| /* s_tanf.c -- float version of s_tan.c. |
| * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
| */ |
| |
| /* |
| * ==================================================== |
| * 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. |
| * ==================================================== |
| */ |
| |
| #if defined(LIBM_SCCS) && !defined(lint) |
| static char rcsid[] = "$NetBSD: s_tanf.c,v 1.4 1995/05/10 20:48:20 jtc Exp $"; |
| #endif |
| |
| #include <errno.h> |
| #include <math.h> |
| #include <math_private.h> |
| #include <libm-alias-float.h> |
| |
| float __tanf(float x) |
| { |
| float y[2],z=0.0; |
| int32_t n, ix; |
| |
| GET_FLOAT_WORD(ix,x); |
| |
| /* |x| ~< pi/4 */ |
| ix &= 0x7fffffff; |
| if(ix <= 0x3f490fda) return __kernel_tanf(x,z,1); |
| |
| /* tan(Inf or NaN) is NaN */ |
| else if (ix>=0x7f800000) { |
| if (ix==0x7f800000) |
| __set_errno (EDOM); |
| return x-x; /* NaN */ |
| } |
| |
| /* argument reduction needed */ |
| else { |
| n = __ieee754_rem_pio2f(x,y); |
| return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even |
| -1 -- n odd */ |
| } |
| } |
| libm_alias_float (__tan, tan) |