| s_tan.c (117912) | s_tan.c (151969) |
|---|---|
| 1/* @(#)s_tan.c 5.1 93/09/24 */ 2/* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunPro, a Sun Microsystems, Inc. business. 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#ifndef lint | 1/* @(#)s_tan.c 5.1 93/09/24 */ 2/* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunPro, a Sun Microsystems, Inc. business. 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#ifndef lint |
| 14static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_tan.c 117912 2003-07-23 04:53:47Z peter $"; | 14static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_tan.c 151969 2005-11-02 14:01:45Z bde $"; |
| 15#endif 16 17/* tan(x) 18 * Return tangent function of x. 19 * 20 * kernel function: 21 * __kernel_tan ... tangent function on [-pi/4,pi/4] 22 * __ieee754_rem_pio2 ... argument reduction routine --- 30 unchanged lines hidden (view full) --- 53 double y[2],z=0.0; 54 int32_t n, ix; 55 56 /* High word of x. */ 57 GET_HIGH_WORD(ix,x); 58 59 /* |x| ~< pi/4 */ 60 ix &= 0x7fffffff; | 15#endif 16 17/* tan(x) 18 * Return tangent function of x. 19 * 20 * kernel function: 21 * __kernel_tan ... tangent function on [-pi/4,pi/4] 22 * __ieee754_rem_pio2 ... argument reduction routine --- 30 unchanged lines hidden (view full) --- 53 double y[2],z=0.0; 54 int32_t n, ix; 55 56 /* High word of x. */ 57 GET_HIGH_WORD(ix,x); 58 59 /* |x| ~< pi/4 */ 60 ix &= 0x7fffffff; |
| 61 if(ix <= 0x3fe921fb) return __kernel_tan(x,z,1); | 61 if(ix <= 0x3fe921fb) { 62 if(ix<0x3e300000) /* x < 2**-28 */ 63 if((int)x==0) return x; /* generate inexact */ 64 return __kernel_tan(x,z,1); 65 } |
| 62 63 /* tan(Inf or NaN) is NaN */ 64 else if (ix>=0x7ff00000) return x-x; /* NaN */ 65 66 /* argument reduction needed */ 67 else { 68 n = __ieee754_rem_pio2(x,y); 69 return __kernel_tan(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even 70 -1 -- n odd */ 71 } 72} | 66 67 /* tan(Inf or NaN) is NaN */ 68 else if (ix>=0x7ff00000) return x-x; /* NaN */ 69 70 /* argument reduction needed */ 71 else { 72 n = __ieee754_rem_pio2(x,y); 73 return __kernel_tan(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even 74 -1 -- n odd */ 75 } 76} |