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+------------------------------------------------------------------------------
+-- --
+-- GNAT COMPILER COMPONENTS --
+-- --
+-- E X P _ A T T R --
+-- --
+-- B o d y --
+-- --
+-- Copyright (C) 1992-2013, Free Software Foundation, Inc. --
+-- --
+-- GNAT is free software; you can redistribute it and/or modify it under --
+-- terms of the GNU General Public License as published by the Free Soft- --
+-- ware Foundation; either version 3, or (at your option) any later ver- --
+-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
+-- for more details. You should have received a copy of the GNU General --
+-- Public License distributed with GNAT; see file COPYING3. If not, go to --
+-- http://www.gnu.org/licenses for a complete copy of the license. --
+-- --
+-- GNAT was originally developed by the GNAT team at New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc. --
+-- --
+------------------------------------------------------------------------------
+
+with Atree; use Atree;
+with Checks; use Checks;
+with Einfo; use Einfo;
+with Elists; use Elists;
+with Exp_Atag; use Exp_Atag;
+with Exp_Ch2; use Exp_Ch2;
+with Exp_Ch3; use Exp_Ch3;
+with Exp_Ch6; use Exp_Ch6;
+with Exp_Ch9; use Exp_Ch9;
+with Exp_Dist; use Exp_Dist;
+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 Exp_VFpt; use Exp_VFpt;
+with Fname; use Fname;
+with Freeze; use Freeze;
+with Gnatvsn; use Gnatvsn;
+with Itypes; use Itypes;
+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 Rident; use Rident;
+with Rtsfind; use Rtsfind;
+with Sem; use Sem;
+with Sem_Aux; use Sem_Aux;
+with Sem_Ch6; use Sem_Ch6;
+with Sem_Ch7; use Sem_Ch7;
+with Sem_Ch8; use Sem_Ch8;
+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 Targparm; use Targparm;
+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 --
+ -----------------------
+
+ function Build_Array_VS_Func
+ (A_Type : Entity_Id;
+ Nod : Node_Id) return Entity_Id;
+ -- Build function to test Valid_Scalars for array type A_Type. Nod is the
+ -- Valid_Scalars attribute node, used to insert the function body, and the
+ -- value returned is the entity of the constructed function body. We do not
+ -- bother to generate a separate spec for this subprogram.
+
+ 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. indexes) 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_Access_To_Protected_Op
+ (N : Node_Id;
+ Pref : Node_Id;
+ Typ : Entity_Id);
+ -- An attribute reference to a protected subprogram is transformed into
+ -- a pair of pointers: one to the object, and one to the operations.
+ -- This expansion is performed for 'Access and for 'Unrestricted_Access.
+
+ procedure Expand_Fpt_Attribute
+ (N : Node_Id;
+ Pkg : RE_Id;
+ Nam : Name_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. Pkg identifies the package containing
+ -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
+ -- have already been converted to the floating-point type for which Pkg was
+ -- instantiated. The Nam argument is the relevant attribute processing
+ -- routine to be called. This is the same as the attribute name, except in
+ -- the Unaligned_Valid case.
+
+ 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. The function to be called
+ -- is always the same as the attribute name.
+
+ 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. The
+ -- function to be called is always the same as the attribute name.
+
+ 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. The function to be called
+ -- is always the same as the attribute name.
+
+ procedure Expand_Pred_Succ (N : Node_Id);
+ -- Handles expansion of Pred or Succ attributes for case of non-real
+ -- operand with overflow checking required.
+
+ procedure Expand_Update_Attribute (N : Node_Id);
+ -- Handle the expansion of attribute Update
+
+ 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 Find_Fat_Info
+ (T : Entity_Id;
+ Fat_Type : out Entity_Id;
+ Fat_Pkg : out RE_Id);
+ -- Given a floating-point type T, identifies the package containing the
+ -- attributes for this type (returned in Fat_Pkg), and the corresponding
+ -- type for which this package was instantiated from Fat_Gen. Error if T
+ -- is not a floating-point type.
+
+ function Find_Stream_Subprogram
+ (Typ : Entity_Id;
+ Nam : TSS_Name_Type) return Entity_Id;
+ -- Returns the stream-oriented subprogram attribute for Typ. For tagged
+ -- types, the corresponding primitive operation is looked up, else the
+ -- appropriate TSS from the type itself, or from its closest ancestor
+ -- defining it, is returned. In both cases, inheritance of representation
+ -- aspects is thus taken into account.
+
+ function Full_Base (T : Entity_Id) return Entity_Id;
+ -- The stream functions need to examine the underlying representation of
+ -- composite types. In some cases T may be non-private but its base type
+ -- is, in which case the function returns the corresponding full view.
+
+ function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
+ -- Given a type, find a corresponding stream convert pragma that applies to
+ -- the implementation base type of this type (Typ). If found, return the
+ -- pragma node, otherwise return Empty if no pragma is found.
+
+ 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.
+
+ function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
+ -- Returns true iff the given node refers to an attribute call that
+ -- can be expanded directly by the back end and does not need front end
+ -- expansion. Typically used for rounding and truncation attributes that
+ -- appear directly inside a conversion to integer.
+
+ -------------------------
+ -- Build_Array_VS_Func --
+ -------------------------
+
+ function Build_Array_VS_Func
+ (A_Type : Entity_Id;
+ Nod : Node_Id) return Entity_Id
+ is
+ Loc : constant Source_Ptr := Sloc (Nod);
+ Comp_Type : constant Entity_Id := Component_Type (A_Type);
+ Body_Stmts : List_Id;
+ Index_List : List_Id;
+ Func_Id : Entity_Id;
+ Formals : List_Id;
+
+ function Test_Component return List_Id;
+ -- Create one statement to test validity of one component designated by
+ -- a full set of indexes. Returns statement list containing test.
+
+ function Test_One_Dimension (N : Int) return List_Id;
+ -- Create loop to test one dimension of the array. The single statement
+ -- in the loop body tests the inner dimensions if any, or else the
+ -- single component. Note that this procedure is called recursively,
+ -- with N being the dimension to be initialized. A call with N greater
+ -- than the number of dimensions simply generates the component test,
+ -- terminating the recursion. Returns statement list containing tests.
+
+ --------------------
+ -- Test_Component --
+ --------------------
+
+ function Test_Component return List_Id is
+ Comp : Node_Id;
+ Anam : Name_Id;
+
+ begin
+ Comp :=
+ Make_Indexed_Component (Loc,
+ Prefix => Make_Identifier (Loc, Name_uA),
+ Expressions => Index_List);
+
+ if Is_Scalar_Type (Comp_Type) then
+ Anam := Name_Valid;
+ else
+ Anam := Name_Valid_Scalars;
+ end if;
+
+ return New_List (
+ Make_If_Statement (Loc,
+ Condition =>
+ Make_Op_Not (Loc,
+ Right_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Anam,
+ Prefix => Comp)),
+ Then_Statements => New_List (
+ Make_Simple_Return_Statement (Loc,
+ Expression => New_Occurrence_Of (Standard_False, Loc)))));
+ end Test_Component;
+
+ ------------------------
+ -- Test_One_Dimension --
+ ------------------------
+
+ function Test_One_Dimension (N : Int) return List_Id is
+ Index : Entity_Id;
+
+ begin
+ -- If all dimensions dealt with, we simply test the component
+
+ if N > Number_Dimensions (A_Type) then
+ return Test_Component;
+
+ -- Here we generate the required loop
+
+ else
+ Index :=
+ Make_Defining_Identifier (Loc, New_External_Name ('J', N));
+
+ Append (New_Reference_To (Index, Loc), Index_List);
+
+ return New_List (
+ Make_Implicit_Loop_Statement (Nod,
+ Identifier => Empty,
+ Iteration_Scheme =>
+ Make_Iteration_Scheme (Loc,
+ Loop_Parameter_Specification =>
+ Make_Loop_Parameter_Specification (Loc,
+ Defining_Identifier => Index,
+ Discrete_Subtype_Definition =>
+ Make_Attribute_Reference (Loc,
+ Prefix => Make_Identifier (Loc, Name_uA),
+ Attribute_Name => Name_Range,
+ Expressions => New_List (
+ Make_Integer_Literal (Loc, N))))),
+ Statements => Test_One_Dimension (N + 1)),
+ Make_Simple_Return_Statement (Loc,
+ Expression => New_Occurrence_Of (Standard_True, Loc)));
+ end if;
+ end Test_One_Dimension;
+
+ -- Start of processing for Build_Array_VS_Func
+
+ begin
+ Index_List := New_List;
+ Func_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
+
+ Body_Stmts := Test_One_Dimension (1);
+
+ -- Parameter is always (A : A_Typ)
+
+ Formals := New_List (
+ Make_Parameter_Specification (Loc,
+ Defining_Identifier => Make_Defining_Identifier (Loc, Name_uA),
+ In_Present => True,
+ Out_Present => False,
+ Parameter_Type => New_Reference_To (A_Type, Loc)));
+
+ -- Build body
+
+ Set_Ekind (Func_Id, E_Function);
+ Set_Is_Internal (Func_Id);
+
+ Insert_Action (Nod,
+ Make_Subprogram_Body (Loc,
+ Specification =>
+ Make_Function_Specification (Loc,
+ Defining_Unit_Name => Func_Id,
+ Parameter_Specifications => Formals,
+ Result_Definition =>
+ New_Occurrence_Of (Standard_Boolean, Loc)),
+ Declarations => New_List,
+ Handled_Statement_Sequence =>
+ Make_Handled_Sequence_Of_Statements (Loc,
+ Statements => Body_Stmts)));
+
+ if not Debug_Generated_Code then
+ Set_Debug_Info_Off (Func_Id);
+ end if;
+
+ return Func_Id;
+ end Build_Array_VS_Func;
+
+ ----------------------------------
+ -- 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
+ Push_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.
+
+ Push_Scope (Curr);
+ end if;
+
+ if Check then
+ Insert_Action (N, Decl);
+ else
+ Insert_Action (N, Decl, Suppress => 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_Protected_Op --
+ -----------------------------------
+
+ procedure Expand_Access_To_Protected_Op
+ (N : Node_Id;
+ Pref : Node_Id;
+ Typ : Entity_Id)
+ is
+ -- 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.
+
+ Loc : constant Source_Ptr := Sloc (N);
+ Agg : Node_Id;
+ Btyp : constant Entity_Id := Base_Type (Typ);
+ Sub : Entity_Id;
+ Sub_Ref : Node_Id;
+ E_T : constant Entity_Id := Equivalent_Type (Btyp);
+ Acc : constant Entity_Id :=
+ Etype (Next_Component (First_Component (E_T)));
+ Obj_Ref : Node_Id;
+ Curr : Entity_Id;
+
+ function May_Be_External_Call return Boolean;
+ -- If the 'Access is to a local operation, but appears in a context
+ -- where it may lead to a call from outside the object, we must treat
+ -- this as an external call. Clearly we cannot tell without full
+ -- flow analysis, and a subsequent call that uses this 'Access may
+ -- lead to a bounded error (trying to seize locks twice, e.g.). For
+ -- now we treat 'Access as a potential external call if it is an actual
+ -- in a call to an outside subprogram.
+
+ --------------------------
+ -- May_Be_External_Call --
+ --------------------------
+
+ function May_Be_External_Call return Boolean is
+ Subp : Entity_Id;
+ Par : Node_Id := Parent (N);
+
+ begin
+ -- Account for the case where the Access attribute is part of a
+ -- named parameter association.
+
+ if Nkind (Par) = N_Parameter_Association then
+ Par := Parent (Par);
+ end if;
+
+ if Nkind (Par) in N_Subprogram_Call
+ and then Is_Entity_Name (Name (Par))
+ then
+ Subp := Entity (Name (Par));
+ return not In_Open_Scopes (Scope (Subp));
+ else
+ return False;
+ end if;
+ end May_Be_External_Call;
+
+ -- Start of processing for Expand_Access_To_Protected_Op
+
+ 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
+ if May_Be_External_Call then
+ Sub :=
+ New_Occurrence_Of (External_Subprogram (Entity (Pref)), Loc);
+ else
+ Sub :=
+ New_Occurrence_Of
+ (Protected_Body_Subprogram (Entity (Pref)), Loc);
+ end if;
+
+ -- Don't traverse the scopes when the attribute occurs within an init
+ -- proc, because we directly use the _init formal of the init proc in
+ -- that case.
+
+ Curr := Current_Scope;
+ if not Is_Init_Proc (Curr) then
+ pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
+
+ while Scope (Curr) /= Scope (Entity (Pref)) loop
+ Curr := Scope (Curr);
+ end loop;
+ end if;
+
+ -- In case of protected entries the first formal of its Protected_
+ -- Body_Subprogram is the address of the object.
+
+ if Ekind (Curr) = E_Entry then
+ Obj_Ref :=
+ New_Occurrence_Of
+ (First_Formal
+ (Protected_Body_Subprogram (Curr)), Loc);
+
+ -- If the current scope is an init proc, then use the address of the
+ -- _init formal as the object reference.
+
+ elsif Is_Init_Proc (Curr) then
+ Obj_Ref :=
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
+ Attribute_Name => Name_Address);
+
+ -- In case of protected subprograms the first formal of its
+ -- Protected_Body_Subprogram is the object and we get its address.
+
+ else
+ Obj_Ref :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Occurrence_Of
+ (First_Formal
+ (Protected_Body_Subprogram (Curr)), Loc),
+ Attribute_Name => Name_Address);
+ end if;
+
+ -- 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;
+
+ Sub_Ref :=
+ Make_Attribute_Reference (Loc,
+ Prefix => Sub,
+ Attribute_Name => Name_Access);
+
+ -- We set the type of the access reference to the already generated
+ -- access_to_subprogram type, and declare the reference analyzed, to
+ -- prevent further expansion when the enclosing aggregate is analyzed.
+
+ Set_Etype (Sub_Ref, Acc);
+ Set_Analyzed (Sub_Ref);
+
+ Agg :=
+ Make_Aggregate (Loc,
+ Expressions => New_List (Obj_Ref, Sub_Ref));
+
+ -- Sub_Ref has been marked as analyzed, but we still need to make sure
+ -- Sub is correctly frozen.
+
+ Freeze_Before (N, Entity (Sub));
+
+ Rewrite (N, Agg);
+ Analyze_And_Resolve (N, E_T);
+
+ -- 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 Expand_Access_To_Protected_Op;
+
+ --------------------------
+ -- Expand_Fpt_Attribute --
+ --------------------------
+
+ procedure Expand_Fpt_Attribute
+ (N : Node_Id;
+ Pkg : RE_Id;
+ Nam : Name_Id;
+ Args : List_Id)
+ is
+ Loc : constant Source_Ptr := Sloc (N);
+ Typ : constant Entity_Id := Etype (N);
+ Fnm : Node_Id;
+
+ begin
+ -- The function name is the selected component Attr_xxx.yyy where
+ -- Attr_xxx is the package name, and yyy is the argument Nam.
+
+ -- 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!
+
+ Fnm :=
+ Make_Selected_Component (Loc,
+ Prefix => New_Reference_To (RTE (Pkg), Loc),
+ Selector_Name => Make_Identifier (Loc, Nam));
+
+ -- The generated call is given the provided set of parameters, and then
+ -- wrapped in a conversion which converts the result to the target type
+ -- We use the base type as the target because a range check may be
+ -- required.
+
+ Rewrite (N,
+ Unchecked_Convert_To (Base_Type (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));
+ Ftp : Entity_Id;
+ Pkg : RE_Id;
+ begin
+ Find_Fat_Info (Etype (E1), Ftp, Pkg);
+ Expand_Fpt_Attribute
+ (N, Pkg, Attribute_Name (N),
+ New_List (Unchecked_Convert_To (Ftp, 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));
+ Ftp : Entity_Id;
+ Pkg : RE_Id;
+ E2 : constant Node_Id := Next (E1);
+ begin
+ Find_Fat_Info (Etype (E1), Ftp, Pkg);
+ Expand_Fpt_Attribute
+ (N, Pkg, Attribute_Name (N),
+ New_List (
+ Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
+ Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
+ end Expand_Fpt_Attribute_RI;
+
+ -----------------------------
+ -- Expand_Fpt_Attribute_RR --
+ -----------------------------
+
+ -- The two arguments are 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));
+ Ftp : Entity_Id;
+ Pkg : RE_Id;
+ E2 : constant Node_Id := Next (E1);
+ begin
+ Find_Fat_Info (Etype (E1), Ftp, Pkg);
+ Expand_Fpt_Attribute
+ (N, Pkg, Attribute_Name (N),
+ New_List (
+ Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
+ Unchecked_Convert_To (Ftp, 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);
+ Ptyp : constant Entity_Id := Etype (Pref);
+ 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 : constant Entity_Id := Next_Formal (First_Formal (Pname));
+ Formal_Typ : constant Entity_Id := Etype (Formal);
+ Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
+
+ begin
+ -- The expansion depends on Item, the second actual, which is
+ -- the object being streamed in or out.
