| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . D O U B L E _ R E A L . P R O D U C T -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 2021-2022, 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. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This is the version of the separate package body for targets with an FMA |
| |
| separate (System.Double_Real) |
| |
| package body Product is |
| |
| function Fused_Multiply_Add (A, B, C : Num) return Num; |
| -- Return the result of A * B + C without intermediate rounding |
| |
| ------------------------ |
| -- Fused_Multiply_Add -- |
| ------------------------ |
| |
| function Fused_Multiply_Add (A, B, C : Num) return Num is |
| begin |
| case Num'Size is |
| when 32 => |
| declare |
| function Do_FMA (A, B, C : Num) return Num; |
| pragma Import (Intrinsic, Do_FMA, "__builtin_fmaf"); |
| |
| begin |
| return Do_FMA (A, B, C); |
| end; |
| |
| when 64 => |
| declare |
| function Do_FMA (A, B, C : Num) return Num; |
| pragma Import (Intrinsic, Do_FMA, "__builtin_fma"); |
| |
| begin |
| return Do_FMA (A, B, C); |
| end; |
| |
| when others => |
| raise Program_Error; |
| end case; |
| end Fused_Multiply_Add; |
| |
| -------------- |
| -- Two_Prod -- |
| -------------- |
| |
| function Two_Prod (A, B : Num) return Double_T is |
| P : constant Num := A * B; |
| |
| E : Num; |
| |
| begin |
| if Is_Infinity (P) or else Is_Zero (P) then |
| return (P, 0.0); |
| |
| else |
| E := Fused_Multiply_Add (A, B, -P); |
| |
| return (P, E); |
| end if; |
| end Two_Prod; |
| |
| ------------- |
| -- Two_Sqr -- |
| ------------- |
| |
| function Two_Sqr (A : Num) return Double_T is (Two_Prod (A, A)); |
| |
| end Product; |
