xref: /rk3399_ARM-atf/lib/compiler-rt/builtins/divmoddi4.c (revision 8a6a9560b5dcccfb68064c0c8c9b4b47981c6ac7)
1*8a6a9560SDaniel Boulby //===-- divmoddi4.c - Implement __divmoddi4 -------------------------------===//
2*8a6a9560SDaniel Boulby //
3*8a6a9560SDaniel Boulby // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*8a6a9560SDaniel Boulby // See https://llvm.org/LICENSE.txt for license information.
5*8a6a9560SDaniel Boulby // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*8a6a9560SDaniel Boulby //
7*8a6a9560SDaniel Boulby //===----------------------------------------------------------------------===//
8*8a6a9560SDaniel Boulby //
9*8a6a9560SDaniel Boulby // This file implements __divmoddi4 for the compiler_rt library.
10*8a6a9560SDaniel Boulby //
11*8a6a9560SDaniel Boulby //===----------------------------------------------------------------------===//
128c80c865SLionel Debieve 
138c80c865SLionel Debieve #include "int_lib.h"
148c80c865SLionel Debieve 
15*8a6a9560SDaniel Boulby // Returns: a / b, *rem = a % b
168c80c865SLionel Debieve 
17*8a6a9560SDaniel Boulby COMPILER_RT_ABI di_int __divmoddi4(di_int a, di_int b, di_int *rem) {
18*8a6a9560SDaniel Boulby   const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;
19*8a6a9560SDaniel Boulby   di_int s_a = a >> bits_in_dword_m1;                   // s_a = a < 0 ? -1 : 0
20*8a6a9560SDaniel Boulby   di_int s_b = b >> bits_in_dword_m1;                   // s_b = b < 0 ? -1 : 0
21*8a6a9560SDaniel Boulby   a = (a ^ s_a) - s_a;                                  // negate if s_a == -1
22*8a6a9560SDaniel Boulby   b = (b ^ s_b) - s_b;                                  // negate if s_b == -1
23*8a6a9560SDaniel Boulby   s_b ^= s_a;                                           // sign of quotient
24*8a6a9560SDaniel Boulby   du_int r;
25*8a6a9560SDaniel Boulby   di_int q = (__udivmoddi4(a, b, &r) ^ s_b) - s_b;      // negate if s_b == -1
26*8a6a9560SDaniel Boulby   *rem = (r ^ s_a) - s_a;                               // negate if s_a == -1
27*8a6a9560SDaniel Boulby   return q;
288c80c865SLionel Debieve }
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