return Empty;
end Address_Aliased_Entity;
+ -----------------------------------------
+ -- Adjust_Record_For_Reverse_Bit_Order --
+ -----------------------------------------
+
+ procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
+ Max_Machine_Scalar_Size : constant Uint :=
+ UI_From_Int
+ (Standard_Long_Long_Integer_Size);
+ -- We use this as the maximum machine scalar size in the sense of AI-133
+
+ Num_CC : Natural;
+ Comp : Entity_Id;
+ SSU : constant Uint := UI_From_Int (System_Storage_Unit);
+
+ begin
+ -- This first loop through components does two things. First it deals
+ -- with the case of components with component clauses whose length is
+ -- greater than the maximum machine scalar size (either accepting them
+ -- or rejecting as needed). Second, it counts the number of components
+ -- with component clauses whose length does not exceed this maximum for
+ -- later processing.
+
+ Num_CC := 0;
+ Comp := First_Component_Or_Discriminant (R);
+ while Present (Comp) loop
+ declare
+ CC : constant Node_Id := Component_Clause (Comp);
+ Fbit : constant Uint := Static_Integer (First_Bit (CC));
+
+ begin
+ if Present (CC) then
+
+ -- Case of component with size > max machine scalar
+
+ if Esize (Comp) > Max_Machine_Scalar_Size then
+
+ -- Must begin on byte boundary
+
+ if Fbit mod SSU /= 0 then
+ Error_Msg_N
+ ("illegal first bit value for reverse bit order",
+ First_Bit (CC));
+ Error_Msg_Uint_1 := SSU;
+ Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
+
+ Error_Msg_N
+ ("\must be a multiple of ^ if size greater than ^",
+ First_Bit (CC));
+
+ -- Must end on byte boundary
+
+ elsif Esize (Comp) mod SSU /= 0 then
+ Error_Msg_N
+ ("illegal last bit value for reverse bit order",
+ Last_Bit (CC));
+ Error_Msg_Uint_1 := SSU;
+ Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
+
+ Error_Msg_N
+ ("\must be a multiple of ^ if size greater than ^",
+ Last_Bit (CC));
+
+ -- OK, give warning if enabled
+
+ elsif Warn_On_Reverse_Bit_Order then
+ Error_Msg_N
+ ("multi-byte field specified with non-standard"
+ & " Bit_Order?", CC);
+
+ if Bytes_Big_Endian then
+ Error_Msg_N
+ ("\bytes are not reversed "
+ & "(component is big-endian)?", CC);
+ else
+ Error_Msg_N
+ ("\bytes are not reversed "
+ & "(component is little-endian)?", CC);
+ end if;
+ end if;
+
+ -- Case where size is not greater than max machine scalar.
+ -- For now, we just count these.
+
+ else
+ Num_CC := Num_CC + 1;
+ end if;
+ end if;
+ end;
+
+ Next_Component_Or_Discriminant (Comp);
+ end loop;
+
+ -- We need to sort the component clauses on the basis of the Position
+ -- values in the clause, so we can group clauses with the same Position
+ -- together to determine the relevant machine scalar size.
+
+ declare
+ Comps : array (0 .. Num_CC) of Entity_Id;
+ -- Array to collect component and discrimninant entities. The data
+ -- starts at index 1, the 0'th entry is for GNAT.Heap_Sort_A.
+
+ function CP_Lt (Op1, Op2 : Natural) return Boolean;
+ -- Compare routine for Sort (See GNAT.Heap_Sort_A)
+
+ procedure CP_Move (From : Natural; To : Natural);
+ -- Move routine for Sort (see GNAT.Heap_Sort_A)
+
+ Start : Natural;
+ Stop : Natural;
+ -- Start and stop positions in component list of set of components
+ -- with the same starting position (that constitute components in
+ -- a single machine scalar).
