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/* ===-- clzti2.c - Implement __clzti2 -------------------------------------=== 
 * 
 *      	       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 __clzti2 for the compiler_rt library. 
 * 
 * ===----------------------------------------------------------------------=== 
 */ 
 
#include "int_lib.h" 
 
#ifdef CRT_HAS_128BIT 
 
/* Returns: the number of leading 0-bits */ 
 
/* Precondition: a != 0 */ 
 
COMPILER_RT_ABI si_int 
__clzti2(ti_int a) 
{ 
    twords x; 
    x.all = a; 
    const di_int f = -(x.s.high == 0); 
    return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) + 
           ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); 
} 
 
#endif /* CRT_HAS_128BIT */