| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame^] | 1 | //===-- paritysi2.c - Implement __paritysi2 -------------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file implements __paritysi2 for the compiler_rt library. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
| 14 | #include "int_lib.h" |
| 15 | |
| 16 | // Returns: 1 if number of bits is odd else returns 0 |
| 17 | |
| 18 | si_int |
| 19 | __paritysi2(si_int a) |
| 20 | { |
| 21 | su_int x = (su_int)a; |
| 22 | x ^= x >> 16; |
| 23 | x ^= x >> 8; |
| 24 | x ^= x >> 4; |
| 25 | return (0x6996 >> (x & 0xF)) & 1; |
| 26 | } |