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Diffstat (limited to 'gcc/ada/s-expmod.adb')
| -rw-r--r-- | gcc/ada/s-expmod.adb | 79 |
1 files changed, 0 insertions, 79 deletions
diff --git a/gcc/ada/s-expmod.adb b/gcc/ada/s-expmod.adb deleted file mode 100644 index aa1aa11c62f..00000000000 --- a/gcc/ada/s-expmod.adb +++ /dev/null @@ -1,79 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT RUN-TIME COMPONENTS -- --- -- --- S Y S T E M . E X P _ M O D -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2014, 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. -- --- -- --- As a special exception under Section 7 of GPL version 3, you are granted -- --- additional permissions described in the GCC Runtime Library Exception, -- --- version 3.1, as published by the Free Software Foundation. -- --- -- --- You should have received a copy of the GNU General Public License and -- --- a copy of the GCC Runtime Library Exception along with this program; -- --- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- --- <http://www.gnu.org/licenses/>. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -package body System.Exp_Mod is - use System.Unsigned_Types; - - ----------------- - -- Exp_Modular -- - ----------------- - - function Exp_Modular - (Left : Unsigned; - Modulus : Unsigned; - Right : Natural) return Unsigned - is - Result : Unsigned := 1; - Factor : Unsigned := Left; - Exp : Natural := Right; - - function Mult (X, Y : Unsigned) return Unsigned is - (Unsigned (Long_Long_Unsigned (X) * Long_Long_Unsigned (Y) - mod Long_Long_Unsigned (Modulus))); - -- Modular multiplication. Note that we can't take advantage of the - -- compiler's circuit, because the modulus is not known statically. - - begin - -- We use the standard logarithmic approach, Exp gets shifted right - -- testing successive low order bits and Factor is the value of the - -- base raised to the next power of 2. - - -- Note: it is not worth special casing the cases of base values -1,0,+1 - -- since the expander does this when the base is a literal, and other - -- cases will be extremely rare. - - if Exp /= 0 then - loop - if Exp rem 2 /= 0 then - Result := Mult (Result, Factor); - end if; - - Exp := Exp / 2; - exit when Exp = 0; - Factor := Mult (Factor, Factor); - end loop; - end if; - - return Result; - - end Exp_Modular; - -end System.Exp_Mod; |