glibc/sysdeps/powerpc/powerpc32/fpu/s_isnan.S

/* isnan().  PowerPC32 version.
   Copyright (C) 2008-2017 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 <sysdep.h>
#include <math_ldbl_opt.h>

/* int __isnan(x)  */
	.machine power4
EALIGN (__isnan, 4, 0)
	mffs	fp0
	mtfsb0	4*cr6+lt /* reset_fpscr_bit (FPSCR_VE) */
	fcmpu	cr7,fp1,fp1
	mtfsf	255,fp0
	li	r3,0
	beqlr+	cr7	/* (x == x) then not a NAN */
	li	r3,1	/* else must be a NAN */
	blr
	END (__isnan)

hidden_def (__isnan)
weak_alias (__isnan, isnan)

/* It turns out that the 'double' version will also always work for
   single-precision.  */
#ifndef __isnan
strong_alias (__isnan, __isnanf)
hidden_def (__isnanf)
weak_alias (__isnanf, isnanf)
#endif

#ifdef NO_LONG_DOUBLE
strong_alias (__isnan, __isnanl)
weak_alias (__isnan, isnanl)
#endif

#if !IS_IN (libm)
# if LONG_DOUBLE_COMPAT(libc, GLIBC_2_0)
compat_symbol (libc, __isnan, __isnanl, GLIBC_2_0);
compat_symbol (libc, isnan, isnanl, GLIBC_2_0);
# endif
#endif