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/*
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 * Utility compute operations used by translated code.
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 *
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 * Copyright (c) 2003 Fabrice Bellard
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 * Copyright (c) 2007 Aurelien Jarno
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a copy
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 * of this software and associated documentation files (the "Software"), to deal
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 * in the Software without restriction, including without limitation the rights
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 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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 * copies of the Software, and to permit persons to whom the Software is
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 * furnished to do so, subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included in
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 * all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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 * THE SOFTWARE.
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 */
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#include "exec.h"
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#include "host-utils.h"
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//#define DEBUG_MULDIV
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/* Long integer helpers */
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#if !defined(__x86_64__)
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static void add128 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
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{
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    *plow += a;
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    /* carry test */
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    if (*plow < a)
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        (*phigh)++;
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    *phigh += b;
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}
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static void neg128 (uint64_t *plow, uint64_t *phigh)
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{
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    *plow = ~*plow;
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    *phigh = ~*phigh;
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    add128(plow, phigh, 1, 0);
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}
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static void mul64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
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{
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    uint32_t a0, a1, b0, b1;
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    uint64_t v;
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    a0 = a;
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    a1 = a >> 32;
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    b0 = b;
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    b1 = b >> 32;
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    v = (uint64_t)a0 * (uint64_t)b0;
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    *plow = v;
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    *phigh = 0;
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    v = (uint64_t)a0 * (uint64_t)b1;
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    add128(plow, phigh, v << 32, v >> 32);
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    v = (uint64_t)a1 * (uint64_t)b0;
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    add128(plow, phigh, v << 32, v >> 32);
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    v = (uint64_t)a1 * (uint64_t)b1;
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    *phigh += v;
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}
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/* Unsigned 64x64 -> 128 multiplication */
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void mulu64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
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{
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    mul64(plow, phigh, a, b);
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#if defined(DEBUG_MULDIV)
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    printf("mulu64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n",
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           a, b, *phigh, *plow);
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#endif
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}
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/* Signed 64x64 -> 128 multiplication */
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void muls64 (uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b)
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{
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    int sa, sb;
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    sa = (a < 0);
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    if (sa)
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        a = -a;
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    sb = (b < 0);
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    if (sb)
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        b = -b;
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    mul64(plow, phigh, a, b);
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    if (sa ^ sb) {
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        neg128(plow, phigh);
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    }
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#if defined(DEBUG_MULDIV)
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    printf("muls64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n",
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           a, b, *phigh, *plow);
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#endif
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}
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#endif /* !defined(__x86_64__) */