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/* Copyright (C) 1998, 2000, 2006, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson.
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_ldbl_opt.h>
/* Use the -inf rounding mode conversion instructions to implement
ceil, via something akin to -floor(-x). This is much faster than
playing with the fpcr to achieve +inf rounding mode. */
double
__ceil (double x)
{
double two52 = copysign (0x1.0p52, x);
double r, tmp;
__asm (
#ifdef _IEEE_FP_INEXACT
"addt/suim %2, %3, %1\n\tsubt/suim %1, %3, %0"
#else
"addt/sum %2, %3, %1\n\tsubt/sum %1, %3, %0"
#endif
: "=&f"(r), "=&f"(tmp)
: "f"(-x), "f"(-two52));
/* Fix up the negation we did above, as well as handling -0 properly. */
return copysign (r, x);
}
weak_alias (__ceil, ceil)
#ifdef NO_LONG_DOUBLE
strong_alias (__ceil, __ceill)
weak_alias (__ceil, ceill)
#endif
#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
compat_symbol (libm, __ceil, ceill, GLIBC_2_0);
#endif
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