29 lines · c
1//===-- divmoddi4.c - Implement __divmoddi4 -------------------------------===//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 __divmoddi4 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15// Returns: a / b, *rem = a % b16 17COMPILER_RT_ABI di_int __divmoddi4(di_int a, di_int b, di_int *rem) {18 const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;19 di_int s_a = a >> bits_in_dword_m1; // s_a = a < 0 ? -1 : 020 di_int s_b = b >> bits_in_dword_m1; // s_b = b < 0 ? -1 : 021 a = (du_int)(a ^ s_a) - s_a; // negate if s_a == -122 b = (du_int)(b ^ s_b) - s_b; // negate if s_b == -123 s_b ^= s_a; // sign of quotient24 du_int r;25 di_int q = (__udivmoddi4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -126 *rem = (r ^ s_a) - s_a; // negate if s_a == -127 return q;28}29