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diff --git a/gcc/ada/s-arit64.ads b/gcc/ada/s-arit64.ads new file mode 100644 index 00000000000..d32bbaab2a5 --- /dev/null +++ b/gcc/ada/s-arit64.ads @@ -0,0 +1,84 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S Y S T E M . A R I T H _ 6 4 -- +-- -- +-- S p e c -- +-- -- +-- $Revision: 1.7 $ -- +-- -- +-- Copyright (C) 1994,1995,1996 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. -- +-- -- +-- 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. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +-- This unit provides software routines for doing arithmetic on 64-bit +-- signed integer values in cases where either overflow checking is +-- required, or intermediate results are longer than 64 bits. + +with Interfaces; + +package System.Arith_64 is +pragma Pure (Arith_64); + + subtype Int64 is Interfaces.Integer_64; + + function Add_With_Ovflo_Check (X, Y : Int64) return Int64; + -- Raises Constraint_Error if sum of operands overflows 64 bits, + -- otherwise returns the 64-bit signed integer sum. + + function Subtract_With_Ovflo_Check (X, Y : Int64) return Int64; + -- Raises Constraint_Error if difference of operands overflows 64 + -- bits, otherwise returns the 64-bit signed integer difference. + + function Multiply_With_Ovflo_Check (X, Y : Int64) return Int64; + -- Raises Constraint_Error if product of operands overflows 64 + -- bits, otherwise returns the 64-bit signed integer difference. + + procedure Scaled_Divide + (X, Y, Z : Int64; + Q, R : out Int64; + Round : Boolean); + -- Performs the division of (X * Y) / Z, storing the quotient in Q + -- and the remainder in R. Constraint_Error is raised if Z is zero, + -- or if the quotient does not fit in 64-bits. Round indicates if + -- the result should be rounded. If Round is False, then Q, R are + -- the normal quotient and remainder from a truncating division. + -- If Round is True, then Q is the rounded quotient. the remainder + -- R is not affected by the setting of the Round flag. + + procedure Double_Divide + (X, Y, Z : Int64; + Q, R : out Int64; + Round : Boolean); + -- Performs the division X / (Y * Z), storing the quotient in Q and + -- the remainder in R. Constraint_Error is raised if Y or Z is zero. + -- Round indicates if the result should be rounded. If Round is False, + -- then Q, R are the normal quotient and remainder from a truncating + -- division. If Round is True, then Q is the rounded quotient. The + -- remainder R is not affected by the setting of the Round flag. The + -- result is known to be in range except for the noted possibility of + -- Y or Z being zero, so no other overflow checks are required. + +end System.Arith_64; |