1 /* w_powf.c -- float version of w_pow.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@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_powf.c,v 1.4 1997/10/09 11:35:51 lukem Exp $"); 19 #endif 20 21 /* 22 * wrapper powf(x,y) return x**y 23 */ 24 25 #include "math.h" 26 #include "math_private.h" 27 28 29 #ifdef __STDC__ 30 float powf(float x, float y) /* wrapper powf */ 31 #else 32 float powf(x,y) /* wrapper powf */ 33 float x,y; 34 #endif 35 { 36 #ifdef _IEEE_LIBM 37 return __ieee754_powf(x,y); 38 #else 39 float z; 40 z=__ieee754_powf(x,y); 41 if(_LIB_VERSION == _IEEE_|| isnanf(y)) return z; 42 if(isnanf(x)) { 43 if(y==(float)0.0) 44 /* powf(NaN,0.0) */ 45 return (float)__kernel_standard((double)x,(double)y,142); 46 else 47 return z; 48 } 49 if(x==(float)0.0){ 50 if(y==(float)0.0) 51 /* powf(0.0,0.0) */ 52 return (float)__kernel_standard((double)x,(double)y,120); 53 if(finitef(y)&&y<(float)0.0) 54 /* powf(0.0,negative) */ 55 return (float)__kernel_standard((double)x,(double)y,123); 56 return z; 57 } 58 if(!finitef(z)) { 59 if(finitef(x)&&finitef(y)) { 60 if(isnanf(z)) 61 /* powf neg**non-int */ 62 return (float)__kernel_standard((double)x,(double)y,124); 63 else 64 /* powf overflow */ 65 return (float)__kernel_standard((double)x,(double)y,121); 66 } 67 } 68 if(z==(float)0.0&&finitef(x)&&finitef(y)) 69 /* powf underflow */ 70 return (float)__kernel_standard((double)x,(double)y,122); 71 return z; 72 #endif 73 } 74