10b57cec5SDimitry Andric //===-- divmodsi4.c - Implement __divmodsi4 20b57cec5SDimitry Andric //--------------------------------===// 30b57cec5SDimitry Andric // 40b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 50b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 60b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 70b57cec5SDimitry Andric // 80b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 90b57cec5SDimitry Andric // 100b57cec5SDimitry Andric // This file implements __divmodsi4 for the compiler_rt library. 110b57cec5SDimitry Andric // 120b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 130b57cec5SDimitry Andric 140b57cec5SDimitry Andric #include "int_lib.h" 150b57cec5SDimitry Andric 160b57cec5SDimitry Andric // Returns: a / b, *rem = a % b 170b57cec5SDimitry Andric 180b57cec5SDimitry Andric COMPILER_RT_ABI si_int __divmodsi4(si_int a, si_int b, si_int *rem) { 19e8d8bef9SDimitry Andric const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1; 20e8d8bef9SDimitry Andric si_int s_a = a >> bits_in_word_m1; // s_a = a < 0 ? -1 : 0 21e8d8bef9SDimitry Andric si_int s_b = b >> bits_in_word_m1; // s_b = b < 0 ? -1 : 0 22*5f757f3fSDimitry Andric a = (su_int)(a ^ s_a) - s_a; // negate if s_a == -1 23*5f757f3fSDimitry Andric b = (su_int)(b ^ s_b) - s_b; // negate if s_b == -1 24e8d8bef9SDimitry Andric s_b ^= s_a; // sign of quotient 25e8d8bef9SDimitry Andric su_int r; 26e8d8bef9SDimitry Andric si_int q = (__udivmodsi4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -1 27e8d8bef9SDimitry Andric *rem = (r ^ s_a) - s_a; // negate if s_a == -1 28e8d8bef9SDimitry Andric return q; 290b57cec5SDimitry Andric } 30