+
+ -- If the item is a component of a packed array type, and
+ -- a conversion is needed on exit, we introduce a temporary to
+ -- hold the value, because otherwise the packed reference will
+ -- not be properly expanded.
+
+ if Nkind (Item) = N_Indexed_Component
+ and then Is_Packed (Base_Type (Etype (Prefix (Item))))
+ and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
+ and then Is_Written
+ then
+ declare
+ Temp : constant Entity_Id := Make_Temporary (Loc, 'V');
+ Decl : Node_Id;
+ Assn : Node_Id;
+
+ begin
+ Decl :=
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Temp,
+ Object_Definition =>
+ New_Occurrence_Of (Formal_Typ, Loc));
+ Set_Etype (Temp, Formal_Typ);
+
+ Assn :=
+ Make_Assignment_Statement (Loc,
+ Name => New_Copy_Tree (Item),
+ Expression =>
+ Unchecked_Convert_To
+ (Etype (Item), New_Occurrence_Of (Temp, Loc)));
+
+ Rewrite (Item, New_Occurrence_Of (Temp, Loc));
+ Insert_Actions (N,
+ New_List (
+ Decl,
+ Make_Procedure_Call_Statement (Loc,
+ Name => New_Occurrence_Of (Pname, Loc),
+ Parameter_Associations => Exprs),
+ Assn));
+
+ Rewrite (N, Make_Null_Statement (Loc));
+ return;
+ end;
+ end if;
+
+ -- 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 (that is to say the stream
+ -- operation is not inherited), 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 not Is_Class_Wide_Type (Etype (Item))
+ 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;
+
+ -- The stream operation to call maybe a renaming created by
+ -- an attribute definition clause, and may not be frozen yet.
+ -- Ensure that it has the necessary extra formals.
+
+ if not Is_Frozen (Pname) then
+ Create_Extra_Formals (Pname);
+ 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 enabled. Do not apply check to
+ -- output parameters of an Asm instruction, since the value of this
+ -- is not set till after the attribute has been elaborated, and do
+ -- not apply the check to the arguments of a 'Read or 'Input attribute
+ -- reference since the scalar argument is an OUT scalar.
+
+ if Validity_Checks_On and then Validity_Check_Operands
+ and then Id /= Attribute_Asm_Output
+ and then Id /= Attribute_Read
+ and then Id /= Attribute_Input
+ then
+ declare
+ Expr : Node_Id;
+ begin
+ Expr := First (Expressions (N));
+ while Present (Expr) loop
+ Ensure_Valid (Expr);
+ Next (Expr);
+ end loop;
+ end;
+ end if;
+
+ -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
+ -- place function, then a temporary return object needs to be created
+ -- and access to it must be passed to the function. Currently we limit
+ -- such functions to those with inherently limited result subtypes, but
+ -- eventually we plan to expand the functions that are treated as
+ -- build-in-place to include other composite result types.
+
+ if Ada_Version >= Ada_2005
+ and then Is_Build_In_Place_Function_Call (Pref)
+ then
+ Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
+ end if;
+
+ -- If prefix is a protected type name, this is a reference to the
+ -- current instance of the type. For a component definition, nothing
+ -- to do (expansion will occur in the init proc). In other contexts,
+ -- rewrite into reference to current instance.
+
+ if Is_Protected_Self_Reference (Pref)
+ and then not
+ (Nkind_In (Parent (N), N_Index_Or_Discriminant_Constraint,
+ N_Discriminant_Association)
+ and then Nkind (Parent (Parent (Parent (Parent (N))))) =
+ N_Component_Definition)
+
+ -- No action needed for these attributes since the current instance
+ -- will be rewritten to be the name of the _object parameter
+ -- associated with the enclosing protected subprogram (see below).
+
+ and then Id /= Attribute_Access
+ and then Id /= Attribute_Unchecked_Access
+ and then Id /= Attribute_Unrestricted_Access
+ then
+ Rewrite (Pref, Concurrent_Ref (Pref));
+ Analyze (Pref);
+ end if;
+
+ -- Remaining processing depends on specific attribute
+
+ -- Note: individual sections of the following case statement are
+ -- allowed to assume there is no code after the case statement, and
+ -- are legitimately allowed to execute return statements if they have
+ -- nothing more to do.
+
+ case Id is
+
+ -- Attributes related to Ada 2012 iterators (placeholder ???)
+
+ when Attribute_Constant_Indexing |
+ Attribute_Default_Iterator |
+ Attribute_Implicit_Dereference |
+ Attribute_Iterator_Element |
+ Attribute_Variable_Indexing =>
+ null;
+
+ -- Internal attributes used to deal with Ada 2012 delayed aspects. These
+ -- were already rejected by the parser. Thus they shouldn't appear here.
+
+ when Internal_Attribute_Id =>
+ raise Program_Error;
+
+ ------------
+ -- Access --
+ ------------
+
+ when Attribute_Access |
+ Attribute_Unchecked_Access |
+ Attribute_Unrestricted_Access =>
+
+ Access_Cases : declare
+ Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
+ Btyp_DDT : Entity_Id;
+
+ function Enclosing_Object (N : Node_Id) return Node_Id;
+ -- If N denotes a compound name (selected component, indexed
+ -- component, or slice), returns the name of the outermost such
+ -- enclosing object. Otherwise returns N. If the object is a
+ -- renaming, then the renamed object is returned.
+
+ ----------------------
+ -- Enclosing_Object --
+ ----------------------
+
+ function Enclosing_Object (N : Node_Id) return Node_Id is
+ Obj_Name : Node_Id;
+
+ begin
+ Obj_Name := N;
+ while Nkind_In (Obj_Name, N_Selected_Component,
+ N_Indexed_Component,
+ N_Slice)
+ loop
+ Obj_Name := Prefix (Obj_Name);
+ end loop;
+
+ return Get_Referenced_Object (Obj_Name);
+ end Enclosing_Object;
+
+ -- Local declarations
+
+ Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
+
+ -- Start of processing for Access_Cases
+
+ begin
+ Btyp_DDT := Designated_Type (Btyp);
+
+ -- Handle designated types that come from the limited view
+
+ if Ekind (Btyp_DDT) = E_Incomplete_Type
+ and then From_With_Type (Btyp_DDT)
+ and then Present (Non_Limited_View (Btyp_DDT))
+ then
+ Btyp_DDT := Non_Limited_View (Btyp_DDT);
+
+ elsif Is_Class_Wide_Type (Btyp_DDT)
+ and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
+ and then From_With_Type (Etype (Btyp_DDT))
+ and then Present (Non_Limited_View (Etype (Btyp_DDT)))
+ and then Present (Class_Wide_Type
+ (Non_Limited_View (Etype (Btyp_DDT))))
+ then
+ Btyp_DDT :=
+ Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
+ end if;
+
+ -- In order to improve the text of error messages, the designated
+ -- type of access-to-subprogram itypes is set by the semantics as
+ -- the associated subprogram entity (see sem_attr). Now we replace
+ -- such node with the proper E_Subprogram_Type itype.
+
+ if Id = Attribute_Unrestricted_Access
+ and then Is_Subprogram (Directly_Designated_Type (Typ))
+ then
+ -- The following conditions ensure that this special management
+ -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
+ -- At this stage other cases in which the designated type is
+ -- still a subprogram (instead of an E_Subprogram_Type) are
+ -- wrong because the semantics must have overridden the type of
+ -- the node with the type imposed by the context.
+
+ if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
+ and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
+ then
+ Set_Etype (N, RTE (RE_Prim_Ptr));
+
+ else
+ declare
+ Subp : constant Entity_Id :=
+ Directly_Designated_Type (Typ);
+ Etyp : Entity_Id;
+ Extra : Entity_Id := Empty;
+ New_Formal : Entity_Id;
+ Old_Formal : Entity_Id := First_Formal (Subp);
+ Subp_Typ : Entity_Id;
+
+ begin
+ Subp_Typ := Create_Itype (E_Subprogram_Type, N);
+ Set_Etype (Subp_Typ, Etype (Subp));
+ Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
+
+ if Present (Old_Formal) then
+ New_Formal := New_Copy (Old_Formal);
+ Set_First_Entity (Subp_Typ, New_Formal);
+
+ loop
+ Set_Scope (New_Formal, Subp_Typ);
+ Etyp := Etype (New_Formal);
+
+ -- Handle itypes. There is no need to duplicate
+ -- here the itypes associated with record types
+ -- (i.e the implicit full view of private types).
+
+ if Is_Itype (Etyp)
+ and then Ekind (Base_Type (Etyp)) /= E_Record_Type
+ then
+ Extra := New_Copy (Etyp);
+ Set_Parent (Extra, New_Formal);
+ Set_Etype (New_Formal, Extra);
+ Set_Scope (Extra, Subp_Typ);
+ end if;
+
+ Extra := New_Formal;
+ Next_Formal (Old_Formal);
+ exit when No (Old_Formal);
+
+ Set_Next_Entity (New_Formal,
+ New_Copy (Old_Formal));
+ Next_Entity (New_Formal);
+ end loop;
+
+ Set_Next_Entity (New_Formal, Empty);
+ Set_Last_Entity (Subp_Typ, Extra);
+ end if;
+
+ -- Now that the explicit formals have been duplicated,
+ -- any extra formals needed by the subprogram must be
+ -- created.
+
+ if Present (Extra) then
+ Set_Extra_Formal (Extra, Empty);
+ end if;
+
+ Create_Extra_Formals (Subp_Typ);
+ Set_Directly_Designated_Type (Typ, Subp_Typ);
+ end;
+ end if;
+ end if;
+
+ if Is_Access_Protected_Subprogram_Type (Btyp) then
+ Expand_Access_To_Protected_Op (N, Pref, Typ);
+
+ -- If prefix is a type name, this is a reference to the current
+ -- instance of the type, within its initialization procedure.
+
+ elsif Is_Entity_Name (Pref)
+ and then Is_Type (Entity (Pref))
+ then
+ declare
+ Par : Node_Id;
+ Formal : Entity_Id;
+
+ begin
+ -- 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
+ -- 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);
+
+ elsif Is_Protected_Type (Entity (Pref)) then
+
+ -- No action needed for current instance located in a
+ -- component definition (expansion will occur in the
+ -- init proc)
+
+ if Is_Protected_Type (Current_Scope) then
+ null;
+
+ -- If the current instance reference is located in a
+ -- protected subprogram or entry then rewrite the access
+ -- attribute to be the name of the "_object" parameter.
+ -- An unchecked conversion is applied to ensure a type
+ -- match in cases of expander-generated calls (e.g. init
+ -- procs).
+
+ else
+ Formal :=
+ First_Entity
+ (Protected_Body_Subprogram (Current_Scope));
+ Rewrite (N,
+ Unchecked_Convert_To (Typ,
+ New_Occurrence_Of (Formal, Loc)));
+ Set_Etype (N, Typ);
+ end if;
+
+ -- The expression must appear in a default expression,
+ -- (which in the initialization procedure is the right-hand
+ -- side 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 the prefix of an Access attribute is a dereference of an
+ -- access parameter (or a renaming of such a dereference, or a
+ -- subcomponent of such a dereference) and the context is a
+ -- general access type (including the type of an object or
+ -- component with an access_definition, but not the anonymous
+ -- type of an access parameter or access discriminant), then
+ -- apply an accessibility check to the access parameter. We used
+ -- to rewrite the access parameter as a type conversion, but that
+ -- could only be done if the immediate prefix of the Access
+ -- attribute was the dereference, and didn't handle cases where
+ -- the attribute is applied to a subcomponent of the dereference,
+ -- since there's generally no available, appropriate access type
+ -- to convert to in that case. The attribute is passed as the
+ -- point to insert the check, because the access parameter may
+ -- come from a renaming, possibly in a different scope, and the
+ -- check must be associated with the attribute itself.
+
+ elsif Id = Attribute_Access
+ and then Nkind (Enc_Object) = N_Explicit_Dereference
+ and then Is_Entity_Name (Prefix (Enc_Object))
+ and then (Ekind (Btyp) = E_General_Access_Type
+ or else Is_Local_Anonymous_Access (Btyp))
+ and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
+ and then Ekind (Etype (Entity (Prefix (Enc_Object))))
+ = E_Anonymous_Access_Type
+ and then Present (Extra_Accessibility
+ (Entity (Prefix (Enc_Object))))
+ then
+ Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
+
+ -- Ada 2005 (AI-251): If the designated type is an interface we
+ -- add an implicit conversion to force the displacement of the
+ -- pointer to reference the secondary dispatch table.
+
+ elsif Is_Interface (Btyp_DDT)
+ and then (Comes_From_Source (N)
+ or else Comes_From_Source (Ref_Object)
+ or else (Nkind (Ref_Object) in N_Has_Chars
+ and then Chars (Ref_Object) = Name_uInit))
+ then
+ if Nkind (Ref_Object) /= N_Explicit_Dereference then
+
+ -- No implicit conversion required if types match, or if
+ -- the prefix is the class_wide_type of the interface. In
+ -- either case passing an object of the interface type has
+ -- already set the pointer correctly.
+
+ if Btyp_DDT = Etype (Ref_Object)
+ or else (Is_Class_Wide_Type (Etype (Ref_Object))
+ and then
+ Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
+ then
+ null;
+
+ else
+ Rewrite (Prefix (N),
+ Convert_To (Btyp_DDT,
+ New_Copy_Tree (Prefix (N))));
+
+ Analyze_And_Resolve (Prefix (N), Btyp_DDT);
+ end if;
+
+ -- When the object is an explicit dereference, convert the
+ -- dereference's prefix.
+
+ else
+ declare
+ Obj_DDT : constant Entity_Id :=
+ Base_Type
+ (Directly_Designated_Type
+ (Etype (Prefix (Ref_Object))));
+ begin
+ -- No implicit conversion required if designated types
+ -- match, or if we have an unrestricted access.
+
+ if Obj_DDT /= Btyp_DDT
+ and then Id /= Attribute_Unrestricted_Access
+ and then not (Is_Class_Wide_Type (Obj_DDT)
+ and then Etype (Obj_DDT) = Btyp_DDT)
+ then
+ Rewrite (N,
+ Convert_To (Typ,
+ New_Copy_Tree (Prefix (Ref_Object))));
+ Analyze_And_Resolve (N, Typ);
+ end if;
+ end;
+ end if;
+ end if;
+ end Access_Cases;
+
+ --------------
+ -- 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 (Ptyp));
+
+ while Present (Task_Proc) loop
+ exit when Ekind (Task_Proc) = E_Procedure
+ and then Etype (First_Formal (Task_Proc)) =
+ Corresponding_Record_Type (Ptyp);
+ 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 (Ptyp) = E_Subprogram_Type
+ and then Convention (Ptyp) = 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;
+
+ -- Ada 2005 (AI-251): Class-wide interface objects are always
+ -- "displaced" to reference the tag associated with the interface
+ -- type. In order to obtain the real address of such objects we
+ -- generate a call to a run-time subprogram that returns the base
+ -- address of the object.
+
+ -- This processing is not needed in the VM case, where dispatching
+ -- issues are taken care of by the virtual machine.
+
+ elsif Is_Class_Wide_Type (Ptyp)
+ and then Is_Interface (Ptyp)
+ and then Tagged_Type_Expansion
+ and then not (Nkind (Pref) in N_Has_Entity
+ and then Is_Subprogram (Entity (Pref)))
+ then
+ Rewrite (N,
+ Make_Function_Call (Loc,
+ Name => New_Reference_To (RTE (RE_Base_Address), Loc),
+ Parameter_Associations => New_List (
+ Relocate_Node (N))));
+ Analyze (N);
+ return;
+ end if;
+
+ -- Deal with packed array reference, other cases are handled by
+ -- the back end.
+
+ if Involves_Packed_Array_Reference (Pref) then
+ Expand_Packed_Address_Reference (N);
+ end if;
+ end Address;
+
+ ---------------
+ -- Alignment --
+ ---------------
+
+ when Attribute_Alignment => Alignment : declare
+ New_Node : Node_Id;
+
+ begin
+ -- For class-wide types, X'Class'Alignment is transformed into a
+ -- direct reference to the Alignment of the class type, so that the
+ -- back end does not have to deal with the X'Class'Alignment
+ -- reference.
