+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- F R E E Z E --
--- --
--- B o d y --
--- --
--- $Revision: 1.2.10.1 $
--- --
--- Copyright (C) 1992-2001, Free Software Foundation, Inc. --
--- --
--- GNAT is free software; you can redistribute it and/or modify it under --
--- terms of the GNU General Public License as published by the Free Soft- --
--- ware Foundation; either version 2, or (at your option) any later ver- --
--- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
--- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
--- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
--- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNAT; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- GNAT was originally developed by the GNAT team at New York University. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
-with Atree; use Atree;
-with Debug; use Debug;
-with Einfo; use Einfo;
-with Elists; use Elists;
-with Errout; use Errout;
-with Exp_Ch7; use Exp_Ch7;
-with Exp_Ch11; use Exp_Ch11;
-with Exp_Pakd; use Exp_Pakd;
-with Exp_Util; use Exp_Util;
-with Layout; use Layout;
-with Nlists; use Nlists;
-with Nmake; use Nmake;
-with Opt; use Opt;
-with Restrict; use Restrict;
-with Sem; use Sem;
-with Sem_Cat; use Sem_Cat;
-with Sem_Ch6; use Sem_Ch6;
-with Sem_Ch7; use Sem_Ch7;
-with Sem_Ch8; use Sem_Ch8;
-with Sem_Ch13; use Sem_Ch13;
-with Sem_Eval; use Sem_Eval;
-with Sem_Mech; use Sem_Mech;
-with Sem_Prag; use Sem_Prag;
-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 Targparm; use Targparm;
-with Tbuild; use Tbuild;
-with Ttypes; use Ttypes;
-with Uintp; use Uintp;
-with Urealp; use Urealp;
-
-package body Freeze is
-
- -----------------------
- -- Local Subprograms --
- -----------------------
-
- procedure Adjust_Esize_For_Alignment (Typ : Entity_Id);
- -- Typ is a type that is being frozen. If no size clause is given,
- -- but a default Esize has been computed, then this default Esize is
- -- adjusted up if necessary to be consistent with a given alignment,
- -- but never to a value greater than Long_Long_Integer'Size. This
- -- is used for all discrete types and for fixed-point types.
-
- procedure Build_And_Analyze_Renamed_Body
- (Decl : Node_Id;
- New_S : Entity_Id;
- After : in out Node_Id);
- -- Build body for a renaming declaration, insert in tree and analyze.
-
- procedure Check_Strict_Alignment (E : Entity_Id);
- -- E is a base type. If E is tagged or has a component that is aliased
- -- or tagged or contains something this is aliased or tagged, set
- -- Strict_Alignment.
-
- procedure Check_Unsigned_Type (E : Entity_Id);
- pragma Inline (Check_Unsigned_Type);
- -- If E is a fixed-point or discrete type, then all the necessary work
- -- to freeze it is completed except for possible setting of the flag
- -- Is_Unsigned_Type, which is done by this procedure. The call has no
- -- effect if the entity E is not a discrete or fixed-point type.
-
- procedure Freeze_And_Append
- (Ent : Entity_Id;
- Loc : Source_Ptr;
- Result : in out List_Id);
- -- Freezes Ent using Freeze_Entity, and appends the resulting list of
- -- nodes to Result, modifying Result from No_List if necessary.
-
- procedure Freeze_Enumeration_Type (Typ : Entity_Id);
- -- Freeze enumeration type. The Esize field is set as processing
- -- proceeds (i.e. set by default when the type is declared and then
- -- adjusted by rep clauses. What this procedure does is to make sure
- -- that if a foreign convention is specified, and no specific size
- -- is given, then the size must be at least Integer'Size.
-
- procedure Freeze_Static_Object (E : Entity_Id);
- -- If an object is frozen which has Is_Statically_Allocated set, then
- -- all referenced types must also be marked with this flag. This routine
- -- is in charge of meeting this requirement for the object entity E.
-
- procedure Freeze_Subprogram (E : Entity_Id);
- -- Perform freezing actions for a subprogram (create extra formals,
- -- and set proper default mechanism values). Note that this routine
- -- is not called for internal subprograms, for which neither of these
- -- actions is needed (or desirable, we do not want for example to have
- -- these extra formals present in initialization procedures, where they
- -- would serve no purpose). In this call E is either a subprogram or
- -- a subprogram type (i.e. an access to a subprogram).
-
- function Is_Fully_Defined (T : Entity_Id) return Boolean;
- -- true if T is not private, or has a full view.
-
- procedure Process_Default_Expressions
- (E : Entity_Id;
- After : in out Node_Id);
- -- This procedure is called for each subprogram to complete processing
- -- of default expressions at the point where all types are known to be
- -- frozen. The expressions must be analyzed in full, to make sure that
- -- all error processing is done (they have only been pre-analyzed). If
- -- the expression is not an entity or literal, its analysis may generate
- -- code which must not be executed. In that case we build a function
- -- body to hold that code. This wrapper function serves no other purpose
- -- (it used to be called to evaluate the default, but now the default is
- -- inlined at each point of call).
-
- procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id);
- -- Typ is a record or array type that is being frozen. This routine
- -- sets the default component alignment from the scope stack values
- -- if the alignment is otherwise not specified.
-
- procedure Check_Debug_Info_Needed (T : Entity_Id);
- -- As each entity is frozen, this routine is called to deal with the
- -- setting of Debug_Info_Needed for the entity. This flag is set if
- -- the entity comes from source, or if we are in Debug_Generated_Code
- -- mode or if the -gnatdV debug flag is set. However, it never sets
- -- the flag if Debug_Info_Off is set.
-
- procedure Set_Debug_Info_Needed (T : Entity_Id);
- -- Sets the Debug_Info_Needed flag on entity T if not already set, and
- -- also on any entities that are needed by T (for an object, the type
- -- of the object is needed, and for a type, the subsidiary types are
- -- needed -- see body for details). Never has any effect on T if the
- -- Debug_Info_Off flag is set.
-
- -------------------------------
- -- Adjust_Esize_For_Alignment --
- -------------------------------
-
- procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is
- Align : Uint;
-
- begin
- if Known_Esize (Typ) and then Known_Alignment (Typ) then
- Align := Alignment_In_Bits (Typ);
-
- if Align > Esize (Typ)
- and then Align <= Standard_Long_Long_Integer_Size
- then
- Set_Esize (Typ, Align);
- end if;
- end if;
- end Adjust_Esize_For_Alignment;
-
- ------------------------------------
- -- Build_And_Analyze_Renamed_Body --
- ------------------------------------
-
- procedure Build_And_Analyze_Renamed_Body
- (Decl : Node_Id;
- New_S : Entity_Id;
- After : in out Node_Id)
- is
- Body_Node : constant Node_Id := Build_Renamed_Body (Decl, New_S);
-
- begin
- Insert_After (After, Body_Node);
- Mark_Rewrite_Insertion (Body_Node);
- Analyze (Body_Node);
- After := Body_Node;
- end Build_And_Analyze_Renamed_Body;
-
- ------------------------
- -- Build_Renamed_Body --
- ------------------------
-
- function Build_Renamed_Body
- (Decl : Node_Id;
- New_S : Entity_Id)
- return Node_Id
- is
- Loc : constant Source_Ptr := Sloc (New_S);
- -- We use for the source location of the renamed body, the location
- -- of the spec entity. It might seem more natural to use the location
- -- of the renaming declaration itself, but that would be wrong, since
- -- then the body we create would look as though it was created far
- -- too late, and this could cause problems with elaboration order
- -- analysis, particularly in connection with instantiations.
-
- N : constant Node_Id := Unit_Declaration_Node (New_S);
- Nam : constant Node_Id := Name (N);
- Old_S : Entity_Id;
- Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
- Actuals : List_Id := No_List;
- Call_Node : Node_Id;
- Call_Name : Node_Id;
- Body_Node : Node_Id;
- Formal : Entity_Id;
- O_Formal : Entity_Id;
- Param_Spec : Node_Id;
-
- begin
- -- Determine the entity being renamed, which is the target of the
- -- call statement. If the name is an explicit dereference, this is
- -- a renaming of a subprogram type rather than a subprogram. The
- -- name itself is fully analyzed.
-
- if Nkind (Nam) = N_Selected_Component then
- Old_S := Entity (Selector_Name (Nam));
-
- elsif Nkind (Nam) = N_Explicit_Dereference then
- Old_S := Etype (Nam);
-
- elsif Nkind (Nam) = N_Indexed_Component then
-
- if Is_Entity_Name (Prefix (Nam)) then
- Old_S := Entity (Prefix (Nam));
- else
- Old_S := Entity (Selector_Name (Prefix (Nam)));
- end if;
-
- elsif Nkind (Nam) = N_Character_Literal then
- Old_S := Etype (New_S);
-
- else
- Old_S := Entity (Nam);
- end if;
-
- if Is_Entity_Name (Nam) then
- Call_Name := New_Reference_To (Old_S, Loc);
- else
- Call_Name := New_Copy (Name (N));
-
- -- The original name may have been overloaded, but
- -- is fully resolved now.
-
- Set_Is_Overloaded (Call_Name, False);
- end if;
-
- -- For simple renamings, subsequent calls can be expanded directly
- -- as called to the renamed entity. The body must be generated in
- -- any case for calls they may appear elsewhere.
-
- if (Ekind (Old_S) = E_Function
- or else Ekind (Old_S) = E_Procedure)
- and then Nkind (Decl) = N_Subprogram_Declaration
- then
- Set_Body_To_Inline (Decl, Old_S);
- end if;
-
- -- The body generated for this renaming is an internal artifact, and
- -- does not constitute a freeze point for the called entity.
-
- Set_Must_Not_Freeze (Call_Name);
-
- Formal := First_Formal (Defining_Entity (Decl));
-
- if Present (Formal) then
- Actuals := New_List;
-
- while Present (Formal) loop
- Append (New_Reference_To (Formal, Loc), Actuals);
- Next_Formal (Formal);
- end loop;
- end if;
-
- -- If the renamed entity is an entry, inherit its profile. For
- -- other renamings as bodies, both profiles must be subtype
- -- conformant, so it is not necessary to replace the profile given
- -- in the declaration. However, default values that are aggregates
- -- are rewritten when partially analyzed, so we recover the original
- -- aggregate to insure that subsequent conformity checking works.
-
- Formal := First_Formal (Defining_Entity (Decl));
-
- if Present (Formal) then
- O_Formal := First_Formal (Old_S);
- Param_Spec := First (Parameter_Specifications (Spec));
-
- while Present (Formal) loop
- if Is_Entry (Old_S) then
-
- if Nkind (Parameter_Type (Param_Spec)) /=
- N_Access_Definition
- then
- Set_Etype (Formal, Etype (O_Formal));
- Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
- end if;
-
- elsif Nkind (Default_Value (O_Formal)) = N_Aggregate then
- Set_Expression (Param_Spec,
- New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
- end if;
-
- Next_Formal (Formal);
- Next_Formal (O_Formal);
- Next (Param_Spec);
- end loop;
- end if;
-
- -- If the renamed entity is a function, the generated body contains a
- -- return statement. Otherwise, build a procedure call. If the entity is
- -- an entry, subsequent analysis of the call will transform it into the
- -- proper entry or protected operation call. If the renamed entity is
- -- a character literal, return it directly.
-
- if Ekind (Old_S) = E_Function
- or else Ekind (Old_S) = E_Operator
- or else (Ekind (Old_S) = E_Subprogram_Type
- and then Etype (Old_S) /= Standard_Void_Type)
- then
- Call_Node :=
- Make_Return_Statement (Loc,
- Expression =>
- Make_Function_Call (Loc,
- Name => Call_Name,
- Parameter_Associations => Actuals));
-
- elsif Ekind (Old_S) = E_Enumeration_Literal then
- Call_Node :=
- Make_Return_Statement (Loc,
- Expression => New_Occurrence_Of (Old_S, Loc));
-
- elsif Nkind (Nam) = N_Character_Literal then
- Call_Node :=
- Make_Return_Statement (Loc,
- Expression => Call_Name);
-
- else
- Call_Node :=
- Make_Procedure_Call_Statement (Loc,
- Name => Call_Name,
- Parameter_Associations => Actuals);
- end if;
-
- -- Create entities for subprogram body and formals.
-
- Set_Defining_Unit_Name (Spec,
- Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
-
- Param_Spec := First (Parameter_Specifications (Spec));
-
- while Present (Param_Spec) loop
- Set_Defining_Identifier (Param_Spec,
- Make_Defining_Identifier (Loc,
- Chars => Chars (Defining_Identifier (Param_Spec))));
- Next (Param_Spec);
- end loop;
-
- Body_Node :=
- Make_Subprogram_Body (Loc,
- Specification => Spec,
- Declarations => New_List,
- Handled_Statement_Sequence =>
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => New_List (Call_Node)));
-
- if Nkind (Decl) /= N_Subprogram_Declaration then
- Rewrite (N,
- Make_Subprogram_Declaration (Loc,
- Specification => Specification (N)));
- end if;
-
- -- Link the body to the entity whose declaration it completes. If
- -- the body is analyzed when the renamed entity is frozen, it may be
- -- necessary to restore the proper scope (see package Exp_Ch13).
-
- if Nkind (N) = N_Subprogram_Renaming_Declaration
- and then Present (Corresponding_Spec (N))
- then
- Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
- else
- Set_Corresponding_Spec (Body_Node, New_S);
- end if;
-
- return Body_Node;
- end Build_Renamed_Body;
-
- -----------------------------
- -- Check_Compile_Time_Size --
- -----------------------------
-
- procedure Check_Compile_Time_Size (T : Entity_Id) is
-
- procedure Set_Small_Size (S : Uint);
- -- Sets the compile time known size (32 bits or less) in the Esize
- -- field, checking for a size clause that was given which attempts
- -- to give a smaller size.
-
- function Size_Known (T : Entity_Id) return Boolean;
- -- Recursive function that does all the work.
- -- Is this right??? isn't recursive case already handled???
- -- certainly yes for normal call, but what about bogus sem_res call???
-
- function Static_Discriminated_Components (T : Entity_Id) return Boolean;
- -- If T is a constrained subtype, its size is not known if any of its
- -- discriminant constraints is not static and it is not a null record.
- -- The test is conservative and doesn't check that the components are
- -- in fact constrained by non-static discriminant values. Could be made
- -- more precise ???
