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author | Dan Albert <danalbert@google.com> | 2015-06-17 11:09:54 -0700 |
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committer | Dan Albert <danalbert@google.com> | 2015-06-17 14:15:22 -0700 |
commit | f378ebf14df0952eae870c9865bab8326aa8f137 (patch) | |
tree | 31794503eb2a8c64ea5f313b93100f1163afcffb /gcc-4.4.0/gcc/ada/exp_attr.adb | |
parent | 2c58169824949d3a597d9fa81931e001ef9b1bd0 (diff) | |
download | toolchain_gcc-f378ebf14df0952eae870c9865bab8326aa8f137.tar.gz toolchain_gcc-f378ebf14df0952eae870c9865bab8326aa8f137.tar.bz2 toolchain_gcc-f378ebf14df0952eae870c9865bab8326aa8f137.zip |
Delete old versions of GCC.
Change-Id: I710f125d905290e1024cbd67f48299861790c66c
Diffstat (limited to 'gcc-4.4.0/gcc/ada/exp_attr.adb')
-rw-r--r-- | gcc-4.4.0/gcc/ada/exp_attr.adb | 5660 |
1 files changed, 0 insertions, 5660 deletions
diff --git a/gcc-4.4.0/gcc/ada/exp_attr.adb b/gcc-4.4.0/gcc/ada/exp_attr.adb deleted file mode 100644 index d36667f91..000000000 --- a/gcc-4.4.0/gcc/ada/exp_attr.adb +++ /dev/null @@ -1,5660 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- E X P _ A T T R -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2009, 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. -- --- -- --- You should have received a copy of the GNU General Public License along -- --- with this program; see file COPYING3. If not see -- --- <http://www.gnu.org/licenses/>. -- --- -- --- 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_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 -- - ----------------------- - - procedure Compile_Stream_Body_In_Scope - (N : Node_Id; - Decl : Node_Id; - Arr : Entity_Id; - Check : Boolean); - -- The body for a stream subprogram may be generated outside of the scope - -- of the type. If the type is fully private, it may depend on the full - -- view of other types (e.g. indices) that are currently private as well. - -- We install the declarations of the package in which the type is declared - -- before compiling the body in what is its proper environment. The Check - -- parameter indicates if checks are to be suppressed for the stream body. - -- We suppress checks for array/record reads, since the rule is that these - -- are like assignments, out of range values due to uninitialized storage, - -- or other invalid values do NOT cause a Constraint_Error to be raised. - - procedure Expand_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. - - 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 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. - - ---------------------------------- - -- 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; - 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_In (Par, N_Procedure_Call_Statement, N_Function_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; - - Agg := - Make_Aggregate (Loc, - Expressions => - New_List ( - Obj_Ref, - Unchecked_Convert_To (Acc, - Make_Attribute_Reference (Loc, - Prefix => Sub, - Attribute_Name => Name_Address)))); - - Rewrite (N, Agg); - - Analyze_And_Resolve (N, 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_Defining_Identifier - (Loc, New_Internal_Name ('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; - - -- 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_05 - 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. - - if Is_Protected_Self_Reference (Pref) then - Rewrite (Pref, Concurrent_Ref (Pref)); - Analyze (Pref); - end if; - - -- Remaining processing depends on specific attribute - - case Id is - - ------------ - -- 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); - - -- 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 (but not an anonymous access type), 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 - 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 - - if Btyp_DDT /= Etype (Ref_Object) then - 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. - - if Obj_DDT /= Btyp_DDT - 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 VM_Target = No_VM - 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 - - -- 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_uAlignment), Loc), - Parameter_Associations => New_List (Pref)); - - if Typ /= Standard_Integer then - - -- The context is a specific integer type with which the - -- original attribute was compatible. The function has a - -- specific type as well, so to preserve the compatibility - -- we must convert explicitly. - - New_Node := Convert_To (Typ, New_Node); - end if; - - Rewrite (N, New_Node); - Analyze_And_Resolve (N, Typ); - return; - - -- For 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_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 - -- the unsigned constant created in the main program by the binder. - - -- A special exception occurs for Standard, where the string - -- returned is a copy of the library string in gnatvsn.ads. - - when Attribute_Body_Version | Attribute_Version => Version : declare - E : constant Entity_Id := - Make_Defining_Identifier (Loc, New_Internal_Name ('V')); - Pent : Entity_Id; - 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_05 - 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 Has_Constrained_Partial_View - (Base_Type (Etype (Obj))))); - 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_05 - and then Is_Aliased_View (Pref)) - or else (Ada_Version >= Ada_05 - 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 - Res := Is_Constrained (Underlying_Type (Etype (Ent))); - 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 AI-363). - - else - Rewrite (N, - New_Reference_To ( - Boolean_Literals ( - not Is_Variable (Pref) - or else - (Nkind (Pref) = N_Explicit_Dereference - and then - not Has_Constrained_Partial_View (Base_Type (Ptyp))) - or else Is_Constrained (Underlying_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; - - --------------- - -- Elab_Body -- - --------------- - - -- This processing is shared by Elab_Spec - - -- What we do is to insert the following declarations - - -- procedure tnn; - -- pragma Import (C, enn, "name___elabb/s"); - - -- and then the Elab_Body/Spec attribute is replaced by a reference - -- to this defining identifier. - - when Attribute_Elab_Body | - Attribute_Elab_Spec => - - Elab_Body : declare - Ent : constant Entity_Id := - Make_Defining_Identifier (Loc, - New_Internal_Name ('E')); - Str : String_Id; - Lang : Node_Id; - - procedure Make_Elab_String (Nod : Node_Id); - -- Given Nod, an identifier, or a selected component, put the - -- image into the current string literal, with double underline - -- between components. - - ---------------------- - -- 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; - - ---------------- - -- 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, - New_Occurrence_Of (Elaboration_Entity (Ent), Loc)); - else - Rewrite (N, New_Occurrence_Of (Standard_True, Loc)); - end if; - end Elaborated; - - -------------- - -- Enum_Rep -- - -------------- - - when Attribute_Enum_Rep => Enum_Rep : - begin - -- X'Enum_Rep (Y) expands to - - -- target-type (Y) - - -- This is simply a direct conversion from the enumeration type to - -- the target integer type, which is treated by 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 : declare - CE : constant Entity_Id := Entity (Selector_Name (Pref)); - - begin - if Known_Static_Component_Bit_Offset (CE) then - Rewrite (N, - Make_Integer_Literal (Loc, - Component_Bit_Offset (CE) mod System_Storage_Unit)); - - Analyze_And_Resolve (N, Typ); - - else - Apply_Universal_Integer_Attribute_Checks (N); - end if; - end First_Bit; - - ----------------- - -- Fixed_Value -- - ----------------- - - -- We transform: - - -- fixtype'Fixed_Value (integer-value) - - -- into - - -- fixtype(integer-value) - - -- We do all the required analysis of the conversion here, because we do - -- not want this to go through the fixed-point conversion circuits. Note - -- that 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_05 - 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; - - 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). - - Dnn := - Make_Defining_Identifier (Loc, - Chars => New_Internal_Name ('D')); - - Decl := - Make_Object_Declaration (Loc, - Defining_Identifier => Dnn, - Object_Definition => - New_Occurrence_Of (RTE (RE_Tag), Loc), - Expression => - Make_Function_Call (Loc, - Name => - New_Occurrence_Of (RTE (RE_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)))); - - 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_Record_Or_Elementary_Input_Function - (Loc, Base_Type (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 : declare - CE : constant Entity_Id := Entity (Selector_Name (Pref)); - - begin - if Known_Static_Component_Bit_Offset (CE) - and then Known_Static_Esize (CE) - then - Rewrite (N, - Make_Integer_Literal (Loc, - Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit) - + Esize (CE) - 1)); - - Analyze_And_Resolve (N, Typ); - - else - Apply_Universal_Integer_Attribute_Checks (N); - end if; - end Last_Bit; - - ------------------ - -- Leading_Part -- - ------------------ - - -- Transforms 'Leading_Part into a call to the floating-point attribute - -- function Leading_Part in Fat_xxx (where xxx is the root type) - - -- Note: strictly, we should 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 => 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; - - ------------- - -- 