+
+ if Is_Entity_Name (Pref)
+ and then Is_Class_Wide_Type (Entity (Pref))
+ then
+ Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
+ return;
+
+ -- For x'Alignment applied to an object of a class wide type,
+ -- transform X'Alignment into a call to the predefined primitive
+ -- operation _Alignment applied to X.
+
+ elsif Is_Class_Wide_Type (Ptyp) then
+ New_Node :=
+ Make_Attribute_Reference (Loc,
+ Prefix => Pref,
+ Attribute_Name => Name_Tag);
+
+ if VM_Target = No_VM then
+ New_Node := Build_Get_Alignment (Loc, New_Node);
+ else
+ New_Node :=
+ Make_Function_Call (Loc,
+ Name => New_Reference_To (RTE (RE_Get_Alignment), Loc),
+ Parameter_Associations => New_List (New_Node));
+ end if;
+
+ -- Case where 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.
+
+ if Typ /= Standard_Integer then
+ New_Node := Convert_To (Typ, New_Node);
+ end if;
+
+ Rewrite (N, New_Node);
+ Analyze_And_Resolve (N, Typ);
+ return;
+
+ -- For all other cases, we just have to deal with the case of
+ -- the fact that the result can be universal.
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+ end Alignment;
+
+ ---------------
+ -- 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 --
+ ---------
+
+ -- We compute this if a packed array reference was present, otherwise we
+ -- leave the computation up to the back end.
+
+ when Attribute_Bit =>
+ if Involves_Packed_Array_Reference (Pref) then
+ Expand_Packed_Bit_Reference (N);
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+
+ ------------------
+ -- Bit_Position --
+ ------------------
+
+ -- We compute this if a component clause was present, otherwise we leave
+ -- the computation up to the back end, 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
+ -- 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_Temporary (Loc, 'V');
+ Pent : Entity_Id;
+ S : String_Id;
+
+ begin
+ -- If not library unit, get to containing library unit
+
+ Pent := Entity (Pref);
+ while Pent /= Standard_Standard
+ and then Scope (Pent) /= Standard_Standard
+ and then not Is_Child_Unit (Pent)
+ loop
+ Pent := Scope (Pent);
+ end loop;
+
+ -- Special case Standard and Standard.ASCII
+
+ if Pent = Standard_Standard or else Pent = Standard_ASCII then
+ Rewrite (N,
+ Make_String_Literal (Loc,
+ Strval => Verbose_Library_Version));
+
+ -- 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));
+
+ -- Set entity as internal to ensure proper Sprint output of its
+ -- implicit importation.
+
+ Set_Is_Internal (E);
+
+ -- 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
+ -- We have an object of a task interface class-wide type as a prefix
+ -- to Callable. Generate:
+ -- callable (Task_Id (Pref._disp_get_task_id));
+
+ if Ada_Version >= Ada_2005
+ and then Ekind (Ptyp) = E_Class_Wide_Type
+ and then Is_Interface (Ptyp)
+ and then Is_Task_Interface (Ptyp)
+ then
+ Rewrite (N,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (RTE (RE_Callable), Loc),
+ Parameter_Associations => New_List (
+ Make_Unchecked_Type_Conversion (Loc,
+ Subtype_Mark =>
+ New_Reference_To (RTE (RO_ST_Task_Id), Loc),
+ Expression =>
+ Make_Selected_Component (Loc,
+ Prefix =>
+ New_Copy_Tree (Pref),
+ Selector_Name =>
+ Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
+
+ else
+ Rewrite (N,
+ Build_Call_With_Task (Pref, RTE (RE_Callable)));
+ end if;
+
+ 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 : constant Entity_Id := RTE (RO_AT_Task_Id);
+ Ent : constant Entity_Id := Entity (Pref);
+ Conctype : constant Entity_Id := Scope (Ent);
+ Nest_Depth : Integer := 0;
+ Name : Node_Id;
+ S : Entity_Id;
+
+ begin
+ -- Protected case
+
+ if Is_Protected_Type (Conctype) then
+ case Corresponding_Runtime_Package (Conctype) is
+ when System_Tasking_Protected_Objects_Entries =>
+ Name :=
+ New_Reference_To
+ (RTE (RE_Protected_Entry_Caller), Loc);
+
+ when System_Tasking_Protected_Objects_Single_Entry =>
+ Name :=
+ New_Reference_To
+ (RTE (RE_Protected_Single_Entry_Caller), Loc);
+
+ when others =>
+ raise Program_Error;
+ end case;
+
+ Rewrite (N,
+ Unchecked_Convert_To (Id_Kind,
+ Make_Function_Call (Loc,
+ Name => Name,
+ Parameter_Associations => New_List (
+ New_Reference_To
+ (Find_Protection_Object (Current_Scope), 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);
+
+ function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
+ -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
+ -- view of an aliased object whose subtype is constrained.
+
+ ---------------------------------
+ -- Is_Constrained_Aliased_View --
+ ---------------------------------
+
+ function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
+ E : Entity_Id;
+
+ begin
+ if Is_Entity_Name (Obj) then
+ E := Entity (Obj);
+
+ if Present (Renamed_Object (E)) then
+ return Is_Constrained_Aliased_View (Renamed_Object (E));
+ else
+ return Is_Aliased (E) and then Is_Constrained (Etype (E));
+ end if;
+
+ else
+ return Is_Aliased_View (Obj)
+ and then
+ (Is_Constrained (Etype (Obj))
+ or else
+ (Nkind (Obj) = N_Explicit_Dereference
+ and then
+ not Effectively_Has_Constrained_Partial_View
+ (Typ => Base_Type (Etype (Obj)),
+ Scop => Current_Scope)));
+ end if;
+ end Is_Constrained_Aliased_View;
+
+ -- Start of processing for Constrained
+
+ 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 this
+ -- is an entry in-parameter, it is replaced by a constant renaming
+ -- for which Extra_Constrained is never created.
+
+ if Present (Formal_Ent)
+ and then Ekind (Formal_Ent) /= E_Constant
+ 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
+ if Is_Composite_Type (Underlying_Type (Ent)) then
+ Res := Is_Constrained (Ent);
+ else
+ Res := True;
+ end if;
+ 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.
+
+ -- Ada 2005 (AI-363): An aliased prefix must be known to be
+ -- constrained in order to set the attribute to True.
+
+ elsif not Is_Variable (Pref)
+ or else Present (Formal_Ent)
+ or else (Ada_Version < Ada_2005
+ and then Is_Aliased_View (Pref))
+ or else (Ada_Version >= Ada_2005
+ and then Is_Constrained_Aliased_View (Pref))
+ then
+ Res := True;
+
+ -- Variable case, 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.
+
+ -- We use the Underlying_Type here (and below) in case the
+ -- type is private without discriminants, but the full type
+ -- has discriminants. This case is illegal, but we generate it
+ -- internally for passing to the Extra_Constrained parameter.
+
+ else
+ -- In Ada 2012, test for case of a limited tagged type, in
+ -- which case the attribute is always required to return
+ -- True. The underlying type is tested, to make sure we also
+ -- return True for cases where there is an unconstrained
+ -- object with an untagged limited partial view which has
+ -- defaulted discriminants (such objects always produce a
+ -- False in earlier versions of Ada). (Ada 2012: AI05-0214)
+
+ Res := Is_Constrained (Underlying_Type (Etype (Ent)))
+ or else
+ (Ada_Version >= Ada_2012
+ and then Is_Tagged_Type (Underlying_Type (Ptyp))
+ and then Is_Limited_Type (Ptyp));
+ end if;
+
+ Rewrite (N, New_Reference_To (Boolean_Literals (Res), Loc));
+ 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. If an explicit dereference of an object with constrained
+ -- partial view, this is unconstrained (Ada 2005: AI95-0363). If the
+ -- underlying type is a limited tagged type, then Constrained is
+ -- required to always return True (Ada 2012: AI05-0214).
+
+ else
+ Rewrite (N,
+ New_Reference_To (
+ Boolean_Literals (
+ not Is_Variable (Pref)
+ or else
+ (Nkind (Pref) = N_Explicit_Dereference
+ and then
+ not Effectively_Has_Constrained_Partial_View
+ (Typ => Base_Type (Ptyp),
+ Scop => Current_Scope))
+ or else Is_Constrained (Underlying_Type (Ptyp))
+ or else (Ada_Version >= Ada_2012
+ and then Is_Tagged_Type (Underlying_Type (Ptyp))
+ and then Is_Limited_Type (Ptyp))),
+ Loc));
+ 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
+ Call : Node_Id;
+ Conctyp : Entity_Id;
+ Entnam : Node_Id;
+ Entry_Id : Entity_Id;
+ Index : Node_Id;
+ Name : Node_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;
+
+ Entry_Id := Entity (Entnam);
+
+ -- 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
+ case Corresponding_Runtime_Package (Conctyp) is
+ when System_Tasking_Protected_Objects_Entries =>
+ Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
+
+ Call :=
+ Make_Function_Call (Loc,
+ Name => Name,
+ Parameter_Associations => New_List (
+ New_Reference_To
+ (Find_Protection_Object (Current_Scope), Loc),
+ Entry_Index_Expression
+ (Loc, Entry_Id, Index, Scope (Entry_Id))));
+
+ when System_Tasking_Protected_Objects_Single_Entry =>
+ Name :=
+ New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
+
+ Call :=
+ Make_Function_Call (Loc,
+ Name => Name,
+ Parameter_Associations => New_List (
+ New_Reference_To
+ (Find_Protection_Object (Current_Scope), Loc)));
+
+ when others =>
+ raise Program_Error;
+ end case;
+
+ -- 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,
+ Entry_Id, Index, Scope (Entry_Id))));
+ 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;
+
+ ---------------------
+ -- Descriptor_Size --
+ ---------------------
+
+ when Attribute_Descriptor_Size =>
+
+ -- Attribute Descriptor_Size is handled by the back end when applied
+ -- to an unconstrained array type.
+
+ if Is_Array_Type (Ptyp)
+ and then not Is_Constrained (Ptyp)
+ then
+ Apply_Universal_Integer_Attribute_Checks (N);
+
+ -- For any other type, the descriptor size is 0 because there is no
+ -- actual descriptor, but the result is not formally static.
+
+ else
+ Rewrite (N, Make_Integer_Literal (Loc, 0));
+ Analyze (N);
+ Set_Is_Static_Expression (N, False);
+ end if;
+
+ ---------------
+ -- 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 =>
+
+ -- Leave attribute unexpanded in CodePeer mode: the gnat2scil
+ -- back-end knows how to handle these attributes directly.
+
+ if CodePeer_Mode then
+ return;
+ end if;
+
+ Elab_Body : declare
+ Ent : constant Entity_Id := Make_Temporary (Loc, '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.
+
+ ----------------------
+ -- Make_Elab_String --
+ ----------------------
+
+ procedure Make_Elab_String (Nod : Node_Id) is
+ begin
+ if Nkind (Nod) = N_Selected_Component then
+ Make_Elab_String (Prefix (Nod));
+
+ case VM_Target is
+ when JVM_Target =>
+ Store_String_Char ('$');
+ when CLI_Target =>
+ Store_String_Char ('.');
+ when No_VM =>
+ Store_String_Char ('_');
+ Store_String_Char ('_');
+ end case;
+
+ 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 VM_Target = No_VM then
+ Store_String_Chars ("___elab");
+ Lang := Make_Identifier (Loc, Name_C);
+ else
+ Store_String_Chars ("._elab");
+ Lang := Make_Identifier (Loc, Name_Ada);
+ 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;
+
+ --------------------
+ -- Elab_Subp_Body --
+ --------------------
+
+ -- Always ignored. In CodePeer mode, gnat2scil knows how to handle
+ -- this attribute directly, and if we are not in CodePeer mode it is
+ -- entirely ignored ???
+
+ when Attribute_Elab_Subp_Body =>
+ return;
+
+ ----------------
+ -- 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 to the back end
+
+ when Attribute_Elaborated => Elaborated : declare
+ Ent : constant Entity_Id := Entity (Pref);
+
+ begin
+ if Present (Elaboration_Entity (Ent)) then
+ Rewrite (N,
+ Make_Op_Ne (Loc,
+ Left_Opnd =>
+ New_Occurrence_Of (Elaboration_Entity (Ent), Loc),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc, Uint_0)));
+ Analyze_And_Resolve (N, Typ);
+ 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 the back end 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))));
+
+ -- If this is a renaming of a literal, recover the representation
+ -- of the original.
+
+ elsif Ekind (Entity (Pref)) = E_Constant
+ and then Present (Renamed_Object (Entity (Pref)))
+ and then
+ Ekind (Entity (Renamed_Object (Entity (Pref))))
+ = E_Enumeration_Literal
+ then
+ Rewrite (N,
+ Make_Integer_Literal (Loc,
+ Enumeration_Rep (Entity (Renamed_Object (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;
+
+ --------------
+ -- Enum_Val --
+ --------------
+
+ when Attribute_Enum_Val => Enum_Val : declare
+ Expr : Node_Id;
+ Btyp : constant Entity_Id := Base_Type (Ptyp);
+
+ begin
+ -- X'Enum_Val (Y) expands to
+
+ -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
+ -- X!(Y);
+
+ Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
+
+ Insert_Action (N,
+ Make_Raise_Constraint_Error (Loc,
+ Condition =>
+ Make_Op_Eq (Loc,
+ Left_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
+ Parameter_Associations => New_List (
+ Relocate_Node (Duplicate_Subexpr (Expr)),
+ New_Occurrence_Of (Standard_False, Loc))),
+
+ Right_Opnd => Make_Integer_Literal (Loc, -1)),
+ Reason => CE_Range_Check_Failed));
+
+ Rewrite (N, Expr);
+ Analyze_And_Resolve (N, Ptyp);
+ end Enum_Val;
+
+ --------------
+ -- 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 =>
+
+ -- 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 the back end 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;
+
+ ---------------
+ -- First_Bit --
+ ---------------
+
+ -- Compute this if component clause was present, otherwise we leave the
+ -- computation to be completed in the back-end, since we don't know what
+ -- layout will be chosen.
+
+ when Attribute_First_Bit => First_Bit_Attr : declare
+ CE : constant Entity_Id := Entity (Selector_Name (Pref));
+
+ begin
+ -- In Ada 2005 (or later) if we have the standard nondefault
+ -- bit order, then we return the original value as given in
+ -- the component clause (RM 2005 13.5.2(3/2)).
+
+ if Present (Component_Clause (CE))
+ and then Ada_Version >= Ada_2005
+ and then not Reverse_Bit_Order (Scope (CE))
+ then
+ Rewrite (N,
+ Make_Integer_Literal (Loc,
+ Intval => Expr_Value (First_Bit (Component_Clause (CE)))));
+ Analyze_And_Resolve (N, Typ);
+
+ -- Otherwise (Ada 83/95 or Ada 2005 or later with reverse bit order),
+ -- rewrite with normalized value if we know it statically.
+
+ elsif 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);
+
+ -- Otherwise left to back end, just do universal integer checks
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+ end First_Bit_Attr;
+
+ -----------------
+ -- 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 the back end 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);
+
+ -- Note: it might appear that a properly analyzed unchecked conversion
+ -- would be just fine here, but that's not the case, since the full
+ -- range checks performed by the following call are critical!
+
+ 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 (Universal_Real (Type'First)),
+ -- Universal_Real (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 : begin
+ Rewrite (N,
+ Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name => New_Reference_To (RTE (RE_Fore), Loc),
+
+ Parameter_Associations => New_List (
+ Convert_To (Universal_Real,
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Reference_To (Ptyp, Loc),
+ Attribute_Name => Name_First)),
+
+ Convert_To (Universal_Real,
+ 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);
+
+ --------------
+ -- From_Any --
+ --------------
+
+ when Attribute_From_Any => From_Any : declare
+ P_Type : constant Entity_Id := Etype (Pref);
+ Decls : constant List_Id := New_List;
+ begin
+ Rewrite (N,
+ Build_From_Any_Call (P_Type,
+ Relocate_Node (First (Exprs)),
+ Decls));
+ Insert_Actions (N, Decls);
+ Analyze_And_Resolve (N, P_Type);
+ end From_Any;
+
+ --------------
+ -- 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 Ptyp = 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);
+
+ -- If the prefix is a task interface, the Task_Id is obtained
+ -- dynamically through a dispatching call, as for other task
+ -- attributes applied to interfaces.
