------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- E V A L _ F A T -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2004 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 2, 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 COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- 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 Machine_Mantissa (RT : R) return Nat; function Machine_Radix (RT : R) return Nat; 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; end Eval_Fat;