--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnat/s-dwalin.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,191 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                   S Y S T E M . D W A R F _ L I N E S                    --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--           Copyright (C) 2009-2017, Free Software Foundation, Inc.        --
+--                                                                          --
+-- GNAT is free software;  you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
+-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
+--                                                                          --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception,   --
+-- version 3.1, as published by the Free Software Foundation.               --
+--                                                                          --
+-- You should have received a copy of the GNU General Public License and    --
+-- a copy of the GCC Runtime Library Exception along with this program;     --
+-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
+-- <http://www.gnu.org/licenses/>.                                          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This package provides routines to read DWARF line number information from
+--  a generic object file with as little overhead as possible. This allows
+--  conversions from PC addresses to human readable source locations.
+--
+--  Objects must be built with debugging information, however only the
+--  .debug_line section of the object file is referenced. In cases where object
+--  size is a consideration it's possible to strip all other .debug sections,
+--  which will decrease the size of the object significantly.
+
+pragma Polling (Off);
+--  We must turn polling off for this unit, because otherwise we can get
+--  elaboration circularities when polling is turned on
+
+with Ada.Exceptions.Traceback;
+
+with System.Object_Reader;
+with System.Storage_Elements;
+with System.Bounded_Strings;
+
+package System.Dwarf_Lines is
+
+   package AET renames Ada.Exceptions.Traceback;
+   package SOR renames System.Object_Reader;
+
+   type Dwarf_Context (In_Exception : Boolean := False) is private;
+   --  Type encapsulation the state of the Dwarf reader. When In_Exception
+   --  is True we are parsing as part of a exception handler decorator, we do
+   --  not want an exception to be raised, the parsing is done safely skipping
+   --  DWARF file that cannot be read or with stripped debug section for
+   --  example.
+
+   procedure Open
+     (File_Name :     String;
+      C         : out Dwarf_Context;
+      Success   : out Boolean);
+   procedure Close (C : in out Dwarf_Context);
+   --  Open and close files
+
+   procedure Set_Load_Address (C : in out Dwarf_Context; Addr : Address);
+   --  Set the load address of a file. This is used to rebase PIE (Position
+   --  Independant Executable) binaries.
+
+   function Is_Inside (C : Dwarf_Context; Addr : Address) return Boolean;
+   pragma Inline (Is_Inside);
+   --  Return true iff Addr is within the module
+
+   function Low (C : Dwarf_Context) return Address;
+   pragma Inline (Low);
+   --  Return the lowest address of C
+
+   procedure Dump (C : in out Dwarf_Context);
+   --  Dump each row found in the object's .debug_lines section to standard out
+
+   procedure Dump_Cache (C : Dwarf_Context);
+   --  Dump the cache (if present)
+
+   procedure Enable_Cache (C : in out Dwarf_Context);
+   --  Read symbols information to speed up Symbolic_Traceback.
+
+   procedure Symbolic_Traceback
+     (Cin          :        Dwarf_Context;
+      Traceback    :        AET.Tracebacks_Array;
+      Suppress_Hex :        Boolean;
+      Symbol_Found : in out Boolean;
+      Res          : in out System.Bounded_Strings.Bounded_String);
+   --  Generate a string for a traceback suitable for displaying to the user.
+   --  If one or more symbols are found, Symbol_Found is set to True. This
+   --  allows the caller to fall back to hexadecimal addresses.
+
+   Dwarf_Error : exception;
+   --  Raised if a problem is encountered parsing DWARF information. Can be a
+   --  result of a logic error or malformed DWARF information.
+
+private
+   --  The following section numbers reference
+
+   --    "DWARF Debugging Information Format, Version 3"
+
+   --  published by the Standards Group, http://freestandards.org.
+
+   --  6.2.2 State Machine Registers
+
+   type Line_Info_Registers is record
+      Address        : SOR.uint64;
+      File           : SOR.uint32;
+      Line           : SOR.uint32;
+      Column         : SOR.uint32;
+      Is_Stmt        : Boolean;
+      Basic_Block    : Boolean;
+      End_Sequence   : Boolean;
+      Prologue_End   : Boolean;
+      Epilogue_Begin : Boolean;
+      ISA            : SOR.uint32;
+      Is_Row         : Boolean;
+   end record;
+
+   --  6.2.4 The Line Number Program Prologue
+
+   MAX_OPCODE_LENGTHS : constant := 256;
+
+   type Opcodes_Lengths_Array is
+     array (SOR.uint32 range 1 .. MAX_OPCODE_LENGTHS) of SOR.uint8;
+
+   type Line_Info_Prologue is record
+      Unit_Length       : SOR.uint32;
+      Version           : SOR.uint16;
+      Prologue_Length   : SOR.uint32;
+      Min_Isn_Length    : SOR.uint8;
+      Default_Is_Stmt   : SOR.uint8;
+      Line_Base         : SOR.int8;
+      Line_Range        : SOR.uint8;
+      Opcode_Base       : SOR.uint8;
+      Opcode_Lengths    : Opcodes_Lengths_Array;
+      Includes_Offset   : SOR.Offset;
+      File_Names_Offset : SOR.Offset;
+   end record;
+
+   type Search_Entry is record
+      First : SOR.uint32;
+      Size  : SOR.uint32;
+      --  Function bounds as offset to the base address.
+
+      Sym : SOR.uint32;
+      --  Symbol offset to get the name.
+
+      Line : SOR.uint32;
+      --  Dwarf line offset.
+   end record;
+
+   type Search_Array is array (Natural range <>) of Search_Entry;
+
+   type Search_Array_Access is access Search_Array;
+
+   type Dwarf_Context (In_Exception : Boolean := False) is record
+      Load_Slide : System.Storage_Elements.Integer_Address := 0;
+      Low, High  : Address;
+      --  Bounds of the module
+
+      Obj : SOR.Object_File_Access;
+      --  The object file containing dwarf sections
+
+      Has_Debug : Boolean;
+      --  True if all debug sections are available
+
+      Cache : Search_Array_Access;
+      --  Quick access to symbol and debug info (when present).
+
+      Lines   : SOR.Mapped_Stream;
+      Aranges : SOR.Mapped_Stream;
+      Info    : SOR.Mapped_Stream;
+      Abbrev  : SOR.Mapped_Stream;
+      --  Dwarf line, aranges, info and abbrev sections
+
+      Prologue      : Line_Info_Prologue;
+      Registers     : Line_Info_Registers;
+      Next_Prologue : SOR.Offset;
+      --  State for lines
+   end record;
+
+end System.Dwarf_Lines;