (Pref));
-
- begin
- if Known_Static_Component_Bit_Offset (CE)
- and then Known_Static_Esize (CE)
- then
- Rewrite (N,
- Make_Integer_Literal (Loc,
- Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
- + Esize (CE) - 1));
-
- Analyze_And_Resolve (N, Typ);
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
- end Last_Bit;
-
- ------------------
- -- Leading_Part --
- ------------------
-
- -- Transforms 'Leading_Part into a call to the floating-point attribute
- -- function Leading_Part in Fat_xxx (where xxx is the root type)
-
- -- Note: strictly, we should have special case code to deal with
- -- absurdly large positive arguments (greater than Integer'Last),
- -- which result in returning the first argument unchanged, but it
- -- hardly seems worth the effort. We raise constraint error for
- -- absurdly negative arguments which is fine.
-
- when Attribute_Leading_Part =>
- Expand_Fpt_Attribute_RI (N);
-
- ------------
- -- Length --
- ------------
-
- when Attribute_Length => declare
- Ptyp : constant Entity_Id := Etype (Pref);
- Ityp : Entity_Id;
- Xnum : Uint;
-
- begin
- -- Processing for packed array types
-
- if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
- Ityp := Get_Index_Subtype (N);
-
- -- If the index type, Ityp, is an enumeration type with
- -- holes, then we calculate X'Length explicitly using
-
- -- Typ'Max
- -- (0, Ityp'Pos (X'Last (N)) -
- -- Ityp'Pos (X'First (N)) + 1);
-
- -- Since the bounds in the template are the representation
- -- values and gigi would get the wrong value.
-
- if Is_Enumeration_Type (Ityp)
- and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
- then
- if No (Exprs) then
- Xnum := Uint_1;
- else
- Xnum := Expr_Value (First (Expressions (N)));
- end if;
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Typ, Loc),
- Attribute_Name => Name_Max,
- Expressions => New_List
- (Make_Integer_Literal (Loc, 0),
-
- Make_Op_Add (Loc,
- Left_Opnd =>
- Make_Op_Subtract (Loc,
- Left_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ityp, Loc),
- Attribute_Name => Name_Pos,
-
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Duplicate_Subexpr (Pref),
- Attribute_Name => Name_Last,
- Expressions => New_List (
- Make_Integer_Literal (Loc, Xnum))))),
-
- Right_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ityp, Loc),
- Attribute_Name => Name_Pos,
-
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Duplicate_Subexpr (Pref),
- Attribute_Name => Name_First,
- Expressions => New_List (
- Make_Integer_Literal (Loc, Xnum)))))),
-
- Right_Opnd => Make_Integer_Literal (Loc, 1)))));
-
- Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
- return;
-
- -- If the prefix type is a constrained packed array type which
- -- already has a Packed_Array_Type representation defined, then
- -- replace this attribute with a direct reference to 'Range_Length
- -- of the appropriate index subtype (since otherwise Gigi will try
- -- to give us the value of 'Length for this implementation type).
-
- elsif Is_Constrained (Ptyp) then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Range_Length,
- Prefix => New_Reference_To (Ityp, Loc)));
- Analyze_And_Resolve (N, Typ);
- end if;
-
- -- If we have a packed array that is not bit packed, which was
-
- -- Access type case
-
- elsif Is_Access_Type (Ptyp) then
- Apply_Access_Check (N);
-
- -- If the designated type is a packed array type, then we
- -- convert the reference to:
-
- -- typ'Max (0, 1 +
- -- xtyp'Pos (Pref'Last (Expr)) -
- -- xtyp'Pos (Pref'First (Expr)));
-
- -- This is a bit complex, but it is the easiest thing to do
- -- that works in all cases including enum types with holes
- -- xtyp here is the appropriate index type.
-
- declare
- Dtyp : constant Entity_Id := Designated_Type (Ptyp);
- Xtyp : Entity_Id;
-
- begin
- if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
- Xtyp := Get_Index_Subtype (N);
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Typ, Loc),
- Attribute_Name => Name_Max,
- Expressions => New_List (
- Make_Integer_Literal (Loc, 0),
-
- Make_Op_Add (Loc,
- Make_Integer_Literal (Loc, 1),
- Make_Op_Subtract (Loc,
- Left_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Xtyp, Loc),
- Attribute_Name => Name_Pos,
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Duplicate_Subexpr (Pref),
- Attribute_Name => Name_Last,
- Expressions =>
- New_Copy_List (Exprs)))),
-
- Right_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Xtyp, Loc),
- Attribute_Name => Name_Pos,
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Duplicate_Subexpr (Pref),
- Attribute_Name => Name_First,
- Expressions =>
- New_Copy_List (Exprs)))))))));
-
- Analyze_And_Resolve (N, Typ);
- end if;
- end;
-
- -- Otherwise leave it to gigi
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
- end;
-
- -------------
- -- Machine --
- -------------
-
- -- Transforms 'Machine into a call to the floating-point attribute
- -- function Machine in Fat_xxx (where xxx is the root type)
-
- when Attribute_Machine =>
- Expand_Fpt_Attribute_R (N);
-
- ------------------
- -- Machine_Size --
- ------------------
-
- -- Machine_Size is equivalent to Object_Size, so transform it into
- -- Object_Size and that way Gigi never sees Machine_Size.
-
- when Attribute_Machine_Size =>
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => Prefix (N),
- Attribute_Name => Name_Object_Size));
-
- Analyze_And_Resolve (N, Typ);
-
- --------------
- -- Mantissa --
- --------------
-
- -- The only case that can get this far is the dynamic case of the
- -- old Ada 83 Mantissa attribute for the fixed-point case. For this
- -- case, we expand:
-
- -- typ'Mantissa
-
- -- into
-
- -- ityp (System.Mantissa.Mantissa_Value
- -- (Integer'Integer_Value (typ'First),
- -- Integer'Integer_Value (typ'Last)));
-
- when Attribute_Mantissa => Mantissa : declare
- Ptyp : constant Entity_Id := Etype (Pref);
-
- begin
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
-
- Parameter_Associations => New_List (
-
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Standard_Integer, Loc),
- Attribute_Name => Name_Integer_Value,
- Expressions => New_List (
-
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ptyp, Loc),
- Attribute_Name => Name_First))),
-
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Standard_Integer, Loc),
- Attribute_Name => Name_Integer_Value,
- Expressions => New_List (
-
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ptyp, Loc),
- Attribute_Name => Name_Last)))))));
-
- Analyze_And_Resolve (N, Typ);
- end Mantissa;
-
- -----------
- -- Model --
- -----------
-
- -- Transforms 'Model into a call to the floating-point attribute
- -- function Model in Fat_xxx (where xxx is the root type)
-
- when Attribute_Model =>
- Expand_Fpt_Attribute_R (N);
-
- -----------------
- -- Object_Size --
- -----------------
-
- -- The processing for Object_Size shares the processing for Size
-
- ------------
- -- Output --
- ------------
-
- when Attribute_Output => Output : declare
- P_Type : constant Entity_Id := Entity (Pref);
- B_Type : constant Entity_Id := Base_Type (P_Type);
- U_Type : constant Entity_Id := Underlying_Type (P_Type);
- Pname : Entity_Id;
- Decl : Node_Id;
- Prag : Node_Id;
- Arg3 : Node_Id;
- Wfunc : Node_Id;
-
- begin
- -- If no underlying type, we have an error that will be diagnosed
- -- elsewhere, so here we just completely ignore the expansion.
