Archipelago » qemu

/*

 *  Misc Sparc 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 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 "cpu.h"

#include "qemu/host-utils.h"

#include "helper.h"

#include "sysemu.h"

void helper_raise_exception(CPUSPARCState *env, int tt)

{

    env->exception_index = tt;

    cpu_loop_exit(env);

}

void helper_debug(CPUSPARCState *env)

{

    env->exception_index = EXCP_DEBUG;

    cpu_loop_exit(env);

}

#ifdef TARGET_SPARC64

target_ulong helper_popc(target_ulong val)

{

    return ctpop64(val);

}

void helper_tick_set_count(void *opaque, uint64_t count)

{

#if !defined(CONFIG_USER_ONLY)

    cpu_tick_set_count(opaque, count);

#endif

}

uint64_t helper_tick_get_count(void *opaque)

{

#if !defined(CONFIG_USER_ONLY)

    return cpu_tick_get_count(opaque);

#else

    return 0;

#endif

}

void helper_tick_set_limit(void *opaque, uint64_t limit)

{

#if !defined(CONFIG_USER_ONLY)

    cpu_tick_set_limit(opaque, limit);

#endif

}

#endif

static target_ulong helper_udiv_common(CPUSPARCState *env, target_ulong a,

                                       target_ulong b, int cc)

{

    int overflow = 0;

    uint64_t x0;

    uint32_t x1;

    x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);

    x1 = (b & 0xffffffff);

    if (x1 == 0) {

        cpu_restore_state(env, GETPC());

        helper_raise_exception(env, TT_DIV_ZERO);

    }

    x0 = x0 / x1;

    if (x0 > 0xffffffff) {

        x0 = 0xffffffff;

        overflow = 1;

    }

    if (cc) {

        env->cc_dst = x0;

        env->cc_src2 = overflow;

        env->cc_op = CC_OP_DIV;

    }

    return x0;

}

target_ulong helper_udiv(CPUSPARCState *env, target_ulong a, target_ulong b)

{

    return helper_udiv_common(env, a, b, 0);

}

target_ulong helper_udiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)

{

    return helper_udiv_common(env, a, b, 1);

}

static target_ulong helper_sdiv_common(CPUSPARCState *env, target_ulong a,

                                       target_ulong b, int cc)

{

    int overflow = 0;

    int64_t x0;

    int32_t x1;

    x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);

    x1 = (b & 0xffffffff);

    if (x1 == 0) {

        cpu_restore_state(env, GETPC());

        helper_raise_exception(env, TT_DIV_ZERO);

    }

    x0 = x0 / x1;

    if ((int32_t) x0 != x0) {

        x0 = x0 < 0 ? 0x80000000 : 0x7fffffff;

        overflow = 1;

    }

    if (cc) {

        env->cc_dst = x0;

        env->cc_src2 = overflow;

        env->cc_op = CC_OP_DIV;

    }

    return x0;

}

target_ulong helper_sdiv(CPUSPARCState *env, target_ulong a, target_ulong b)

{

    return helper_sdiv_common(env, a, b, 0);

}

target_ulong helper_sdiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)

{

    return helper_sdiv_common(env, a, b, 1);

}

#ifdef TARGET_SPARC64

int64_t helper_sdivx(CPUSPARCState *env, int64_t a, int64_t b)

{

    if (b == 0) {

        /* Raise divide by zero trap.  */

        cpu_restore_state(env, GETPC());

        helper_raise_exception(env, TT_DIV_ZERO);

    } else if (b == -1) {

        /* Avoid overflow trap with i386 divide insn.  */

        return -a;

    } else {

        return a / b;

    }

}

uint64_t helper_udivx(CPUSPARCState *env, uint64_t a, uint64_t b)

{

    if (b == 0) {

        /* Raise divide by zero trap.  */

        cpu_restore_state(env, GETPC());

        helper_raise_exception(env, TT_DIV_ZERO);

    }

    return a / b;

}

#endif

target_ulong helper_taddcctv(CPUSPARCState *env, target_ulong src1,

                             target_ulong src2)

{

    target_ulong dst;

    /* Tag overflow occurs if either input has bits 0 or 1 set.  */

    if ((src1 | src2) & 3) {

        goto tag_overflow;

    }

    dst = src1 + src2;

    /* Tag overflow occurs if the addition overflows.  */

    if (~(src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {

        goto tag_overflow;

    }

    /* Only modify the CC after any exceptions have been generated.  */

    env->cc_op = CC_OP_TADDTV;

    env->cc_src = src1;

    env->cc_src2 = src2;

    env->cc_dst = dst;

    return dst;

 tag_overflow:

    cpu_restore_state(env, GETPC());

    helper_raise_exception(env, TT_TOVF);

}

target_ulong helper_tsubcctv(CPUSPARCState *env, target_ulong src1,

                             target_ulong src2)

{

    target_ulong dst;

    /* Tag overflow occurs if either input has bits 0 or 1 set.  */

    if ((src1 | src2) & 3) {

        goto tag_overflow;

    }

    dst = src1 - src2;

    /* Tag overflow occurs if the subtraction overflows.  */

    if ((src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {

        goto tag_overflow;

    }

    /* Only modify the CC after any exceptions have been generated.  */

    env->cc_op = CC_OP_TSUBTV;

    env->cc_src = src1;

    env->cc_src2 = src2;

    env->cc_dst = dst;

    return dst;

 tag_overflow:

    cpu_restore_state(env, GETPC());

    helper_raise_exception(env, TT_TOVF);

}