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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ P A K D --
-- --
-- B o d y --
-- --
-- $Revision$
-- --
-- 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. --
-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Checks; use Checks;
with Einfo; use Einfo;
with Exp_Dbug; use Exp_Dbug;
with Exp_Util; use Exp_Util;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Ch8; use Sem_Ch8;
with Sem_Ch13; use Sem_Ch13;
with Sem_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Snames; use Snames;
with Stand; use Stand;
with Targparm; use Targparm;
with Tbuild; use Tbuild;
with Ttypes; use Ttypes;
with Uintp; use Uintp;
package body Exp_Pakd is
---------------------------
-- Endian Considerations --
---------------------------
-- As described in the specification, bit numbering in a packed array
-- is consistent with bit numbering in a record representation clause,
-- and hence dependent on the endianness of the machine:
-- For little-endian machines, element zero is at the right hand end
-- (low order end) of a bit field.
-- For big-endian machines, element zero is at the left hand end
-- (high order end) of a bit field.
-- The shifts that are used to right justify a field therefore differ
-- in the two cases. For the little-endian case, we can simply use the
-- bit number (i.e. the element number * element size) as the count for
-- a right shift. For the big-endian case, we have to subtract the shift
-- count from an appropriate constant to use in the right shift. We use
-- rotates instead of shifts (which is necessary in the store case to
-- preserve other fields), and we expect that the backend will be able
-- to change the right rotate into a left rotate, avoiding the subtract,
-- if the architecture provides such an instruction.
----------------------------------------------
-- Entity Tables for Packed Access Routines --
----------------------------------------------
-- For the cases of component size = 3,5-7,9-15,17-31,33-63 we call
-- library routines. This table is used to obtain the entity for the
-- proper routine.
type E_Array is array (Int range 01 .. 63) of RE_Id;
-- Array of Bits_nn entities. Note that we do not use library routines
-- for the 8-bit and 16-bit cases, but we still fill in the table, using
-- entries from System.Unsigned, because we also use this table for
-- certain special unchecked conversions in the big-endian case.
Bits_Id : constant E_Array :=
(01 => RE_Bits_1,
02 => RE_Bits_2,
03 => RE_Bits_03,
04 => RE_Bits_4,
05 => RE_Bits_05,
06 => RE_Bits_06,
07 => RE_Bits_07,
08 => RE_Unsigned_8,
09 => RE_Bits_09,
10 => RE_Bits_10,
11 => RE_Bits_11,
12 => RE_Bits_12,
13 => RE_Bits_13,
14 => RE_Bits_14,
15 => RE_Bits_15,
16 => RE_Unsigned_16,
17 => RE_Bits_17,
18 => RE_Bits_18,
19 => RE_Bits_19,
20 => RE_Bits_20,
21 => RE_Bits_21,
22 => RE_Bits_22,
23 => RE_Bits_23,
24 => RE_Bits_24,
25 => RE_Bits_25,
26 => RE_Bits_26,
27 => RE_Bits_27,
28 => RE_Bits_28,
29 => RE_Bits_29,
30 => RE_Bits_30,
31 => RE_Bits_31,
32 => RE_Unsigned_32,
33 => RE_Bits_33,
34 => RE_Bits_34,
35 => RE_Bits_35,
36 => RE_Bits_36,
37 => RE_Bits_37,
38 => RE_Bits_38,
39 => RE_Bits_39,
40 => RE_Bits_40,
41 => RE_Bits_41,
42 => RE_Bits_42,
43 => RE_Bits_43,
44 => RE_Bits_44,
45 => RE_Bits_45,
46 => RE_Bits_46,
47 => RE_Bits_47,
48 => RE_Bits_48,
49 => RE_Bits_49,
50 => RE_Bits_50,
51 => RE_Bits_51,
52 => RE_Bits_52,
53 => RE_Bits_53,
54 => RE_Bits_54,
55 => RE_Bits_55,
56 => RE_Bits_56,
57 => RE_Bits_57,
58 => RE_Bits_58,
59 => RE_Bits_59,
60 => RE_Bits_60,
61 => RE_Bits_61,
62 => RE_Bits_62,
63 => RE_Bits_63);
-- Array of Get routine entities. These are used to obtain an element
-- from a packed array. The N'th entry is used to obtain elements from
-- a packed array whose component size is N. RE_Null is used as a null
-- entry, for the cases where a library routine is not used.
Get_Id : constant E_Array :=
(01 => RE_Null,
02 => RE_Null,
03 => RE_Get_03,
04 => RE_Null,
05 => RE_Get_05,
06 => RE_Get_06,
07 => RE_Get_07,
08 => RE_Null,
09 => RE_Get_09,
10 => RE_Get_10,
11 => RE_Get_11,
12 => RE_Get_12,
13 => RE_Get_13,
14 => RE_Get_14,
15 => RE_Get_15,
16 => RE_Null,
17 => RE_Get_17,
18 => RE_Get_18,
19 => RE_Get_19,
20 => RE_Get_20,
21 => RE_Get_21,
22 => RE_Get_22,
23 => RE_Get_23,
24 => RE_Get_24,
25 => RE_Get_25,
26 => RE_Get_26,
27 => RE_Get_27,
28 => RE_Get_28,
29 => RE_Get_29,
30 => RE_Get_30,
31 => RE_Get_31,
32 => RE_Null,
33 => RE_Get_33,
34 => RE_Get_34,
35 => RE_Get_35,
36 => RE_Get_36,
37 => RE_Get_37,
38 => RE_Get_38,
39 => RE_Get_39,
40 => RE_Get_40,
41 => RE_Get_41,
42 => RE_Get_42,
43 => RE_Get_43,
44 => RE_Get_44,
45 => RE_Get_45,
46 => RE_Get_46,
47 => RE_Get_47,
48 => RE_Get_48,
49 => RE_Get_49,
50 => RE_Get_50,
51 => RE_Get_51,
52 => RE_Get_52,
53 => RE_Get_53,
54 => RE_Get_54,
55 => RE_Get_55,
56 => RE_Get_56,
57 => RE_Get_57,
58 => RE_Get_58,
59 => RE_Get_59,
60 => RE_Get_60,
61 => RE_Get_61,
62 => RE_Get_62,
63 => RE_Get_63);
-- Array of Get routine entities to be used in the case where the packed
-- array is itself a component of a packed structure, and therefore may
-- not be fully aligned. This only affects the even sizes, since for the
-- odd sizes, we do not get any fixed alignment in any case.
GetU_Id : constant E_Array :=
(01 => RE_Null,
02 => RE_Null,
03 => RE_Get_03,
04 => RE_Null,
05 => RE_Get_05,
06 => RE_GetU_06,
07 => RE_Get_07,
08 => RE_Null,
09 => RE_Get_09,
10 => RE_GetU_10,
11 => RE_Get_11,
12 => RE_GetU_12,
13 => RE_Get_13,
14 => RE_GetU_14,
15 => RE_Get_15,
16 => RE_Null,
17 => RE_Get_17,
18 => RE_GetU_18,
19 => RE_Get_19,
20 => RE_GetU_20,
21 => RE_Get_21,
22 => RE_GetU_22,
23 => RE_Get_23,
24 => RE_GetU_24,
25 => RE_Get_25,
26 => RE_GetU_26,
27 => RE_Get_27,
28 => RE_GetU_28,
29 => RE_Get_29,
30 => RE_GetU_30,
31 => RE_Get_31,
32 => RE_Null,
33 => RE_Get_33,
34 => RE_GetU_34,
35 => RE_Get_35,
36 => RE_GetU_36,
37 => RE_Get_37,
38 => RE_GetU_38,
39 => RE_Get_39,
40 => RE_GetU_40,
41 => RE_Get_41,
42 => RE_GetU_42,
43 => RE_Get_43,
44 => RE_GetU_44,
45 => RE_Get_45,
46 => RE_GetU_46,
47 => RE_Get_47,
48 => RE_GetU_48,
49 => RE_Get_49,
50 => RE_GetU_50,
51 => RE_Get_51,
52 => RE_GetU_52,
53 => RE_Get_53,
54 => RE_GetU_54,
55 => RE_Get_55,
56 => RE_GetU_56,
57 => RE_Get_57,
58 => RE_GetU_58,
59 => RE_Get_59,
60 => RE_GetU_60,
61 => RE_Get_61,
62 => RE_GetU_62,
63 => RE_Get_63);
-- Array of Set routine entities. These are used to assign an element
-- of a packed array. The N'th entry is used to assign elements for
-- a packed array whose component size is N. RE_Null is used as a null
-- entry, for the cases where a library routine is not used.