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; - - -------------------- - -- 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 conditional 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_Conditional_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_Defining_Identifier (Loc, - Chars => New_Internal_Name ('T')); - Subp : Node_Id; - Asn_Stm : Node_Id; - - begin - -- 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 assignment at the start of the declarations - - Asn_Stm := - Make_Object_Declaration (Loc, - Defining_Identifier => Tnn, - Constant_Present => True, - Object_Definition => New_Occurrence_Of (Etype (N), Loc), - Expression => Pref); - - 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; - - Rewrite (N, New_Occurrence_Of (Tnn, Loc)); - end Old; - - ------------ - -- 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_05 - and then VM_Target = No_VM - 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 : - declare - CE : constant Entity_Id := Entity (Selector_Name (Pref)); - - begin - if Present (Component_Clause (CE)) then - Rewrite (N, - Make_Integer_Literal (Loc, - Intval => Component_Bit_Offset (CE) / System_Storage_Unit)); - Analyze_And_Resolve (N, Typ); - - else - Apply_Universal_Integer_Attribute_Checks (N); - end if; - end Position; - - ---------- - -- Pred -- - ---------- - - -- 1. Deal with enumeration types with holes - -- 2. For floating-point, generate call to attribute function - -- 3. For other cases, deal with constraint checking - - when Attribute_Pred => Pred : - declare - 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 range checking is enabled, we must generate - -- a check if overflow checking is enabled. - - elsif not Overflow_Checks_Suppressed (Ptyp) then - Expand_Pred_Succ (N); - end if; - end Pred; - - -------------- - -- 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, Base_Type (U_Type), Decl, Pname); - else - Build_Record_Read_Procedure - (Loc, Base_Type (U_Type), Decl, Pname); - end if; - - -- Suppress checks, uninitialized or otherwise invalid - -- data does not cause constraint errors to be raised for - -- a complete record read. - - Insert_Action (N, Decl, All_Checks); - end if; - end if; - - Rewrite_Stream_Proc_Call (Pname); - end Read; - - --------------- - -- Remainder -- - --------------- - - -- Transforms 'Remainder into a call to the floating-point attribute - -- function Remainder in Fat_xxx (where xxx is the root type) - - when Attribute_Remainder => - Expand_Fpt_Attribute_RR (N); - - ------------ - -- 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); - - ------------- - -- Scaling -- - ------------- - - -- Transforms 'Scaling into a call to the floating-point attribute - -- function Scaling in Fat_xxx (where xxx is the root type) - - when Attribute_Scaling => - Expand_Fpt_Attribute_RI (N); - - ---------- - -- Size -- - ---------- - - when Attribute_Size | - Attribute_Object_Size | - Attribute_Value_Size | - Attribute_VADS_Size => Size : - - declare - 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) 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 : begin - - -- Access type case, always go to the root type - - -- The case of access types results in a value of zero for the case - -- where no storage size attribute clause has been given. If a - -- storage size has been given, then the attribute is converted - -- to a reference to the variable used to hold this value. - - if Is_Access_Type (Ptyp) then - if Present (Storage_Size_Variable (Root_Type (Ptyp))) then - Rewrite (N, - Make_Attribute_Reference (Loc, - Prefix => New_Reference_To (Typ, Loc), - Attribute_Name => Name_Max, - Expressions => New_List ( - Make_Integer_Literal (Loc, 0), - Convert_To (Typ, - New_Reference_To - (Storage_Size_Variable (Root_Type (Ptyp)), Loc))))); - - elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then - Rewrite (N, - OK_Convert_To (Typ, - Make_Function_Call (Loc, - Name => - New_Reference_To - (Find_Prim_Op - (Etype (Associated_Storage_Pool (Root_Type (Ptyp))), - Attribute_Name (N)), - Loc), - - Parameter_Associations => New_List ( - New_Reference_To - (Associated_Storage_Pool (Root_Type (Ptyp)), Loc))))); - - else - Rewrite (N, Make_Integer_Literal (Loc, 0)); - end if; - - Analyze_And_Resolve (N, Typ); - - -- 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 => Stream_Size : declare - Size : Int; - - begin - -- If we have a Stream_Size clause for this type use it, otherwise - -- the Stream_Size if the size of the type. - - if Has_Stream_Size_Clause (Ptyp) then - Size := - UI_To_Int - (Static_Integer (Expression (Stream_Size_Clause (Ptyp)))); - else - Size := UI_To_Int (Esize (Ptyp)); - end if; - - Rewrite (N, Make_Integer_Literal (Loc, Intval => Size)); - Analyze_And_Resolve (N, Typ); - end Stream_Size; - - ---------- - -- Succ -- - ---------- - - -- 1. Deal with enumeration types with holes - -- 2. For floating-point, generate call to attribute function - -- 3. For other cases, deal with constraint checking - - when Attribute_Succ => Succ : - declare - 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 range checking is enabled, we must generate - -- a check if overflow checking is enabled. - - elsif not Overflow_Checks_Suppressed (Ptyp) then - Expand_Pred_Succ (N); - end if; - end Succ; - - --------- - -- Tag -- - --------- - - -- Transforms X'Tag into a direct reference to the tag of X - - when Attribute_Tag => Tag : - declare - Ttyp : Entity_Id; - Prefix_Is_Type : Boolean; - - begin - if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then - Ttyp := Entity (Pref); - Prefix_Is_Type := True; - else - Ttyp := Ptyp; - Prefix_Is_Type := False; - end if; - - if Is_Class_Wide_Type (Ttyp) then - Ttyp := Root_Type (Ttyp); - end if; - - Ttyp := Underlying_Type (Ttyp); - - if Prefix_Is_Type then - - -- For VMs we leave the type attribute unexpanded because - -- there's not a dispatching table to reference. - - if VM_Target = No_VM 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 VM_Target = No_VM 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_05 - 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) into unchecked conversion - -- from (integral) type of X to type address. - - when Attribute_To_Address => - Rewrite (N, - Unchecked_Convert_To (RTE (RE_Address), - Relocate_Node (First (Exprs)))); - Analyze_And_Resolve (N, RTE (RE_Address)); - - ------------ - -- 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 - (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_Defining_Identifier (Loc, New_Internal_Name ('T')); - - begin - Insert_Action (N, - Make_Object_Declaration (Loc, - Defining_Identifier => Ent, - Aliased_Present => True, - Object_Definition => - New_Occurrence_Of (RTE (RE_Address), Loc))); - - -- Construct name __gnat_xxx__SDP, where xxx is the unit name - -- in normal external form. - - Get_External_Unit_Name_String (Get_Unit_Name (Pref)); - Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len); - Name_Len := Name_Len + 7; - Name_Buffer (1 .. 7) := "__gnat_"; - Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP"; - Name_Len := Name_Len + 5; - - Set_Is_Imported (Ent); - Set_Interface_Name (Ent, - Make_String_Literal (Loc, - Strval => String_From_Name_Buffer)); - - -- 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; - - --------------- - -- 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); - 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) >= Btyp!(Ptyp'First) - -- and then - -- Btyp!(Pref) <= Btyp!(Ptyp'Last) - - --------------------- - -- Make_Range_Test -- - --------------------- - - function Make_Range_Test return Node_Id is - begin - return - Make_And_Then (Loc, - Left_Opnd => - Make_Op_Ge (Loc, - Left_Opnd => - Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)), - - Right_Opnd => - Unchecked_Convert_To (Btyp, - Make_Attribute_Reference (Loc, - Prefix => New_Occurrence_Of (Ptyp, Loc), - Attribute_Name => Name_First))), - - Right_Opnd => - Make_Op_Le (Loc, - Left_Opnd => - Unchecked_Convert_To (Btyp, - Duplicate_Subexpr_No_Checks (Pref)), - - Right_Opnd => - Unchecked_Convert_To (Btyp, - Make_Attribute_Reference (Loc, - Prefix => New_Occurrence_Of (Ptyp, Loc), - Attribute_Name => Name_Last)))); - end Make_Range_Test; - - -- Start of processing for Attribute_Valid - - begin - -- 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; - - -- 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 - -- For vax fpt types, call appropriate routine in special vax - -- floating point unit. We do not have to worry about loads in - -- this case, since these types have no signalling NaN's. - - if Vax_Float (Btyp) then - Expand_Vax_Valid (N); - - -- The AAMP back end handles Valid for floating-point types - - elsif Is_AAMP_Float (Btyp) then - Analyze_And_Resolve (Pref, Ptyp); - Set_Etype (N, Standard_Boolean); - Set_Analyzed (N); - - -- Non VAX float case - - else - 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 if; - - -- 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 (Base_Type (Ptyp))) - then - Tst := - Make_Op_Ge (Loc, - Left_Opnd => - Make_Function_Call (Loc, - Name => - New_Reference_To - (TSS (Base_Type (Ptyp), 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; - - Analyze_And_Resolve (N, Standard_Boolean); - Validity_Checks_On := Save_Validity_Checks_On; - end Valid; - - ----------- - -- Value -- - ----------- - - -- Value