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1//===-- ffsdi2.c - Implement __ffsdi2 -------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements __ffsdi2 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15// Returns: the index of the least significant 1-bit in a, or16// the value zero if a is zero. The least significant bit is index one.17 18COMPILER_RT_ABI int __ffsdi2(di_int a) {19 dwords x;20 x.all = a;21 if (x.s.low == 0) {22 if (x.s.high == 0)23 return 0;24 return ctzsi(x.s.high) + (1 + sizeof(si_int) * CHAR_BIT);25 }26 return ctzsi(x.s.low) + 1;27}28