/*
 * VIS op helpers
 *
 *  Copyright (c) 2003-2005 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/helper-proto.h"

target_ulong helper_array8(target_ulong rs1, target_ulong rs2)
{
    /*
     * From Oracle SPARC Architecture 2015:
     * Architecturally, an illegal R[rs2] value (>5) causes the array
     * instructions to produce undefined results. For historic reference,
     * past implementations of these instructions have ignored R[rs2]{63:3}
     * and have treated R[rs2] values of 6 and 7 as if they were 5.
     */
    target_ulong n = MIN(rs2 & 7, 5);

    target_ulong x_int = (rs1 >> 11) & 0x7ff;
    target_ulong y_int = (rs1 >> 33) & 0x7ff;
    target_ulong z_int = rs1 >> 55;

    target_ulong lower_x = x_int & 3;
    target_ulong lower_y = y_int & 3;
    target_ulong lower_z = z_int & 1;

    target_ulong middle_x = (x_int >> 2) & 15;
    target_ulong middle_y = (y_int >> 2) & 15;
    target_ulong middle_z = (z_int >> 1) & 15;

    target_ulong upper_x = (x_int >> 6) & ((1 << n) - 1);
    target_ulong upper_y = (y_int >> 6) & ((1 << n) - 1);
    target_ulong upper_z = z_int >> 5;

    return (upper_z << (17 + 2 * n))
         | (upper_y << (17 + n))
         | (upper_x << 17)
         | (middle_z << 13)
         | (middle_y << 9)
         | (middle_x << 5)
         | (lower_z << 4)
         | (lower_y << 2)
         | lower_x;
}

#if HOST_BIG_ENDIAN
#define VIS_B64(n) b[7 - (n)]
#define VIS_SB64(n) sb[7 - (n)]
#define VIS_W64(n) w[3 - (n)]
#define VIS_SW64(n) sw[3 - (n)]
#define VIS_L64(n) l[1 - (n)]
#define VIS_B32(n) b[3 - (n)]
#define VIS_W32(n) w[1 - (n)]
#else
#define VIS_B64(n) b[n]
#define VIS_SB64(n) sb[n]
#define VIS_W64(n) w[n]
#define VIS_SW64(n) sw[n]
#define VIS_L64(n) l[n]
#define VIS_B32(n) b[n]
#define VIS_W32(n) w[n]
#endif

typedef union {
    uint8_t b[8];
    int8_t sb[8];
    uint16_t w[4];
    int16_t sw[4];
    uint32_t l[2];
    uint64_t ll;
    float64 d;
} VIS64;

typedef union {
    uint8_t b[4];
    uint16_t w[2];
    uint32_t l;
    float32 f;
} VIS32;

uint64_t helper_fpmerge(uint32_t src1, uint32_t src2)
{
    VIS32 s1, s2;
    VIS64 d;

    s1.l = src1;
    s2.l = src2;
    d.ll = 0;

    d.VIS_B64(7) = s1.VIS_B32(3);
    d.VIS_B64(6) = s2.VIS_B32(3);
    d.VIS_B64(5) = s1.VIS_B32(2);
    d.VIS_B64(4) = s2.VIS_B32(2);
    d.VIS_B64(3) = s1.VIS_B32(1);
    d.VIS_B64(2) = s2.VIS_B32(1);
    d.VIS_B64(1) = s1.VIS_B32(0);
    d.VIS_B64(0) = s2.VIS_B32(0);

    return d.ll;
}

static inline int do_ms16b(int x, int y)
{
    return ((x * y) + 0x80) >> 8;
}

uint64_t helper_fmul8x16(uint32_t src1, uint64_t src2)
{
    VIS64 d;
    VIS32 s;

    s.l = src1;
    d.ll = src2;

