-- --
-- B o d y --
-- --
--- $Revision$
--- --
--- Copyright (C) 2001-2002 Free Software Foundation, Inc. --
+-- Copyright (C) 2001-2007, 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- --
-- 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. --
+-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
+-- Boston, MA 02110-1301, 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). --
+-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Errout; use Errout;
with Exp_Ch3; use Exp_Ch3;
with Exp_Util; use Exp_Util;
+with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
+with Opt; use Opt;
with Repinfo; use Repinfo;
with Sem; use Sem;
with Sem_Ch13; use Sem_Ch13;
-- Local Subprograms --
-----------------------
- procedure Adjust_Esize_Alignment (E : Entity_Id);
- -- E is the entity for a type or object. This procedure checks that the
- -- size and alignment are compatible, and if not either gives an error
- -- message if they cannot be adjusted or else adjusts them appropriately.
-
function Assoc_Add
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id;
+ Right_Opnd : Node_Id) return Node_Id;
-- This is like Make_Op_Add except that it optimizes some cases knowing
-- that associative rearrangement is allowed for constant folding if one
-- of the operands is a compile time known value.
function Assoc_Multiply
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id;
+ Right_Opnd : Node_Id) return Node_Id;
-- This is like Make_Op_Multiply except that it optimizes some cases
-- knowing that associative rearrangement is allowed for constant
-- folding if one of the operands is a compile time known value
function Assoc_Subtract
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id;
+ Right_Opnd : Node_Id) return Node_Id;
-- This is like Make_Op_Subtract except that it optimizes some cases
-- knowing that associative rearrangement is allowed for constant
-- folding if one of the operands is a compile time known value
+ function Bits_To_SU (N : Node_Id) return Node_Id;
+ -- This is used when we cross the boundary from static sizes in bits to
+ -- dynamic sizes in storage units. If the argument N is anything other
+ -- than an integer literal, it is returned unchanged, but if it is an
+ -- integer literal, then it is taken as a size in bits, and is replaced
+ -- by the corresponding size in storage units.
+
function Compute_Length (Lo : Node_Id; Hi : Node_Id) return Node_Id;
-- Given expressions for the low bound (Lo) and the high bound (Hi),
-- Build an expression for the value hi-lo+1, converted to type
function Expr_From_SO_Ref
(Loc : Source_Ptr;
- D : SO_Ref)
- return Node_Id;
+ D : SO_Ref;
+ Comp : Entity_Id := Empty) return Node_Id;
-- Given a value D from a size or offset field, return an expression
-- representing the value stored. If the value is known at compile time,
-- then an N_Integer_Literal is returned with the appropriate value. If
-- the value references a constant entity, then an N_Identifier node
- -- referencing this entity is returned. The Loc value is used for the
- -- Sloc value of constructed notes.
+ -- referencing this entity is returned. If the value denotes a size
+ -- function, then returns a call node denoting the given function, with
+ -- a single actual parameter that either refers to the parameter V of
+ -- an enclosing size function (if Comp is Empty or its type doesn't match
+ -- the function's formal), or else is a selected component V.c when Comp
+ -- denotes a component c whose type matches that of the function formal.
+ -- The Loc value is used for the Sloc value of constructed notes.
function SO_Ref_From_Expr
(Expr : Node_Id;
Ins_Type : Entity_Id;
- Vtype : Entity_Id := Empty)
- return Dynamic_SO_Ref;
+ Vtype : Entity_Id := Empty;
+ Make_Func : Boolean := False) return Dynamic_SO_Ref;
-- This routine is used in the case where a size/offset value is dynamic
-- and is represented by the expression Expr. SO_Ref_From_Expr checks if
-- the Expr contains a reference to the identifier V, and if so builds
-- a function depending on discriminants of the formal parameter V which
- -- is of type Vtype. If not, then a constant entity with the value Expr
- -- is built. The result is a Dynamic_SO_Ref to the created entity. Note
- -- that Vtype can be omitted if Expr does not contain any reference to V.
- -- the created entity. The declaration created is inserted in the freeze
- -- actions of Ins_Type, which also supplies the Sloc for created nodes.
- -- This function also takes care of making sure that the expression is
- -- properly analyzed and resolved (which may not be the case yet if we
- -- build the expression in this unit).
-
- function Get_Max_Size (E : Entity_Id) return Node_Id;
+ -- is of type Vtype. Otherwise, if the parameter Make_Func is True, then
+ -- Expr will be encapsulated in a parameterless function; if Make_Func is
+ -- False, then a constant entity with the value Expr is built. The result
+ -- is a Dynamic_SO_Ref to the created entity. Note that Vtype can be
+ -- omitted if Expr does not contain any reference to V, the created entity.
+ -- The declaration created is inserted in the freeze actions of Ins_Type,
+ -- which also supplies the Sloc for created nodes. This function also takes
+ -- care of making sure that the expression is properly analyzed and
+ -- resolved (which may not be the case yet if we build the expression
+ -- in this unit).
+
+ function Get_Max_SU_Size (E : Entity_Id) return Node_Id;
-- E is an array type or subtype that has at least one index bound that
-- is the value of a record discriminant. For such an array, the function
-- computes an expression that yields the maximum possible size of the
-- array in storage units. The result is not defined for any other type,
-- or for arrays that do not depend on discriminants, and it is a fatal
- -- error to call this unless Size_Depends_On_Discrminant (E) is True.
+ -- error to call this unless Size_Depends_On_Discriminant (E) is True.
procedure Layout_Array_Type (E : Entity_Id);
- -- Front end layout of non-bit-packed array type or subtype
+ -- Front-end layout of non-bit-packed array type or subtype
procedure Layout_Record_Type (E : Entity_Id);
- -- Front end layout of record type
- -- Variant records not handled yet ???
+ -- Front-end layout of record type
procedure Rewrite_Integer (N : Node_Id; V : Uint);
-- Rewrite node N with an integer literal whose value is V. The Sloc
Esize_Set := Has_Size_Clause (E);
end if;
- -- If size is known it must be a multiple of the byte size
+ -- If size is known it must be a multiple of the storage unit size
if Esize (E) mod SSU /= 0 then
if Esize_Set then
Error_Msg_NE
- ("size for& not a multiple of byte size", Size_Clause (E), E);
+ ("size for& not a multiple of storage unit size",
+ Size_Clause (E), E);
return;
- -- Otherwise bump up size to a byte boundary
+ -- Otherwise bump up size to a storage unit boundary
else
Set_Esize (E, (Esize (E) + SSU - 1) / SSU * SSU);
-- In this situation, the initial alignment of t is 4, copied from
-- the Integer base type, but it is safe to reduce it to 1 at this
- -- stage, since we will only be loading a single byte.