+
+ if Ada_Version >= Ada_2005
+ and then Ekind (Ptyp) = E_Class_Wide_Type
+ and then Is_Interface (Ptyp)
+ and then Is_Task_Interface (Ptyp)
+ then
+ Rewrite (N,
+ Unchecked_Convert_To (Id_Kind,
+ Make_Selected_Component (Loc,
+ Prefix =>
+ New_Copy_Tree (Pref),
+ Selector_Name =>
+ Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
+
+ else
+ Rewrite (N,
+ Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
+ end if;
+ 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 (Ptyp, 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.
+
+ procedure Freeze_Stream_Subprogram (F : Entity_Id);
+ -- The expansion of the attribute reference may generate a call to
+ -- a user-defined stream subprogram that is frozen by the call. This
+ -- can lead to access-before-elaboration problem if the reference
+ -- appears in an object declaration and the subprogram body has not
+ -- been seen. The freezing of the subprogram requires special code
+ -- because it appears in an expanded context where expressions do
+ -- not freeze their constituents.
+
+ ------------------------------
+ -- Freeze_Stream_Subprogram --
+ ------------------------------
+
+ procedure Freeze_Stream_Subprogram (F : Entity_Id) is
+ Decl : constant Node_Id := Unit_Declaration_Node (F);
+ Bod : Node_Id;
+
+ begin
+ -- If this is user-defined subprogram, the corresponding
+ -- stream function appears as a renaming-as-body, and the
+ -- user subprogram must be retrieved by tree traversal.
+
+ if Present (Decl)
+ and then Nkind (Decl) = N_Subprogram_Declaration
+ and then Present (Corresponding_Body (Decl))
+ then
+ Bod := Corresponding_Body (Decl);
+
+ if Nkind (Unit_Declaration_Node (Bod)) =
+ N_Subprogram_Renaming_Declaration
+ then
+ Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
+ end if;
+ end if;
+ end Freeze_Stream_Subprogram;
+
+ -- Start of processing for Input
+
+ 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_Stream_Subprogram (P_Type, TSS_Stream_Input);
+
+ 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 streamread is the given Read function that converts an
+ -- argument of type strmtyp to type sourcetyp or a type from which
+ -- it is derived (extra conversion required for the derived case).
+
+ Prag := Get_Stream_Convert_Pragma (P_Type);
+
+ 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 (Base_Type (U_Type), TSS_Stream_Read)) 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
+
+ -- No need to do anything else compiling under restriction
+ -- No_Dispatching_Calls. During the semantic analysis we
+ -- already notified such violation.
+
+ if Restriction_Active (No_Dispatching_Calls) then
+ return;
+ end if;
+
+ declare
+ Rtyp : constant Entity_Id := Root_Type (P_Type);
+ Dnn : Entity_Id;
+ Decl : Node_Id;
+ Expr : 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 :=
+ -- Descendant_Tag (String'Input (Strm), P_Type);
+
+ -- This dummy object is used only to provide a controlling
+ -- argument for the eventual _Input call. Descendant_Tag is
+ -- called rather than Internal_Tag to ensure that we have a
+ -- tag for a type that is descended from the prefix type and
+ -- declared at the same accessibility level (the exception
+ -- Tag_Error will be raised otherwise). The level check is
+ -- required for Ada 2005 because tagged types can be
+ -- extended in nested scopes (AI-344).
+
+ Expr :=
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of (RTE (RE_Descendant_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)))),
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Reference_To (P_Type, Loc),
+ Attribute_Name => Name_Tag)));
+
+ Dnn := Make_Temporary (Loc, 'D', Expr);
+
+ Decl :=
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Dnn,
+ Object_Definition =>
+ New_Occurrence_Of (RTE (RE_Tag), Loc),
+ Expression => Expr);
+
+ 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 convert
+ -- to the class-wide tagged type to make it look like a real
+ -- tagged object).
+
+ Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
+ Cntrl :=
+ Unchecked_Convert_To (P_Type,
+ New_Occurrence_Of (Dnn, Loc));
+ Set_Etype (Cntrl, P_Type);
+ 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, TSS_Stream_Input);
+
+ -- 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));
+
+ -- Ada 2005 (AI-216): Program_Error is raised executing default
+ -- implementation of the Input attribute of an unchecked union
+ -- type if the type lacks default discriminant values.
+
+ if Is_Unchecked_Union (Base_Type (U_Type))
+ and then No (Discriminant_Constraint (U_Type))
+ then
+ Insert_Action (N,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Unchecked_Union_Restriction));
+
+ return;
+ end if;
+
+ -- Build the type's Input function, passing the subtype rather
+ -- than its base type, because checks are needed in the case of
+ -- constrained discriminants (see Ada 2012 AI05-0192).
+
+ Build_Record_Or_Elementary_Input_Function
+ (Loc, U_Type, Decl, Fname);
+ Insert_Action (N, Decl);
+
+ if Nkind (Parent (N)) = N_Object_Declaration
+ and then Is_Record_Type (U_Type)
+ then
+ -- The stream function may contain calls to user-defined
+ -- Read procedures for individual components.
+
+ declare
+ Comp : Entity_Id;
+ Func : Entity_Id;
+
+ begin
+ Comp := First_Component (U_Type);
+ while Present (Comp) loop
+ Func :=
+ Find_Stream_Subprogram
+ (Etype (Comp), TSS_Stream_Read);
+
+ if Present (Func) then
+ Freeze_Stream_Subprogram (Func);
+ end if;
+
+ Next_Component (Comp);
+ end loop;
+ end;
+ end if;
+ 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);
+
+ if Nkind (Parent (N)) = N_Object_Declaration then
+ Freeze_Stream_Subprogram (Fname);
+ end if;
+ 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 the back end 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);
+
+ -- Note: it might appear that a properly analyzed unchecked conversion
+ -- would be just fine here, but that's not the case, since the full
+ -- range checks performed by the following call are critical!
+
+ Apply_Type_Conversion_Checks (N);
+ end Integer_Value;
+
+ -------------------
+ -- Invalid_Value --
+ -------------------
+
+ when Attribute_Invalid_Value =>
+ Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
+
+ ----------
+ -- Last --
+ ----------
+
+ when Attribute_Last =>
+
+ -- 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 the back end 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;
+
+ --------------
+ -- Last_Bit --
+ --------------
+
+ -- We compute this if a component clause was present, otherwise we leave
+ -- the computation up to the back end, since we don't know what layout
+ -- will be chosen.
+
+ when Attribute_Last_Bit => Last_Bit_Attr : declare
+ CE : constant Entity_Id := Entity (Selector_Name (Pref));
+
+ begin
+ -- In Ada 2005 (or later) if we have the standard nondefault
+ -- bit order, then we return the original value as given in
+ -- the component clause (RM 2005 13.5.2(4/2)).
+
+ if Present (Component_Clause (CE))
+ and then Ada_Version >= Ada_2005
+ and then not Reverse_Bit_Order (Scope (CE))
+ then
+ Rewrite (N,
+ Make_Integer_Literal (Loc,
+ Intval => Expr_Value (Last_Bit (Component_Clause (CE)))));
+ Analyze_And_Resolve (N, Typ);
+
+ -- Otherwise (Ada 83/95 or Ada 2005 or later with reverse bit order),
+ -- rewrite with normalized value if we know it statically.
+
+ elsif 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);
+
+ -- Otherwise leave to back end, just apply universal integer checks
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+ end Last_Bit_Attr;
+
+ ------------------
+ -- 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 generate 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 => Length : declare
+ 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 the back end 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_No_Checks (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 the back end
+ -- 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;
+
+ -- 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_No_Checks (Pref),
+ Attribute_Name => Name_First,
+ Expressions =>
+ New_Copy_List (Exprs)))))))));
+
+ Analyze_And_Resolve (N, Typ);
+ end if;
+ end;
+
+ -- Otherwise leave it to the back end
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+ end Length;
+
+ -- The expansion of this attribute is carried out when the target loop
+ -- is processed. See Expand_Loop_Entry_Attributes for details.
+
+ when Attribute_Loop_Entry =>
+ null;
+
+ -------------
+ -- 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_Rounding --
+ ----------------------
+
+ -- Transforms 'Machine_Rounding into a call to the floating-point
+ -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
+ -- type). Expansion is avoided for cases the back end can handle
+ -- directly.
+
+ when Attribute_Machine_Rounding =>
+ if not Is_Inline_Floating_Point_Attribute (N) then
+ Expand_Fpt_Attribute_R (N);
+ end if;
+
+ ------------------
+ -- Machine_Size --
+ ------------------
+
+ -- Machine_Size is equivalent to Object_Size, so transform it into
+ -- Object_Size and that way the back end 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 : 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;
+
+ ----------------------------------
+ -- Max_Size_In_Storage_Elements --
+ ----------------------------------
+
+ when Attribute_Max_Size_In_Storage_Elements => declare
+ Typ : constant Entity_Id := Etype (N);
+ Attr : Node_Id;
+
+ Conversion_Added : Boolean := False;
+ -- A flag which tracks whether the original attribute has been
+ -- wrapped inside a type conversion.
+
+ begin
+ Apply_Universal_Integer_Attribute_Checks (N);
+
+ -- The universal integer check may sometimes add a type conversion,
+ -- retrieve the original attribute reference from the expression.
+
+ Attr := N;
+ if Nkind (Attr) = N_Type_Conversion then
+ Attr := Expression (Attr);
+ Conversion_Added := True;
+ end if;
+
+ -- Heap-allocated controlled objects contain two extra pointers which
+ -- are not part of the actual type. Transform the attribute reference
+ -- into a runtime expression to add the size of the hidden header.
+
+ -- Do not perform this expansion on .NET/JVM targets because the
+ -- two pointers are already present in the type.
+
+ if VM_Target = No_VM
+ and then Nkind (Attr) = N_Attribute_Reference
+ and then Needs_Finalization (Ptyp)
+ and then not Header_Size_Added (Attr)
+ then
+ Set_Header_Size_Added (Attr);
+
+ -- Generate:
+ -- P'Max_Size_In_Storage_Elements +
+ -- Universal_Integer
+ -- (Header_Size_With_Padding (Ptyp'Alignment))
+
+ Rewrite (Attr,
+ Make_Op_Add (Loc,
+ Left_Opnd => Relocate_Node (Attr),
+ Right_Opnd =>
+ Convert_To (Universal_Integer,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (RTE (RE_Header_Size_With_Padding), Loc),
+
+ Parameter_Associations => New_List (
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Reference_To (Ptyp, Loc),
+ Attribute_Name => Name_Alignment))))));
+
+ -- Add a conversion to the target type
+
+ if not Conversion_Added then
+ Rewrite (Attr,
+ Make_Type_Conversion (Loc,
+ Subtype_Mark => New_Reference_To (Typ, Loc),
+ Expression => Relocate_Node (Attr)));
+ end if;
+
+ Analyze (Attr);
+ return;
+ end if;
+ end;
+
+ --------------------
+ -- Mechanism_Code --
+ --------------------
+
+ when Attribute_Mechanism_Code =>
+
+ -- We must replace the prefix in the renamed case
+
+ if Is_Entity_Name (Pref)
+ and then Present (Alias (Entity (Pref)))
+ then
+ Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
+ end if;
+
+ ---------
+ -- Mod --
+ ---------
+
+ when Attribute_Mod => Mod_Case : declare
+ Arg : constant Node_Id := Relocate_Node (First (Exprs));
+ Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
+ Modv : constant Uint := Modulus (Btyp);
+
+ begin
+
+ -- This is not so simple. The issue is what type to use for the
+ -- computation of the modular value.
+
+ -- The easy case is when the modulus value is within the bounds
+ -- of the signed integer type of the argument. In this case we can
+ -- just do the computation in that signed integer type, and then
+ -- do an ordinary conversion to the target type.
+
+ if Modv <= Expr_Value (Hi) then
+ Rewrite (N,
+ Convert_To (Btyp,
+ Make_Op_Mod (Loc,
+ Left_Opnd => Arg,
+ Right_Opnd => Make_Integer_Literal (Loc, Modv))));
+
+ -- Here we know that the modulus is larger than type'Last of the
+ -- integer type. There are two cases to consider:
+
+ -- a) The integer value is non-negative. In this case, it is
+ -- returned as the result (since it is less than the modulus).
+
+ -- b) The integer value is negative. In this case, we know that the
+ -- result is modulus + value, where the value might be as small as
+ -- -modulus. The trouble is what type do we use to do the subtract.
+ -- No type will do, since modulus can be as big as 2**64, and no
+ -- integer type accommodates this value. Let's do bit of algebra
+
+ -- modulus + value
+ -- = modulus - (-value)
+ -- = (modulus - 1) - (-value - 1)
+
+ -- Now modulus - 1 is certainly in range of the modular type.
+ -- -value is in the range 1 .. modulus, so -value -1 is in the
+ -- range 0 .. modulus-1 which is in range of the modular type.
+ -- Furthermore, (-value - 1) can be expressed as -(value + 1)
+ -- which we can compute using the integer base type.
+
+ -- Once this is done we analyze the if expression without range
+ -- checks, because we know everything is in range, and we want
+ -- to prevent spurious warnings on either branch.
+
+ else
+ Rewrite (N,
+ Make_If_Expression (Loc,
+ Expressions => New_List (
+ Make_Op_Ge (Loc,
+ Left_Opnd => Duplicate_Subexpr (Arg),
+ Right_Opnd => Make_Integer_Literal (Loc, 0)),
+
+ Convert_To (Btyp,
+ Duplicate_Subexpr_No_Checks (Arg)),
+
+ Make_Op_Subtract (Loc,
+ Left_Opnd =>
+ Make_Integer_Literal (Loc,
+ Intval => Modv - 1),
+ Right_Opnd =>
+ Convert_To (Btyp,
+ Make_Op_Minus (Loc,
+ Right_Opnd =>
+ Make_Op_Add (Loc,
+ Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc,
+ Intval => 1))))))));
+
+ end if;
+
+ Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
+ end Mod_Case;
+
+ -----------
+ -- 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
+
+ ---------
+ -- Old --
+ ---------
+
+ when Attribute_Old => Old : declare
+ Tnn : constant Entity_Id := Make_Temporary (Loc, 'T', Pref);
+ Subp : Node_Id;
+ Asn_Stm : Node_Id;
+
+ begin
+ -- If assertions are disabled, no need to create the declaration
+ -- that preserves the value.
+
+ if not Assertions_Enabled then
+ return;
+ end if;
+
+ -- Find the nearest subprogram body, ignoring _Preconditions
+
+ Subp := N;
+ loop
+ Subp := Parent (Subp);
+ exit when Nkind (Subp) = N_Subprogram_Body
+ and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
+ end loop;
+
+ -- Insert the initialized object declaration at the start of the
+ -- subprogram's declarations.
+
+ Asn_Stm :=
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Tnn,
+ Constant_Present => True,
+ Object_Definition => New_Occurrence_Of (Etype (N), Loc),
+ Expression => Pref);
+
+ -- Push the subprogram's scope, so that the object will be analyzed
+ -- in that context (rather than the context of the Precondition
+ -- subprogram) and will have its Scope set properly.
+
+ if Present (Corresponding_Spec (Subp)) then
+ Push_Scope (Corresponding_Spec (Subp));
+ else
+ Push_Scope (Defining_Entity (Subp));
+ end if;
+
+ if Is_Empty_List (Declarations (Subp)) then
+ Set_Declarations (Subp, New_List (Asn_Stm));
+ Analyze (Asn_Stm);
+ else
+ Insert_Action (First (Declarations (Subp)), Asn_Stm);
+ end if;
+
+ Pop_Scope;
+
+ Rewrite (N, New_Occurrence_Of (Tnn, Loc));
+ end Old;
+
+ ----------------------
+ -- Overlaps_Storage --
+ ----------------------
+
+ when Attribute_Overlaps_Storage => Overlaps_Storage : declare
+ Loc : constant Source_Ptr := Sloc (N);
+
+ X : constant Node_Id := Prefix (N);
+ Y : constant Node_Id := First (Expressions (N));
+ -- The argumens
+
+ X_Addr, Y_Addr : Node_Id;
+ -- the expressions for their integer addresses
+
+ X_Size, Y_Size : Node_Id;
+ -- the expressions for their sizes
+
+ Cond : Node_Id;
+
+ begin
+ -- Attribute expands into:
+
+ -- if X'Address < Y'address then
+ -- (X'address + X'Size - 1) >= Y'address
+ -- else
+ -- (Y'address + Y'size - 1) >= X'Address
+ -- end if;
+
+ -- with the proper address operations. We convert addresses to
+ -- integer addresses to use predefined arithmetic. The size is
+ -- expressed in storage units.
