--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/adabkend.adb	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,290 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                             A D A B K E N D                              --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--                     Copyright (C) 2001-2017, AdaCore                     --
+--                                                                          --
+-- 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.  See the GNU General Public License --
+-- for  more details.  You should have  received  a copy of the GNU General --
+-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
+-- http://www.gnu.org/licenses for a complete copy of the license.          --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This is the version of the Back_End package for back ends written in Ada
+
+with Atree;    use Atree;
+with Debug;
+with Lib;
+with Opt;      use Opt;
+with Output;   use Output;
+with Osint;    use Osint;
+with Osint.C;  use Osint.C;
+with Switch.C; use Switch.C;
+with Types;    use Types;
+
+with System.OS_Lib; use System.OS_Lib;
+
+package body Adabkend is
+
+   use Switch;
+
+   -------------------
+   -- Call_Back_End --
+   -------------------
+
+   procedure Call_Back_End is
+   begin
+      if (Opt.Verbose_Mode or Opt.Full_List)
+        and then not Debug.Debug_Flag_7
+      then
+         Write_Eol;
+         Write_Str (Product_Name);
+         Write_Str (", Copyright ");
+         Write_Str (Copyright_Years);
+         Write_Str (" Ada Core Technologies, Inc.");
+         Write_Str (" (http://www.adacore.com)");
+         Write_Eol;
+         Write_Eol;
+      end if;
+
+      --  The front end leaves the Current_Error_Node at a location that is
+      --  meaningless and confusing when emitting bug boxes from the back end.
+      --  Reset the global variable in order to emit "No source file position
+      --  information available" messages on back end crashes.
+
+      Current_Error_Node := Empty;
+
+      Driver (Lib.Cunit (Types.Main_Unit));
+   end Call_Back_End;
+
+   ------------------------
+   -- Scan_Compiler_Args --
+   ------------------------
+
+   procedure Scan_Compiler_Arguments is
+      Output_File_Name_Seen : Boolean := False;
+      --  Set to True after having scanned the file_name for switch
+      --  "-gnatO file_name"
+
+      Argument_Count : constant Integer := Arg_Count - 1;
+      --  Number of arguments (excluding program name)
+
+      Args     : Argument_List (1 .. Argument_Count);
+      Next_Arg : Positive := 1;
+
+      procedure Scan_Back_End_Switches (Switch_Chars : String);
+      --  Procedure to scan out switches stored in Switch_Chars. The first
+      --  character is known to be a valid switch character, and there are no
+      --  blanks or other switch terminator characters in the string, so the
+      --  entire string should consist of valid switch characters, except that
+      --  an optional terminating NUL character is allowed.
+      --
+      --  If the switch is not valid, control will not return. The switches
+      --  must still be scanned to skip the "-o" arguments, or internal GCC
+      --  switches, which may be safely ignored by other back ends.
+
+      ----------------------------
+      -- Scan_Back_End_Switches --
+      ----------------------------
+
+      procedure Scan_Back_End_Switches (Switch_Chars : String) is
+         First : constant Positive := Switch_Chars'First + 1;
+         Last  : constant Natural  := Switch_Last (Switch_Chars);
+
+      begin
+         --  Process any back end switches, returning if the switch does not
+         --  affect code generation or falling through if it does, so the
+         --  switch will get stored.
+
+         --  Skip -o, -G or internal GCC switches together with their argument.
+
+         if Switch_Chars (First .. Last) = "o"
+           or else Switch_Chars (First .. Last) = "G"
+           or else Is_Internal_GCC_Switch (Switch_Chars)
+         then
+            Next_Arg := Next_Arg + 1;
+            return; -- ignore this switch
+
+         --  Set optimization indicators appropriately. In gcc-based GNAT this
+         --  is picked up from imported variables set by the gcc driver, but
+         --  for compilers with non-gcc back ends we do it here to allow use
+         --  of these switches by the front end. Allowed optimization switches
+         --  are -Os (optimize for size), -O[0123], and -O (same as -O1).
+
+         elsif Switch_Chars (First) = 'O' then
+            if First = Last then
+               Optimization_Level := 1;
+
+            elsif Last - First = 1 then
+               if Switch_Chars (Last) = 's' then
+                  Optimize_Size := 1;
+                  Optimization_Level := 2;  -- Consistent with gcc setting
+
+               elsif Switch_Chars (Last) in '0' .. '3' then
+                  Optimization_Level :=
+                    Character'Pos (Switch_Chars (Last)) - Character'Pos ('0');
+
+               else
+                  Fail ("invalid switch: " & Switch_Chars);
+               end if;
+
+            else
+               Fail ("invalid switch: " & Switch_Chars);
+            end if;
+
+         elsif Switch_Chars (First .. Last) = "quiet" then
+            return; -- ignore this switch
+
+         elsif Switch_Chars (First .. Last) = "c" then
+            return; -- ignore this switch
+
+         --  The -x switch and its language name argument will generally be
+         --  ignored by non-gcc back ends. In any case, we save the switch and
+         --  argument in the compilation switches.
