/*
 * 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.
 */

/*
 * __vsinf: single precision vector sin
 *
 * Algorithm:
 *
 * For |x| < pi/4, approximate sin(x) by a polynomial x+x*z*(S0+
 * z*(S1+z*S2)) and cos(x) by a polynomial 1+z*(-1/2+z*(C0+z*(C1+
 * z*C2))), where z = x*x, all evaluated in double precision.
 *
 * Accuracy:
 *
 * The largest error is less than 0.6 ulps.
 */

#include <sys/isa_defs.h>

#ifdef _LITTLE_ENDIAN
#define HI(x)   *(1+(int *)&x)
#define LO(x)   *(unsigned *)&x
#else
#define HI(x)   *(int *)&x
#define LO(x)   *(1+(unsigned *)&x)
#endif

#ifdef __RESTRICT
#define restrict _Restrict
#else
#define restrict
#endif

extern int __vlibm_rem_pio2m(double *, double *, int, int, int);

static const double C[] = {
        -1.66666552424430847168e-01,    /* 2^ -3 * -1.5555460000000 */
        8.33219196647405624390e-03,     /* 2^ -7 *  1.11077E0000000 */
        -1.95187909412197768688e-04,    /* 2^-13 * -1.9956B60000000 */
        1.0,
        -0.5,
        4.16666455566883087158e-02,     /* 2^ -5 *  1.55554A0000000 */
        -1.38873036485165357590e-03,    /* 2^-10 * -1.6C0C1E0000000 */
        2.44309903791872784495e-05,     /* 2^-16 *  1.99E24E0000000 */
        0.636619772367581343075535,     /* 2^ -1  * 1.45F306DC9C883 */
        6755399441055744.0,             /* 2^ 52  * 1.8000000000000 */
        1.570796326734125614166,        /* 2^  0  * 1.921FB54400000 */
        6.077100506506192601475e-11,    /* 2^-34  * 1.0B4611A626331 */
};

#define S0      C[0]
#define S1      C[1]
#define S2      C[2]
#define one     C[3]
#define mhalf   C[4]
#define C0      C[5]
#define C1      C[6]
#define C2      C[7]
#define invpio2 C[8]
#define c3two51 C[9]
#define pio2_1  C[10]
#define pio2_t  C[11]

#define PREPROCESS(N, index, label)                                     \
        hx = *(int *)x;                                                 \
        ix = hx & 0x7fffffff;                                           \
        t = *x;                                                         \
        x += stridex;                                                   \
        if (ix <= 0x3f490fdb) { /* |x| < pi/4 */                        \
                if (ix == 0) {                                          \
                        y[index] = t;                                   \
                        goto label;                                     \
                }                                                       \
                y##N = (double)t;                                       \
                n##N = 0;                                               \
        } else if (ix <= 0x49c90fdb) { /* |x| < 2^19*pi */              \
                y##N = (double)t;                                       \
                medium = 1;                                             \
        } else {                                                        \
                if (ix >= 0x7f800000) { /* inf or nan */                \
                        y[index] = t / t;                               \
                        goto label;                                     \
                }                                                       \
                z##N = y##N = (double)t;                                \
                hx = HI(y##N);                                          \
                n##N = ((hx >> 20) & 0x7ff) - 1046;                     \
                HI(z##N) = (hx & 0xfffff) | 0x41600000;                 \
                n##N = __vlibm_rem_pio2m(&z##N, &y##N, n##N, 1, 0);     \
                if (hx < 0) {                                           \
                        y##N = -y##N;                                   \
                        n##N = -n##N;                                   \
                }                                                       \
                z##N = y##N * y##N;                                     \
                if (n##N & 1) { /* compute cos y */                     \
                        f##N = (float)(one + z##N * (mhalf + z##N *     \
                            (C0 + z##N * (C1 + z##N * C2))));           \
                } else { /* compute sin y */                            \
                        f##N = (float)(y##N + y##N * z##N * (S0 +       \
                            z##N * (S1 + z##N * S2)));                  \
                }                                                       \
                y[index] = (n##N & 2)? -f##N : f##N;                    \
                goto label;                                             \
        }

