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1//===-- ashrti3.c - Implement __ashrti3 -----------------------------------===//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 __ashrti3 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15#ifdef CRT_HAS_128BIT16 17// Returns: arithmetic a >> b18 19// Precondition: 0 <= b < bits_in_tword20 21COMPILER_RT_ABI ti_int __ashrti3(ti_int a, int b) {22 const int bits_in_dword = (int)(sizeof(di_int) * CHAR_BIT);23 twords input;24 twords result;25 input.all = a;26 if (b & bits_in_dword) /* bits_in_dword <= b < bits_in_tword */ {27 // result.s.high = input.s.high < 0 ? -1 : 028 result.s.high = input.s.high >> (bits_in_dword - 1);29 result.s.low = input.s.high >> (b - bits_in_dword);30 } else /* 0 <= b < bits_in_dword */ {31 if (b == 0)32 return a;33 result.s.high = input.s.high >> b;34 result.s.low =35 ((du_int)input.s.high << (bits_in_dword - b)) | (input.s.low >> b);36 }37 return result.all;38}39 40#endif // CRT_HAS_128BIT41