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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ I N T R --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2013, 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 3, 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 COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Checks; use Checks;
with Einfo; use Einfo;
with Elists; use Elists;
with Errout; use Errout;
with Exp_Atag; use Exp_Atag;
with Exp_Ch4; use Exp_Ch4;
with Exp_Ch7; use Exp_Ch7;
with Exp_Ch11; use Exp_Ch11;
with Exp_Code; use Exp_Code;
with Exp_Fixd; use Exp_Fixd;
with Exp_Util; use Exp_Util;
with Freeze; use Freeze;
with Namet; use Namet;
with Nmake; use Nmake;
with Nlists; use Nlists;
with Opt; use Opt;
with Restrict; use Restrict;
with Rident; use Rident;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Aux; use Sem_Aux;
with Sem_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Type; use Sem_Type;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Sinput; use Sinput;
with Snames; use Snames;
with Stand; use Stand;
with Stringt; use Stringt;
with Targparm; use Targparm;
with Tbuild; use Tbuild;
with Uintp; use Uintp;
with Urealp; use Urealp;
package body Exp_Intr is
-----------------------
-- Local Subprograms --
-----------------------
procedure Expand_Binary_Operator_Call (N : Node_Id);
-- Expand a call to an intrinsic arithmetic operator when the operand
-- types or sizes are not identical.
procedure Expand_Is_Negative (N : Node_Id);
-- Expand a call to the intrinsic Is_Negative function
procedure Expand_Dispatching_Constructor_Call (N : Node_Id);
-- Expand a call to an instantiation of Generic_Dispatching_Constructor
-- into a dispatching call to the actual subprogram associated with the
-- Constructor formal subprogram, passing it the Parameters actual of
-- the call to the instantiation and dispatching based on call's Tag
-- parameter.
procedure Expand_Exception_Call (N : Node_Id; Ent : RE_Id);
-- Expand a call to Exception_Information/Message/Name. The first
-- parameter, N, is the node for the function call, and Ent is the
-- entity for the corresponding routine in the Ada.Exceptions package.
procedure Expand_Import_Call (N : Node_Id);
-- Expand a call to Import_Address/Longest_Integer/Value. The parameter
-- N is the node for the function call.
procedure Expand_Shift (N : Node_Id; E : Entity_Id; K : Node_Kind);
-- Expand an intrinsic shift operation, N and E are from the call to
-- Expand_Intrinsic_Call (call node and subprogram spec entity) and
-- K is the kind for the shift node
procedure Expand_Unc_Conversion (N : Node_Id; E : Entity_Id);
-- Expand a call to an instantiation of Unchecked_Conversion into a node
-- N_Unchecked_Type_Conversion.
procedure Expand_Unc_Deallocation (N : Node_Id);
-- Expand a call to an instantiation of Unchecked_Deallocation into a node
-- N_Free_Statement and appropriate context.
procedure Expand_To_Address (N : Node_Id);
procedure Expand_To_Pointer (N : Node_Id);
-- Expand a call to corresponding function, declared in an instance of
-- System.Address_To_Access_Conversions.
procedure Expand_Source_Info (N : Node_Id; Nam : Name_Id);
-- Rewrite the node by the appropriate string or positive constant.
-- Nam can be one of the following:
-- Name_File - expand string that is the name of source file
-- Name_Line - expand integer line number
-- Name_Source_Location - expand string of form file:line
-- Name_Enclosing_Entity - expand string with name of enclosing entity
---------------------------------
-- Expand_Binary_Operator_Call --
---------------------------------
procedure Expand_Binary_Operator_Call (N : Node_Id) is
T1 : constant Entity_Id := Underlying_Type (Etype (Left_Opnd (N)));
T2 : constant Entity_Id := Underlying_Type (Etype (Right_Opnd (N)));
TR : constant Entity_Id := Etype (N);
T3 : Entity_Id;
Res : Node_Id;
Siz : constant Uint := UI_Max (RM_Size (T1), RM_Size (T2));
-- Maximum of operand sizes
begin
-- Nothing to do if the operands have the same modular type
if Base_Type (T1) = Base_Type (T2)
and then Is_Modular_Integer_Type (T1)
then
return;
end if;
-- Use Unsigned_32 for sizes of 32 or below, else Unsigned_64
if Siz > 32 then
T3 := RTE (RE_Unsigned_64);
else
T3 := RTE (RE_Unsigned_32);
end if;
-- Copy operator node, and reset type and entity fields, for
-- subsequent reanalysis.
