1 //===-- Unittests for fabs ------------------------------------------------===//
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/fabs.h"
11 #include "utils/FPUtil/BitPatterns.h"
12 #include "utils/FPUtil/FloatOperations.h"
13 #include "utils/FPUtil/FloatProperties.h"
14 #include "utils/MPFRWrapper/MPFRUtils.h"
15 #include "utils/UnitTest/Test.h"
16 
17 using __llvm_libc::fputil::valueAsBits;
18 using __llvm_libc::fputil::valueFromBits;
19 
20 using BitPatterns = __llvm_libc::fputil::BitPatterns<double>;
21 using Properties = __llvm_libc::fputil::FloatProperties<double>;
22 
23 namespace mpfr = __llvm_libc::testing::mpfr;
24 
25 // Zero tolerance; As in, exact match with MPFR result.
26 static constexpr mpfr::Tolerance tolerance{mpfr::Tolerance::doublePrecision, 0,
27                                            0};
28 
29 TEST(FabsTest, SpecialNumbers) {
30   EXPECT_EQ(
31       BitPatterns::aQuietNaN,
32       valueAsBits(__llvm_libc::fabs(valueFromBits(BitPatterns::aQuietNaN))));
33   EXPECT_EQ(BitPatterns::aQuietNaN, valueAsBits(__llvm_libc::fabs(valueFromBits(
34                                         BitPatterns::aNegativeQuietNaN))));
35 
36   EXPECT_EQ(BitPatterns::aSignallingNaN,
37             valueAsBits(
38                 __llvm_libc::fabs(valueFromBits(BitPatterns::aSignallingNaN))));
39   EXPECT_EQ(BitPatterns::aSignallingNaN,
40             valueAsBits(__llvm_libc::fabs(
41                 valueFromBits(BitPatterns::aNegativeSignallingNaN))));
42 
43   EXPECT_EQ(BitPatterns::inf,
44             valueAsBits(__llvm_libc::fabs(valueFromBits(BitPatterns::inf))));
45   EXPECT_EQ(BitPatterns::inf,
46             valueAsBits(__llvm_libc::fabs(valueFromBits(BitPatterns::negInf))));
47 
48   EXPECT_EQ(BitPatterns::zero,
49             valueAsBits(__llvm_libc::fabs(valueFromBits(BitPatterns::zero))));
50   EXPECT_EQ(BitPatterns::zero, valueAsBits(__llvm_libc::fabs(
51                                    valueFromBits(BitPatterns::negZero))));
52 }
53 
54 TEST(FabsTest, InDoubleRange) {
55   using BitsType = Properties::BitsType;
56   constexpr BitsType count = 1000000;
57   constexpr BitsType step = UINT64_MAX / count;
58   for (BitsType i = 0, v = 0; i <= count; ++i, v += step) {
59     double x = valueFromBits(v);
60     if (isnan(x) || isinf(x))
61       continue;
62     ASSERT_MPFR_MATCH(mpfr::OP_Abs, x, __llvm_libc::fabs(x), tolerance);
63   }
64 }
65