-- Bit packing is never needed for 8, 16, 32, 64
- if Csiz = 8
- or else Csiz = 16
- or else Csiz = 32
- or else Csiz = 64
- then
+ if Addressable (Csiz) then
-- If the Esize of the component is known and equal to
-- the component size then even packing is not needed.
if E /= Base_Type (E) then
- -- Before we do anything else, a specialized test for the case of
- -- a size given for an array where the array needs to be packed,
- -- but was not so the size cannot be honored. This is the case
- -- where implicit packing may apply. The reason we do this so
- -- early is that if we have implicit packing, the layout of the
- -- base type is affected, so we must do this before we freeze
- -- the base type.
+ -- Before we do anything else, a specific test for the case of a
+ -- size given for an array where the array would need to be packed
+ -- in order for the size to be honored, but is not. This is the
+ -- case where implicit packing may apply. The reason we do this so
+ -- early is that, if we have implicit packing, the layout of the
+ -- base type is affected, so we must do this before we freeze the
+ -- base type.
-- We could do this processing only if implicit packing is enabled
-- since in all other cases, the error would be caught by the back
-- end. However, we choose to do the check even if we do not have
-- implicit packing enabled, since this allows us to give a more
- -- useful error message (advising use of pragmas Implicit_Packing
- -- or Pack).
+ -- useful error message (advising use of pragma Implicit_Packing
+ -- or pragma Pack).
if Is_Array_Type (E) then
declare
Hi : Node_Id;
Indx : Node_Id;
- Num_Elmts : Uint;
+ Dim : Uint;
+ Num_Elmts : Uint := Uint_1;
-- Number of elements in array
begin
-- a chance to freeze the base type (and it is that freeze
-- action that causes stuff to be inherited).
+ -- The conditions on the size are identical to those used in
+ -- Freeze_Array_Type to set the Is_Packed flag.
+
if Has_Size_Clause (E)
and then Known_Static_RM_Size (E)
and then not Is_Packed (E)
and then not Has_Pragma_Pack (E)
and then not Has_Component_Size_Clause (E)
and then Known_Static_RM_Size (Ctyp)
- and then RM_Size (Ctyp) < 64
+ and then Rsiz <= 64
+ and then not (Addressable (Rsiz)
+ and then Known_Static_Esize (Ctyp)
+ and then Esize (Ctyp) = Rsiz)
+ and then not (Rsiz mod System_Storage_Unit = 0
+ and then Is_Composite_Type (Ctyp))
and then not Is_Limited_Composite (E)
and then not Is_Packed (Root_Type (E))
and then not Has_Component_Size_Clause (Root_Type (E))
then
-- Compute number of elements in array
- Num_Elmts := Uint_1;
Indx := First_Index (E);
while Present (Indx) loop
Get_Index_Bounds (Indx, Lo, Hi);
goto No_Implicit_Packing;
end if;
- Num_Elmts :=
- Num_Elmts *
- UI_Max (Uint_0,
- Expr_Value (Hi) - Expr_Value (Lo) + 1);
+ Dim := Expr_Value (Hi) - Expr_Value (Lo) + 1;
+
+ if Dim >= 0 then
+ Num_Elmts := Num_Elmts * Dim;
+ else
+ Num_Elmts := Uint_0;
+ end if;
+
Next_Index (Indx);
end loop;
-- What we are looking for here is the situation where
-- the RM_Size given would be exactly right if there was
- -- a pragma Pack (resulting in the component size being
- -- the same as the RM_Size). Furthermore, the component
- -- type size must be an odd size (not a multiple of
- -- storage unit). If the component RM size is an exact
- -- number of storage units that is a power of two, the
- -- array is not packed and has a standard representation.
-
- if RM_Size (E) = Num_Elmts * Rsiz
- and then Rsiz mod System_Storage_Unit /= 0
- then
+ -- a pragma Pack, resulting in the component size being
+ -- the RM_Size of the component type.
+
+ if RM_Size (E) = Num_Elmts * Rsiz then
-- For implicit packing mode, just set the component
- -- size silently.
+ -- size and Freeze_Array_Type will do the rest.
if Implicit_Packing then
- Set_Component_Size (Btyp, Rsiz);
- Set_Is_Bit_Packed_Array (Btyp);
- Set_Is_Packed (Btyp);
- Set_Has_Non_Standard_Rep (Btyp);
+ Set_Component_Size (Btyp, Rsiz);
-- Otherwise give an error message
("\use explicit pragma Pack "
& "or use pragma Implicit_Packing", SZ);
end if;
-
- elsif RM_Size (E) = Num_Elmts * Rsiz
- and then Implicit_Packing
- and then
- (Rsiz / System_Storage_Unit = 1
- or else
- Rsiz / System_Storage_Unit = 2
- or else
- Rsiz / System_Storage_Unit = 4)
- then
- -- Not a packed array, but indicate the desired
- -- component size, for the back-end.
-
- Set_Component_Size (Btyp, Rsiz);
end if;
end if;
end;
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