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-rw-r--r--sysdeps/ieee754/dbl-64/x2y2m1.c34
1 files changed, 2 insertions, 32 deletions
diff --git a/sysdeps/ieee754/dbl-64/x2y2m1.c b/sysdeps/ieee754/dbl-64/x2y2m1.c
index 96078888a7..aa0d9703fa 100644
--- a/sysdeps/ieee754/dbl-64/x2y2m1.c
+++ b/sysdeps/ieee754/dbl-64/x2y2m1.c
@@ -1,5 +1,5 @@
/* Compute x^2 + y^2 - 1, without large cancellation error.
- Copyright (C) 2012-2016 Free Software Foundation, Inc.
+ Copyright (C) 2012-2018 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
@@ -18,7 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
+#include <mul_split.h>
#include <stdlib.h>
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
@@ -33,36 +33,6 @@ add_split (double *hi, double *lo, double x, double y)
*lo = (x - *hi) + y;
}
-/* 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
-}
-
/* Compare absolute values of floating-point values pointed to by P
and Q for qsort. */