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1//===-- divmodti4.c - Implement __divmodti4 -------------------------------===//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 __divmodti4 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15#ifdef CRT_HAS_128BIT16 17// Returns: a / b, *rem = a % b18 19COMPILER_RT_ABI ti_int __divmodti4(ti_int a, ti_int b, ti_int *rem) {20 const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1;21 ti_int s_a = a >> bits_in_tword_m1; // s_a = a < 0 ? -1 : 022 ti_int s_b = b >> bits_in_tword_m1; // s_b = b < 0 ? -1 : 023 a = (tu_int)(a ^ s_a) - s_a; // negate if s_a == -124 b = (tu_int)(b ^ s_b) - s_b; // negate if s_b == -125 s_b ^= s_a; // sign of quotient26 tu_int r;27 ti_int q = (__udivmodti4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -128 *rem = (r ^ s_a) - s_a; // negate if s_a == -129 return q;30}31 32#endif // CRT_HAS_128BIT33