Res := New_Copy (N);
Set_Etype (Res, T3);
case Nkind (N) is
when N_Op_And =>
Set_Entity (Res, Standard_Op_And);
when N_Op_Or =>
Set_Entity (Res, Standard_Op_Or);
when N_Op_Xor =>
Set_Entity (Res, Standard_Op_Xor);
when others =>
raise Program_Error;
end case;
-- Convert operands to large enough intermediate type
Set_Left_Opnd (Res,
Unchecked_Convert_To (T3, Relocate_Node (Left_Opnd (N))));
Set_Right_Opnd (Res,
Unchecked_Convert_To (T3, Relocate_Node (Right_Opnd (N))));
-- Analyze and resolve result formed by conversion to target type
Rewrite (N, Unchecked_Convert_To (TR, Res));
Analyze_And_Resolve (N, TR);
end Expand_Binary_Operator_Call;
-----------------------------------------
-- Expand_Dispatching_Constructor_Call --
-----------------------------------------
-- Transform a call to an instantiation of Generic_Dispatching_Constructor
-- of the form:
-- GDC_Instance (The_Tag, Parameters'Access)
-- to a class-wide conversion of a dispatching call to the actual
-- associated with the formal subprogram Construct, designating The_Tag
-- as the controlling tag of the call:
-- T'Class (Construct'Actual (Params)) -- Controlling tag is The_Tag
-- which will eventually be expanded to the following:
-- T'Class (The_Tag.all (Construct'Actual'Index).all (Params))
-- A class-wide membership test is also generated, preceding the call, to
-- ensure that the controlling tag denotes a type in T'Class.
procedure Expand_Dispatching_Constructor_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Tag_Arg : constant Node_Id := First_Actual (N);
Param_Arg : constant Node_Id := Next_Actual (Tag_Arg);
Subp_Decl : constant Node_Id := Parent (Parent (Entity (Name (N))));
Inst_Pkg : constant Node_Id := Parent (Subp_Decl);
Act_Rename : Node_Id;
Act_Constr : Entity_Id;
Iface_Tag : Node_Id := Empty;
Cnstr_Call : Node_Id;
Result_Typ : Entity_Id;
begin
-- Remove side effects from tag argument early, before rewriting
-- the dispatching constructor call, as Remove_Side_Effects relies
-- on Tag_Arg's Parent link properly attached to the tree (once the
-- call is rewritten, the Parent is inconsistent as it points to the
-- rewritten node, which is not the syntactic parent of the Tag_Arg
-- anymore).
Remove_Side_Effects (Tag_Arg);
-- The subprogram is the third actual in the instantiation, and is
-- retrieved from the corresponding renaming declaration. However,
-- freeze nodes may appear before, so we retrieve the declaration
-- with an explicit loop.
Act_Rename := First (Visible_Declarations (Inst_Pkg));
while Nkind (Act_Rename) /= N_Subprogram_Renaming_Declaration loop
Next (Act_Rename);
end loop;
Act_Constr := Entity (Name (Act_Rename));
Result_Typ := Class_Wide_Type (Etype (Act_Constr));
if Is_Interface (Etype (Act_Constr)) then
-- If the result type is not known to be a parent of Tag_Arg then we
-- need to locate the tag of the secondary dispatch table.
if not Is_Ancestor (Etype (Result_Typ), Etype (Tag_Arg),
Use_Full_View => True)
and then Tagged_Type_Expansion
then
-- Obtain the reference to the Ada.Tags service before generating
-- the Object_Declaration node to ensure that if this service is
-- not available in the runtime then we generate a clear error.
declare
Fname : constant Node_Id :=
New_Reference_To (RTE (RE_Secondary_Tag), Loc);
begin
pragma Assert (not Is_Interface (Etype (Tag_Arg)));
Iface_Tag :=
Make_Object_Declaration (Loc,
Defining_Identifier => Make_Temporary (Loc, 'V'),
Object_Definition =>
New_Reference_To (RTE (RE_Tag), Loc),
Expression =>
Make_Function_Call (Loc,
Name => Fname,
Parameter_Associations => New_List (
Relocate_Node (Tag_Arg),
New_Reference_To
(Node (First_Elmt (Access_Disp_Table
(Etype (Etype (Act_Constr))))),
Loc))));
Insert_Action (N, Iface_Tag);
end;
end if;
end if;
-- Create the call to the actual Constructor function
Cnstr_Call :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Act_Constr, Loc),
Parameter_Associations => New_List (Relocate_Node (Param_Arg)));
-- Establish its controlling tag from the tag passed to the instance
-- The tag may be given by a function call, in which case a temporary
-- should be generated now, to prevent out-of-order insertions during
-- the expansion of that call when stack-checking is enabled.
if Present (Iface_Tag) then
Set_Controlling_Argument (Cnstr_Call,
New_Occurrence_Of (Defining_Identifier (Iface_Tag), Loc));
else
Set_Controlling_Argument (Cnstr_Call,
Relocate_Node (Tag_Arg));
end if;
-- Rewrite and analyze the call to the instance as a class-wide
-- conversion of the call to the actual constructor.
Rewrite (N, Convert_To (Result_Typ, Cnstr_Call));
Analyze_And_Resolve (N, Etype (Act_Constr));
-- Do not generate a run-time check on the built object if tag
-- checks are suppressed for the result type or VM_Target /= No_VM
if Tag_Checks_Suppressed (Etype (Result_Typ))
or else not Tagged_Type_Expansion
then
null;
-- Generate a class-wide membership test to ensure that the call's tag
-- argument denotes a type within the class. We must keep separate the
-- case in which the Result_Type of the constructor function is a tagged
-- type from the case in which it is an abstract interface because the
-- run-time subprogram required to check these cases differ (and have
-- one difference in their parameters profile).