-
- if No (U_Type) then
- return;
- end if;
-
- -- If TSS for Output is present, just call it
-
- Pname := Find_Inherited_TSS (P_Type, Name_uOutput);
-
- if Present (Pname) then
- null;
-
- else
- -- If there is a Stream_Convert pragma, use it, we rewrite
-
- -- sourcetyp'Output (stream, Item)
-
- -- as
-
- -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
-
- -- where strmwrite is the given Write function that converts
- -- an argument of type sourcetyp or a type acctyp, from which
- -- it is derived to type strmtyp. The conversion to acttyp is
- -- required for the derived case.
-
- Prag :=
- Get_Rep_Pragma
- (Implementation_Base_Type (P_Type), Name_Stream_Convert);
-
- if Present (Prag) then
- Arg3 :=
- Next (Next (First (Pragma_Argument_Associations (Prag))));
- Wfunc := Entity (Expression (Arg3));
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
- Attribute_Name => Name_Output,
- Expressions => New_List (
- Relocate_Node (First (Exprs)),
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Wfunc, Loc),
- Parameter_Associations => New_List (
- Convert_To (Etype (First_Formal (Wfunc)),
- Relocate_Node (Next (First (Exprs)))))))));
-
- Analyze (N);
- return;
-
- -- For elementary types, we call the W_xxx routine directly.
- -- Note that the effect of Write and Output is identical for
- -- the case of an elementary type, since there are no
- -- discriminants or bounds.
-
- elsif Is_Elementary_Type (U_Type) then
-
- -- A special case arises if we have a defined _Write routine,
- -- since in this case we are required to call this routine.
-
- if Present (TSS (B_Type, Name_uWrite)) then
- Build_Record_Or_Elementary_Output_Procedure
- (Loc, U_Type, Decl, Pname);
- Insert_Action (N, Decl);
-
- -- For normal cases, we call the W_xxx routine directly
-
- else
- Rewrite (N, Build_Elementary_Write_Call (N));
- Analyze (N);
- return;
- end if;
-
- -- Array type case
-
- elsif Is_Array_Type (U_Type) then
- Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
- Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
-
- -- Class-wide case, first output external tag, then dispatch
- -- to the appropriate primitive Output function (RM 13.13.2(31)).
-
- elsif Is_Class_Wide_Type (P_Type) then
- Tag_Write : declare
- Strm : constant Node_Id := First (Exprs);
- Item : constant Node_Id := Next (Strm);
-
- begin
- -- The code is:
- -- String'Output (Strm, External_Tag (Item'Tag))
-
- Insert_Action (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Standard_String, Loc),
- Attribute_Name => Name_Output,
- Expressions => New_List (
- Relocate_Node (Duplicate_Subexpr (Strm)),
- Make_Function_Call (Loc,
- Name =>
- New_Occurrence_Of (RTE (RE_External_Tag), Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix =>
- Relocate_Node
- (Duplicate_Subexpr (Item, Name_Req => True)),
- Attribute_Name => Name_Tag))))));
- end Tag_Write;
-
- Pname := Find_Prim_Op (U_Type, Name_uOutput);
-
- -- Tagged type case, use the primitive Output function
-
- elsif Is_Tagged_Type (U_Type) then
- Pname := Find_Prim_Op (U_Type, Name_uOutput);
-
- -- All other record type cases, including protected records.
- -- The latter only arise for expander generated code for
- -- handling shared passive partition access.
-
- else
- pragma Assert
- (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-
- Build_Record_Or_Elementary_Output_Procedure
- (Loc, Base_Type (U_Type), Decl, Pname);
- Insert_Action (N, Decl);
- end if;
- end if;
-
- -- If we fall through, Pname is the name of the procedure to call
-
- Rewrite_Stream_Proc_Call (Pname);
- end Output;
-
- ---------
- -- Pos --
- ---------
-
- -- For enumeration types with a standard representation, Pos is
- -- handled by Gigi.
-
- -- For enumeration types, with a non-standard representation we
- -- generate a call to the _Rep_To_Pos function created when the
- -- type was frozen. The call has the form
-
- -- _rep_to_pos (expr, True)
-
- -- The parameter True causes Program_Error to be raised if the
- -- expression has an invalid representation.
-
- -- For integer types, Pos is equivalent to a simple integer
- -- conversion and we rewrite it as such
-
- when Attribute_Pos => Pos :
- declare
- Etyp : Entity_Id := Base_Type (Entity (Pref));
-
- begin
- -- Deal with zero/non-zero boolean values
-
- if Is_Boolean_Type (Etyp) then
- Adjust_Condition (First (Exprs));
- Etyp := Standard_Boolean;
- Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
- end if;
-
- -- Case of enumeration type
-
- if Is_Enumeration_Type (Etyp) then
-
- -- Non-standard enumeration type (generate call)
-
- if Present (Enum_Pos_To_Rep (Etyp)) then
- Append_To (Exprs, New_Occurrence_Of (Standard_True, Loc));
-
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name =>
- New_Reference_To (TSS (Etyp, Name_uRep_To_Pos), Loc),
- Parameter_Associations => Exprs)));
-
- Analyze_And_Resolve (N, Typ);
-
- -- Standard enumeration type (do universal integer check)
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
-
- -- Deal with integer types (replace by conversion)
-
- elsif Is_Integer_Type (Etyp) then
- Rewrite (N, Convert_To (Typ, First (Exprs)));
- Analyze_And_Resolve (N, Typ);
- end if;
-
- end Pos;
-
- --------------
- -- Position --
- --------------
-
- -- We compute this if a component clause was present, otherwise
- -- we leave the computation up to Gigi, since we don't know what
- -- layout will be chosen.
-
- when Attribute_Position => Position :
- declare
- CE : constant Entity_Id := Entity (Selector_Name (Pref));
-
- begin
- if Present (Component_Clause (CE)) then
- Rewrite (N,
- Make_Integer_Literal (Loc,
- Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
- Analyze_And_Resolve (N, Typ);
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
- end Position;
-
- ----------
- -- Pred --
- ----------
-
- -- 1. Deal with enumeration types with holes
- -- 2. For floating-point, generate call to attribute function
- -- 3. For other cases, deal with constraint checking
-
- when Attribute_Pred => Pred :
- declare
- Ptyp : constant Entity_Id := Base_Type (Etype (Pref));
-
- begin
- -- For enumeration types with non-standard representations, we
- -- expand typ'Pred (x) into
-
- -- Pos_To_Rep (Rep_To_Pos (x) - 1)
-
- if Is_Enumeration_Type (Ptyp)
- and then Present (Enum_Pos_To_Rep (Ptyp))
- then
- -- Add Boolean parameter True, to request program errror if
- -- we have a bad representation on our hands.
-
- Append_To (Exprs, New_Occurrence_Of (Standard_True, Loc));
-
- Rewrite (N,
- Make_Indexed_Component (Loc,
- Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc),
- Expressions => New_List (
- Make_Op_Subtract (Loc,
- Left_Opnd =>
- Make_Function_Call (Loc,
- Name =>
- New_Reference_To (TSS (Ptyp, Name_uRep_To_Pos), Loc),
- Parameter_Associations => Exprs),
- Right_Opnd => Make_Integer_Literal (Loc, 1)))));
-
- Analyze_And_Resolve (N, Typ);
-
- -- For floating-point, we transform 'Pred into a call to the Pred
- -- floating-point attribute function in Fat_xxx (xxx is root type)
-
- elsif Is_Floating_Point_Type (Ptyp) then
- Expand_Fpt_Attribute_R (N);
- Analyze_And_Resolve (N, Typ);
-
- -- For modular types, nothing to do (no overflow, since wraps)
-
- elsif Is_Modular_Integer_Type (Ptyp) then
- null;
-
- -- For other types, if range checking is enabled, we must generate
- -- a check if overflow checking is enabled.
