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|
------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M _ E L I M --
-- --
-- B o d y --
-- --
-- Copyright (C) 1997-2020, 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 Einfo; use Einfo;
with Errout; use Errout;
with Lib; use Lib;
with Namet; use Namet;
with Nlists; use Nlists;
with Opt; use Opt;
with Sem; use Sem;
with Sem_Aux; use Sem_Aux;
with Sem_Prag; use Sem_Prag;
with Sem_Util; use Sem_Util;
with Sinput; use Sinput;
with Sinfo; use Sinfo;
with Snames; use Snames;
with Stand; use Stand;
with Stringt; use Stringt;
with Table;
with GNAT.HTable; use GNAT.HTable;
package body Sem_Elim is
No_Elimination : Boolean;
-- Set True if no Eliminate pragmas active
---------------------
-- Data Structures --
---------------------
-- A single pragma Eliminate is represented by the following record
type Elim_Data;
type Access_Elim_Data is access Elim_Data;
type Names is array (Nat range <>) of Name_Id;
-- Type used to represent set of names. Used for names in Unit_Name
-- and also the set of names in Argument_Types.
type Access_Names is access Names;
type Elim_Data is record
Unit_Name : Access_Names;
-- Unit name, broken down into a set of names (e.g. A.B.C is
-- represented as Name_Id values for A, B, C in sequence).
Entity_Name : Name_Id;
-- Entity name if Entity parameter if present. If no Entity parameter
-- was supplied, then Entity_Node is set to Empty, and the Entity_Name
-- field contains the last identifier name in the Unit_Name.
Entity_Scope : Access_Names;
-- Static scope of the entity within the compilation unit represented by
-- Unit_Name.
Entity_Node : Node_Id;
-- Save node of entity argument, for posting error messages. Set
-- to Empty if there is no entity argument.
Parameter_Types : Access_Names;
-- Set to set of names given for parameter types. If no parameter
-- types argument is present, this argument is set to null.
Result_Type : Name_Id;
-- Result type name if Result_Types parameter present, No_Name if not
Source_Location : Name_Id;
-- String describing the source location of subprogram defining name if
-- Source_Location parameter present, No_Name if not
Hash_Link : Access_Elim_Data;
-- Link for hash table use
Homonym : Access_Elim_Data;
-- Pointer to next entry with same key
Prag : Node_Id;
-- Node_Id for Eliminate pragma
end record;
----------------
-- Hash_Table --
----------------
-- Setup hash table using the Entity_Name field as the hash key
subtype Element is Elim_Data;
subtype Elmt_Ptr is Access_Elim_Data;
subtype Key is Name_Id;
type Header_Num is range 0 .. 1023;
Null_Ptr : constant Elmt_Ptr := null;
----------------------
-- Hash_Subprograms --
----------------------
package Hash_Subprograms is
function Equal (F1, F2 : Key) return Boolean;
pragma Inline (Equal);
function Get_Key (E : Elmt_Ptr) return Key;
pragma Inline (Get_Key);
function Hash (F : Key) return Header_Num;
pragma Inline (Hash);
function Next (E : Elmt_Ptr) return Elmt_Ptr;
pragma Inline (Next);
procedure Set_Next (E : Elmt_Ptr; Next : Elmt_Ptr);
pragma Inline (Set_Next);
end Hash_Subprograms;
package body Hash_Subprograms is
-----------
-- Equal --
-----------
function Equal (F1, F2 : Key) return Boolean is
begin
return F1 = F2;
end Equal;
-------------
-- Get_Key --
-------------
function Get_Key (E : Elmt_Ptr) return Key is
begin
return E.Entity_Name;
end Get_Key;
----------
-- Hash --
----------
function Hash (F : Key) return Header_Num is
begin
return Header_Num (Int (F) mod 1024);
end Hash;
----------
-- Next --
----------
function Next (E : Elmt_Ptr) return Elmt_Ptr is
begin
return E.Hash_Link;
end Next;
--------------
-- Set_Next --
--------------
procedure Set_Next (E : Elmt_Ptr; Next : Elmt_Ptr) is
begin
E.Hash_Link := Next;
end Set_Next;
end Hash_Subprograms;
------------
-- Tables --
------------
-- The following table records the data for each pragma, using the
-- entity name as the hash key for retrieval. Entries in this table
-- are set by Process_Eliminate_Pragma and read by Check_Eliminated.
