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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_nextupl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_nextupl.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_nextupl.c b/sysdeps/ieee754/ldbl-128ibm/s_nextupl.c
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index 0000000000..9b532a3a25
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_nextupl.c
@@ -0,0 +1,79 @@
+/* Return the least floating-point number greater than X.
+ Copyright (C) 2016-2018 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
+ 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 <float.h>
+#include <math.h>
+#include <math_private.h>
+#include <math_ldbl_opt.h>
+
+/* Return the least floating-point number greater than X. */
+long double
+__nextupl (long double x)
+{
+ int64_t hx, ihx, lx;
+ double xhi, xlo, yhi;
+
+ ldbl_unpack (x, &xhi, &xlo);
+ EXTRACT_WORDS64 (hx, xhi);
+ EXTRACT_WORDS64 (lx, xlo);
+ ihx = hx & 0x7fffffffffffffffLL;
+
+ if (ihx > 0x7ff0000000000000LL) /* x is nan. */
+ return x + x; /* Signal the nan. */
+ if (ihx == 0)
+ return LDBL_TRUE_MIN;
+
+ long double u;
+ if ((hx == 0x7fefffffffffffffLL) && (lx == 0x7c8ffffffffffffeLL))
+ return INFINITY;
+ if ((uint64_t) hx >= 0xfff0000000000000ULL)
+ {
+ u = -0x1.fffffffffffff7ffffffffffff8p+1023L;
+ return u;
+ }
+ if (ihx <= 0x0360000000000000LL)
+ { /* x <= LDBL_MIN. */
+ x += LDBL_TRUE_MIN;
+ if (x == 0.0L) /* Handle negative LDBL_TRUE_MIN case. */
+ x = -0.0L;
+ return x;
+ }
+ /* If the high double is an exact power of two and the low
+ double is the opposite sign, then 1ulp is one less than
+ what we might determine from the high double. Similarly
+ if X is an exact power of two, and negative, because
+ making it a little larger will result in the exponent
+ decreasing by one and normalisation of the mantissa. */
+ if ((hx & 0x000fffffffffffffLL) == 0
+ && ((lx != 0 && lx != 0x8000000000000000LL && (hx ^ lx) < 0)
+ || ((lx == 0 || lx == 0x8000000000000000LL) && hx < 0)))
+ ihx -= 1LL << 52;
+ if (ihx < (106LL << 52))
+ { /* ulp will denormal. */
+ INSERT_WORDS64 (yhi, ihx & (0x7ffLL << 52));
+ u = yhi * 0x1p-105;
+ }
+ else
+ {
+ INSERT_WORDS64 (yhi, (ihx & (0x7ffLL << 52)) - (105LL << 52));
+ u = yhi;
+ }
+ return x + u;
+}
+
+weak_alias (__nextupl, nextupl)