-
- --------------------
- -- Set_Small_Size --
- --------------------
-
- procedure Set_Small_Size (S : Uint) is
- begin
- if S > 32 then
- return;
-
- elsif Has_Size_Clause (T) then
- if RM_Size (T) < S then
- Error_Msg_Uint_1 := S;
- Error_Msg_NE
- ("size for & is too small, minimum is ^",
- Size_Clause (T), T);
-
- elsif Unknown_Esize (T) then
- Set_Esize (T, S);
- end if;
-
- -- Set sizes if not set already
-
- else
- if Unknown_Esize (T) then
- Set_Esize (T, S);
- end if;
-
- if Unknown_RM_Size (T) then
- Set_RM_Size (T, S);
- end if;
- end if;
- end Set_Small_Size;
-
- ----------------
- -- Size_Known --
- ----------------
-
- function Size_Known (T : Entity_Id) return Boolean is
- Index : Entity_Id;
- Comp : Entity_Id;
- Ctyp : Entity_Id;
- Low : Node_Id;
- High : Node_Id;
-
- begin
- if Size_Known_At_Compile_Time (T) then
- return True;
-
- elsif Error_Posted (T) then
- return False;
-
- elsif Is_Scalar_Type (T)
- or else Is_Task_Type (T)
- then
- return not Is_Generic_Type (T);
-
- elsif Is_Array_Type (T) then
-
- if Ekind (T) = E_String_Literal_Subtype then
- Set_Small_Size (Component_Size (T) * String_Literal_Length (T));
- return True;
-
- elsif not Is_Constrained (T) then
- return False;
-
- elsif not Size_Known (Component_Type (T)) then
- return False;
- end if;
-
- -- Check for all indexes static, and also compute possible
- -- size (in case it is less than 32 and may be packable).
-
- declare
- Esiz : Uint := Component_Size (T);
- Dim : Uint;
-
- begin
- Index := First_Index (T);
-
- while Present (Index) loop
- if Nkind (Index) = N_Range then
- Get_Index_Bounds (Index, Low, High);
-
- elsif Error_Posted (Scalar_Range (Etype (Index))) then
- return False;
-
- else
- Low := Type_Low_Bound (Etype (Index));
- High := Type_High_Bound (Etype (Index));
- end if;
-
- if not Compile_Time_Known_Value (Low)
- or else not Compile_Time_Known_Value (High)
- or else Etype (Index) = Any_Type
- then
- return False;
-
- else
- Dim := Expr_Value (High) - Expr_Value (Low) + 1;
-
- if Dim >= 0 then
- Esiz := Esiz * Dim;
- else
- Esiz := Uint_0;
- end if;
- end if;
-
- Next_Index (Index);
- end loop;
-
- Set_Small_Size (Esiz);
- return True;
- end;
-
- elsif Is_Access_Type (T) then
- return True;
-
- elsif Is_Private_Type (T)
- and then not Is_Generic_Type (T)
- and then Present (Underlying_Type (T))
- then
- return Size_Known (Underlying_Type (T));
-
- elsif Is_Record_Type (T) then
- if Is_Class_Wide_Type (T) then
- return False;
-
- elsif T /= Base_Type (T) then
- return Size_Known_At_Compile_Time (Base_Type (T))
- and then Static_Discriminated_Components (T);
-
- else
- declare
- Packed_Size_Known : Boolean := Is_Packed (T);
- Packed_Size : Uint := Uint_0;
-
- begin
- -- Test for variant part present
-
- if Has_Discriminants (T)
- and then Present (Parent (T))
- and then Nkind (Parent (T)) = N_Full_Type_Declaration
- and then Nkind (Type_Definition (Parent (T))) =
- N_Record_Definition
- and then not Null_Present (Type_Definition (Parent (T)))
- and then Present (Variant_Part
- (Component_List (Type_Definition (Parent (T)))))
- then
- -- If variant part is present, and type is unconstrained,
- -- then we must have defaulted discriminants, or a size
- -- clause must be present for the type, or else the size
- -- is definitely not known at compile time.
-
- if not Is_Constrained (T)
- and then
- No (Discriminant_Default_Value
- (First_Discriminant (T)))
- and then Unknown_Esize (T)
- then
- return False;
- else
- -- We do not know the packed size, it is too much
- -- trouble to figure it out.
-
- Packed_Size_Known := False;
- end if;
- end if;
-
- Comp := First_Entity (T);
-
- while Present (Comp) loop
- if Ekind (Comp) = E_Component
- or else
- Ekind (Comp) = E_Discriminant
- then
- Ctyp := Etype (Comp);
-
- if Present (Component_Clause (Comp)) then
- Packed_Size_Known := False;
- end if;
-
- if not Size_Known (Ctyp) then
- return False;
-
- elsif Packed_Size_Known then
-
- -- If RM_Size is known and static, then we can
- -- keep accumulating the packed size.
-
- if Known_Static_RM_Size (Ctyp) then
-
- -- A little glitch, to be removed sometime ???
- -- gigi does not understand zero sizes yet.
-
- if RM_Size (Ctyp) = Uint_0 then
- Packed_Size_Known := False;
- end if;
-
- Packed_Size :=
- Packed_Size + RM_Size (Ctyp);
-
- -- If we have a field whose RM_Size is not known
- -- then we can't figure out the packed size here.
-
- else
- Packed_Size_Known := False;
- end if;
- end if;
- end if;
-
- Next_Entity (Comp);
- end loop;
-
- if Packed_Size_Known then
- Set_Small_Size (Packed_Size);
- end if;
-
- return True;
- end;
- end if;
-
- else
- return False;
- end if;
- end Size_Known;
-
- -------------------------------------
- -- Static_Discriminated_Components --
- -------------------------------------
-
- function Static_Discriminated_Components
- (T : Entity_Id)
- return Boolean
- is
- Constraint : Elmt_Id;
-
- begin
- if Has_Discriminants (T)
- and then Present (Discriminant_Constraint (T))
- and then Present (First_Component (T))
- then
- Constraint := First_Elmt (Discriminant_Constraint (T));
-
- while Present (Constraint) loop
- if not Compile_Time_Known_Value (Node (Constraint)) then
- return False;
- end if;
-
- Next_Elmt (Constraint);
- end loop;
- end if;
-
- return True;
- end Static_Discriminated_Components;
-
- -- Start of processing for Check_Compile_Time_Size
-
- begin
- Set_Size_Known_At_Compile_Time (T, Size_Known (T));
- end Check_Compile_Time_Size;
-
- -----------------------------
- -- Check_Debug_Info_Needed --
- -----------------------------
-
- procedure Check_Debug_Info_Needed (T : Entity_Id) is
- begin
- if Needs_Debug_Info (T) or else Debug_Info_Off (T) then
- return;
-
- elsif Comes_From_Source (T)
- or else Debug_Generated_Code
- or else Debug_Flag_VV
- then
- Set_Debug_Info_Needed (T);
- end if;
- end Check_Debug_Info_Needed;
-
- ----------------------------
- -- Check_Strict_Alignment --
- ----------------------------
-
- procedure Check_Strict_Alignment (E : Entity_Id) is
- Comp : Entity_Id;
-
- begin
- if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
- Set_Strict_Alignment (E);
-
- elsif Is_Array_Type (E) then
- Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
-
- elsif Is_Record_Type (E) then
- if Is_Limited_Record (E) then
- Set_Strict_Alignment (E);
- return;
- end if;
-
- Comp := First_Component (E);
-
- while Present (Comp) loop
- if not Is_Type (Comp)
- and then (Strict_Alignment (Etype (Comp))
- or else Is_Aliased (Comp))
- then
- Set_Strict_Alignment (E);
- return;
- end if;
-
- Next_Component (Comp);
- end loop;
- end if;
- end Check_Strict_Alignment;
-
- -------------------------
- -- Check_Unsigned_Type --
- -------------------------
-
- procedure Check_Unsigned_Type (E : Entity_Id) is
- Ancestor : Entity_Id;
- Lo_Bound : Node_Id;
- Btyp : Entity_Id;
-
- begin
- if not Is_Discrete_Or_Fixed_Point_Type (E) then
- return;
- end if;
-
- -- Do not attempt to analyze case where range was in error
-
- if Error_Posted (Scalar_Range (E)) then
- return;
- end if;
-
- -- The situation that is non trivial is something like
-
- -- subtype x1 is integer range -10 .. +10;
- -- subtype x2 is x1 range 0 .. V1;
- -- subtype x3 is x2 range V2 .. V3;
- -- subtype x4 is x3 range V4 .. V5;
-
- -- where Vn are variables. Here the base type is signed, but we still
- -- know that x4 is unsigned because of the lower bound of x2.
-
- -- The only way to deal with this is to look up the ancestor chain
-
- Ancestor := E;
- loop
- if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
- return;
- end if;
-
- Lo_Bound := Type_Low_Bound (Ancestor);
-
- if Compile_Time_Known_Value (Lo_Bound) then
-
- if Expr_Rep_Value (Lo_Bound) >= 0 then
- Set_Is_Unsigned_Type (E, True);
- end if;
-
- return;
-
- else
- Ancestor := Ancestor_Subtype (Ancestor);
-
- -- If no ancestor had a static lower bound, go to base type
-
- if No (Ancestor) then
-
- -- Note: the reason we still check for a compile time known
- -- value for the base type is that at least in the case of
- -- generic formals, we can have bounds that fail this test,
- -- and there may be other cases in error situations.
-
- Btyp := Base_Type (E);
-
- if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
- return;
- end if;
-
- Lo_Bound := Type_Low_Bound (Base_Type (E));
-
- if Compile_Time_Known_Value (Lo_Bound)
- and then Expr_Rep_Value (Lo_Bound) >= 0
- then
- Set_Is_Unsigned_Type (E, True);
- end if;
-
- return;
-
- end if;
- end if;
- end loop;
- end Check_Unsigned_Type;
-
- ----------------
- -- Freeze_All --
- ----------------
-
- -- Note: the easy coding for this procedure would be to just build a
- -- single list of freeze nodes and then insert them and analyze them
- -- all at once. This won't work, because the analysis of earlier freeze
- -- nodes may recursively freeze types which would otherwise appear later
- -- on in the freeze list. So we must analyze and expand the freeze nodes
- -- as they are generated.
-
- procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
- Loc : constant Source_Ptr := Sloc (After);
- E : Entity_Id;
- Decl : Node_Id;
-
- procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
- -- This is the internal recursive routine that does freezing of
- -- entities (but NOT the analysis of default expressions, which
- -- should not be recursive, we don't want to analyze those till
- -- we are sure that ALL the types are frozen).
-
- procedure Freeze_All_Ent
- (From : Entity_Id;
- After : in out Node_Id)
- is
- E : Entity_Id;
- Flist : List_Id;
- Lastn : Node_Id;
-
- procedure Process_Flist;
- -- If freeze nodes are present, insert and analyze, and reset
- -- cursor for next insertion.
-
- procedure Process_Flist is
- begin
- if Is_Non_Empty_List (Flist) then
- Lastn := Next (After);
- Insert_List_After_And_Analyze (After, Flist);
-
- if Present (Lastn) then
- After := Prev (Lastn);
- else
- After := Last (List_Containing (After));
- end if;
- end if;
- end Process_Flist;
-
- begin
- E := From;
- while Present (E) loop
-
- -- If the entity is an inner package which is not a package
- -- renaming, then its entities must be frozen at this point.
- -- Note that such entities do NOT get frozen at the end of
- -- the nested package itself (only library packages freeze).
-
- -- Same is true for task declarations, where anonymous records
- -- created for entry parameters must be frozen.
-
- if Ekind (E) = E_Package
- and then No (Renamed_Object (E))
- and then not Is_Child_Unit (E)
- and then not Is_Frozen (E)
- then
- New_Scope (E);
- Install_Visible_Declarations (E);
- Install_Private_Declarations (E);
-
- Freeze_All (First_Entity (E), After);
-
- End_Package_Scope (E);
-
- elsif Ekind (E) in Task_Kind
- and then
- (Nkind (Parent (E)) = N_Task_Type_Declaration
- or else
- Nkind (Parent (E)) = N_Single_Task_Declaration)
- then
- New_Scope (E);
- Freeze_All (First_Entity (E), After);
- End_Scope;
-
- -- For a derived tagged type, we must ensure that all the
- -- primitive operations of the parent have been frozen, so
- -- that their addresses will be in the parent's dispatch table
- -- at the point it is inherited.
-
- elsif Ekind (E) = E_Record_Type
- and then Is_Tagged_Type (E)
- and then Is_Tagged_Type (Etype (E))
- and then Is_Derived_Type (E)
- then
- declare
- Prim_List : constant Elist_Id :=
- Primitive_Operations (Etype (E));
- Prim : Elmt_Id;
- Subp : Entity_Id;
-
- begin
- Prim := First_Elmt (Prim_List);
-
- while Present (Prim) loop
- Subp := Node (Prim);
-
- if Comes_From_Source (Subp)
- and then not Is_Frozen (Subp)
- then
- Flist := Freeze_Entity (Subp, Loc);
- Process_Flist;
- end if;
-
- Next_Elmt (Prim);
- end loop;
- end;
- end if;
-
- if not Is_Frozen (E) then
- Flist := Freeze_Entity (E, Loc);
- Process_Flist;
- end if;
-
- Next_Entity (E);
- end loop;
- end Freeze_All_Ent;
-
- -- Start of processing for Freeze_All
-
- begin
- Freeze_All_Ent (From, After);
-
- -- Now that all types are frozen, we can deal with default expressions
- -- that require us to build a default expression functions. This is the
- -- point at which such functions are constructed (after all types that
- -- might be used in such expressions have been frozen).
- -- We also add finalization chains to access types whose designated
- -- types are controlled. This is normally done when freezing the type,
- -- but this misses recursive type definitions where the later members
- -- of the recursion introduce controlled components (e.g. 5624-001).