+ -- stage, since we will only be loading a single storage unit.
if Is_Discrete_Type (Etype (E))
and then not Has_Alignment_Clause (E)
function Assoc_Add
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id
+ Right_Opnd : Node_Id) return Node_Id
is
L : Node_Id;
R : Uint;
function Assoc_Multiply
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id
+ Right_Opnd : Node_Id) return Node_Id
is
L : Node_Id;
R : Uint;
function Assoc_Subtract
(Loc : Source_Ptr;
Left_Opnd : Node_Id;
- Right_Opnd : Node_Id)
- return Node_Id
+ Right_Opnd : Node_Id) return Node_Id
is
L : Node_Id;
R : Uint;
return Make_Op_Subtract (Loc, Left_Opnd, Right_Opnd);
end Assoc_Subtract;
+ ----------------
+ -- Bits_To_SU --
+ ----------------
+
+ function Bits_To_SU (N : Node_Id) return Node_Id is
+ begin
+ if Nkind (N) = N_Integer_Literal then
+ Set_Intval (N, (Intval (N) + (SSU - 1)) / SSU);
+ end if;
+
+ return N;
+ end Bits_To_SU;
+
--------------------
-- Compute_Length --
--------------------
function Compute_Length (Lo : Node_Id; Hi : Node_Id) return Node_Id is
- Loc : constant Source_Ptr := Sloc (Lo);
- Typ : constant Entity_Id := Etype (Lo);
- Lo_Op : Node_Id;
- Hi_Op : Node_Id;
+ Loc : constant Source_Ptr := Sloc (Lo);
+ Typ : constant Entity_Id := Etype (Lo);
+ Lo_Op : Node_Id;
+ Hi_Op : Node_Id;
+ Lo_Dim : Uint;
+ Hi_Dim : Uint;
begin
+ -- If the bounds are First and Last attributes for the same dimension
+ -- and both have prefixes that denotes the same entity, then we create
+ -- and return a Length attribute. This may allow the back end to
+ -- generate better code in cases where it already has the length.
+
+ if Nkind (Lo) = N_Attribute_Reference
+ and then Attribute_Name (Lo) = Name_First
+ and then Nkind (Hi) = N_Attribute_Reference
+ and then Attribute_Name (Hi) = Name_Last
+ and then Is_Entity_Name (Prefix (Lo))
+ and then Is_Entity_Name (Prefix (Hi))
+ and then Entity (Prefix (Lo)) = Entity (Prefix (Hi))
+ then
+ Lo_Dim := Uint_1;
+ Hi_Dim := Uint_1;
+
+ if Present (First (Expressions (Lo))) then
+ Lo_Dim := Expr_Value (First (Expressions (Lo)));
+ end if;
+
+ if Present (First (Expressions (Hi))) then
+ Hi_Dim := Expr_Value (First (Expressions (Hi)));
+ end if;
+
+ if Lo_Dim = Hi_Dim then
+ return
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Occurrence_Of
+ (Entity (Prefix (Lo)), Loc),
+ Attribute_Name => Name_Length,
+ Expressions => New_List
+ (Make_Integer_Literal (Loc, Lo_Dim)));
+ end if;
+ end if;
+
Lo_Op := New_Copy_Tree (Lo);
Hi_Op := New_Copy_Tree (Hi);
function Expr_From_SO_Ref
(Loc : Source_Ptr;
- D : SO_Ref)
- return Node_Id
+ D : SO_Ref;
+ Comp : Entity_Id := Empty) return Node_Id
is
Ent : Entity_Id;
Ent := Get_Dynamic_SO_Entity (D);
if Is_Discrim_SO_Function (Ent) then
- return
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of (Ent, Loc),
- Parameter_Associations => New_List (
- Make_Identifier (Loc, Chars => Vname)));
+ -- If a component is passed in whose type matches the type
+ -- of the function formal, then select that component from
+ -- the "V" parameter rather than passing "V" directly.
+
+ if Present (Comp)
+ and then Base_Type (Etype (Comp))
+ = Base_Type (Etype (First_Formal (Ent)))
+ then
+ return
+ Make_Function_Call (Loc,
+ Name => New_Occurrence_Of (Ent, Loc),
+ Parameter_Associations => New_List (
+ Make_Selected_Component (Loc,
+ Prefix => Make_Identifier (Loc, Chars => Vname),
+ Selector_Name => New_Occurrence_Of (Comp, Loc))));
+
+ else
+ return
+ Make_Function_Call (Loc,
+ Name => New_Occurrence_Of (Ent, Loc),
+ Parameter_Associations => New_List (
+ Make_Identifier (Loc, Chars => Vname)));
+ end if;
else
return New_Occurrence_Of (Ent, Loc);
end if;
end Expr_From_SO_Ref;
- ------------------
- -- Get_Max_Size --
- ------------------
+ ---------------------
+ -- Get_Max_SU_Size --
+ ---------------------
- function Get_Max_Size (E : Entity_Id) return Node_Id is
+ function Get_Max_SU_Size (E : Entity_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (E);
Indx : Node_Id;
Ityp : Entity_Id;
end if;
end Min_Discrim;
- -- Start of processing for Get_Max_Size
+ -- Start of processing for Get_Max_SU_Size
begin
pragma Assert (Size_Depends_On_Discriminant (E));
end loop;
-- Here after processing all bounds to set sizes. If the value is
- -- a constant, then it is bits, and we just return the value.
+ -- a constant, then it is bits, so we convert to storage units.
if Size.Status = Const then
- return Make_Integer_Literal (Loc, Size.Val);
+ return Bits_To_SU (Make_Integer_Literal (Loc, Size.Val));
-- Case where the value is dynamic
return Size.Nod;
end if;
- end Get_Max_Size;
+ end Get_Max_SU_Size;
-----------------------
-- Layout_Array_Type --
Insert_Typ : Entity_Id;
-- This is the type with which any generated constants or functions
-- will be associated (i.e. inserted into the freeze actions). This
- -- is normally the type being layed out. The exception occurs when
+ -- is normally the type being laid out. The exception occurs when
-- we are laying out Itype's which are local to a record type, and
-- whose scope is this record type. Such types do not have freeze
-- nodes (because we have no place to put them).
------------------------------------
- -- How An Array Type is Layed Out --
+ -- How An Array Type is Laid Out --
------------------------------------
-- Here is what goes on. We need to multiply the component size of
-- is the expression so far (which will be the body of the function).
