GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcompiler_rt/mulosi4.c Lines: 0 22 0.0 %
Date: 2017-11-13 Branches: 0 16 0.0 %

Line Branch Exec Source
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/*===-- mulosi4.c - Implement __mulosi4 -----------------------------------===
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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 __mulosi4 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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/* Effects: sets *overflow to 1  if a * b overflows */
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COMPILER_RT_ABI si_int
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__mulosi4(si_int a, si_int b, int* overflow)
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{
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    const int N = (int)(sizeof(si_int) * CHAR_BIT);
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    const si_int MIN = (si_int)1 << (N-1);
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    const si_int MAX = ~MIN;
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    *overflow = 0;
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    si_int result = a * b;
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    if (a == MIN)
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    {
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        if (b != 0 && b != 1)
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	    *overflow = 1;
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	return result;
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    }
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    if (b == MIN)
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    {
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        if (a != 0 && a != 1)
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	    *overflow = 1;
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        return result;
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    }
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    si_int sa = a >> (N - 1);
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    si_int abs_a = (a ^ sa) - sa;
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    si_int sb = b >> (N - 1);
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    si_int abs_b = (b ^ sb) - sb;
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    if (abs_a < 2 || abs_b < 2)
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        return result;
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    if (sa == sb)
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    {
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        if (abs_a > MAX / abs_b)
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            *overflow = 1;
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    }
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    else
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    {
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        if (abs_a > MIN / -abs_b)
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            *overflow = 1;
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    }
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    return result;
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}