+
+ X_Addr :=
+ Unchecked_Convert_To (RTE (RE_Integer_Address),
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Address,
+ Prefix => New_Copy_Tree (X)));
+
+ Y_Addr :=
+ Unchecked_Convert_To (RTE (RE_Integer_Address),
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Address,
+ Prefix => New_Copy_Tree (Y)));
+
+ X_Size :=
+ Make_Op_Divide (Loc,
+ Left_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Size,
+ Prefix => New_Copy_Tree (X)),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc, System_Storage_Unit));
+
+ Y_Size :=
+ Make_Op_Divide (Loc,
+ Left_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Size,
+ Prefix => New_Copy_Tree (Y)),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc, System_Storage_Unit));
+
+ Cond :=
+ Make_Op_Le (Loc,
+ Left_Opnd => X_Addr,
+ Right_Opnd => Y_Addr);
+
+ Rewrite (N,
+ Make_If_Expression (Loc,
+ New_List (
+ Cond,
+
+ Make_Op_Ge (Loc,
+ Left_Opnd =>
+ Make_Op_Add (Loc,
+ Left_Opnd => X_Addr,
+ Right_Opnd =>
+ Make_Op_Subtract (Loc,
+ Left_Opnd => X_Size,
+ Right_Opnd => Make_Integer_Literal (Loc, 1))),
+ Right_Opnd => Y_Addr),
+
+ Make_Op_Ge (Loc,
+ Make_Op_Add (Loc,
+ Left_Opnd => Y_Addr,
+ Right_Opnd =>
+ Make_Op_Subtract (Loc,
+ Left_Opnd => Y_Size,
+ Right_Opnd => Make_Integer_Literal (Loc, 1))),
+ Right_Opnd => X_Addr))));
+
+ Analyze_And_Resolve (N, Standard_Boolean);
+ end Overlaps_Storage;
+
+ ------------
+ -- Output --
+ ------------
+
+ when Attribute_Output => Output : 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;
+
+ -- If TSS for Output is present, just call it
+
+ Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
+
+ 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_Stream_Convert_Pragma (P_Type);
+
+ 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 (
+ OK_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 (Base_Type (U_Type), TSS_Stream_Write)) 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
+
+ -- No need to do anything else compiling under restriction
+ -- No_Dispatching_Calls. During the semantic analysis we
+ -- already notified such violation.
+
+ if Restriction_Active (No_Dispatching_Calls) then
+ return;
+ end if;
+
+ Tag_Write : declare
+ Strm : constant Node_Id := First (Exprs);
+ Item : constant Node_Id := Next (Strm);
+
+ begin
+ -- Ada 2005 (AI-344): Check that the accessibility level
+ -- of the type of the output object is not deeper than
+ -- that of the attribute's prefix type.
+
+ -- if Get_Access_Level (Item'Tag)
+ -- /= Get_Access_Level (P_Type'Tag)
+ -- then
+ -- raise Tag_Error;
+ -- end if;
+
+ -- String'Output (Strm, External_Tag (Item'Tag));
+
+ -- We cannot figure out a practical way to implement this
+ -- accessibility check on virtual machines, so we omit it.
+
+ if Ada_Version >= Ada_2005
+ and then Tagged_Type_Expansion
+ then
+ Insert_Action (N,
+ Make_Implicit_If_Statement (N,
+ Condition =>
+ Make_Op_Ne (Loc,
+ Left_Opnd =>
+ Build_Get_Access_Level (Loc,
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ Relocate_Node (
+ Duplicate_Subexpr (Item,
+ Name_Req => True)),
+ Attribute_Name => Name_Tag)),
+
+ Right_Opnd =>
+ Make_Integer_Literal (Loc,
+ Type_Access_Level (P_Type))),
+
+ Then_Statements =>
+ New_List (Make_Raise_Statement (Loc,
+ New_Occurrence_Of (
+ RTE (RE_Tag_Error), Loc)))));
+ end if;
+
+ 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, TSS_Stream_Output);
+
+ -- Tagged type case, use the primitive Output function
+
+ elsif Is_Tagged_Type (U_Type) then
+ Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
+
+ -- 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));
+
+ -- Ada 2005 (AI-216): Program_Error is raised when executing
+ -- the default implementation of the Output attribute of an
+ -- unchecked union type if the type lacks default discriminant
+ -- values.
+
+ if Is_Unchecked_Union (Base_Type (U_Type))
+ and then No (Discriminant_Constraint (U_Type))
+ then
+ Insert_Action (N,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Unchecked_Union_Restriction));
+
+ return;
+ end if;
+
+ 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 the back end.
+
+ -- 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, flag)
+
+ -- The parameter flag is True if range checks are enabled, causing
+ -- Program_Error to be raised if the expression has an invalid
+ -- representation, and False if range checks are suppressed.
+
+ -- 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, Rep_To_Pos_Flag (Etyp, Loc));
+ Rewrite (N,
+ Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (TSS (Etyp, TSS_Rep_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 the back end, since we don't know what layout
+ -- will be chosen.
+
+ when Attribute_Position => Position_Attr :
+ declare
+ CE : constant Entity_Id := Entity (Selector_Name (Pref));
+
+ begin
+ if Present (Component_Clause (CE)) then
+
+ -- In Ada 2005 (or later) if we have the standard nondefault
+ -- bit order, then we return the original value as given in
+ -- the component clause (RM 2005 13.5.2(2/2)).
+
+ if Ada_Version >= Ada_2005
+ and then not Reverse_Bit_Order (Scope (CE))
+ then
+ Rewrite (N,
+ Make_Integer_Literal (Loc,
+ Intval => Expr_Value (Position (Component_Clause (CE)))));
+
+ -- Otherwise (Ada 83 or 95, or reverse bit order specified in
+ -- later Ada version), return the normalized value.
+
+ else
+ Rewrite (N,
+ Make_Integer_Literal (Loc,
+ Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
+ end if;
+
+ Analyze_And_Resolve (N, Typ);
+
+ -- If back end is doing things, just apply universal integer checks
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+ end if;
+ end Position_Attr;
+
+ ----------
+ -- 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
+ Etyp : constant Entity_Id := Base_Type (Ptyp);
+
+ begin
+
+ -- For enumeration types with non-standard representations, we
+ -- expand typ'Pred (x) into
+
+ -- Pos_To_Rep (Rep_To_Pos (x) - 1)
+
+ -- If the representation is contiguous, we compute instead
+ -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
+ -- The conversion function Enum_Pos_To_Rep is defined on the
+ -- base type, not the subtype, so we have to use the base type
+ -- explicitly for this and other enumeration attributes.
+
+ if Is_Enumeration_Type (Ptyp)
+ and then Present (Enum_Pos_To_Rep (Etyp))
+ then
+ if Has_Contiguous_Rep (Etyp) then
+ Rewrite (N,
+ Unchecked_Convert_To (Ptyp,
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Make_Integer_Literal (Loc,
+ Enumeration_Rep (First_Literal (Ptyp))),
+ Right_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (TSS (Etyp, TSS_Rep_To_Pos), Loc),
+
+ Parameter_Associations =>
+ New_List (
+ Unchecked_Convert_To (Ptyp,
+ Make_Op_Subtract (Loc,
+ Left_Opnd =>
+ Unchecked_Convert_To (Standard_Integer,
+ Relocate_Node (First (Exprs))),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc, 1))),
+ Rep_To_Pos_Flag (Ptyp, Loc))))));
+
+ else
+ -- Add Boolean parameter True, to request program errror if
+ -- we have a bad representation on our hands. If checks are
+ -- suppressed, then add False instead
+
+ Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
+ Rewrite (N,
+ Make_Indexed_Component (Loc,
+ Prefix =>
+ New_Reference_To
+ (Enum_Pos_To_Rep (Etyp), Loc),
+ Expressions => New_List (
+ Make_Op_Subtract (Loc,
+ Left_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (TSS (Etyp, TSS_Rep_To_Pos), Loc),
+ Parameter_Associations => Exprs),
+ Right_Opnd => Make_Integer_Literal (Loc, 1)))));
+ end if;
+
+ 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 argument is marked as needing a range check or
+ -- overflow checking is enabled, we must generate a check.
+
+ elsif not Overflow_Checks_Suppressed (Ptyp)
+ or else Do_Range_Check (First (Exprs))
+ then
+ Set_Do_Range_Check (First (Exprs), False);
+ Expand_Pred_Succ (N);
+ end if;
+ end Pred;
+
+ --------------
+ -- Priority --
+ --------------
+
+ -- Ada 2005 (AI-327): Dynamic ceiling priorities
+
+ -- We rewrite X'Priority as the following run-time call:
+
+ -- Get_Ceiling (X._Object)
+
+ -- Note that although X'Priority is notionally an object, it is quite
+ -- deliberately not defined as an aliased object in the RM. This means
+ -- that it works fine to rewrite it as a call, without having to worry
+ -- about complications that would other arise from X'Priority'Access,
+ -- which is illegal, because of the lack of aliasing.
+
+ when Attribute_Priority =>
+ declare
+ Call : Node_Id;
+ Conctyp : Entity_Id;
+ Object_Parm : Node_Id;
+ Subprg : Entity_Id;
+ RT_Subprg_Name : Node_Id;
+
+ begin
+ -- Look for the enclosing concurrent type
+
+ Conctyp := Current_Scope;
+ while not Is_Concurrent_Type (Conctyp) loop
+ Conctyp := Scope (Conctyp);
+ end loop;
+
+ pragma Assert (Is_Protected_Type (Conctyp));
+
+ -- Generate the actual of the call
+
+ Subprg := Current_Scope;
+ while not Present (Protected_Body_Subprogram (Subprg)) loop
+ Subprg := Scope (Subprg);
+ end loop;
+
+ -- Use of 'Priority inside protected entries and barriers (in
+ -- both cases the type of the first formal of their expanded
+ -- subprogram is Address)
+
+ if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
+ = RTE (RE_Address)
+ then
+ declare
+ New_Itype : Entity_Id;
+
+ begin
+ -- In the expansion of protected entries the type of the
+ -- first formal of the Protected_Body_Subprogram is an
+ -- Address. In order to reference the _object component
+ -- we generate:
+
+ -- type T is access p__ptTV;
+ -- freeze T []
+
+ New_Itype := Create_Itype (E_Access_Type, N);
+ Set_Etype (New_Itype, New_Itype);
+ Set_Directly_Designated_Type (New_Itype,
+ Corresponding_Record_Type (Conctyp));
+ Freeze_Itype (New_Itype, N);
+
+ -- Generate:
+ -- T!(O)._object'unchecked_access
+
+ Object_Parm :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ Make_Selected_Component (Loc,
+ Prefix =>
+ Unchecked_Convert_To (New_Itype,
+ New_Reference_To
+ (First_Entity
+ (Protected_Body_Subprogram (Subprg)),
+ Loc)),
+ Selector_Name =>
+ Make_Identifier (Loc, Name_uObject)),
+ Attribute_Name => Name_Unchecked_Access);
+ end;
+
+ -- Use of 'Priority inside a protected subprogram
+
+ else
+ Object_Parm :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ Make_Selected_Component (Loc,
+ Prefix => New_Reference_To
+ (First_Entity
+ (Protected_Body_Subprogram (Subprg)),
+ Loc),
+ Selector_Name => Make_Identifier (Loc, Name_uObject)),
+ Attribute_Name => Name_Unchecked_Access);
+ end if;
+
+ -- Select the appropriate run-time subprogram
+
+ if Number_Entries (Conctyp) = 0 then
+ RT_Subprg_Name :=
+ New_Reference_To (RTE (RE_Get_Ceiling), Loc);
+ else
+ RT_Subprg_Name :=
+ New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
+ end if;
+
+ Call :=
+ Make_Function_Call (Loc,
+ Name => RT_Subprg_Name,
+ Parameter_Associations => New_List (Object_Parm));
+
+ Rewrite (N, Call);
+
+ -- Avoid the generation of extra checks on the pointer to the
+ -- protected object.
+
+ Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
+ end;
+
+ ------------------
+ -- Range_Length --
+ ------------------
+
+ when Attribute_Range_Length => Range_Length : 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 (Ptyp)
+ and then Has_Non_Standard_Rep (Ptyp)
+ 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 (Ptyp, Loc),
+ Expressions => New_List (
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Last,
+ Prefix => New_Occurrence_Of (Ptyp, Loc)))),
+
+ Right_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Pos,
+ Prefix => New_Occurrence_Of (Ptyp, Loc),
+ Expressions => New_List (
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_First,
+ Prefix => New_Occurrence_Of (Ptyp, Loc))))),
+
+ Right_Opnd => Make_Integer_Literal (Loc, 1)));
+
+ Analyze_And_Resolve (N, Typ);
+
+ -- For all other cases, the attribute is handled by the back end, 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_Stream_Subprogram (P_Type, TSS_Stream_Read);
+
+ 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_Stream_Convert_Pragma (P_Type);
+
+ if Present (Prag) then
+ Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
+ Rfunc := Entity (Expression (Arg2));
+ Lhs := Relocate_Node (Next (First (Exprs)));
+ Rhs :=
+ OK_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, TSS_Stream_Read);
+
+ -- 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));
+
+ -- Ada 2005 (AI-216): Program_Error is raised when executing
+ -- the default implementation of the Read attribute of an
+ -- Unchecked_Union type.
+
+ if Is_Unchecked_Union (Base_Type (U_Type)) then
+ Insert_Action (N,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Unchecked_Union_Restriction));
+ end if;
+
+ if Has_Discriminants (U_Type)
+ and then Present
+ (Discriminant_Default_Value (First_Discriminant (U_Type)))
+ then
+ Build_Mutable_Record_Read_Procedure
+ (Loc, Full_Base (U_Type), Decl, Pname);
+ else
+ Build_Record_Read_Procedure
+ (Loc, Full_Base (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;
+
+ ---------
+ -- Ref --
+ ---------
+
+ -- Ref is identical to To_Address, see To_Address for processing
+
+ ---------------
+ -- 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);
+
+ ------------
+ -- Result --
+ ------------
+
+ -- Transform 'Result into reference to _Result formal. At the point
+ -- where a legal 'Result attribute is expanded, we know that we are in
+ -- the context of a _Postcondition function with a _Result parameter.
+
+ when Attribute_Result =>
+ Rewrite (N, Make_Identifier (Loc, Chars => Name_uResult));
+ Analyze_And_Resolve (N, Typ);
+
+ -----------
+ -- 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);
+
+ ------------------
+ -- Same_Storage --
+ ------------------
+
+ when Attribute_Same_Storage => Same_Storage : declare
+ Loc : constant Source_Ptr := Sloc (N);
+
+ X : constant Node_Id := Prefix (N);
+ Y : constant Node_Id := First (Expressions (N));
+ -- The arguments
+
+ X_Addr, Y_Addr : Node_Id;
+ -- Rhe expressions for their addresses
+
+ X_Size, Y_Size : Node_Id;
+ -- Rhe expressions for their sizes
+
+ begin
+ -- The attribute is expanded as:
+
+ -- (X'address = Y'address)
+ -- and then (X'Size = Y'Size)
+
+ -- If both arguments have the same Etype the second conjunct can be
+ -- omitted.
+
+ X_Addr :=
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Address,
+ Prefix => New_Copy_Tree (X));
+
+ Y_Addr :=
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Address,
+ Prefix => New_Copy_Tree (Y));
+
+ X_Size :=
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Size,
+ Prefix => New_Copy_Tree (X));
+
+ Y_Size :=
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Size,
+ Prefix => New_Copy_Tree (Y));
+
+ if Etype (X) = Etype (Y) then
+ Rewrite (N,
+ (Make_Op_Eq (Loc,
+ Left_Opnd => X_Addr,
+ Right_Opnd => Y_Addr)));
+ else
+ Rewrite (N,
+ Make_Op_And (Loc,
+ Left_Opnd =>
+ Make_Op_Eq (Loc,
+ Left_Opnd => X_Addr,
+ Right_Opnd => Y_Addr),
+ Right_Opnd =>
+ Make_Op_Eq (Loc,
+ Left_Opnd => X_Size,
+ Right_Opnd => Y_Size)));
+ end if;
+
+ Analyze_And_Resolve (N, Standard_Boolean);
+ end Same_Storage;
+
+ -------------
+ -- 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);
+
+ -------------------------
+ -- Simple_Storage_Pool --
+ -------------------------
+
+ when Attribute_Simple_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);
+
+ ----------
+ -- Size --
+ ----------
+
+ when Attribute_Size |
+ Attribute_Object_Size |
+ Attribute_Value_Size |
+ Attribute_VADS_Size => Size :
+
+ declare
+ Siz : Uint;
+ New_Node : Node_Id;
+
+ 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 (Ptyp) or else Is_Constrained (Ptyp))
+ then
+ Rewrite (Pref, New_Occurrence_Of (Ptyp, 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 (Ptyp) and then No (Size_Clause (Ptyp)) 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, X'Class'Size is transformed into a direct
+ -- reference to the Size of the class type, so that the back end does
+ -- not have to deal with the X'Class'Size reference.
