compiler-rt/test/builtins/Unit/paritysi2_test.c

   1 // RUN: %clang_builtins %s %librt -o %t && %run %t
   2 // REQUIRES: librt_has_paritysi2
   3 //===-- paritysi2_test.c - Test __paritysi2 -------------------------------===//
   4 //
   5 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   6 // See https://llvm.org/LICENSE.txt for license information.
   7 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   8 //
   9 //===----------------------------------------------------------------------===//
  10 //
  11 // This file tests __paritysi2 for the compiler_rt library.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "int_lib.h"
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18
  19 // Returns: 1 if number of bits is odd else returns 0
  20
  21 COMPILER_RT_ABI si_int __paritysi2(si_int a);
  22
  23 int naive_parity(si_int a)
  24 {
  25     int r = 0;
  26     for (; a; a = a & (a - 1))
  27         r = ~r;
  28     return r & 1;
  29 }
  30
  31 int test__paritysi2(si_int a)
  32 {
  33     si_int x = __paritysi2(a);
  34     si_int expected = naive_parity(a);
  35     if (x != expected)
  36         printf("error in __paritysi2(0x%X) = %d, expected %d\n",
  37                a, x, expected);
  38     return x != expected;
  39 }
  40
  41 char assumption_2[sizeof(si_int)*CHAR_BIT == 32] = {0};
  42
  43 int main()
  44 {
  45     int i;
  46     for (i = 0; i < 10000; ++i)
  47         if (test__paritysi2(rand()))
  48             return 1;
  49
  50    return 0;
  51 }