-
- elsif not Overflow_Checks_Suppressed (Ptyp) then
- Expand_Pred_Succ (N);
- end if;
-
- end Pred;
-
- ------------------
- -- Range_Length --
- ------------------
-
- when Attribute_Range_Length => Range_Length : declare
- P_Type : constant Entity_Id := Etype (Pref);
-
- begin
- -- The only special processing required is for the case where
- -- Range_Length is applied to an enumeration type with holes.
- -- In this case we transform
-
- -- X'Range_Length
-
- -- to
-
- -- X'Pos (X'Last) - X'Pos (X'First) + 1
-
- -- So that the result reflects the proper Pos values instead
- -- of the underlying representations.
-
- if Is_Enumeration_Type (P_Type)
- and then Has_Non_Standard_Rep (P_Type)
- then
- Rewrite (N,
- Make_Op_Add (Loc,
- Left_Opnd =>
- Make_Op_Subtract (Loc,
- Left_Opnd =>
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Pos,
- Prefix => New_Occurrence_Of (P_Type, Loc),
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Last,
- Prefix => New_Occurrence_Of (P_Type, Loc)))),
-
- Right_Opnd =>
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_Pos,
- Prefix => New_Occurrence_Of (P_Type, Loc),
- Expressions => New_List (
- Make_Attribute_Reference (Loc,
- Attribute_Name => Name_First,
- Prefix => New_Occurrence_Of (P_Type, Loc))))),
-
- Right_Opnd =>
- Make_Integer_Literal (Loc, 1)));
-
- Analyze_And_Resolve (N, Typ);
-
- -- For all other cases, attribute is handled by Gigi, but we need
- -- to deal with the case of the range check on a universal integer.
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- end if;
-
- end Range_Length;
-
- ----------
- -- Read --
- ----------
-
- when Attribute_Read => Read : declare
- P_Type : constant Entity_Id := Entity (Pref);
- B_Type : constant Entity_Id := Base_Type (P_Type);
- U_Type : constant Entity_Id := Underlying_Type (P_Type);
- Pname : Entity_Id;
- Decl : Node_Id;
- Prag : Node_Id;
- Arg2 : Node_Id;
- Rfunc : Node_Id;
- Lhs : Node_Id;
- Rhs : Node_Id;
-
- begin
- -- If no underlying type, we have an error that will be diagnosed
- -- elsewhere, so here we just completely ignore the expansion.
-
- if No (U_Type) then
- return;
- end if;
-
- -- The simple case, if there is a TSS for Read, just call it
-
- Pname := Find_Inherited_TSS (P_Type, Name_uRead);
-
- if Present (Pname) then
- null;
-
- else
- -- If there is a Stream_Convert pragma, use it, we rewrite
-
- -- sourcetyp'Read (stream, Item)
-
- -- as
-
- -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
-
- -- where strmread is the given Read function that converts
- -- an argument of type strmtyp to type sourcetyp or a type
- -- from which it is derived. The conversion to sourcetyp
- -- is required in the latter case.
-
- -- A special case arises if Item is a type conversion in which
- -- case, we have to expand to:
-
- -- Itemx := typex (strmread (strmtyp'Input (Stream)));
-
- -- where Itemx is the expression of the type conversion (i.e.
- -- the actual object), and typex is the type of Itemx.
-
- Prag :=
- Get_Rep_Pragma
- (Implementation_Base_Type (P_Type), Name_Stream_Convert);
-
- if Present (Prag) then
- Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
- Rfunc := Entity (Expression (Arg2));
- Lhs := Relocate_Node (Next (First (Exprs)));
- Rhs :=
- Convert_To (B_Type,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Rfunc, Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of
- (Etype (First_Formal (Rfunc)), Loc),
- Attribute_Name => Name_Input,
- Expressions => New_List (
- Relocate_Node (First (Exprs)))))));
-
- if Nkind (Lhs) = N_Type_Conversion then
- Lhs := Expression (Lhs);
- Rhs := Convert_To (Etype (Lhs), Rhs);
- end if;
-
- Rewrite (N,
- Make_Assignment_Statement (Loc,
- Name => Lhs,
- Expression => Rhs));
- Set_Assignment_OK (Lhs);
- Analyze (N);
- return;
-
- -- For elementary types, we call the I_xxx routine using the first
- -- parameter and then assign the result into the second parameter.
- -- We set Assignment_OK to deal with the conversion case.
-
- elsif Is_Elementary_Type (U_Type) then
- declare
- Lhs : Node_Id;
- Rhs : Node_Id;
-
- begin
- Lhs := Relocate_Node (Next (First (Exprs)));
- Rhs := Build_Elementary_Input_Call (N);
-
- if Nkind (Lhs) = N_Type_Conversion then
- Lhs := Expression (Lhs);
- Rhs := Convert_To (Etype (Lhs), Rhs);
- end if;
-
- Set_Assignment_OK (Lhs);
-
- Rewrite (N,
- Make_Assignment_Statement (Loc,
- Name => Lhs,
- Expression => Rhs));
-
- Analyze (N);
- return;
- end;
-
- -- Array type case
-
- elsif Is_Array_Type (U_Type) then
- Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
- Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
-
- -- Tagged type case, use the primitive Read function. Note that
- -- this will dispatch in the class-wide case which is what we want
-
- elsif Is_Tagged_Type (U_Type) then
- Pname := Find_Prim_Op (U_Type, Name_uRead);
-
- -- All other record type cases, including protected records.
- -- The latter only arise for expander generated code for
- -- handling shared passive partition access.
-
- else
- pragma Assert
- (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-
- if Has_Discriminants (U_Type)
- and then Present
- (Discriminant_Default_Value (First_Discriminant (U_Type)))
- then
- Build_Mutable_Record_Read_Procedure
- (Loc, Base_Type (U_Type), Decl, Pname);
-
- else
- Build_Record_Read_Procedure
- (Loc, Base_Type (U_Type), Decl, Pname);
- end if;
-
- -- Suppress checks, uninitialized or otherwise invalid
- -- data does not cause constraint errors to be raised for
- -- a complete record read.
-
- Insert_Action (N, Decl, All_Checks);
- end if;
- end if;
-
- Rewrite_Stream_Proc_Call (Pname);
- end Read;
-
- ---------------
- -- Remainder --
- ---------------
-
- -- Transforms 'Remainder into a call to the floating-point attribute
- -- function Remainder in Fat_xxx (where xxx is the root type)
-
- when Attribute_Remainder =>
- Expand_Fpt_Attribute_RR (N);
-
- -----------
- -- Round --
- -----------
-
- -- The handling of the Round attribute is quite delicate. The
- -- processing in Sem_Attr introduced a conversion to universal
- -- real, reflecting the semantics of Round, but we do not want
- -- anything to do with universal real at runtime, since this
- -- corresponds to using floating-point arithmetic.