package Elim_Hash_Table is new Static_HTable (
Header_Num => Header_Num,
Element => Element,
Elmt_Ptr => Elmt_Ptr,
Null_Ptr => Null_Ptr,
Set_Next => Hash_Subprograms.Set_Next,
Next => Hash_Subprograms.Next,
Key => Key,
Get_Key => Hash_Subprograms.Get_Key,
Hash => Hash_Subprograms.Hash,
Equal => Hash_Subprograms.Equal);
-- The following table records entities for subprograms that are
-- eliminated, and corresponding eliminate pragmas that caused the
-- elimination. Entries in this table are set by Check_Eliminated
-- and read by Eliminate_Error_Msg.
type Elim_Entity_Entry is record
Prag : Node_Id;
Subp : Entity_Id;
end record;
package Elim_Entities is new Table.Table (
Table_Component_Type => Elim_Entity_Entry,
Table_Index_Type => Name_Id'Base,
Table_Low_Bound => First_Name_Id,
Table_Initial => 50,
Table_Increment => 200,
Table_Name => "Elim_Entries");
----------------------
-- Check_Eliminated --
----------------------
procedure Check_Eliminated (E : Entity_Id) is
Elmt : Access_Elim_Data;
Scop : Entity_Id;
Form : Entity_Id;
Up : Nat;
begin
if No_Elimination then
return;
-- Elimination of objects and types is not implemented yet
elsif Ekind (E) not in Subprogram_Kind then
return;
end if;
-- Loop through homonyms for this key
Elmt := Elim_Hash_Table.Get (Chars (E));
while Elmt /= null loop
Check_Homonyms : declare
procedure Set_Eliminated;
-- Set current subprogram entity as eliminated
--------------------
-- Set_Eliminated --
--------------------
procedure Set_Eliminated is
Overridden : Entity_Id;
begin
if Is_Dispatching_Operation (E) then
-- If an overriding dispatching primitive is eliminated then
-- its parent must have been eliminated. If the parent is an
-- inherited operation, check the operation that it renames,
-- because flag Eliminated is only set on source operations.
Overridden := Overridden_Operation (E);
if Present (Overridden)
and then not Comes_From_Source (Overridden)
and then Present (Alias (Overridden))
then
Overridden := Alias (Overridden);
end if;
if Present (Overridden)
and then not Is_Eliminated (Overridden)
and then not Is_Abstract_Subprogram (Overridden)
then
Error_Msg_Name_1 := Chars (E);
Error_Msg_N ("cannot eliminate subprogram %", E);
return;
end if;
end if;
Set_Is_Eliminated (E);
Elim_Entities.Append ((Prag => Elmt.Prag, Subp => E));
end Set_Eliminated;
-- Start of processing for Check_Homonyms
begin
-- First we check that the name of the entity matches
if Elmt.Entity_Name /= Chars (E) then
goto Continue;
end if;
-- Find enclosing unit, and verify that its name and those of its
-- parents match.
Scop := Cunit_Entity (Current_Sem_Unit);
-- Now see if compilation unit matches
Up := Elmt.Unit_Name'Last;
-- If we are within a subunit, the name in the pragma has been
-- parsed as a child unit, but the current compilation unit is in
-- fact the parent in which the subunit is embedded. We must skip
-- the first name which is that of the subunit to match the pragma
-- specification. Body may be that of a package or subprogram.
declare
Par : Node_Id;
begin
Par := Parent (E);
while Present (Par) loop
if Nkind (Par) = N_Subunit then
if Chars (Defining_Entity (Proper_Body (Par))) =
Elmt.Unit_Name (Up)
then
Up := Up - 1;
exit;
else
goto Continue;
end if;
end if;
Par := Parent (Par);
end loop;
end;
for J in reverse Elmt.Unit_Name'First .. Up loop
if Elmt.Unit_Name (J) /= Chars (Scop) then
goto Continue;
end if;
Scop := Scope (Scop);
if Scop /= Standard_Standard and then J = 1 then
goto Continue;
end if;
end loop;
if Scop /= Standard_Standard then
goto Continue;
end if;
if Present (Elmt.Entity_Node)
and then Elmt.Entity_Scope /= null
then
-- Check that names of enclosing scopes match. Skip blocks and
-- wrapper package of subprogram instances, which do not appear
-- in the pragma.