    d.VIS_W64(0) = do_ms16b(s.VIS_B32(0), d.VIS_SW64(0));
    d.VIS_W64(1) = do_ms16b(s.VIS_B32(1), d.VIS_SW64(1));
    d.VIS_W64(2) = do_ms16b(s.VIS_B32(2), d.VIS_SW64(2));
    d.VIS_W64(3) = do_ms16b(s.VIS_B32(3), d.VIS_SW64(3));

    return d.ll;
}

uint64_t helper_fmul8x16a(uint32_t src1, int32_t src2)
{
    VIS32 s;
    VIS64 d;

    s.l = src1;
    d.ll = 0;

    d.VIS_W64(0) = do_ms16b(s.VIS_B32(0), src2);
    d.VIS_W64(1) = do_ms16b(s.VIS_B32(1), src2);
    d.VIS_W64(2) = do_ms16b(s.VIS_B32(2), src2);
    d.VIS_W64(3) = do_ms16b(s.VIS_B32(3), src2);

    return d.ll;
}

uint64_t helper_fmul8sux16(uint64_t src1, uint64_t src2)
{
    VIS64 s, d;

    s.ll = src1;
    d.ll = src2;

    d.VIS_W64(0) = do_ms16b(s.VIS_SB64(1), d.VIS_SW64(0));
    d.VIS_W64(1) = do_ms16b(s.VIS_SB64(3), d.VIS_SW64(1));
    d.VIS_W64(2) = do_ms16b(s.VIS_SB64(5), d.VIS_SW64(2));
    d.VIS_W64(3) = do_ms16b(s.VIS_SB64(7), d.VIS_SW64(3));

    return d.ll;
}

uint64_t helper_fmul8ulx16(uint64_t src1, uint64_t src2)
{
    VIS64 s, d;

    s.ll = src1;
    d.ll = src2;

    d.VIS_W64(0) = (s.VIS_B64(0) * d.VIS_SW64(0) + 0x8000) >> 16;
    d.VIS_W64(1) = (s.VIS_B64(2) * d.VIS_SW64(1) + 0x8000) >> 16;
    d.VIS_W64(2) = (s.VIS_B64(4) * d.VIS_SW64(2) + 0x8000) >> 16;
    d.VIS_W64(3) = (s.VIS_B64(6) * d.VIS_SW64(3) + 0x8000) >> 16;

    return d.ll;
}

uint64_t helper_fexpand(uint32_t src2)
{
    VIS32 s;
    VIS64 d;

    s.l = src2;
    d.ll = 0;
    d.VIS_W64(0) = s.VIS_B32(0) << 4;
    d.VIS_W64(1) = s.VIS_B32(1) << 4;
    d.VIS_W64(2) = s.VIS_B32(2) << 4;
    d.VIS_W64(3) = s.VIS_B32(3) << 4;

    return d.ll;
}

#define VIS_CMPHELPER(name, F)                                    \
    uint64_t name##16(uint64_t src1, uint64_t src2)               \
    {                                                             \
        VIS64 s, d;                                               \
                                                                  \
        s.ll = src1;                                              \
        d.ll = src2;                                              \
                                                                  \
        d.VIS_W64(0) = F(s.VIS_W64(0), d.VIS_W64(0)) ? 1 : 0;     \
        d.VIS_W64(0) |= F(s.VIS_W64(1), d.VIS_W64(1)) ? 2 : 0;    \
        d.VIS_W64(0) |= F(s.VIS_W64(2), d.VIS_W64(2)) ? 4 : 0;    \
        d.VIS_W64(0) |= F(s.VIS_W64(3), d.VIS_W64(3)) ? 8 : 0;    \
        d.VIS_W64(1) = d.VIS_W64(2) = d.VIS_W64(3) = 0;           \
                                                                  \
        return d.ll;                                              \
    }                                                             \
                                                                  \
    uint64_t name##32(uint64_t src1, uint64_t src2)               \
    {                                                             \
        VIS64 s, d;                                               \
                                                                  \
        s.ll = src1;                                              \
        d.ll = src2;                                              \
                                                                  \
        d.VIS_L64(0) = F(s.VIS_L64(0), d.VIS_L64(0)) ? 1 : 0;     \
        d.VIS_L64(0) |= F(s.VIS_L64(1), d.VIS_L64(1)) ? 2 : 0;    \
        d.VIS_L64(1) = 0;                                         \
                                                                  \
        return d.ll;                                              \
    }

