glibc/sysdeps/alpha/fpu/s_ceilf.c

60 lines
2.1 KiB
C

/* Copyright (C) 1998 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <math.h>
float
__ceilf (float x)
{
if (x != 0 && fabsf (x) < 16777216.0f) /* 1 << FLT_MANT_DIG */
{
float tmp1, tmp2;
unsigned long fpcr0, fpcr1;
unsigned long pinf = 3UL << 58;
/* Set round to +inf. */
__asm __volatile("excb; mf_fpcr %0" : "=f"(fpcr0));
__asm __volatile("mt_fpcr %0; excb" : : "f"(fpcr0 | pinf));
/* Calculate!
Note that Alpha S_Floating is stored in registers in a
restricted T_Floating format, so we don't even need to
convert back to S_Floating in the end. The initial
conversion to T_Floating is needed to handle denormals. */
#ifdef _IEEE_FP_INEXACT
__asm("cvtst/s %3,%2\n\tcvttq/svid %2,%1\n\tcvtqt/suid %1,%0"
: "=f"(x), "=&f"(tmp1), "=&f"(tmp2)
: "f"(x));
#else
__asm("cvtst/s %3,%2\n\tcvttq/svd %2,%1\n\tcvtqt/d %1,%0"
: "=f"(x), "=&f"(tmp1), "=&f"(tmp2)
: "f"(x));
#endif
/* Reset rounding mode, while retaining new exception bits. */
__asm __volatile("excb; mf_fpcr %0" : "=f"(fpcr1));
fpcr0 = (fpcr0 & pinf) | (fpcr1 & ~pinf);
__asm __volatile("mt_fpcr %0; excb" : : "f"(fpcr0));
}
return x;
}
weak_alias (__ceilf, ceilf)