gcc/ada/5amastop.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                     SYSTEM.MACHINE_STATE_OPERATIONS                      --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                         (Version for Alpha/Dec Unix)                     --
   9 --                                                                          --
  10 --                            $Revision: 1.5 $
  11 --                                                                          --
  12 --           Copyright (C) 1999-2001 Ada Core Technologies, Inc.            --
  13 --                                                                          --
  14 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  15 -- terms of the  GNU General Public License as published  by the Free Soft- --
  16 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  17 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  18 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  19 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  20 -- for  more details.  You should have  received  a copy of the GNU General --
  21 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  22 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  23 -- MA 02111-1307, USA.                                                      --
  24 --                                                                          --
  25 -- As a special exception,  if other files  instantiate  generics from this --
  26 -- unit, or you link  this unit with other files  to produce an executable, --
  27 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  28 -- covered  by the  GNU  General  Public  License.  This exception does not --
  29 -- however invalidate  any other reasons why  the executable file  might be --
  30 -- covered by the  GNU Public License.                                      --
  31 --                                                                          --
  32 -- GNAT was originally developed  by the GNAT team at  New York University. --
  33 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  34 --                                                                          --
  35 ------------------------------------------------------------------------------
  36
  37 --  This version of System.Machine_State_Operations is for use on
  38 --  Alpha systems running DEC Unix.
  39
  40 with System.Memory;
  41
  42 package body System.Machine_State_Operations is
  43
  44    use System.Exceptions;
  45
  46    pragma Linker_Options ("-lexc");
  47    --  Needed for definitions of exc_capture_context and exc_virtual_unwind
  48
  49    ----------------------------
  50    -- Allocate_Machine_State --
  51    ----------------------------
  52
  53    function Allocate_Machine_State return Machine_State is
  54       use System.Storage_Elements;
  55
  56       function c_machine_state_length return Storage_Offset;
  57       pragma Import (C, c_machine_state_length, "__gnat_machine_state_length");
  58
  59    begin
  60       return Machine_State
  61         (Memory.Alloc (Memory.size_t (c_machine_state_length)));
  62    end Allocate_Machine_State;
  63
  64    -------------------
  65    -- Enter_Handler --
  66    -------------------
  67
  68    procedure Enter_Handler (M : Machine_State; Handler : Handler_Loc) is
  69       procedure c_enter_handler (M : Machine_State; Handler : Handler_Loc);
  70       pragma Import (C, c_enter_handler, "__gnat_enter_handler");
  71
  72    begin
  73       c_enter_handler (M, Handler);
  74    end Enter_Handler;
  75
  76    ----------------
  77    -- Fetch_Code --
  78    ----------------
  79
  80    function Fetch_Code (Loc : Code_Loc) return Code_Loc is
  81    begin
  82       return Loc;
  83    end Fetch_Code;
  84
  85    ------------------------
  86    -- Free_Machine_State --
  87    ------------------------
  88
  89    procedure Free_Machine_State (M : in out Machine_State) is
  90       procedure Gnat_Free (M : in Machine_State);
  91       pragma Import (C, Gnat_Free, "__gnat_free");
  92
  93    begin
  94       Gnat_Free (M);
  95       M := Machine_State (Null_Address);
  96    end Free_Machine_State;
  97
  98    ------------------
  99    -- Get_Code_Loc --
 100    ------------------
 101
 102    function Get_Code_Loc (M : Machine_State) return Code_Loc is
 103       Asm_Call_Size : constant := 4;
 104
 105       function c_get_code_loc (M : Machine_State) return Code_Loc;
 106       pragma Import (C, c_get_code_loc, "__gnat_get_code_loc");
 107
 108       --  Code_Loc returned by c_get_code_loc is the return point but here we
 109       --  want Get_Code_Loc to return the call point. Under DEC Unix a call
 110       --  asm instruction takes 4 bytes. So we must remove this value from
 111       --  c_get_code_loc to have the call point.
 112
 113    begin
 114       return c_get_code_loc (M) - Asm_Call_Size;
 115    end Get_Code_Loc;
 116
 117    --------------------------
 118    -- Machine_State_Length --
 119    --------------------------
 120
 121    function Machine_State_Length
 122      return System.Storage_Elements.Storage_Offset
 123    is
 124       use System.Storage_Elements;
 125
 126       function c_machine_state_length return Storage_Offset;
 127       pragma Import (C, c_machine_state_length, "__gnat_machine_state_length");
 128
 129    begin
 130       return c_machine_state_length;
 131    end Machine_State_Length;
 132
 133    ---------------
 134    -- Pop_Frame --
 135    ---------------
 136
 137    procedure Pop_Frame
 138      (M    : Machine_State;
 139       Info : Subprogram_Info_Type)
 140    is
 141       procedure exc_virtual_unwind
 142         (Fcn  : System.Address;
 143          M    : Machine_State);
 144       pragma Import (C, exc_virtual_unwind, "exc_virtual_unwind");
 145
 146    begin
 147       exc_virtual_unwind (System.Null_Address, M);
 148    end Pop_Frame;
 149
 150    -----------------------
 151    -- Set_Machine_State --
 152    -----------------------
 153
 154    procedure Set_Machine_State (M : Machine_State) is
 155       procedure c_capture_context (M : Machine_State);
 156       pragma Import (C, c_capture_context, "exc_capture_context");
 157
 158    begin
 159       c_capture_context (M);
 160       Pop_Frame (M, System.Null_Address);
 161    end Set_Machine_State;
 162
 163    ------------------------------
 164    -- Set_Signal_Machine_State --
 165    ------------------------------
 166
 167    procedure Set_Signal_Machine_State
 168      (M       : Machine_State;
 169       Context : System.Address) is
 170    begin
 171       null;
 172    end Set_Signal_Machine_State;
 173
 174 end System.Machine_State_Operations;