Set_Id : E_Array :=
(01 => RE_Null,
02 => RE_Null,
03 => RE_Set_03,
04 => RE_Null,
05 => RE_Set_05,
06 => RE_Set_06,
07 => RE_Set_07,
08 => RE_Null,
09 => RE_Set_09,
10 => RE_Set_10,
11 => RE_Set_11,
12 => RE_Set_12,
13 => RE_Set_13,
14 => RE_Set_14,
15 => RE_Set_15,
16 => RE_Null,
17 => RE_Set_17,
18 => RE_Set_18,
19 => RE_Set_19,
20 => RE_Set_20,
21 => RE_Set_21,
22 => RE_Set_22,
23 => RE_Set_23,
24 => RE_Set_24,
25 => RE_Set_25,
26 => RE_Set_26,
27 => RE_Set_27,
28 => RE_Set_28,
29 => RE_Set_29,
30 => RE_Set_30,
31 => RE_Set_31,
32 => RE_Null,
33 => RE_Set_33,
34 => RE_Set_34,
35 => RE_Set_35,
36 => RE_Set_36,
37 => RE_Set_37,
38 => RE_Set_38,
39 => RE_Set_39,
40 => RE_Set_40,
41 => RE_Set_41,
42 => RE_Set_42,
43 => RE_Set_43,
44 => RE_Set_44,
45 => RE_Set_45,
46 => RE_Set_46,
47 => RE_Set_47,
48 => RE_Set_48,
49 => RE_Set_49,
50 => RE_Set_50,
51 => RE_Set_51,
52 => RE_Set_52,
53 => RE_Set_53,
54 => RE_Set_54,
55 => RE_Set_55,
56 => RE_Set_56,
57 => RE_Set_57,
58 => RE_Set_58,
59 => RE_Set_59,
60 => RE_Set_60,
61 => RE_Set_61,
62 => RE_Set_62,
63 => RE_Set_63);
-- Array of Set routine entities to be used in the case where the packed
-- array is itself a component of a packed structure, and therefore may
-- not be fully aligned. This only affects the even sizes, since for the
-- odd sizes, we do not get any fixed alignment in any case.
SetU_Id : E_Array :=
(01 => RE_Null,
02 => RE_Null,
03 => RE_Set_03,
04 => RE_Null,
05 => RE_Set_05,
06 => RE_SetU_06,
07 => RE_Set_07,
08 => RE_Null,
09 => RE_Set_09,
10 => RE_SetU_10,
11 => RE_Set_11,
12 => RE_SetU_12,
13 => RE_Set_13,
14 => RE_SetU_14,
15 => RE_Set_15,
16 => RE_Null,
17 => RE_Set_17,
18 => RE_SetU_18,
19 => RE_Set_19,
20 => RE_SetU_20,
21 => RE_Set_21,
22 => RE_SetU_22,
23 => RE_Set_23,
24 => RE_SetU_24,
25 => RE_Set_25,
26 => RE_SetU_26,
27 => RE_Set_27,
28 => RE_SetU_28,
29 => RE_Set_29,
30 => RE_SetU_30,
31 => RE_Set_31,
32 => RE_Null,
33 => RE_Set_33,
34 => RE_SetU_34,
35 => RE_Set_35,
36 => RE_SetU_36,
37 => RE_Set_37,
38 => RE_SetU_38,
39 => RE_Set_39,
40 => RE_SetU_40,
41 => RE_Set_41,
42 => RE_SetU_42,
43 => RE_Set_43,
44 => RE_SetU_44,
45 => RE_Set_45,
46 => RE_SetU_46,
47 => RE_Set_47,
48 => RE_SetU_48,
49 => RE_Set_49,
50 => RE_SetU_50,
51 => RE_Set_51,
52 => RE_SetU_52,
53 => RE_Set_53,
54 => RE_SetU_54,
55 => RE_Set_55,
56 => RE_SetU_56,
57 => RE_Set_57,
58 => RE_SetU_58,
59 => RE_Set_59,
60 => RE_SetU_60,
61 => RE_Set_61,
62 => RE_SetU_62,
63 => RE_Set_63);
-----------------------
-- Local Subprograms --
-----------------------
procedure Compute_Linear_Subscript
(Atyp : Entity_Id;
N : Node_Id;
Subscr : out Node_Id);
-- Given a constrained array type Atyp, and an indexed component node
-- N referencing an array object of this type, build an expression of
-- type Standard.Integer representing the zero-based linear subscript
-- value. This expression includes any required range checks.
procedure Convert_To_PAT_Type (Aexp : Node_Id);
-- Given an expression of a packed array type, builds a corresponding
-- expression whose type is the implementation type used to represent
-- the packed array. Aexp is analyzed and resolved on entry and on exit.
function Known_Aligned_Enough (Obj : Node_Id; Csiz : Nat) return Boolean;
-- There are two versions of the Set routines, the ones used when the
-- object is known to be sufficiently well aligned given the number of
-- bits, and the ones used when the object is not known to be aligned.
-- This routine is used to determine which set to use. Obj is a reference
-- to the object, and Csiz is the component size of the packed array.
-- True is returned if the alignment of object is known to be sufficient,
-- defined as 1 for odd bit sizes, 4 for bit sizes divisible by 4, and
-- 2 otherwise.
function Make_Shift_Left (N : Node_Id; S : Node_Id) return Node_Id;
-- Build a left shift node, checking for the case of a shift count of zero
function Make_Shift_Right (N : Node_Id; S : Node_Id) return Node_Id;
-- Build a right shift node, checking for the case of a shift count of zero
function RJ_Unchecked_Convert_To
(Typ : Entity_Id;
Expr : Node_Id)
return Node_Id;
-- The packed array code does unchecked conversions which in some cases
-- may involve non-discrete types with differing sizes. The semantics of
-- such conversions is potentially endian dependent, and the effect we
-- want here for such a conversion is to do the conversion in size as
-- though numeric items are involved, and we extend or truncate on the
-- left side. This happens naturally in the little-endian case, but in
-- the big endian case we can get left justification, when what we want
-- is right justification. This routine does the unchecked conversion in
-- a stepwise manner to ensure that it gives the expected result. Hence
-- the name (RJ = Right justified). The parameters Typ and Expr are as
-- for the case of a normal Unchecked_Convert_To call.
procedure Setup_Enumeration_Packed_Array_Reference (N : Node_Id);
-- This routine is called in the Get and Set case for arrays that are
-- packed but not bit-packed, meaning that they have at least one
-- subscript that is of an enumeration type with a non-standard
-- representation. This routine modifies the given node to properly
-- reference the corresponding packed array type.
procedure Setup_Inline_Packed_Array_Reference
(N : Node_Id;
Atyp : Entity_Id;
Obj : in out Node_Id;
Cmask : out Uint;
Shift : out Node_Id);
-- This procedure performs common processing on the N_Indexed_Component
-- parameter given as N, whose prefix is a reference to a packed array.
-- This is used for the get and set when the component size is 1,2,4
-- or for other component sizes when the packed array type is a modular
-- type (i.e. the cases that are handled with inline code).
--
-- On entry:
--
-- N is the N_Indexed_Component node for the packed array reference
--
-- Atyp is the constrained array type (the actual subtype has been
-- computed if necessary to obtain the constraints, but this is still
-- the original array type, not the Packed_Array_Type value).
--
-- Obj is the object which is to be indexed. It is always of type Atyp.
--
-- On return:
--
-- Obj is the object containing the desired bit field. It is of type
-- Unsigned or Long_Long_Unsigned, and is either the entire value,
-- for the small static case, or the proper selected byte from the
-- array in the large or dynamic case. This node is analyzed and
-- resolved on return.
--
-- Shift is a node representing the shift count to be used in the
-- rotate right instruction that positions the field for access.
-- This node is analyzed and resolved on return.
--
-- Cmask is a mask corresponding to the width of the component field.
-- Its value is 2 ** Csize - 1 (e.g. 2#1111# for component size of 4).
--
-- Note: in some cases the call to this routine may generate actions
-- (for handling multi-use references and the generation of the packed
-- array type on the fly). Such actions are inserted into the tree
-- directly using Insert_Action.
------------------------------
-- Compute_Linear_Subcsript --
------------------------------
procedure Compute_Linear_Subscript
(Atyp : Entity_Id;
N : Node_Id;
Subscr : out Node_Id)
is
Loc : constant Source_Ptr := Sloc (N);
Oldsub : Node_Id;
Newsub : Node_Id;
Indx : Node_Id;
Styp : Entity_Id;
begin
Subscr := Empty;
-- Loop through dimensions
Indx := First_Index (Atyp);
Oldsub := First (Expressions (N));
while Present (Indx) loop
Styp := Etype (Indx);
Newsub := Relocate_Node (Oldsub);
-- Get expression for the subscript value. First, if Do_Range_Check
-- is set on a subscript, then we must do a range check against the
-- original bounds (not the bounds of the packed array type). We do
-- this by introducing a subtype conversion.
if Do_Range_Check (Newsub)
and then Etype (Newsub) /= Styp
then
Newsub := Convert_To (Styp, Newsub);
end if;
-- Now evolve the expression for the subscript. First convert
-- the subscript to be zero based and of an integer type.