+
+ if Is_Entity_Name (Pref)
+ and then Is_Class_Wide_Type (Entity (Pref))
+ then
+ Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
+ return;
+
+ -- For X'Size applied to an object of a class-wide type, transform
+ -- X'Size into a call to the primitive operation _Size applied to X.
+
+ elsif Is_Class_Wide_Type (Ptyp)
+ or else (Id = Attribute_Size
+ and then Is_Tagged_Type (Ptyp)
+ and then Has_Unknown_Discriminants (Ptyp))
+ then
+ -- No need to do anything else compiling under restriction
+ -- No_Dispatching_Calls. During the semantic analysis we
+ -- already notified such violation.
+
+ if Restriction_Active (No_Dispatching_Calls) then
+ return;
+ end if;
+
+ 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;
+
+ -- Case of known RM_Size of a type
+
+ elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
+ and then Is_Entity_Name (Pref)
+ and then Is_Type (Entity (Pref))
+ and then Known_Static_RM_Size (Entity (Pref))
+ then
+ Siz := RM_Size (Entity (Pref));
+
+ -- Case of known Esize of a type
+
+ elsif Id = Attribute_Object_Size
+ and then Is_Entity_Name (Pref)
+ and then Is_Type (Entity (Pref))
+ and then Known_Static_Esize (Entity (Pref))
+ then
+ Siz := Esize (Entity (Pref));
+
+ -- Case of known size of object
+
+ elsif Id = Attribute_Size
+ and then Is_Entity_Name (Pref)
+ and then Is_Object (Entity (Pref))
+ and then Known_Esize (Entity (Pref))
+ and then Known_Static_Esize (Entity (Pref))
+ then
+ Siz := Esize (Entity (Pref));
+
+ -- 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 the back end
+
+ else
+ Apply_Universal_Integer_Attribute_Checks (N);
+
+ -- If Size is applied to a formal parameter that is of 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 (Ptyp)
+ and then Is_Packed (Ptyp)
+ 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;
+
+ -- If Size applies to a dereference of an access to unconstrained
+ -- packed array, the back end needs to see its unconstrained
+ -- nominal type, but also a hint to the actual constrained type.
+
+ if Nkind (Pref) = N_Explicit_Dereference
+ and then Is_Array_Type (Ptyp)
+ and then not Is_Constrained (Ptyp)
+ and then Is_Packed (Ptyp)
+ then
+ Set_Actual_Designated_Subtype (Pref,
+ Get_Actual_Subtype (Pref));
+ end if;
+
+ return;
+ end if;
+
+ -- Common processing for record and array component case
+
+ if Siz /= No_Uint and then Siz /= 0 then
+ declare
+ CS : constant Boolean := Comes_From_Source (N);
+
+ begin
+ Rewrite (N, Make_Integer_Literal (Loc, Siz));
+
+ -- This integer literal is not a static expression. We do not
+ -- call Analyze_And_Resolve here, because this would activate
+ -- the circuit for deciding that a static value was out of
+ -- range, and we don't want that.
+
+ -- So just manually set the type, mark the expression as non-
+ -- static, and then ensure that the result is checked properly
+ -- if the attribute comes from source (if it was internally
+ -- generated, we never need a constraint check).
+
+ Set_Etype (N, Typ);
+ Set_Is_Static_Expression (N, False);
+
+ if CS then
+ Apply_Constraint_Check (N, Typ);
+ end if;
+ end;
+ 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
+ Alloc_Op : Entity_Id := Empty;
+
+ 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
+
+ -- If the access type is associated with a simple storage pool
+ -- object, then attempt to locate the optional Storage_Size
+ -- function of the simple storage pool type. If not found,
+ -- then the result will default to zero.
+
+ if Present (Get_Rep_Pragma (Root_Type (Ptyp),
+ Name_Simple_Storage_Pool_Type))
+ then
+ declare
+ Pool_Type : constant Entity_Id :=
+ Base_Type (Etype (Entity (N)));
+
+ begin
+ Alloc_Op := Get_Name_Entity_Id (Name_Storage_Size);
+ while Present (Alloc_Op) loop
+ if Scope (Alloc_Op) = Scope (Pool_Type)
+ and then Present (First_Formal (Alloc_Op))
+ and then Etype (First_Formal (Alloc_Op)) = Pool_Type
+ then
+ exit;
+ end if;
+
+ Alloc_Op := Homonym (Alloc_Op);
+ end loop;
+ end;
+
+ -- In the normal Storage_Pool case, retrieve the primitive
+ -- function associated with the pool type.
+
+ else
+ Alloc_Op :=
+ Find_Prim_Op
+ (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
+ Attribute_Name (N));
+ end if;
+
+ -- If Storage_Size wasn't found (can only occur in the simple
+ -- storage pool case), then simply use zero for the result.
+
+ if not Present (Alloc_Op) then
+ Rewrite (N, Make_Integer_Literal (Loc, 0));
+
+ -- Otherwise, rewrite the allocator as a call to pool type's
+ -- Storage_Size function.
+
+ else
+ Rewrite (N,
+ OK_Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (Alloc_Op, Loc),
+
+ Parameter_Associations => New_List (
+ New_Reference_To
+ (Associated_Storage_Pool
+ (Root_Type (Ptyp)), Loc)))));
+ end if;
+
+ else
+ Rewrite (N, Make_Integer_Literal (Loc, 0));
+ end if;
+
+ Analyze_And_Resolve (N, Typ);
+
+ -- For tasks, we retrieve the size directly from the TCB. The
+ -- size may depend on a discriminant of the type, and therefore
+ -- can be a per-object expression, so type-level information is
+ -- not sufficient in general. There are four cases to consider:
+
+ -- a) If the attribute appears within a task body, the designated
+ -- TCB is obtained by a call to Self.
+
+ -- b) If the prefix of the attribute is the name of a task object,
+ -- the designated TCB is the one stored in the corresponding record.
+
+ -- c) If the prefix is a task type, the size is obtained from the
+ -- size variable created for each task type
+
+ -- d) If no storage_size was specified for the type , there is no
+ -- size variable, and the value is a system-specific default.
+
+ else
+ if In_Open_Scopes (Ptyp) then
+
+ -- Storage_Size (Self)
+
+ Rewrite (N,
+ Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
+ Parameter_Associations =>
+ New_List (
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (RTE (RE_Self), Loc))))));
+
+ elsif not Is_Entity_Name (Pref)
+ or else not Is_Type (Entity (Pref))
+ then
+ -- Storage_Size (Rec (Obj).Size)
+
+ Rewrite (N,
+ Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of (RTE (RE_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_uTask_Id))))));
+
+ elsif Present (Storage_Size_Variable (Ptyp)) then
+
+ -- Static storage size pragma given for type: retrieve value
+ -- from its allocated storage variable.
+
+ 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)))));
+ else
+ -- Get system default
+
+ Rewrite (N,
+ Convert_To (Typ,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of (
+ RTE (RE_Default_Stack_Size), Loc))));
+ end if;
+
+ Analyze_And_Resolve (N, Typ);
+ end if;
+ end Storage_Size;
+
+ -----------------
+ -- Stream_Size --
+ -----------------
+
+ when Attribute_Stream_Size =>
+ Rewrite (N,
+ Make_Integer_Literal (Loc, Intval => Get_Stream_Size (Ptyp)));
+ Analyze_And_Resolve (N, Typ);
+
+ ----------
+ -- 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
+ Etyp : constant Entity_Id := Base_Type (Ptyp);
+
+ begin
+
+ -- For enumeration types with non-standard representations, we
+ -- expand typ'Succ (x) into
+
+ -- Pos_To_Rep (Rep_To_Pos (x) + 1)
+
+ -- If the representation is contiguous, we compute instead
+ -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
+
+ if Is_Enumeration_Type (Ptyp)
+ and then Present (Enum_Pos_To_Rep (Etyp))
+ then
+ if Has_Contiguous_Rep (Etyp) then
+ Rewrite (N,
+ Unchecked_Convert_To (Ptyp,
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Make_Integer_Literal (Loc,
+ Enumeration_Rep (First_Literal (Ptyp))),
+ Right_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (TSS (Etyp, TSS_Rep_To_Pos), Loc),
+
+ Parameter_Associations =>
+ New_List (
+ Unchecked_Convert_To (Ptyp,
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Unchecked_Convert_To (Standard_Integer,
+ Relocate_Node (First (Exprs))),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc, 1))),
+ Rep_To_Pos_Flag (Ptyp, Loc))))));
+ else
+ -- Add Boolean parameter True, to request program errror if
+ -- we have a bad representation on our hands. Add False if
+ -- checks are suppressed.
+
+ Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
+ Rewrite (N,
+ Make_Indexed_Component (Loc,
+ Prefix =>
+ New_Reference_To
+ (Enum_Pos_To_Rep (Etyp), Loc),
+ Expressions => New_List (
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (TSS (Etyp, TSS_Rep_To_Pos), Loc),
+ Parameter_Associations => Exprs),
+ Right_Opnd => Make_Integer_Literal (Loc, 1)))));
+ end if;
+
+ 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 argument is marked as needing a range check or
+ -- overflow checking is enabled, we must generate a check.
+
+ elsif not Overflow_Checks_Suppressed (Ptyp)
+ or else Do_Range_Check (First (Exprs))
+ then
+ Set_Do_Range_Check (First (Exprs), False);
+ 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 := Ptyp;
+ Prefix_Is_Type := False;
+ end if;
+
+ if Is_Class_Wide_Type (Ttyp) then
+ Ttyp := Root_Type (Ttyp);
+ end if;
+
+ Ttyp := Underlying_Type (Ttyp);
+
+ -- Ada 2005: The type may be a synchronized tagged type, in which
+ -- case the tag information is stored in the corresponding record.
+
+ if Is_Concurrent_Type (Ttyp) then
+ Ttyp := Corresponding_Record_Type (Ttyp);
+ end if;
+
+ if Prefix_Is_Type then
+
+ -- For VMs we leave the type attribute unexpanded because
+ -- there's not a dispatching table to reference.
+
+ if Tagged_Type_Expansion then
+ Rewrite (N,
+ Unchecked_Convert_To (RTE (RE_Tag),
+ New_Reference_To
+ (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
+ Analyze_And_Resolve (N, RTE (RE_Tag));
+ end if;
+
+ -- Ada 2005 (AI-251): The use of 'Tag in the sources always
+ -- references the primary tag of the actual object. If 'Tag is
+ -- applied to class-wide interface objects we generate code that
+ -- displaces "this" to reference the base of the object.
+
+ elsif Comes_From_Source (N)
+ and then Is_Class_Wide_Type (Etype (Prefix (N)))
+ and then Is_Interface (Etype (Prefix (N)))
+ then
+ -- Generate:
+ -- (To_Tag_Ptr (Prefix'Address)).all
+
+ -- Note that Prefix'Address is recursively expanded into a call
+ -- to Base_Address (Obj.Tag)
+
+ -- Not needed for VM targets, since all handled by the VM
+
+ if Tagged_Type_Expansion then
+ Rewrite (N,
+ Make_Explicit_Dereference (Loc,
+ Unchecked_Convert_To (RTE (RE_Tag_Ptr),
+ Make_Attribute_Reference (Loc,
+ Prefix => Relocate_Node (Pref),
+ Attribute_Name => Name_Address))));
+ 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 (First_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
+ -- The prefix of Terminated is of a task interface class-wide type.
+ -- Generate:
+ -- terminated (Task_Id (Pref._disp_get_task_id));
+
+ if Ada_Version >= Ada_2005
+ and then Ekind (Ptyp) = E_Class_Wide_Type
+ and then Is_Interface (Ptyp)
+ and then Is_Task_Interface (Ptyp)
+ then
+ Rewrite (N,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (RTE (RE_Terminated), Loc),
+ Parameter_Associations => New_List (
+ Make_Unchecked_Type_Conversion (Loc,
+ Subtype_Mark =>
+ New_Reference_To (RTE (RO_ST_Task_Id), Loc),
+ Expression =>
+ Make_Selected_Component (Loc,
+ Prefix =>
+ New_Copy_Tree (Pref),
+ Selector_Name =>
+ Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
+
+ elsif 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) and System.Address'Ref (X) into
+ -- unchecked conversion from (integral) type of X to type address.
+
+ when Attribute_To_Address | Attribute_Ref =>
+ Rewrite (N,
+ Unchecked_Convert_To (RTE (RE_Address),
+ Relocate_Node (First (Exprs))));
+ Analyze_And_Resolve (N, RTE (RE_Address));
+
+ ------------
+ -- To_Any --
+ ------------
+
+ when Attribute_To_Any => To_Any : declare
+ P_Type : constant Entity_Id := Etype (Pref);
+ Decls : constant List_Id := New_List;
+ begin
+ Rewrite (N,
+ Build_To_Any_Call
+ (Loc,
+ Convert_To (P_Type,
+ Relocate_Node (First (Exprs))), Decls));
+ Insert_Actions (N, Decls);
+ Analyze_And_Resolve (N, RTE (RE_Any));
+ end To_Any;
+
+ ----------------
+ -- Truncation --
+ ----------------
+
+ -- Transforms 'Truncation into a call to the floating-point attribute
+ -- function Truncation in Fat_xxx (where xxx is the root type).
+ -- Expansion is avoided for cases the back end can handle directly.
+
+ when Attribute_Truncation =>
+ if not Is_Inline_Floating_Point_Attribute (N) then
+ Expand_Fpt_Attribute_R (N);
+ end if;
+
+ --------------
+ -- TypeCode --
+ --------------
+
+ when Attribute_TypeCode => TypeCode : declare
+ P_Type : constant Entity_Id := Etype (Pref);
+ Decls : constant List_Id := New_List;
+ begin
+ Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
+ Insert_Actions (N, Decls);
+ Analyze_And_Resolve (N, RTE (RE_TypeCode));
+ end TypeCode;
+
+ -----------------------
+ -- 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). Expansion is avoided for cases the back end can handle
+ -- directly.
+
+ when Attribute_Unbiased_Rounding =>
+ if not Is_Inline_Floating_Point_Attribute (N) then
+ Expand_Fpt_Attribute_R (N);
+ end if;
+
+ -----------------
+ -- UET_Address --
+ -----------------
+
+ when Attribute_UET_Address => UET_Address : declare
+ Ent : constant Entity_Id := Make_Temporary (Loc, '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));
+
+ -- Set entity as internal to ensure proper Sprint output of its
+ -- implicit importation.
+
+ Set_Is_Internal (Ent);
+
+ Rewrite (N,
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Occurrence_Of (Ent, Loc),
+ Attribute_Name => Name_Address));
+
+ Analyze_And_Resolve (N, Typ);
+ end UET_Address;
+
+ ------------
+ -- Update --
+ ------------
+
+ when Attribute_Update =>
+ Expand_Update_Attribute (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 the back end. 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
+ if Has_Contiguous_Rep (Etyp) then
+ declare
+ Rep_Node : constant Node_Id :=
+ Unchecked_Convert_To (Etyp,
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Make_Integer_Literal (Loc,
+ Enumeration_Rep (First_Literal (Etyp))),
+ Right_Opnd =>
+ (Convert_To (Standard_Integer,
+ Relocate_Node (First (Exprs))))));
+
+ begin
+ Rewrite (N,
+ Unchecked_Convert_To (Etyp,
+ Make_Op_Add (Loc,
+ Left_Opnd =>
+ Make_Integer_Literal (Loc,
+ Enumeration_Rep (First_Literal (Etyp))),
+ Right_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To
+ (TSS (Etyp, TSS_Rep_To_Pos), Loc),
+ Parameter_Associations => New_List (
+ Rep_Node,
+ Rep_To_Pos_Flag (Etyp, Loc))))));
+ end;
+
+ else
+ 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))))));
+ end if;
+
+ Analyze_And_Resolve (N, Typ);
+
+ -- If the argument is marked as requiring a range check then generate
+ -- it here.