-
- -- Loop through entities
-
- E := From;
- while Present (E) loop
-
- if Is_Subprogram (E) then
-
- if not Default_Expressions_Processed (E) then
- Process_Default_Expressions (E, After);
- end if;
-
- if not Has_Completion (E) then
- Decl := Unit_Declaration_Node (E);
-
- if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
- Build_And_Analyze_Renamed_Body (Decl, E, After);
-
- elsif Nkind (Decl) = N_Subprogram_Declaration
- and then Present (Corresponding_Body (Decl))
- and then
- Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
- = N_Subprogram_Renaming_Declaration
- then
- Build_And_Analyze_Renamed_Body
- (Decl, Corresponding_Body (Decl), After);
- end if;
- end if;
-
- elsif Ekind (E) in Task_Kind
- and then
- (Nkind (Parent (E)) = N_Task_Type_Declaration
- or else
- Nkind (Parent (E)) = N_Single_Task_Declaration)
- then
- declare
- Ent : Entity_Id;
-
- begin
- Ent := First_Entity (E);
-
- while Present (Ent) loop
-
- if Is_Entry (Ent)
- and then not Default_Expressions_Processed (Ent)
- then
- Process_Default_Expressions (Ent, After);
- end if;
-
- Next_Entity (Ent);
- end loop;
- end;
-
- elsif Is_Access_Type (E)
- and then Comes_From_Source (E)
- and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
- and then Controlled_Type (Designated_Type (E))
- and then No (Associated_Final_Chain (E))
- then
- Build_Final_List (Parent (E), E);
- end if;
-
- Next_Entity (E);
- end loop;
-
- end Freeze_All;
-
- -----------------------
- -- Freeze_And_Append --
- -----------------------
-
- procedure Freeze_And_Append
- (Ent : Entity_Id;
- Loc : Source_Ptr;
- Result : in out List_Id)
- is
- L : constant List_Id := Freeze_Entity (Ent, Loc);
-
- begin
- if Is_Non_Empty_List (L) then
- if Result = No_List then
- Result := L;
- else
- Append_List (L, Result);
- end if;
- end if;
- end Freeze_And_Append;
-
- -------------------
- -- Freeze_Before --
- -------------------
-
- procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
- Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
- F : Node_Id;
-
- begin
- if Is_Non_Empty_List (Freeze_Nodes) then
- F := First (Freeze_Nodes);
-
- if Present (F) then
- Insert_Actions (N, Freeze_Nodes);
- end if;
- end if;
- end Freeze_Before;
-
- -------------------
- -- Freeze_Entity --
- -------------------
-
- function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
- Comp : Entity_Id;
- F_Node : Node_Id;
- Result : List_Id;
- Indx : Node_Id;
- Formal : Entity_Id;
- Atype : Entity_Id;
-
- procedure Check_Current_Instance (Comp_Decl : Node_Id);
- -- Check that an Access or Unchecked_Access attribute with
- -- a prefix which is the current instance type can only be
- -- applied when the type is limited.
-
- function After_Last_Declaration return Boolean;
- -- If Loc is a freeze_entity that appears after the last declaration
- -- in the scope, inhibit error messages on late completion.
-
- procedure Freeze_Record_Type (Rec : Entity_Id);
- -- Freeze each component, handle some representation clauses, and
- -- freeze primitive operations if this is a tagged type.
-
- ----------------------------
- -- After_Last_Declaration --
- ----------------------------
-
- function After_Last_Declaration return Boolean is
- Spec : Node_Id := Parent (Current_Scope);
-
- begin
- if Nkind (Spec) = N_Package_Specification then
- if Present (Private_Declarations (Spec)) then
- return Loc >= Sloc (Last (Private_Declarations (Spec)));
-
- elsif Present (Visible_Declarations (Spec)) then
- return Loc >= Sloc (Last (Visible_Declarations (Spec)));
- else
- return False;
- end if;
-
- else
- return False;
- end if;
- end After_Last_Declaration;
-
- ----------------------------
- -- Check_Current_Instance --
- ----------------------------
-
- procedure Check_Current_Instance (Comp_Decl : Node_Id) is
-
- function Process (N : Node_Id) return Traverse_Result;
- -- Process routine to apply check to given node.
-
- function Process (N : Node_Id) return Traverse_Result is
- begin
- case Nkind (N) is
- when N_Attribute_Reference =>
- if (Attribute_Name (N) = Name_Access
- or else
- Attribute_Name (N) = Name_Unchecked_Access)
- and then Is_Entity_Name (Prefix (N))
- and then Is_Type (Entity (Prefix (N)))
- and then Entity (Prefix (N)) = E
- then
- Error_Msg_N
- ("current instance must be a limited type", Prefix (N));
- return Abandon;
- else
- return OK;
- end if;
-
- when others => return OK;
- end case;
- end Process;
-
- procedure Traverse is new Traverse_Proc (Process);
-
- -- Start of processing for Check_Current_Instance
-
- begin
- Traverse (Comp_Decl);
- end Check_Current_Instance;
-
- ------------------------
- -- Freeze_Record_Type --
- ------------------------
-
- procedure Freeze_Record_Type (Rec : Entity_Id) is
- Comp : Entity_Id;
- Junk : Boolean;
- ADC : Node_Id;
-
- Unplaced_Component : Boolean := False;
- -- Set True if we find at least one component with no component
- -- clause (used to warn about useless Pack pragmas).
-
- Placed_Component : Boolean := False;
- -- Set True if we find at least one component with a component
- -- clause (used to warn about useless Bit_Order pragmas).
-
- begin
- -- Freeze components and embedded subtypes
-
- Comp := First_Entity (Rec);
-
- while Present (Comp) loop
-
- if not Is_Type (Comp) then
- Freeze_And_Append (Etype (Comp), Loc, Result);
- end if;
-
- -- If the component is an access type with an allocator
- -- as default value, the designated type will be frozen
- -- by the corresponding expression in init_proc. In order
- -- to place the freeze node for the designated type before
- -- that for the current record type, freeze it now.
-
- -- Same process if the component is an array of access types,
- -- initialized with an aggregate. If the designated type is
- -- private, it cannot contain allocators, and it is premature
- -- to freeze the type, so we check for this as well.
-
- if Is_Access_Type (Etype (Comp))
- and then Present (Parent (Comp))
- and then Present (Expression (Parent (Comp)))
- and then Nkind (Expression (Parent (Comp))) = N_Allocator
- then
- declare
- Alloc : constant Node_Id := Expression (Parent (Comp));
-
- begin
- -- If component is pointer to a classwide type, freeze
- -- the specific type in the expression being allocated.
- -- The expression may be a subtype indication, in which
- -- case freeze the subtype mark.
-
- if Is_Class_Wide_Type (Designated_Type (Etype (Comp))) then
-
- if Is_Entity_Name (Expression (Alloc)) then
- Freeze_And_Append
- (Entity (Expression (Alloc)), Loc, Result);
- elsif
- Nkind (Expression (Alloc)) = N_Subtype_Indication
- then
- Freeze_And_Append
- (Entity (Subtype_Mark (Expression (Alloc))),
- Loc, Result);
- end if;
- else
- Freeze_And_Append
- (Designated_Type (Etype (Comp)), Loc, Result);
- end if;
- end;
-
- elsif Is_Array_Type (Etype (Comp))
- and then Is_Access_Type (Component_Type (Etype (Comp)))
- and then Present (Parent (Comp))
- and then Nkind (Parent (Comp)) = N_Component_Declaration
- and then Present (Expression (Parent (Comp)))
- and then Nkind (Expression (Parent (Comp))) = N_Aggregate
- and then Is_Fully_Defined
- (Designated_Type (Component_Type (Etype (Comp))))
- then
- Freeze_And_Append
- (Designated_Type
- (Component_Type (Etype (Comp))), Loc, Result);
- end if;
-
- -- Processing for real components (exclude anonymous subtypes)
-
- if Ekind (Comp) = E_Component
- or else Ekind (Comp) = E_Discriminant
- then
- -- Check for error of component clause given for variable
- -- sized type. We have to delay this test till this point,
- -- since the component type has to be frozen for us to know
- -- if it is variable length. We omit this test in a generic
- -- context, it will be applied at instantiation time.
-
- declare
- CC : constant Node_Id := Component_Clause (Comp);
-
- begin
- if Present (CC) then
- Placed_Component := True;
-
- if not Size_Known_At_Compile_Time
- (Underlying_Type (Etype (Comp)))
- and then not Inside_A_Generic
- then
- Error_Msg_N
- ("component clause not allowed for variable " &
- "length component", CC);
- end if;
-
- else
- Unplaced_Component := True;
- end if;
- end;
-
- -- If component clause is present, then deal with the
- -- non-default bit order case. We cannot do this before
- -- the freeze point, because there is no required order
- -- for the component clause and the bit_order clause.
-
- -- We only do this processing for the base type, and in
- -- fact that's important, since otherwise if there are
- -- record subtypes, we could reverse the bits once for
- -- each subtype, which would be incorrect.
-
- if Present (Component_Clause (Comp))
- and then Reverse_Bit_Order (Rec)
- and then Ekind (E) = E_Record_Type
- then
- declare
- CFB : constant Uint := Component_Bit_Offset (Comp);
- CSZ : constant Uint := Esize (Comp);
- CLC : constant Node_Id := Component_Clause (Comp);
- Pos : constant Node_Id := Position (CLC);
- FB : constant Node_Id := First_Bit (CLC);
-
- Storage_Unit_Offset : constant Uint :=
- CFB / System_Storage_Unit;
-
- Start_Bit : constant Uint :=
- CFB mod System_Storage_Unit;
-
- begin
- -- Cases where field goes over storage unit boundary
-
- if Start_Bit + CSZ > System_Storage_Unit then
-
- -- Allow multi-byte field but generate warning
-
- if Start_Bit mod System_Storage_Unit = 0
- and then CSZ mod System_Storage_Unit = 0
- then
- Error_Msg_N
- ("multi-byte field specified with non-standard"
- & " Bit_Order?", CLC);
-
- if Bytes_Big_Endian then
- Error_Msg_N
- ("bytes are not reversed "
- & "(component is big-endian)?", CLC);
- else
- Error_Msg_N
- ("bytes are not reversed "
- & "(component is little-endian)?", CLC);
- end if;
-
- -- Do not allow non-contiguous field
-
- else
- Error_Msg_N
- ("attempt to specify non-contiguous field"
- & " not permitted", CLC);
- Error_Msg_N
- ("\(caused by non-standard Bit_Order "
- & "specified)", CLC);
- end if;
-
- -- Case where field fits in one storage unit
-
- else
- -- Give warning if suspicious component clause
-
- if Intval (FB) >= System_Storage_Unit then
- Error_Msg_N
- ("?Bit_Order clause does not affect " &
- "byte ordering", Pos);
- Error_Msg_Uint_1 :=
- Intval (Pos) + Intval (FB) / System_Storage_Unit;
- Error_Msg_N
- ("?position normalized to ^ before bit " &
- "order interpreted", Pos);
- end if;
-
- -- Here is where we fix up the Component_Bit_Offset
- -- value to account for the reverse bit order.
- -- Some examples of what needs to be done are:
-
- -- First_Bit .. Last_Bit Component_Bit_Offset
- -- old new old new
-
- -- 0 .. 0 7 .. 7 0 7
- -- 0 .. 1 6 .. 7 0 6
- -- 0 .. 2 5 .. 7 0 5
- -- 0 .. 7 0 .. 7 0 4
-
- -- 1 .. 1 6 .. 6 1 6
- -- 1 .. 4 3 .. 6 1 3
- -- 4 .. 7 0 .. 3 4 0
-
- -- The general rule is that the first bit is
- -- is obtained by subtracting the old ending bit
- -- from storage_unit - 1.
-
- Set_Component_Bit_Offset (Comp,
- (Storage_Unit_Offset * System_Storage_Unit)
- + (System_Storage_Unit - 1)
- - (Start_Bit + CSZ - 1));
-
- Set_Normalized_First_Bit (Comp,
- Component_Bit_Offset (Comp) mod System_Storage_Unit);
- end if;
- end;
- end if;
- end if;
-
- Next_Entity (Comp);
- end loop;
-
- -- Check for useless pragma Bit_Order
-
- if not Placed_Component and then Reverse_Bit_Order (Rec) then
- ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
- Error_Msg_N ("?Bit_Order specification has no effect", ADC);
- Error_Msg_N ("\?since no component clauses were specified", ADC);
- end if;
-
- -- Check for useless pragma Pack when all components placed
-
- if Is_Packed (Rec)
- and then not Unplaced_Component
- and then Warn_On_Redundant_Constructs
- then
- Error_Msg_N
- ("?pragma Pack has no effect, no unplaced components",
- Get_Rep_Pragma (Rec, Name_Pack));
- Set_Is_Packed (Rec, False);
- end if;
-
- -- If this is the record corresponding to a remote type,
- -- freeze the remote type here since that is what we are
- -- semantically freeing. This prevents having the freeze node
- -- for that type in an inner scope.
-
- -- Also, Check for controlled components and unchecked unions.
- -- Finally, enforce the restriction that access attributes with
- -- a current instance prefix can only apply to limited types.
-
- if Ekind (Rec) = E_Record_Type then
-
- if Present (Corresponding_Remote_Type (Rec)) then
- Freeze_And_Append
- (Corresponding_Remote_Type (Rec), Loc, Result);
- end if;
-
- Comp := First_Component (Rec);
-
- while Present (Comp) loop
- if Has_Controlled_Component (Etype (Comp))
- or else (Chars (Comp) /= Name_uParent
- and then Is_Controlled (Etype (Comp)))
- or else (Is_Protected_Type (Etype (Comp))
- and then Present
- (Corresponding_Record_Type (Etype (Comp)))
- and then Has_Controlled_Component
- (Corresponding_Record_Type (Etype (Comp))))
- then
- Set_Has_Controlled_Component (Rec);
- exit;
- end if;
-
- if Has_Unchecked_Union (Etype (Comp)) then
- Set_Has_Unchecked_Union (Rec);
- end if;
-
- if Has_Per_Object_Constraint (Comp)
- and then not Is_Limited_Type (Rec)
- then
- -- Scan component declaration for likely misuses of
- -- current instance, either in a constraint or in a
- -- default expression.
-
- Check_Current_Instance (Parent (Comp));
- end if;
-
- Next_Component (Comp);
- end loop;
- end if;
-
- Set_Component_Alignment_If_Not_Set (Rec);
-
- -- For first subtypes, check if there are any fixed-point
- -- fields with component clauses, where we must check the size.
- -- This is not done till the freeze point, since for fixed-point
- -- types, we do not know the size until the type is frozen.
-
- if Is_First_Subtype (Rec) then
- Comp := First_Component (Rec);
-
- while Present (Comp) loop
- if Present (Component_Clause (Comp))
- and then Is_Fixed_Point_Type (Etype (Comp))
- then
- Check_Size
- (Component_Clause (Comp),
- Etype (Comp),
- Esize (Comp),
- Junk);
- end if;
-
- Next_Component (Comp);
- end loop;
- end if;
- end Freeze_Record_Type;
-
- -- Start of processing for Freeze_Entity
-
- begin
- -- Do not freeze if already frozen since we only need one freeze node.
-
- if Is_Frozen (E) then
- return No_List;
-
- -- It is improper to freeze an external entity within a generic
- -- because its freeze node will appear in a non-valid context.
