gcc/ada/exp_code.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             E X P _ C O D E                              --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1996-2023, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
  19 -- http://www.gnu.org/licenses for a complete copy of the license.          --
  20 --                                                                          --
  21 -- GNAT was originally developed  by the GNAT team at  New York University. --
  22 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  23 --                                                                          --
  24 ------------------------------------------------------------------------------
  25
  26 --  Processing for handling code statements
  27
  28 with Types; use Types;
  29
  30 with System; use System;
  31 package Exp_Code is
  32
  33    procedure Expand_Asm_Call (N : Node_Id);
  34    --  Expands a call to Asm into an equivalent N_Code_Statement node
  35
  36    --  The following routines provide an abstract interface to analyze
  37    --  code statements, for use by Gigi processing for code statements.
  38    --  Note that the implementations of these routines must not attempt
  39    --  to expand tables that are frozen on entry to Gigi.
  40
  41    --  WARNING: There is a matching C declaration of these subprograms in fe.h
  42
  43    function Is_Asm_Volatile (N : Node_Id) return Boolean;
  44    --  Given an N_Code_Statement node N, return True if Volatile=True is
  45    --  specified, and False if Volatile=False is specified (or set by default).
  46
  47    function Asm_Template (N : Node_Id) return Node_Id;
  48    --  Given an N_Code_Statement node N, returns string literal node for
  49    --  template in call
  50
  51    procedure Clobber_Setup (N : Node_Id);
  52    --  Given an N_Code_Statement node N, setup to process the clobber list
  53    --  with subsequent calls to Clobber_Get_Next.
  54
  55    function Clobber_Get_Next return System.Address;
  56    pragma Convention (C, Clobber_Get_Next);
  57    --  Can only be called after a previous call to Clobber_Setup. The
  58    --  returned value is a pointer to a null terminated (C format) string
  59    --  for the next register argument. Null_Address is returned when there
  60    --  are no more arguments.
  61
  62    procedure Setup_Asm_Inputs (N : Node_Id);
  63    --  Given an N_Code_Statement node N, setup to read list of Asm_Input
  64    --  arguments. The protocol is to construct a loop as follows:
  65    --
  66    --    Setup_Asm_Inputs (N);
  67    --    while Present (Asm_Input_Value)
  68    --      body
  69    --      Next_Asm_Input;
  70    --    end loop;
  71    --
  72    --  where the loop body calls Asm_Input_Constraint or Asm_Input_Value to
  73    --  obtain the constraint string or input value expression from the current
  74    --  Asm_Input argument.
  75
  76    function Asm_Input_Constraint return Node_Id;
  77    --  Called within a loop initialized by Setup_Asm_Inputs and controlled
  78    --  by Next_Asm_Input as described above. Returns a string literal node
  79    --  for the constraint component of the current Asm_Input_Parameter, or
  80    --  Empty if there are no more Asm_Input parameters.
  81
  82    function Asm_Input_Value return Node_Id;
  83    --  Called within a loop initialized by Setup_Asm_Inputs and controlled
  84    --  by Next_Asm_Input as described above. Returns the expression node for
  85    --  the value component of the current Asm_Input parameter, or Empty if
  86    --  there are no more Asm_Input parameters, or Error if an error was
  87    --  previously detected in the input parameters (note that the backend
  88    --  need not worry about this case, since it won't be called if there
  89    --  were any such serious errors detected).
  90
  91    procedure Next_Asm_Input;
  92    --  Step to next Asm_Input parameter. It is an error to call this procedure
  93    --  if there are no more available parameters (which is impossible if the
  94    --  call appears in a loop as in the above example).
  95
  96    procedure Setup_Asm_Outputs (N : Node_Id);
  97    --  Given an N_Code_Statement node N, setup to read list of Asm_Output
  98    --  arguments. The protocol is to construct a loop as follows:
  99    --
 100    --    Setup_Asm_Outputs (N);
 101    --    while Present (Asm_Output_Variable)
 102    --      body
 103    --      Next_Asm_Output;
 104    --    end loop;
 105    --
 106    --  where the loop body calls Asm_Output_Constraint or Asm_Output_Variable
 107    --  to obtain the constraint string or output variable name from the current
 108    --  Asm_Output argument.
 109
 110    function Asm_Output_Constraint return Node_Id;
 111    --  Called within a loop initialized by Setup_Asm_Outputs and controlled
 112    --  by Next_Asm_Output as described above. Returns a string literal node
 113    --  for the constraint component of the current Asm_Output_Parameter, or
 114    --  Empty if there are no more Asm_Output parameters.
 115
 116    function Asm_Output_Variable return Node_Id;
 117    --  Called within a loop initialized by Setup_Asm_Outputs and controlled by
 118    --  Next_Asm_Output as described above. Returns the expression node for the
 119    --  output variable component of the current Asm_Output parameter, or Empty
 120    --  if there are no more Asm_Output parameters, or Error if an error was
 121    --  previously detected in the input parameters (note that the backend need
 122    --  not worry about this case, since it won't be called if there were any
 123    --  such serious errors detected).
 124
 125    procedure Next_Asm_Output;
 126    --  Step to next Asm_Output parameter. It is an error to call this procedure
 127    --  if there are no more available parameters (which is impossible if the
 128    --  call appears in a loop as in the above example).
 129
 130 end Exp_Code;