-- Case of integer type, where we just subtract to get lower bound
if Is_Integer_Type (Styp) then
-- If length of integer type is smaller than standard integer,
-- then we convert to integer first, then do the subtract
-- Integer (subscript) - Integer (Styp'First)
if Esize (Styp) < Esize (Standard_Integer) then
Newsub :=
Make_Op_Subtract (Loc,
Left_Opnd => Convert_To (Standard_Integer, Newsub),
Right_Opnd =>
Convert_To (Standard_Integer,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Styp, Loc),
Attribute_Name => Name_First)));
-- For larger integer types, subtract first, then convert to
-- integer, this deals with strange long long integer bounds.
-- Integer (subscript - Styp'First)
else
Newsub :=
Convert_To (Standard_Integer,
Make_Op_Subtract (Loc,
Left_Opnd => Newsub,
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Styp, Loc),
Attribute_Name => Name_First)));
end if;
-- For the enumeration case, we have to use 'Pos to get the value
-- to work with before subtracting the lower bound.
-- Integer (Styp'Pos (subscr)) - Integer (Styp'Pos (Styp'First));
-- This is not quite right for bizarre cases where the size of the
-- enumeration type is > Integer'Size bits due to rep clause ???
else
pragma Assert (Is_Enumeration_Type (Styp));
Newsub :=
Make_Op_Subtract (Loc,
Left_Opnd => Convert_To (Standard_Integer,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Styp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (Newsub))),
Right_Opnd =>
Convert_To (Standard_Integer,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Styp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Styp, Loc),
Attribute_Name => Name_First)))));
end if;
Set_Paren_Count (Newsub, 1);
-- For the first subscript, we just copy that subscript value
if No (Subscr) then
Subscr := Newsub;
-- Otherwise, we must multiply what we already have by the current
-- stride and then add in the new value to the evolving subscript.
else
Subscr :=
Make_Op_Add (Loc,
Left_Opnd =>
Make_Op_Multiply (Loc,
Left_Opnd => Subscr,
Right_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Range_Length,
Prefix => New_Occurrence_Of (Styp, Loc))),
Right_Opnd => Newsub);
end if;
-- Move to next subscript
Next_Index (Indx);
Next (Oldsub);
end loop;
end Compute_Linear_Subscript;
-------------------------
-- Convert_To_PAT_Type --
-------------------------
-- The PAT is always obtained from the actual subtype
procedure Convert_To_PAT_Type (Aexp : Entity_Id) is
Act_ST : Entity_Id;
begin
Convert_To_Actual_Subtype (Aexp);
Act_ST := Underlying_Type (Etype (Aexp));
Create_Packed_Array_Type (Act_ST);
-- Just replace the etype with the packed array type. This works
-- because the expression will not be further analyzed, and Gigi
-- considers the two types equivalent in any case.
Set_Etype (Aexp, Packed_Array_Type (Act_ST));
end Convert_To_PAT_Type;
------------------------------
-- Create_Packed_Array_Type --
------------------------------
procedure Create_Packed_Array_Type (Typ : Entity_Id) is
Loc : constant Source_Ptr := Sloc (Typ);
Ctyp : constant Entity_Id := Component_Type (Typ);
Csize : constant Uint := Component_Size (Typ);
Ancest : Entity_Id;
PB_Type : Entity_Id;
Esiz : Uint;
Decl : Node_Id;
PAT : Entity_Id;
Len_Dim : Node_Id;
Len_Expr : Node_Id;
Len_Bits : Uint;
Bits_U1 : Node_Id;
PAT_High : Node_Id;
Btyp : Entity_Id;
Lit : Node_Id;
procedure Install_PAT;
-- This procedure is called with Decl set to the declaration for the
-- packed array type. It creates the type and installs it as required.
procedure Set_PB_Type;
-- Sets PB_Type to Packed_Bytes{1,2,4} as required by the alignment
-- requirements (see documentation in the spec of this package).
-----------------
-- Install_PAT --
-----------------
procedure Install_PAT is
Pushed_Scope : Boolean := False;
begin
-- We do not want to put the declaration we have created in the tree
-- since it is often hard, and sometimes impossible to find a proper
-- place for it (the impossible case arises for a packed array type
-- with bounds depending on the discriminant, a declaration cannot
-- be put inside the record, and the reference to the discriminant
-- cannot be outside the record).
-- The solution is to analyze the declaration while temporarily
-- attached to the tree at an appropriate point, and then we install
-- the resulting type as an Itype in the packed array type field of
-- the original type, so that no explicit declaration is required.
-- Note: the packed type is created in the scope of its parent
-- type. There are at least some cases where the current scope
-- is deeper, and so when this is the case, we temporarily reset
-- the scope for the definition. This is clearly safe, since the
-- first use of the packed array type will be the implicit
-- reference from the corresponding unpacked type when it is
-- elaborated.
if Is_Itype (Typ) then
Set_Parent (Decl, Associated_Node_For_Itype (Typ));
else
Set_Parent (Decl, Declaration_Node (Typ));
end if;
if Scope (Typ) /= Current_Scope then
New_Scope (Scope (Typ));
Pushed_Scope := True;
end if;
Set_Is_Itype (PAT, True);
Set_Is_Packed_Array_Type (PAT, True);
Analyze (Decl, Suppress => All_Checks);
if Pushed_Scope then
Pop_Scope;
end if;
-- Set Esize and RM_Size to the actual size of the packed object
-- Do not reset RM_Size if already set, as happens in the case
-- of a modular type
Set_Esize (PAT, Esiz);
if Unknown_RM_Size (PAT) then
Set_RM_Size (PAT, Esiz);
end if;
-- Set remaining fields of packed array type
Init_Alignment (PAT);
Set_Parent (PAT, Empty);
Set_Packed_Array_Type (Typ, PAT);
Set_Associated_Node_For_Itype (PAT, Typ);
-- We definitely do not want to delay freezing for packed array
-- types. This is of particular importance for the itypes that
-- are generated for record components depending on discriminants
-- where there is no place to put the freeze node.
Set_Has_Delayed_Freeze (PAT, False);
Set_Has_Delayed_Freeze (Etype (PAT), False);
end Install_PAT;
-----------------
-- Set_PB_Type --
-----------------
procedure Set_PB_Type is
begin
-- If the user has specified an explicit alignment for the
-- component, take it into account.
if Csize <= 2 or else Csize = 4 or else Csize mod 2 /= 0
or else Component_Alignment (Typ) = Calign_Storage_Unit
then
PB_Type := RTE (RE_Packed_Bytes1);
elsif Csize mod 4 /= 0 then
PB_Type := RTE (RE_Packed_Bytes2);
else
PB_Type := RTE (RE_Packed_Bytes4);
end if;
end Set_PB_Type;
-- Start of processing for Create_Packed_Array_Type
begin
-- If we already have a packed array type, nothing to do
if Present (Packed_Array_Type (Typ)) then
return;
end if;
-- If our immediate ancestor subtype is constrained, and it already
-- has a packed array type, then just share the same type, since the
-- bounds must be the same.
if Ekind (Typ) = E_Array_Subtype then
Ancest := Ancestor_Subtype (Typ);
if Present (Ancest)
and then Is_Constrained (Ancest)
and then Present (Packed_Array_Type (Ancest))
then
Set_Packed_Array_Type (Typ, Packed_Array_Type (Ancest));
return;
end if;
end if;
-- We preset the result type size from the size of the original array
-- type, since this size clearly belongs to the packed array type. The
-- size of the conceptual unpacked type is always set to unknown.
Esiz := Esize (Typ);
-- Case of an array where at least one index is of an enumeration
-- type with a non-standard representation, but the component size
-- is not appropriate for bit packing. This is the case where we
-- have Is_Packed set (we would never be in this unit otherwise),
-- but Is_Bit_Packed_Array is false.
-- Note that if the component size is appropriate for bit packing,
-- then the circuit for the computation of the subscript properly
-- deals with the non-standard enumeration type case by taking the
-- Pos anyway.
if not Is_Bit_Packed_Array (Typ) then
-- Here we build a declaration:
-- type tttP is array (index1, index2, ...) of component_type
-- where index1, index2, are the index types. These are the same
-- as the index types of the original array, except for the non-
-- standard representation enumeration type case, where we have
-- two subcases.