Scop := Scope (E);
for J in reverse Elmt.Entity_Scope'Range loop
while Ekind (Scop) = E_Block
or else
(Ekind (Scop) = E_Package
and then Is_Wrapper_Package (Scop))
loop
Scop := Scope (Scop);
end loop;
if Elmt.Entity_Scope (J) /= Chars (Scop) then
if Ekind (Scop) /= E_Protected_Type
or else Comes_From_Source (Scop)
then
goto Continue;
-- For simple protected declarations, retrieve the source
-- name of the object, which appeared in the Eliminate
-- pragma.
else
declare
Decl : constant Node_Id :=
Original_Node (Parent (Scop));
begin
if Elmt.Entity_Scope (J) /=
Chars (Defining_Identifier (Decl))
then
if J > 0 then
null;
end if;
goto Continue;
end if;
end;
end if;
end if;
Scop := Scope (Scop);
end loop;
end if;
-- If given entity is a library level subprogram and pragma had a
-- single parameter, a match.
if Is_Compilation_Unit (E)
and then Is_Subprogram (E)
and then No (Elmt.Entity_Node)
then
Set_Eliminated;
return;
-- Check for case of type or object with two parameter case
elsif (Is_Type (E) or else Is_Object (E))
and then Elmt.Result_Type = No_Name
and then Elmt.Parameter_Types = null
then
Set_Eliminated;
return;
-- Check for case of subprogram
elsif Ekind (E) in E_Function | E_Procedure then
-- If Source_Location present, then see if it matches
if Elmt.Source_Location /= No_Name then
Get_Name_String (Elmt.Source_Location);
declare
Sloc_Trace : constant String :=
Name_Buffer (1 .. Name_Len);
Idx : Natural := Sloc_Trace'First;
-- Index in Sloc_Trace, if equals to 0, then we have
-- completely traversed Sloc_Trace
Last : constant Natural := Sloc_Trace'Last;
P : Source_Ptr;
Sindex : Source_File_Index;
function File_Name_Match return Boolean;
-- This function is supposed to be called when Idx points
-- to the beginning of the new file name, and Name_Buffer
-- is set to contain the name of the proper source file
-- from the chain corresponding to the Sloc of E. First
-- it checks that these two files have the same name. If
-- this check is successful, moves Idx to point to the
-- beginning of the column number.
function Line_Num_Match return Boolean;
-- This function is supposed to be called when Idx points
-- to the beginning of the column number, and P is
-- set to point to the proper Sloc the chain
-- corresponding to the Sloc of E. First it checks that
-- the line number Idx points on and the line number
-- corresponding to P are the same. If this check is
-- successful, moves Idx to point to the beginning of
-- the next file name in Sloc_Trace. If there is no file
-- name any more, Idx is set to 0.
function Different_Trace_Lengths return Boolean;
-- From Idx and P, defines if there are in both traces
-- more element(s) in the instantiation chains. Returns
-- False if one trace contains more element(s), but
-- another does not. If both traces contains more
-- elements (that is, the function returns False), moves
-- P ahead in the chain corresponding to E, recomputes
-- Sindex and sets the name of the corresponding file in
-- Name_Buffer
function Skip_Spaces return Natural;
-- If Sloc_Trace (Idx) is not space character, returns
-- Idx. Otherwise returns the index of the nearest
-- non-space character in Sloc_Trace to the right of Idx.
-- Returns 0 if there is no such character.
-----------------------------
-- Different_Trace_Lengths --
-----------------------------
function Different_Trace_Lengths return Boolean is
begin
P := Instantiation (Sindex);
if (P = No_Location and then Idx /= 0)
or else
(P /= No_Location and then Idx = 0)
then
return True;
else
if P /= No_Location then
Sindex := Get_Source_File_Index (P);
Get_Name_String (File_Name (Sindex));
end if;
return False;
end if;
end Different_Trace_Lengths;
---------------------
-- File_Name_Match --
---------------------
function File_Name_Match return Boolean is
Tmp_Idx : Natural;
End_Idx : Natural;
begin
if Idx = 0 then
return False;
end if;
-- Find first colon. If no colon, then return False.
