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1//===-- divmodsi4.c - Implement __divmodsi42//--------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9//10// This file implements __divmodsi4 for the compiler_rt library.11//12//===----------------------------------------------------------------------===//13 14#include "int_lib.h"15 16// Returns: a / b, *rem = a % b17 18COMPILER_RT_ABI si_int __divmodsi4(si_int a, si_int b, si_int *rem) {19 const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1;20 si_int s_a = a >> bits_in_word_m1; // s_a = a < 0 ? -1 : 021 si_int s_b = b >> bits_in_word_m1; // s_b = b < 0 ? -1 : 022 a = (su_int)(a ^ s_a) - s_a; // negate if s_a == -123 b = (su_int)(b ^ s_b) - s_b; // negate if s_b == -124 s_b ^= s_a; // sign of quotient25 su_int r;26 si_int q = (__udivmodsi4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -127 *rem = (r ^ s_a) - s_a; // negate if s_a == -128 return q;29}30