gcc/ada/debug_a.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              D E B U G _ A                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2018, 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
  30 with Types; use Types;
  31
  32 package 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
  63 end Debug_A;