+
+ MaxL : Uint;
+ -- Maximum last bit value of any component in this set
+
+ MSS : Uint;
+ -- Corresponding machine scalar size
+
+ -----------
+ -- CP_Lt --
+ -----------
+
+ function CP_Lt (Op1, Op2 : Natural) return Boolean is
+ begin
+ return Position (Component_Clause (Comps (Op1))) <
+ Position (Component_Clause (Comps (Op2)));
+ end CP_Lt;
+
+ -------------
+ -- CP_Move --
+ -------------
+
+ procedure CP_Move (From : Natural; To : Natural) is
+ begin
+ Comps (To) := Comps (From);
+ end CP_Move;
+
+ begin
+ -- Collect the component clauses
+
+ Num_CC := 0;
+ Comp := First_Component_Or_Discriminant (R);
+ while Present (Comp) loop
+ if Present (Component_Clause (Comp))
+ and then Esize (Comp) <= Max_Machine_Scalar_Size
+ then
+ Num_CC := Num_CC + 1;
+ Comps (Num_CC) := Comp;
+ end if;
+
+ Next_Component_Or_Discriminant (Comp);
+ end loop;
+
+ -- Sort by ascending position number
+
+ Sort (Num_CC, CP_Move'Unrestricted_Access, CP_Lt'Unrestricted_Access);
+
+ -- We now have all the components whose size does not exceed the max
+ -- machine scalar value, sorted by starting position. In this loop
+ -- we gather groups of clauses starting at the same position, to
+ -- process them in accordance with Ada 2005 AI-133.
+
+ Stop := 0;
+ while Stop < Num_CC loop
+ Start := Stop + 1;
+ Stop := Start;
+ MaxL :=
+ Static_Integer (Last_Bit (Component_Clause (Comps (Start))));
+ while Stop < Num_CC loop
+ if Static_Integer
+ (Position (Component_Clause (Comps (Stop + 1)))) =
+ Static_Integer
+ (Position (Component_Clause (Comps (Stop))))
+ then
+ Stop := Stop + 1;
+ MaxL :=
+ UI_Max
+ (MaxL,
+ Static_Integer
+ (Last_Bit (Component_Clause (Comps (Stop)))));
+ else
+ exit;
+ end if;
+ end loop;
+
+ -- Now we have a group of component clauses from Start to Stop
+ -- whose positions are identical, and MaxL is the maximum last bit
+ -- value of any of these components.
+
+ -- We need to determine the corresponding machine scalar size.
+ -- This loop assumes that machine scalar sizes are even, and that
+ -- each possible machine scalar has twice as many bits as the
+ -- next smaller one.
+
+ MSS := Max_Machine_Scalar_Size;
+ while MSS mod 2 = 0
+ and then (MSS / 2) >= SSU
+ and then (MSS / 2) > MaxL
+ loop
+ MSS := MSS / 2;
+ end loop;
+
+ -- 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 for the case of a machine scalar size of 8 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 machine scalar size - 1.
+
+ for C in Start .. Stop loop
+ declare
+ Comp : constant Entity_Id := Comps (C);
+ CC : constant Node_Id := Component_Clause (Comp);
+ LB : constant Uint := Static_Integer (Last_Bit (CC));
+ NFB : constant Uint := MSS - Uint_1 - LB;
+ NLB : constant Uint := NFB + Esize (Comp) - 1;
+ Pos : constant Uint := Static_Integer (Position (CC));
+
+ begin
+ if Warn_On_Reverse_Bit_Order then
+ Error_Msg_Uint_1 := MSS;
+ Error_Msg_N
+ ("?reverse bit order in machine " &
+ "scalar of length^", First_Bit (CC));
+ Error_Msg_Uint_1 := NFB;
+ Error_Msg_Uint_2 := NLB;
+
+ if Bytes_Big_Endian then
+ Error_Msg_NE
+ ("?\big-endian range for component & is ^ .. ^",
+ First_Bit (CC), Comp);
+ else
+ Error_Msg_NE
+ ("?\little-endian range for component & is ^ .. ^",
+ First_Bit (CC), Comp);
+ end if;
+ end if;
+
+ Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
+ Set_Normalized_First_Bit (Comp, NFB mod SSU);
+ end;
+ end loop;
+ end loop;
+ end;
+ end Adjust_Record_For_Reverse_Bit_Order;
+
--------------------------------------
-- Alignment_Check_For_Esize_Change --
--------------------------------------
end if;
if Present (Subp) then
- if Is_Abstract (Subp) then
+ if Is_Abstract_Subprogram (Subp) then
Error_Msg_N ("stream subprogram must not be abstract", Expr);
return;
end if;
Etyp := Etype (U_Ent);
end if;
- -- Check size, note that Gigi is in charge of checking
- -- that the size of an array or record type is OK. Also
- -- we do not check the size in the ordinary fixed-point
- -- case, since it is too early to do so (there may be a
- -- subsequent small clause that affects the size). We can
- -- check the size if a small clause has already been given.