-- Call CW_Membership if the Result_Type is a tagged type to look for
-- the tag in the table of ancestor tags.
elsif not Is_Interface (Result_Typ) then
declare
Obj_Tag_Node : Node_Id := New_Copy_Tree (Tag_Arg);
CW_Test_Node : Node_Id;
begin
Build_CW_Membership (Loc,
Obj_Tag_Node => Obj_Tag_Node,
Typ_Tag_Node =>
New_Reference_To (
Node (First_Elmt (Access_Disp_Table (
Root_Type (Result_Typ)))), Loc),
Related_Nod => N,
New_Node => CW_Test_Node);
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc, CW_Test_Node),
Then_Statements =>
New_List (Make_Raise_Statement (Loc,
New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
end;
-- Call IW_Membership test if the Result_Type is an abstract interface
-- to look for the tag in the table of interface tags.
else
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Copy_Tree (Tag_Arg),
Attribute_Name => Name_Address),
New_Reference_To (
Node (First_Elmt (Access_Disp_Table (
Root_Type (Result_Typ)))), Loc)))),
Then_Statements =>
New_List (
Make_Raise_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
end if;
end Expand_Dispatching_Constructor_Call;
---------------------------
-- Expand_Exception_Call --
---------------------------
-- If the function call is not within an exception handler, then the call
-- is replaced by a null string. Otherwise the appropriate routine in
-- Ada.Exceptions is called passing the choice parameter specification
-- from the enclosing handler. If the enclosing handler lacks a choice
-- parameter, then one is supplied.
procedure Expand_Exception_Call (N : Node_Id; Ent : RE_Id) is
Loc : constant Source_Ptr := Sloc (N);
P : Node_Id;
E : Entity_Id;
begin
-- Climb up parents to see if we are in exception handler
P := Parent (N);
loop
-- Case of not in exception handler, replace by null string
if No (P) then
Rewrite (N,
Make_String_Literal (Loc,
Strval => ""));
exit;
-- Case of in exception handler
elsif Nkind (P) = N_Exception_Handler then
-- Handler cannot be used for a local raise, and furthermore, this
-- is a violation of the No_Exception_Propagation restriction.
Set_Local_Raise_Not_OK (P);
Check_Restriction (No_Exception_Propagation, N);
-- If no choice parameter present, then put one there. Note that
-- we do not need to put it on the entity chain, since no one will
-- be referencing it by normal visibility methods.
if No (Choice_Parameter (P)) then
E := Make_Temporary (Loc, 'E');
Set_Choice_Parameter (P, E);
Set_Ekind (E, E_Variable);
Set_Etype (E, RTE (RE_Exception_Occurrence));
Set_Scope (E, Current_Scope);
end if;
Rewrite (N,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (Ent), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Choice_Parameter (P), Loc))));
exit;
-- Keep climbing!
else
P := Parent (P);
end if;
end loop;
Analyze_And_Resolve (N, Standard_String);
end Expand_Exception_Call;
------------------------
-- Expand_Import_Call --
------------------------
-- The function call must have a static string as its argument. We create
-- a dummy variable which uses this string as the external name in an
-- Import pragma. The result is then obtained as the address of this
-- dummy variable, converted to the appropriate target type.
procedure Expand_Import_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Ent : constant Entity_Id := Entity (Name (N));
Str : constant Node_Id := First_Actual (N);
Dum : constant Entity_Id := Make_Temporary (Loc, 'D');
begin
Insert_Actions (N, New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Dum,
Object_Definition =>
New_Occurrence_Of (Standard_Character, Loc)),
Make_Pragma (Loc,
Chars => Name_Import,
Pragma_Argument_Associations => New_List (
Make_Pragma_Argument_Association (Loc,
Expression => Make_Identifier (Loc, Name_Ada)),
Make_Pragma_Argument_Association (Loc,
Expression => Make_Identifier (Loc, Chars (Dum))),
Make_Pragma_Argument_Association (Loc,
Chars => Name_Link_Name,
Expression => Relocate_Node (Str))))));
Rewrite (N,
Unchecked_Convert_To (Etype (Ent),
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Chars (Dum)),
Attribute_Name => Name_Address)));
Analyze_And_Resolve (N, Etype (Ent));
end Expand_Import_Call;
---------------------------
-- Expand_Intrinsic_Call --
---------------------------
procedure Expand_Intrinsic_Call (N : Node_Id; E : Entity_Id) is
Nam : Name_Id;
begin
-- If an external name is specified for the intrinsic, it is handled
-- by the back-end: leave the call node unchanged for now.
