1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              D E B U G _ A                               --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2007, 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--  This package contains data and subprograms to support the A debug switch
27--  that is used to generate output showing what node is being analyzed,
28--  resolved, evaluated, or expanded.
29
30with Types; use Types;
31
32package Debug_A is
33
34   --  Note: the following subprograms are used in a stack like manner, with
35   --  an exit call matching each entry call. This means that they can keep
36   --  track of the current node being worked on, with the entry call setting
37   --  a new value, by pushing the Node_Id value on a stack, and the exit call
38   --  popping this value off. Atree.Current_Error_Node is set by both the
39   --  entry and exit routines to point to the current node so that an abort
40   --  message indicates the node involved as accurately as possible.
41
42   procedure Debug_A_Entry (S : String; N : Node_Id);
43   pragma Inline (Debug_A_Entry);
44   --  Generates a message prefixed by a sequence of bars showing the nesting
45   --  depth (depth increases by 1 for a Debug_A_Entry call and is decreased
46   --  by the corresponding Debug_A_Exit call). Then the string is output
47   --  (analyzing, expanding etc), followed by the node number and its kind.
48   --  This output is generated only if the debug A flag is set. If the debug
49   --  A flag is not set, then no output is generated. This call also sets the
50   --  Node_Id value in Atree.Current_Error_Node in case a bomb occurs. This
51   --  is done unconditionally, whether or not the debug A flag is set.
52
53   procedure Debug_A_Exit (S : String; N : Node_Id; Comment : String);
54   pragma Inline (Debug_A_Exit);
55   --  Generates the corresponding termination message. The message is preceded
56   --  by a sequence of bars, followed by the string S, the node number, and
57   --  a trailing comment (e.g. " (already evaluated)"). This output is
58   --  generated only if the debug A flag is set. If the debug A flag is not
59   --  set, then no output is generated. This call also resets the value in
60   --  Atree.Current_Error_Node to what it was before the corresponding call
61   --  to Debug_A_Entry.
62
63end Debug_A;
64