- -- ??? We should probably freeze the entity at that point and insert
- -- the freeze node in a proper place but this proper place is not
- -- easy to find, and the proper scope is not easy to restore. For
- -- now, just wait to get out of the generic to freeze ???
-
- elsif Inside_A_Generic and then External_Ref_In_Generic (E) then
- return No_List;
-
- -- Do not freeze a global entity within an inner scope created during
- -- expansion. A call to subprogram E within some internal procedure
- -- (a stream attribute for example) might require freezing E, but the
- -- freeze node must appear in the same declarative part as E itself.
- -- The two-pass elaboration mechanism in gigi guarantees that E will
- -- be frozen before the inner call is elaborated. We exclude constants
- -- from this test, because deferred constants may be frozen early, and
- -- must be diagnosed (see e.g. 1522-005). If the enclosing subprogram
- -- comes from source, or is a generic instance, then the freeze point
- -- is the one mandated by the language. and we freze the entity.
-
- elsif In_Open_Scopes (Scope (E))
- and then Scope (E) /= Current_Scope
- and then Ekind (E) /= E_Constant
- then
- declare
- S : Entity_Id := Current_Scope;
-
- begin
- while Present (S) loop
- if Is_Overloadable (S) then
- if Comes_From_Source (S)
- or else Is_Generic_Instance (S)
- then
- exit;
- else
- return No_List;
- end if;
- end if;
-
- S := Scope (S);
- end loop;
- end;
- end if;
-
- -- Here to freeze the entity
-
- Result := No_List;
- Set_Is_Frozen (E);
-
- -- Case of entity being frozen is other than a type
-
- if not Is_Type (E) then
-
- -- If entity is exported or imported and does not have an external
- -- name, now is the time to provide the appropriate default name.
- -- Skip this if the entity is stubbed, since we don't need a name
- -- for any stubbed routine.
-
- if (Is_Imported (E) or else Is_Exported (E))
- and then No (Interface_Name (E))
- and then Convention (E) /= Convention_Stubbed
- then
- Set_Encoded_Interface_Name
- (E, Get_Default_External_Name (E));
- end if;
-
- -- For a subprogram, freeze all parameter types and also the return
- -- type (RM 13.14(13)). However skip this for internal subprograms.
- -- This is also the point where any extra formal parameters are
- -- created since we now know whether the subprogram will use
- -- a foreign convention.
-
- if Is_Subprogram (E) then
-
- if not Is_Internal (E) then
-
- declare
- F_Type : Entity_Id;
-
- function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean;
- -- Determines if given type entity is a fat pointer type
- -- used as an argument type or return type to a subprogram
- -- with C or C++ convention set.
-
- --------------------------
- -- Is_Fat_C_Access_Type --
- --------------------------
-
- function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean is
- begin
- return (Convention (E) = Convention_C
- or else
- Convention (E) = Convention_CPP)
- and then Is_Access_Type (T)
- and then Esize (T) > Ttypes.System_Address_Size;
- end Is_Fat_C_Ptr_Type;
-
- begin
- -- Loop through formals
-
- Formal := First_Formal (E);
-
- while Present (Formal) loop
-
- F_Type := Etype (Formal);
- Freeze_And_Append (F_Type, Loc, Result);
-
- if Is_Private_Type (F_Type)
- and then Is_Private_Type (Base_Type (F_Type))
- and then No (Full_View (Base_Type (F_Type)))
- and then not Is_Generic_Type (F_Type)
- and then not Is_Derived_Type (F_Type)
- then
- -- If the type of a formal is incomplete, subprogram
- -- is being frozen prematurely. Within an instance
- -- (but not within a wrapper package) this is an
- -- an artifact of our need to regard the end of an
- -- instantiation as a freeze point. Otherwise it is
- -- a definite error.
- -- and then not Is_Wrapper_Package (Current_Scope) ???
-
- if In_Instance then
- Set_Is_Frozen (E, False);
- return No_List;
-
- elsif not After_Last_Declaration then
- Error_Msg_Node_1 := F_Type;
- Error_Msg
- ("type& must be fully defined before this point",
- Loc);
- end if;
- end if;
-
- -- Check bad use of fat C pointer
-
- if Is_Fat_C_Ptr_Type (F_Type) then
- Error_Msg_Qual_Level := 1;
- Error_Msg_N
- ("?type of & does not correspond to C pointer",
- Formal);
- Error_Msg_Qual_Level := 0;
- end if;
-
- -- Check for unconstrained array in exported foreign
- -- convention case.
-
- if Convention (E) in Foreign_Convention
- and then not Is_Imported (E)
- and then Is_Array_Type (F_Type)
- and then not Is_Constrained (F_Type)
- then
- Error_Msg_Qual_Level := 1;
- Error_Msg_N
- ("?type of argument& is unconstrained array",
- Formal);
- Error_Msg_N
- ("?foreign caller must pass bounds explicitly",
- Formal);
- Error_Msg_Qual_Level := 0;
- end if;
-
- Next_Formal (Formal);
- end loop;
-
- -- Check return type
-
- if Ekind (E) = E_Function then
- Freeze_And_Append (Etype (E), Loc, Result);
-
- if Is_Fat_C_Ptr_Type (Etype (E)) then
- Error_Msg_N
- ("?return type of& does not correspond to C pointer",
- E);
-
- elsif Is_Array_Type (Etype (E))
- and then not Is_Constrained (Etype (E))
- and then not Is_Imported (E)
- and then Convention (E) in Foreign_Convention
- then
- Error_Msg_N
- ("foreign convention function may not " &
- "return unconstrained array", E);
- end if;
- end if;
- end;
- end if;
-
- -- Must freeze its parent first if it is a derived subprogram
-
- if Present (Alias (E)) then
- Freeze_And_Append (Alias (E), Loc, Result);
- end if;
-
- -- If the return type requires a transient scope, and we are on
- -- a target allowing functions to return with a depressed stack
- -- pointer, then we mark the function as requiring this treatment.
-
- if Ekind (E) = E_Function
- and then Functions_Return_By_DSP_On_Target
- and then Requires_Transient_Scope (Etype (E))
- then
- Set_Function_Returns_With_DSP (E);
- end if;
-
- if not Is_Internal (E) then
- Freeze_Subprogram (E);
- end if;
-
- -- Here for other than a subprogram or type
-
- else
- -- If entity has a type, and it is not a generic unit, then
- -- freeze it first (RM 13.14(10))
-
- if Present (Etype (E))
- and then Ekind (E) /= E_Generic_Function
- then
- Freeze_And_Append (Etype (E), Loc, Result);
- end if;
-
- -- For object created by object declaration, perform required
- -- categorization (preelaborate and pure) checks. Defer these
- -- checks to freeze time since pragma Import inhibits default
- -- initialization and thus pragma Import affects these checks.
-
- if Nkind (Declaration_Node (E)) = N_Object_Declaration then
- Validate_Object_Declaration (Declaration_Node (E));
- end if;
-
- -- Check that a constant which has a pragma Volatile[_Components]
- -- or Atomic[_Components] also has a pragma Import (RM C.6(13))
-
- -- Note: Atomic[_Components] also sets Volatile[_Components]
-
- if Ekind (E) = E_Constant
- and then (Has_Volatile_Components (E) or else Is_Volatile (E))
- and then not Is_Imported (E)
- then
- -- Make sure we actually have a pragma, and have not merely
- -- inherited the indication from elsewhere (e.g. an address
- -- clause, which is not good enough in RM terms!)
-
- if Present (Get_Rep_Pragma (E, Name_Atomic)) or else
- Present (Get_Rep_Pragma (E, Name_Atomic_Components)) or else
- Present (Get_Rep_Pragma (E, Name_Volatile)) or else
- Present (Get_Rep_Pragma (E, Name_Volatile_Components))
- then
- Error_Msg_N
- ("stand alone atomic/volatile constant must be imported",
- E);
- end if;
- end if;
-
- -- Static objects require special handling
-
- if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
- and then Is_Statically_Allocated (E)
- then
- Freeze_Static_Object (E);
- end if;
-
- -- Remaining step is to layout objects
-
- if Ekind (E) = E_Variable
- or else
- Ekind (E) = E_Constant
- or else
- Ekind (E) = E_Loop_Parameter
- or else
- Is_Formal (E)
- then
- Layout_Object (E);
- end if;
- end if;
-
- -- Case of a type or subtype being frozen
-
- else
- -- The type may be defined in a generic unit. This can occur when
- -- freezing a generic function that returns the type (which is
- -- defined in a parent unit). It is clearly meaningless to freeze
- -- this type. However, if it is a subtype, its size may be determi-
- -- nable and used in subsequent checks, so might as well try to
- -- compute it.
-
- if Present (Scope (E))
- and then Is_Generic_Unit (Scope (E))
- then
- Check_Compile_Time_Size (E);
- return No_List;
- end if;
-
- -- Deal with special cases of freezing for subtype
-
- if E /= Base_Type (E) then
-
- -- If ancestor subtype present, freeze that first.
- -- Note that this will also get the base type frozen.
-
- Atype := Ancestor_Subtype (E);
-
- if Present (Atype) then
- Freeze_And_Append (Atype, Loc, Result);
-
- -- Otherwise freeze the base type of the entity before
- -- freezing the entity itself, (RM 13.14(14)).
-
- elsif E /= Base_Type (E) then
- Freeze_And_Append (Base_Type (E), Loc, Result);
- end if;
-
- -- For a derived type, freeze its parent type first (RM 13.14(14))
-
- elsif Is_Derived_Type (E) then
- Freeze_And_Append (Etype (E), Loc, Result);
- Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
- end if;
-
- -- For array type, freeze index types and component type first
- -- before freezing the array (RM 13.14(14)).
-
- if Is_Array_Type (E) then
- declare
- Ctyp : constant Entity_Id := Component_Type (E);
-
- Non_Standard_Enum : Boolean := False;
- -- Set true if any of the index types is an enumeration
- -- type with a non-standard representation.
-
- begin
- Freeze_And_Append (Ctyp, Loc, Result);
-
- Indx := First_Index (E);
- while Present (Indx) loop
- Freeze_And_Append (Etype (Indx), Loc, Result);
-
- if Is_Enumeration_Type (Etype (Indx))
- and then Has_Non_Standard_Rep (Etype (Indx))
- then
- Non_Standard_Enum := True;
- end if;
-
- Next_Index (Indx);
- end loop;
-
- -- For base type, propagate flags for component type
-
- if Ekind (E) = E_Array_Type then
- if Is_Controlled (Component_Type (E))
- or else Has_Controlled_Component (Ctyp)
- then
- Set_Has_Controlled_Component (E);
- end if;
-
- if Has_Unchecked_Union (Component_Type (E)) then
- Set_Has_Unchecked_Union (E);
- end if;
- end if;
-
- -- If packing was requested or if the component size was set
- -- explicitly, then see if bit packing is required. This
- -- processing is only done for base types, since all the
- -- representation aspects involved are type-related. This
- -- is not just an optimization, if we start processing the
- -- subtypes, they intefere with the settings on the base
- -- type (this is because Is_Packed has a slightly different
- -- meaning before and after freezing).
-
- if E = Base_Type (E) then
- declare
- Csiz : Uint;
- Esiz : Uint;
-
- begin
- if (Is_Packed (E) or else Has_Pragma_Pack (E))
- and then not Has_Atomic_Components (E)
- and then Known_Static_RM_Size (Ctyp)
- then
- Csiz := UI_Max (RM_Size (Ctyp), 1);
-
- elsif Known_Component_Size (E) then
- Csiz := Component_Size (E);
-
- elsif not Known_Static_Esize (Ctyp) then
- Csiz := Uint_0;
-
- else
- Esiz := Esize (Ctyp);
-
- -- We can set the component size if it is less than
- -- 16, rounding it up to the next storage unit size.
-
- if Esiz <= 8 then
- Csiz := Uint_8;
- elsif Esiz <= 16 then
- Csiz := Uint_16;
- else
- Csiz := Uint_0;
- end if;
-
- -- Set component size up to match alignment if
- -- it would otherwise be less than the alignment.
- -- This deals with cases of types whose alignment
- -- exceeds their sizes (padded types).
-
- if Csiz /= 0 then
- declare
- A : constant Uint := Alignment_In_Bits (Ctyp);
-
- begin
- if Csiz < A then
- Csiz := A;
- end if;
- end;
- end if;
-
- end if;
-
- if 1 <= Csiz and then Csiz <= 64 then
-
- -- We set the component size for all cases 1-64
-
- Set_Component_Size (Base_Type (E), Csiz);
-
- -- Actual packing is not needed for 8,16,32,64
- -- Also not needed for 24 if alignment is 1
-
- if Csiz = 8
- or else Csiz = 16
- or else Csiz = 32
- or else Csiz = 64
- or else (Csiz = 24 and then Alignment (Ctyp) = 1)
- then
- -- Here the array was requested to be packed, but
- -- the packing request had no effect, so Is_Packed
- -- is reset.
-
- -- Note: semantically this means that we lose
- -- track of the fact that a derived type inherited
- -- a pack pragma that was non-effective, but that
- -- seems fine.
-
- -- We regard a Pack pragma as a request to set a
- -- representation characteristic, and this request
- -- may be ignored.
-
- Set_Is_Packed (Base_Type (E), False);
-
- -- In all other cases, packing is indeed needed
-
- else
- Set_Has_Non_Standard_Rep (Base_Type (E));
- Set_Is_Bit_Packed_Array (Base_Type (E));
- Set_Is_Packed (Base_Type (E));
- end if;
- end if;
- end;
- end if;
-
- -- If any of the index types was an enumeration type with
- -- a non-standard rep clause, then we indicate that the
- -- array type is always packed (even if it is not bit packed).
-
- if Non_Standard_Enum then
- Set_Has_Non_Standard_Rep (Base_Type (E));
- Set_Is_Packed (Base_Type (E));
- end if;
- end;
-
- Set_Component_Alignment_If_Not_Set (E);
-
- -- If the array is packed, we must create the packed array
- -- type to be used to actually implement the type. This is
- -- only needed for real array types (not for string literal
- -- types, since they are present only for the front end).
-
- if Is_Packed (E)
- and then Ekind (E) /= E_String_Literal_Subtype
- then
- Create_Packed_Array_Type (E);
- Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
-
- -- Size information of packed array type is copied to the
- -- array type, since this is really the representation.