#define FCMPGT(a, b) ((a) > (b))
#define FCMPEQ(a, b) ((a) == (b))
#define FCMPLE(a, b) ((a) <= (b))
#define FCMPNE(a, b) ((a) != (b))

VIS_CMPHELPER(helper_fcmpgt, FCMPGT)
VIS_CMPHELPER(helper_fcmpeq, FCMPEQ)
VIS_CMPHELPER(helper_fcmple, FCMPLE)
VIS_CMPHELPER(helper_fcmpne, FCMPNE)

uint64_t helper_pdist(uint64_t sum, uint64_t src1, uint64_t src2)
{
    int i;
    for (i = 0; i < 8; i++) {
        int s1, s2;

        s1 = (src1 >> (56 - (i * 8))) & 0xff;
        s2 = (src2 >> (56 - (i * 8))) & 0xff;

        /* Absolute value of difference. */
        s1 -= s2;
        if (s1 < 0) {
            s1 = -s1;
        }

        sum += s1;
    }

    return sum;
}

uint32_t helper_fpack16(uint64_t gsr, uint64_t rs2)
{
    int scale = (gsr >> 3) & 0xf;
    uint32_t ret = 0;
    int byte;

    for (byte = 0; byte < 4; byte++) {
        uint32_t val;
        int16_t src = rs2 >> (byte * 16);
        int32_t scaled = src << scale;
        int32_t from_fixed = scaled >> 7;

        val = (from_fixed < 0 ?  0 :
               from_fixed > 255 ?  255 : from_fixed);

        ret |= val << (8 * byte);
    }

    return ret;
}

uint64_t helper_fpack32(uint64_t gsr, uint64_t rs1, uint64_t rs2)
{
    int scale = (gsr >> 3) & 0x1f;
    uint64_t ret = 0;
    int word;

    ret = (rs1 << 8) & ~(0x000000ff000000ffULL);
    for (word = 0; word < 2; word++) {
        uint64_t val;
        int32_t src = rs2 >> (word * 32);
        int64_t scaled = (int64_t)src << scale;
        int64_t from_fixed = scaled >> 23;

        val = (from_fixed < 0 ? 0 :
               (from_fixed > 255) ? 255 : from_fixed);

        ret |= val << (32 * word);
    }

    return ret;
}

uint32_t helper_fpackfix(uint64_t gsr, uint64_t rs2)
{
    int scale = (gsr >> 3) & 0x1f;
    uint32_t ret = 0;
    int word;

    for (word = 0; word < 2; word++) {
        uint32_t val;
        int32_t src = rs2 >> (word * 32);
        int64_t scaled = (int64_t)src << scale;
        int64_t from_fixed = scaled >> 16;

        val = (from_fixed < -32768 ? -32768 :
               from_fixed > 32767 ?  32767 : from_fixed);

        ret |= (val & 0xffff) << (word * 16);
    }

    return ret;
}

uint64_t helper_bshuffle(uint64_t gsr, uint64_t src1, uint64_t src2)
{
    union {
        uint64_t ll[2];
        uint8_t b[16];
    } s;
    VIS64 r;
    uint32_t i, mask, host;

    /* Set up S such that we can index across all of the bytes.  */
#if HOST_BIG_ENDIAN
    s.ll[0] = src1;
    s.ll[1] = src2;
    host = 0;
#else
    s.ll[1] = src1;
    s.ll[0] = src2;
    host = 15;
#endif
    mask = gsr >> 32;

    for (i = 0; i < 8; ++i) {
        unsigned e = (mask >> (28 - i*4)) & 0xf;
        r.VIS_B64(i) = s.b[e ^ host];
    }

    return r.ll;
}