if Present (Interface_Name (E)) then
return;
end if;
-- If the intrinsic subprogram is generic, gets its original name
if Present (Parent (E))
and then Present (Generic_Parent (Parent (E)))
then
Nam := Chars (Generic_Parent (Parent (E)));
else
Nam := Chars (E);
end if;
if Nam = Name_Asm then
Expand_Asm_Call (N);
elsif Nam = Name_Divide then
Expand_Decimal_Divide_Call (N);
elsif Nam = Name_Exception_Information then
Expand_Exception_Call (N, RE_Exception_Information);
elsif Nam = Name_Exception_Message then
Expand_Exception_Call (N, RE_Exception_Message);
elsif Nam = Name_Exception_Name then
Expand_Exception_Call (N, RE_Exception_Name_Simple);
elsif Nam = Name_Generic_Dispatching_Constructor then
Expand_Dispatching_Constructor_Call (N);
elsif Nam = Name_Import_Address
or else
Nam = Name_Import_Largest_Value
or else
Nam = Name_Import_Value
then
Expand_Import_Call (N);
elsif Nam = Name_Is_Negative then
Expand_Is_Negative (N);
elsif Nam = Name_Rotate_Left then
Expand_Shift (N, E, N_Op_Rotate_Left);
elsif Nam = Name_Rotate_Right then
Expand_Shift (N, E, N_Op_Rotate_Right);
elsif Nam = Name_Shift_Left then
Expand_Shift (N, E, N_Op_Shift_Left);
elsif Nam = Name_Shift_Right then
Expand_Shift (N, E, N_Op_Shift_Right);
elsif Nam = Name_Shift_Right_Arithmetic then
Expand_Shift (N, E, N_Op_Shift_Right_Arithmetic);
elsif Nam = Name_Unchecked_Conversion then
Expand_Unc_Conversion (N, E);
elsif Nam = Name_Unchecked_Deallocation then
Expand_Unc_Deallocation (N);
elsif Nam = Name_To_Address then
Expand_To_Address (N);
elsif Nam = Name_To_Pointer then
Expand_To_Pointer (N);
elsif Nam = Name_File
or else Nam = Name_Line
or else Nam = Name_Source_Location
or else Nam = Name_Enclosing_Entity
then
Expand_Source_Info (N, Nam);
-- If we have a renaming, expand the call to the original operation,
-- which must itself be intrinsic, since renaming requires matching
-- conventions and this has already been checked.
elsif Present (Alias (E)) then
Expand_Intrinsic_Call (N, Alias (E));
elsif Nkind (N) in N_Binary_Op then
Expand_Binary_Operator_Call (N);
-- The only other case is where an external name was specified, since
-- this is the only way that an otherwise unrecognized name could
-- escape the checking in Sem_Prag. Nothing needs to be done in such
-- a case, since we pass such a call to the back end unchanged.
else
null;
end if;
end Expand_Intrinsic_Call;
------------------------
-- Expand_Is_Negative --
------------------------
procedure Expand_Is_Negative (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Opnd : constant Node_Id := Relocate_Node (First_Actual (N));
begin
-- We replace the function call by the following expression
-- if Opnd < 0.0 then
-- True
-- else
-- if Opnd > 0.0 then
-- False;
-- else
-- Float_Unsigned!(Float (Opnd)) /= 0
-- end if;
-- end if;
Rewrite (N,
Make_If_Expression (Loc,
Expressions => New_List (
Make_Op_Lt (Loc,
Left_Opnd => Duplicate_Subexpr (Opnd),
Right_Opnd => Make_Real_Literal (Loc, Ureal_0)),
New_Occurrence_Of (Standard_True, Loc),
Make_If_Expression (Loc,
Expressions => New_List (
Make_Op_Gt (Loc,
Left_Opnd => Duplicate_Subexpr_No_Checks (Opnd),
Right_Opnd => Make_Real_Literal (Loc, Ureal_0)),
New_Occurrence_Of (Standard_False, Loc),
Make_Op_Ne (Loc,
Left_Opnd =>
Unchecked_Convert_To
(RTE (RE_Float_Unsigned),
Convert_To
(Standard_Float,
Duplicate_Subexpr_No_Checks (Opnd))),
Right_Opnd =>
Make_Integer_Literal (Loc, 0)))))));
Analyze_And_Resolve (N, Standard_Boolean);
end Expand_Is_Negative;
------------------
-- Expand_Shift --
------------------
-- This procedure is used to convert a call to a shift function to the
-- corresponding operator node. This conversion is not done by the usual
-- circuit for converting calls to operator functions (e.g. "+"(1,2)) to
-- operator nodes, because shifts are not predefined operators.
-- As a result, whenever a shift is used in the source program, it will
-- remain as a call until converted by this routine to the operator node
-- form which Gigi is expecting to see.
-- Note: it is possible for the expander to generate shift operator nodes
-- directly, which will be analyzed in the normal manner by calling Analyze
-- and Resolve. Such shift operator nodes will not be seen by Expand_Shift.
procedure Expand_Shift (N : Node_Id; E : Entity_Id; K : Node_Kind) is
Entyp : constant Entity_Id := Etype (E);
Left : constant Node_Id := First_Actual (N);
Loc : constant Source_Ptr := Sloc (N);
Right : constant Node_Id := Next_Actual (Left);
Ltyp : constant Node_Id := Etype (Left);
Rtyp : constant Node_Id := Etype (Right);
Typ : constant Entity_Id := Etype (N);
Snode : Node_Id;
begin
Snode := New_Node (K, Loc);
Set_Right_Opnd (Snode, Relocate_Node (Right));
Set_Chars (Snode, Chars (E));
Set_Etype (Snode, Base_Type (Entyp));
Set_Entity (Snode, E);
if Compile_Time_Known_Value (Type_High_Bound (Rtyp))
and then Expr_Value (Type_High_Bound (Rtyp)) < Esize (Ltyp)
then
Set_Shift_Count_OK (Snode, True);
end if;
if Typ = Entyp then
-- Note that we don't call Analyze and Resolve on this node, because
-- it already got analyzed and resolved when it was a function call.