-
- Set_Size_Info (E, Packed_Array_Type (E));
- Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
- end if;
-
- -- For a class wide type, the corresponding specific type is
- -- frozen as well (RM 13.14(14))
-
- elsif Is_Class_Wide_Type (E) then
- Freeze_And_Append (Root_Type (E), Loc, Result);
-
- -- If the Class_Wide_Type is an Itype (when type is the anonymous
- -- parent of a derived type) and it is a library-level entity,
- -- generate an itype reference for it. Otherwise, its first
- -- explicit reference may be in an inner scope, which will be
- -- rejected by the back-end.
-
- if Is_Itype (E)
- and then Is_Compilation_Unit (Scope (E))
- then
-
- declare
- Ref : Node_Id := Make_Itype_Reference (Loc);
-
- begin
- Set_Itype (Ref, E);
- if No (Result) then
- Result := New_List (Ref);
- else
- Append (Ref, Result);
- end if;
- end;
- end if;
-
- -- For record (sub)type, freeze all the component types (RM
- -- 13.14(14). We test for E_Record_(sub)Type here, rather than
- -- using Is_Record_Type, because we don't want to attempt the
- -- freeze for the case of a private type with record extension
- -- (we will do that later when the full type is frozen).
-
- elsif Ekind (E) = E_Record_Type
- or else Ekind (E) = E_Record_Subtype
- then
- Freeze_Record_Type (E);
-
- -- For a concurrent type, freeze corresponding record type. This
- -- does not correpond to any specific rule in the RM, but the
- -- record type is essentially part of the concurrent type.
- -- Freeze as well all local entities. This includes record types
- -- created for entry parameter blocks, and whatever local entities
- -- may appear in the private part.
-
- elsif Is_Concurrent_Type (E) then
- if Present (Corresponding_Record_Type (E)) then
- Freeze_And_Append
- (Corresponding_Record_Type (E), Loc, Result);
- end if;
-
- Comp := First_Entity (E);
-
- while Present (Comp) loop
- if Is_Type (Comp) then
- Freeze_And_Append (Comp, Loc, Result);
-
- elsif (Ekind (Comp)) /= E_Function then
- Freeze_And_Append (Etype (Comp), Loc, Result);
- end if;
-
- Next_Entity (Comp);
- end loop;
-
- -- Private types are required to point to the same freeze node
- -- as their corresponding full views. The freeze node itself
- -- has to point to the partial view of the entity (because
- -- from the partial view, we can retrieve the full view, but
- -- not the reverse). However, in order to freeze correctly,
- -- we need to freeze the full view. If we are freezing at the
- -- end of a scope (or within the scope of the private type),
- -- the partial and full views will have been swapped, the
- -- full view appears first in the entity chain and the swapping
- -- mechanism enusres that the pointers are properly set (on
- -- scope exit).
-
- -- If we encounter the partial view before the full view
- -- (e.g. when freezing from another scope), we freeze the
- -- full view, and then set the pointers appropriately since
- -- we cannot rely on swapping to fix things up (subtypes in an
- -- outer scope might not get swapped).
-
- elsif Is_Incomplete_Or_Private_Type (E)
- and then not Is_Generic_Type (E)
- then
- -- Case of full view present
-
- if Present (Full_View (E)) then
-
- -- If full view has already been frozen, then no
- -- further processing is required
-
- if Is_Frozen (Full_View (E)) then
-
- Set_Has_Delayed_Freeze (E, False);
- Set_Freeze_Node (E, Empty);
- Check_Debug_Info_Needed (E);
-
- -- Otherwise freeze full view and patch the pointers
-
- else
- if Is_Private_Type (Full_View (E))
- and then Present (Underlying_Full_View (Full_View (E)))
- then
- Freeze_And_Append
- (Underlying_Full_View (Full_View (E)), Loc, Result);
- end if;
-
- Freeze_And_Append (Full_View (E), Loc, Result);
-
- if Has_Delayed_Freeze (E) then
- F_Node := Freeze_Node (Full_View (E));
-
- if Present (F_Node) then
- Set_Freeze_Node (E, F_Node);
- Set_Entity (F_Node, E);
- else
- -- {Incomplete,Private}_Subtypes
- -- with Full_Views constrained by discriminants
-
- Set_Has_Delayed_Freeze (E, False);
- Set_Freeze_Node (E, Empty);
- end if;
- end if;
-
- Check_Debug_Info_Needed (E);
- end if;
-
- -- AI-117 requires that the convention of a partial view
- -- be the same as the convention of the full view. Note
- -- that this is a recognized breach of privacy, but it's
- -- essential for logical consistency of representation,
- -- and the lack of a rule in RM95 was an oversight.
-
- Set_Convention (E, Convention (Full_View (E)));
-
- Set_Size_Known_At_Compile_Time (E,
- Size_Known_At_Compile_Time (Full_View (E)));
-
- -- Size information is copied from the full view to the
- -- incomplete or private view for consistency
-
- -- We skip this is the full view is not a type. This is
- -- very strange of course, and can only happen as a result
- -- of certain illegalities, such as a premature attempt to
- -- derive from an incomplete type.
-
- if Is_Type (Full_View (E)) then
- Set_Size_Info (E, Full_View (E));
- Set_RM_Size (E, RM_Size (Full_View (E)));
- end if;
-
- return Result;
-
- -- Case of no full view present. If entity is derived or subtype,
- -- it is safe to freeze, correctness depends on the frozen status
- -- of parent. Otherwise it is either premature usage, or a Taft
- -- amendment type, so diagnosis is at the point of use and the
- -- type might be frozen later.
-
- elsif E /= Base_Type (E)
- or else Is_Derived_Type (E)
- then
- null;
-
- else
- Set_Is_Frozen (E, False);
- return No_List;
- end if;
-
- -- For access subprogram, freeze types of all formals, the return
- -- type was already frozen, since it is the Etype of the function.
-
- elsif Ekind (E) = E_Subprogram_Type then
- Formal := First_Formal (E);
- while Present (Formal) loop
- Freeze_And_Append (Etype (Formal), Loc, Result);
- Next_Formal (Formal);
- end loop;
-
- -- If the return type requires a transient scope, and we are on
- -- a target allowing functions to return with a depressed stack
- -- pointer, then we mark the function as requiring this treatment.
-
- if Functions_Return_By_DSP_On_Target
- and then Requires_Transient_Scope (Etype (E))
- then
- Set_Function_Returns_With_DSP (E);
- end if;
-
- Freeze_Subprogram (E);
-
- -- For access to a protected subprogram, freeze the equivalent
- -- type (however this is not set if we are not generating code)
- -- or if this is an anonymous type used just for resolution).
-
- elsif Ekind (E) = E_Access_Protected_Subprogram_Type
- and then Operating_Mode = Generate_Code
- and then Present (Equivalent_Type (E))
- then
- Freeze_And_Append (Equivalent_Type (E), Loc, Result);
- end if;
-
- -- Generic types are never seen by the back-end, and are also not
- -- processed by the expander (since the expander is turned off for
- -- generic processing), so we never need freeze nodes for them.
-
- if Is_Generic_Type (E) then
- return Result;
- end if;
-
- -- Some special processing for non-generic types to complete
- -- representation details not known till the freeze point.
-
- if Is_Fixed_Point_Type (E) then
- Freeze_Fixed_Point_Type (E);
-
- elsif Is_Enumeration_Type (E) then
- Freeze_Enumeration_Type (E);
-
- elsif Is_Integer_Type (E) then
- Adjust_Esize_For_Alignment (E);
-
- elsif Is_Access_Type (E)
- and then No (Associated_Storage_Pool (E))
- then
- Check_Restriction (No_Standard_Storage_Pools, E);
- end if;
-
- -- If the current entity is an array or record subtype and has
- -- discriminants used to constrain it, it must not freeze, because
- -- Freeze_Entity nodes force Gigi to process the frozen type.
-
- if Is_Composite_Type (E) then
-
- if Is_Array_Type (E) then
-
- declare
- Index : Node_Id := First_Index (E);
- Expr1 : Node_Id;
- Expr2 : Node_Id;
-
- begin
- while Present (Index) loop
- if Etype (Index) /= Any_Type then
- Get_Index_Bounds (Index, Expr1, Expr2);
-
- for J in 1 .. 2 loop
- if Nkind (Expr1) = N_Identifier
- and then Ekind (Entity (Expr1)) = E_Discriminant
- then
- Set_Has_Delayed_Freeze (E, False);
- Set_Freeze_Node (E, Empty);
- Check_Debug_Info_Needed (E);
- return Result;
- end if;
-
- Expr1 := Expr2;
- end loop;
- end if;
-
- Next_Index (Index);
- end loop;
- end;
-
- elsif Has_Discriminants (E)
- and Is_Constrained (E)
- then
-
- declare
- Constraint : Elmt_Id;
- Expr : Node_Id;
- begin
- Constraint := First_Elmt (Discriminant_Constraint (E));
-
- while Present (Constraint) loop
-
- Expr := Node (Constraint);
- if Nkind (Expr) = N_Identifier
- and then Ekind (Entity (Expr)) = E_Discriminant
- then
- Set_Has_Delayed_Freeze (E, False);
- Set_Freeze_Node (E, Empty);
- Check_Debug_Info_Needed (E);
- return Result;
- end if;
-
- Next_Elmt (Constraint);
- end loop;
- end;
-
- end if;
-
- -- AI-117 requires that all new primitives of a tagged type
- -- must inherit the convention of the full view of the type.
- -- Inherited and overriding operations are defined to inherit
- -- the convention of their parent or overridden subprogram
- -- (also specified in AI-117), and that will have occurred
- -- earlier (in Derive_Subprogram and New_Overloaded_Entity).
- -- Here we set the convention of primitives that are still
- -- convention Ada, which will ensure that any new primitives
- -- inherit the type's convention. Class-wide types can have
- -- a foreign convention inherited from their specific type,
- -- but are excluded from this since they don't have any
- -- associated primitives.
-
- if Is_Tagged_Type (E)
- and then not Is_Class_Wide_Type (E)
- and then Convention (E) /= Convention_Ada
- then
- declare
- Prim_List : constant Elist_Id := Primitive_Operations (E);
- Prim : Elmt_Id := First_Elmt (Prim_List);
-
- begin
- while Present (Prim) loop
- if Convention (Node (Prim)) = Convention_Ada then
- Set_Convention (Node (Prim), Convention (E));
- end if;
-
- Next_Elmt (Prim);
- end loop;
- end;
- end if;
- end if;
-
- -- Now that all types from which E may depend are frozen, see
- -- if the size is known at compile time, if it must be unsigned,
- -- or if strict alignent is required
-
- Check_Compile_Time_Size (E);
- Check_Unsigned_Type (E);
-
- if Base_Type (E) = E then
- Check_Strict_Alignment (E);
- end if;
-
- -- Do not allow a size clause for a type which does not have a size
- -- that is known at compile time
-
- if Has_Size_Clause (E)
- and then not Size_Known_At_Compile_Time (E)
- then
- Error_Msg_N
- ("size clause not allowed for variable length type",
- Size_Clause (E));
- end if;
-
- -- Remaining process is to set/verify the representation information,
- -- in particular the size and alignment values. This processing is
- -- not required for generic types, since generic types do not play
- -- any part in code generation, and so the size and alignment values
- -- for suhc types are irrelevant.
-
- if Is_Generic_Type (E) then
- return Result;
-
- -- Otherwise we call the layout procedure
-
- else
- Layout_Type (E);
- end if;
-
- -- End of freeze processing for type entities
- end if;
-
- -- Here is where we logically freeze the current entity. If it has a
- -- freeze node, then this is the point at which the freeze node is
- -- linked into the result list.
-
- if Has_Delayed_Freeze (E) then
-
- -- If a freeze node is already allocated, use it, otherwise allocate
- -- a new one. The preallocation happens in the case of anonymous base
- -- types, where we preallocate so that we can set First_Subtype_Link.
- -- Note that we reset the Sloc to the current freeze location.
-
- if Present (Freeze_Node (E)) then
- F_Node := Freeze_Node (E);
- Set_Sloc (F_Node, Loc);
-
- else
- F_Node := New_Node (N_Freeze_Entity, Loc);
- Set_Freeze_Node (E, F_Node);
- Set_Access_Types_To_Process (F_Node, No_Elist);
- Set_TSS_Elist (F_Node, No_Elist);
- Set_Actions (F_Node, No_List);
- end if;
-
- Set_Entity (F_Node, E);
-
- if Result = No_List then
- Result := New_List (F_Node);
- else
- Append (F_Node, Result);
- end if;
-
- end if;
-
- -- When a type is frozen, the first subtype of the type is frozen as
- -- well (RM 13.14(15)). This has to be done after freezing the type,
- -- since obviously the first subtype depends on its own base type.
-
- if Is_Type (E) then
- Freeze_And_Append (First_Subtype (E), Loc, Result);
-
- -- If we just froze a tagged non-class wide record, then freeze the
- -- corresponding class-wide type. This must be done after the tagged
- -- type itself is frozen, because the class-wide type refers to the
- -- tagged type which generates the class.
-
- if Is_Tagged_Type (E)
- and then not Is_Class_Wide_Type (E)
- and then Present (Class_Wide_Type (E))
- then
- Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
- end if;
- end if;
-
- Check_Debug_Info_Needed (E);
-
- -- Special handling for subprograms
-
- if Is_Subprogram (E) then
-
- -- If subprogram has address clause then reset Is_Public flag, since
- -- we do not want the backend to generate external references.
-
- if Present (Address_Clause (E))
- and then not Is_Library_Level_Entity (E)
- then
- Set_Is_Public (E, False);
-
- -- If no address clause and not intrinsic, then for imported
- -- subprogram in main unit, generate descriptor if we are in
- -- Propagate_Exceptions mode.
-
- elsif Propagate_Exceptions
- and then Is_Imported (E)
- and then not Is_Intrinsic_Subprogram (E)
- and then Convention (E) /= Convention_Stubbed
- then
- if Result = No_List then
- Result := Empty_List;
- end if;
-
- Generate_Subprogram_Descriptor_For_Imported_Subprogram
- (E, Result);
- end if;
-
- end if;
-
- return Result;
- end Freeze_Entity;
-
- -----------------------------
- -- Freeze_Enumeration_Type --
- -----------------------------
-
- procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
- begin
- if Has_Foreign_Convention (Typ)
- and then not Has_Size_Clause (Typ)
- and then Esize (Typ) < Standard_Integer_Size
- then
- Init_Esize (Typ, Standard_Integer_Size);
-
- else
- Adjust_Esize_For_Alignment (Typ);
- end if;
- end Freeze_Enumeration_Type;
-
- -----------------------
- -- Freeze_Expression --
- -----------------------
-
- procedure Freeze_Expression (N : Node_Id) is
- In_Def_Exp : constant Boolean := In_Default_Expression;
- Typ : Entity_Id;
- Nam : Entity_Id;
- Desig_Typ : Entity_Id;
- P : Node_Id;
- Parent_P : Node_Id;
-
- Freeze_Outside : Boolean := False;
- -- This flag is set true if the entity must be frozen outside the
- -- current subprogram. This happens in the case of expander generated
- -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
- -- not freeze all entities like other bodies, but which nevertheless
- -- may reference entities that have to be frozen before the body and
- -- obviously cannot be frozen inside the body.
