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-rw-r--r--sysdeps/ieee754/ldbl-128/x2y2m1l.c76
1 files changed, 0 insertions, 76 deletions
diff --git a/sysdeps/ieee754/ldbl-128/x2y2m1l.c b/sysdeps/ieee754/ldbl-128/x2y2m1l.c
deleted file mode 100644
index d3f88331b5..0000000000
--- a/sysdeps/ieee754/ldbl-128/x2y2m1l.c
+++ /dev/null
@@ -1,76 +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_splitl.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 (_Float128 *hi, _Float128 *lo, _Float128 x, _Float128 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)
-{
- _Float128 pld = fabsl (*(const _Float128 *) p);
- _Float128 qld = fabsl (*(const _Float128 *) q);
- if (pld < qld)
- return -1;
- else if (pld == qld)
- 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. */
-
-_Float128
-__x2y2m1l (_Float128 x, _Float128 y)
-{
- _Float128 vals[5];
- SET_RESTORE_ROUNDL (FE_TONEAREST);
- mul_splitl (&vals[1], &vals[0], x, x);
- mul_splitl (&vals[3], &vals[2], y, y);
- vals[4] = -1;
- qsort (vals, 5, sizeof (_Float128), 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 <= 3; i++)
- {
- add_split (&vals[i + 1], &vals[i], vals[i + 1], vals[i]);
- qsort (vals + i + 1, 4 - i, sizeof (_Float128), compare);
- }
- /* Now any error from this addition will be small. */
- return vals[4] + vals[3] + vals[2] + vals[1] + vals[0];
-}