1*0b57cec5SDimitry Andric //===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------===// 2*0b57cec5SDimitry Andric // 3*0b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*0b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5*0b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*0b57cec5SDimitry Andric // 7*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 8*0b57cec5SDimitry Andric // 9*0b57cec5SDimitry Andric // This file implements __ashrdi3 for the compiler_rt library. 10*0b57cec5SDimitry Andric // 11*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 12*0b57cec5SDimitry Andric 13*0b57cec5SDimitry Andric #include "int_lib.h" 14*0b57cec5SDimitry Andric 15*0b57cec5SDimitry Andric // Returns: arithmetic a >> b 16*0b57cec5SDimitry Andric 17*0b57cec5SDimitry Andric // Precondition: 0 <= b < bits_in_dword 18*0b57cec5SDimitry Andric 19*0b57cec5SDimitry Andric COMPILER_RT_ABI di_int __ashrdi3(di_int a, si_int b) { 20*0b57cec5SDimitry Andric const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT); 21*0b57cec5SDimitry Andric dwords input; 22*0b57cec5SDimitry Andric dwords result; 23*0b57cec5SDimitry Andric input.all = a; 24*0b57cec5SDimitry Andric if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ { 25*0b57cec5SDimitry Andric // result.s.high = input.s.high < 0 ? -1 : 0 26*0b57cec5SDimitry Andric result.s.high = input.s.high >> (bits_in_word - 1); 27*0b57cec5SDimitry Andric result.s.low = input.s.high >> (b - bits_in_word); 28*0b57cec5SDimitry Andric } else /* 0 <= b < bits_in_word */ { 29*0b57cec5SDimitry Andric if (b == 0) 30*0b57cec5SDimitry Andric return a; 31*0b57cec5SDimitry Andric result.s.high = input.s.high >> b; 32*0b57cec5SDimitry Andric result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b); 33*0b57cec5SDimitry Andric } 34*0b57cec5SDimitry Andric return result.all; 35*0b57cec5SDimitry Andric } 36*0b57cec5SDimitry Andric 37*0b57cec5SDimitry Andric #if defined(__ARM_EABI__) 38*0b57cec5SDimitry Andric COMPILER_RT_ALIAS(__ashrdi3, __aeabi_lasr) 39*0b57cec5SDimitry Andric #endif 40