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| //===-- ffsti2.c - Implement __ffsti2 -------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// 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
|