-- For the unconstrained array case, we use
-- Natural range <>
-- For the constrained case, we use
-- Natural range Enum_Type'Pos (Enum_Type'First) ..
-- Enum_Type'Pos (Enum_Type'Last);
PAT :=
Make_Defining_Identifier (Loc,
Chars => New_External_Name (Chars (Typ), 'P'));
Set_Packed_Array_Type (Typ, PAT);
declare
Indexes : List_Id := New_List;
Indx : Node_Id;
Indx_Typ : Entity_Id;
Enum_Case : Boolean;
Typedef : Node_Id;
begin
Indx := First_Index (Typ);
while Present (Indx) loop
Indx_Typ := Etype (Indx);
Enum_Case := Is_Enumeration_Type (Indx_Typ)
and then Has_Non_Standard_Rep (Indx_Typ);
-- Unconstrained case
if not Is_Constrained (Typ) then
if Enum_Case then
Indx_Typ := Standard_Natural;
end if;
Append_To (Indexes, New_Occurrence_Of (Indx_Typ, Loc));
-- Constrained case
else
if not Enum_Case then
Append_To (Indexes, New_Occurrence_Of (Indx_Typ, Loc));
else
Append_To (Indexes,
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (Standard_Natural, Loc),
Constraint =>
Make_Range_Constraint (Loc,
Range_Expression =>
Make_Range (Loc,
Low_Bound =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Indx_Typ, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Indx_Typ, Loc),
Attribute_Name => Name_First))),
High_Bound =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Indx_Typ, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Indx_Typ, Loc),
Attribute_Name => Name_Last)))))));
end if;
end if;
Next_Index (Indx);
end loop;
if not Is_Constrained (Typ) then
Typedef :=
Make_Unconstrained_Array_Definition (Loc,
Subtype_Marks => Indexes,
Subtype_Indication =>
New_Occurrence_Of (Ctyp, Loc));
else
Typedef :=
Make_Constrained_Array_Definition (Loc,
Discrete_Subtype_Definitions => Indexes,
Subtype_Indication =>
New_Occurrence_Of (Ctyp, Loc));
end if;
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => PAT,
Type_Definition => Typedef);
end;
Install_PAT;
return;
-- Case of bit-packing required for unconstrained array. We simply
-- use Packed_Bytes{1,2,4} as appropriate, and we do not need to
-- construct a special packed array type.
elsif not Is_Constrained (Typ) then
Set_PB_Type;
Set_Packed_Array_Type (Typ, PB_Type);
Set_Is_Packed_Array_Type (Packed_Array_Type (Typ), True);
return;
-- Remaining code is for the case of bit-packing for constrained array
-- The name of the packed array subtype is
-- ttt___Xsss
-- where sss is the component size in bits and ttt is the name of
-- the parent packed type.
else
PAT :=
Make_Defining_Identifier (Loc,
Chars => Make_Packed_Array_Type_Name (Typ, Csize));
Set_Packed_Array_Type (Typ, PAT);
-- Build an expression for the length of the array in bits.
-- This is the product of the length of each of the dimensions
declare
J : Nat := 1;
begin
Len_Expr := Empty; -- suppress junk warning
loop
Len_Dim :=
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Length,
Prefix => New_Occurrence_Of (Typ, Loc),
Expressions => New_List (
Make_Integer_Literal (Loc, J)));
if J = 1 then
Len_Expr := Len_Dim;
else
Len_Expr :=
Make_Op_Multiply (Loc,
Left_Opnd => Len_Expr,
Right_Opnd => Len_Dim);
end if;
J := J + 1;
exit when J > Number_Dimensions (Typ);
end loop;
end;
-- Temporarily attach the length expression to the tree and analyze
-- and resolve it, so that we can test its value. We assume that the
-- total length fits in type Integer.
Set_Parent (Len_Expr, Typ);
Analyze_And_Resolve (Len_Expr, Standard_Integer);
-- Use a modular type if possible. We can do this if we are we
-- have static bounds, and the length is small enough, and the
-- length is not zero. We exclude the zero length case because the
-- size of things is always at least one, and the zero length object
-- would have an anomous size
if Compile_Time_Known_Value (Len_Expr) then
Len_Bits := Expr_Value (Len_Expr) * Csize;
-- We normally consider small enough to mean no larger than the
-- value of System_Max_Binary_Modulus_Power, except that in
-- No_Run_Time mode, we use the Word Size on machines for
-- which double length shifts are not generated in line.
if Len_Bits > 0
and then
(Len_Bits <= System_Word_Size
or else (Len_Bits <= System_Max_Binary_Modulus_Power
and then (not No_Run_Time
or else
Long_Shifts_Inlined_On_Target)))
then
-- We can use the modular type, it has the form:
-- subtype tttPn is btyp
-- range 0 .. 2 ** (Esize (Typ) * Csize) - 1;
-- Here Siz is 1, 2 or 4, as computed above, and btyp is either
-- Unsigned or Long_Long_Unsigned depending on the length.
if Len_Bits <= Standard_Integer_Size then
Btyp := RTE (RE_Unsigned);
else
Btyp := RTE (RE_Long_Long_Unsigned);
end if;
Lit := Make_Integer_Literal (Loc, 2 ** Len_Bits - 1);
Set_Print_In_Hex (Lit);
Decl :=
Make_Subtype_Declaration (Loc,
Defining_Identifier => PAT,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
Constraint =>
Make_Range_Constraint (Loc,
Range_Expression =>
Make_Range (Loc,
Low_Bound =>
Make_Integer_Literal (Loc, 0),
High_Bound => Lit))));
if Esiz = Uint_0 then
Esiz := Len_Bits;
end if;
Install_PAT;
return;
end if;
end if;
-- Could not use a modular type, for all other cases, we build
-- a packed array subtype:
-- subtype tttPn is
-- System.Packed_Bytes{1,2,4} (0 .. (Bits + 7) / 8 - 1);
-- Bits is the length of the array in bits.
Set_PB_Type;
Bits_U1 :=
Make_Op_Add (Loc,
Left_Opnd =>
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Integer_Literal (Loc, Csize),
Right_Opnd => Len_Expr),
Right_Opnd =>
Make_Integer_Literal (Loc, 7));
Set_Paren_Count (Bits_U1, 1);
PAT_High :=
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Op_Divide (Loc,
Left_Opnd => Bits_U1,
Right_Opnd => Make_Integer_Literal (Loc, 8)),
Right_Opnd => Make_Integer_Literal (Loc, 1));
Decl :=
Make_Subtype_Declaration (Loc,
Defining_Identifier => PAT,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark => New_Occurrence_Of (PB_Type, Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
Make_Range (Loc,
Low_Bound =>
Make_Integer_Literal (Loc, 0),
High_Bound => PAT_High)))));
Install_PAT;
end if;
end Create_Packed_Array_Type;
-----------------------------------
-- Expand_Bit_Packed_Element_Set --
-----------------------------------
procedure Expand_Bit_Packed_Element_Set (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Lhs : constant Node_Id := Name (N);
Ass_OK : constant Boolean := Assignment_OK (Lhs);
-- Used to preserve assignment OK status when assignment is rewritten
Rhs : Node_Id := Expression (N);
-- Initially Rhs is the right hand side value, it will be replaced
-- later by an appropriate unchecked conversion for the assignment.
Obj : Node_Id;
Atyp : Entity_Id;
PAT : Entity_Id;
Ctyp : Entity_Id;
Csiz : Int;
Shift : Node_Id;
Cmask : Uint;
New_Lhs : Node_Id;
New_Rhs : Node_Id;
Rhs_Val_Known : Boolean;
Rhs_Val : Uint;
-- If the value of the right hand side as an integer constant is
-- known at compile time, Rhs_Val_Known is set True, and Rhs_Val
-- contains the value. Otherwise Rhs_Val_Known is set False, and
-- the Rhs_Val is undefined.
begin
pragma Assert (Is_Bit_Packed_Array (Etype (Prefix (Lhs))));
Obj := Relocate_Node (Prefix (Lhs));
Convert_To_Actual_Subtype (Obj);
Atyp := Etype (Obj);
PAT := Packed_Array_Type (Atyp);
Ctyp := Component_Type (Atyp);
Csiz := UI_To_Int (Component_Size (Atyp));
-- We convert the right hand side to the proper subtype to ensure
-- that an appropriate range check is made (since the normal range
-- check from assignment will be lost in the transformations). This
-- conversion is analyzed immediately so that subsequent processing
-- can work with an analyzed Rhs (and e.g. look at its Etype)
Rhs := Convert_To (Ctyp, Rhs);
Set_Parent (Rhs, N);
Analyze_And_Resolve (Rhs, Ctyp);
-- Case of component size 1,2,4 or any component size for the modular
-- case. These are the cases for which we can inline the code.
if Csiz = 1 or else Csiz = 2 or else Csiz = 4
or else (Present (PAT) and then Is_Modular_Integer_Type (PAT))
then
Setup_Inline_Packed_Array_Reference (Lhs, Atyp, Obj, Cmask, Shift);
-- The statement to be generated is:
-- Obj := atyp!((Obj and Mask1) or (shift_left (rhs, shift)))
-- where mask1 is obtained by shifting Cmask left Shift bits
-- and then complementing the result.