-
- -- What we have now is that the Etype of the Round attribute
- -- correctly indicates the final result type. The operand of
- -- the Round is the conversion to universal real, described
- -- above, and the operand of this conversion is the actual
- -- operand of Round, which may be the special case of a fixed
- -- point multiplication or division (Etype = universal fixed)
-
- -- The exapander will expand first the operand of the conversion,
- -- then the conversion, and finally the round attribute itself,
- -- since we always work inside out. But we cannot simply process
- -- naively in this order. In the semantic world where universal
- -- fixed and real really exist and have infinite precision, there
- -- is no problem, but in the implementation world, where universal
- -- real is a floating-point type, we would get the wrong result.
-
- -- So the approach is as follows. First, when expanding a multiply
- -- or divide whose type is universal fixed, we do nothing at all,
- -- instead deferring the operation till later.
-
- -- The actual processing is done in Expand_N_Type_Conversion which
- -- handles the special case of Round by looking at its parent to
- -- see if it is a Round attribute, and if it is, handling the
- -- conversion (or its fixed multiply/divide child) in an appropriate
- -- manner.
-
- -- This means that by the time we get to expanding the Round attribute
- -- itself, the Round is nothing more than a type conversion (and will
- -- often be a null type conversion), so we just replace it with the
- -- appropriate conversion operation.
-
- when Attribute_Round =>
- Rewrite (N,
- Convert_To (Etype (N), Relocate_Node (First (Exprs))));
- Analyze_And_Resolve (N);
-
- --------------
- -- Rounding --
- --------------
-
- -- Transforms 'Rounding into a call to the floating-point attribute
- -- function Rounding in Fat_xxx (where xxx is the root type)
-
- when Attribute_Rounding =>
- Expand_Fpt_Attribute_R (N);
-
- -------------
- -- Scaling --
- -------------
-
- -- Transforms 'Scaling into a call to the floating-point attribute
- -- function Scaling in Fat_xxx (where xxx is the root type)
-
- when Attribute_Scaling =>
- Expand_Fpt_Attribute_RI (N);
-
- ----------
- -- Size --
- ----------
-
- when Attribute_Size |
- Attribute_Object_Size |
- Attribute_Value_Size |
- Attribute_VADS_Size => Size :
-
- declare
- Ptyp : constant Entity_Id := Etype (Pref);
- New_Node : Node_Id;
- Siz : Uint;
-
- begin
- -- Processing for VADS_Size case. Note that this processing removes
- -- all traces of VADS_Size from the tree, and completes all required
- -- processing for VADS_Size by translating the attribute reference
- -- to an appropriate Size or Object_Size reference.
-
- if Id = Attribute_VADS_Size
- or else (Use_VADS_Size and then Id = Attribute_Size)
- then
- -- If the size is specified, then we simply use the specified
- -- size. This applies to both types and objects. The size of an
- -- object can be specified in the following ways:
-
- -- An explicit size object is given for an object
- -- A component size is specified for an indexed component
- -- A component clause is specified for a selected component
- -- The object is a component of a packed composite object
-
- -- If the size is specified, then VADS_Size of an object
-
- if (Is_Entity_Name (Pref)
- and then Present (Size_Clause (Entity (Pref))))
- or else
- (Nkind (Pref) = N_Component_Clause
- and then (Present (Component_Clause
- (Entity (Selector_Name (Pref))))
- or else Is_Packed (Etype (Prefix (Pref)))))
- or else
- (Nkind (Pref) = N_Indexed_Component
- and then (Component_Size (Etype (Prefix (Pref))) /= 0
- or else Is_Packed (Etype (Prefix (Pref)))))
- then
- Set_Attribute_Name (N, Name_Size);
-
- -- Otherwise if we have an object rather than a type, then the
- -- VADS_Size attribute applies to the type of the object, rather
- -- than the object itself. This is one of the respects in which
- -- VADS_Size differs from Size.
-
- else
- if (not Is_Entity_Name (Pref)
- or else not Is_Type (Entity (Pref)))
- and then (Is_Scalar_Type (Etype (Pref))
- or else Is_Constrained (Etype (Pref)))
- then
- Rewrite (Pref, New_Occurrence_Of (Etype (Pref), Loc));
- end if;
-
- -- For a scalar type for which no size was
- -- explicitly given, VADS_Size means Object_Size. This is the
- -- other respect in which VADS_Size differs from Size.
-
- if Is_Scalar_Type (Etype (Pref))
- and then No (Size_Clause (Etype (Pref)))
- then
- Set_Attribute_Name (N, Name_Object_Size);
-
- -- In all other cases, Size and VADS_Size are the sane
-
- else
- Set_Attribute_Name (N, Name_Size);
- end if;
- end if;
- end if;
-
- -- For class-wide types, transform X'Size into a call to
- -- the primitive operation _Size
-
- if Is_Class_Wide_Type (Ptyp) then
- New_Node :=
- Make_Function_Call (Loc,
- Name => New_Reference_To
- (Find_Prim_Op (Ptyp, Name_uSize), Loc),
- Parameter_Associations => New_List (Pref));
-
- if Typ /= Standard_Long_Long_Integer then
-
- -- The context is a specific integer type with which the
- -- original attribute was compatible. The function has a
- -- specific type as well, so to preserve the compatibility
- -- we must convert explicitly.
-
- New_Node := Convert_To (Typ, New_Node);
- end if;
-
- Rewrite (N, New_Node);
- Analyze_And_Resolve (N, Typ);
- return;
-
- -- For an array component, we can do Size in the front end
- -- if the component_size of the array is set.
-
- elsif Nkind (Pref) = N_Indexed_Component then
- Siz := Component_Size (Etype (Prefix (Pref)));
-
- -- For a record component, we can do Size in the front end
- -- if there is a component clause, or if the record is packed
- -- and the component's size is known at compile time.
-
- elsif Nkind (Pref) = N_Selected_Component then
- declare
- Rec : constant Entity_Id := Etype (Prefix (Pref));
- Comp : constant Entity_Id := Entity (Selector_Name (Pref));
-
- begin
- if Present (Component_Clause (Comp)) then
- Siz := Esize (Comp);
-
- elsif Is_Packed (Rec) then
- Siz := RM_Size (Ptyp);
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
- return;
- end if;
- end;
-
- -- All other cases are handled by Gigi
-
- else
- Apply_Universal_Integer_Attribute_Checks (N);
-
- -- If we have Size applied to a formal parameter, that is a
- -- packed array subtype, then apply size to the actual subtype.
-
- if Is_Entity_Name (Pref)
- and then Is_Formal (Entity (Pref))
- and then Is_Array_Type (Etype (Pref))
- and then Is_Packed (Etype (Pref))
- then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
- Attribute_Name => Name_Size));
- Analyze_And_Resolve (N, Typ);
- end if;
-
- return;
- end if;
-
- -- Common processing for record and array component case
-
- if Siz /= 0 then
- Rewrite (N,
- Make_Integer_Literal (Loc, Siz));
-
- Analyze_And_Resolve (N, Typ);
-
- -- The result is not a static expression
-
- Set_Is_Static_Expression (N, False);
- end if;
- end Size;
-
- ------------------
- -- Storage_Pool --
- ------------------
-
- when Attribute_Storage_Pool =>
- Rewrite (N,
- Make_Type_Conversion (Loc,
- Subtype_Mark => New_Reference_To (Etype (N), Loc),
- Expression => New_Reference_To (Entity (N), Loc)));
- Analyze_And_Resolve (N, Typ);
-
- ------------------
- -- Storage_Size --
- ------------------
-
- when Attribute_Storage_Size => Storage_Size :
- declare
- Ptyp : constant Entity_Id := Etype (Pref);
-
- begin
- -- Access type case, always go to the root type
-
- -- The case of access types results in a value of zero for the case
- -- where no storage size attribute clause has been given. If a
- -- storage size has been given, then the attribute is converted
- -- to a reference to the variable used to hold this value.
