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-rw-r--r--sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c93
1 files changed, 0 insertions, 93 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c b/sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c
deleted file mode 100644
index 0bdb9a1848..0000000000
--- a/sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/* Compute x^2 + y^2 - 1, without large cancellation error.
- Copyright (C) 2012-2017 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/>. */
-
-#include <math.h>
-#include <math_private.h>
-#include <mul_split.h>
-#include <stdlib.h>
-
-/* Calculate X + Y exactly and store the result in *HI + *LO. It is
- given that |X| >= |Y| and the values are small enough that no
- overflow occurs. */
-
-static inline void
-add_split (double *hi, double *lo, double x, double y)
-{
- /* Apply Dekker's algorithm. */
- *hi = x + y;
- *lo = (x - *hi) + y;
-}
-
-/* Compare absolute values of floating-point values pointed to by P
- and Q for qsort. */
-
-static int
-compare (const void *p, const void *q)
-{
- double pd = fabs (*(const double *) p);
- double qd = fabs (*(const double *) q);
- if (pd < qd)
- return -1;
- else if (pd == qd)
- return 0;
- else
- return 1;
-}
-
-/* Return X^2 + Y^2 - 1, computed without large cancellation error.
- It is given that 1 > X >= Y >= epsilon / 2, and that X^2 + Y^2 >=
- 0.5. */
-
-long double
-__x2y2m1l (long double x, long double y)
-{
- double vals[13];
- SET_RESTORE_ROUND (FE_TONEAREST);
- union ibm_extended_long_double xu, yu;
- xu.ld = x;
- yu.ld = y;
- if (fabs (xu.d[1].d) < 0x1p-500)
- xu.d[1].d = 0.0;
- if (fabs (yu.d[1].d) < 0x1p-500)
- yu.d[1].d = 0.0;
- mul_split (&vals[1], &vals[0], xu.d[0].d, xu.d[0].d);
- mul_split (&vals[3], &vals[2], xu.d[0].d, xu.d[1].d);
- vals[2] *= 2.0;
- vals[3] *= 2.0;
- mul_split (&vals[5], &vals[4], xu.d[1].d, xu.d[1].d);
- mul_split (&vals[7], &vals[6], yu.d[0].d, yu.d[0].d);
- mul_split (&vals[9], &vals[8], yu.d[0].d, yu.d[1].d);
- vals[8] *= 2.0;
- vals[9] *= 2.0;
- mul_split (&vals[11], &vals[10], yu.d[1].d, yu.d[1].d);
- vals[12] = -1.0;
- qsort (vals, 13, sizeof (double), compare);
- /* Add up the values so that each element of VALS has absolute value
- at most equal to the last set bit of the next nonzero
- element. */
- for (size_t i = 0; i <= 11; i++)
- {
- add_split (&vals[i + 1], &vals[i], vals[i + 1], vals[i]);
- qsort (vals + i + 1, 12 - i, sizeof (double), compare);
- }
- /* Now any error from this addition will be small. */
- long double retval = (long double) vals[12];
- for (size_t i = 11; i != (size_t) -1; i--)
- retval += (long double) vals[i];
- return retval;
-}