diff options
Diffstat (limited to 'gcc/ada/s-exnllf.adb')
| -rw-r--r-- | gcc/ada/s-exnllf.adb | 99 |
1 files changed, 97 insertions, 2 deletions
diff --git a/gcc/ada/s-exnllf.adb b/gcc/ada/s-exnllf.adb index c6765e8..a4386e8 100644 --- a/gcc/ada/s-exnllf.adb +++ b/gcc/ada/s-exnllf.adb @@ -6,7 +6,7 @@ -- -- -- B o d y -- -- -- --- Copyright (C) 1992-2012, Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2015, 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- -- @@ -29,8 +29,76 @@ -- -- ------------------------------------------------------------------------------ +-- Note: the reason for treating exponents in the range 0 .. 4 specially is +-- to ensure identical results to the static inline expansion in the case of +-- a compile time known exponent in this range. The use of Float'Machine and +-- Long_Float'Machine is to avoid unwanted extra precision in the results. + package body System.Exn_LLF is + function Exp + (Left : Long_Long_Float; + Right : Integer) return Long_Long_Float; + -- Common routine used if Right not in 0 .. 4 + + --------------- + -- Exn_Float -- + --------------- + + function Exn_Float + (Left : Float; + Right : Integer) return Float + is + Temp : Float; + begin + case Right is + when 0 => + return 1.0; + when 1 => + return Left; + when 2 => + return Float'Machine (Left * Left); + when 3 => + return Float'Machine (Left * Left * Left); + when 4 => + Temp := Float'Machine (Left * Left); + return Float'Machine (Temp * Temp); + when others => + return + Float'Machine + (Float (Exp (Long_Long_Float (Left), Right))); + end case; + end Exn_Float; + + -------------------- + -- Exn_Long_Float -- + -------------------- + + function Exn_Long_Float + (Left : Long_Float; + Right : Integer) return Long_Float + is + Temp : Long_Float; + begin + case Right is + when 0 => + return 1.0; + when 1 => + return Left; + when 2 => + return Long_Float'Machine (Left * Left); + when 3 => + return Long_Float'Machine (Left * Left * Left); + when 4 => + Temp := Long_Float'Machine (Left * Left); + return Long_Float'Machine (Temp * Temp); + when others => + return + Long_Float'Machine + (Long_Float (Exp (Long_Long_Float (Left), Right))); + end case; + end Exn_Long_Float; + ------------------------- -- Exn_Long_Long_Float -- ------------------------- @@ -39,6 +107,33 @@ package body System.Exn_LLF is (Left : Long_Long_Float; Right : Integer) return Long_Long_Float is + Temp : Long_Long_Float; + begin + case Right is + when 0 => + return 1.0; + when 1 => + return Left; + when 2 => + return Left * Left; + when 3 => + return Left * Left * Left; + when 4 => + Temp := Left * Left; + return Temp * Temp; + when others => + return Exp (Left, Right); + end case; + end Exn_Long_Long_Float; + + --------- + -- Exp -- + --------- + + function Exp + (Left : Long_Long_Float; + Right : Integer) return Long_Long_Float + is Result : Long_Long_Float := 1.0; Factor : Long_Long_Float := Left; Exp : Integer := Right; @@ -91,6 +186,6 @@ package body System.Exn_LLF is return 1.0 / Result; end; end if; - end Exn_Long_Long_Float; + end Exp; end System.Exn_LLF; |