Size : Val_Type;
- -- Value of size computed so far. See comments above.
+ -- Value of size computed so far. See comments above
Vtyp : Entity_Id := Empty;
-- Variant record type for the formal parameter of the
-- This is set to True if the final result must be converted from
-- bits to storage units (rounding up to a storage unit boundary).
+ Storage_Divisor : Uint := UI_From_Int (SSU);
+ -- This is the amount that a nonstatic computed size will be divided
+ -- by to convert it from bits to storage units. This is normally
+ -- equal to SSU, but can be reduced in the case of packed components
+ -- that fit evenly into a storage unit.
+
+ Make_Size_Function : Boolean := False;
+ -- Indicates whether to request that SO_Ref_From_Expr should
+ -- encapsulate the array size expresion in a function.
+
procedure Discrimify (N : in out Node_Id);
-- If N represents a discriminant, then the Size.Status is set to
-- Discrim, and Vtyp is set. The parameter N is replaced with the
-- Calculate proper type for insertions
- if Is_Record_Type (Scope (E)) then
- Insert_Typ := Scope (E);
+ if Is_Record_Type (Underlying_Type (Scope (E))) then
+ Insert_Typ := Underlying_Type (Scope (E));
else
Insert_Typ := E;
end if;
+ -- If the component type is a generic formal type then there's no point
+ -- in determining a size for the array type.
+
+ if Is_Generic_Type (Ctyp) then
+ return;
+ end if;
+
-- Deal with component size if base type
if Ekind (E) = E_Array_Type then
Indx := First_Index (E);
while Present (Indx) loop
Ityp := Etype (Indx);
+
+ -- If an index of the array is a generic formal type then there's
+ -- no point in determining a size for the array type.
+
+ if Is_Generic_Type (Ityp) then
+ return;
+ end if;
+
Lo := Type_Low_Bound (Ityp);
Hi := Type_High_Bound (Ityp);
(Dynamic, Make_Integer_Literal (Loc, Size.Val / SSU));
SU_Convert_Required := False;
+ -- If the current value is a factor of the storage unit,
+ -- then we can use a value of one for the size and reduce
+ -- the strength of the later division.
+
+ elsif SSU mod Size.Val = 0 then
+ Storage_Divisor := SSU / Size.Val;
+ Size := (Dynamic, Make_Integer_Literal (Loc, Uint_1));
+ SU_Convert_Required := True;
+
-- Otherwise, we go ahead and convert the value in bits,
-- and set SU_Convert_Required to True to ensure that the
-- final value is indeed properly converted.
Len := Compute_Length (Lo, Hi);
- -- Check possible range of Len
+ -- If Len isn't a Length attribute, then its range needs to
+ -- be checked a possible Max with zero needs to be computed.
- declare
- OK : Boolean;
- LLo : Uint;
- LHi : Uint;
+ if Nkind (Len) /= N_Attribute_Reference
+ or else Attribute_Name (Len) /= Name_Length
+ then
+ declare
+ OK : Boolean;
+ LLo : Uint;
+ LHi : Uint;
- begin
- Set_Parent (Len, E);
- Determine_Range (Len, OK, LLo, LHi);
+ begin
+ -- Check possible range of Len
- Len := Convert_To (Standard_Unsigned, Len);
+ Set_Parent (Len, E);
+ Determine_Range (Len, OK, LLo, LHi);
- -- If range definitely flat or superflat, result size is zero
+ Len := Convert_To (Standard_Unsigned, Len);
- if OK and then LHi <= 0 then
- Set_Esize (E, Uint_0);
- Set_RM_Size (E, Uint_0);
- return;
- end if;
+ -- If range definitely flat or superflat,
+ -- result size is zero
- -- If we cannot verify that range cannot be super-flat, we
- -- need a maximum with zero, since length cannot be negative.
+ if OK and then LHi <= 0 then
+ Set_Esize (E, Uint_0);
+ Set_RM_Size (E, Uint_0);
+ return;
+ end if;
- if not OK or else LLo < 0 then
- Len :=
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Occurrence_Of (Standard_Unsigned, Loc),
- Attribute_Name => Name_Max,
- Expressions => New_List (
- Make_Integer_Literal (Loc, 0),
- Len));
- end if;
- end;
+ -- If we cannot verify that range cannot be super-flat,
+ -- we need a maximum with zero, since length cannot be
+ -- negative.
+
+ if not OK or else LLo < 0 then
+ Len :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Occurrence_Of (Standard_Unsigned, Loc),
+ Attribute_Name => Name_Max,
+ Expressions => New_List (
+ Make_Integer_Literal (Loc, 0),
+ Len));
+ end if;
+ end;
+ end if;
-- At this stage, Len has the expression for the length
if SU_Convert_Required then
- -- The expression required is (Size.Nod + SU - 1) / SU
+ -- The expression required is:
+ -- (Size.Nod + Storage_Divisor - 1) / Storage_Divisor
Size.Nod :=
Make_Op_Divide (Loc,
Left_Opnd =>
Make_Op_Add (Loc,
Left_Opnd => Size.Nod,
- Right_Opnd => Make_Integer_Literal (Loc, SSU - 1)),
- Right_Opnd => Make_Integer_Literal (Loc, SSU));
+ Right_Opnd => Make_Integer_Literal
+ (Loc, Storage_Divisor - 1)),
+ Right_Opnd => Make_Integer_Literal (Loc, Storage_Divisor));
+ end if;
+
+ -- If the array entity is not declared at the library level and its
+ -- not nested within a subprogram that is marked for inlining, then
+ -- we request that the size expression be encapsulated in a function.
+ -- Since this expression is not needed in most cases, we prefer not
+ -- to incur the overhead of the computation on calls to the enclosing
+ -- subprogram except for subprograms that require the size.
+
+ if not Is_Library_Level_Entity (E) then
+ Make_Size_Function := True;
+
+ declare
+ Parent_Subp : Entity_Id := Enclosing_Subprogram (E);
+
+ begin
+ while Present (Parent_Subp) loop
+ if Is_Inlined (Parent_Subp) then
+ Make_Size_Function := False;
+ exit;
+ end if;
+
+ Parent_Subp := Enclosing_Subprogram (Parent_Subp);
+ end loop;
+ end;
end if;
-- Now set the dynamic size (the Value_Size is always the same
-- The added initialization sets it to Empty now, but is this
-- correct?
