gcc/ada/debug_a.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              D E B U G _ A                               --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   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 with Atree;   use Atree;
  27 with Debug;   use Debug;
  28 with Sinfo;   use Sinfo;
  29 with Sinput;  use Sinput;
  30 with Output;  use Output;
  31
  32 package body Debug_A is
  33
  34    Debug_A_Depth : Natural := 0;
  35    --  Output for the debug A flag is preceded by a sequence of vertical bar
  36    --  characters corresponding to the recursion depth of the actions being
  37    --  recorded (analysis, expansion, resolution and evaluation of nodes)
  38    --  This variable records the depth.
  39
  40    Max_Node_Ids : constant := 200;
  41    --  Maximum number of Node_Id values that get stacked
  42
  43    Node_Ids : array (1 .. Max_Node_Ids) of Node_Id;
  44    --  A stack used to keep track of Node_Id values for setting the value of
  45    --  Current_Error_Node correctly. Note that if we have more than 200
  46    --  recursion levels, we just don't reset the right value on exit, which
  47    --  is not crucial, since this is only for debugging.
  48
  49    -----------------------
  50    -- Local Subprograms --
  51    -----------------------
  52
  53    procedure Debug_Output_Astring;
  54    --  Outputs Debug_A_Depth number of vertical bars, used to preface messages
  55
  56    -------------------
  57    -- Debug_A_Entry --
  58    -------------------
  59
  60    procedure Debug_A_Entry (S : String; N : Node_Id) is
  61    begin
  62       --  Output debugging information if -gnatda flag set
  63
  64       if Debug_Flag_A then
  65          Debug_Output_Astring;
  66          Write_Str (S);
  67          Write_Str ("Node_Id = ");
  68          Write_Int (Int (N));
  69          Write_Str ("  ");
  70          Write_Location (Sloc (N));
  71          Write_Str ("  ");
  72          Write_Str (Node_Kind'Image (Nkind (N)));
  73          Write_Eol;
  74       end if;
  75
  76       --  Now push the new element
  77
  78       --  Why is this done unconditionally???
  79
  80       Debug_A_Depth := Debug_A_Depth + 1;
  81
  82       if Debug_A_Depth <= Max_Node_Ids then
  83          Node_Ids (Debug_A_Depth) := N;
  84       end if;
  85
  86       --  Set Current_Error_Node only if the new node has a decent Sloc
  87       --  value, since it is for the Sloc value that we set this anyway.
  88       --  If we don't have a decent Sloc value, we leave it unchanged.
  89
  90       if Sloc (N) > No_Location then
  91          Current_Error_Node := N;
  92       end if;
  93    end Debug_A_Entry;
  94
  95    ------------------
  96    -- Debug_A_Exit --
  97    ------------------
  98
  99    procedure Debug_A_Exit (S : String; N : Node_Id; Comment : String) is
 100    begin
 101       Debug_A_Depth := Debug_A_Depth - 1;
 102
 103       --  We look down the stack to find something with a decent Sloc. (If
 104       --  we find nothing, just leave it unchanged which is not so terrible)
 105
 106       --  This seems nasty overhead for the normal case ???
 107
 108       for J in reverse 1 .. Integer'Min (Max_Node_Ids, Debug_A_Depth) loop
 109          if Sloc (Node_Ids (J)) > No_Location then
 110             Current_Error_Node := Node_Ids (J);
 111             exit;
 112          end if;
 113       end loop;
 114
 115       --  Output debugging information if -gnatda flag set
 116
 117       if Debug_Flag_A then
 118          Debug_Output_Astring;
 119          Write_Str (S);
 120          Write_Str ("Node_Id = ");
 121          Write_Int (Int (N));
 122          Write_Str (Comment);
 123          Write_Eol;
 124       end if;
 125    end Debug_A_Exit;
 126
 127    --------------------------
 128    -- Debug_Output_Astring --
 129    --------------------------
 130
 131    procedure Debug_Output_Astring is
 132       Vbars : constant String := "|||||||||||||||||||||||||";
 133       --  Should be constant, removed because of GNAT 1.78 bug ???
 134
 135    begin
 136       if Debug_A_Depth > Vbars'Length then
 137          for I in Vbars'Length .. Debug_A_Depth loop
 138             Write_Char ('|');
 139          end loop;
 140
 141          Write_Str (Vbars);
 142
 143       else
 144          Write_Str (Vbars (1 .. Debug_A_Depth));
 145       end if;
 146    end Debug_Output_Astring;
 147
 148 end Debug_A;