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-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_llroundl.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_llroundl.c b/sysdeps/ieee754/ldbl-128ibm/s_llroundl.c
new file mode 100644
index 0000000000..9e25024f96
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+++ b/sysdeps/ieee754/ldbl-128ibm/s_llroundl.c
@@ -0,0 +1,127 @@
+/* Round to long long int long double floating-point values.
+ IBM extended format long double version.
+ Copyright (C) 2006 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <math.h>
+#include <fenv_libc.h>
+#include <math_ldbl_opt.h>
+#include <float.h>
+#include <ieee754.h>
+
+#ifdef __STDC__
+long long
+__llroundl (long double x)
+#else
+long long
+__llroundl (x)
+ long double x;
+#endif
+{
+ double xh, xl;
+ long long res, hi, lo;
+
+ ldbl_unpack (x, &xh, &xl);
+
+ /* Limit the range of values handled by the conversion to long long.
+ We do this because we aren't sure whether that conversion properly
+ raises FE_INVALID. */
+ if (__builtin_expect
+ ((__builtin_fabs (xh) <= -(double) (-__LONG_LONG_MAX__ - 1)), 1)
+#if !defined (FE_INVALID)
+ || 1
+#endif
+ )
+ {
+ if (__builtin_expect ((xh == -(double) (-__LONG_LONG_MAX__ - 1)), 0))
+ {
+ /* When XH is 9223372036854775808.0, converting to long long will
+ overflow, resulting in an invalid operation. However, XL might
+ be negative and of sufficient magnitude that the overall long
+ double is in fact in range. Avoid raising an exception. In any
+ case we need to convert this value specially, because
+ the converted value is not exactly represented as a double
+ thus subtracting HI from XH suffers rounding error. */
+ hi = __LONG_LONG_MAX__;
+ xh = 1.0;
+ }
+ else
+ {
+ hi = (long long) xh;
+ xh -= hi;
+ }
+ ldbl_canonicalize (&xh, &xl);
+
+ lo = (long long) xh;
+
+ /* Peg at max/min values, assuming that the above conversions do so.
+ Strictly speaking, we can return anything for values that overflow,
+ but this is more useful. */
+ res = hi + lo;
+
+ /* This is just sign(hi) == sign(lo) && sign(res) != sign(hi). */
+ if (__builtin_expect (((~(hi ^ lo) & (res ^ hi)) < 0), 0))
+ goto overflow;
+
+ xh -= lo;
+ ldbl_canonicalize (&xh, &xl);
+
+ hi = res;
+ if (xh > 0.5)
+ {
+ res += 1;
+ }
+ else if (xh == 0.5)
+ {
+ if (xl > 0.0 || (xl == 0.0 && res >= 0))
+ res += 1;
+ }
+ else if (-xh > 0.5)
+ {
+ res -= 1;
+ }
+ else if (-xh == 0.5)
+ {
+ if (xl < 0.0 || (xl == 0.0 && res <= 0))
+ res -= 1;
+ }
+
+ if (__builtin_expect (((~(hi ^ (res - hi)) & (res ^ hi)) < 0), 0))
+ goto overflow;
+
+ return res;
+ }
+ else
+ {
+ if (xh > 0.0)
+ hi = __LONG_LONG_MAX__;
+ else if (xh < 0.0)
+ hi = -__LONG_LONG_MAX__ - 1;
+ else
+ /* Nan */
+ hi = 0;
+ }
+
+overflow:
+#ifdef FE_INVALID
+ feraiseexcept (FE_INVALID);
+#endif
+ return hi;
+}
+
+long_double_symbol (libm, __llroundl, llroundl);