- Set_Esize (E, SO_Ref_From_Expr (Size.Nod, Insert_Typ, Vtyp));
+ Set_Esize
+ (E,
+ SO_Ref_From_Expr
+ (Size.Nod, Insert_Typ, Vtyp, Make_Func => Make_Size_Function));
Set_RM_Size (E, Esize (E));
end if;
end Layout_Array_Type;
Decl : Node_Id;
Comp : Entity_Id;
- -- Current component being layed out
+ -- Current component being laid out
Prev_Comp : Entity_Id;
- -- Previous layed out component
+ -- Previous laid out component
procedure Get_Next_Component_Location
(Prev_Comp : Entity_Id;
-- Lays out component Comp, given Prev_Comp, the previously laid-out
-- component (Prev_Comp = Empty if no components laid out yet). The
-- alignment of the record itself is also updated if needed. Both
- -- Comp and Prev_Comp can be either components or discriminants. A
- -- special case is when Comp is Empty, this is used at the end
- -- to determine the size of the entire record. For this special
- -- call the resulting offset is placed in Final_Offset.
+ -- Comp and Prev_Comp can be either components or discriminants.
procedure Layout_Components
(From : Entity_Id;
Esiz : out SO_Ref;
RM_Siz : out SO_Ref);
-- This procedure lays out the components of the given component list
- -- which contains the components starting with From, and ending with To.
- -- The Next_Entity chain is used to traverse the components. On entry
+ -- which contains the components starting with From and ending with To.
+ -- The Next_Entity chain is used to traverse the components. On entry,
-- Prev_Comp is set to the component preceding the list, so that the
- -- list is layed out after this component. Prev_Comp is set to Empty if
- -- the component list is to be layed out starting at the start of the
- -- record. On return, the components are all layed out, and Prev_Comp is
- -- set to the last layed out component. On return, Esiz is set to the
+ -- list is laid out after this component. Prev_Comp is set to Empty if
+ -- the component list is to be laid out starting at the start of the
+ -- record. On return, the components are all laid out, and Prev_Comp is
+ -- set to the last laid out component. On return, Esiz is set to the
-- resulting Object_Size value, which is the length of the record up
- -- to and including the last layed out entity. For Esiz, the value is
+ -- to and including the last laid out entity. For Esiz, the value is
-- adjusted to match the alignment of the record. RM_Siz is similarly
-- set to the resulting Value_Size value, which is the same length, but
-- not adjusted to meet the alignment. Note that in the case of variant
-- records, Esiz represents the maximum size.
procedure Layout_Non_Variant_Record;
- -- Procedure called to layout a non-variant record type or subtype
+ -- Procedure called to lay out a non-variant record type or subtype
procedure Layout_Variant_Record;
- -- Procedure called to layout a variant record type. Decl is set to the
+ -- Procedure called to lay out a variant record type. Decl is set to the
-- full type declaration for the variant record.
---------------------------------
New_Npos :=
SO_Ref_From_Expr
(Assoc_Add (Loc,
- Left_Opnd => Expr_From_SO_Ref (Loc, Old_Npos),
- Right_Opnd => Expr_From_SO_Ref (Loc, Old_Esiz)),
+ Left_Opnd =>
+ Expr_From_SO_Ref (Loc, Old_Npos),
+ Right_Opnd =>
+ Expr_From_SO_Ref (Loc, Old_Esiz, Prev_Comp)),
Ins_Type => E,
Vtype => E);
-- Get maximum size of previous component
if Size_Depends_On_Discriminant (Etype (Prev_Comp)) then
- Old_Maxsz := Get_Max_Size (Etype (Prev_Comp));
+ Old_Maxsz := Get_Max_SU_Size (Etype (Prev_Comp));
else
- Old_Maxsz := Expr_From_SO_Ref (Loc, Old_Esiz);
+ Old_Maxsz := Expr_From_SO_Ref (Loc, Old_Esiz, Prev_Comp);
end if;
-- Now we can compute the new max position. If the max size
-- Bump alignment if stricter than prev
- if Align > Alignment (Prev_Comp) then
+ if Align > Alignment (Etype (Prev_Comp)) then
New_Npos := (New_Npos + Align - 1) / Align * Align;
end if;
procedure Layout_Component (Comp : Entity_Id; Prev_Comp : Entity_Id) is
Ctyp : constant Entity_Id := Etype (Comp);
+ ORC : constant Entity_Id := Original_Record_Component (Comp);
Npos : SO_Ref;
Fbit : SO_Ref;
NPMax : SO_Ref;
Forc : Boolean;
begin
+ -- Increase alignment of record if necessary. Note that we do not
+ -- do this for packed records, which have an alignment of one by
+ -- default, or for records for which an explicit alignment was
+ -- specified with an alignment clause.
+
+ if not Is_Packed (E)
+ and then not Has_Alignment_Clause (E)
+ and then Alignment (Ctyp) > Alignment (E)
+ then
+ Set_Alignment (E, Alignment (Ctyp));
+ end if;
+
+ -- If original component set, then use same layout
+
+ if Present (ORC) and then ORC /= Comp then
+ Set_Normalized_Position (Comp, Normalized_Position (ORC));
+ Set_Normalized_First_Bit (Comp, Normalized_First_Bit (ORC));
+ Set_Normalized_Position_Max (Comp, Normalized_Position_Max (ORC));
+ Set_Component_Bit_Offset (Comp, Component_Bit_Offset (ORC));
+ Set_Esize (Comp, Esize (ORC));
+ return;
+ end if;
+
-- Parent field is always at start of record, this will overlap
-- the actual fields that are part of the parent, and that's fine
-- Check case of type of component has a scope of the record we
-- are laying out. When this happens, the type in question is an
- -- Itype that has not yet been layed out (that's because such
+ -- Itype that has not yet been laid out (that's because such
-- types do not get frozen in the normal manner, because there
-- is no place for the freeze nodes).
Layout_Type (Ctyp);
end if;
- -- Increase alignment of record if necessary. Note that we do not
- -- do this for packed records, which have an alignment of one by
- -- default, or for records for which an explicit alignment was
- -- specified with an alignment clause.
-
- if not Is_Packed (E)
- and then not Has_Alignment_Clause (E)
- and then Alignment (Ctyp) > Alignment (E)
- then
- Set_Alignment (E, Alignment (Ctyp));
- end if;
-
-- If component already laid out, then we are done
if Known_Normalized_Position (Comp) then
End_NPMax : SO_Ref;
begin
- -- Only layout components if there are some to layout!
