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//===-- clzti2.c - Implement __clzti2 -------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __clzti2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#if __x86_64
#include "int_lib.h"
// Returns: the number of leading 0-bits
// Precondition: a != 0
si_int
__clzti2(ti_int a)
{
twords x;
x.all = a;
const di_int f = -(x.high == 0);
return __builtin_clzll((x.high & ~f) | (x.low & f)) +
((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
}
#endif
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