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Diffstat (limited to 'gcc-4.2.1/gcc/ada/s-fatgen.ads')
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diff --git a/gcc-4.2.1/gcc/ada/s-fatgen.ads b/gcc-4.2.1/gcc/ada/s-fatgen.ads new file mode 100644 index 000000000..83b6f0644 --- /dev/null +++ b/gcc-4.2.1/gcc/ada/s-fatgen.ads @@ -0,0 +1,131 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S Y S T E M . F A T _ G E N -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2005 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, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This generic package provides a target independent implementation of the +-- floating-point attributes that denote functions. The implementations here +-- are portable, but very slow. The runtime contains a set of instantiations +-- of this package for all predefined floating-point types, and these should +-- be replaced by efficient assembly language code where possible. + +generic + type T is digits <>; + +package System.Fat_Gen is + pragma Pure; + + subtype UI is Integer; + -- The runtime representation of universal integer for the purposes of + -- this package is integer. The expander generates conversions for the + -- actual type used. For functions returning universal integer, there + -- is no problem, since the result always is in range of integer. For + -- input arguments, the expander has to do some special casing to deal + -- with the (very annoying!) cases of out of range values. If we used + -- Long_Long_Integer to represent universal, then there would be no + -- problem, but the resulting inefficiency would be annoying. + + function Adjacent (X, Towards : T) return T; + + function Ceiling (X : T) return T; + + function Compose (Fraction : T; Exponent : UI) return T; + + function Copy_Sign (Value, Sign : T) return T; + + function Exponent (X : T) return UI; + + function Floor (X : T) return T; + + function Fraction (X : T) return T; + + function Leading_Part (X : T; Radix_Digits : UI) return T; + + function Machine (X : T) return T; + + function Machine_Rounding (X : T) return T; + + function Model (X : T) return T; + + function Pred (X : T) return T; + + function Remainder (X, Y : T) return T; + + function Rounding (X : T) return T; + + function Scaling (X : T; Adjustment : UI) return T; + + function Succ (X : T) return T; + + function Truncation (X : T) return T; + + function Unbiased_Rounding (X : T) return T; + + function Valid (X : access T) return Boolean; + -- This function checks if the object of type T referenced by X + -- is valid, and returns True/False accordingly. The parameter is + -- passed by reference (access) here, as the object of type T may + -- be an abnormal value that cannot be passed in a floating-point + -- register, and the whole point of 'Valid is to prevent exceptions. + -- Note that the object of type T must have the natural alignment + -- for type T. See Unaligned_Valid for further discussion. + -- + -- Note: this routine does not work for Vax_Float ??? + + function Unaligned_Valid (A : System.Address) return Boolean; + -- This version of Valid is used if the floating-point value to + -- be checked is not known to be aligned (for example it appears + -- in a packed record). In this case, we cannot call Valid since + -- Valid assumes proper full alignment. Instead Unaligned_Valid + -- performs the same processing for a possibly unaligned float, + -- by first doing a copy and then calling Valid. One might think + -- that the front end could simply do a copy to an aligned temp, + -- but remember that we may have an abnormal value that cannot + -- be copied into a floating-point register, so things are a bit + -- trickier than one might expect. + -- + -- Note: Unaligned_Valid is never called for a target which does + -- not require strict alignment (e.g. the ia32/x86), since on a + -- target not requiring strict alignment, it is fine to pass a + -- non-aligned value to the standard Valid routine. + -- + -- Note: this routine does not work for Vax_Float ??? + +private + pragma Inline (Machine); + pragma Inline (Model); + + -- Note: previously the validity checking subprograms (Unaligned_Valid and + -- Valid) were also inlined, but this was changed since there were some + -- problems with this inlining in optimized mode, and in any case it seems + -- better to avoid this inlining (space and robustness considerations). + +end System.Fat_Gen; |