+ -- Only lay out components if there are some to lay out!
if Present (From) then
- -- Layout components with no component clauses
+ -- Lay out components with no component clauses
Comp := From;
loop
- if (Ekind (Comp) = E_Component
- or else Ekind (Comp) = E_Discriminant)
- and then No (Component_Clause (Comp))
+ if Ekind (Comp) = E_Component
+ or else Ekind (Comp) = E_Discriminant
then
- Layout_Component (Comp, Prev_Comp);
- Prev_Comp := Comp;
+ -- The compatibility of component clauses with composite
+ -- types isn't checked in Sem_Ch13, so we check it here.
+
+ if Present (Component_Clause (Comp)) then
+ if Is_Composite_Type (Etype (Comp))
+ and then Esize (Comp) < RM_Size (Etype (Comp))
+ then
+ Error_Msg_Uint_1 := RM_Size (Etype (Comp));
+ Error_Msg_NE
+ ("size for & too small, minimum allowed is ^",
+ Component_Clause (Comp),
+ Comp);
+ end if;
+
+ else
+ Layout_Component (Comp, Prev_Comp);
+ Prev_Comp := Comp;
+ end if;
end if;
exit when Comp = To;
Esiz := Uint_0;
RM_Siz := Uint_0;
+ -- If record subtype with non-static discriminants, then we don't
+ -- know which variant will be the one which gets chosen. We don't
+ -- just want to set the maximum size from the base, because the
+ -- size should depend on the particular variant.
+
+ -- What we do is to use the RM_Size of the base type, which has
+ -- the necessary conditional computation of the size, using the
+ -- size information for the particular variant chosen. Records
+ -- with default discriminants for example have an Esize that is
+ -- set to the maximum of all variants, but that's not what we
+ -- want for a constrained subtype.
+
+ elsif Ekind (E) = E_Record_Subtype
+ and then not Has_Static_Discriminants (E)
+ then
+ declare
+ BT : constant Node_Id := Base_Type (E);
+ begin
+ Esiz := RM_Size (BT);
+ RM_Siz := RM_Size (BT);
+ Set_Alignment (E, Alignment (BT));
+ end;
+
else
- -- First the object size, for which we align past the last
- -- field to the alignment of the record (the object size
- -- is required to be a multiple of the alignment).
+ -- First the object size, for which we align past the last field
+ -- to the alignment of the record (the object size is required to
+ -- be a multiple of the alignment).
Get_Next_Component_Location
(Prev_Comp,
Force_SU => True);
-- If the resulting normalized position is a dynamic reference,
- -- then the size is dynamic, and is stored in storage units.
- -- In this case, we set the RM_Size to the same value, it is
- -- simply not worth distinguishing Esize and RM_Size values in
- -- the dynamic case, since the RM has nothing to say about them.
+ -- then the size is dynamic, and is stored in storage units. In
+ -- this case, we set the RM_Size to the same value, it is simply
+ -- not worth distinguishing Esize and RM_Size values in the
+ -- dynamic case, since the RM has nothing to say about them.
-- Note that a size cannot have been given in this case, since
-- size specifications cannot be given for variable length types.
if Is_Dynamic_SO_Ref (End_Npos) then
RM_Siz := End_Npos;
- -- Set the Object_Size allowing for alignment. In the
- -- dynamic case, we have to actually do the runtime
- -- computation. We can skip this in the non-packed
- -- record case if the last component has a smaller
- -- alignment than the overall record alignment.
+ -- Set the Object_Size allowing for the alignment. In the
+ -- dynamic case, we must do the actual runtime computation.
+ -- We can skip this in the non-packed record case if the
+ -- last component has a smaller alignment than the overall
+ -- record alignment.
if Is_Dynamic_SO_Ref (End_NPMax) then
Esiz := End_NPMax;
if Is_Packed (E)
- or else Alignment (Prev_Comp) < Align
+ or else Alignment (Etype (Prev_Comp)) < Align
then
- -- The expression we build is
- -- (expr + align - 1) / align * align
+ -- The expression we build is:
+ -- (expr + align - 1) / align * align
Esiz :=
SO_Ref_From_Expr
-- accordingly. We also adjust the size to match the
-- alignment here.
- Esiz := (End_NPMax + Align - 1) / Align * Align * SSU;
+ Esiz := (End_NPMax + Align - 1) / Align * Align * SSU;
-- Compute the resulting Value_Size (RM_Size). For this
-- purpose we do not force alignment of the record or
procedure Layout_Non_Variant_Record is
Esiz : SO_Ref;
RM_Siz : SO_Ref;
-
begin
Layout_Components (First_Entity (E), Last_Entity (E), Esiz, RM_Siz);
Set_Esize (E, Esiz);
---------------------------
procedure Layout_Variant_Record is
- Tdef : constant Node_Id := Type_Definition (Decl);
- Dlist : constant List_Id := Discriminant_Specifications (Decl);
- Esiz : SO_Ref;
- RM_Siz : SO_Ref;
+ Tdef : constant Node_Id := Type_Definition (Decl);
+ First_Discr : Entity_Id;
+ Last_Discr : Entity_Id;
+ Esiz : SO_Ref;
+ RM_Siz : SO_Ref;
RM_Siz_Expr : Node_Id := Empty;
-- Expression for the evolving RM_Siz value. This is typically a
(Clist : Node_Id;
Esiz : out SO_Ref;
RM_Siz_Expr : out Node_Id);
- -- Recursive procedure, called to layout one component list
+ -- Recursive procedure, called to lay out one component list
-- Esiz and RM_Siz_Expr are set to the Object_Size and Value_Size
-- values respectively representing the record size up to and
-- including the last component in the component list (including
if Is_Static_SO_Ref (RM_Siz) then
RM_Siz_Expr :=
Make_Integer_Literal (Loc,
- Intval => RM_Siz);
+ Intval => RM_Siz);
else
RMS_Ent := Get_Dynamic_SO_Entity (RM_Siz);
else
declare
- EsizV : SO_Ref;
- RM_SizV : Node_Id;
- Dchoice : Node_Id;
- Discrim : Node_Id;
- Dtest : Node_Id;
+ EsizV : SO_Ref;
+ RM_SizV : Node_Id;
+ Dchoice : Node_Id;
+ Discrim : Node_Id;
+ Dtest : Node_Id;
+ D_List : List_Id;
+ D_Entity : Entity_Id;
begin
RM_Siz_Expr := Empty;
-- If either value is dynamic, then we have to generate
-- an appropriate Standard_Unsigned'Max attribute call.