-
- function In_Exp_Body (N : Node_Id) return Boolean;
- -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
- -- it is the handled statement sequence of an expander generated
- -- subprogram (init proc, or stream subprogram). If so, it returns
- -- True, otherwise False.
-
- function In_Exp_Body (N : Node_Id) return Boolean is
- P : Node_Id;
-
- begin
- if Nkind (N) = N_Subprogram_Body then
- P := N;
- else
- P := Parent (N);
- end if;
-
- if Nkind (P) /= N_Subprogram_Body then
- return False;
-
- else
- P := Defining_Unit_Name (Specification (P));
-
- if Nkind (P) = N_Defining_Identifier
- and then (Chars (P) = Name_uInit_Proc or else
- Chars (P) = Name_uInput or else
- Chars (P) = Name_uOutput or else
- Chars (P) = Name_uRead or else
- Chars (P) = Name_uWrite)
- then
- return True;
- else
- return False;
- end if;
- end if;
-
- end In_Exp_Body;
-
- -- Start of processing for Freeze_Expression
-
- begin
- -- Immediate return if freezing is inhibited. This flag is set by
- -- the analyzer to stop freezing on generated expressions that would
- -- cause freezing if they were in the source program, but which are
- -- not supposed to freeze, since they are created.
-
- if Must_Not_Freeze (N) then
- return;
- end if;
-
- -- If expression is non-static, then it does not freeze in a default
- -- expression, see section "Handling of Default Expressions" in the
- -- spec of package Sem for further details. Note that we have to
- -- make sure that we actually have a real expression (if we have
- -- a subtype indication, we can't test Is_Static_Expression!)
-
- if In_Def_Exp
- and then Nkind (N) in N_Subexpr
- and then not Is_Static_Expression (N)
- then
- return;
- end if;
-
- -- Freeze type of expression if not frozen already
-
- if Nkind (N) in N_Has_Etype
- and then not Is_Frozen (Etype (N))
- then
- Typ := Etype (N);
- else
- Typ := Empty;
- end if;
-
- -- For entity name, freeze entity if not frozen already. A special
- -- exception occurs for an identifier that did not come from source.
- -- We don't let such identifiers freeze a non-internal entity, i.e.
- -- an entity that did come from source, since such an identifier was
- -- generated by the expander, and cannot have any semantic effect on
- -- the freezing semantics. For example, this stops the parameter of
- -- an initialization procedure from freezing the variable.
-
- if Is_Entity_Name (N)
- and then not Is_Frozen (Entity (N))
- and then (Nkind (N) /= N_Identifier
- or else Comes_From_Source (N)
- or else not Comes_From_Source (Entity (N)))
- then
- Nam := Entity (N);
-
- else
- Nam := Empty;
- end if;
-
- -- For an allocator freeze designated type if not frozen already.
-
- -- For an aggregate whose component type is an access type, freeze
- -- the designated type now, so that its freeze does not appear within
- -- the loop that might be created in the expansion of the aggregate.
- -- If the designated type is a private type without full view, the
- -- expression cannot contain an allocator, so the type is not frozen.
-
- Desig_Typ := Empty;
- case Nkind (N) is
-
- when N_Allocator =>
- Desig_Typ := Designated_Type (Etype (N));
-
- when N_Aggregate =>
- if Is_Array_Type (Etype (N))
- and then Is_Access_Type (Component_Type (Etype (N)))
- then
- Desig_Typ := Designated_Type (Component_Type (Etype (N)));
- end if;
-
- when N_Selected_Component |
- N_Indexed_Component |
- N_Slice =>
-
- if Is_Access_Type (Etype (Prefix (N))) then
- Desig_Typ := Designated_Type (Etype (Prefix (N)));
- end if;
-
- when others =>
- null;
-
- end case;
-
- if Desig_Typ /= Empty
- and then (Is_Frozen (Desig_Typ)
- or else (not Is_Fully_Defined (Desig_Typ)))
- then
- Desig_Typ := Empty;
- end if;
-
- -- All done if nothing needs freezing
-
- if No (Typ)
- and then No (Nam)
- and then No (Desig_Typ)
- then
- return;
- end if;
-
- -- Loop for looking at the right place to insert the freeze nodes
- -- exiting from the loop when it is appropriate to insert the freeze
- -- node before the current node P.
-
- -- Also checks some special exceptions to the freezing rules. These
- -- cases result in a direct return, bypassing the freeze action.
-
- P := N;
- loop
- Parent_P := Parent (P);
-
- -- If we don't have a parent, then we are not in a well-formed
- -- tree. This is an unusual case, but there are some legitimate
- -- situations in which this occurs, notably when the expressions
- -- in the range of a type declaration are resolved. We simply
- -- ignore the freeze request in this case. Is this right ???
-
- if No (Parent_P) then
- return;
- end if;
-
- -- See if we have got to an appropriate point in the tree
-
- case Nkind (Parent_P) is
-
- -- A special test for the exception of (RM 13.14(8)) for the
- -- case of per-object expressions (RM 3.8(18)) occurring in a
- -- component definition or a discrete subtype definition. Note
- -- that we test for a component declaration which includes both
- -- cases we are interested in, and furthermore the tree does not
- -- have explicit nodes for either of these two constructs.
-
- when N_Component_Declaration =>
-
- -- The case we want to test for here is an identifier that is
- -- a per-object expression, this is either a discriminant that
- -- appears in a context other than the component declaration
- -- or it is a reference to the type of the enclosing construct.
-
- -- For either of these cases, we skip the freezing
-
- if not In_Default_Expression
- and then Nkind (N) = N_Identifier
- and then (Present (Entity (N)))
- then
- -- We recognize the discriminant case by just looking for
- -- a reference to a discriminant. It can only be one for
- -- the enclosing construct. Skip freezing in this case.
-
- if Ekind (Entity (N)) = E_Discriminant then
- return;
-
- -- For the case of a reference to the enclosing record,
- -- (or task or protected type), we look for a type that
- -- matches the current scope.
-
- elsif Entity (N) = Current_Scope then
- return;
- end if;
- end if;
-
- -- If we have an enumeration literal that appears as the
- -- choice in the aggregate of an enumeration representation
- -- clause, then freezing does not occur (RM 13.14(9)).
-
- when N_Enumeration_Representation_Clause =>
-
- -- The case we are looking for is an enumeration literal
-
- if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
- and then Is_Enumeration_Type (Etype (N))
- then
- -- If enumeration literal appears directly as the choice,
- -- do not freeze (this is the normal non-overloade case)
-
- if Nkind (Parent (N)) = N_Component_Association
- and then First (Choices (Parent (N))) = N
- then
- return;
-
- -- If enumeration literal appears as the name of a
- -- function which is the choice, then also do not freeze.
- -- This happens in the overloaded literal case, where the
- -- enumeration literal is temporarily changed to a function
- -- call for overloading analysis purposes.
-
- elsif Nkind (Parent (N)) = N_Function_Call
- and then
- Nkind (Parent (Parent (N))) = N_Component_Association
- and then
- First (Choices (Parent (Parent (N)))) = Parent (N)
- then
- return;
- end if;
- end if;
-
- -- Normally if the parent is a handled sequence of statements,
- -- then the current node must be a statement, and that is an
- -- appropriate place to insert a freeze node.
-
- when N_Handled_Sequence_Of_Statements =>
-
- -- An exception occurs when the sequence of statements is
- -- for an expander generated body that did not do the usual
- -- freeze all operation. In this case we usually want to
- -- freeze outside this body, not inside it, and we skip
- -- past the subprogram body that we are inside.
-
- if In_Exp_Body (Parent_P) then
-
- -- However, we *do* want to freeze at this point if we have
- -- an entity to freeze, and that entity is declared *inside*
- -- the body of the expander generated procedure. This case
- -- is recognized by the scope of the type, which is either
- -- the spec for some enclosing body, or (in the case of
- -- init_procs, for which there are no separate specs) the
- -- current scope.
-
- declare
- Subp : constant Node_Id := Parent (Parent_P);
- Cspc : Entity_Id;
-
- begin
- if Nkind (Subp) = N_Subprogram_Body then
- Cspc := Corresponding_Spec (Subp);
-
- if (Present (Typ) and then Scope (Typ) = Cspc)
- or else
- (Present (Nam) and then Scope (Nam) = Cspc)
- then
- exit;
-
- elsif Present (Typ)
- and then Scope (Typ) = Current_Scope
- and then Current_Scope = Defining_Entity (Subp)
- then
- exit;
- end if;
- end if;
- end;
-
- -- If not that exception to the exception, then this is
- -- where we delay the freeze till outside the body.
-
- Parent_P := Parent (Parent_P);
- Freeze_Outside := True;
-
- -- Here if normal case where we are in handled statement
- -- sequence and want to do the insertion right there.
-
- else
- exit;
- end if;
-
- -- If parent is a body or a spec or a block, then the current
- -- node is a statement or declaration and we can insert the
- -- freeze node before it.
-
- when N_Package_Specification |
- N_Package_Body |
- N_Subprogram_Body |
- N_Task_Body |
- N_Protected_Body |
- N_Entry_Body |
- N_Block_Statement => exit;
-
- -- The expander is allowed to define types in any statements list,
- -- so any of the following parent nodes also mark a freezing point
- -- if the actual node is in a list of statements or declarations.
-
- when N_Exception_Handler |
- N_If_Statement |
- N_Elsif_Part |
- N_Case_Statement_Alternative |
- N_Compilation_Unit_Aux |
- N_Selective_Accept |
- N_Accept_Alternative |
- N_Delay_Alternative |
- N_Conditional_Entry_Call |
- N_Entry_Call_Alternative |
- N_Triggering_Alternative |
- N_Abortable_Part |
- N_Freeze_Entity =>
-
- exit when Is_List_Member (P);
-
- -- Note: The N_Loop_Statement is a special case. A type that
- -- appears in the source can never be frozen in a loop (this
- -- occurs only because of a loop expanded by the expander),
- -- so we keep on going. Otherwise we terminate the search.
- -- Same is true of any entity which comes from source. (if they
- -- have a predefined type, that type does not appear to come
- -- from source, but the entity should not be frozen here).
-
- when N_Loop_Statement =>
- exit when not Comes_From_Source (Etype (N))
- and then (No (Nam) or else not Comes_From_Source (Nam));
-
- -- For all other cases, keep looking at parents
-
- when others =>
- null;
- end case;
-
- -- We fall through the case if we did not yet find the proper
- -- place in the free for inserting the freeze node, so climb!
-
- P := Parent_P;
- end loop;
-
- -- If the expression appears in a record or an initialization
- -- procedure, the freeze nodes are collected and attached to
- -- the current scope, to be inserted and analyzed on exit from
- -- the scope, to insure that generated entities appear in the
- -- correct scope. If the expression is a default for a discriminant
- -- specification, the scope is still void. The expression can also
- -- appear in the discriminant part of a private or concurrent type.
-
- -- The other case requiring this special handling is if we are in
- -- a default expression, since in that case we are about to freeze
- -- a static type, and the freeze scope needs to be the outer scope,
- -- not the scope of the subprogram with the default parameter.
-
- -- For default expressions in generic units, the Move_Freeze_Nodes
- -- mechanism (see sem_ch12.adb) takes care of placing them at the
- -- proper place, after the generic unit.
-
- if (In_Def_Exp and not Inside_A_Generic)
- or else Freeze_Outside
- or else (Is_Type (Current_Scope)
- and then (not Is_Concurrent_Type (Current_Scope)
- or else not Has_Completion (Current_Scope)))
- or else Ekind (Current_Scope) = E_Void
- then
- declare
- Loc : constant Source_Ptr := Sloc (Current_Scope);
- Freeze_Nodes : List_Id := No_List;
-
- begin
- if Present (Desig_Typ) then
- Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
- end if;
-
- if Present (Typ) then
- Freeze_And_Append (Typ, Loc, Freeze_Nodes);
- end if;
-
- if Present (Nam) then
- Freeze_And_Append (Nam, Loc, Freeze_Nodes);
- end if;
-
- if Is_Non_Empty_List (Freeze_Nodes) then
-
- if No (Scope_Stack.Table
- (Scope_Stack.Last).Pending_Freeze_Actions)
- then
- Scope_Stack.Table
- (Scope_Stack.Last).Pending_Freeze_Actions :=
- Freeze_Nodes;
- else
- Append_List (Freeze_Nodes, Scope_Stack.Table
- (Scope_Stack.Last).Pending_Freeze_Actions);
- end if;
- end if;
- end;
-
- return;
- end if;
-
- -- Now we have the right place to do the freezing. First, a special
- -- adjustment, if we are in default expression analysis mode, these
- -- freeze actions must not be thrown away (normally all inserted
- -- actions are thrown away in this mode. However, the freeze actions
- -- are from static expressions and one of the important reasons we
- -- are doing this special analysis is to get these freeze actions.
- -- Therefore we turn off the In_Default_Expression mode to propagate
- -- these freeze actions. This also means they get properly analyzed
- -- and expanded.
-
- In_Default_Expression := False;
-
- -- Freeze the designated type of an allocator (RM 13.14(12))
-
- if Present (Desig_Typ) then
- Freeze_Before (P, Desig_Typ);
- end if;
-
- -- Freeze type of expression (RM 13.14(9)). Note that we took care of
- -- the enumeration representation clause exception in the loop above.
-
- if Present (Typ) then
- Freeze_Before (P, Typ);
- end if;
-
- -- Freeze name if one is present (RM 13.14(10))
-
- if Present (Nam) then
- Freeze_Before (P, Nam);
- end if;
-
- In_Default_Expression := In_Def_Exp;
- end Freeze_Expression;
-
- -----------------------------
- -- Freeze_Fixed_Point_Type --
- -----------------------------
-
- -- Certain fixed-point types and subtypes, including implicit base
- -- types and declared first subtypes, have not yet set up a range.