Set_Left_Opnd (Snode, Relocate_Node (Left));
Rewrite (N, Snode);
Set_Analyzed (N);
else
-- If the context type is not the type of the operator, it is an
-- inherited operator for a derived type. Wrap the node in a
-- conversion so that it is type-consistent for possible further
-- expansion (e.g. within a lock-free protected type).
Set_Left_Opnd (Snode,
Unchecked_Convert_To (Base_Type (Entyp), Relocate_Node (Left)));
Rewrite (N, Unchecked_Convert_To (Typ, Snode));
-- Analyze and resolve result formed by conversion to target type
Analyze_And_Resolve (N, Typ);
end if;
end Expand_Shift;
------------------------
-- Expand_Source_Info --
------------------------
procedure Expand_Source_Info (N : Node_Id; Nam : Name_Id) is
Loc : constant Source_Ptr := Sloc (N);
Ent : Entity_Id;
procedure Write_Entity_Name (E : Entity_Id);
-- Recursive procedure to construct string for qualified name of
-- enclosing program unit. The qualification stops at an enclosing
-- scope has no source name (block or loop). If entity is a subprogram
-- instance, skip enclosing wrapper package.
-----------------------
-- Write_Entity_Name --
-----------------------
procedure Write_Entity_Name (E : Entity_Id) is
SDef : Source_Ptr;
TDef : constant Source_Buffer_Ptr :=
Source_Text (Get_Source_File_Index (Sloc (E)));
begin
-- Nothing to do if at outer level
if Scope (E) = Standard_Standard then
null;
-- If scope comes from source, write its name
elsif Comes_From_Source (Scope (E)) then
Write_Entity_Name (Scope (E));
Add_Char_To_Name_Buffer ('.');
-- If in wrapper package skip past it
elsif Is_Wrapper_Package (Scope (E)) then
Write_Entity_Name (Scope (Scope (E)));
Add_Char_To_Name_Buffer ('.');
-- Otherwise nothing to output (happens in unnamed block statements)
else
null;
end if;
-- Loop to output the name
-- is this right wrt wide char encodings ??? (no!)
SDef := Sloc (E);
while TDef (SDef) in '0' .. '9'
or else TDef (SDef) >= 'A'
or else TDef (SDef) = ASCII.ESC
loop
Add_Char_To_Name_Buffer (TDef (SDef));
SDef := SDef + 1;
end loop;
end Write_Entity_Name;
-- Start of processing for Expand_Source_Info
begin
-- Integer cases
if Nam = Name_Line then
Rewrite (N,
Make_Integer_Literal (Loc,
Intval => UI_From_Int (Int (Get_Logical_Line_Number (Loc)))));
Analyze_And_Resolve (N, Standard_Positive);
-- String cases
else
Name_Len := 0;
case Nam is
when Name_File =>
Get_Decoded_Name_String
(Reference_Name (Get_Source_File_Index (Loc)));
when Name_Source_Location =>
Build_Location_String (Loc);
when Name_Enclosing_Entity =>
-- Skip enclosing blocks to reach enclosing unit
Ent := Current_Scope;
while Present (Ent) loop
exit when Ekind (Ent) /= E_Block
and then Ekind (Ent) /= E_Loop;
Ent := Scope (Ent);
end loop;
-- Ent now points to the relevant defining entity
Write_Entity_Name (Ent);
when others =>
raise Program_Error;
end case;
Rewrite (N,
Make_String_Literal (Loc,
Strval => String_From_Name_Buffer));
Analyze_And_Resolve (N, Standard_String);
end if;
Set_Is_Static_Expression (N);
end Expand_Source_Info;
---------------------------
-- Expand_Unc_Conversion --
---------------------------
procedure Expand_Unc_Conversion (N : Node_Id; E : Entity_Id) is
Func : constant Entity_Id := Entity (Name (N));
Conv : Node_Id;
Ftyp : Entity_Id;
Ttyp : Entity_Id;
begin
-- Rewrite as unchecked conversion node. Note that we must convert
-- the operand to the formal type of the input parameter of the
-- function, so that the resulting N_Unchecked_Type_Conversion
-- call indicates the correct types for Gigi.
-- Right now, we only do this if a scalar type is involved. It is
-- not clear if it is needed in other cases. If we do attempt to
-- do the conversion unconditionally, it crashes 3411-018. To be
-- investigated further ???
