1 //===-- Unittests for copysign --------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "include/math.h"
10 #include "src/math/copysign.h"
11 #include "utils/FPUtil/FPBits.h"
12 #include "utils/FPUtil/TestHelpers.h"
13 #include "utils/UnitTest/Test.h"
14 
15 using FPBits = __llvm_libc::fputil::FPBits<double>;
16 
17 static const double zero = FPBits::zero();
18 static const double negZero = FPBits::negZero();
19 static const double nan = FPBits::buildNaN(1);
20 static const double inf = FPBits::inf();
21 static const double negInf = FPBits::negInf();
22 
23 TEST(CopySignTest, SpecialNumbers) {
24   EXPECT_FP_EQ(nan, __llvm_libc::copysign(nan, -1.0));
25   EXPECT_FP_EQ(nan, __llvm_libc::copysign(nan, 1.0));
26 
27   EXPECT_FP_EQ(negInf, __llvm_libc::copysign(inf, -1.0));
28   EXPECT_FP_EQ(inf, __llvm_libc::copysign(negInf, 1.0));
29 
30   EXPECT_FP_EQ(negZero, __llvm_libc::copysign(zero, -1.0));
31   EXPECT_FP_EQ(zero, __llvm_libc::copysign(negZero, 1.0));
32 }
33 
34 TEST(CopySignTest, InDoubleRange) {
35   using UIntType = FPBits::UIntType;
36   constexpr UIntType count = 10000000;
37   constexpr UIntType step = UIntType(-1) / count;
38   for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
39     double x = FPBits(v);
40     if (isnan(x) || isinf(x) || x == 0)
41       continue;
42 
43     double res1 = __llvm_libc::copysign(x, -x);
44     ASSERT_FP_EQ(res1, -x);
45 
46     double res2 = __llvm_libc::copysign(x, x);
47     ASSERT_FP_EQ(res2, x);
48   }
49 }
50