- -- This is because the range cannot be set until the Small and Size
- -- values are known, and these are not known till the type is frozen.
-
- -- To signal this case, Scalar_Range contains an unanalyzed syntactic
- -- range whose bounds are unanalyzed real literals. This routine will
- -- recognize this case, and transform this range node into a properly
- -- typed range with properly analyzed and resolved values.
-
- procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
- Rng : constant Node_Id := Scalar_Range (Typ);
- Lo : constant Node_Id := Low_Bound (Rng);
- Hi : constant Node_Id := High_Bound (Rng);
- Btyp : constant Entity_Id := Base_Type (Typ);
- Brng : constant Node_Id := Scalar_Range (Btyp);
- BLo : constant Node_Id := Low_Bound (Brng);
- BHi : constant Node_Id := High_Bound (Brng);
- Small : constant Ureal := Small_Value (Typ);
- Loval : Ureal;
- Hival : Ureal;
- Atype : Entity_Id;
-
- Actual_Size : Nat;
-
- function Fsize (Lov, Hiv : Ureal) return Nat;
- -- Returns size of type with given bounds. Also leaves these
- -- bounds set as the current bounds of the Typ.
-
- function Fsize (Lov, Hiv : Ureal) return Nat is
- begin
- Set_Realval (Lo, Lov);
- Set_Realval (Hi, Hiv);
- return Minimum_Size (Typ);
- end Fsize;
-
- -- Start of processing for Freeze_Fixed_Point_Type;
-
- begin
- -- If Esize of a subtype has not previously been set, set it now
-
- if Unknown_Esize (Typ) then
- Atype := Ancestor_Subtype (Typ);
-
- if Present (Atype) then
- Set_Size_Info (Typ, Atype);
- else
- Set_Size_Info (Typ, Base_Type (Typ));
- end if;
- end if;
-
- -- Immediate return if the range is already analyzed. This means
- -- that the range is already set, and does not need to be computed
- -- by this routine.
-
- if Analyzed (Rng) then
- return;
- end if;
-
- -- Immediate return if either of the bounds raises Constraint_Error
-
- if Raises_Constraint_Error (Lo)
- or else Raises_Constraint_Error (Hi)
- then
- return;
- end if;
-
- Loval := Realval (Lo);
- Hival := Realval (Hi);
-
- -- Ordinary fixed-point case
-
- if Is_Ordinary_Fixed_Point_Type (Typ) then
-
- -- For the ordinary fixed-point case, we are allowed to fudge the
- -- end-points up or down by small. Generally we prefer to fudge
- -- up, i.e. widen the bounds for non-model numbers so that the
- -- end points are included. However there are cases in which this
- -- cannot be done, and indeed cases in which we may need to narrow
- -- the bounds. The following circuit makes the decision.
-
- -- Note: our terminology here is that Incl_EP means that the
- -- bounds are widened by Small if necessary to include the end
- -- points, and Excl_EP means that the bounds are narrowed by
- -- Small to exclude the end-points if this reduces the size.
-
- -- Note that in the Incl case, all we care about is including the
- -- end-points. In the Excl case, we want to narrow the bounds as
- -- much as permitted by the RM, to give the smallest possible size.
-
- Fudge : declare
- Loval_Incl_EP : Ureal;
- Hival_Incl_EP : Ureal;
-
- Loval_Excl_EP : Ureal;
- Hival_Excl_EP : Ureal;
-
- Size_Incl_EP : Nat;
- Size_Excl_EP : Nat;
-
- Model_Num : Ureal;
- First_Subt : Entity_Id;
- Actual_Lo : Ureal;
- Actual_Hi : Ureal;
-
- begin
- -- First step. Base types are required to be symmetrical. Right
- -- now, the base type range is a copy of the first subtype range.
- -- This will be corrected before we are done, but right away we
- -- need to deal with the case where both bounds are non-negative.
- -- In this case, we set the low bound to the negative of the high
- -- bound, to make sure that the size is computed to include the
- -- required sign. Note that we do not need to worry about the
- -- case of both bounds negative, because the sign will be dealt
- -- with anyway. Furthermore we can't just go making such a bound
- -- symmetrical, since in a twos-complement system, there is an
- -- extra negative value which could not be accomodated on the
- -- positive side.
-
- if Typ = Btyp
- and then not UR_Is_Negative (Loval)
- and then Hival > Loval
- then
- Loval := -Hival;
- Set_Realval (Lo, Loval);
- end if;
-
- -- Compute the fudged bounds. If the number is a model number,
- -- then we do nothing to include it, but we are allowed to
- -- backoff to the next adjacent model number when we exclude
- -- it. If it is not a model number then we straddle the two
- -- values with the model numbers on either side.
-
- Model_Num := UR_Trunc (Loval / Small) * Small;
-
- if Loval = Model_Num then
- Loval_Incl_EP := Model_Num;
- else
- Loval_Incl_EP := Model_Num - Small;
- end if;
-
- -- The low value excluding the end point is Small greater, but
- -- we do not do this exclusion if the low value is positive,
- -- since it can't help the size and could actually hurt by
- -- crossing the high bound.
-
- if UR_Is_Negative (Loval_Incl_EP) then
- Loval_Excl_EP := Loval_Incl_EP + Small;
- else
- Loval_Excl_EP := Loval_Incl_EP;
- end if;
-
- -- Similar processing for upper bound and high value
-
- Model_Num := UR_Trunc (Hival / Small) * Small;
-
- if Hival = Model_Num then
- Hival_Incl_EP := Model_Num;
- else
- Hival_Incl_EP := Model_Num + Small;
- end if;
-
- if UR_Is_Positive (Hival_Incl_EP) then
- Hival_Excl_EP := Hival_Incl_EP - Small;
- else
- Hival_Excl_EP := Hival_Incl_EP;
- end if;
-
- -- One further adjustment is needed. In the case of subtypes,
- -- we cannot go outside the range of the base type, or we get
- -- peculiarities, and the base type range is already set. This
- -- only applies to the Incl values, since clearly the Excl
- -- values are already as restricted as they are allowed to be.
-
- if Typ /= Btyp then
- Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
- Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
- end if;
-
- -- Get size including and excluding end points
-
- Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
- Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
-
- -- No need to exclude end-points if it does not reduce size
-
- if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
- Loval_Excl_EP := Loval_Incl_EP;
- end if;
-
- if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
- Hival_Excl_EP := Hival_Incl_EP;
- end if;
-
- -- Now we set the actual size to be used. We want to use the
- -- bounds fudged up to include the end-points but only if this
- -- can be done without violating a specifically given size
- -- size clause or causing an unacceptable increase in size.
-
- -- Case of size clause given
-
- if Has_Size_Clause (Typ) then
-
- -- Use the inclusive size only if it is consistent with
- -- the explicitly specified size.
-
- if Size_Incl_EP <= RM_Size (Typ) then
- Actual_Lo := Loval_Incl_EP;
- Actual_Hi := Hival_Incl_EP;
- Actual_Size := Size_Incl_EP;
-
- -- If the inclusive size is too large, we try excluding
- -- the end-points (will be caught later if does not work).
-
- else
- Actual_Lo := Loval_Excl_EP;
- Actual_Hi := Hival_Excl_EP;
- Actual_Size := Size_Excl_EP;
- end if;
-
- -- Case of size clause not given
-
- else
- -- If we have a base type whose corresponding first subtype
- -- has an explicit size that is large enough to include our
- -- end-points, then do so. There is no point in working hard
- -- to get a base type whose size is smaller than the specified
- -- size of the first subtype.
-
- First_Subt := First_Subtype (Typ);
-
- if Has_Size_Clause (First_Subt)
- and then Size_Incl_EP <= Esize (First_Subt)
- then
- Actual_Size := Size_Incl_EP;
- Actual_Lo := Loval_Incl_EP;
- Actual_Hi := Hival_Incl_EP;
-
- -- If excluding the end-points makes the size smaller and
- -- results in a size of 8,16,32,64, then we take the smaller
- -- size. For the 64 case, this is compulsory. For the other
- -- cases, it seems reasonable. We like to include end points
- -- if we can, but not at the expense of moving to the next
- -- natural boundary of size.
-
- elsif Size_Incl_EP /= Size_Excl_EP
- and then
- (Size_Excl_EP = 8 or else
- Size_Excl_EP = 16 or else
- Size_Excl_EP = 32 or else
- Size_Excl_EP = 64)
- then
- Actual_Size := Size_Excl_EP;
- Actual_Lo := Loval_Excl_EP;
- Actual_Hi := Hival_Excl_EP;
-
- -- Otherwise we can definitely include the end points
-
- else
- Actual_Size := Size_Incl_EP;
- Actual_Lo := Loval_Incl_EP;
- Actual_Hi := Hival_Incl_EP;
- end if;
-
- -- One pathological case: normally we never fudge a low
- -- bound down, since it would seem to increase the size
- -- (if it has any effect), but for ranges containing a
- -- single value, or no values, the high bound can be
- -- small too large. Consider:
-
- -- type t is delta 2.0**(-14)
- -- range 131072.0 .. 0;
-
- -- That lower bound is *just* outside the range of 32
- -- bits, and does need fudging down in this case. Note
- -- that the bounds will always have crossed here, since
- -- the high bound will be fudged down if necessary, as
- -- in the case of:
-
- -- type t is delta 2.0**(-14)
- -- range 131072.0 .. 131072.0;
-
- -- So we can detect the situation by looking for crossed
- -- bounds, and if the bounds are crossed, and the low
- -- bound is greater than zero, we will always back it
- -- off by small, since this is completely harmless.
-
- if Actual_Lo > Actual_Hi then
- if UR_Is_Positive (Actual_Lo) then
- Actual_Lo := Loval_Incl_EP - Small;
- Actual_Size := Fsize (Actual_Lo, Actual_Hi);
-
- -- And of course, we need to do exactly the same parallel
- -- fudge for flat ranges in the negative region.
-
- elsif UR_Is_Negative (Actual_Hi) then
- Actual_Hi := Hival_Incl_EP + Small;
- Actual_Size := Fsize (Actual_Lo, Actual_Hi);
- end if;
- end if;
- end if;
-
- Set_Realval (Lo, Actual_Lo);
- Set_Realval (Hi, Actual_Hi);
- end Fudge;
-
- -- For the decimal case, none of this fudging is required, since there
- -- are no end-point problems in the decimal case (the end-points are
- -- always included).
-
- else
- Actual_Size := Fsize (Loval, Hival);
- end if;
-
- -- At this stage, the actual size has been calculated and the proper
- -- required bounds are stored in the low and high bounds.
-
- if Actual_Size > 64 then
- Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
- Error_Msg_N
- ("size required (^) for type& too large, maximum is 64", Typ);
- Actual_Size := 64;
- end if;
-
- -- Check size against explicit given size
-
- if Has_Size_Clause (Typ) then
- if Actual_Size > RM_Size (Typ) then
- Error_Msg_Uint_1 := RM_Size (Typ);
- Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
- Error_Msg_NE
- ("size given (^) for type& too small, minimum is ^",
- Size_Clause (Typ), Typ);
-
- else
- Actual_Size := UI_To_Int (Esize (Typ));
- end if;
-
- -- Increase size to next natural boundary if no size clause given
-
- else
- if Actual_Size <= 8 then
- Actual_Size := 8;
- elsif Actual_Size <= 16 then
- Actual_Size := 16;
- elsif Actual_Size <= 32 then
- Actual_Size := 32;
- else
- Actual_Size := 64;
- end if;
-
- Init_Esize (Typ, Actual_Size);
- Adjust_Esize_For_Alignment (Typ);
- end if;
-
- -- If we have a base type, then expand the bounds so that they
- -- extend to the full width of the allocated size in bits, to
- -- avoid junk range checks on intermediate computations.
-
- if Base_Type (Typ) = Typ then
- Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
- Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
- end if;
-
- -- Final step is to reanalyze the bounds using the proper type
- -- and set the Corresponding_Integer_Value fields of the literals.
-
- Set_Etype (Lo, Empty);
- Set_Analyzed (Lo, False);
- Analyze (Lo);
-
- -- Resolve with universal fixed if the base type, and the base
- -- type if it is a subtype. Note we can't resolve the base type
- -- with itself, that would be a reference before definition.
-
- if Typ = Btyp then
- Resolve (Lo, Universal_Fixed);
- else
- Resolve (Lo, Btyp);
- end if;
-
- -- Set corresponding integer value for bound
-
- Set_Corresponding_Integer_Value
- (Lo, UR_To_Uint (Realval (Lo) / Small));
-
- -- Similar processing for high bound
-
- Set_Etype (Hi, Empty);
- Set_Analyzed (Hi, False);
- Analyze (Hi);
-
- if Typ = Btyp then
- Resolve (Hi, Universal_Fixed);
- else
- Resolve (Hi, Btyp);
- end if;
-
- Set_Corresponding_Integer_Value
- (Hi, UR_To_Uint (Realval (Hi) / Small));
-
- -- Set type of range to correspond to bounds
-
- Set_Etype (Rng, Etype (Lo));
-
- -- Set Esize to calculated size and also set RM_Size
-
- Init_Esize (Typ, Actual_Size);
-
- -- Set RM_Size if not already set. If already set, check value
-
- declare
- Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
-
- begin
- if RM_Size (Typ) /= Uint_0 then
- if RM_Size (Typ) < Minsiz then
- Error_Msg_Uint_1 := RM_Size (Typ);
- Error_Msg_Uint_2 := Minsiz;
- Error_Msg_NE
- ("size given (^) for type& too small, minimum is ^",
- Size_Clause (Typ), Typ);
- end if;
-
- else
- Set_RM_Size (Typ, Minsiz);
- end if;
- end;
-
- end Freeze_Fixed_Point_Type;
-
- ------------------
- -- Freeze_Itype --
- ------------------
-
- procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
- L : List_Id;
-
- begin
- Set_Has_Delayed_Freeze (T);
- L := Freeze_Entity (T, Sloc (N));
-
- if Is_Non_Empty_List (L) then
- Insert_Actions (N, L);
- end if;
- end Freeze_Itype;
-
- --------------------------
- -- Freeze_Static_Object --
- --------------------------
-
- procedure Freeze_Static_Object (E : Entity_Id) is
-
- Cannot_Be_Static : exception;
- -- Exception raised if the type of a static object cannot be made
- -- static. This happens if the type depends on non-global objects.
-
- procedure Ensure_Expression_Is_SA (N : Node_Id);
- -- Called to ensure that an expression used as part of a type
- -- definition is statically allocatable, which means that the type
- -- of the expression is statically allocatable, and the expression
- -- is either static, or a reference to a library level constant.
