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Diffstat (limited to 'math/mul_split.h')
-rw-r--r-- | math/mul_split.h | 50 |
1 files changed, 0 insertions, 50 deletions
diff --git a/math/mul_split.h b/math/mul_split.h deleted file mode 100644 index 7e68e33b03..0000000000 --- a/math/mul_split.h +++ /dev/null @@ -1,50 +0,0 @@ -/* Compute full X * Y for double type. - Copyright (C) 2013-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _MUL_SPLIT_H -#define _MUL_SPLIT_H - -#include <float.h> - -/* Calculate X * Y exactly and store the result in *HI + *LO. It is - given that the values are small enough that no overflow occurs and - large enough (or zero) that no underflow occurs. */ - -static void -mul_split (double *hi, double *lo, double x, double y) -{ -#ifdef __FP_FAST_FMA - /* Fast built-in fused multiply-add. */ - *hi = x * y; - *lo = __builtin_fma (x, y, -*hi); -#else - /* Apply Dekker's algorithm. */ - *hi = x * y; -# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1) - double x1 = x * C; - double y1 = y * C; -# undef C - x1 = (x - x1) + x1; - y1 = (y - y1) + y1; - double x2 = x - x1; - double y2 = y - y1; - *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2; -#endif -} - -#endif /* _MUL_SPLIT_H */ |