#define PROCESS(N)                                                      \
        if (medium) {                                                   \
                z##N = y##N * invpio2 + c3two51;                        \
                n##N = LO(z##N);                                        \
                z##N -= c3two51;                                        \
                y##N = (y##N - z##N * pio2_1) - z##N * pio2_t;          \
        }                                                               \
        z##N = y##N * y##N;                                             \
        if (n##N & 1) { /* compute cos y */                             \
                f##N = (float)(one + z##N * (mhalf + z##N * (C0 +       \
                    z##N * (C1 + z##N * C2))));                         \
        } else { /* compute sin y */                                    \
                f##N = (float)(y##N + y##N * z##N * (S0 + z##N * (S1 +  \
                    z##N * S2)));                                       \
        }                                                               \
        *y = (n##N & 2)? -f##N : f##N;                                  \
        y += stridey

void
__vsinf(int n, float *restrict x, int stridex, float *restrict y,
    int stridey)
{
        double          y0, y1, y2, y3;
        double          z0, z1, z2, z3;
        float           f0, f1, f2, f3, t;
        int             n0 = 0, n1 = 0, n2 = 0, n3, hx, ix, medium;

        y -= stridey;

        for (;;) {
begin:
                y += stridey;

                if (--n < 0)
                        break;

                medium = 0;
                PREPROCESS(0, 0, begin);

                if (--n < 0)
                        goto process1;

                PREPROCESS(1, stridey, process1);

                if (--n < 0)
                        goto process2;

                PREPROCESS(2, (stridey << 1), process2);

                if (--n < 0)
                        goto process3;

                PREPROCESS(3, (stridey << 1) + stridey, process3);

                if (medium) {
                        z0 = y0 * invpio2 + c3two51;
                        z1 = y1 * invpio2 + c3two51;
                        z2 = y2 * invpio2 + c3two51;
                        z3 = y3 * invpio2 + c3two51;

                        n0 = LO(z0);
                        n1 = LO(z1);
                        n2 = LO(z2);
                        n3 = LO(z3);

                        z0 -= c3two51;
                        z1 -= c3two51;
                        z2 -= c3two51;
                        z3 -= c3two51;

                        y0 = (y0 - z0 * pio2_1) - z0 * pio2_t;
                        y1 = (y1 - z1 * pio2_1) - z1 * pio2_t;
                        y2 = (y2 - z2 * pio2_1) - z2 * pio2_t;
                        y3 = (y3 - z3 * pio2_1) - z3 * pio2_t;
                }

                z0 = y0 * y0;
                z1 = y1 * y1;
                z2 = y2 * y2;
                z3 = y3 * y3;

                hx = (n0 & 1) | ((n1 & 1) << 1) | ((n2 & 1) << 2) |
                    ((n3 & 1) << 3);
                switch (hx) {
                case 0:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 1:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 2:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 3:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 4:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 5:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 6:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 7:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(y3 + y3 * z3 * (S0 + z3 * (S1 + z3 * S2)));
                        break;

                case 8:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 9:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 10:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 11:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(y2 + y2 * z2 * (S0 + z2 * (S1 + z2 * S2)));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 12:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 13:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(y1 + y1 * z1 * (S0 + z1 * (S1 + z1 * S2)));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                case 14:
                        f0 = (float)(y0 + y0 * z0 * (S0 + z0 * (S1 + z0 * S2)));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                        break;

                default:
                        f0 = (float)(one + z0 * (mhalf + z0 * (C0 +
                            z0 * (C1 + z0 * C2))));
                        f1 = (float)(one + z1 * (mhalf + z1 * (C0 +
                            z1 * (C1 + z1 * C2))));
                        f2 = (float)(one + z2 * (mhalf + z2 * (C0 +
                            z2 * (C1 + z2 * C2))));
                        f3 = (float)(one + z3 * (mhalf + z3 * (C0 +
                            z3 * (C1 + z3 * C2))));
                }

                *y = (n0 & 2)? -f0 : f0;
                y += stridey;
                *y = (n1 & 2)? -f1 : f1;
                y += stridey;
                *y = (n2 & 2)? -f2 : f2;
                y += stridey;
                *y = (n3 & 2)? -f3 : f3;
                continue;

process1:
                PROCESS(0);
                continue;

process2:
                PROCESS(0);
                PROCESS(1);
                continue;

process3:
                PROCESS(0);
                PROCESS(1);
                PROCESS(2);
        }
}