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      1 /* w_expf.c -- float version of w_exp.c.
      2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian (at) cygnus.com.
      3  */
      4 
      5 /*
      6  * ====================================================
      7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      8  *
      9  * Developed at SunPro, a Sun Microsystems, Inc. business.
     10  * Permission to use, copy, modify, and distribute this
     11  * software is freely granted, provided that this notice
     12  * is preserved.
     13  * ====================================================
     14  */
     15 
     16 #include <sys/cdefs.h>
     17 #if defined(LIBM_SCCS) && !defined(lint)
     18 __RCSID("$NetBSD: w_expf.c,v 1.8 2025/08/24 21:37:31 nat Exp $");
     19 #endif
     20 
     21 /*
     22  * wrapper expf(x)
     23  */
     24 
     25 #include "namespace.h"
     26 #include "math.h"
     27 #include "math_private.h"
     28 
     29 #ifdef __weak_alias
     30 __weak_alias(expf, _expf)
     31 #endif
     32 
     33 #ifndef _IEEE_LIBM
     34 static const float
     35 o_threshold=  8.8721679688e+01,  /* 0x42b17180 */
     36 u_threshold= -1.0397208405e+02;  /* 0xc2cff1b5 */
     37 #endif
     38 
     39 float
     40 expf(float x)		/* wrapper expf */
     41 {
     42 #ifdef _IEEE_LIBM
     43 	return __ieee754_expf(x);
     44 #else
     45 	float z;
     46 	z = __ieee754_expf(x);
     47 	if(_LIB_VERSION == _IEEE_) return z;
     48 	if(finitef(x)) {
     49 	    if(x>o_threshold)
     50 	        /* exp overflow */
     51 	        return (float)__kernel_standard((double)x,(double)x,106);
     52 	    else if(x<u_threshold)
     53 	        /* exp underflow */
     54 	        return (float)__kernel_standard((double)x,(double)x,107);
     55 	}
     56 	return z;
     57 #endif
     58 }
     59