-- the "and Mask1" is omitted if rhs is constant and all 1 bits
-- the "or ..." is omitted if rhs is constant and all 0 bits
-- rhs is converted to the appropriate type.
-- The result is converted back to the array type, since
-- otherwise we lose knowledge of the packed nature.
-- Determine if right side is all 0 bits or all 1 bits
if Compile_Time_Known_Value (Rhs) then
Rhs_Val := Expr_Rep_Value (Rhs);
Rhs_Val_Known := True;
-- The following test catches the case of an unchecked conversion
-- of an integer literal. This results from optimizing aggregates
-- of packed types.
elsif Nkind (Rhs) = N_Unchecked_Type_Conversion
and then Compile_Time_Known_Value (Expression (Rhs))
then
Rhs_Val := Expr_Rep_Value (Expression (Rhs));
Rhs_Val_Known := True;
else
Rhs_Val := No_Uint;
Rhs_Val_Known := False;
end if;
-- Some special checks for the case where the right hand value
-- is known at compile time. Basically we have to take care of
-- the implicit conversion to the subtype of the component object.
if Rhs_Val_Known then
-- If we have a biased component type then we must manually do
-- the biasing, since we are taking responsibility in this case
-- for constructing the exact bit pattern to be used.
if Has_Biased_Representation (Ctyp) then
Rhs_Val := Rhs_Val - Expr_Rep_Value (Type_Low_Bound (Ctyp));
end if;
-- For a negative value, we manually convert the twos complement
-- value to a corresponding unsigned value, so that the proper
-- field width is maintained. If we did not do this, we would
-- get too many leading sign bits later on.
if Rhs_Val < 0 then
Rhs_Val := 2 ** UI_From_Int (Csiz) + Rhs_Val;
end if;
end if;
New_Lhs := Duplicate_Subexpr (Obj, True);
New_Rhs := Duplicate_Subexpr (Obj);
-- First we deal with the "and"
if not Rhs_Val_Known or else Rhs_Val /= Cmask then
declare
Mask1 : Node_Id;
Lit : Node_Id;
begin
if Compile_Time_Known_Value (Shift) then
Mask1 :=
Make_Integer_Literal (Loc,
Modulus (Etype (Obj)) - 1 -
(Cmask * (2 ** Expr_Value (Shift))));
Set_Print_In_Hex (Mask1);
else
Lit := Make_Integer_Literal (Loc, Cmask);
Set_Print_In_Hex (Lit);
Mask1 :=
Make_Op_Not (Loc,
Right_Opnd => Make_Shift_Left (Lit, Shift));
end if;
New_Rhs :=
Make_Op_And (Loc,
Left_Opnd => New_Rhs,
Right_Opnd => Mask1);
end;
end if;
-- Then deal with the "or"
if not Rhs_Val_Known or else Rhs_Val /= 0 then
declare
Or_Rhs : Node_Id;
procedure Fixup_Rhs;
-- Adjust Rhs by bias if biased representation for components
-- or remove extraneous high order sign bits if signed.
procedure Fixup_Rhs is
Etyp : constant Entity_Id := Etype (Rhs);
begin
-- For biased case, do the required biasing by simply
-- converting to the biased subtype (the conversion
-- will generate the required bias).
if Has_Biased_Representation (Ctyp) then
Rhs := Convert_To (Ctyp, Rhs);
-- For a signed integer type that is not biased, generate
-- a conversion to unsigned to strip high order sign bits.
elsif Is_Signed_Integer_Type (Ctyp) then
Rhs := Unchecked_Convert_To (RTE (Bits_Id (Csiz)), Rhs);
end if;
-- Set Etype, since it can be referenced before the
-- node is completely analyzed.
Set_Etype (Rhs, Etyp);
-- We now need to do an unchecked conversion of the
-- result to the target type, but it is important that
-- this conversion be a right justified conversion and
-- not a left justified conversion.
Rhs := RJ_Unchecked_Convert_To (Etype (Obj), Rhs);
end Fixup_Rhs;
begin
if Rhs_Val_Known
and then Compile_Time_Known_Value (Shift)
then
Or_Rhs :=
Make_Integer_Literal (Loc,
Rhs_Val * (2 ** Expr_Value (Shift)));
Set_Print_In_Hex (Or_Rhs);
else
-- We have to convert the right hand side to Etype (Obj).
-- A special case case arises if what we have now is a Val
-- attribute reference whose expression type is Etype (Obj).
-- This happens for assignments of fields from the same
-- array. In this case we get the required right hand side
-- by simply removing the inner attribute reference.
if Nkind (Rhs) = N_Attribute_Reference
and then Attribute_Name (Rhs) = Name_Val
and then Etype (First (Expressions (Rhs))) = Etype (Obj)
then
Rhs := Relocate_Node (First (Expressions (Rhs)));
Fixup_Rhs;
-- If the value of the right hand side is a known integer
-- value, then just replace it by an untyped constant,
-- which will be properly retyped when we analyze and
-- resolve the expression.
elsif Rhs_Val_Known then
-- Note that Rhs_Val has already been normalized to
-- be an unsigned value with the proper number of bits.
Rhs :=
Make_Integer_Literal (Loc, Rhs_Val);
-- Otherwise we need an unchecked conversion
else
Fixup_Rhs;
end if;
Or_Rhs := Make_Shift_Left (Rhs, Shift);
end if;
if Nkind (New_Rhs) = N_Op_And then
Set_Paren_Count (New_Rhs, 1);
end if;
New_Rhs :=
Make_Op_Or (Loc,
Left_Opnd => New_Rhs,
Right_Opnd => Or_Rhs);
end;
end if;
-- Now do the rewrite
Rewrite (N,
Make_Assignment_Statement (Loc,
Name => New_Lhs,
Expression =>
Unchecked_Convert_To (Etype (New_Lhs), New_Rhs)));
Set_Assignment_OK (Name (N), Ass_OK);
-- All other component sizes for non-modular case
else
-- We generate
-- Set_nn (Arr'address, Subscr, Bits_nn!(Rhs))
-- where Subscr is the computed linear subscript.
declare
Bits_nn : constant Entity_Id := RTE (Bits_Id (Csiz));
Set_nn : Entity_Id;
Subscr : Node_Id;
Atyp : Entity_Id;
begin
-- Acquire proper Set entity. We use the aligned or unaligned
-- case as appropriate.
if Known_Aligned_Enough (Obj, Csiz) then
Set_nn := RTE (Set_Id (Csiz));
else
Set_nn := RTE (SetU_Id (Csiz));
end if;
-- Now generate the set reference
Obj := Relocate_Node (Prefix (Lhs));
Convert_To_Actual_Subtype (Obj);
Atyp := Etype (Obj);
Compute_Linear_Subscript (Atyp, Lhs, Subscr);
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Set_nn, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => Obj),
Subscr,
Unchecked_Convert_To (Bits_nn,
Convert_To (Ctyp, Rhs)))));
end;
end if;
Analyze (N, Suppress => All_Checks);
end Expand_Bit_Packed_Element_Set;
-------------------------------------
-- Expand_Packed_Address_Reference --
-------------------------------------
procedure Expand_Packed_Address_Reference (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Ploc : Source_Ptr;
Pref : Node_Id;
Expr : Node_Id;
Term : Node_Id;
Atyp : Entity_Id;
Subscr : Node_Id;
begin
Pref := Prefix (N);
Expr := Empty;
-- We build up an expression serially that has the form
-- outer_object'Address
-- + (linear-subscript * component_size for each array reference
-- + field'Bit_Position for each record field
-- + ...
