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1//===-- lshrdi3.c - Implement __lshrdi3 -----------------------------------===//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 __lshrdi3 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15// Returns: logical a >> b16 17// Precondition: 0 <= b < bits_in_dword18 19COMPILER_RT_ABI di_int __lshrdi3(di_int a, int b) {20 const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);21 udwords input;22 udwords result;23 input.all = a;24 if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ {25 result.s.high = 0;26 result.s.low = input.s.high >> (b - bits_in_word);27 } else /* 0 <= b < bits_in_word */ {28 if (b == 0)29 return a;30 result.s.high = input.s.high >> b;31 result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b);32 }33 return result.all;34}35 36#if defined(__ARM_EABI__)37COMPILER_RT_ALIAS(__lshrdi3, __aeabi_llsr)38#endif39