+ -- If one of the values is static then it needs to be
+ -- converted from bits to storage units to be compatible
+ -- with the dynamic value.
else
+ if Is_Static_SO_Ref (Esiz) then
+ Esiz := (Esiz + SSU - 1) / SSU;
+ end if;
+
+ if Is_Static_SO_Ref (EsizV) then
+ EsizV := (EsizV + SSU - 1) / SSU;
+ end if;
+
Esiz :=
SO_Ref_From_Expr
(Make_Attribute_Reference (Loc,
-- care of the others case.
if No (RM_Siz_Expr) then
- RM_Siz_Expr := RM_SizV;
+ RM_Siz_Expr := Bits_To_SU (RM_SizV);
-- Otherwise construct the appropriate test
else
- -- Discriminant to be tested
-
- Discrim :=
- Make_Selected_Component (Loc,
- Prefix =>
- Make_Identifier (Loc, Chars => Vname),
- Selector_Name =>
- New_Occurrence_Of
- (Entity (Name (Vpart)), Loc));
-
-- The test to be used in general is a call to the
-- discriminant checking function. However, it is
-- definitely worth special casing the very common
if No (Next (Dchoice))
and then Nkind (Dchoice) /= N_Range
then
+ -- Discriminant to be tested
+
+ Discrim :=
+ Make_Selected_Component (Loc,
+ Prefix =>
+ Make_Identifier (Loc, Chars => Vname),
+ Selector_Name =>
+ New_Occurrence_Of
+ (Entity (Name (Vpart)), Loc));
+
Dtest :=
Make_Op_Eq (Loc,
Left_Opnd => Discrim,
Right_Opnd => New_Copy (Dchoice));
+ -- Generate a call to the discriminant-checking
+ -- function for the variant. Note that the result
+ -- has to be complemented since the function returns
+ -- False when the passed discriminant value matches.
+
else
+ -- The checking function takes all of the type's
+ -- discriminants as parameters, so a list of all
+ -- the selected discriminants must be constructed.
+
+ D_List := New_List;
+ D_Entity := First_Discriminant (E);
+ while Present (D_Entity) loop
+ Append (
+ Make_Selected_Component (Loc,
+ Prefix =>
+ Make_Identifier (Loc, Chars => Vname),
+ Selector_Name =>
+ New_Occurrence_Of
+ (D_Entity, Loc)),
+ D_List);
+
+ D_Entity := Next_Discriminant (D_Entity);
+ end loop;
+
Dtest :=
- Make_Function_Call (Loc,
- Name =>
- New_Occurrence_Of
- (Dcheck_Function (Var), Loc),
- Parameter_Associations => New_List (Discrim));
+ Make_Op_Not (Loc,
+ Right_Opnd =>
+ Make_Function_Call (Loc,
+ Name =>
+ New_Occurrence_Of
+ (Dcheck_Function (Var), Loc),
+ Parameter_Associations =>
+ D_List));
end if;
RM_Siz_Expr :=
Make_Conditional_Expression (Loc,
Expressions =>
- New_List (Dtest, RM_SizV, RM_Siz_Expr));
+ New_List
+ (Dtest, Bits_To_SU (RM_SizV), RM_Siz_Expr));
end if;
Prev (Var);
Build_Discr_Checking_Funcs (Decl);
- -- Layout the discriminants
+ -- Lay out the discriminants
+
+ First_Discr := First_Discriminant (E);
+ Last_Discr := First_Discr;
+ while Present (Next_Discriminant (Last_Discr)) loop
+ Next_Discriminant (Last_Discr);
+ end loop;
Layout_Components
- (From => Defining_Identifier (First (Dlist)),
- To => Defining_Identifier (Last (Dlist)),
+ (From => First_Discr,
+ To => Last_Discr,
Esiz => Esiz,
RM_Siz => RM_Siz);
- -- Layout the main component list (this will make recursive calls
- -- to layout all component lists nested within variants).
+ -- Lay out the main component list (this will make recursive calls
+ -- to lay out all component lists nested within variants).
Layout_Component_List (Component_List (Tdef), Esiz, RM_Siz_Expr);
- Set_Esize (E, Esiz);
+ Set_Esize (E, Esiz);
-- If the RM_Size is a literal, set its value
-- components themselves are all shared.
if (Ekind (E) = E_Record_Subtype
- or else Ekind (E) = E_Class_Wide_Subtype)
+ or else
+ Ekind (E) = E_Class_Wide_Subtype)
and then Present (Cloned_Subtype (E))
then
Set_Esize (E, Esize (Cloned_Subtype (E)));
-- All other cases
else
- -- Initialize aligment conservatively to 1. This value will
+ -- Initialize alignment conservatively to 1. This value will
-- be increased as necessary during processing of the record.
if Unknown_Alignment (E) then
-- Initialize previous component. This is Empty unless there
-- are components which have already been laid out by component
- -- clauses. If there are such components, we start our layout of
- -- the remaining components following the last such component
+ -- clauses. If there are such components, we start our lay out of
+ -- the remaining components following the last such component.
Prev_Comp := Empty;
- Comp := First_Entity (E);
+ Comp := First_Component_Or_Discriminant (E);
while Present (Comp) loop
- if (Ekind (Comp) = E_Component
- or else Ekind (Comp) = E_Discriminant)
- and then Present (Component_Clause (Comp))
- then
+ if Present (Component_Clause (Comp)) then
if No (Prev_Comp)
or else
Component_Bit_Offset (Comp) >
end if;
end if;
- Next_Entity (Comp);
+ Next_Component_Or_Discriminant (Comp);
end loop;
-- We have two separate circuits, one for non-variant records and
if Nkind (Decl) = N_Full_Type_Declaration
and then Has_Discriminants (E)
and then Nkind (Type_Definition (Decl)) = N_Record_Definition
+ and then Present (Component_List (Type_Definition (Decl)))
and then
Present (Variant_Part (Component_List (Type_Definition (Decl))))
then
-- backend figure out what is needed (it may be some kind
-- of fat pointer, including the static link for example.
- elsif Ekind (E) = E_Access_Protected_Subprogram_Type then
+ elsif Is_Access_Protected_Subprogram_Type (E) then
null;
-- For access subtypes, copy the size information from base type
Desig := Full_View (Desig);
end if;
- if (Is_Array_Type (Desig)
+ if Is_Array_Type (Desig)
and then not Is_Constrained (Desig)
and then not Has_Completion_In_Body (Desig)
- and then not Debug_Flag_6)
+ and then not Debug_Flag_6
then
Init_Size (E, 2 * System_Address_Size);
-- Check for bad convention set
- if Convention (E) = Convention_C
- or else
- Convention (E) = Convention_CPP
+ if Warn_On_Export_Import
+ and then
+ (Convention (E) = Convention_C
+ or else
+ Convention (E) = Convention_CPP)
then
Error_Msg_N
("?this access type does not " &
end;
end if;
- Set_Prim_Alignment (E);
+ -- On VMS, reset size to 32 for convention C access type if no
+ -- explicit size clause is given and the default size is 64. Really
+ -- we do not know the size, since depending on options for the VMS
+ -- compiler, the size of a pointer type can be 32 or 64, but choosing
+ -- 32 as the default improves compatibility with legacy VMS code.
