GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcompiler_rt/udivsi3.c Lines: 0 19 0.0 %
Date: 2017-11-13 Branches: 0 10 0.0 %

Line Branch Exec Source
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/* ===-- udivsi3.c - Implement __udivsi3 -----------------------------------===
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 *
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 *                     The LLVM Compiler Infrastructure
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 *
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 * This file is dual licensed under the MIT and the University of Illinois Open
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 * Source Licenses. See LICENSE.TXT for details.
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 *
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 * ===----------------------------------------------------------------------===
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 *
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 * This file implements __udivsi3 for the compiler_rt library.
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 *
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 * ===----------------------------------------------------------------------===
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 */
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#include "int_lib.h"
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/* Returns: a / b */
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/* Translated from Figure 3-40 of The PowerPC Compiler Writer's Guide */
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ARM_EABI_FNALIAS(uidiv, udivsi3)
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/* This function should not call __divsi3! */
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COMPILER_RT_ABI su_int
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__udivsi3(su_int n, su_int d)
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{
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    const unsigned n_uword_bits = sizeof(su_int) * CHAR_BIT;
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    su_int q;
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    su_int r;
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    unsigned sr;
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    /* special cases */
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    if (d == 0)
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        return 0; /* ?! */
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    if (n == 0)
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        return 0;
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    sr = __builtin_clz(d) - __builtin_clz(n);
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    /* 0 <= sr <= n_uword_bits - 1 or sr large */
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    if (sr > n_uword_bits - 1)  /* d > r */
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        return 0;
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    if (sr == n_uword_bits - 1)  /* d == 1 */
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        return n;
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    ++sr;
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    /* 1 <= sr <= n_uword_bits - 1 */
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    /* Not a special case */
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    q = n << (n_uword_bits - sr);
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    r = n >> sr;
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    su_int carry = 0;
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    for (; sr > 0; --sr)
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    {
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        /* r:q = ((r:q)  << 1) | carry */
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        r = (r << 1) | (q >> (n_uword_bits - 1));
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        q = (q << 1) | carry;
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        /* carry = 0;
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         * if (r.all >= d.all)
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         * {
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         *      r.all -= d.all;
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         *      carry = 1;
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         * }
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         */
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        const si_int s = (si_int)(d - r - 1) >> (n_uword_bits - 1);
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        carry = s & 1;
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        r -= d & s;
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    }
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    q = (q << 1) | carry;
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    return q;
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}