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    /* ===-- powidf2.cpp - Implement __powidf2 ---------------------------------===  | 
    
    
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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 __powidf2 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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    COMPILER_RT_ABI double  | 
    
    
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    __powidf2(double a, si_int b)  | 
    
    
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    { | 
    
    
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        const int recip = b < 0;  | 
    
    
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        double r = 1;  | 
    
    
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        while (1)  | 
    
    
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        { | 
    
    
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            if (b & 1)  | 
    
    
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                r *= a;  | 
    
    
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            b /= 2;  | 
    
    
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            if (b == 0)  | 
    
    
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                break;  | 
    
    
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            a *= a;  | 
    
    
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        }  | 
    
    
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        return recip ? 1/r : r;  | 
    
    
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    }  |