1 | /* ===-- paritysi2.c - Implement __paritysi2 -------------------------------=== |
2 | * |
3 | * The LLVM Compiler Infrastructure |
4 | * |
5 | * This file is dual licensed under the MIT and the University of Illinois Open |
6 | * Source Licenses. See LICENSE.TXT for details. |
7 | * |
8 | * ===----------------------------------------------------------------------=== |
9 | * |
10 | * This file implements __paritysi2 for the compiler_rt library. |
11 | * |
12 | * ===----------------------------------------------------------------------=== |
13 | */ |
14 | |
15 | #include "int_lib.h" |
16 | |
17 | /* Returns: 1 if number of bits is odd else returns 0 */ |
18 | |
19 | COMPILER_RT_ABI si_int |
20 | __paritysi2(si_int a) |
21 | { |
22 | su_int x = (su_int)a; |
23 | x ^= x >> 16; |
24 | x ^= x >> 8; |
25 | x ^= x >> 4; |
26 | return (0x6996 >> (x & 0xF)) & 1; |
27 | } |
28 | |