Conv := Relocate_Node (First_Actual (N));
Ftyp := Etype (First_Formal (Func));
if Is_Scalar_Type (Ftyp) then
Conv := Convert_To (Ftyp, Conv);
Set_Parent (Conv, N);
Analyze_And_Resolve (Conv);
end if;
-- The instantiation of Unchecked_Conversion creates a wrapper package,
-- and the target type is declared as a subtype of the actual. Recover
-- the actual, which is the subtype indic. in the subtype declaration
-- for the target type. This is semantically correct, and avoids
-- anomalies with access subtypes. For entities, leave type as is.
-- We do the analysis here, because we do not want the compiler
-- to try to optimize or otherwise reorganize the unchecked
-- conversion node.
Ttyp := Etype (E);
if Is_Entity_Name (Conv) then
null;
elsif Nkind (Parent (Ttyp)) = N_Subtype_Declaration then
Ttyp := Entity (Subtype_Indication (Parent (Etype (E))));
elsif Is_Itype (Ttyp) then
Ttyp :=
Entity (Subtype_Indication (Associated_Node_For_Itype (Ttyp)));
else
raise Program_Error;
end if;
Rewrite (N, Unchecked_Convert_To (Ttyp, Conv));
Set_Etype (N, Ttyp);
Set_Analyzed (N);
if Nkind (N) = N_Unchecked_Type_Conversion then
Expand_N_Unchecked_Type_Conversion (N);
end if;
end Expand_Unc_Conversion;
-----------------------------
-- Expand_Unc_Deallocation --
-----------------------------
-- Generate the following Code :
-- if Arg /= null then
-- <Finalize_Call> (.., T'Class(Arg.all), ..); -- for controlled types
-- Free (Arg);
-- Arg := Null;
-- end if;
-- For a task, we also generate a call to Free_Task to ensure that the
-- task itself is freed if it is terminated, ditto for a simple protected
-- object, with a call to Finalize_Protection. For composite types that
-- have tasks or simple protected objects as components, we traverse the
-- structures to find and terminate those components.
procedure Expand_Unc_Deallocation (N : Node_Id) is
Arg : constant Node_Id := First_Actual (N);
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (Arg);
Desig_T : constant Entity_Id := Designated_Type (Typ);
Rtyp : constant Entity_Id := Underlying_Type (Root_Type (Typ));
Pool : constant Entity_Id := Associated_Storage_Pool (Rtyp);
Stmts : constant List_Id := New_List;
Needs_Fin : constant Boolean := Needs_Finalization (Desig_T);
Finalizer_Data : Finalization_Exception_Data;
Blk : Node_Id := Empty;
Deref : Node_Id;
Final_Code : List_Id;
Free_Arg : Node_Id;
Free_Node : Node_Id;
Gen_Code : Node_Id;
Arg_Known_Non_Null : constant Boolean := Known_Non_Null (N);
-- This captures whether we know the argument to be non-null so that
-- we can avoid the test. The reason that we need to capture this is
-- that we analyze some generated statements before properly attaching
-- them to the tree, and that can disturb current value settings.
begin
-- Nothing to do if we know the argument is null
if Known_Null (N) then
return;
end if;
-- Processing for pointer to controlled type
if Needs_Fin then
Deref :=
Make_Explicit_Dereference (Loc,
Prefix => Duplicate_Subexpr_No_Checks (Arg));
-- If the type is tagged, then we must force dispatching on the
-- finalization call because the designated type may not be the
-- actual type of the object.
if Is_Tagged_Type (Desig_T)
and then not Is_Class_Wide_Type (Desig_T)
then
Deref := Unchecked_Convert_To (Class_Wide_Type (Desig_T), Deref);
elsif not Is_Tagged_Type (Desig_T) then
-- Set type of result, to force a conversion when needed (see
-- exp_ch7, Convert_View), given that Deep_Finalize may be
-- inherited from the parent type, and we need the type of the
-- expression to see whether the conversion is in fact needed.
Set_Etype (Deref, Desig_T);
end if;
-- The finalization call is expanded wrapped in a block to catch any
-- possible exception. If an exception does occur, then Program_Error
-- must be raised following the freeing of the object and its removal
-- from the finalization collection's list. We set a flag to record
-- that an exception was raised, and save its occurrence for use in
-- the later raise.
--
-- Generate:
-- Abort : constant Boolean :=
-- Exception_Occurrence (Get_Current_Excep.all.all) =
-- Standard'Abort_Signal'Identity;
-- <or>
-- Abort : constant Boolean := False; -- no abort
-- E : Exception_Occurrence;
-- Raised : Boolean := False;
--
-- begin
-- [Deep_]Finalize (Obj);
-- exception
-- when others =>
-- Raised := True;
-- Save_Occurrence (E, Get_Current_Excep.all.all);
-- end;
Build_Object_Declarations (Finalizer_Data, Stmts, Loc);
Final_Code := New_List (
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Final_Call (Obj_Ref => Deref, Typ => Desig_T)),
Exception_Handlers => New_List (
Build_Exception_Handler (Finalizer_Data)))));
-- For .NET/JVM, detach the object from the containing finalization
-- collection before finalizing it.
if VM_Target /= No_VM and then Is_Controlled (Desig_T) then
Prepend_To (Final_Code,
Make_Detach_Call (New_Copy_Tree (Arg)));
end if;
-- If aborts are allowed, then the finalization code must be
-- protected by an abort defer/undefer pair.
