xref: /aosp_15_r20/external/compiler-rt/lib/builtins/paritysi2.c (revision 7c3d14c8b49c529e04be81a3ce6f5cc23712e4c6)
1*7c3d14c8STreehugger Robot /* ===-- paritysi2.c - Implement __paritysi2 -------------------------------===
2*7c3d14c8STreehugger Robot  *
3*7c3d14c8STreehugger Robot  *                     The LLVM Compiler Infrastructure
4*7c3d14c8STreehugger Robot  *
5*7c3d14c8STreehugger Robot  * This file is dual licensed under the MIT and the University of Illinois Open
6*7c3d14c8STreehugger Robot  * Source Licenses. See LICENSE.TXT for details.
7*7c3d14c8STreehugger Robot  *
8*7c3d14c8STreehugger Robot  * ===----------------------------------------------------------------------===
9*7c3d14c8STreehugger Robot  *
10*7c3d14c8STreehugger Robot  * This file implements __paritysi2 for the compiler_rt library.
11*7c3d14c8STreehugger Robot  *
12*7c3d14c8STreehugger Robot  * ===----------------------------------------------------------------------===
13*7c3d14c8STreehugger Robot  */
14*7c3d14c8STreehugger Robot 
15*7c3d14c8STreehugger Robot #include "int_lib.h"
16*7c3d14c8STreehugger Robot 
17*7c3d14c8STreehugger Robot /* Returns: 1 if number of bits is odd else returns 0 */
18*7c3d14c8STreehugger Robot 
19*7c3d14c8STreehugger Robot COMPILER_RT_ABI si_int
__paritysi2(si_int a)20*7c3d14c8STreehugger Robot __paritysi2(si_int a)
21*7c3d14c8STreehugger Robot {
22*7c3d14c8STreehugger Robot     su_int x = (su_int)a;
23*7c3d14c8STreehugger Robot     x ^= x >> 16;
24*7c3d14c8STreehugger Robot     x ^= x >> 8;
25*7c3d14c8STreehugger Robot     x ^= x >> 4;
26*7c3d14c8STreehugger Robot     return (0x6996 >> (x & 0xF)) & 1;
27*7c3d14c8STreehugger Robot }
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