-
- if Is_Access_Type (Ptyp) then
- if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Typ, Loc),
- Attribute_Name => Name_Max,
- Expressions => New_List (
- Make_Integer_Literal (Loc, 0),
- Convert_To (Typ,
- New_Reference_To
- (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
-
- elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
- Rewrite (N,
- OK_Convert_To (Typ,
- Make_Function_Call (Loc,
- Name => New_Reference_To (Find_Prim_Op (Etype (
- Associated_Storage_Pool (Root_Type (Ptyp))),
- Attribute_Name (N)), Loc),
-
- Parameter_Associations => New_List (New_Reference_To (
- Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
- else
- Rewrite (N, Make_Integer_Literal (Loc, 0));
- end if;
-
- Analyze_And_Resolve (N, Typ);
-
- -- The case of a task type (an obsolescent feature) is handled the
- -- same way, seems as reasonable as anything, and it is what the
- -- ACVC tests (e.g. CD1009K) seem to expect.
-
- -- If there is no Storage_Size variable, then we return the default
- -- task stack size, otherwise, expand a Storage_Size attribute as
- -- follows:
-
- -- Typ (Adjust_Storage_Size (taskZ))
-
- -- except for the case of a task object which has a Storage_Size
- -- pragma:
-
- -- Typ (Adjust_Storage_Size (taskV!(name)._Size))
-
- else
- if not Present (Storage_Size_Variable (Ptyp)) then
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name =>
- New_Occurrence_Of (RTE (RE_Default_Stack_Size), Loc))));
-
- else
- if not (Is_Entity_Name (Pref) and then
- Is_Task_Type (Entity (Pref))) and then
- Chars (Last_Entity (Corresponding_Record_Type (Ptyp))) =
- Name_uSize
- then
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (
- RTE (RE_Adjust_Storage_Size), Loc),
- Parameter_Associations =>
- New_List (
- Make_Selected_Component (Loc,
- Prefix =>
- Unchecked_Convert_To (
- Corresponding_Record_Type (Ptyp),
- New_Copy_Tree (Pref)),
- Selector_Name =>
- Make_Identifier (Loc, Name_uSize))))));
-
- -- Task not having Storage_Size pragma
-
- else
- Rewrite (N,
- Convert_To (Typ,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (
- RTE (RE_Adjust_Storage_Size), Loc),
- Parameter_Associations =>
- New_List (
- New_Reference_To (
- Storage_Size_Variable (Ptyp), Loc)))));
- end if;
-
- Analyze_And_Resolve (N, Typ);
- end if;
- end if;
- end Storage_Size;
-
- ----------
- -- Succ --
- ----------
-
- -- 1. Deal with enumeration types with holes
- -- 2. For floating-point, generate call to attribute function
- -- 3. For other cases, deal with constraint checking
-
- when Attribute_Succ => Succ :
- declare
- Ptyp : constant Entity_Id := Base_Type (Etype (Pref));
-
- begin
- -- For enumeration types with non-standard representations, we
- -- expand typ'Succ (x) into
-
- -- Pos_To_Rep (Rep_To_Pos (x) + 1)
-
- if Is_Enumeration_Type (Ptyp)
- and then Present (Enum_Pos_To_Rep (Ptyp))
- then
- -- Add Boolean parameter True, to request program errror if
- -- we have a bad representation on our hands.
-
- Append_To (Exprs, New_Occurrence_Of (Standard_True, Loc));
-
- Rewrite (N,
- Make_Indexed_Component (Loc,
- Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc),
- Expressions => New_List (
- Make_Op_Add (Loc,
- Left_Opnd =>
- Make_Function_Call (Loc,
- Name =>
- New_Reference_To (TSS (Ptyp, Name_uRep_To_Pos), Loc),
- Parameter_Associations => Exprs),
- Right_Opnd => Make_Integer_Literal (Loc, 1)))));
-
- Analyze_And_Resolve (N, Typ);
-
- -- For floating-point, we transform 'Succ into a call to the Succ
- -- floating-point attribute function in Fat_xxx (xxx is root type)
-
- elsif Is_Floating_Point_Type (Ptyp) then
- Expand_Fpt_Attribute_R (N);
- Analyze_And_Resolve (N, Typ);
-
- -- For modular types, nothing to do (no overflow, since wraps)
-
- elsif Is_Modular_Integer_Type (Ptyp) then
- null;
-
- -- For other types, if range checking is enabled, we must generate
- -- a check if overflow checking is enabled.
-
- elsif not Overflow_Checks_Suppressed (Ptyp) then
- Expand_Pred_Succ (N);
- end if;
- end Succ;
-
- ---------
- -- Tag --
- ---------
-
- -- Transforms X'Tag into a direct reference to the tag of X
-
- when Attribute_Tag => Tag :
- declare
- Ttyp : Entity_Id;
- Prefix_Is_Type : Boolean;
-
- begin
- if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
- Ttyp := Entity (Pref);
- Prefix_Is_Type := True;
- else
- Ttyp := Etype (Pref);
- Prefix_Is_Type := False;
- end if;
-
- if Is_Class_Wide_Type (Ttyp) then
- Ttyp := Root_Type (Ttyp);
- end if;
-
- Ttyp := Underlying_Type (Ttyp);
-
- if Prefix_Is_Type then
-
- -- For JGNAT we leave the type attribute unexpanded because
- -- there's not a dispatching table to reference.
-
- if not Java_VM then
- Rewrite (N,
- Unchecked_Convert_To (RTE (RE_Tag),
- New_Reference_To (Access_Disp_Table (Ttyp), Loc)));
- Analyze_And_Resolve (N, RTE (RE_Tag));
- end if;
-
- else
- Rewrite (N,
- Make_Selected_Component (Loc,
- Prefix => Relocate_Node (Pref),
- Selector_Name =>
- New_Reference_To (Tag_Component (Ttyp), Loc)));
- Analyze_And_Resolve (N, RTE (RE_Tag));
- end if;
- end Tag;
-
- ----------------
- -- Terminated --
- ----------------
-
- -- Transforms 'Terminated attribute into a call to Terminated function.
-
- when Attribute_Terminated => Terminated :
- begin
- if Restricted_Profile then
- Rewrite (N,
- Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
-
- else
- Rewrite (N,
- Build_Call_With_Task (Pref, RTE (RE_Terminated)));
- end if;
-
- Analyze_And_Resolve (N, Standard_Boolean);
- end Terminated;
-
- ----------------
- -- To_Address --
- ----------------
-
- -- Transforms System'To_Address (X) into unchecked conversion
- -- from (integral) type of X to type address.
