diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/lgamma_product.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/lgamma_product.c | 34 |
1 files changed, 2 insertions, 32 deletions
diff --git a/sysdeps/ieee754/dbl-64/lgamma_product.c b/sysdeps/ieee754/dbl-64/lgamma_product.c index d956575bc7..b37ecee73f 100644 --- a/sysdeps/ieee754/dbl-64/lgamma_product.c +++ b/sysdeps/ieee754/dbl-64/lgamma_product.c @@ -1,5 +1,5 @@ /* Compute a product of 1 + (T/X), 1 + (T/(X+1)), .... - Copyright (C) 2015-2016 Free Software Foundation, Inc. + Copyright (C) 2015-2018 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 @@ -18,37 +18,7 @@ #include <math.h> #include <math_private.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); -#elif defined FP_FAST_FMA - /* Fast library fused multiply-add, compiler before GCC 4.6. */ - *hi = x * y; - *lo = __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 -} +#include <mul_split.h> /* Compute the product of 1 + (T / (X + X_EPS)), 1 + (T / (X + X_EPS + 1)), ..., 1 + (T / (X + X_EPS + N - 1)), minus 1. X is such that |