if Abort_Allowed then
Prepend_To (Final_Code,
Build_Runtime_Call (Loc, RE_Abort_Defer));
Blk :=
Make_Block_Statement (Loc, Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Final_Code,
At_End_Proc =>
New_Occurrence_Of (RTE (RE_Abort_Undefer_Direct), Loc)));
Append (Blk, Stmts);
else
Append_List_To (Stmts, Final_Code);
end if;
end if;
-- For a task type, call Free_Task before freeing the ATCB
if Is_Task_Type (Desig_T) then
declare
Stat : Node_Id := Prev (N);
Nam1 : Node_Id;
Nam2 : Node_Id;
begin
-- An Abort followed by a Free will not do what the user expects,
-- because the abort is not immediate. This is worth a warning.
while Present (Stat)
and then not Comes_From_Source (Original_Node (Stat))
loop
Prev (Stat);
end loop;
if Present (Stat)
and then Nkind (Original_Node (Stat)) = N_Abort_Statement
then
Stat := Original_Node (Stat);
Nam1 := First (Names (Stat));
Nam2 := Original_Node (First (Parameter_Associations (N)));
if Nkind (Nam1) = N_Explicit_Dereference
and then Is_Entity_Name (Prefix (Nam1))
and then Is_Entity_Name (Nam2)
and then Entity (Prefix (Nam1)) = Entity (Nam2)
then
Error_Msg_N ("abort may take time to complete??", N);
Error_Msg_N ("\deallocation might have no effect??", N);
Error_Msg_N ("\safer to wait for termination??", N);
end if;
end if;
end;
Append_To
(Stmts, Cleanup_Task (N, Duplicate_Subexpr_No_Checks (Arg)));
-- For composite types that contain tasks, recurse over the structure
-- to build the selectors for the task subcomponents.
elsif Has_Task (Desig_T) then
if Is_Record_Type (Desig_T) then
Append_List_To (Stmts, Cleanup_Record (N, Arg, Desig_T));
elsif Is_Array_Type (Desig_T) then
Append_List_To (Stmts, Cleanup_Array (N, Arg, Desig_T));
end if;
end if;
-- Same for simple protected types. Eventually call Finalize_Protection
-- before freeing the PO for each protected component.
if Is_Simple_Protected_Type (Desig_T) then
Append_To (Stmts,
Cleanup_Protected_Object (N, Duplicate_Subexpr_No_Checks (Arg)));
elsif Has_Simple_Protected_Object (Desig_T) then
if Is_Record_Type (Desig_T) then
Append_List_To (Stmts, Cleanup_Record (N, Arg, Desig_T));
elsif Is_Array_Type (Desig_T) then
Append_List_To (Stmts, Cleanup_Array (N, Arg, Desig_T));
end if;
end if;
-- Normal processing for non-controlled types
Free_Arg := Duplicate_Subexpr_No_Checks (Arg);
Free_Node := Make_Free_Statement (Loc, Empty);
Append_To (Stmts, Free_Node);
Set_Storage_Pool (Free_Node, Pool);
-- Attach to tree before analysis of generated subtypes below
Set_Parent (Stmts, Parent (N));
-- Deal with storage pool
if Present (Pool) then
-- Freeing the secondary stack is meaningless
if Is_RTE (Pool, RE_SS_Pool) then
null;
-- If the pool object is of a simple storage pool type, then attempt
-- to locate the type's Deallocate procedure, if any, and set the
-- free operation's procedure to call. If the type doesn't have a
-- Deallocate (which is allowed), then the actual will simply be set
-- to null.
elsif Present (Get_Rep_Pragma
(Etype (Pool), Name_Simple_Storage_Pool_Type))
then
declare
Pool_Type : constant Entity_Id := Base_Type (Etype (Pool));
Dealloc_Op : Entity_Id;
begin
Dealloc_Op := Get_Name_Entity_Id (Name_Deallocate);
while Present (Dealloc_Op) loop
if Scope (Dealloc_Op) = Scope (Pool_Type)
and then Present (First_Formal (Dealloc_Op))
and then Etype (First_Formal (Dealloc_Op)) = Pool_Type
then
Set_Procedure_To_Call (Free_Node, Dealloc_Op);
exit;
else
Dealloc_Op := Homonym (Dealloc_Op);
end if;
end loop;
end;
-- Case of a class-wide pool type: make a dispatching call to
-- Deallocate through the class-wide Deallocate_Any.
elsif Is_Class_Wide_Type (Etype (Pool)) then
Set_Procedure_To_Call (Free_Node, RTE (RE_Deallocate_Any));
-- Case of a specific pool type: make a statically bound call
else
Set_Procedure_To_Call (Free_Node,
Find_Prim_Op (Etype (Pool), Name_Deallocate));
end if;
end if;
if Present (Procedure_To_Call (Free_Node)) then
-- For all cases of a Deallocate call, the back-end needs to be able
-- to compute the size of the object being freed. This may require
-- some adjustments for objects of dynamic size.