+
+ -- Note: we do not use Has_Size_Clause in the test below, because we
+ -- want to catch the case of a derived type inheriting a size clause.
+ -- We want to consider this to be an explicit size clause for this
+ -- purpose, since it would be weird not to inherit the size in this
+ -- case.
+
+ if OpenVMS_On_Target
+ and then (Convention (E) = Convention_C
+ or else
+ Convention (E) = Convention_CPP)
+ and then No (Get_Attribute_Definition_Clause (E, Attribute_Size))
+ and then Esize (E) = 64
+ then
+ Init_Size (E, 32);
+ end if;
+
+ Set_Elem_Alignment (E);
-- Scalar types: set size and alignment
-- For discrete types, the RM_Size and Esize must be set
-- already, since this is part of the earlier processing
- -- and the front end is always required to layout the
+ -- and the front end is always required to lay out the
-- sizes of such types (since they are available as static
-- attributes). All we do is to check that this rule is
-- indeed obeyed!
if Is_Discrete_Type (E) then
- -- If the RM_Size is not set, then here is where we set it.
+ -- If the RM_Size is not set, then here is where we set it
-- Note: an RM_Size of zero looks like not set here, but this
-- is a rare case, and we can simply reset it without any harm.
end if;
end if;
- Set_Prim_Alignment (E);
+ Set_Elem_Alignment (E);
- -- Non-primitive types
+ -- Non-elementary (composite) types
else
-- If RM_Size is known, set Esize if not known
declare
A : constant Uint := Alignment_In_Bits (E);
S : constant SO_Ref := RM_Size (E);
-
begin
- Set_Esize (E, (S * A + A - 1) / A);
+ Set_Esize (E, (S + A - 1) / A * A);
end;
end if;
end if;
end if;
- -- Layout array and record types if front end layout set
+ -- Lay out array and record types if front end layout set
if Frontend_Layout_On_Target then
if Is_Array_Type (E) and then not Is_Bit_Packed_Array (E) then
Layout_Array_Type (E);
- return;
elsif Is_Record_Type (E) then
Layout_Record_Type (E);
- return;
end if;
- -- Special remaining processing for record types with a known size
- -- of 16, 32, or 64 bits whose alignment is not yet set. For these
- -- types, we set a corresponding alignment matching the size if
- -- possible, or as large as possible if not.
+ -- Case of backend layout, we still do a little in the front end
+
+ else
+ -- Processing for record types
- elsif Is_Record_Type (E) and not Debug_Flag_Q then
- Set_Composite_Alignment (E);
+ if Is_Record_Type (E) then
- -- For arrays, we only do this processing for arrays that are
- -- required to be atomic. Here, we really need to have proper
- -- alignment, but for the normal case of non-atomic arrays it
- -- seems better to use the component alignment as the default.
+ -- Special remaining processing for record types with a known
+ -- size of 16, 32, or 64 bits whose alignment is not yet set.
+ -- For these types, we set a corresponding alignment matching
+ -- the size if possible, or as large as possible if not.
- elsif Is_Array_Type (E)
- and then Is_Atomic (E)
- and then not Debug_Flag_Q
- then
- Set_Composite_Alignment (E);
+ if Convention (E) = Convention_Ada
+ and then not Debug_Flag_Q
+ then
+ Set_Composite_Alignment (E);
+ end if;
+
+ -- Procressing for array types
+
+ elsif Is_Array_Type (E) then
+
+ -- For arrays that are required to be atomic, we do the same
+ -- processing as described above for short records, since we
+ -- really need to have the alignment set for the whole array.
+
+ if Is_Atomic (E) and then not Debug_Flag_Q then
+ Set_Composite_Alignment (E);
+ end if;
+
+ -- For unpacked array types, set an alignment of 1 if we know
+ -- that the component alignment is not greater than 1. The reason
+ -- we do this is to avoid unnecessary copying of slices of such
+ -- arrays when passed to subprogram parameters (see special test
+ -- in Exp_Ch6.Expand_Actuals).
+
+ if not Is_Packed (E)
+ and then Unknown_Alignment (E)
+ then
+ if Known_Static_Component_Size (E)
+ and then Component_Size (E) = 1
+ then
+ Set_Alignment (E, Uint_1);
+ end if;
+ end if;
+ end if;
+ end if;
+
+ -- Final step is to check that Esize and RM_Size are compatible
+
+ if Known_Static_Esize (E) and then Known_Static_RM_Size (E) then
+ if Esize (E) < RM_Size (E) then
+
+ -- Esize is less than RM_Size. That's not good. First we test
+ -- whether this was set deliberately with an Object_Size clause
+ -- and if so, object to the clause.
+
+ if Has_Object_Size_Clause (E) then
+ Error_Msg_Uint_1 := RM_Size (E);
+ Error_Msg_F
+ ("object size is too small, minimum allowed is ^",
+ Expression (Get_Attribute_Definition_Clause
+ (E, Attribute_Object_Size)));
+ end if;
+
+ -- Adjust Esize up to RM_Size value
+
+ declare
+ Size : constant Uint := RM_Size (E);
+
+ begin
+ Set_Esize (E, RM_Size (E));
+
+ -- 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 storage-unit addressable).
+
+ if Is_Scalar_Type (E) then
+ if Size <= System_Storage_Unit then
+ Init_Esize (E, System_Storage_Unit);
+ elsif Size <= 16 then
+ Init_Esize (E, 16);
+ elsif Size <= 32 then
+ Init_Esize (E, 32);
+ else
+ Set_Esize (E, (Size + 63) / 64 * 64);
+ end if;
+
+ -- Finally, make sure that alignment is consistent with
+ -- the newly assigned size.
+
+ while Alignment (E) * System_Storage_Unit < Esize (E)
+ and then Alignment (E) < Maximum_Alignment
+ loop
+ Set_Alignment (E, 2 * Alignment (E));
+ end loop;
+ end if;
+ end;
+ end if;
end if;
end Layout_Type;
-- Size is known, alignment is not set
- if Siz = System_Storage_Unit then
- Align := 1;
- elsif Siz = 2 * System_Storage_Unit then
+ -- Reset alignment to match size if size is exactly 2, 4, or 8
+ -- storage units.