-- + ...) / Storage_Unit;
-- Some additional conversions are required to deal with the addition
-- operation, which is not normally visible to generated code.
loop
Ploc := Sloc (Pref);
if Nkind (Pref) = N_Indexed_Component then
Convert_To_Actual_Subtype (Prefix (Pref));
Atyp := Etype (Prefix (Pref));
Compute_Linear_Subscript (Atyp, Pref, Subscr);
Term :=
Make_Op_Multiply (Ploc,
Left_Opnd => Subscr,
Right_Opnd =>
Make_Attribute_Reference (Ploc,
Prefix => New_Occurrence_Of (Atyp, Ploc),
Attribute_Name => Name_Component_Size));
elsif Nkind (Pref) = N_Selected_Component then
Term :=
Make_Attribute_Reference (Ploc,
Prefix => Selector_Name (Pref),
Attribute_Name => Name_Bit_Position);
else
exit;
end if;
Term := Convert_To (RTE (RE_Integer_Address), Term);
if No (Expr) then
Expr := Term;
else
Expr :=
Make_Op_Add (Ploc,
Left_Opnd => Expr,
Right_Opnd => Term);
end if;
Pref := Prefix (Pref);
end loop;
Rewrite (N,
Unchecked_Convert_To (RTE (RE_Address),
Make_Op_Add (Loc,
Left_Opnd =>
Unchecked_Convert_To (RTE (RE_Integer_Address),
Make_Attribute_Reference (Loc,
Prefix => Pref,
Attribute_Name => Name_Address)),
Right_Opnd =>
Make_Op_Divide (Loc,
Left_Opnd => Expr,
Right_Opnd =>
Make_Integer_Literal (Loc, System_Storage_Unit)))));
Analyze_And_Resolve (N, RTE (RE_Address));
end Expand_Packed_Address_Reference;
------------------------------------
-- Expand_Packed_Boolean_Operator --
------------------------------------
-- This routine expands "a op b" for the packed cases
procedure Expand_Packed_Boolean_Operator (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (N);
L : constant Node_Id := Relocate_Node (Left_Opnd (N));
R : constant Node_Id := Relocate_Node (Right_Opnd (N));
Ltyp : Entity_Id;
Rtyp : Entity_Id;
PAT : Entity_Id;
begin
Convert_To_Actual_Subtype (L);
Convert_To_Actual_Subtype (R);
Ensure_Defined (Etype (L), N);
Ensure_Defined (Etype (R), N);
Apply_Length_Check (R, Etype (L));
Ltyp := Etype (L);
Rtyp := Etype (R);
-- First an odd and silly test. We explicitly check for the XOR
-- case where the component type is True .. True, since this will
-- raise constraint error. A special check is required since CE
-- will not be required other wise (cf Expand_Packed_Not).
-- No such check is required for AND and OR, since for both these
-- cases False op False = False, and True op True = True.
if Nkind (N) = N_Op_Xor then
declare
CT : constant Entity_Id := Component_Type (Rtyp);
BT : constant Entity_Id := Base_Type (CT);
begin
Insert_Action (N,
Make_Raise_Constraint_Error (Loc,
Condition =>
Make_Op_And (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (CT, Loc),
Attribute_Name => Name_First),
Right_Opnd =>
Convert_To (BT,
New_Occurrence_Of (Standard_True, Loc))),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (CT, Loc),
Attribute_Name => Name_Last),
Right_Opnd =>
Convert_To (BT,
New_Occurrence_Of (Standard_True, Loc))))));
end;
end if;
-- Now that that silliness is taken care of, get packed array type
Convert_To_PAT_Type (L);
Convert_To_PAT_Type (R);
PAT := Etype (L);
-- For the modular case, we expand a op b into
-- rtyp!(pat!(a) op pat!(b))
-- where rtyp is the Etype of the left operand. Note that we do not
-- convert to the base type, since this would be unconstrained, and
-- hence not have a corresponding packed array type set.
if Is_Modular_Integer_Type (PAT) then
declare
P : Node_Id;
begin
if Nkind (N) = N_Op_And then
P := Make_Op_And (Loc, L, R);
elsif Nkind (N) = N_Op_Or then
P := Make_Op_Or (Loc, L, R);
else -- Nkind (N) = N_Op_Xor
P := Make_Op_Xor (Loc, L, R);
end if;
Rewrite (N, Unchecked_Convert_To (Rtyp, P));
end;
-- For the array case, we insert the actions
-- Result : Ltype;
-- System.Bitops.Bit_And/Or/Xor
-- (Left'Address,
-- Ltype'Length * Ltype'Component_Size;
-- Right'Address,
-- Rtype'Length * Rtype'Component_Size
-- Result'Address);
-- where Left and Right are the Packed_Bytes{1,2,4} operands and
-- the second argument and fourth arguments are the lengths of the
-- operands in bits. Then we replace the expression by a reference
-- to Result.
else
declare
Result_Ent : constant Entity_Id :=
Make_Defining_Identifier (Loc,
Chars => New_Internal_Name ('T'));
E_Id : RE_Id;
begin
if Nkind (N) = N_Op_And then
E_Id := RE_Bit_And;
elsif Nkind (N) = N_Op_Or then
E_Id := RE_Bit_Or;
else -- Nkind (N) = N_Op_Xor
E_Id := RE_Bit_Xor;
end if;
Insert_Actions (N, New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Result_Ent,
Object_Definition => New_Occurrence_Of (Ltyp, Loc)),
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (E_Id), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => L),
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Etype (First_Index (Ltyp)), Loc),
Attribute_Name => Name_Range_Length),
Right_Opnd =>
Make_Integer_Literal (Loc, Component_Size (Ltyp))),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => R),
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Etype (First_Index (Rtyp)), Loc),
Attribute_Name => Name_Range_Length),
Right_Opnd =>
Make_Integer_Literal (Loc, Component_Size (Rtyp))),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Occurrence_Of (Result_Ent, Loc))))));
Rewrite (N,
New_Occurrence_Of (Result_Ent, Loc));
end;
end if;
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
end Expand_Packed_Boolean_Operator;
-------------------------------------
-- Expand_Packed_Element_Reference --
-------------------------------------
procedure Expand_Packed_Element_Reference (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Obj : Node_Id;
Atyp : Entity_Id;
PAT : Entity_Id;
Ctyp : Entity_Id;
Csiz : Int;
Shift : Node_Id;
Cmask : Uint;
Lit : Node_Id;
Arg : Node_Id;
begin
-- If not bit packed, we have the enumeration case, which is easily
-- dealt with (just adjust the subscripts of the indexed component)
-- Note: this leaves the result as an indexed component, which is
-- still a variable, so can be used in the assignment case, as is
-- required in the enumeration case.
if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
Setup_Enumeration_Packed_Array_Reference (N);
return;
end if;
-- Remaining processing is for the bit-packed case.
Obj := Relocate_Node (Prefix (N));
Convert_To_Actual_Subtype (Obj);
Atyp := Etype (Obj);
PAT := Packed_Array_Type (Atyp);
Ctyp := Component_Type (Atyp);
Csiz := UI_To_Int (Component_Size (Atyp));
-- Case of component size 1,2,4 or any component size for the modular
-- case. These are the cases for which we can inline the code.
if Csiz = 1 or else Csiz = 2 or else Csiz = 4
or else (Present (PAT) and then Is_Modular_Integer_Type (PAT))
then
Setup_Inline_Packed_Array_Reference (N, Atyp, Obj, Cmask, Shift);
Lit := Make_Integer_Literal (Loc, Cmask);
Set_Print_In_Hex (Lit);
-- We generate a shift right to position the field, followed by a
-- masking operation to extract the bit field, and we finally do an
-- unchecked conversion to convert the result to the required target.
-- Note that the unchecked conversion automatically deals with the
-- bias if we are dealing with a biased representation. What will
-- happen is that we temporarily generate the biased representation,
-- but almost immediately that will be converted to the original
-- unbiased component type, and the bias will disappear.
