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Diffstat (limited to 'sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c')
-rw-r--r--sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c90
1 files changed, 89 insertions, 1 deletions
diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c
index 1e06fcb16e..9e665b01ec 100644
--- a/sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c
+++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c
@@ -1 +1,89 @@
-/* The code is the same as llround. Use an alias, see s_llround.c. */
+/* Round double value to long int.
+ Copyright (C) 1997-2016 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 <fenv.h>
+#include <limits.h>
+#include <math.h>
+
+#include <math_private.h>
+
+/* For LP64, lround is an alias for llround. */
+#ifndef _LP64
+
+long int
+__lround (double x)
+{
+ int32_t j0;
+ int64_t i0;
+ long int result;
+ int sign;
+
+ EXTRACT_WORDS64 (i0, x);
+ j0 = ((i0 >> 52) & 0x7ff) - 0x3ff;
+ sign = i0 < 0 ? -1 : 1;
+ i0 &= UINT64_C(0xfffffffffffff);
+ i0 |= UINT64_C(0x10000000000000);
+
+ if (j0 < (int32_t) (8 * sizeof (long int)) - 1)
+ {
+ if (j0 < 0)
+ return j0 < -1 ? 0 : sign;
+ else if (j0 >= 52)
+ result = i0 << (j0 - 52);
+ else
+ {
+ i0 += UINT64_C(0x8000000000000) >> j0;
+
+ result = i0 >> (52 - j0);
+#ifdef FE_INVALID
+ if (sizeof (long int) == 4
+ && sign == 1
+ && result == LONG_MIN)
+ /* Rounding brought the value out of range. */
+ feraiseexcept (FE_INVALID);
+#endif
+ }
+ }
+ else
+ {
+ /* The number is too large. Unless it rounds to LONG_MIN,
+ FE_INVALID must be raised and the return value is
+ unspecified. */
+#ifdef FE_INVALID
+ if (sizeof (long int) == 4
+ && x <= (double) LONG_MIN - 0.5)
+ {
+ /* If truncation produces LONG_MIN, the cast will not raise
+ the exception, but may raise "inexact". */
+ feraiseexcept (FE_INVALID);
+ return LONG_MIN;
+ }
+#endif
+ return (long int) x;
+ }
+
+ return sign * result;
+}
+
+weak_alias (__lround, lround)
+# ifdef NO_LONG_DOUBLE
+strong_alias (__lround, __lroundl)
+weak_alias (__lround, lroundl)
+# endif
+
+#endif