+
+         elsif Switch_Chars (First .. Last) = "x" then
+            Lib.Store_Compilation_Switch (Switch_Chars);
+            Next_Arg := Next_Arg + 1;
+
+            declare
+               Argv : constant String := Args (Next_Arg).all;
+
+            begin
+               if Is_Switch (Argv) then
+                  Fail ("language name missing after -x");
+               else
+                  Lib.Store_Compilation_Switch (Argv);
+               end if;
+            end;
+
+            return;
+
+         --  Special check, the back end switch -fno-inline also sets the
+         --  front end flags to entirely inhibit all inlining. So we store it
+         --  and set the appropriate flags.
+
+         elsif Switch_Chars (First .. Last) = "fno-inline" then
+            Lib.Store_Compilation_Switch (Switch_Chars);
+            Opt.Disable_FE_Inline := True;
+            Opt.Disable_FE_Inline_Always := True;
+            return;
+
+         --  Similar processing for -fpreserve-control-flow
+
+         elsif Switch_Chars (First .. Last) = "fpreserve-control-flow" then
+            Lib.Store_Compilation_Switch (Switch_Chars);
+            Opt.Suppress_Control_Flow_Optimizations := True;
+            return;
+
+         --  Ignore all other back end switches
+
+         elsif Is_Back_End_Switch (Switch_Chars) then
+            null;
+
+         --  Give error for junk switch
+
+         else
+            Fail ("invalid switch: " & Switch_Chars);
+         end if;
+
+         --  Store any other GCC switches
+
+         Lib.Store_Compilation_Switch (Switch_Chars);
+      end Scan_Back_End_Switches;
+
+   --  Start of processing for Scan_Compiler_Args
+
+   begin
+      --  Put all the arguments in argument list Args
+
+      for Arg in 1 .. Argument_Count loop
+         declare
+            Argv : String (1 .. Len_Arg (Arg));
+         begin
+            Fill_Arg (Argv'Address, Arg);
+            Args (Arg) := new String'(Argv);
+         end;
+      end loop;
+
+      --  Loop through command line arguments, storing them for later access
+
+      while Next_Arg <= Argument_Count loop
+         Look_At_Arg : declare
+            Argv : constant String := Args (Next_Arg).all;
+
+         begin
+            if Argv'Length = 0 then
+               Fail ("Empty argument");
+            end if;
+
+            --  If the previous switch has set the Output_File_Name_Present
+            --  flag (that is we have seen a -gnatO), then the next argument
+            --  is the name of the output object file.
+
+            if Opt.Output_File_Name_Present
+              and then not Output_File_Name_Seen
+            then
+               if Is_Switch (Argv) then
+                  Fail ("Object file name missing after -gnatO");
+               else
+                  Set_Output_Object_File_Name (Argv);
+                  Output_File_Name_Seen := True;
+               end if;
+
+               --  If the previous switch has set the Search_Directory_Present
+               --  flag (that is if we have just seen -I), then the next
+               --  argument is a search directory path.
+
+            elsif Search_Directory_Present then
+               if Is_Switch (Argv) then
+                  Fail ("search directory missing after -I");
+               else
+                  Add_Src_Search_Dir (Argv);
+
+                  --  Add directory to lib search so that back end can take as
+                  --  input ALI files if needed. Otherwise this won't have any
+                  --  impact on the compiler.
+
+                  Add_Lib_Search_Dir (Argv);
+
+                  Search_Directory_Present := False;
+               end if;
+
+            --  If not a switch, must be a file name
+
+            elsif not Is_Switch (Argv) then
+               Add_File (Argv);
+
+            --  We must recognize -nostdinc to suppress visibility on the
+            --  standard GNAT RTL sources.
+
+            elsif Argv (Argv'First + 1 .. Argv'Last) = "nostdinc" then
+               Opt.No_Stdinc := True;
+
+            --  Front end switch
+
+            elsif Is_Front_End_Switch (Argv) then
+               Scan_Front_End_Switches (Argv, Args, Next_Arg);
+
+            --  All non-front-end switches are back-end switches
+
+            else
+               Scan_Back_End_Switches (Argv);
+            end if;
+         end Look_At_Arg;
+
+         Next_Arg := Next_Arg + 1;
+      end loop;
+   end Scan_Compiler_Arguments;
+
+end Adabkend;