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    /* ===-- ctzdi2.c - Implement __ctzdi2 -------------------------------------===  | 
    
    
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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 __ctzdi2 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: the number of trailing 0-bits  */  | 
    
    
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    /* Precondition: a != 0 */  | 
    
    
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    COMPILER_RT_ABI si_int  | 
    
    
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    __ctzdi2(di_int a)  | 
    
    
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    { | 
    
    
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        dwords x;  | 
    
    
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        x.all = a;  | 
    
    
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        const si_int f = -(x.s.low == 0);  | 
    
    
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        return __builtin_ctz((x.s.high & f) | (x.s.low & ~f)) +  | 
    
    
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                  (f & ((si_int)(sizeof(si_int) * CHAR_BIT)));  | 
    
    
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    }  |