+
+ elsif Do_Range_Check (First (Exprs)) then
+ Set_Do_Range_Check (First (Exprs), False);
+ Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
+ 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
+ Btyp : Entity_Id := Base_Type (Ptyp);
+ Tst : Node_Id;
+
+ Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
+ -- Save the validity checking mode. We always turn off validity
+ -- checking during process of 'Valid since this is one place
+ -- where we do not want the implicit validity checks to intefere
+ -- with the explicit validity check that the programmer is doing.
+
+ function Make_Range_Test return Node_Id;
+ -- Build the code for a range test of the form
+ -- Btyp!(Pref) in Btyp!(Ptyp'First) .. Btyp!(Ptyp'Last)
+
+ ---------------------
+ -- Make_Range_Test --
+ ---------------------
+
+ function Make_Range_Test return Node_Id is
+ Temp : constant Node_Id := Duplicate_Subexpr (Pref);
+
+ begin
+ -- The value whose validity is being checked has been captured in
+ -- an object declaration. We certainly don't want this object to
+ -- appear valid because the declaration initializes it!
+
+ if Is_Entity_Name (Temp) then
+ Set_Is_Known_Valid (Entity (Temp), False);
+ end if;
+
+ return
+ Make_In (Loc,
+ Left_Opnd =>
+ Unchecked_Convert_To (Btyp, Temp),
+ Right_Opnd =>
+ Make_Range (Loc,
+ Low_Bound =>
+ Unchecked_Convert_To (Btyp,
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Occurrence_Of (Ptyp, Loc),
+ Attribute_Name => Name_First)),
+ High_Bound =>
+ 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
+ -- Do not expand sourced code 'Valid reference in CodePeer mode,
+ -- will be handled by the back-end directly.
+
+ if CodePeer_Mode and then Comes_From_Source (N) then
+ return;
+ end if;
+
+ -- Turn off validity checks. We do not want any implicit validity
+ -- checks to intefere with the explicit check from the attribute
+
+ Validity_Checks_On := False;
+
+ -- Retrieve the base type. Handle the case where the base type is a
+ -- private enumeration type.
+
+ if Is_Private_Type (Btyp) and then Present (Full_View (Btyp)) then
+ Btyp := Full_View (Btyp);
+ end if;
+
+ -- 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
+ Pkg : RE_Id;
+ Ftp : Entity_Id;
+
+ begin
+ case Float_Rep (Btyp) is
+
+ -- For vax fpt types, call appropriate routine in special
+ -- vax floating point unit. No need to worry about loads in
+ -- this case, since these types have no signalling NaN's.
+
+ when VAX_Native => Expand_Vax_Valid (N);
+
+ -- The AAMP back end handles Valid for floating-point types
+
+ when AAMP =>
+ Analyze_And_Resolve (Pref, Ptyp);
+ Set_Etype (N, Standard_Boolean);
+ Set_Analyzed (N);
+
+ when IEEE_Binary =>
+ Find_Fat_Info (Ptyp, Ftp, Pkg);
+
+ -- If the floating-point object might be unaligned, we
+ -- need to call the special routine Unaligned_Valid,
+ -- which makes the needed copy, being careful not to
+ -- load the value into any floating-point register.
+ -- The argument in this case is obj'Address (see
+ -- Unaligned_Valid routine in Fat_Gen).
+
+ if Is_Possibly_Unaligned_Object (Pref) then
+ Expand_Fpt_Attribute
+ (N, Pkg, Name_Unaligned_Valid,
+ New_List (
+ Make_Attribute_Reference (Loc,
+ Prefix => Relocate_Node (Pref),
+ Attribute_Name => Name_Address)));
+
+ -- In the normal case where we are sure the object is
+ -- aligned, we generate a call to Valid, and the argument
+ -- in this case is obj'Unrestricted_Access (after
+ -- converting obj to the right floating-point type).
+
+ else
+ Expand_Fpt_Attribute
+ (N, Pkg, Name_Valid,
+ New_List (
+ Make_Attribute_Reference (Loc,
+ Prefix => Unchecked_Convert_To (Ftp, Pref),
+ Attribute_Name => Name_Unrestricted_Access)));
+ end if;
+ end case;
+
+ -- 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 in the resulting
+ -- rep_to_pos call, 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 (Btyp))
+ then
+ Tst :=
+ Make_Op_Ge (Loc,
+ Left_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Reference_To (TSS (Btyp, TSS_Rep_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 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;
+
+ -- If a predicate is present, then we do the predicate test, even if
+ -- within the predicate function (infinite recursion is warned about
+ -- in Sem_Attr in that case).
+
+ declare
+ Pred_Func : constant Entity_Id := Predicate_Function (Ptyp);
+
+ begin
+ if Present (Pred_Func) then
+ Rewrite (N,
+ Make_And_Then (Loc,
+ Left_Opnd => Relocate_Node (N),
+ Right_Opnd => Make_Predicate_Call (Ptyp, Pref)));
+ end if;
+ end;
+
+ Analyze_And_Resolve (N, Standard_Boolean);
+ Validity_Checks_On := Save_Validity_Checks_On;
+ end Valid;
+
+ -------------------
+ -- Valid_Scalars --
+ -------------------
+
+ when Attribute_Valid_Scalars => Valid_Scalars : declare
+ Ftyp : Entity_Id;
+
+ begin
+ if Present (Underlying_Type (Ptyp)) then
+ Ftyp := Underlying_Type (Ptyp);
+ else
+ Ftyp := Ptyp;
+ end if;
+
+ -- For scalar types, Valid_Scalars is the same as Valid
+
+ if Is_Scalar_Type (Ftyp) then
+ Rewrite (N,
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => Name_Valid,
+ Prefix => Pref));
+ Analyze_And_Resolve (N, Standard_Boolean);
+
+ -- For array types, we construct a function that determines if there
+ -- are any non-valid scalar subcomponents, and call the function.
+ -- We only do this for arrays whose component type needs checking
+
+ elsif Is_Array_Type (Ftyp)
+ and then not No_Scalar_Parts (Component_Type (Ftyp))
+ then
+ Rewrite (N,
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of (Build_Array_VS_Func (Ftyp, N), Loc),
+ Parameter_Associations => New_List (Pref)));
+
+ Analyze_And_Resolve (N, Standard_Boolean);
+
+ -- For record types, we build a big if expression, applying Valid or
+ -- Valid_Scalars as appropriate to all relevant components.
+
+ elsif (Is_Record_Type (Ptyp) or else Has_Discriminants (Ptyp))
+ and then not No_Scalar_Parts (Ptyp)
+ then
+ declare
+ C : Entity_Id;
+ X : Node_Id;
+ A : Name_Id;
+
+ begin
+ X := New_Occurrence_Of (Standard_True, Loc);
+ C := First_Component_Or_Discriminant (Ptyp);
+ while Present (C) loop
+ if No_Scalar_Parts (Etype (C)) then
+ goto Continue;
+ elsif Is_Scalar_Type (Etype (C)) then
+ A := Name_Valid;
+ else
+ A := Name_Valid_Scalars;
+ end if;
+
+ X :=
+ Make_And_Then (Loc,
+ Left_Opnd => X,
+ Right_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Attribute_Name => A,
+ Prefix =>
+ Make_Selected_Component (Loc,
+ Prefix =>
+ Duplicate_Subexpr (Pref, Name_Req => True),
+ Selector_Name =>
+ New_Occurrence_Of (C, Loc))));
+ <<Continue>>
+ Next_Component_Or_Discriminant (C);
+ end loop;
+
+ Rewrite (N, X);
+ Analyze_And_Resolve (N, Standard_Boolean);
+ end;
+
+ -- For all other types, result is True (but not static)
+
+ else
+ Rewrite (N, New_Occurrence_Of (Standard_Boolean, Loc));
+ Analyze_And_Resolve (N, Standard_Boolean);
+ Set_Is_Static_Expression (N, False);
+ end if;
+ end Valid_Scalars;
+
+ -----------
+ -- Value --
+ -----------
+
+ -- Value attribute is handled in separate unit 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 --
+ ----------------
+
+ -- Wide_Image attribute is handled in separate unit Exp_Imgv
+
+ when Attribute_Wide_Image =>
+ Exp_Imgv.Expand_Wide_Image_Attribute (N);
+
+ ---------------------
+ -- Wide_Wide_Image --
+ ---------------------
+
+ -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
+
+ when Attribute_Wide_Wide_Image =>
+ Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
+
+ ----------------
+ -- 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.
+
+ -- Note: for this approach to be fully standard compliant for the cases
+ -- where typ is Wide_Character and Wide_Wide_Character, the encoding
+ -- method must cover the entire character range (e.g. UTF-8). But that
+ -- is a reasonable requirement when dealing with encoded character
+ -- sequences. Presumably if one of the restrictive encoding mechanisms
+ -- is in use such as Shift-JIS, then characters that cannot be
+ -- represented using this encoding will not appear in any case.
+
+ 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_Wide_Value --
+ ---------------------
+
+ -- We expand typ'Wide_Value_Value (X) into
+
+ -- typ'Value
+ -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
+
+ -- Wide_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_Wide_Value in all cases, and results in a
+ -- very simple implementation approach.
+
+ -- It's not quite right where typ = Wide_Wide_Character, because the
+ -- encoding method may not cover the whole character type ???
+
+ when Attribute_Wide_Wide_Value => Wide_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_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_Wide_Value;
+
+ ---------------------
+ -- Wide_Wide_Width --
+ ---------------------
+
+ -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
+
+ when Attribute_Wide_Wide_Width =>
+ Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
+
+ ----------------
+ -- Wide_Width --
+ ----------------
+
+ -- Wide_Width attribute is handled in separate unit Exp_Imgv
+
+ when Attribute_Wide_Width =>
+ Exp_Imgv.Expand_Width_Attribute (N, Wide);
+
+ -----------
+ -- Width --
+ -----------
+
+ -- Width attribute is handled in separate unit Exp_Imgv
+
+ when Attribute_Width =>
+ Exp_Imgv.Expand_Width_Attribute (N, Normal);
+
+ -----------
+ -- 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_Stream_Subprogram (P_Type, TSS_Stream_Write);
+
+ 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_Stream_Convert_Pragma (P_Type);
+
+ 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 (
+ OK_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, TSS_Stream_Write);
+
+ -- 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));
+
+ -- Ada 2005 (AI-216): Program_Error is raised when executing
+ -- the default implementation of the Write attribute of an
+ -- Unchecked_Union type. However, if the 'Write reference is
+ -- within the generated Output stream procedure, Write outputs
+ -- the components, and the default values of the discriminant
+ -- are streamed by the Output procedure itself.
+
+ if Is_Unchecked_Union (Base_Type (U_Type))
+ and not Is_TSS (Current_Scope, TSS_Stream_Output)
+ then
+ Insert_Action (N,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Unchecked_Union_Restriction));
+ end if;
+
+ if Has_Discriminants (U_Type)
+ and then Present
+ (Discriminant_Default_Value (First_Discriminant (U_Type)))
+ then
+ Build_Mutable_Record_Write_Procedure
+ (Loc, Full_Base (U_Type), Decl, Pname);
+ else
+ Build_Record_Write_Procedure
+ (Loc, Full_Base (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 the back end, 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 the back end would otherwise get
+ -- confused by the equivalent packed array type.
+
+ when Attribute_Component_Size =>
+ null;
+
+ -- The following attributes are handled by the back end (except that
+ -- static cases have already been evaluated during semantic processing,
+ -- but in any case the back end should not count on this). The one bit
+ -- of special processing required is that these attributes typically
+ -- generate conditionals in the code, so we need to check the relevant
+ -- restriction.
+
+ when Attribute_Max |
+ Attribute_Min =>
+ Check_Restriction (No_Implicit_Conditionals, N);
+
+ -- The following attributes are handled by the back end (except that
+ -- static cases have already been evaluated during semantic processing,
+ -- but in any case the back end should not count on this).
+
+ -- The back end also handles the non-class-wide cases of Size
+
+ when Attribute_Bit_Order |
+ Attribute_Code_Address |
+ Attribute_Definite |
+ Attribute_Null_Parameter |
+ Attribute_Passed_By_Reference |
+ Attribute_Pool_Address |
+ Attribute_Scalar_Storage_Order =>
+ null;
+
+ -- The following attributes are also handled by the back end, but return
+ -- a universal integer result, so may need a conversion for checking
+ -- that the result is in range.
+
+ when Attribute_Aft |
+ Attribute_Max_Alignment_For_Allocation =>
+ 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_Atomic_Always_Lock_Free |
+ Attribute_Base |
+ Attribute_Class |
+ Attribute_Compiler_Version |
+ Attribute_Default_Bit_Order |
+ Attribute_Delta |
+ Attribute_Denorm |
+ Attribute_Digits |
+ Attribute_Emax |
+ Attribute_Enabled |
+ Attribute_Epsilon |
+ Attribute_Fast_Math |
+ Attribute_First_Valid |
+ Attribute_Has_Access_Values |
+ Attribute_Has_Discriminants |
+ Attribute_Has_Tagged_Values |
+ Attribute_Large |
+ Attribute_Last_Valid |
+ Attribute_Lock_Free |
+ Attribute_Machine_Emax |
+ Attribute_Machine_Emin |
+ Attribute_Machine_Mantissa |
+ Attribute_Machine_Overflows |
+ Attribute_Machine_Radix |
+ Attribute_Machine_Rounds |
+ 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_Stub_Type |
+ Attribute_System_Allocator_Alignment |
+ Attribute_Target_Name |
+ Attribute_Type_Class |
+ Attribute_Type_Key |
+ Attribute_Unconstrained_Array |
+ 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 the back end will never see these either.
+
+ when Attribute_Asm_Input |
+ Attribute_Asm_Output =>
+ null;
+ end case;
+
+ -- Note: as mentioned earlier, individual sections of the above case
+ -- statement assume there is no code after the case statement, and are
+ -- legitimately allowed to execute return statements if they have nothing
+ -- more to do, so DO NOT add code at this point.
+
+ exception
+ when RE_Not_Available =>
+ return;
+ 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.
+ -- We also suppress these checks if we are the right side of an assignment
+ -- statement or the expression of an object declaration, where the flag
+ -- Suppress_Assignment_Checks is set for the assignment/declaration.
+
+ procedure Expand_Pred_Succ (N : Node_Id) is
+ Loc : constant Source_Ptr := Sloc (N);
+ P : constant Node_Id := Parent (N);
+ Cnam : Name_Id;
+
+ begin
+ if Attribute_Name (N) = Name_Pred then
+ Cnam := Name_First;
+ else
+ Cnam := Name_Last;
+ end if;
+
+ if not Nkind_In (P, N_Assignment_Statement, N_Object_Declaration)
+ or else not Suppress_Assignment_Checks (P)
+ then
+ Insert_Action (N,
+ Make_Raise_Constraint_Error (Loc,
+ Condition =>
+ Make_Op_Eq (Loc,
+ Left_Opnd =>
+ Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
+ Right_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
+ Attribute_Name => Cnam)),
+ Reason => CE_Overflow_Check_Failed));
+ end if;
+ end Expand_Pred_Succ;
+
+ -----------------------------
+ -- Expand_Update_Attribute --
+ -----------------------------
+
+ procedure Expand_Update_Attribute (N : Node_Id) is
+ procedure Process_Component_Or_Element_Update
+ (Temp : Entity_Id;
+ Comp : Node_Id;
+ Expr : Node_Id;
+ Typ : Entity_Id);
+ -- Generate the statements necessary to update a single component or an
+ -- element of the prefix. The code is inserted before the attribute N.
+ -- Temp denotes the entity of the anonymous object created to reflect
+ -- the changes in values. Comp is the component/index expression to be
+ -- updated. Expr is an expression yielding the new value of Comp. Typ
+ -- is the type of the prefix of attribute Update.
+
+ procedure Process_Range_Update
+ (Temp : Entity_Id;
+ Comp : Node_Id;
+ Expr : Node_Id);
+ -- Generate the statements necessary to update a slice of the prefix.
+ -- The code is inserted before the attribute N. Temp denotes the entity
+ -- of the anonymous object created to reflect the changes in values.
+ -- Comp is range of the slice to be updated. Expr is an expression
+ -- yielding the new value of Comp.
