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authorJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
commit0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (patch)
tree2ea1f8305970753e4a657acb2ccc15ca3eec8e2c /sysdeps/ieee754/ldbl-128ibm/s_remquol.c
parent7d58530341304d403a6626d7f7a1913165fe2f32 (diff)
downloadglibc-0ecb606cb6cf65de1d9fc8a919bceb4be476c602.tar.gz
2.5-18.1
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_remquol.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_remquol.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_remquol.c b/sysdeps/ieee754/ldbl-128ibm/s_remquol.c
new file mode 100644
index 0000000000..ca504a01a0
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_remquol.c
@@ -0,0 +1,111 @@
+/* Compute remainder and a congruent to the quotient.
+ Copyright (C) 1997,1999,2002,2004,2006 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
+ Jakub Jelinek <jj@ultra.linux.cz>, 1999.
+
+ 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <math.h>
+
+#include "math_private.h"
+#include <math_ldbl_opt.h>
+
+
+static const long double zero = 0.0;
+
+
+long double
+__remquol (long double x, long double y, int *quo)
+{
+ int64_t hx,hy;
+ u_int64_t sx,lx,ly,qs;
+ int cquo;
+
+ GET_LDOUBLE_WORDS64 (hx, lx, x);
+ GET_LDOUBLE_WORDS64 (hy, ly, y);
+ sx = hx & 0x8000000000000000ULL;
+ qs = sx ^ (hy & 0x8000000000000000ULL);
+ hy &= 0x7fffffffffffffffLL;
+ hx &= 0x7fffffffffffffffLL;
+
+ /* Purge off exception values. */
+ if ((hy | (ly & 0x7fffffffffffffff)) == 0)
+ return (x * y) / (x * y); /* y = 0 */
+ if ((hx >= 0x7ff0000000000000LL) /* x not finite */
+ || ((hy >= 0x7ff0000000000000LL) /* y is NaN */
+ && (((hy - 0x7ff0000000000000LL) | ly) != 0)))
+ return (x * y) / (x * y);
+
+ if (hy <= 0x7fbfffffffffffffLL)
+ x = __ieee754_fmodl (x, 8 * y); /* now x < 8y */
+
+ if (((hx - hy) | (lx - ly)) == 0)
+ {
+ *quo = qs ? -1 : 1;
+ return zero * x;
+ }
+
+ x = fabsl (x);
+ y = fabsl (y);
+ cquo = 0;
+
+ if (x >= 4 * y)
+ {
+ x -= 4 * y;
+ cquo += 4;
+ }
+ if (x >= 2 * y)
+ {
+ x -= 2 * y;
+ cquo += 2;
+ }
+
+ if (hy < 0x0020000000000000LL)
+ {
+ if (x + x > y)
+ {
+ x -= y;
+ ++cquo;
+ if (x + x >= y)
+ {
+ x -= y;
+ ++cquo;
+ }
+ }
+ }
+ else
+ {
+ long double y_half = 0.5L * y;
+ if (x > y_half)
+ {
+ x -= y;
+ ++cquo;
+ if (x >= y_half)
+ {
+ x -= y;
+ ++cquo;
+ }
+ }
+ }
+
+ *quo = qs ? -cquo : cquo;
+
+ if (sx)
+ x = -x;
+ return x;
+}
+long_double_symbol (libm, __remquol, remquol);