Archipelago » qemu

/*

 *  i386 helpers

 *

 *  Copyright (c) 2008 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 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/>.

 */

#define DATA_BITS (1 << (3 + SHIFT))

#define SHIFT_MASK (DATA_BITS - 1)

#define SIGN_MASK (((target_ulong)1) << (DATA_BITS - 1))

#if DATA_BITS <= 32

#define SHIFT1_MASK 0x1f

#else

#define SHIFT1_MASK 0x3f

#endif

#if DATA_BITS == 8

#define SUFFIX b

#define DATA_TYPE uint8_t

#define DATA_STYPE int8_t

#define DATA_MASK 0xff

#elif DATA_BITS == 16

#define SUFFIX w

#define DATA_TYPE uint16_t

#define DATA_STYPE int16_t

#define DATA_MASK 0xffff

#elif DATA_BITS == 32

#define SUFFIX l

#define DATA_TYPE uint32_t

#define DATA_STYPE int32_t

#define DATA_MASK 0xffffffff

#elif DATA_BITS == 64

#define SUFFIX q

#define DATA_TYPE uint64_t

#define DATA_STYPE int64_t

#define DATA_MASK 0xffffffffffffffffULL

#else

#error unhandled operand size

#endif

/* dynamic flags computation */

static int glue(compute_all_add, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_SRC;

    src2 = CC_DST - CC_SRC;

    cf = (DATA_TYPE)CC_DST < (DATA_TYPE)src1;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = lshift((src1 ^ src2 ^ -1) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_add, SUFFIX)(void)

{

    int cf;

    target_long src1;

    src1 = CC_SRC;

    cf = (DATA_TYPE)CC_DST < (DATA_TYPE)src1;

    return cf;

}

static int glue(compute_all_adc, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_SRC;

    src2 = CC_DST - CC_SRC - 1;

    cf = (DATA_TYPE)CC_DST <= (DATA_TYPE)src1;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = lshift((src1 ^ src2 ^ -1) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_adc, SUFFIX)(void)

{

    int cf;

    target_long src1;

    src1 = CC_SRC;

    cf = (DATA_TYPE)CC_DST <= (DATA_TYPE)src1;

    return cf;

}

static int glue(compute_all_sub, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_DST + CC_SRC;

    src2 = CC_SRC;

    cf = (DATA_TYPE)src1 < (DATA_TYPE)src2;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = lshift((src1 ^ src2) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_sub, SUFFIX)(void)

{

    int cf;

    target_long src1, src2;

    src1 = CC_DST + CC_SRC;

    src2 = CC_SRC;

    cf = (DATA_TYPE)src1 < (DATA_TYPE)src2;

    return cf;

}

static int glue(compute_all_sbb, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_DST + CC_SRC + 1;

    src2 = CC_SRC;

    cf = (DATA_TYPE)src1 <= (DATA_TYPE)src2;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = lshift((src1 ^ src2) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_sbb, SUFFIX)(void)

{

    int cf;

    target_long src1, src2;

    src1 = CC_DST + CC_SRC + 1;

    src2 = CC_SRC;

    cf = (DATA_TYPE)src1 <= (DATA_TYPE)src2;

    return cf;

}

static int glue(compute_all_logic, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    cf = 0;

    pf = parity_table[(uint8_t)CC_DST];

    af = 0;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = 0;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_logic, SUFFIX)(void)

{

    return 0;

}

static int glue(compute_all_inc, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_DST - 1;

    src2 = 1;

    cf = CC_SRC;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = ((CC_DST & DATA_MASK) == SIGN_MASK) << 11;

    return cf | pf | af | zf | sf | of;

}

#if DATA_BITS == 32

static int glue(compute_c_inc, SUFFIX)(void)

{

    return CC_SRC;

}

#endif

static int glue(compute_all_dec, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    target_long src1, src2;

    src1 = CC_DST + 1;

    src2 = 1;

    cf = CC_SRC;

    pf = parity_table[(uint8_t)CC_DST];

    af = (CC_DST ^ src1 ^ src2) & 0x10;