-- If there is a colon, Tmp_Idx is set to point just
-- before the colon.
Tmp_Idx := Idx - 1;
loop
if Tmp_Idx >= Last then
return False;
elsif Sloc_Trace (Tmp_Idx + 1) = ':' then
exit;
else
Tmp_Idx := Tmp_Idx + 1;
end if;
end loop;
-- Find last non-space before this colon. If there is
-- no space character before this colon, then return
-- False. Otherwise, End_Idx is set to point to this
-- non-space character.
End_Idx := Tmp_Idx;
loop
if End_Idx < Idx then
return False;
elsif Sloc_Trace (End_Idx) /= ' ' then
exit;
else
End_Idx := End_Idx - 1;
end if;
end loop;
-- Now see if file name matches what is in Name_Buffer
-- and if so, step Idx past it and return True. If the
-- name does not match, return False.
if Sloc_Trace (Idx .. End_Idx) =
Name_Buffer (1 .. Name_Len)
then
Idx := Tmp_Idx + 2;
Idx := Skip_Spaces;
return True;
else
return False;
end if;
end File_Name_Match;
--------------------
-- Line_Num_Match --
--------------------
function Line_Num_Match return Boolean is
N : Nat := 0;
begin
if Idx = 0 then
return False;
end if;
while Idx <= Last
and then Sloc_Trace (Idx) in '0' .. '9'
loop
N := N * 10 +
(Character'Pos (Sloc_Trace (Idx)) -
Character'Pos ('0'));
Idx := Idx + 1;
end loop;
if Get_Physical_Line_Number (P) =
Physical_Line_Number (N)
then
while Idx <= Last and then
Sloc_Trace (Idx) /= '['
loop
Idx := Idx + 1;
end loop;
if Idx <= Last then
pragma Assert (Sloc_Trace (Idx) = '[');
Idx := Idx + 1;
Idx := Skip_Spaces;
else
Idx := 0;
end if;
return True;
else
return False;
end if;
end Line_Num_Match;
-----------------
-- Skip_Spaces --
-----------------
function Skip_Spaces return Natural is
Res : Natural;
begin
Res := Idx;
while Sloc_Trace (Res) = ' ' loop
Res := Res + 1;
if Res > Last then
Res := 0;
exit;
end if;
end loop;
return Res;
end Skip_Spaces;
begin
P := Sloc (E);
Sindex := Get_Source_File_Index (P);
Get_Name_String (File_Name (Sindex));
Idx := Skip_Spaces;
while Idx > 0 loop
if not File_Name_Match then
goto Continue;
elsif not Line_Num_Match then
goto Continue;
end if;
if Different_Trace_Lengths then
goto Continue;
end if;
end loop;
end;
end if;
-- If we have a Result_Type, then we must have a function with
-- the proper result type.
if Elmt.Result_Type /= No_Name then
if Ekind (E) /= E_Function
or else Chars (Etype (E)) /= Elmt.Result_Type
then
goto Continue;
end if;
end if;
-- If we have Parameter_Types, they must match
if Elmt.Parameter_Types /= null then
Form := First_Formal (E);
if No (Form)
and then Elmt.Parameter_Types'Length = 1
and then Elmt.Parameter_Types (1) = No_Name
then
-- Parameterless procedure matches
null;
elsif Elmt.Parameter_Types = null then
goto Continue;
else
for J in Elmt.Parameter_Types'Range loop
if No (Form)
or else
Chars (Etype (Form)) /= Elmt.Parameter_Types (J)
then
goto Continue;
else
Next_Formal (Form);
end if;
end loop;
if Present (Form) then
goto Continue;
end if;
end if;
end if;
-- If we fall through, this is match
Set_Eliminated;
return;
end if;
end Check_Homonyms;
<<Continue>>
Elmt := Elmt.Homonym;
end loop;
return;
end Check_Eliminated;
-------------------------------------
-- Check_For_Eliminated_Subprogram --
-------------------------------------
procedure Check_For_Eliminated_Subprogram (N : Node_Id; S : Entity_Id) is
Ultimate_Subp : constant Entity_Id := Ultimate_Alias (S);
Enclosing_Subp : Entity_Id;
begin
-- No check needed within a default expression for a formal, since this
-- is not really a use, and the expression (a call or attribute) may
-- never be used if the enclosing subprogram is itself eliminated.
