/*

 * Utility compute operations used by translated code.

 *

 * Copyright (c) 2007 Thiemo Seufer

 * Copyright (c) 2007 Jocelyn Mayer

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "osdep.h"

#if defined(__x86_64__)

#define __HAVE_FAST_MULU64__

static always_inline void mulu64 (uint64_t *plow, uint64_t *phigh,

                                  uint64_t a, uint64_t b)

{

    __asm__ ("mul %0\n\t"

             : "=d" (*phigh), "=a" (*plow)

             : "a" (a), "0" (b));

}

#define __HAVE_FAST_MULS64__

static always_inline void muls64 (uint64_t *plow, uint64_t *phigh,

                                  int64_t a, int64_t b)

{

    __asm__ ("imul %0\n\t"

             : "=d" (*phigh), "=a" (*plow)

             : "a" (a), "0" (b));

}

#else

void muls64(uint64_t *phigh, uint64_t *plow, int64_t a, int64_t b);

void mulu64(uint64_t *phigh, uint64_t *plow, uint64_t a, uint64_t b);

#endif

/* Binary search for leading zeros.  */

static always_inline int clz32(uint32_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    if (val)

        return __builtin_clz(val);

    else

        return 32;

#else

    int cnt = 0;

    if (!(val & 0xFFFF0000U)) {

        cnt += 16;

        val <<= 16;

    }

    if (!(val & 0xFF000000U)) {

        cnt += 8;

        val <<= 8;

    }

    if (!(val & 0xF0000000U)) {

        cnt += 4;

        val <<= 4;

    }

    if (!(val & 0xC0000000U)) {

        cnt += 2;

        val <<= 2;

    }

    if (!(val & 0x80000000U)) {

        cnt++;

        val <<= 1;

    }

    if (!(val & 0x80000000U)) {

        cnt++;

    }

    return cnt;

#endif

}

static always_inline int clo32(uint32_t val)

{

    return clz32(~val);

}

static always_inline int clz64(uint64_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    if (val)

        return __builtin_clzll(val);

    else

        return 64;

#else

    int cnt = 0;

    if (!(val >> 32)) {

        cnt += 32;

    } else {

        val >>= 32;

    }

    return cnt + clz32(val);

#endif

}

static always_inline int clo64(uint64_t val)

{

    return clz64(~val);

}

static always_inline int ctz32(uint32_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    if (val)

        return __builtin_ctz(val);

    else

        return 32;

#else

    int cnt;

    cnt = 0;

    if (!(val & 0x0000FFFFUL)) {

        cnt += 16;

        val >>= 16;

    }

    if (!(val & 0x000000FFUL)) {

        cnt += 8;

        val >>= 8;

    }

    if (!(val & 0x0000000FUL)) {

        cnt += 4;

        val >>= 4;

    }

    if (!(val & 0x00000003UL)) {

        cnt += 2;

        val >>= 2;

    }

    if (!(val & 0x00000001UL)) {

        cnt++;

        val >>= 1;

    }

    if (!(val & 0x00000001UL)) {

        cnt++;

    }

    return cnt;

#endif

}

static always_inline int cto32(uint32_t val)

{

    return ctz32(~val);

}

static always_inline int ctz64(uint64_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    if (val)

        return __builtin_ctz(val);

    else

        return 64;

#else

    int cnt;

    cnt = 0;

    if (!((uint32_t)val)) {

        cnt += 32;

        val >>= 32;

    }

    return cnt + ctz32(val);

#endif

}

static always_inline int cto64(uint64_t val)

{

    return ctz64(~val);

}

static always_inline int ctpop8(uint8_t val)

{

    val = (val & 0x55) + ((val >> 1) & 0x55);

    val = (val & 0x33) + ((val >> 2) & 0x33);

    val = (val & 0x0f) + ((val >> 4) & 0x0f);

    return val;

}

static always_inline int ctpop16(uint16_t val)

{

    val = (val & 0x5555) + ((val >> 1) & 0x5555);

    val = (val & 0x3333) + ((val >> 2) & 0x3333);

    val = (val & 0x0f0f) + ((val >> 4) & 0x0f0f);

    val = (val & 0x00ff) + ((val >> 8) & 0x00ff);

    return val;

}

static always_inline int ctpop32(uint32_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    return __builtin_popcount(val);

#else

    val = (val & 0x55555555) + ((val >>  1) & 0x55555555);

    val = (val & 0x33333333) + ((val >>  2) & 0x33333333);

    val = (val & 0x0f0f0f0f) + ((val >>  4) & 0x0f0f0f0f);

    val = (val & 0x00ff00ff) + ((val >>  8) & 0x00ff00ff);

    val = (val & 0x0000ffff) + ((val >> 16) & 0x0000ffff);

    return val;

#endif

}

static always_inline int ctpop64(uint64_t val)

{

#if QEMU_GNUC_PREREQ(3, 4)

    return __builtin_popcountll(val);

#else

    val = (val & 0x5555555555555555ULL) + ((val >>  1) & 0x5555555555555555ULL);

    val = (val & 0x3333333333333333ULL) + ((val >>  2) & 0x3333333333333333ULL);

    val = (val & 0x0f0f0f0f0f0f0f0fULL) + ((val >>  4) & 0x0f0f0f0f0f0f0f0fULL);

    val = (val & 0x00ff00ff00ff00ffULL) + ((val >>  8) & 0x00ff00ff00ff00ffULL);

    val = (val & 0x0000ffff0000ffffULL) + ((val >> 16) & 0x0000ffff0000ffffULL);

    val = (val & 0x00000000ffffffffULL) + ((val >> 32) & 0x00000000ffffffffULL);

    return val;

#endif

}