Arg :=
Make_Op_And (Loc,
Left_Opnd => Make_Shift_Right (Obj, Shift),
Right_Opnd => Lit);
Analyze_And_Resolve (Arg);
Rewrite (N,
RJ_Unchecked_Convert_To (Ctyp, Arg));
-- All other component sizes for non-modular case
else
-- We generate
-- Component_Type!(Get_nn (Arr'address, Subscr))
-- where Subscr is the computed linear subscript.
declare
Get_nn : Entity_Id;
Subscr : Node_Id;
begin
-- Acquire proper Get entity. We use the aligned or unaligned
-- case as appropriate.
if Known_Aligned_Enough (Obj, Csiz) then
Get_nn := RTE (Get_Id (Csiz));
else
Get_nn := RTE (GetU_Id (Csiz));
end if;
-- Now generate the get reference
Compute_Linear_Subscript (Atyp, N, Subscr);
Rewrite (N,
Unchecked_Convert_To (Ctyp,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Get_nn, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => Obj),
Subscr))));
end;
end if;
Analyze_And_Resolve (N, Ctyp, Suppress => All_Checks);
end Expand_Packed_Element_Reference;
----------------------
-- Expand_Packed_Eq --
----------------------
-- Handles expansion of "=" on packed array types
procedure Expand_Packed_Eq (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
L : constant Node_Id := Relocate_Node (Left_Opnd (N));
R : constant Node_Id := Relocate_Node (Right_Opnd (N));
LLexpr : Node_Id;
RLexpr : Node_Id;
Ltyp : Entity_Id;
Rtyp : Entity_Id;
PAT : Entity_Id;
begin
Convert_To_Actual_Subtype (L);
Convert_To_Actual_Subtype (R);
Ltyp := Underlying_Type (Etype (L));
Rtyp := Underlying_Type (Etype (R));
Convert_To_PAT_Type (L);
Convert_To_PAT_Type (R);
PAT := Etype (L);
LLexpr :=
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Length,
Prefix => New_Occurrence_Of (Ltyp, Loc)),
Right_Opnd =>
Make_Integer_Literal (Loc, Component_Size (Ltyp)));
RLexpr :=
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Length,
Prefix => New_Occurrence_Of (Rtyp, Loc)),
Right_Opnd =>
Make_Integer_Literal (Loc, Component_Size (Rtyp)));
-- For the modular case, we transform the comparison to:
-- Ltyp'Length = Rtyp'Length and then PAT!(L) = PAT!(R)
-- where PAT is the packed array type. This works fine, since in the
-- modular case we guarantee that the unused bits are always zeroes.
-- We do have to compare the lengths because we could be comparing
-- two different subtypes of the same base type.
if Is_Modular_Integer_Type (PAT) then
Rewrite (N,
Make_And_Then (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => LLexpr,
Right_Opnd => RLexpr),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => L,
Right_Opnd => R)));
-- For the non-modular case, we call a runtime routine
-- System.Bit_Ops.Bit_Eq
-- (L'Address, L_Length, R'Address, R_Length)
-- where PAT is the packed array type, and the lengths are the lengths
-- in bits of the original packed arrays. This routine takes care of
-- not comparing the unused bits in the last byte.
else
Rewrite (N,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Bit_Eq), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => L),
LLexpr,
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => R),
RLexpr)));
end if;
Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
end Expand_Packed_Eq;
-----------------------
-- Expand_Packed_Not --
-----------------------
-- Handles expansion of "not" on packed array types
procedure Expand_Packed_Not (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (N);
Opnd : constant Node_Id := Relocate_Node (Right_Opnd (N));
Rtyp : Entity_Id;
PAT : Entity_Id;
Lit : Node_Id;
begin
Convert_To_Actual_Subtype (Opnd);
Rtyp := Etype (Opnd);
-- First an odd and silly test. We explicitly check for the case
-- where the 'First of the component type is equal to the 'Last of
-- this component type, and if this is the case, we make sure that
-- constraint error is raised. The reason is that the NOT is bound
-- to cause CE in this case, and we will not otherwise catch it.
-- Believe it or not, this was reported as a bug. Note that nearly
-- always, the test will evaluate statically to False, so the code
-- will be statically removed, and no extra overhead caused.
declare
CT : constant Entity_Id := Component_Type (Rtyp);
begin
Insert_Action (N,
Make_Raise_Constraint_Error (Loc,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (CT, Loc),
Attribute_Name => Name_First),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (CT, Loc),
Attribute_Name => Name_Last))));
end;
-- Now that that silliness is taken care of, get packed array type
Convert_To_PAT_Type (Opnd);
PAT := Etype (Opnd);
-- For the case where the packed array type is a modular type,
-- not A expands simply into:
-- rtyp!(PAT!(A) xor mask)
-- where PAT is the packed array type, and mask is a mask of all
-- one bits of length equal to the size of this packed type and
-- rtyp is the actual subtype of the operand
Lit := Make_Integer_Literal (Loc, 2 ** Esize (PAT) - 1);
Set_Print_In_Hex (Lit);
if not Is_Array_Type (PAT) then
Rewrite (N,
Unchecked_Convert_To (Rtyp,
Make_Op_Xor (Loc,
Left_Opnd => Opnd,
Right_Opnd => Lit)));
-- For the array case, we insert the actions
-- Result : Typ;
-- System.Bitops.Bit_Not
-- (Opnd'Address,
-- Typ'Length * Typ'Component_Size;
-- Result'Address);
-- where Opnd is the Packed_Bytes{1,2,4} operand and the second
-- argument is the length of the operand in bits. Then we replace
-- the expression by a reference to Result.
else
declare
Result_Ent : constant Entity_Id :=
Make_Defining_Identifier (Loc,
Chars => New_Internal_Name ('T'));
begin
Insert_Actions (N, New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Result_Ent,
Object_Definition => New_Occurrence_Of (Rtyp, Loc)),
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Bit_Not), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => Opnd),
Make_Op_Multiply (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Etype (First_Index (Rtyp)), Loc),
Attribute_Name => Name_Range_Length),
Right_Opnd =>
Make_Integer_Literal (Loc, Component_Size (Rtyp))),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Occurrence_Of (Result_Ent, Loc))))));
Rewrite (N,
New_Occurrence_Of (Result_Ent, Loc));
end;
end if;
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
end Expand_Packed_Not;
-------------------------------------
-- Involves_Packed_Array_Reference --
-------------------------------------
function Involves_Packed_Array_Reference (N : Node_Id) return Boolean is
begin
if Nkind (N) = N_Indexed_Component
and then Is_Bit_Packed_Array (Etype (Prefix (N)))
then
return True;
elsif Nkind (N) = N_Selected_Component then
return Involves_Packed_Array_Reference (Prefix (N));
else
return False;
end if;
end Involves_Packed_Array_Reference;
--------------------------
-- Known_Aligned_Enough --
--------------------------
function Known_Aligned_Enough (Obj : Node_Id; Csiz : Nat) return Boolean is
Typ : constant Entity_Id := Etype (Obj);
function In_Partially_Packed_Record (Comp : Entity_Id) return Boolean;
-- If the component is in a record that contains previous packed
-- components, consider it unaligned because the back-end might
-- choose to pack the rest of the record. Lead to less efficient code,
-- but safer vis-a-vis of back-end choices.
--------------------------------
-- In_Partially_Packed_Record --
--------------------------------
function In_Partially_Packed_Record (Comp : Entity_Id) return Boolean is
Rec_Type : constant Entity_Id := Scope (Comp);
Prev_Comp : Entity_Id;
begin
Prev_Comp := First_Entity (Rec_Type);
while Present (Prev_Comp) loop
if Is_Packed (Etype (Prev_Comp)) then
return True;
elsif Prev_Comp = Comp then
return False;
end if;
Next_Entity (Prev_Comp);
end loop;
return False;
end In_Partially_Packed_Record;
-- Start of processing for Known_Aligned_Enough
begin
-- Odd bit sizes don't need alignment anyway
if Csiz mod 2 = 1 then
return True;
-- If we have a specified alignment, see if it is sufficient, if not
-- then we can't possibly be aligned enough in any case.
elsif Is_Entity_Name (Obj)
and then Known_Alignment (Entity (Obj))
then
-- Alignment required is 4 if size is a multiple of 4, and
-- 2 otherwise (e.g. 12 bits requires 4, 10 bits requires 2)
if Alignment (Entity (Obj)) < 4 - (Csiz mod 4) then
return False;
end if;
end if;
-- OK, alignment should be sufficient, if object is aligned
-- If object is strictly aligned, then it is definitely aligned
if Strict_Alignment (Typ) then
return True;
-- Case of subscripted array reference
elsif Nkind (Obj) = N_Indexed_Component then
-- If we have a pointer to an array, then this is definitely
-- aligned, because pointers always point to aligned versions.
if Is_Access_Type (Etype (Prefix (Obj))) then
return True;
-- Otherwise, go look at the prefix
else
return Known_Aligned_Enough (Prefix (Obj), Csiz);
end if;
-- Case of record field
elsif Nkind (Obj) = N_Selected_Component then
-- What is significant here is whether the record type is packed
if Is_Record_Type (Etype (Prefix (Obj)))
and then Is_Packed (Etype (Prefix (Obj)))
then
return False;
-- Or the component has a component clause which might cause
-- the component to become unaligned (we can't tell if the
-- backend is doing alignment computations).