-
- when Attribute_To_Address =>
- Rewrite (N,
- Unchecked_Convert_To (RTE (RE_Address),
- Relocate_Node (First (Exprs))));
- Analyze_And_Resolve (N, RTE (RE_Address));
-
- ----------------
- -- Truncation --
- ----------------
-
- -- Transforms 'Truncation into a call to the floating-point attribute
- -- function Truncation in Fat_xxx (where xxx is the root type)
-
- when Attribute_Truncation =>
- Expand_Fpt_Attribute_R (N);
-
- -----------------------
- -- Unbiased_Rounding --
- -----------------------
-
- -- Transforms 'Unbiased_Rounding into a call to the floating-point
- -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
- -- root type)
-
- when Attribute_Unbiased_Rounding =>
- Expand_Fpt_Attribute_R (N);
-
- ----------------------
- -- Unchecked_Access --
- ----------------------
-
- when Attribute_Unchecked_Access =>
- Expand_Access_To_Type (N);
-
- -----------------
- -- UET_Address --
- -----------------
-
- when Attribute_UET_Address => UET_Address : declare
- Ent : constant Entity_Id :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
-
- begin
- Insert_Action (N,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent,
- Aliased_Present => True,
- Object_Definition =>
- New_Occurrence_Of (RTE (RE_Address), Loc)));
-
- -- Construct name __gnat_xxx__SDP, where xxx is the unit name
- -- in normal external form.
-
- Get_External_Unit_Name_String (Get_Unit_Name (Pref));
- Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
- Name_Len := Name_Len + 7;
- Name_Buffer (1 .. 7) := "__gnat_";
- Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
- Name_Len := Name_Len + 5;
-
- Set_Is_Imported (Ent);
- Set_Interface_Name (Ent,
- Make_String_Literal (Loc,
- Strval => String_From_Name_Buffer));
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ent, Loc),
- Attribute_Name => Name_Address));
-
- Analyze_And_Resolve (N, Typ);
- end UET_Address;
-
- -------------------------
- -- Unrestricted_Access --
- -------------------------
-
- when Attribute_Unrestricted_Access =>
- Expand_Access_To_Type (N);
-
- ---------------
- -- VADS_Size --
- ---------------
-
- -- The processing for VADS_Size is shared with Size
-
- ---------
- -- Val --
- ---------
-
- -- For enumeration types with a standard representation, and for all
- -- other types, Val is handled by Gigi. For enumeration types with
- -- a non-standard representation we use the _Pos_To_Rep array that
- -- was created when the type was frozen.
-
- when Attribute_Val => Val :
- declare
- Etyp : constant Entity_Id := Base_Type (Entity (Pref));
-
- begin
- if Is_Enumeration_Type (Etyp)
- and then Present (Enum_Pos_To_Rep (Etyp))
- then
- Rewrite (N,
- Make_Indexed_Component (Loc,
- Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
- Expressions => New_List (
- Convert_To (Standard_Integer,
- Relocate_Node (First (Exprs))))));
-
- Analyze_And_Resolve (N, Typ);
- end if;
- end Val;
-
- -----------
- -- Valid --
- -----------
-
- -- The code for valid is dependent on the particular types involved.
- -- See separate sections below for the generated code in each case.
-
- when Attribute_Valid => Valid :
- declare
- Ptyp : constant Entity_Id := Etype (Pref);
- Btyp : Entity_Id := Base_Type (Ptyp);
- Tst : Node_Id;
-
- function Make_Range_Test return Node_Id;
- -- Build the code for a range test of the form
- -- Btyp!(Pref) >= Btyp!(Ptyp'First)
- -- and then
- -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
-
- function Make_Range_Test return Node_Id is
- begin
- return
- Make_And_Then (Loc,
- Left_Opnd =>
- Make_Op_Ge (Loc,
- Left_Opnd =>
- Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
-
- Right_Opnd =>
- Unchecked_Convert_To (Btyp,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ptyp, Loc),
- Attribute_Name => Name_First))),
-
- Right_Opnd =>
- Make_Op_Le (Loc,
- Left_Opnd =>
- Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
-
- Right_Opnd =>
- Unchecked_Convert_To (Btyp,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ptyp, Loc),
- Attribute_Name => Name_Last))));
- end Make_Range_Test;
-
- -- Start of processing for Attribute_Valid
-
- begin
- -- Floating-point case. This case is handled by the Valid attribute
- -- code in the floating-point attribute run-time library.
-
- if Is_Floating_Point_Type (Ptyp) then
- declare
- Rtp : constant Entity_Id := Root_Type (Etype (Pref));
-
- begin
- Expand_Fpt_Attribute (N, Rtp, New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Unchecked_Convert_To (Rtp, Pref),
- Attribute_Name => Name_Unrestricted_Access)));
-
- -- One more task, we still need a range check. Required
- -- only if we have a constraint, since the Valid routine
- -- catches infinities properly (infinities are never valid).
-
- -- The way we do the range check is simply to create the
- -- expression: Valid (N) and then Base_Type(Pref) in Typ.
-
- if not Subtypes_Statically_Match (Ptyp, Btyp) then
- Rewrite (N,
- Make_And_Then (Loc,
- Left_Opnd => Relocate_Node (N),
- Right_Opnd =>
- Make_In (Loc,
- Left_Opnd => Convert_To (Btyp, Pref),
- Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
- end if;
- end;
-
- -- Enumeration type with holes
-
- -- For enumeration types with holes, the Pos value constructed by
- -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
- -- second argument of False returns minus one for an invalid value,
- -- and the non-negative pos value for a valid value, so the
- -- expansion of X'Valid is simply:
-
- -- type(X)'Pos (X) >= 0
-
- -- We can't quite generate it that way because of the requirement
- -- for the non-standard second argument of False, so we have to
- -- explicitly create:
-
- -- _rep_to_pos (X, False) >= 0
-
- -- If we have an enumeration subtype, we also check that the
- -- value is in range:
-
- -- _rep_to_pos (X, False) >= 0
- -- and then
- -- (X >= type(X)'First and then type(X)'Last <= X)
-
- elsif Is_Enumeration_Type (Ptyp)
- and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
- then
- Tst :=
- Make_Op_Ge (Loc,
- Left_Opnd =>
- Make_Function_Call (Loc,
- Name =>
- New_Reference_To
- (TSS (Base_Type (Ptyp), Name_uRep_To_Pos), Loc),
- Parameter_Associations => New_List (
- Pref,
- New_Occurrence_Of (Standard_False, Loc))),
- Right_Opnd => Make_Integer_Literal (Loc, 0));
-
- if Ptyp /= Btyp
- and then
- (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
- or else
- Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
- then
- -- The call to Make_Range_Test will create declarations
- -- that need a proper insertion point, but Pref is now
- -- attached to a node with no ancestor. Attach to tree
- -- even if it is to be rewritten below.
-
- Set_Parent (Tst, Parent (N));
-
- Tst :=
- Make_And_Then (Loc,
- Left_Opnd => Make_Range_Test,
- Right_Opnd => Tst);
- end if;
-
- Rewrite (N, Tst);
-
- -- Fortran convention booleans
-
- -- For the very special case of Fortran convention booleans, the
- -- value is always valid, since it is an integer with the semantics
- -- that non-zero is true, and any value is permissible.
-
- elsif Is_Boolean_Type (Ptyp)
- and then Convention (Ptyp) = Convention_Fortran
- then
- Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
-
- -- For biased representations, we will be doing an unchecked
- -- conversion without unbiasing the result. That means that
- -- the range test has to take this into account, and the
- -- proper form of the test is:
-
- -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
-
- elsif Has_Biased_Representation (Ptyp) then
- Btyp := RTE (RE_Unsigned_32);
- Rewrite (N,
- Make_Op_Lt (Loc,
- Left_Opnd =>
- Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
- Right_Opnd =>
- Unchecked_Convert_To (Btyp,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ptyp, Loc),
- Attribute_Name => Name_Range_Length))));
-
- -- For all other scalar types, what we want logically is a
- -- range test:
-
- -- X in type(X)'First .. type(X)'Last
-
- -- But that's precisely what won't work because of possible
- -- unwanted optimization (and indeed the basic motivation for
- -- the Valid attribute -is exactly that this test does not work.
