1 2 /* @(#)w_exp.c 1.4 04/04/22 */ 3 /* 4 * ==================================================== 5 * Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved. 6 * 7 * Permission to use, copy, modify, and distribute this 8 * software is freely granted, provided that this notice 9 * is preserved. 10 * ==================================================== 11 */ 12 13 /* 14 * wrapper ieee_exp(x) 15 */ 16 17 #include "fdlibm.h" 18 19 #ifdef __STDC__ 20 static const double 21 #else 22 static double 23 #endif 24 o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */ 25 u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */ 26 27 #ifdef __STDC__ 28 double ieee_exp(double x) /* wrapper exp */ 29 #else 30 double ieee_exp(x) /* wrapper exp */ 31 double x; 32 #endif 33 { 34 #ifdef _IEEE_LIBM 35 return __ieee754_exp(x); 36 #else 37 double z; 38 z = __ieee754_exp(x); 39 if(_LIB_VERSION == _IEEE_) return z; 40 if(ieee_finite(x)) { 41 if(x>o_threshold) 42 return __kernel_standard(x,x,6); /* exp overflow */ 43 else if(x<u_threshold) 44 return __kernel_standard(x,x,7); /* exp underflow */ 45 } 46 return z; 47 #endif 48 } 49
