blob: 8d720eb1df7425192fedf38121e86e199ca52e5f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
//===-- divsi3.c - Implement __divsi3 -------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __divsi3 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
su_int __udivsi3(su_int n, su_int d);
// Returns: a / b
si_int
__divsi3(si_int a, si_int b)
{
const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1;
si_int s_a = a >> bits_in_word_m1; // s_a = a < 0 ? -1 : 0
si_int s_b = b >> bits_in_word_m1; // s_b = b < 0 ? -1 : 0
a = (a ^ s_a) - s_a; // negate if s_a == -1
b = (b ^ s_b) - s_b; // negate if s_b == -1
s_a ^= s_b; // sign of quotient
return (__udivsi3(a, b) ^ s_a) - s_a; // negate if s_a == -1
}
|
