| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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; |