--
-- If the type is class wide, we generate an implicit type with the
-- right dynamic size, so that the deallocate call gets the right
-- size parameter computed by GIGI. Same for an access to
-- unconstrained packed array.
if Is_Class_Wide_Type (Desig_T)
or else
(Is_Array_Type (Desig_T)
and then not Is_Constrained (Desig_T)
and then Is_Packed (Desig_T))
then
declare
Deref : constant Node_Id :=
Make_Explicit_Dereference (Loc,
Duplicate_Subexpr_No_Checks (Arg));
D_Subtyp : Node_Id;
D_Type : Entity_Id;
begin
-- Perform minor decoration as it is needed by the side effect
-- removal mechanism.
Set_Etype (Deref, Desig_T);
Set_Parent (Deref, Free_Node);
D_Subtyp := Make_Subtype_From_Expr (Deref, Desig_T);
if Nkind (D_Subtyp) in N_Has_Entity then
D_Type := Entity (D_Subtyp);
else
D_Type := Make_Temporary (Loc, 'A');
Insert_Action (Deref,
Make_Subtype_Declaration (Loc,
Defining_Identifier => D_Type,
Subtype_Indication => D_Subtyp));
end if;
-- Force freezing at the point of the dereference. For the
-- class wide case, this avoids having the subtype frozen
-- before the equivalent type.
Freeze_Itype (D_Type, Deref);
Set_Actual_Designated_Subtype (Free_Node, D_Type);
end;
end if;
end if;
-- Ada 2005 (AI-251): In case of abstract interface type we must
-- displace the pointer to reference the base of the object to
-- deallocate its memory, unless we're targetting a VM, in which case
-- no special processing is required.
-- Generate:
-- free (Base_Address (Obj_Ptr))
if Is_Interface (Directly_Designated_Type (Typ))
and then Tagged_Type_Expansion
then
Set_Expression (Free_Node,
Unchecked_Convert_To (Typ,
Make_Function_Call (Loc,
Name => New_Reference_To (RTE (RE_Base_Address), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Free_Arg)))));
-- Generate:
-- free (Obj_Ptr)
else
Set_Expression (Free_Node, Free_Arg);
end if;
-- Only remaining step is to set result to null, or generate a raise of
-- Constraint_Error if the target object is "not null".
if Can_Never_Be_Null (Etype (Arg)) then
Append_To (Stmts,
Make_Raise_Constraint_Error (Loc,
Reason => CE_Access_Check_Failed));
else
declare
Lhs : constant Node_Id := Duplicate_Subexpr_No_Checks (Arg);
begin
Set_Assignment_OK (Lhs);
Append_To (Stmts,
Make_Assignment_Statement (Loc,
Name => Lhs,
Expression => Make_Null (Loc)));
end;
end if;
-- Generate a test of whether any earlier finalization raised an
-- exception, and in that case raise Program_Error with the previous
-- exception occurrence.
-- Generate:
-- if Raised and then not Abort then
-- raise Program_Error; -- for .NET and
-- -- restricted RTS
-- <or>
-- Raise_From_Controlled_Operation (E); -- all other cases
-- end if;
if Needs_Fin then
Append_To (Stmts, Build_Raise_Statement (Finalizer_Data));
end if;
-- If we know the argument is non-null, then make a block statement
-- that contains the required statements, no need for a test.
if Arg_Known_Non_Null then
Gen_Code :=
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts));
-- If the argument may be null, wrap the statements inside an IF that
-- does an explicit test to exclude the null case.
else
Gen_Code :=
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Ne (Loc,
Left_Opnd => Duplicate_Subexpr (Arg),
Right_Opnd => Make_Null (Loc)),
Then_Statements => Stmts);
end if;
-- Rewrite the call
Rewrite (N, Gen_Code);
Analyze (N);
-- If we generated a block with an At_End_Proc, expand the exception
-- handler. We need to wait until after everything else is analyzed.
if Present (Blk) then
Expand_At_End_Handler
(Handled_Statement_Sequence (Blk), Entity (Identifier (Blk)));
end if;
end Expand_Unc_Deallocation;
-----------------------
-- Expand_To_Address --
-----------------------
procedure Expand_To_Address (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Arg : constant Node_Id := First_Actual (N);
Obj : Node_Id;
begin
Remove_Side_Effects (Arg);
Obj := Make_Explicit_Dereference (Loc, Relocate_Node (Arg));
Rewrite (N,
Make_If_Expression (Loc,
Expressions => New_List (
Make_Op_Eq (Loc,
Left_Opnd => New_Copy_Tree (Arg),
Right_Opnd => Make_Null (Loc)),
New_Occurrence_Of (RTE (RE_Null_Address), Loc),
Make_Attribute_Reference (Loc,
Prefix => Obj,
Attribute_Name => Name_Address))));
Analyze_And_Resolve (N, RTE (RE_Address));
end Expand_To_Address;
-----------------------
-- Expand_To_Pointer --
-----------------------
procedure Expand_To_Pointer (N : Node_Id) is
Arg : constant Node_Id := First_Actual (N);
begin
Rewrite (N, Unchecked_Convert_To (Etype (N), Arg));
Analyze (N);
end Expand_To_Pointer;
end Exp_Intr;