1 2 3 /* @(#)w_pow.c 5.2 93/10/01 */ 4 /* 5 * ==================================================== 6 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 7 * 8 * Developed at SunPro, a Sun Microsystems, Inc. business. 9 * Permission to use, copy, modify, and distribute this 10 * software is freely granted, provided that this notice 11 * is preserved. 12 * ==================================================== 13 */ 14 15 #include <sys/cdefs.h> 16 #if defined(LIBM_SCCS) && !defined(lint) 17 __RCSID("$NetBSD: w_pow.c,v 1.7 2002/05/26 22:02:02 wiz Exp $"); 18 #endif 19 20 /* 21 * wrapper pow(x,y) return x**y 22 */ 23 24 #include "math.h" 25 #include "math_private.h" 26 27 28 double 29 pow(double x, double y) /* wrapper pow */ 30 { 31 #ifdef _IEEE_LIBM 32 return __ieee754_pow(x,y); 33 #else 34 double z; 35 z=__ieee754_pow(x,y); 36 if(_LIB_VERSION == _IEEE_|| isnan(y)) return z; 37 if(isnan(x)) { 38 if(y==0.0) 39 return __kernel_standard(x,y,42); /* pow(NaN,0.0) */ 40 else 41 return z; 42 } 43 if(x==0.0){ 44 if(y==0.0) 45 return __kernel_standard(x,y,20); /* pow(0.0,0.0) */ 46 if(finite(y)&&y<0.0) 47 return __kernel_standard(x,y,23); /* pow(0.0,negative) */ 48 return z; 49 } 50 if(!finite(z)) { 51 if(finite(x)&&finite(y)) { 52 if(isnan(z)) 53 return __kernel_standard(x,y,24); /* pow neg**non-int */ 54 else 55 return __kernel_standard(x,y,21); /* pow overflow */ 56 } 57 } 58 if(z==0.0&&finite(x)&&finite(y)) 59 return __kernel_standard(x,y,22); /* pow underflow */ 60 return z; 61 #endif 62 } 63