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/* ===-- ffsti2.c - Implement __ffsti2 -------------------------------------=== 
 * 
 *                     The LLVM Compiler Infrastructure 
 * 
 * This file is dual licensed under the MIT and the University of Illinois Open 
 * Source Licenses. See LICENSE.TXT for details. 
 * 
 * ===----------------------------------------------------------------------=== 
 * 
 * This file implements __ffsti2 for the compiler_rt library. 
 * 
 * ===----------------------------------------------------------------------=== 
 */ 
 
#include "int_lib.h" 
 
#ifdef CRT_HAS_128BIT 
 
/* Returns: the index of the least significant 1-bit in a, or 
 * the value zero if a is zero. The least significant bit is index one. 
 */ 
 
COMPILER_RT_ABI si_int 
__ffsti2(ti_int a) 
{ 
    twords x; 
    x.all = a; 
    if (x.s.low == 0) 
    { 
        if (x.s.high == 0) 
            return 0; 
        return __builtin_ctzll(x.s.high) + (1 + sizeof(di_int) * CHAR_BIT); 
    } 
    return __builtin_ctzll(x.s.low) + 1; 
} 
 
#endif /* CRT_HAS_128BIT */