GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcompiler_rt/mulvti3.c Lines: 0 20 0.0 %
Date: 2017-11-13 Branches: 0 16 0.0 %

Line Branch Exec Source
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/* ===-- mulvti3.c - Implement __mulvti3 -----------------------------------===
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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 __mulvti3 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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#ifdef CRT_HAS_128BIT
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/* Returns: a * b */
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/* Effects: aborts if a * b overflows */
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COMPILER_RT_ABI ti_int
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__mulvti3(ti_int a, ti_int b)
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{
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    const int N = (int)(sizeof(ti_int) * CHAR_BIT);
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    const ti_int MIN = (ti_int)1 << (N-1);
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    const ti_int MAX = ~MIN;
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    if (a == MIN)
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    {
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        if (b == 0 || b == 1)
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            return a * b;
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        compilerrt_abort();
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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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            return a * b;
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        compilerrt_abort();
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    }
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    ti_int sa = a >> (N - 1);
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    ti_int abs_a = (a ^ sa) - sa;
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    ti_int sb = b >> (N - 1);
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    ti_int abs_b = (b ^ sb) - sb;
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    if (abs_a < 2 || abs_b < 2)
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        return a * b;
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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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            compilerrt_abort();
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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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            compilerrt_abort();
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    }
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    return a * b;
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}
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#endif /* CRT_HAS_128BIT */