- -- What will work is:
-
- -- Btyp!(X) >= Btyp!(type(X)'First)
- -- and then
- -- Btyp!(X) <= Btyp!(type(X)'Last)
-
- -- where Btyp is an integer type large enough to cover the full
- -- range of possible stored values (i.e. it is chosen on the basis
- -- of the size of the type, not the range of the values). We write
- -- this as two tests, rather than a range check, so that static
- -- evaluation will easily remove either or both of the checks if
- -- they can be -statically determined to be true (this happens
- -- when the type of X is static and the range extends to the full
- -- range of stored values).
-
- -- Unsigned types. Note: it is safe to consider only whether the
- -- subtype is unsigned, since we will in that case be doing all
- -- unsigned comparisons based on the subtype range. Since we use
- -- the actual subtype object size, this is appropriate.
-
- -- For example, if we have
-
- -- subtype x is integer range 1 .. 200;
- -- for x'Object_Size use 8;
-
- -- Now the base type is signed, but objects of this type are 8
- -- bits unsigned, and doing an unsigned test of the range 1 to
- -- 200 is correct, even though a value greater than 127 looks
- -- signed to a signed comparison.
-
- elsif Is_Unsigned_Type (Ptyp) then
- if Esize (Ptyp) <= 32 then
- Btyp := RTE (RE_Unsigned_32);
- else
- Btyp := RTE (RE_Unsigned_64);
- end if;
-
- Rewrite (N, Make_Range_Test);
-
- -- Signed types
-
- else
- if Esize (Ptyp) <= Esize (Standard_Integer) then
- Btyp := Standard_Integer;
- else
- Btyp := Universal_Integer;
- end if;
-
- Rewrite (N, Make_Range_Test);
- end if;
-
- Analyze_And_Resolve (N, Standard_Boolean);
- end Valid;
-
- -----------
- -- Value --
- -----------
-
- -- Value attribute is handled in separate unti Exp_Imgv
-
- when Attribute_Value =>
- Exp_Imgv.Expand_Value_Attribute (N);
-
- -----------------
- -- Value_Size --
- -----------------
-
- -- The processing for Value_Size shares the processing for Size
-
- -------------
- -- Version --
- -------------
-
- -- The processing for Version shares the processing for Body_Version
-
- ----------------
- -- Wide_Image --
- ----------------
-
- -- We expand typ'Wide_Image (X) into
-
- -- String_To_Wide_String
- -- (typ'Image (X), Wide_Character_Encoding_Method)
-
- -- This works in all cases because String_To_Wide_String converts any
- -- wide character escape sequences resulting from the Image call to the
- -- proper Wide_Character equivalent
-
- -- not quite right for typ = Wide_Character ???
-
- when Attribute_Wide_Image => Wide_Image :
- begin
- Rewrite (N,
- Make_Function_Call (Loc,
- Name => New_Reference_To (RTE (RE_String_To_Wide_String), Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Pref,
- Attribute_Name => Name_Image,
- Expressions => Exprs),
-
- Make_Integer_Literal (Loc,
- Intval => Int (Wide_Character_Encoding_Method)))));
-
- Analyze_And_Resolve (N, Standard_Wide_String);
- end Wide_Image;
-
- ----------------
- -- Wide_Value --
- ----------------
-
- -- We expand typ'Wide_Value (X) into
-
- -- typ'Value
- -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
-
- -- Wide_String_To_String is a runtime function that converts its wide
- -- string argument to String, converting any non-translatable characters
- -- into appropriate escape sequences. This preserves the required
- -- semantics of Wide_Value in all cases, and results in a very simple
- -- implementation approach.
-
- -- It's not quite right where typ = Wide_Character, because the encoding
- -- method may not cover the whole character type ???
-
- when Attribute_Wide_Value => Wide_Value :
- begin
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => Pref,
- Attribute_Name => Name_Value,
-
- Expressions => New_List (
- Make_Function_Call (Loc,
- Name =>
- New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
-
- Parameter_Associations => New_List (
- Relocate_Node (First (Exprs)),
- Make_Integer_Literal (Loc,
- Intval => Int (Wide_Character_Encoding_Method)))))));
-
- Analyze_And_Resolve (N, Typ);
- end Wide_Value;
-
- ----------------
- -- Wide_Width --
- ----------------
-
- -- Wide_Width attribute is handled in separate unit Exp_Imgv
-
- when Attribute_Wide_Width =>
- Exp_Imgv.Expand_Width_Attribute (N, Wide => True);
-
- -----------
- -- Width --
- -----------
-
- -- Width attribute is handled in separate unit Exp_Imgv
-
- when Attribute_Width =>
- Exp_Imgv.Expand_Width_Attribute (N, Wide => False);
-
- -----------
- -- Write --
- -----------
-
- when Attribute_Write => Write : declare
- P_Type : constant Entity_Id := Entity (Pref);
- U_Type : constant Entity_Id := Underlying_Type (P_Type);
- Pname : Entity_Id;
- Decl : Node_Id;
- Prag : Node_Id;
- Arg3 : Node_Id;
- Wfunc : Node_Id;
-
- begin
- -- If no underlying type, we have an error that will be diagnosed
- -- elsewhere, so here we just completely ignore the expansion.
-
- if No (U_Type) then
- return;
- end if;
-
- -- The simple case, if there is a TSS for Write, just call it
-
- Pname := Find_Inherited_TSS (P_Type, Name_uWrite);
-
- if Present (Pname) then
- null;
-
- else
- -- If there is a Stream_Convert pragma, use it, we rewrite
-
- -- sourcetyp'Output (stream, Item)
-
- -- as
-
- -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
-
- -- where strmwrite is the given Write function that converts
- -- an argument of type sourcetyp or a type acctyp, from which
- -- it is derived to type strmtyp. The conversion to acttyp is
- -- required for the derived case.
-
- Prag :=
- Get_Rep_Pragma
- (Implementation_Base_Type (P_Type), Name_Stream_Convert);
-
- if Present (Prag) then
- Arg3 :=
- Next (Next (First (Pragma_Argument_Associations (Prag))));
- Wfunc := Entity (Expression (Arg3));
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
- Attribute_Name => Name_Output,
- Expressions => New_List (
- Relocate_Node (First (Exprs)),
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Wfunc, Loc),
- Parameter_Associations => New_List (
- Convert_To (Etype (First_Formal (Wfunc)),
- Relocate_Node (Next (First (Exprs)))))))));
-
- Analyze (N);
- return;
-
- -- For elementary types, we call the W_xxx routine directly
-
- elsif Is_Elementary_Type (U_Type) then
- Rewrite (N, Build_Elementary_Write_Call (N));
- Analyze (N);
- return;
-
- -- Array type case
-
- elsif Is_Array_Type (U_Type) then
- Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
- Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
-
- -- Tagged type case, use the primitive Write function. Note that
- -- this will dispatch in the class-wide case which is what we want
-
- elsif Is_Tagged_Type (U_Type) then
- Pname := Find_Prim_Op (U_Type, Name_uWrite);
-
- -- All other record type cases, including protected records.
