root/usr/src/lib/libm/common/LD/__sincosl.c
/*
 * 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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/* INDENT OFF */
/*
 * long double __k_sincos( long double x, long double y, long double *c )
 * kernel sincosl function on [-pi/4, pi/4], pi/4 ~ 0.785398164
 * Input x is assumed to be bounded by ~pi/4 in magnitude.
 * Input y is the tail of x.
 * return sinl(x) with *c = cosl(x)
 *
 * Table look up algorithm
 *      see __k_sinl() and __k_cosl()
 */

#include "libm.h"

#include <sys/isa_defs.h>

extern const long double _TBL_sinl_hi[], _TBL_sinl_lo[], _TBL_cosl_hi[],
        _TBL_cosl_lo[];
static const long double
one     = 1.0,
/*
 * |sin(x) - (x+pp1*x^3+...+pp5*x^11)| <= 2^-122.32 for |x|<1/64
 */
pp1     = -1.666666666666666666666666666586782940810e-0001L,
pp2     =  8.333333333333333333333003723660929317540e-0003L,
pp3     = -1.984126984126984076045903483778337804470e-0004L,
pp4     =  2.755731922361906641319723106210900949413e-0006L,
pp5     = -2.505198398570947019093998469135012057673e-0008L,
/*
 * |(sin(x) - (x+p1*x^3+...+p8*x^17)|
 * |------------------------------- | <= 2^-116.17 for |x|<0.1953125
 * |                 x              |
 */
p1      =  -1.666666666666666666666666666666211262297e-0001L,
p2      =   8.333333333333333333333333301497876908541e-0003L,
p3      =  -1.984126984126984126984041302881180621922e-0004L,
p4      =   2.755731922398589064100587351307269621093e-0006L,
p5      =  -2.505210838544163129378906953765595393873e-0008L,
p6      =   1.605904383643244375050998243778534074273e-0010L,
p7      =  -7.647162722800685516901456114270824622699e-0013L,
p8      =   2.810046428661902961725428841068844462603e-0015L,
/*
 *
 * |cos(x) - (1+qq1*x^2+...+ qq5*x^10)| <= 2^-123.84 for |x|<=1/128
 */
qq1     =  -4.999999999999999999999999999999378373641e-0001L,
qq2     =   4.166666666666666666666665478399327703130e-0002L,
qq3     =  -1.388888888888888888058211230618051613494e-0003L,
qq4     =   2.480158730156105377771585658905303111866e-0005L,
qq5     =  -2.755728099762526325736488376695157008736e-0007L,
/*
 *
 * |cos(x) - (1+q1*x^2+...+ q8*x^16)| <= 2^-117.11 for |x|<= 0.15625
 */
q1      =  -4.999999999999999999999999999999756416975e-0001L,
q2      =   4.166666666666666666666666664006066577258e-0002L,
q3      =  -1.388888888888888888888877700363937169637e-0003L,
q4      =   2.480158730158730158494468463031814083559e-0005L,
q5      =  -2.755731922398586276322819250356005542871e-0007L,
q6      =   2.087675698767424261441959760729854017855e-0009L,
q7      =  -1.147074481239662089072452129010790774761e-0011L,
q8      =   4.777761647399651599730663422263531034782e-0014L;
/* INDENT ON */
long double
__k_sincosl(long double x, long double y, long double *c) {
        long double a1, a2, t, t1, t2, z, w;
        int *pt = (int *) &t, *px = (int *) &x;
        int i, j, hx, ix;

        t = 1.0;
#if defined(__i386) || defined(__amd64)
        XTOI(px, hx);
#else
        hx = px[0];
#endif
        ix = hx & 0x7fffffff;
        if (ix < 0x3ffc4000) {
                if (ix < 0x3fc60000)
                        if (((int) x) == 0) {
                                *c = one;
                                return (x);
                        }       /* generate inexact */
                z = x * x;

                if (ix < 0x3ff80000) {
                        *c = one + z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 +
                                z * qq5))));
                        t = z * (p1 + z * (p2 + z * (p3 + z * (p4 + z * (p5 +
                                z * p6)))));
                } else {
                        *c = one + z * (q1 + z * (q2 + z * (q3 + z * (q4 + z *
                                (q5 + z * (q6 + z * (q7 + z * q8)))))));
                        t = z * (p1 + z * (p2 + z * (p3 + z * (p4 + z * (p5 +
                                z * (p6 + z * (p7 + z * p8)))))));
                }

                t = y + x * t;
                return (x + t);
        }
        j = (ix + 0x400) & 0x7ffff800;
        i = (j - 0x3ffc4000) >> 11;
#if defined(__i386) || defined(__amd64)
        ITOX(j, pt);
#else
        pt[0] = j;
#endif
        if (hx > 0)
                x = y - (t - x);
        else
                x = (-y) - (t + x);
        a1 = _TBL_sinl_hi[i];
        z = x * x;
        t = z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 + z * qq5))));
        w = x * (one + z * (pp1 + z * (pp2 + z * (pp3 + z * (pp4 + z *
                pp5)))));
        a2 = _TBL_cosl_hi[i];
        t2 = _TBL_cosl_lo[i] - (a1 * w - a2 * t);
        *c = a2 + t2;
        t1 = a2 * w + a1 * t;
        t1 += _TBL_sinl_lo[i];
        if (hx < 0)
                return (-a1 - t1);
        else
                return (a1 + t1);
}