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//===-- divmodti4.c - Implement __divmodti4 -------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements __divmodti4 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
#ifdef CRT_HAS_128BIT
// Returns: a / b, *rem = a % b
COMPILER_RT_ABI ti_int __divmodti4(ti_int a, ti_int b, ti_int *rem) {
const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1;
ti_int s_a = a >> bits_in_tword_m1; // s_a = a < 0 ? -1 : 0
ti_int s_b = b >> bits_in_tword_m1; // s_b = b < 0 ? -1 : 0
a = (tu_int)(a ^ s_a) - s_a; // negate if s_a == -1
b = (tu_int)(b ^ s_b) - s_b; // negate if s_b == -1
s_b ^= s_a; // sign of quotient
tu_int r;
ti_int q = (__udivmodti4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -1
*rem = (r ^ s_a) - s_a; // negate if s_a == -1
return q;
}
#endif // CRT_HAS_128BIT
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