diff options
Diffstat (limited to 'usr/src/lib/libm/common/R/tanf.c')
| -rw-r--r-- | usr/src/lib/libm/common/R/tanf.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/R/tanf.c b/usr/src/lib/libm/common/R/tanf.c new file mode 100644 index 0000000000..cc57c66bbb --- /dev/null +++ b/usr/src/lib/libm/common/R/tanf.c @@ -0,0 +1,159 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2011 Nexenta Systems, Inc. All rights reserved. + */ +/* + * Copyright 2005 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma weak tanf = __tanf + +#include "libm.h" + +extern const int _TBL_ipio2_inf[]; +extern int __rem_pio2m(double *, double *, int, int, int, const int *); +#if defined(__i386) && !defined(__amd64) +extern int __swapRP(int); +#endif + +static const double C[] = { + 1.0, + 4.46066928428959230679140546271810308098793029785e-0003, + 4.92165316309189027066395283327437937259674072266e+0000, + -7.11410648161473480044492134766187518835067749023e-0001, + 4.08549808374053391446523164631798863410949707031e+0000, + 2.50411070398050927821032018982805311679840087891e+0000, + 1.11492064560251158411574579076841473579406738281e+0001, + -1.50565540968422650891511693771462887525558471680e+0000, + -1.81484378878349295050043110677506774663925170898e+0000, + 3.333335997532835641297409611782510896641e-0001, + 2.999997598248363761541668282006867229939e+00, + 0.636619772367581343075535, /* 2^ -1 * 1.45F306DC9C883 */ + 0.5, + 1.570796326734125614166, /* 2^ 0 * 1.921FB54400000 */ + 6.077100506506192601475e-11, /* 2^-34 * 1.0B4611A626331 */ +}; + +#define one C[0] +#define P0 C[1] +#define P1 C[2] +#define P2 C[3] +#define P3 C[4] +#define P4 C[5] +#define P5 C[6] +#define P6 C[7] +#define P7 C[8] +#define T0 C[9] +#define T1 C[10] +#define invpio2 C[11] +#define half C[12] +#define pio2_1 C[13] +#define pio2_t C[14] + +float +tanf(float x) +{ + double y, z, w; + float f; + int n, ix, hx, hy; + volatile int i; + + hx = *((int *)&x); + ix = hx & 0x7fffffff; + + y = (double)x; + + if (ix <= 0x4016cbe4) { /* |x| < 3*pi/4 */ + if (ix <= 0x3f490fdb) { /* |x| < pi/4 */ + if (ix < 0x3c000000) { /* |x| < 2**-7 */ + if (ix <= 0x39800000) { /* |x| < 2**-12 */ + i = (int)y; +#ifdef lint + i = i; +#endif + return (x); + } + return ((float)((y * T0) * (T1 + y * y))); + } + z = y * y; + return ((float)(((P0 * y) * (P1 + z * (P2 + z)) * + (P3 + z * (P4 + z))) * + (P5 + z * (P6 + z * (P7 + z))))); + } + if (hx > 0) + y = (y - pio2_1) - pio2_t; + else + y = (y + pio2_1) + pio2_t; + hy = ((int *)&y)[HIWORD] & ~0x80000000; + if (hy < 0x3f800000) { /* |y| < 2**-7 */ + z = (y * T0) * (T1 + y * y); + return ((float)(-one / z)); + } + z = y * y; + w = ((P0 * y) * (P1 + z * (P2 + z)) * (P3 + z * (P4 + z))) * + (P5 + z * (P6 + z * (P7 + z))); + return ((float)(-one / w)); + } + + if (ix <= 0x49c90fdb) { /* |x| < 2^19*pi */ +#if defined(__i386) && !defined(__amd64) + int rp; + + rp = __swapRP(fp_extended); +#endif + w = y * invpio2; + if (hx < 0) + n = (int)(w - half); + else + n = (int)(w + half); + y = (y - n * pio2_1) - n * pio2_t; +#if defined(__i386) && !defined(__amd64) + if (rp != fp_extended) + (void) __swapRP(rp); +#endif + } else { + if (ix >= 0x7f800000) + return (x / x); /* sin(Inf or NaN) is NaN */ + hy = ((int *)&y)[HIWORD]; + n = ((hy >> 20) & 0x7ff) - 1046; + ((int *)&w)[HIWORD] = (hy & 0xfffff) | 0x41600000; + ((int *)&w)[LOWORD] = ((int *)&y)[LOWORD]; + n = __rem_pio2m(&w, &y, n, 1, 0, _TBL_ipio2_inf); + if (hy < 0) { + y = -y; + n = -n; + } + } + + hy = ((int *)&y)[HIWORD] & ~0x80000000; + if (hy < 0x3f800000) { /* |y| < 2**-7 */ + z = (y * T0) * (T1 + y * y); + f = ((n & 1) == 0)? (float)z : (float)(-one / z); + return (f); + } + z = y * y; + w = ((P0 * y) * (P1 + z * (P2 + z)) * (P3 + z * (P4 + z))) * + (P5 + z * (P6 + z * (P7 + z))); + f = ((n & 1) == 0)? (float)w : (float)(-one / w); + return (f); +} |