+ -- Check size, note that Gigi is in charge of checking that the
+ -- size of an array or record type is OK. Also we do not check
+ -- the size in the ordinary fixed-point case, since it is too
+ -- early to do so (there may be subsequent small clause that
+ -- affects the size). We can check the size if a small clause
+ -- has already been given.
if not Is_Ordinary_Fixed_Point_Type (U_Ent)
or else Has_Small_Clause (U_Ent)
if Is_Type (U_Ent) then
Set_RM_Size (U_Ent, Size);
- -- For scalar types, increase Object_Size to power of 2,
- -- but not less than a storage unit in any case (i.e.,
- -- normally this means it will be byte addressable).
+ -- For scalar types, increase Object_Size to power of 2, but
+ -- not less than a storage unit in any case (i.e., normally
+ -- this means it will be byte addressable).
if Is_Scalar_Type (U_Ent) then
if Size <= System_Storage_Unit then
then
Error_Msg_N ("Value_Size already given for &", Nam);
+ elsif Is_Array_Type (U_Ent)
+ and then not Is_Constrained (U_Ent)
+ then
+ Error_Msg_N
+ ("Value_Size cannot be given for unconstrained array", Nam);
+
else
if Is_Elementary_Type (U_Ent) then
Check_Size (Expr, U_Ent, Size, Biased);
-- Clear any existing component clauses for the type (this happens
-- with derived types, where we are now overriding the original)
- Fent := First_Entity (Rectype);
-
- Comp := Fent;
+ Comp := First_Component_Or_Discriminant (Rectype);
while Present (Comp) loop
- if Ekind (Comp) = E_Component
- or else Ekind (Comp) = E_Discriminant
- then
- Set_Component_Clause (Comp, Empty);
- end if;
-
- Next_Entity (Comp);
+ Set_Component_Clause (Comp, Empty);
+ Next_Component_Or_Discriminant (Comp);
end loop;
-- All done if no component clauses
-- it at the start of the record (otherwise gigi may place it after
-- other fields that have rep clauses).
+ Fent := First_Entity (Rectype);
+
if Nkind (Fent) = N_Defining_Identifier
and then Chars (Fent) = Name_uTag
then
then
-- Nothing to do if at least one component with no component clause
- Comp := First_Entity (Rectype);
+ Comp := First_Component_Or_Discriminant (Rectype);
while Present (Comp) loop
- if Ekind (Comp) = E_Component
- or else Ekind (Comp) = E_Discriminant
- then
- exit when No (Component_Clause (Comp));
- end if;
-
- Next_Entity (Comp);
+ exit when No (Component_Clause (Comp));
+ Next_Component_Or_Discriminant (Comp);
end loop;
-- If we fall out of loop, all components have component clauses
-- Check missing components if Complete_Representation pragma appeared
if Present (CR_Pragma) then
- Comp := First_Entity (Rectype);
+ Comp := First_Component_Or_Discriminant (Rectype);
while Present (Comp) loop
- if Ekind (Comp) = E_Component
- or else
- Ekind (Comp) = E_Discriminant
- then
- if No (Component_Clause (Comp)) then
- Error_Msg_NE
- ("missing component clause for &", CR_Pragma, Comp);
- end if;
+ if No (Component_Clause (Comp)) then
+ Error_Msg_NE
+ ("missing component clause for &", CR_Pragma, Comp);
end if;
- Next_Entity (Comp);
+ Next_Component_Or_Discriminant (Comp);
end loop;
end if;
end Analyze_Record_Representation_Clause;
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