- -- The latter only arise for expander generated code for
- -- handling shared passive partition access.
-
- else
- pragma Assert
- (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-
- if Has_Discriminants (U_Type)
- and then Present
- (Discriminant_Default_Value (First_Discriminant (U_Type)))
- then
- Build_Mutable_Record_Write_Procedure
- (Loc, Base_Type (U_Type), Decl, Pname);
-
- else
- Build_Record_Write_Procedure
- (Loc, Base_Type (U_Type), Decl, Pname);
- end if;
-
- Insert_Action (N, Decl);
- end if;
- end if;
-
- -- If we fall through, Pname is the procedure to be called
-
- Rewrite_Stream_Proc_Call (Pname);
- end Write;
-
- -- Component_Size is handled by Gigi, unless the component size is
- -- known at compile time, which is always true in the packed array
- -- case. It is important that the packed array case is handled in
- -- the front end (see Eval_Attribute) since Gigi would otherwise
- -- get confused by the equivalent packed array type.
-
- when Attribute_Component_Size =>
- null;
-
- -- The following attributes are handled by Gigi (except that static
- -- cases have already been evaluated by the semantics, but in any
- -- case Gigi should not count on that).
-
- -- In addition Gigi handles the non-floating-point cases of Pred
- -- and Succ (including the fixed-point cases, which can just be
- -- treated as integer increment/decrement operations)
-
- -- Gigi also handles the non-class-wide cases of Size
-
- when Attribute_Bit_Order |
- Attribute_Code_Address |
- Attribute_Definite |
- Attribute_Max |
- Attribute_Mechanism_Code |
- Attribute_Min |
- Attribute_Null_Parameter |
- Attribute_Passed_By_Reference =>
- null;
-
- -- The following attributes are also handled by Gigi, but return a
- -- universal integer result, so may need a conversion for checking
- -- that the result is in range.
-
- when Attribute_Aft |
- Attribute_Alignment |
- Attribute_Bit |
- Attribute_Max_Size_In_Storage_Elements
- =>
- Apply_Universal_Integer_Attribute_Checks (N);
-
- -- The following attributes should not appear at this stage, since they
- -- have already been handled by the analyzer (and properly rewritten
- -- with corresponding values or entities to represent the right values)
-
- when Attribute_Abort_Signal |
- Attribute_Address_Size |
- Attribute_Base |
- Attribute_Class |
- Attribute_Default_Bit_Order |
- Attribute_Delta |
- Attribute_Denorm |
- Attribute_Digits |
- Attribute_Emax |
- Attribute_Epsilon |
- Attribute_Has_Discriminants |
- Attribute_Large |
- Attribute_Machine_Emax |
- Attribute_Machine_Emin |
- Attribute_Machine_Mantissa |
- Attribute_Machine_Overflows |
- Attribute_Machine_Radix |
- Attribute_Machine_Rounds |
- Attribute_Max_Interrupt_Priority |
- Attribute_Max_Priority |
- Attribute_Maximum_Alignment |
- Attribute_Model_Emin |
- Attribute_Model_Epsilon |
- Attribute_Model_Mantissa |
- Attribute_Model_Small |
- Attribute_Modulus |
- Attribute_Partition_ID |
- Attribute_Range |
- Attribute_Safe_Emax |
- Attribute_Safe_First |
- Attribute_Safe_Large |
- Attribute_Safe_Last |
- Attribute_Safe_Small |
- Attribute_Scale |
- Attribute_Signed_Zeros |
- Attribute_Small |
- Attribute_Storage_Unit |
- Attribute_Tick |
- Attribute_Type_Class |
- Attribute_Universal_Literal_String |
- Attribute_Wchar_T_Size |
- Attribute_Word_Size =>
-
- raise Program_Error;
-
- -- The Asm_Input and Asm_Output attributes are not expanded at this
- -- stage, but will be eliminated in the expansion of the Asm call,
- -- see Exp_Intr for details. So Gigi will never see these either.
-
- when Attribute_Asm_Input |
- Attribute_Asm_Output =>
-
- null;
-
- end case;
-
- end Expand_N_Attribute_Reference;
-
- ----------------------
- -- Expand_Pred_Succ --
- ----------------------
-
- -- For typ'Pred (exp), we generate the check
-
- -- [constraint_error when exp = typ'Base'First]
-
- -- Similarly, for typ'Succ (exp), we generate the check
-
- -- [constraint_error when exp = typ'Base'Last]
-
- -- These checks are not generated for modular types, since the proper
- -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
-
- procedure Expand_Pred_Succ (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Cnam : Name_Id;
-
- begin
- if Attribute_Name (N) = Name_Pred then
- Cnam := Name_First;
- else
- Cnam := Name_Last;
- end if;
-
- Insert_Action (N,
- Make_Raise_Constraint_Error (Loc,
- Condition =>
- Make_Op_Eq (Loc,
- Left_Opnd => Duplicate_Subexpr (First (Expressions (N))),
- Right_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
- Attribute_Name => Cnam))));
-
- end Expand_Pred_Succ;
-
- ------------------------
- -- Find_Inherited_TSS --
- ------------------------
-
- function Find_Inherited_TSS
- (Typ : Entity_Id;
- Nam : Name_Id) return Entity_Id
- is
- P_Type : Entity_Id := Typ;
- Proc : Entity_Id;
-
- begin
- Proc := TSS (Base_Type (Typ), Nam);
-
- -- Check first if there is a TSS given for the type itself.
-
- if Present (Proc) then
- return Proc;
- end if;
-
- -- If Typ is a derived type, it may inherit attributes from some
- -- ancestor which is not the ultimate underlying one.
-
- if Is_Derived_Type (P_Type) then
-
- while Is_Derived_Type (P_Type) loop
- Proc := TSS (Base_Type (Etype (Typ)), Nam);
-
- if Present (Proc) then
- return Proc;
- else
- P_Type := Base_Type (Etype (P_Type));
- end if;
- end loop;
- end if;
-
- -- If nothing else, use the TSS of the root type.
-
- return TSS (Base_Type (Underlying_Type (Typ)), Nam);
- end Find_Inherited_TSS;
-
- -----------------------
- -- Get_Index_Subtype --
- -----------------------
-
- function Get_Index_Subtype (N : Node_Id) return Node_Id is
- P_Type : Entity_Id := Etype (Prefix (N));
- Indx : Node_Id;
- J : Int;
-
- begin
- if Is_Access_Type (P_Type) then
- P_Type := Designated_Type (P_Type);
- end if;
-
- if No (Expressions (N)) then
- J := 1;
- else
- J := UI_To_Int (Expr_Value (First (Expressions (N))));
- end if;
-
- Indx := First_Index (P_Type);
- while J > 1 loop
- Next_Index (Indx);
- J := J - 1;
- end loop;
-
- return Etype (Indx);
- end Get_Index_Subtype;
-
- ---------------------------------
- -- Is_Constrained_Packed_Array --
- ---------------------------------
-
- function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
- Arr : Entity_Id := Typ;
-
- begin
- if Is_Access_Type (Arr) then
- Arr := Designated_Type (Arr);
- end if;
-
- return Is_Array_Type (Arr)
- and then Is_Constrained (Arr)
- and then Present (Packed_Array_Type (Arr));
- end Is_Constrained_Packed_Array;
-
-end Exp_Attr;
projects / msp430-gcc.git / blobdiff