+
+ -----------------------------------------
+ -- Process_Component_Or_Element_Update --
+ -----------------------------------------
+
+ procedure Process_Component_Or_Element_Update
+ (Temp : Entity_Id;
+ Comp : Node_Id;
+ Expr : Node_Id;
+ Typ : Entity_Id)
+ is
+ Loc : constant Source_Ptr := Sloc (Comp);
+ Exprs : List_Id;
+ LHS : Node_Id;
+
+ begin
+ -- An array element may be modified by the following relations
+ -- depending on the number of dimensions:
+
+ -- 1 => Expr -- one dimensional update
+ -- (1, ..., N) => Expr -- multi dimensional update
+
+ -- The above forms are converted in assignment statements where the
+ -- left hand side is an indexed component:
+
+ -- Temp (1) := Expr; -- one dimensional update
+ -- Temp (1, ..., N) := Expr; -- multi dimensional update
+
+ if Is_Array_Type (Typ) then
+
+ -- The index expressions of a multi dimensional array update
+ -- appear as an aggregate.
+
+ if Nkind (Comp) = N_Aggregate then
+ Exprs := New_Copy_List_Tree (Expressions (Comp));
+ else
+ Exprs := New_List (Relocate_Node (Comp));
+ end if;
+
+ LHS :=
+ Make_Indexed_Component (Loc,
+ Prefix => New_Reference_To (Temp, Loc),
+ Expressions => Exprs);
+
+ -- A record component update appears in the following form:
+
+ -- Comp => Expr
+
+ -- The above relation is transformed into an assignment statement
+ -- where the left hand side is a selected component:
+
+ -- Temp.Comp := Expr;
+
+ else pragma Assert (Is_Record_Type (Typ));
+ LHS :=
+ Make_Selected_Component (Loc,
+ Prefix => New_Reference_To (Temp, Loc),
+ Selector_Name => Relocate_Node (Comp));
+ end if;
+
+ Insert_Action (N,
+ Make_Assignment_Statement (Loc,
+ Name => LHS,
+ Expression => Relocate_Node (Expr)));
+ end Process_Component_Or_Element_Update;
+
+ --------------------------
+ -- Process_Range_Update --
+ --------------------------
+
+ procedure Process_Range_Update
+ (Temp : Entity_Id;
+ Comp : Node_Id;
+ Expr : Node_Id)
+ is
+ Loc : constant Source_Ptr := Sloc (Comp);
+ Index : Entity_Id;
+
+ begin
+ -- A range update appears as
+
+ -- (Low .. High => Expr)
+
+ -- The above construct is transformed into a loop that iterates over
+ -- the given range and modifies the corresponding array values to the
+ -- value of Expr:
+
+ -- for Index in Low .. High loop
+ -- Temp (Index) := Expr;
+ -- end loop;
+
+ Index := Make_Temporary (Loc, 'I');
+
+ Insert_Action (N,
+ Make_Loop_Statement (Loc,
+ Iteration_Scheme =>
+ Make_Iteration_Scheme (Loc,
+ Loop_Parameter_Specification =>
+ Make_Loop_Parameter_Specification (Loc,
+ Defining_Identifier => Index,
+ Discrete_Subtype_Definition => Relocate_Node (Comp))),
+
+ Statements => New_List (
+ Make_Assignment_Statement (Loc,
+ Name =>
+ Make_Indexed_Component (Loc,
+ Prefix => New_Reference_To (Temp, Loc),
+ Expressions => New_List (New_Reference_To (Index, Loc))),
+ Expression => Relocate_Node (Expr))),
+
+ End_Label => Empty));
+ end Process_Range_Update;
+
+ -- Local variables
+
+ Aggr : constant Node_Id := First (Expressions (N));
+ Loc : constant Source_Ptr := Sloc (N);
+ Pref : constant Node_Id := Prefix (N);
+ Typ : constant Entity_Id := Etype (Pref);
+ Assoc : Node_Id;
+ Comp : Node_Id;
+ Expr : Node_Id;
+ Temp : Entity_Id;
+
+ -- Start of processing for Expand_Update_Attribute
+
+ begin
+ -- Create the anonymous object that stores the value of the prefix and
+ -- reflects subsequent changes in value. Generate:
+
+ -- Temp : <type of Pref> := Pref;
+
+ Temp := Make_Temporary (Loc, 'T');
+
+ Insert_Action (N,
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Temp,
+ Object_Definition => New_Reference_To (Typ, Loc),
+ Expression => Relocate_Node (Pref)));
+
+ -- Process the update aggregate
+
+ Assoc := First (Component_Associations (Aggr));
+ while Present (Assoc) loop
+ Comp := First (Choices (Assoc));
+ Expr := Expression (Assoc);
+ while Present (Comp) loop
+ if Nkind (Comp) = N_Range then
+ Process_Range_Update (Temp, Comp, Expr);
+ else
+ Process_Component_Or_Element_Update (Temp, Comp, Expr, Typ);
+ end if;
+
+ Next (Comp);
+ end loop;
+
+ Next (Assoc);
+ end loop;
+
+ -- The attribute is replaced by a reference to the anonymous object
+
+ Rewrite (N, New_Reference_To (Temp, Loc));
+ Analyze (N);
+ end Expand_Update_Attribute;
+
+ -------------------
+ -- Find_Fat_Info --
+ -------------------
+
+ procedure Find_Fat_Info
+ (T : Entity_Id;
+ Fat_Type : out Entity_Id;
+ Fat_Pkg : out RE_Id)
+ is
+ Btyp : constant Entity_Id := Base_Type (T);
+ Rtyp : constant Entity_Id := Root_Type (T);
+ Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
+
+ begin
+ -- If the base type is VAX float, then get appropriate VAX float type
+
+ if Vax_Float (Btyp) then
+ case Digs is
+ when 6 =>
+ Fat_Type := RTE (RE_Fat_VAX_F);
+ Fat_Pkg := RE_Attr_VAX_F_Float;
+
+ when 9 =>
+ Fat_Type := RTE (RE_Fat_VAX_D);
+ Fat_Pkg := RE_Attr_VAX_D_Float;
+
+ when 15 =>
+ Fat_Type := RTE (RE_Fat_VAX_G);
+ Fat_Pkg := RE_Attr_VAX_G_Float;
+
+ when others =>
+ raise Program_Error;
+ end case;
+
+ -- If root type is VAX float, this is the case where the library has
+ -- been recompiled in VAX float mode, and we have an IEEE float type.
+ -- This is when we use the special IEEE Fat packages.
+
+ elsif Vax_Float (Rtyp) then
+ case Digs is
+ when 6 =>
+ Fat_Type := RTE (RE_Fat_IEEE_Short);
+ Fat_Pkg := RE_Attr_IEEE_Short;
+
+ when 15 =>
+ Fat_Type := RTE (RE_Fat_IEEE_Long);
+ Fat_Pkg := RE_Attr_IEEE_Long;
+
+ when others =>
+ raise Program_Error;
+ end case;
+
+ -- If neither the base type nor the root type is VAX_Native then VAX
+ -- float is out of the picture, and we can just use the root type.
+
+ else
+ Fat_Type := Rtyp;
+
+ if Fat_Type = Standard_Short_Float then
+ Fat_Pkg := RE_Attr_Short_Float;
+
+ elsif Fat_Type = Standard_Float then
+ Fat_Pkg := RE_Attr_Float;
+
+ elsif Fat_Type = Standard_Long_Float then
+ Fat_Pkg := RE_Attr_Long_Float;
+
+ elsif Fat_Type = Standard_Long_Long_Float then
+ Fat_Pkg := RE_Attr_Long_Long_Float;
+
+ -- Universal real (which is its own root type) is treated as being
+ -- equivalent to Standard.Long_Long_Float, since it is defined to
+ -- have the same precision as the longest Float type.
+
+ elsif Fat_Type = Universal_Real then
+ Fat_Type := Standard_Long_Long_Float;
+ Fat_Pkg := RE_Attr_Long_Long_Float;
+
+ else
+ raise Program_Error;
+ end if;
+ end if;
+ end Find_Fat_Info;
+
+ ----------------------------
+ -- Find_Stream_Subprogram --
+ ----------------------------
+
+ function Find_Stream_Subprogram
+ (Typ : Entity_Id;
+ Nam : TSS_Name_Type) return Entity_Id
+ is
+ Base_Typ : constant Entity_Id := Base_Type (Typ);
+ Ent : constant Entity_Id := TSS (Typ, Nam);
+
+ function Is_Available (Entity : RE_Id) return Boolean;
+ pragma Inline (Is_Available);
+ -- Function to check whether the specified run-time call is available
+ -- in the run time used. In the case of a configurable run time, it
+ -- is normal that some subprograms are not there.
+
+ -- I don't understand this routine at all, why is this not just a
+ -- call to RTE_Available? And if for some reason we need a different
+ -- routine with different semantics, why is not in Rtsfind ???
+
+ ------------------
+ -- Is_Available --
+ ------------------
+
+ function Is_Available (Entity : RE_Id) return Boolean is
+ begin
+ -- Assume that the unit will always be available when using a
+ -- "normal" (not configurable) run time.
+
+ return not Configurable_Run_Time_Mode
+ or else RTE_Available (Entity);
+ end Is_Available;
+
+ -- Start of processing for Find_Stream_Subprogram
+
+ begin
+ if Present (Ent) then
+ return Ent;
+ end if;
+
+ -- Stream attributes for strings are expanded into library calls. The
+ -- following checks are disabled when the run-time is not available or
+ -- when compiling predefined types due to bootstrap issues. As a result,
+ -- the compiler will generate in-place stream routines for string types
+ -- that appear in GNAT's library, but will generate calls via rtsfind
+ -- to library routines for user code.
+
+ -- ??? For now, disable this code for JVM, since this generates a
+ -- VerifyError exception at run time on e.g. c330001.
+
+ -- This is disabled for AAMP, to avoid creating dependences on files not
+ -- supported in the AAMP library (such as s-fileio.adb).
+
+ -- Note: In the case of using a configurable run time, it is very likely
+ -- that stream routines for string types are not present (they require
+ -- file system support). In this case, the specific stream routines for
+ -- strings are not used, relying on the regular stream mechanism
+ -- instead. That is why we include the test Is_Available when dealing
+ -- with these cases.
+
+ if VM_Target /= JVM_Target
+ and then not AAMP_On_Target
+ and then
+ not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
+ then
+ -- String as defined in package Ada
+
+ if Base_Typ = Standard_String then
+ if Restriction_Active (No_Stream_Optimizations) then
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_String_Input)
+ then
+ return RTE (RE_String_Input);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_String_Output)
+ then
+ return RTE (RE_String_Output);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_String_Read)
+ then
+ return RTE (RE_String_Read);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_String_Write)
+ then
+ return RTE (RE_String_Write);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+
+ else
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_String_Input_Blk_IO)
+ then
+ return RTE (RE_String_Input_Blk_IO);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_String_Output_Blk_IO)
+ then
+ return RTE (RE_String_Output_Blk_IO);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_String_Read_Blk_IO)
+ then
+ return RTE (RE_String_Read_Blk_IO);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_String_Write_Blk_IO)
+ then
+ return RTE (RE_String_Write_Blk_IO);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+ end if;
+
+ -- Wide_String as defined in package Ada
+
+ elsif Base_Typ = Standard_Wide_String then
+ if Restriction_Active (No_Stream_Optimizations) then
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_Wide_String_Input)
+ then
+ return RTE (RE_Wide_String_Input);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_Wide_String_Output)
+ then
+ return RTE (RE_Wide_String_Output);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_Wide_String_Read)
+ then
+ return RTE (RE_Wide_String_Read);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_Wide_String_Write)
+ then
+ return RTE (RE_Wide_String_Write);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+
+ else
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_Wide_String_Input_Blk_IO)
+ then
+ return RTE (RE_Wide_String_Input_Blk_IO);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_Wide_String_Output_Blk_IO)
+ then
+ return RTE (RE_Wide_String_Output_Blk_IO);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_Wide_String_Read_Blk_IO)
+ then
+ return RTE (RE_Wide_String_Read_Blk_IO);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_Wide_String_Write_Blk_IO)
+ then
+ return RTE (RE_Wide_String_Write_Blk_IO);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+ end if;
+
+ -- Wide_Wide_String as defined in package Ada
+
+ elsif Base_Typ = Standard_Wide_Wide_String then
+ if Restriction_Active (No_Stream_Optimizations) then
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_Wide_Wide_String_Input)
+ then
+ return RTE (RE_Wide_Wide_String_Input);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_Wide_Wide_String_Output)
+ then
+ return RTE (RE_Wide_Wide_String_Output);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_Wide_Wide_String_Read)
+ then
+ return RTE (RE_Wide_Wide_String_Read);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_Wide_Wide_String_Write)
+ then
+ return RTE (RE_Wide_Wide_String_Write);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+
+ else
+ if Nam = TSS_Stream_Input
+ and then Is_Available (RE_Wide_Wide_String_Input_Blk_IO)
+ then
+ return RTE (RE_Wide_Wide_String_Input_Blk_IO);
+
+ elsif Nam = TSS_Stream_Output
+ and then Is_Available (RE_Wide_Wide_String_Output_Blk_IO)
+ then
+ return RTE (RE_Wide_Wide_String_Output_Blk_IO);
+
+ elsif Nam = TSS_Stream_Read
+ and then Is_Available (RE_Wide_Wide_String_Read_Blk_IO)
+ then
+ return RTE (RE_Wide_Wide_String_Read_Blk_IO);
+
+ elsif Nam = TSS_Stream_Write
+ and then Is_Available (RE_Wide_Wide_String_Write_Blk_IO)
+ then
+ return RTE (RE_Wide_Wide_String_Write_Blk_IO);
+
+ elsif Nam /= TSS_Stream_Input and then
+ Nam /= TSS_Stream_Output and then
+ Nam /= TSS_Stream_Read and then
+ Nam /= TSS_Stream_Write
+ then
+ raise Program_Error;
+ end if;
+ end if;
+ end if;
+ end if;
+
+ if Is_Tagged_Type (Typ)
+ and then Is_Derived_Type (Typ)
+ then
+ return Find_Prim_Op (Typ, Nam);
+ else
+ return Find_Inherited_TSS (Typ, Nam);
+ end if;
+ end Find_Stream_Subprogram;
+
+ ---------------
+ -- Full_Base --
+ ---------------
+
+ function Full_Base (T : Entity_Id) return Entity_Id is
+ BT : Entity_Id;
+
+ begin
+ BT := Base_Type (T);
+
+ if Is_Private_Type (BT)
+ and then Present (Full_View (BT))
+ then
+ BT := Full_View (BT);
+ end if;
+
+ return BT;
+ end Full_Base;
+
+ -----------------------
+ -- 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;
+
+ -------------------------------
+ -- Get_Stream_Convert_Pragma --
+ -------------------------------
+
+ function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
+ Typ : Entity_Id;
+ N : Node_Id;
+
+ begin
+ -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
+ -- that a stream convert pragma for a tagged type is not inherited from
+ -- its parent. Probably what is wrong here is that it is basically
+ -- incorrect to consider a stream convert pragma to be a representation
+ -- pragma at all ???
+
+ N := First_Rep_Item (Implementation_Base_Type (T));
+ while Present (N) loop
+ if Nkind (N) = N_Pragma
+ and then Pragma_Name (N) = Name_Stream_Convert
+ then
+ -- For tagged types this pragma is not inherited, so we
+ -- must verify that it is defined for the given type and
+ -- not an ancestor.
+
+ Typ :=
+ Entity (Expression (First (Pragma_Argument_Associations (N))));
+
+ if not Is_Tagged_Type (T)
+ or else T = Typ
+ or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
+ then
+ return N;
+ end if;
+ end if;
+
+ Next_Rep_Item (N);
+ end loop;
+
+ return Empty;
+ end Get_Stream_Convert_Pragma;
+
+ ---------------------------------
+ -- 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;
+
+ ----------------------------------------
+ -- Is_Inline_Floating_Point_Attribute --
+ ----------------------------------------
+
+ function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
+ Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
+
+ begin
+ if Nkind (Parent (N)) /= N_Type_Conversion
+ or else not Is_Integer_Type (Etype (Parent (N)))
+ then
+ return False;
+ end if;
+
+ -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
+ -- required back end support has not been implemented yet ???
+
+ return Id = Attribute_Truncation;
+ end Is_Inline_Floating_Point_Attribute;
+
+end Exp_Attr;