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1//===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------===//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 __ashrdi3 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15// Returns: arithmetic a >> b16 17// Precondition: 0 <= b < bits_in_dword18 19COMPILER_RT_ABI di_int __ashrdi3(di_int a, int b) {20 const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);21 dwords input;22 dwords result;23 input.all = a;24 if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ {25 // result.s.high = input.s.high < 0 ? -1 : 026 result.s.high = input.s.high >> (bits_in_word - 1);27 result.s.low = input.s.high >> (b - bits_in_word);28 } else /* 0 <= b < bits_in_word */ {29 if (b == 0)30 return a;31 result.s.high = input.s.high >> b;32 result.s.low =33 ((su_int)input.s.high << (bits_in_word - b)) | (input.s.low >> b);34 }35 return result.all;36}37 38#if defined(__ARM_EABI__)39COMPILER_RT_ALIAS(__ashrdi3, __aeabi_lasr)40#endif41