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/*

 *  x86 condition code 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 SIGN_MASK (((target_ulong)1) << (DATA_BITS - 1))

#if DATA_BITS == 8

#define SUFFIX b

#define DATA_TYPE uint8_t

#define DATA_MASK 0xff

#elif DATA_BITS == 16

#define SUFFIX w

#define DATA_TYPE uint16_t

#define DATA_MASK 0xffff

#elif DATA_BITS == 32

#define SUFFIX l

#define DATA_TYPE uint32_t

#define DATA_MASK 0xffffffff

#elif DATA_BITS == 64

#define SUFFIX q

#define DATA_TYPE uint64_t

#define DATA_MASK 0xffffffffffffffffULL

#else

#error unhandled operand size

#endif

/* dynamic flags computation */

static int glue(compute_all_add, SUFFIX)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    return CC_SRC;

}

#endif

static int glue(compute_all_dec, SUFFIX)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

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

}

#if DATA_BITS == 32

static int glue(compute_c_sar, SUFFIX)(CPUX86State *env)

{

    return CC_SRC & 1;

}

#endif

static int glue(compute_all_sar, SUFFIX)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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)(CPUX86State *env)

{

    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;

}

#undef DATA_BITS

#undef SIGN_MASK

#undef DATA_TYPE

#undef DATA_MASK

#undef SUFFIX