Add minimal GNAT run time system (RTS)

Add a stripped-down version of libgnat. This is somehow comparable to
libgcc but for Ada programs. It's licensed under GPLv3 but with the
runtime library exception. So it's totally fine to link it with our
GPLv2 code and keep it under GPLv2.

Change-Id: Ie6522abf093f0a516b9ae18ddc69131bd721dc0c
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/11836
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>

1 files changed, 117 insertions, 0 deletions

diff --git a/src/lib/gnat/s-stoele.ads b/src/lib/gnat/s-stoele.ads
new file mode 100644
index 0000000000..bf773cb03d
--- /dev/null
+++ b/src/lib/gnat/s-stoele.ads
@@ -0,0 +1,117 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--               S Y S T E M . S T O R A G E _ E L E M E N T S              --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--          Copyright (C) 2002-2013, Free Software Foundation, Inc.         --
+--                                                                          --
+-- This specification is derived from the Ada Reference Manual for use with --
+-- GNAT. The copyright notice above, and the license provisions that follow --
+-- apply solely to the implementation dependent sections of this file.      --
+--                                                                          --
+-- 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.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  Warning: declarations in this package are ambiguous with respect to the
+--  extra declarations that can be introduced into System using Extend_System.
+--  It is a good idea to avoid use clauses for this package.
+
+pragma Compiler_Unit_Warning;
+
+package System.Storage_Elements is
+   pragma Pure;
+   --  Note that we take advantage of the implementation permission to make
+   --  this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada 2005,
+   --  this is Pure in any case (AI-362).
+
+   --  We also add the pragma Pure_Function to the operations in this package,
+   --  because otherwise functions with parameters derived from Address are
+   --  treated as non-pure by the back-end (see exp_ch6.adb). This is because
+   --  in many cases such a parameter is used to hide read/out access to
+   --  objects, and it would be unsafe to treat such functions as pure.
+
+   type Storage_Offset is range
+     -(2 ** (Integer'(Standard'Address_Size) - 1)) ..
+     +(2 ** (Integer'(Standard'Address_Size) - 1)) - Long_Long_Integer'(1);
+   --  Note: the reason for the Long_Long_Integer qualification here is to
+   --  avoid a bogus ambiguity when this unit is analyzed in an rtsfind
+   --  context. It may be possible to remove this in the future, but it is
+   --  certainly harmless in any case ???
+
+   subtype Storage_Count is Storage_Offset range 0 .. Storage_Offset'Last;
+
+   type Storage_Element is mod 2 ** Storage_Unit;
+   for Storage_Element'Size use Storage_Unit;
+
+   pragma Universal_Aliasing (Storage_Element);
+   --  This type is used by the expander to implement aggregate copy
+
+   type Storage_Array is
+     array (Storage_Offset range <>) of aliased Storage_Element;
+   for Storage_Array'Component_Size use Storage_Unit;
+
+   --  Address arithmetic
+
+   function "+" (Left : Address; Right : Storage_Offset) return Address;
+   pragma Convention (Intrinsic, "+");
+   pragma Inline_Always ("+");
+   pragma Pure_Function ("+");
+
+   function "+" (Left : Storage_Offset; Right : Address) return Address;
+   pragma Convention (Intrinsic, "+");
+   pragma Inline_Always ("+");
+   pragma Pure_Function ("+");
+
+   function "-" (Left : Address; Right : Storage_Offset) return Address;
+   pragma Convention (Intrinsic, "-");
+   pragma Inline_Always ("-");
+   pragma Pure_Function ("-");
+
+   function "-" (Left, Right : Address) return Storage_Offset;
+   pragma Convention (Intrinsic, "-");
+   pragma Inline_Always ("-");
+   pragma Pure_Function ("-");
+
+   function "mod"
+     (Left  : Address;
+      Right : Storage_Offset) return  Storage_Offset;
+   pragma Convention (Intrinsic, "mod");
+   pragma Inline_Always ("mod");
+   pragma Pure_Function ("mod");
+
+   --  Conversion to/from integers
+
+   type Integer_Address is mod Memory_Size;
+
+   function To_Address (Value : Integer_Address) return Address;
+   pragma Convention (Intrinsic, To_Address);
+   pragma Inline_Always (To_Address);
+   pragma Pure_Function (To_Address);
+
+   function To_Integer (Value : Address) return Integer_Address;
+   pragma Convention (Intrinsic, To_Integer);
+   pragma Inline_Always (To_Integer);
+   pragma Pure_Function (To_Integer);
+
+end System.Storage_Elements;