elsif Present (Component_Clause (Entity (Selector_Name (Obj)))) then
return False;
elsif In_Partially_Packed_Record (Entity (Selector_Name (Obj))) then
return False;
-- In all other cases, go look at prefix
else
return Known_Aligned_Enough (Prefix (Obj), Csiz);
end if;
-- If not selected or indexed component, must be aligned
else
return True;
end if;
end Known_Aligned_Enough;
---------------------
-- Make_Shift_Left --
---------------------
function Make_Shift_Left (N : Node_Id; S : Node_Id) return Node_Id is
Nod : Node_Id;
begin
if Compile_Time_Known_Value (S) and then Expr_Value (S) = 0 then
return N;
else
Nod :=
Make_Op_Shift_Left (Sloc (N),
Left_Opnd => N,
Right_Opnd => S);
Set_Shift_Count_OK (Nod, True);
return Nod;
end if;
end Make_Shift_Left;
----------------------
-- Make_Shift_Right --
----------------------
function Make_Shift_Right (N : Node_Id; S : Node_Id) return Node_Id is
Nod : Node_Id;
begin
if Compile_Time_Known_Value (S) and then Expr_Value (S) = 0 then
return N;
else
Nod :=
Make_Op_Shift_Right (Sloc (N),
Left_Opnd => N,
Right_Opnd => S);
Set_Shift_Count_OK (Nod, True);
return Nod;
end if;
end Make_Shift_Right;
-----------------------------
-- RJ_Unchecked_Convert_To --
-----------------------------
function RJ_Unchecked_Convert_To
(Typ : Entity_Id;
Expr : Node_Id)
return Node_Id
is
Source_Typ : constant Entity_Id := Etype (Expr);
Target_Typ : constant Entity_Id := Typ;
Src : Node_Id := Expr;
Source_Siz : Nat;
Target_Siz : Nat;
begin
Source_Siz := UI_To_Int (RM_Size (Source_Typ));
Target_Siz := UI_To_Int (RM_Size (Target_Typ));
-- In the big endian case, if the lengths of the two types differ,
-- then we must worry about possible left justification in the
-- conversion, and avoiding that is what this is all about.
if Bytes_Big_Endian and then Source_Siz /= Target_Siz then
-- First step, if the source type is not a discrete type, then we
-- first convert to a modular type of the source length, since
-- otherwise, on a big-endian machine, we get left-justification.
if not Is_Discrete_Type (Source_Typ) then
Src := Unchecked_Convert_To (RTE (Bits_Id (Source_Siz)), Src);
end if;
-- Next step. If the target is not a discrete type, then we first
-- convert to a modular type of the target length, since
-- otherwise, on a big-endian machine, we get left-justification.
if not Is_Discrete_Type (Target_Typ) then
Src := Unchecked_Convert_To (RTE (Bits_Id (Target_Siz)), Src);
end if;
end if;
-- And now we can do the final conversion to the target type
return Unchecked_Convert_To (Target_Typ, Src);
end RJ_Unchecked_Convert_To;
----------------------------------------------
-- Setup_Enumeration_Packed_Array_Reference --
----------------------------------------------
-- All we have to do here is to find the subscripts that correspond
-- to the index positions that have non-standard enumeration types
-- and insert a Pos attribute to get the proper subscript value.
-- Finally the prefix must be uncheck converted to the corresponding
-- packed array type.
-- Note that the component type is unchanged, so we do not need to
-- fiddle with the types (Gigi always automatically takes the packed
-- array type if it is set, as it will be in this case).
procedure Setup_Enumeration_Packed_Array_Reference (N : Node_Id) is
Pfx : constant Node_Id := Prefix (N);
Typ : constant Entity_Id := Etype (N);
Exprs : constant List_Id := Expressions (N);
Expr : Node_Id;
begin
-- If the array is unconstrained, then we replace the array
-- reference with its actual subtype. This actual subtype will
-- have a packed array type with appropriate bounds.
if not Is_Constrained (Packed_Array_Type (Etype (Pfx))) then
Convert_To_Actual_Subtype (Pfx);
end if;
Expr := First (Exprs);
while Present (Expr) loop
declare
Loc : constant Source_Ptr := Sloc (Expr);
Expr_Typ : constant Entity_Id := Etype (Expr);
begin
if Is_Enumeration_Type (Expr_Typ)
and then Has_Non_Standard_Rep (Expr_Typ)
then
Rewrite (Expr,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Expr_Typ, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (Relocate_Node (Expr))));
Analyze_And_Resolve (Expr, Standard_Natural);
end if;
end;
Next (Expr);
end loop;
Rewrite (N,
Make_Indexed_Component (Sloc (N),
Prefix =>
Unchecked_Convert_To (Packed_Array_Type (Etype (Pfx)), Pfx),
Expressions => Exprs));
Analyze_And_Resolve (N, Typ);
end Setup_Enumeration_Packed_Array_Reference;
-----------------------------------------
-- Setup_Inline_Packed_Array_Reference --
-----------------------------------------
procedure Setup_Inline_Packed_Array_Reference
(N : Node_Id;
Atyp : Entity_Id;
Obj : in out Node_Id;
Cmask : out Uint;
Shift : out Node_Id)
is
Loc : constant Source_Ptr := Sloc (N);
Ctyp : Entity_Id;
PAT : Entity_Id;
Otyp : Entity_Id;
Csiz : Uint;
Osiz : Uint;
begin
Ctyp := Component_Type (Atyp);
Csiz := Component_Size (Atyp);
Convert_To_PAT_Type (Obj);
PAT := Etype (Obj);
Cmask := 2 ** Csiz - 1;
if Is_Array_Type (PAT) then
Otyp := Component_Type (PAT);
Osiz := Esize (Otyp);
else
Otyp := PAT;
-- In the case where the PAT is a modular type, we want the actual
-- size in bits of the modular value we use. This is neither the
-- Object_Size nor the Value_Size, either of which may have been
-- reset to strange values, but rather the minimum size. Note that
-- since this is a modular type with full range, the issue of
-- biased representation does not arise.
Osiz := UI_From_Int (Minimum_Size (Otyp));
end if;
Compute_Linear_Subscript (Atyp, N, Shift);
-- If the component size is not 1, then the subscript must be
-- multiplied by the component size to get the shift count.
if Csiz /= 1 then
Shift :=
Make_Op_Multiply (Loc,
Left_Opnd => Make_Integer_Literal (Loc, Csiz),
Right_Opnd => Shift);
end if;
-- If we have the array case, then this shift count must be broken
-- down into a byte subscript, and a shift within the byte.
if Is_Array_Type (PAT) then
declare
New_Shift : Node_Id;
begin
-- We must analyze shift, since we will duplicate it
Set_Parent (Shift, N);
Analyze_And_Resolve
(Shift, Standard_Integer, Suppress => All_Checks);
-- The shift count within the word is
-- shift mod Osiz
New_Shift :=
Make_Op_Mod (Loc,
Left_Opnd => Duplicate_Subexpr (Shift),
Right_Opnd => Make_Integer_Literal (Loc, Osiz));
-- The subscript to be used on the PAT array is
-- shift / Osiz
Obj :=
Make_Indexed_Component (Loc,
Prefix => Obj,
Expressions => New_List (
Make_Op_Divide (Loc,
Left_Opnd => Duplicate_Subexpr (Shift),
Right_Opnd => Make_Integer_Literal (Loc, Osiz))));
Shift := New_Shift;
end;
-- For the modular integer case, the object to be manipulated is
-- the entire array, so Obj is unchanged. Note that we will reset
-- its type to PAT before returning to the caller.
else
null;
end if;
-- The one remaining step is to modify the shift count for the
-- big-endian case. Consider the following example in a byte:
-- xxxxxxxx bits of byte
-- vvvvvvvv bits of value
-- 33221100 little-endian numbering
-- 00112233 big-endian numbering
-- Here we have the case of 2-bit fields
-- For the little-endian case, we already have the proper shift
-- count set, e.g. for element 2, the shift count is 2*2 = 4.
-- For the big endian case, we have to adjust the shift count,
-- computing it as (N - F) - shift, where N is the number of bits
-- in an element of the array used to implement the packed array,
-- F is the number of bits in a source level array element, and
-- shift is the count so far computed.
if Bytes_Big_Endian then
Shift :=
Make_Op_Subtract (Loc,
Left_Opnd => Make_Integer_Literal (Loc, Osiz - Csiz),
Right_Opnd => Shift);
end if;
Set_Parent (Shift, N);
Set_Parent (Obj, N);
Analyze_And_Resolve (Obj, Otyp, Suppress => All_Checks);
Analyze_And_Resolve (Shift, Standard_Integer, Suppress => All_Checks);
-- Make sure final type of object is the appropriate packed type
Set_Etype (Obj, Otyp);
end Setup_Inline_Packed_Array_Reference;
end Exp_Pakd;