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = ((CC_DST & DATA_MASK) == ((target_ulong)SIGN_MASK - 1)) << 11;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_all_shl, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    cf = (CC_SRC >> (DATA_BITS - 1)) & CC_C;

    pf = parity_table[(uint8_t)CC_DST];

    af = 0; /* undefined */

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    /* of is defined if shift count == 1 */

    of = lshift(CC_SRC ^ CC_DST, 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

static int glue(compute_c_shl, SUFFIX)(void)

{

    return (CC_SRC >> (DATA_BITS - 1)) & CC_C;

}

#if DATA_BITS == 32

static int glue(compute_c_sar, SUFFIX)(void)

{

    return CC_SRC & 1;

}

#endif

static int glue(compute_all_sar, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    cf = CC_SRC & 1;

    pf = parity_table[(uint8_t)CC_DST];

    af = 0; /* undefined */

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    /* of is defined if shift count == 1 */

    of = lshift(CC_SRC ^ CC_DST, 12 - DATA_BITS) & CC_O;

    return cf | pf | af | zf | sf | of;

}

#if DATA_BITS == 32

static int glue(compute_c_mul, SUFFIX)(void)

{

    int cf;

    cf = (CC_SRC != 0);

    return cf;

}

#endif

/* NOTE: we compute the flags like the P4. On olders CPUs, only OF and

   CF are modified and it is slower to do that. */

static int glue(compute_all_mul, SUFFIX)(void)

{

    int cf, pf, af, zf, sf, of;

    cf = (CC_SRC != 0);

    pf = parity_table[(uint8_t)CC_DST];

    af = 0; /* undefined */

    zf = ((DATA_TYPE)CC_DST == 0) << 6;

    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;

    of = cf << 11;

    return cf | pf | af | zf | sf | of;

}

/* shifts */

target_ulong glue(helper_rcl, SUFFIX)(target_ulong t0, target_ulong t1)

{

    int count, eflags;

    target_ulong src;

    target_long res;

    count = t1 & SHIFT1_MASK;

#if DATA_BITS == 16

    count = rclw_table[count];

#elif DATA_BITS == 8

    count = rclb_table[count];

#endif

    if (count) {

        eflags = helper_cc_compute_all(CC_OP);

        t0 &= DATA_MASK;

        src = t0;

        res = (t0 << count) | ((target_ulong)(eflags & CC_C) << (count - 1));

        if (count > 1)

            res |= t0 >> (DATA_BITS + 1 - count);

        t0 = res;

        env->cc_tmp = (eflags & ~(CC_C | CC_O)) |

            (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |

            ((src >> (DATA_BITS - count)) & CC_C);

    } else {

        env->cc_tmp = -1;

    }

    return t0;

}

target_ulong glue(helper_rcr, SUFFIX)(target_ulong t0, target_ulong t1)

{

    int count, eflags;

    target_ulong src;

    target_long res;

    count = t1 & SHIFT1_MASK;

#if DATA_BITS == 16

    count = rclw_table[count];

#elif DATA_BITS == 8

    count = rclb_table[count];

#endif

    if (count) {

        eflags = helper_cc_compute_all(CC_OP);

        t0 &= DATA_MASK;

        src = t0;

        res = (t0 >> count) | ((target_ulong)(eflags & CC_C) << (DATA_BITS - count));

        if (count > 1)

            res |= t0 << (DATA_BITS + 1 - count);

        t0 = res;

        env->cc_tmp = (eflags & ~(CC_C | CC_O)) |

            (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |

            ((src >> (count - 1)) & CC_C);

    } else {

        env->cc_tmp = -1;

    }

    return t0;

}

#undef DATA_BITS

#undef SHIFT_MASK

#undef SHIFT1_MASK

#undef SIGN_MASK

#undef DATA_TYPE

#undef DATA_STYPE

#undef DATA_MASK

#undef SUFFIX