target-tilegx: Add several helpers for instructions translation

/*

 * QEMU TILE-Gx helpers

 *

 *  Copyright (c) 2015 Chen Gang

 *

 * 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/lgpl-2.1.html>

 */

#include "cpu.h"

#include "qemu-common.h"

#include "exec/helper-proto.h"

void helper_exception(CPUTLGState *env, uint32_t excp)

{

    CPUState *cs = CPU(tilegx_env_get_cpu(env));

    cs->exception_index = excp;

    cpu_loop_exit(cs);

}

uint64_t helper_cntlz(uint64_t arg)

{

    return clz64(arg);

}

uint64_t helper_cnttz(uint64_t arg)

{

    return ctz64(arg);

}

/*

 * Functional Description

 *     uint64_t a = rf[SrcA];

 *     uint64_t b = rf[SrcB];

 *     uint64_t d = rf[Dest];

 *     uint64_t output = 0;

 *     unsigned int counter;

 *     for (counter = 0; counter < (WORD_SIZE / BYTE_SIZE); counter++)

 *     {

 *         int sel = getByte (b, counter) & 0xf;

 *         uint8_t byte = (sel < 8) ? getByte (d, sel) : getByte (a, (sel - 8));

 *         output = setByte (output, counter, byte);

 *     }

 *     rf[Dest] = output;

 */

uint64_t helper_shufflebytes(uint64_t dest, uint64_t srca, uint64_t srcb)

{

    uint64_t vdst = 0;

    int count;

    for (count = 0; count < 64; count += 8) {

        uint64_t sel = srcb >> count;

        uint64_t src = (sel & 8) ? srca : dest;

        vdst |= extract64(src, (sel & 7) * 8, 8) << count;

    }

    return vdst;

}

DEF_HELPER_2(exception, noreturn, env, i32)

DEF_HELPER_FLAGS_1(cntlz, TCG_CALL_NO_RWG_SE, i64, i64)

DEF_HELPER_FLAGS_1(cnttz, TCG_CALL_NO_RWG_SE, i64, i64)

DEF_HELPER_FLAGS_3(shufflebytes, TCG_CALL_NO_RWG_SE, i64, i64, i64, i64)