attribute is handled in separate unti Exp_Imgv - - when Attribute_Value => - Exp_Imgv.Expand_Value_Attribute (N); - - ----------------- - -- Value_Size -- - ----------------- - - -- The processing for Value_Size shares the processing for Size - - ------------- - -- Version -- - ------------- - - -- The processing for Version shares the processing for Body_Version - - ---------------- - -- Wide_Image -- - ---------------- - - -- 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, Base_Type (U_Type), Decl, Pname); - else - Build_Record_Write_Procedure - (Loc, Base_Type (U_Type), Decl, Pname); - end if; - - Insert_Action (N, Decl); - end if; - end if; - - -- If we fall through, Pname is the procedure to be called - - Rewrite_Stream_Proc_Call (Pname); - end Write; - - -- Component_Size is handled by 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 => - 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_Bit | - Attribute_Max_Size_In_Storage_Elements - => - Apply_Universal_Integer_Attribute_Checks (N); - - -- The following attributes should not appear at this stage, since they - -- have already been handled by the analyzer (and properly rewritten - -- with corresponding values or entities to represent the right values) - - when Attribute_Abort_Signal | - Attribute_Address_Size | - Attribute_Base | - Attribute_Class | - Attribute_Default_Bit_Order | - Attribute_Delta | - Attribute_Denorm | - Attribute_Digits | - Attribute_Emax | - Attribute_Enabled | - Attribute_Epsilon | - Attribute_Fast_Math | - Attribute_Has_Access_Values | - Attribute_Has_Discriminants | - Attribute_Has_Tagged_Values | - Attribute_Large | - 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_Target_Name | - Attribute_Type_Class | - 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; - - 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. - - procedure Expand_Pred_Succ (N : Node_Id) is - Loc : constant Source_Ptr := Sloc (N); - Cnam : Name_Id; - - begin - if Attribute_Name (N) = Name_Pred then - Cnam := Name_First; - else - Cnam := Name_Last; - end if; - - Insert_Action (N, - Make_Raise_Constraint_Error (Loc, - Condition => - Make_Op_Eq (Loc, - Left_Opnd => - Duplicate_Subexpr_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 Expand_Pred_Succ; - - ------------------- - -- 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_Float 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); - - 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 making dependences on files not - -- supported in the AAMP library (such as s-fileio.adb). - - 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 then - return RTE (RE_String_Input); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_String_Output); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_String_Read); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_String_Write); - end if; - - else - if Nam = TSS_Stream_Input then - return RTE (RE_String_Input_Blk_IO); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_String_Output_Blk_IO); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_String_Read_Blk_IO); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_String_Write_Blk_IO); - 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 then - return RTE (RE_Wide_String_Input); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_Wide_String_Output); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_Wide_String_Read); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_Wide_String_Write); - end if; - - else - if Nam = TSS_Stream_Input then - return RTE (RE_Wide_String_Input_Blk_IO); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_Wide_String_Output_Blk_IO); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_Wide_String_Read_Blk_IO); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_Wide_String_Write_Blk_IO); - 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 then - return RTE (RE_Wide_Wide_String_Input); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_Wide_Wide_String_Output); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_Wide_Wide_String_Read); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_Wide_Wide_String_Write); - end if; - - else - if Nam = TSS_Stream_Input then - return RTE (RE_Wide_Wide_String_Input_Blk_IO); - - elsif Nam = TSS_Stream_Output then - return RTE (RE_Wide_Wide_String_Output_Blk_IO); - - elsif Nam = TSS_Stream_Read then - return RTE (RE_Wide_Wide_String_Read_Blk_IO); - - else pragma Assert (Nam = TSS_Stream_Write); - return RTE (RE_Wide_Wide_String_Write_Blk_IO); - 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; - - ----------------------- - -- 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; |