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-rw-r--r--libquadmath/math/remquoq.c107
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diff --git a/libquadmath/math/remquoq.c b/libquadmath/math/remquoq.c
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+/* Compute remainder and a congruent to the quotient.
+ Copyright (C) 1997, 1999, 2002 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 "quadmath-imp.h"
+
+
+static const __float128 zero = 0.0;
+
+
+__float128
+remquoq (__float128 x, __float128 y, int *quo)
+{
+ int64_t hx,hy;
+ uint64_t sx,lx,ly,qs;
+ int cquo;
+
+ GET_FLT128_WORDS64 (hx, lx, x);
+ GET_FLT128_WORDS64 (hy, ly, y);
+ sx = hx & 0x8000000000000000ULL;
+ qs = sx ^ (hy & 0x8000000000000000ULL);
+ hy &= 0x7fffffffffffffffLL;
+ hx &= 0x7fffffffffffffffLL;
+
+ /* Purge off exception values. */
+ if ((hy | ly) == 0)
+ return (x * y) / (x * y); /* y = 0 */
+ if ((hx >= 0x7fff000000000000LL) /* x not finite */
+ || ((hy >= 0x7fff000000000000LL) /* y is NaN */
+ && (((hy - 0x7fff000000000000LL) | ly) != 0)))
+ return (x * y) / (x * y);
+
+ if (hy <= 0x7ffbffffffffffffLL)
+ x = fmodq (x, 8 * y); /* now x < 8y */
+
+ if (((hx - hy) | (lx - ly)) == 0)
+ {
+ *quo = qs ? -1 : 1;
+ return zero * x;
+ }
+
+ x = fabsq (x);
+ y = fabsq (y);
+ cquo = 0;
+
+ if (x >= 4 * y)
+ {
+ x -= 4 * y;
+ cquo += 4;
+ }
+ if (x >= 2 * y)
+ {
+ x -= 2 * y;
+ cquo += 2;
+ }
+
+ if (hy < 0x0002000000000000LL)
+ {
+ if (x + x > y)
+ {
+ x -= y;
+ ++cquo;
+ if (x + x >= y)
+ {
+ x -= y;
+ ++cquo;
+ }
+ }
+ }
+ else
+ {
+ __float128 y_half = 0.5Q * 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;
+}