+
+ if Siz = 2 * System_Storage_Unit then
Align := 2;
elsif Siz = 4 * System_Storage_Unit then
Align := 4;
elsif Siz = 8 * System_Storage_Unit then
Align := 8;
+
+ -- On VMS, also reset for odd "in between" sizes, e.g. a 17-bit
+ -- record is given an alignment of 4. This is more consistent with
+ -- what DEC Ada does.
+
+ elsif OpenVMS_On_Target and then Siz > System_Storage_Unit then
+
+ if Siz <= 2 * System_Storage_Unit then
+ Align := 2;
+ elsif Siz <= 4 * System_Storage_Unit then
+ Align := 4;
+ elsif Siz <= 8 * System_Storage_Unit then
+ Align := 8;
+ else
+ return;
+ end if;
+
+ -- No special alignment fiddling needed
+
else
return;
end if;
+ -- Here Align is set to the proposed improved alignment
+
if Align > Maximum_Alignment then
Align := Maximum_Alignment;
end if;
- if Align > System_Word_Size / System_Storage_Unit then
- Align := System_Word_Size / System_Storage_Unit;
+ -- Further processing for record types only to reduce the alignment
+ -- set by the above processing in some specific cases. We do not
+ -- do this for atomic records, since we need max alignment there.
+
+ if Is_Record_Type (E) then
+
+ -- For records, there is generally no point in setting alignment
+ -- higher than word size since we cannot do better than move by
+ -- words in any case
+
+ if Align > System_Word_Size / System_Storage_Unit then
+ Align := System_Word_Size / System_Storage_Unit;
+ end if;
+
+ -- Check components. If any component requires a higher
+ -- alignment, then we set that higher alignment in any case.
+
+ declare
+ Comp : Entity_Id;
+
+ begin
+ Comp := First_Component (E);
+ while Present (Comp) loop
+ if Known_Alignment (Etype (Comp)) then
+ declare
+ Calign : constant Uint := Alignment (Etype (Comp));
+
+ begin
+ -- The cases to worry about are when the alignment
+ -- of the component type is larger than the alignment
+ -- we have so far, and either there is no component
+ -- clause for the alignment, or the length set by
+ -- the component clause matches the alignment set.
+
+ if Calign > Align
+ and then
+ (Unknown_Esize (Comp)
+ or else (Known_Static_Esize (Comp)
+ and then
+ Esize (Comp) =
+ Calign * System_Storage_Unit))
+ then
+ Align := UI_To_Int (Calign);
+ end if;
+ end;
+ end if;
+
+ Next_Component (Comp);
+ end loop;
+ end;
end if;
+ -- Set chosen alignment
+
Set_Alignment (E, UI_From_Int (Align));
- if Unknown_Esize (E) then
+ if Known_Static_Esize (E)
+ and then Esize (E) < Align * System_Storage_Unit
+ then
Set_Esize (E, UI_From_Int (Align * System_Storage_Unit));
end if;
end if;
end Set_Discrete_RM_Size;
------------------------
- -- Set_Prim_Alignment --
+ -- Set_Elem_Alignment --
------------------------
- procedure Set_Prim_Alignment (E : Entity_Id) is
+ procedure Set_Elem_Alignment (E : Entity_Id) is
begin
-- Do not set alignment for packed array types, unless we are doing
-- front end layout, because otherwise this is always handled in the
return;
-- If the size is not set, then don't attempt to set the alignment. This
- -- happens in the backend layout case for access to subprogram types.
+ -- happens in the backend layout case for access-to-subprogram types.
elsif not Known_Static_Esize (E) then
return;
Init_Alignment (E, A);
end if;
end;
- end Set_Prim_Alignment;
+ end Set_Elem_Alignment;
----------------------
-- SO_Ref_From_Expr --
function SO_Ref_From_Expr
(Expr : Node_Id;
Ins_Type : Entity_Id;
- Vtype : Entity_Id := Empty)
- return Dynamic_SO_Ref
+ Vtype : Entity_Id := Empty;
+ Make_Func : Boolean := False) return Dynamic_SO_Ref
is
Loc : constant Source_Ptr := Sloc (Ins_Type);
Decl : Node_Id;
+ Vtype_Primary_View : Entity_Id;
+
function Check_Node_V_Ref (N : Node_Id) return Traverse_Result;
-- Function used to check one node for reference to V
if Has_V_Ref (Expr) = Abandon then
pragma Assert (Present (Vtype));
+
+ -- Check whether Vtype is a view of a private type and ensure that
+ -- we use the primary view of the type (which is denoted by its
+ -- Etype, whether it's the type's partial or full view entity).
+ -- This is needed to make sure that we use the same (primary) view
+ -- of the type for all V formals, whether the current view of the
+ -- type is the partial or full view, so that types will always
+ -- match on calls from one size function to another.
+
+ if Has_Private_Declaration (Vtype) then
+ Vtype_Primary_View := Etype (Vtype);
+ else
+ Vtype_Primary_View := Vtype;
+ end if;
+
Set_Is_Discrim_SO_Function (K);
Decl :=
Defining_Identifier =>
Make_Defining_Identifier (Loc, Chars => Vname),
Parameter_Type =>
- New_Occurrence_Of (Vtype, Loc))),
- Subtype_Mark =>
+ New_Occurrence_Of (Vtype_Primary_View, Loc))),
+ Result_Definition =>
New_Occurrence_Of (Standard_Unsigned, Loc)),
Declarations => Empty_List,
Make_Return_Statement (Loc,
Expression => Expr))));
- -- No reference to V, create constant
+ -- The caller requests that the expression be encapsulated in
+ -- a parameterless function.
+
+ elsif Make_Func then
+ Decl :=
+ Make_Subprogram_Body (Loc,
+
+ Specification =>
+ Make_Function_Specification (Loc,
+ Defining_Unit_Name => K,
+ Parameter_Specifications => Empty_List,
+ Result_Definition =>
+ New_Occurrence_Of (Standard_Unsigned, Loc)),
+
+ Declarations => Empty_List,
+
+ Handled_Statement_Sequence =>
+ Make_Handled_Sequence_Of_Statements (Loc,
+ Statements => New_List (
+ Make_Return_Statement (Loc, Expression => Expr))));
+
+ -- No reference to V and function not requested, so create a constant
else
Decl :=
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