-
- procedure Ensure_Type_Is_SA (Typ : Entity_Id);
- -- Called to mark a type as static, checking that it is possible
- -- to set the type as static. If it is not possible, then the
- -- exception Cannot_Be_Static is raised.
-
- -----------------------------
- -- Ensure_Expression_Is_SA --
- -----------------------------
-
- procedure Ensure_Expression_Is_SA (N : Node_Id) is
- Ent : Entity_Id;
-
- begin
- Ensure_Type_Is_SA (Etype (N));
-
- if Is_Static_Expression (N) then
- return;
-
- elsif Nkind (N) = N_Identifier then
- Ent := Entity (N);
-
- if Present (Ent)
- and then Ekind (Ent) = E_Constant
- and then Is_Library_Level_Entity (Ent)
- then
- return;
- end if;
- end if;
-
- raise Cannot_Be_Static;
- end Ensure_Expression_Is_SA;
-
- -----------------------
- -- Ensure_Type_Is_SA --
- -----------------------
-
- procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
- N : Node_Id;
- C : Entity_Id;
-
- begin
- -- If type is library level, we are all set
-
- if Is_Library_Level_Entity (Typ) then
- return;
- end if;
-
- -- We are also OK if the type is already marked as statically
- -- allocated, which means we processed it before.
-
- if Is_Statically_Allocated (Typ) then
- return;
- end if;
-
- -- Mark type as statically allocated
-
- Set_Is_Statically_Allocated (Typ);
-
- -- Check that it is safe to statically allocate this type
-
- if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
- Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
- Ensure_Expression_Is_SA (Type_High_Bound (Typ));
-
- elsif Is_Array_Type (Typ) then
- N := First_Index (Typ);
- while Present (N) loop
- Ensure_Type_Is_SA (Etype (N));
- Next_Index (N);
- end loop;
-
- Ensure_Type_Is_SA (Component_Type (Typ));
-
- elsif Is_Access_Type (Typ) then
- if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
-
- declare
- F : Entity_Id;
- T : constant Entity_Id := Etype (Designated_Type (Typ));
-
- begin
- if T /= Standard_Void_Type then
- Ensure_Type_Is_SA (T);
- end if;
-
- F := First_Formal (Designated_Type (Typ));
-
- while Present (F) loop
- Ensure_Type_Is_SA (Etype (F));
- Next_Formal (F);
- end loop;
- end;
-
- else
- Ensure_Type_Is_SA (Designated_Type (Typ));
- end if;
-
- elsif Is_Record_Type (Typ) then
- C := First_Entity (Typ);
-
- while Present (C) loop
- if Ekind (C) = E_Discriminant
- or else Ekind (C) = E_Component
- then
- Ensure_Type_Is_SA (Etype (C));
-
- elsif Is_Type (C) then
- Ensure_Type_Is_SA (C);
- end if;
-
- Next_Entity (C);
- end loop;
-
- elsif Ekind (Typ) = E_Subprogram_Type then
- Ensure_Type_Is_SA (Etype (Typ));
-
- C := First_Formal (Typ);
- while Present (C) loop
- Ensure_Type_Is_SA (Etype (C));
- Next_Formal (C);
- end loop;
-
- else
- raise Cannot_Be_Static;
- end if;
- end Ensure_Type_Is_SA;
-
- -- Start of processing for Freeze_Static_Object
-
- begin
- Ensure_Type_Is_SA (Etype (E));
-
- exception
- when Cannot_Be_Static =>
-
- -- If the object that cannot be static is imported or exported,
- -- then we give an error message saying that this object cannot
- -- be imported or exported.
-
- if Is_Imported (E) then
- Error_Msg_N
- ("& cannot be imported (local type is not constant)", E);
-
- -- Otherwise must be exported, something is wrong if compiler
- -- is marking something as statically allocated which cannot be).
-
- else pragma Assert (Is_Exported (E));
- Error_Msg_N
- ("& cannot be exported (local type is not constant)", E);
- end if;
- end Freeze_Static_Object;
-
- -----------------------
- -- Freeze_Subprogram --
- -----------------------
-
- procedure Freeze_Subprogram (E : Entity_Id) is
- Retype : Entity_Id;
- F : Entity_Id;
-
- begin
- -- Subprogram may not have an address clause unless it is imported
-
- if Present (Address_Clause (E)) then
- if not Is_Imported (E) then
- Error_Msg_N
- ("address clause can only be given " &
- "for imported subprogram",
- Name (Address_Clause (E)));
- end if;
- end if;
-
- -- For non-foreign convention subprograms, this is where we create
- -- the extra formals (for accessibility level and constrained bit
- -- information). We delay this till the freeze point precisely so
- -- that we know the convention!
-
- if not Has_Foreign_Convention (E) then
- Create_Extra_Formals (E);
- Set_Mechanisms (E);
-
- -- If this is convention Ada and a Valued_Procedure, that's odd
-
- if Ekind (E) = E_Procedure
- and then Is_Valued_Procedure (E)
- and then Convention (E) = Convention_Ada
- then
- Error_Msg_N
- ("?Valued_Procedure has no effect for convention Ada", E);
- Set_Is_Valued_Procedure (E, False);
- end if;
-
- -- Case of foreign convention
-
- else
- Set_Mechanisms (E);
-
- -- For foreign conventions, do not permit return of an
- -- unconstrained array.
-
- -- Note: we *do* allow a return by descriptor for the VMS case,
- -- though here there is probably more to be done ???
-
- if Ekind (E) = E_Function then
- Retype := Underlying_Type (Etype (E));
-
- -- If no return type, probably some other error, e.g. a
- -- missing full declaration, so ignore.
-
- if No (Retype) then
- null;
-
- -- If the return type is generic, we have emitted a warning
- -- earlier on, and there is nothing else to check here.
- -- Specific instantiations may lead to erroneous behavior.
-
- elsif Is_Generic_Type (Etype (E)) then
- null;
-
- elsif Is_Array_Type (Retype)
- and then not Is_Constrained (Retype)
- and then Mechanism (E) not in Descriptor_Codes
- then
- Error_Msg_NE
- ("convention for& does not permit returning " &
- "unconstrained array type", E, E);
- return;
- end if;
- end if;
-
- -- If any of the formals for an exported foreign convention
- -- subprogram have defaults, then emit an appropriate warning
- -- since this is odd (default cannot be used from non-Ada code)
-
- if Is_Exported (E) then
- F := First_Formal (E);
- while Present (F) loop
- if Present (Default_Value (F)) then
- Error_Msg_N
- ("?parameter cannot be defaulted in non-Ada call",
- Default_Value (F));
- end if;
-
- Next_Formal (F);
- end loop;
- end if;
- end if;
-
- -- For VMS, descriptor mechanisms for parameters are allowed only
- -- for imported subprograms.
-
- if OpenVMS_On_Target then
- if not Is_Imported (E) then
- F := First_Formal (E);
- while Present (F) loop
- if Mechanism (F) in Descriptor_Codes then
- Error_Msg_N
- ("descriptor mechanism for parameter not permitted", F);
- Error_Msg_N
- ("\can only be used for imported subprogram", F);
- end if;
-
- Next_Formal (F);
- end loop;
- end if;
- end if;
-
- end Freeze_Subprogram;
-
- -----------------------
- -- Is_Fully_Defined --
- -----------------------
-
- -- Should this be in Sem_Util ???
-
- function Is_Fully_Defined (T : Entity_Id) return Boolean is
- begin
- if Ekind (T) = E_Class_Wide_Type then
- return Is_Fully_Defined (Etype (T));
- else
- return not Is_Private_Type (T)
- or else Present (Full_View (Base_Type (T)));
- end if;
- end Is_Fully_Defined;
-
- ---------------------------------
- -- Process_Default_Expressions --
- ---------------------------------
-
- procedure Process_Default_Expressions
- (E : Entity_Id;
- After : in out Node_Id)
- is
- Loc : constant Source_Ptr := Sloc (E);
- Dbody : Node_Id;
- Formal : Node_Id;
- Dcopy : Node_Id;
- Dnam : Entity_Id;
-
- begin
- Set_Default_Expressions_Processed (E);
-
- -- A subprogram instance and its associated anonymous subprogram
- -- share their signature. The default expression functions are defined
- -- in the wrapper packages for the anonymous subprogram, and should
- -- not be generated again for the instance.
-
- if Is_Generic_Instance (E)
- and then Present (Alias (E))
- and then Default_Expressions_Processed (Alias (E))
- then
- return;
- end if;
-
- Formal := First_Formal (E);
-
- while Present (Formal) loop
- if Present (Default_Value (Formal)) then
-
- -- We work with a copy of the default expression because we
- -- do not want to disturb the original, since this would mess
- -- up the conformance checking.
-
- Dcopy := New_Copy_Tree (Default_Value (Formal));
-
- -- The analysis of the expression may generate insert actions,
- -- which of course must not be executed. We wrap those actions
- -- in a procedure that is not called, and later on eliminated.
- -- The following cases have no side-effects, and are analyzed
- -- directly.
-
- if Nkind (Dcopy) = N_Identifier
- or else Nkind (Dcopy) = N_Expanded_Name
- or else Nkind (Dcopy) = N_Integer_Literal
- or else (Nkind (Dcopy) = N_Real_Literal
- and then not Vax_Float (Etype (Dcopy)))
- or else Nkind (Dcopy) = N_Character_Literal
- or else Nkind (Dcopy) = N_String_Literal
- or else Nkind (Dcopy) = N_Null
- or else (Nkind (Dcopy) = N_Attribute_Reference
- and then
- Attribute_Name (Dcopy) = Name_Null_Parameter)
-
- then
-
- -- If there is no default function, we must still do a full
- -- analyze call on the default value, to ensure that all
- -- error checks are performed, e.g. those associated with
- -- static evaluation. Note that this branch will always be
- -- taken if the analyzer is turned off (but we still need the
- -- error checks).
-
- -- Note: the setting of parent here is to meet the requirement
- -- that we can only analyze the expression while attached to
- -- the tree. Really the requirement is that the parent chain
- -- be set, we don't actually need to be in the tree.
-
- Set_Parent (Dcopy, Declaration_Node (Formal));
- Analyze (Dcopy);
-
- -- Default expressions are resolved with their own type if the
- -- context is generic, to avoid anomalies with private types.
-
- if Ekind (Scope (E)) = E_Generic_Package then
- Resolve (Dcopy, Etype (Dcopy));
- else
- Resolve (Dcopy, Etype (Formal));
- end if;
-
- -- If that resolved expression will raise constraint error,
- -- then flag the default value as raising constraint error.
- -- This allows a proper error message on the calls.
-
- if Raises_Constraint_Error (Dcopy) then
- Set_Raises_Constraint_Error (Default_Value (Formal));
- end if;
-
- -- If the default is a parameterless call, we use the name of
- -- the called function directly, and there is no body to build.
-
- elsif Nkind (Dcopy) = N_Function_Call
- and then No (Parameter_Associations (Dcopy))
- then
- null;
-
- -- Else construct and analyze the body of a wrapper procedure
- -- that contains an object declaration to hold the expression.
- -- Given that this is done only to complete the analysis, it
- -- simpler to build a procedure than a function which might
- -- involve secondary stack expansion.
-
- else
- Dnam :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
-
- Dbody :=
- Make_Subprogram_Body (Loc,
- Specification =>
- Make_Procedure_Specification (Loc,
- Defining_Unit_Name => Dnam),
-
- Declarations => New_List (
- Make_Object_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc,
- New_Internal_Name ('T')),
- Object_Definition =>
- New_Occurrence_Of (Etype (Formal), Loc),
- Expression => New_Copy_Tree (Dcopy))),
-
- Handled_Statement_Sequence =>
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => New_List));
-
- Set_Scope (Dnam, Scope (E));
- Set_Assignment_OK (First (Declarations (Dbody)));
- Set_Is_Eliminated (Dnam);
- Insert_After (After, Dbody);
- Analyze (Dbody);
- After := Dbody;
- end if;
- end if;
-
- Next_Formal (Formal);
- end loop;
-
- end Process_Default_Expressions;
-
- ----------------------------------------
- -- Set_Component_Alignment_If_Not_Set --
- ----------------------------------------
-
- procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
- begin
- -- Ignore if not base type, subtypes don't need anything
-
- if Typ /= Base_Type (Typ) then
- return;
- end if;
-
- -- Do not override existing representation
-
- if Is_Packed (Typ) then
- return;
-
- elsif Has_Specified_Layout (Typ) then
- return;
-
- elsif Component_Alignment (Typ) /= Calign_Default then
- return;
-
- else
- Set_Component_Alignment
- (Typ, Scope_Stack.Table
- (Scope_Stack.Last).Component_Alignment_Default);
- end if;
- end Set_Component_Alignment_If_Not_Set;
-
- ---------------------------
- -- Set_Debug_Info_Needed --
- ---------------------------
-
- procedure Set_Debug_Info_Needed (T : Entity_Id) is
- begin
- if No (T)
- or else Needs_Debug_Info (T)
- or else Debug_Info_Off (T)
- then
- return;
- else
- Set_Needs_Debug_Info (T);
- end if;
-
- if Is_Object (T) then
- Set_Debug_Info_Needed (Etype (T));
-
- elsif Is_Type (T) then
- Set_Debug_Info_Needed (Etype (T));
-
- if Is_Record_Type (T) then
- declare
- Ent : Entity_Id := First_Entity (T);
- begin
- while Present (Ent) loop
- Set_Debug_Info_Needed (Ent);
- Next_Entity (Ent);
- end loop;
- end;
-
- elsif Is_Array_Type (T) then
- Set_Debug_Info_Needed (Component_Type (T));
-
- declare
- Indx : Node_Id := First_Index (T);
- begin
- while Present (Indx) loop
- Set_Debug_Info_Needed (Etype (Indx));
- Indx := Next_Index (Indx);
- end loop;
- end;
-
- if Is_Packed (T) then
- Set_Debug_Info_Needed (Packed_Array_Type (T));
- end if;
-
- elsif Is_Access_Type (T) then
- Set_Debug_Info_Needed (Directly_Designated_Type (T));
-
- elsif Is_Private_Type (T) then
- Set_Debug_Info_Needed (Full_View (T));
-
- elsif Is_Protected_Type (T) then
- Set_Debug_Info_Needed (Corresponding_Record_Type (T));
- end if;
- end if;
-
- end Set_Debug_Info_Needed;
-
-end Freeze;
projects / msp430-gcc.git / blobdiff