if In_Spec_Expression then
return;
end if;
if Is_Eliminated (Ultimate_Subp)
and then not Inside_A_Generic
and then not Is_Generic_Unit (Cunit_Entity (Current_Sem_Unit))
then
Enclosing_Subp := Current_Subprogram;
while Present (Enclosing_Subp) loop
if Is_Eliminated (Enclosing_Subp) then
return;
end if;
Enclosing_Subp := Enclosing_Subprogram (Enclosing_Subp);
end loop;
-- Emit error, unless we are within an instance body and the expander
-- is disabled, indicating an instance within an enclosing generic.
-- In an instance, the ultimate alias is an internal entity, so place
-- the message on the original subprogram.
if In_Instance_Body and then not Expander_Active then
null;
elsif Comes_From_Source (Ultimate_Subp) then
Eliminate_Error_Msg (N, Ultimate_Subp);
else
Eliminate_Error_Msg (N, S);
end if;
end if;
end Check_For_Eliminated_Subprogram;
-------------------------
-- Eliminate_Error_Msg --
-------------------------
procedure Eliminate_Error_Msg (N : Node_Id; E : Entity_Id) is
begin
for J in Elim_Entities.First .. Elim_Entities.Last loop
if E = Elim_Entities.Table (J).Subp then
Error_Msg_Sloc := Sloc (Elim_Entities.Table (J).Prag);
Error_Msg_NE ("cannot reference subprogram & eliminated #", N, E);
return;
end if;
end loop;
-- If this is an internal operation generated for a protected operation,
-- its name does not match the source name, so just report the error.
if not Comes_From_Source (E)
and then Present (First_Entity (E))
and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
then
Error_Msg_NE
("cannot reference eliminated protected subprogram&", N, E);
-- Otherwise should not fall through, entry should be in table
else
Error_Msg_NE
("subprogram& is called but its alias is eliminated", N, E);
-- raise Program_Error;
end if;
end Eliminate_Error_Msg;
----------------
-- Initialize --
----------------
procedure Initialize is
begin
Elim_Hash_Table.Reset;
Elim_Entities.Init;
No_Elimination := True;
end Initialize;
------------------------------
-- Process_Eliminate_Pragma --
------------------------------
procedure Process_Eliminate_Pragma
(Pragma_Node : Node_Id;
Arg_Unit_Name : Node_Id;
Arg_Entity : Node_Id;
Arg_Parameter_Types : Node_Id;
Arg_Result_Type : Node_Id;
Arg_Source_Location : Node_Id)
is
Data : constant Access_Elim_Data := new Elim_Data;
-- Build result data here
Elmt : Access_Elim_Data;
Num_Names : Nat := 0;
-- Number of names in unit name
Lit : Node_Id;
Arg_Ent : Entity_Id;
Arg_Uname : Node_Id;
function OK_Selected_Component (N : Node_Id) return Boolean;
-- Test if N is a selected component with all identifiers, or a selected
-- component whose selector is an operator symbol. As a side effect
-- if result is True, sets Num_Names to the number of names present
-- (identifiers, and operator if any).
