--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/eval_fat.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,116 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                             E V A L _ F A T                              --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--          Copyright (C) 1992-2012, 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.  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.          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This package provides for compile-time evaluation of static calls to the
+--  floating-point attribute functions. It is the compile-time equivalent of
+--  the System.Fat_Gen runtime package. The coding is quite similar, as are
+--  the subprogram specs, except that the type is passed as an explicit
+--  first parameter (and used via ttypes, to obtain the necessary information
+--  about the characteristics of the type for computing the results.
+
+with Types;  use Types;
+with Uintp;  use Uintp;
+with Urealp; use Urealp;
+
+package Eval_Fat is
+
+   subtype UI is Uint;
+   --  The compile time representation of universal integer
+
+   subtype T is Ureal;
+   --  The compile time representation of floating-point values
+
+   subtype R is Entity_Id;
+   --  The compile time representation of the floating-point root type
+
+   --  The following functions perform the operation implied by their name
+   --  which corresponds to the name of the attribute which they compute.
+   --  The arguments correspond to the attribute function arguments.
+
+   function Adjacent          (RT : R; X, Towards : T)              return T;
+
+   function Ceiling           (RT : R; X : T)                       return T;
+
+   function Compose           (RT : R; Fraction : T; Exponent : UI) return T;
+
+   function Copy_Sign         (RT : R; Value, Sign : T)             return T;
+
+   function Exponent          (RT : R; X : T)                       return UI;
+
+   function Floor             (RT : R; X : T)                       return T;
+
+   function Fraction          (RT : R; X : T)                       return T;
+
+   function Leading_Part      (RT : R; X : T; Radix_Digits : UI)    return T;
+
+   function Model             (RT : R; X : T)                       return T;
+
+   function Pred              (RT : R; X : T)                       return T;
+
+   function Remainder         (RT : R; X, Y : T)                    return T;
+
+   function Rounding          (RT : R; X : T)                       return T;
+
+   function Scaling           (RT : R; X : T; Adjustment : UI)      return T;
+
+   function Succ              (RT : R; X : T)                       return T;
+
+   function Truncation        (RT : R; X : T)                       return T;
+
+   function Unbiased_Rounding (RT : R; X : T)                       return T;
+
+   --  The following global declarations are used by the Machine attribute
+
+   type Rounding_Mode is (Floor, Ceiling, Round, Round_Even);
+   for Rounding_Mode use (0, 1, 2, 3);
+   --  Used to indicate rounding mode for Machine attribute
+   --  Note that C code in gigi knows that Round_Even is 3
+
+   --  The Machine attribute is special, in that it takes an extra argument
+   --  indicating the rounding mode, and also an argument Enode that is a
+   --  node used to post warnings (e.g. if asked to convert a negative zero
+   --  on a machine for which Signed_Zeros is False).
+
+   function Machine
+     (RT    : R;
+      X     : T;
+      Mode  : Rounding_Mode;
+      Enode : Node_Id) return T;
+
+   procedure Decompose_Int
+     (RT       : R;
+      X        : T;
+      Fraction : out UI;
+      Exponent : out UI;
+      Mode     : Rounding_Mode);
+   --  Decomposes a floating-point number into fraction and exponent parts.
+   --  The Fraction value returned is an integer representing the value
+   --  Fraction * Scale, where Scale is the value (Machine_Radix_Value (RT) **
+   --  Machine_Mantissa_Value (RT)). The value is obtained by using biased
+   --  rounding (halfway cases round away from zero), round to even, a floor
+   --  operation or a ceiling operation depending on the setting of Mode (see
+   --  corresponding descriptions in Urealp).
+
+end Eval_Fat;