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//===-- ffsti2.c - Implement __ffsti2 -------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __ffsti2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#if __x86_64
#include "int_lib.h"
// 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.
si_int
__ffsti2(ti_int a)
{
twords x;
x.all = a;
if (x.low == 0)
{
if (x.high == 0)
return 0;
return __builtin_ctzll(x.high) + (1 + sizeof(di_int) * CHAR_BIT);
}
return __builtin_ctzll(x.low) + 1;
}
#endif
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