------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                             E X P _ C O D E                              --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--             Copyright (C) 1996 Free Software Foundation, Inc.            --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 2,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
-- for  more details.  You should have  received  a copy of the GNU General --
-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
-- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
-- MA 02111-1307, USA.                                                      --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

--  Processing for handling code statements

with Types; use Types;

with System; use System;
package Exp_Code is

   procedure Expand_Asm_Call (N : Node_Id);
   --  Expands a call to Asm or Asm_Volatile into an equivalent
   --  N_Code_Statement node.

   --  The following routines provide an abstract interface to analyze
   --  code statements, for use by Gigi processing for code statements.
   --  Note that the implementations of these routines must not attempt
   --  to expand tables that are frozen on entry to Gigi.

   function Is_Asm_Volatile (N : Node_Id) return Boolean;
   --  Given an N_Code_Statement node N, return True in the Asm_Volatile
   --  case and False in the Asm case.

   function Asm_Template (N : Node_Id) return Node_Id;
   --  Given an N_Code_Statement node N, returns string literal node for
   --  template in call

   procedure Clobber_Setup (N : Node_Id);
   --  Given an N_Code_Statement node N, setup to process the clobber list
   --  with subsequent calls to Clobber_Get_Next.

   function Clobber_Get_Next return System.Address;
   --  Can only be called after a previous call to Clobber_Setup. The
   --  returned value is a pointer to a null terminated (C format) string
   --  for the next register argument. Null_Address is returned when there
   --  are no more arguments.

   procedure Setup_Asm_Inputs (N : Node_Id);
   --  Given an N_Code_Statement node N, setup to read list of Asm_Input
   --  arguments. The protocol is to construct a loop as follows:
   --
   --    Setup_Asm_Inputs (N);
   --    while Present (Asm_Input_Value)
   --      body
   --      Next_Asm_Input;
   --    end loop;
   --
   --  where the loop body calls Asm_Input_Constraint or Asm_Input_Value to
   --  obtain the constraint string or input value expression from the current
   --  Asm_Input argument.

   function Asm_Input_Constraint return Node_Id;
   --  Called within a loop initialized by Setup_Asm_Inputs and controlled
   --  by Next_Asm_Input as described above. Returns a string literal node
   --  for the constraint component of the current Asm_Input_Parameter, or
   --  Empty if there are no more Asm_Input parameters.

   function Asm_Input_Value return Node_Id;
   --  Called within a loop initialized by Setup_Asm_Inputs and controlled
   --  by Next_Asm_Input as described above. Returns the expression node for
   --  the value component of the current Asm_Input parameter, or Empty if
   --  there are no more Asm_Input parameters.

   procedure Next_Asm_Input;
   --  Step to next Asm_Input parameter. It is an error to call this procedure
   --  if there are no more available parameters (which is impossible if the
   --  call appears in a loop as in the above example).

   procedure Setup_Asm_Outputs (N : Node_Id);
   --  Given an N_Code_Statement node N, setup to read list of Asm_Output
   --  arguments. The protocol is to construct a loop as follows:
   --
   --    Setup_Asm_Outputs (N);
   --    while Present (Asm_Output_Value)
   --      body
   --      Next_Asm_Output;
   --    end loop;
   --
   --  where the loop body calls Asm_Output_Constraint or Asm_Output_Variable
   --  to obtain the constraint string or output variable name from the current
   --  Asm_Output argument.

   function Asm_Output_Constraint return Node_Id;
   --  Called within a loop initialized by Setup_Asm_Outputs and controlled
   --  by Next_Asm_Output as described above. Returns a string literal node
   --  for the constraint component of the current Asm_Output_Parameter, or
   --  Empty if there are no more Asm_Output parameters.

   function Asm_Output_Variable return Node_Id;
   --  Called within a loop initialized by Setup_Asm_Outputs and controlled
   --  by Next_Asm_Output as described above. Returns the expression node for
   --  the output variable component of the current Asm_Output parameter, or
   --  Empty if there are no more Asm_Output parameters.

   procedure Next_Asm_Output;
   --  Step to next Asm_Output parameter. It is an error to call this procedure
   --  if there are no more available parameters (which is impossible if the
   --  call appears in a loop as in the above example).

end Exp_Code;
