llvm-project/compiler-rt/lib/builtins/parityti2.c

32 lines
888 B
C

//===-- parityti2.c - Implement __parityti2 -------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements __parityti2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
#ifdef CRT_HAS_128BIT
// Returns: 1 if number of bits is odd else returns 0
COMPILER_RT_ABI int __parityti2(ti_int a) {
twords x;
dwords x2;
x.all = a;
x2.all = x.s.high ^ x.s.low;
su_int x3 = x2.s.high ^ x2.s.low;
x3 ^= x3 >> 16;
x3 ^= x3 >> 8;
x3 ^= x3 >> 4;
return (0x6996 >> (x3 & 0xF)) & 1;
}
#endif // CRT_HAS_128BIT