---------------------------
-- OK_Selected_Component --
---------------------------
function OK_Selected_Component (N : Node_Id) return Boolean is
begin
if Nkind (N) = N_Identifier
or else Nkind (N) = N_Operator_Symbol
then
Num_Names := Num_Names + 1;
return True;
elsif Nkind (N) = N_Selected_Component then
return OK_Selected_Component (Prefix (N))
and then OK_Selected_Component (Selector_Name (N));
else
return False;
end if;
end OK_Selected_Component;
-- Start of processing for Process_Eliminate_Pragma
begin
Data.Prag := Pragma_Node;
Error_Msg_Name_1 := Name_Eliminate;
-- Process Unit_Name argument
if Nkind (Arg_Unit_Name) = N_Identifier then
Data.Unit_Name := new Names'(1 => Chars (Arg_Unit_Name));
Num_Names := 1;
elsif OK_Selected_Component (Arg_Unit_Name) then
Data.Unit_Name := new Names (1 .. Num_Names);
Arg_Uname := Arg_Unit_Name;
for J in reverse 2 .. Num_Names loop
Data.Unit_Name (J) := Chars (Selector_Name (Arg_Uname));
Arg_Uname := Prefix (Arg_Uname);
end loop;
Data.Unit_Name (1) := Chars (Arg_Uname);
else
Error_Msg_N
("wrong form for Unit_Name parameter of pragma%", Arg_Unit_Name);
return;
end if;
-- Process Entity argument
if Present (Arg_Entity) then
Num_Names := 0;
if Nkind (Arg_Entity) = N_Identifier
or else Nkind (Arg_Entity) = N_Operator_Symbol
then
Data.Entity_Name := Chars (Arg_Entity);
Data.Entity_Node := Arg_Entity;
Data.Entity_Scope := null;
elsif OK_Selected_Component (Arg_Entity) then
Data.Entity_Scope := new Names (1 .. Num_Names - 1);
Data.Entity_Name := Chars (Selector_Name (Arg_Entity));
Data.Entity_Node := Arg_Entity;
Arg_Ent := Prefix (Arg_Entity);
for J in reverse 2 .. Num_Names - 1 loop
Data.Entity_Scope (J) := Chars (Selector_Name (Arg_Ent));
Arg_Ent := Prefix (Arg_Ent);
end loop;
Data.Entity_Scope (1) := Chars (Arg_Ent);
elsif Is_Config_Static_String (Arg_Entity) then
Data.Entity_Name := Name_Find;
Data.Entity_Node := Arg_Entity;
else
return;
end if;
else
Data.Entity_Node := Empty;
Data.Entity_Name := Data.Unit_Name (Num_Names);
end if;
-- Process Parameter_Types argument
if Present (Arg_Parameter_Types) then
-- Here for aggregate case
if Nkind (Arg_Parameter_Types) = N_Aggregate then
Data.Parameter_Types :=
new Names
(1 .. List_Length (Expressions (Arg_Parameter_Types)));
Lit := First (Expressions (Arg_Parameter_Types));
for J in Data.Parameter_Types'Range loop
if Is_Config_Static_String (Lit) then
Data.Parameter_Types (J) := Name_Find;
Next (Lit);
else
return;
end if;
end loop;
-- Otherwise we must have case of one name, which looks like a
-- parenthesized literal rather than an aggregate.
elsif Paren_Count (Arg_Parameter_Types) /= 1 then
Error_Msg_N
("wrong form for argument of pragma Eliminate",
Arg_Parameter_Types);
return;
elsif Is_Config_Static_String (Arg_Parameter_Types) then
String_To_Name_Buffer (Strval (Arg_Parameter_Types));
if Name_Len = 0 then
-- Parameterless procedure
Data.Parameter_Types := new Names'(1 => No_Name);
else
Data.Parameter_Types := new Names'(1 => Name_Find);
end if;
else
return;
end if;
end if;
-- Process Result_Types argument
if Present (Arg_Result_Type) then
if Is_Config_Static_String (Arg_Result_Type) then
Data.Result_Type := Name_Find;
else
return;
end if;
-- Here if no Result_Types argument
else
Data.Result_Type := No_Name;
end if;
-- Process Source_Location argument
if Present (Arg_Source_Location) then
if Is_Config_Static_String (Arg_Source_Location) then
Data.Source_Location := Name_Find;
else
return;
end if;
else
Data.Source_Location := No_Name;
end if;
Elmt := Elim_Hash_Table.Get (Hash_Subprograms.Get_Key (Data));
-- If we already have an entry with this same key, then link
-- it into the chain of entries for this key.
if Elmt /= null then
Data.Homonym := Elmt.Homonym;
Elmt.Homonym := Data;
-- Otherwise create a new entry
else
Elim_Hash_Table.Set (Data);
end if;
No_Elimination := False;
end Process_Eliminate_Pragma;
end Sem_Elim;
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