sf_isnanf.c

来自「Newlib 嵌入式 C库 标准实现代码」· C语言 代码 · 共 38 行

/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice 
 * is preserved.
 * ====================================================
 */

/*
 * __isnanf(x) returns 1 is x is nan, else 0;
 */

#include "fdlibm.h"

int
_DEFUN (__isnanf, (x),
	float x)
{
	__int32_t ix;
	GET_FLOAT_WORD(ix,x);
	ix &= 0x7fffffff;
	return FLT_UWORD_IS_NAN(ix);
}

#ifdef _DOUBLE_IS_32BITS

int
_DEFUN (__isnand, (x),
	double x)
{
	return __isnanf((float) x);
}

#endif /* defined(_DOUBLE_IS_32BITS) */