1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                             B A C K _ E N D                              --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2019, 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--  Call the back end with all the information needed
27
28--  Note: there are multiple bodies/variants of this package, so do not
29--  modify this spec without coordination.
30
31package Back_End is
32
33   type Back_End_Mode_Type is (
34      Generate_Object,
35      --  Full back end operation with object file generation
36
37      Declarations_Only,
38      --  Partial back end operation with no object file generation. In this
39      --  mode the only useful action performed by gigi is to process all
40      --  declarations issuing any error messages (in particular those to
41      --  do with rep clauses), and to back annotate representation info.
42
43      Skip);
44      --  Back end call is skipped (syntax only, or errors found)
45
46   pragma Convention (C, Back_End_Mode_Type);
47   for Back_End_Mode_Type use (0, 1, 2);
48
49   procedure Call_Back_End (Mode : Back_End_Mode_Type);
50   --  Call back end, i.e. make call to driver traversing the tree and
51   --  outputting code. This call is made with all tables locked. The back
52   --  end is responsible for unlocking any tables it may need to change,
53   --  and locking them again before returning.
54
55   procedure Scan_Compiler_Arguments;
56   --  Acquires command-line parameters passed to the compiler and processes
57   --  them. Calls Scan_Front_End_Switches for any front-end switches found.
58   --
59   --  The processing of arguments is private to the back end, since the way
60   --  of acquiring the arguments as well as the set of allowable back end
61   --  switches is different depending on the particular back end being used.
62   --
63   --  Any processed switches that influence the result of a compilation must
64   --  be added to the Compilation_Arguments table.
65   --
66   --  This routine is expected to set the following to True if necessary (the
67   --  default for all of these in Opt is False).
68   --
69   --    Opt.Disable_FE_Inline
70   --    Opt.Disable_FE_Inline_Always
71   --    Opt.Suppress_Control_Float_Optimizations
72   --    Opt.Generate_SCO
73   --    Opt.Generate_SCO_Instance_Table
74   --    Opt.Stack_Checking_Enabled
75   --    Opt.No_Stdinc
76   --    Opt.No_Stdlib
77
78   procedure Gen_Or_Update_Object_File;
79   --  Is used to generate the object file (if generated directly by gnat1), or
80   --  update it if it has already been generated by the call to Call_Back_End,
81   --  so that its timestamp is updated by the call.
82   --
83   --  This is a no-op with the gcc back-end (the object file is generated by
84   --  the assembler afterwards), but is needed for back-ends that directly
85   --  generate the final object file so that the object file's timestamp is
86   --  correct when compared with the corresponding ali file by gnatmake.
87
88end Back_End;
89