xref: /llvm-project/libc/test/src/math/trunc_test.cpp (revision ed8982da3e3122ffe2de8801d6ca1e1bd1e3c10a)
1 //===-- Unittests for trunc -----------------------------------------------===//
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/trunc.h"
11 #include "utils/FPUtil/FPBits.h"
12 #include "utils/FPUtil/TestHelpers.h"
13 #include "utils/MPFRWrapper/MPFRUtils.h"
14 #include "utils/UnitTest/Test.h"
15 
16 using FPBits = __llvm_libc::fputil::FPBits<double>;
17 
18 namespace mpfr = __llvm_libc::testing::mpfr;
19 
20 static const double zero = FPBits::zero();
21 static const double negZero = FPBits::negZero();
22 static const double nan = FPBits::buildNaN(1);
23 static const double inf = FPBits::inf();
24 static const double negInf = FPBits::negInf();
25 
26 TEST(TruncTest, SpecialNumbers) {
27   EXPECT_FP_EQ(zero, __llvm_libc::trunc(zero));
28   EXPECT_FP_EQ(negZero, __llvm_libc::trunc(negZero));
29 
30   EXPECT_FP_EQ(inf, __llvm_libc::trunc(inf));
31   EXPECT_FP_EQ(negInf, __llvm_libc::trunc(negInf));
32 
33   ASSERT_NE(isnan(nan), 0);
34   ASSERT_NE(isnan(__llvm_libc::trunc(nan)), 0);
35 }
36 
37 TEST(TruncTest, RoundedNumbers) {
38   EXPECT_FP_EQ(1.0, __llvm_libc::trunc(1.0));
39   EXPECT_FP_EQ(-1.0, __llvm_libc::trunc(-1.0));
40   EXPECT_FP_EQ(10.0, __llvm_libc::trunc(10.0));
41   EXPECT_FP_EQ(-10.0, __llvm_libc::trunc(-10.0));
42   EXPECT_FP_EQ(1234.0, __llvm_libc::trunc(1234.0));
43   EXPECT_FP_EQ(-1234.0, __llvm_libc::trunc(-1234.0));
44 }
45 
46 TEST(TruncTest, Fractions) {
47   EXPECT_FP_EQ(0.0, __llvm_libc::trunc(0.5));
48   EXPECT_FP_EQ(-0.0, __llvm_libc::trunc(-0.5));
49   EXPECT_FP_EQ(0.0, __llvm_libc::trunc(0.115));
50   EXPECT_FP_EQ(-0.0, __llvm_libc::trunc(-0.115));
51   EXPECT_FP_EQ(0.0, __llvm_libc::trunc(0.715));
52   EXPECT_FP_EQ(-0.0, __llvm_libc::trunc(-0.715));
53   EXPECT_FP_EQ(1.0, __llvm_libc::trunc(1.3));
54   EXPECT_FP_EQ(-1.0, __llvm_libc::trunc(-1.3));
55   EXPECT_FP_EQ(1.0, __llvm_libc::trunc(1.5));
56   EXPECT_FP_EQ(-1.0, __llvm_libc::trunc(-1.5));
57   EXPECT_FP_EQ(1.0, __llvm_libc::trunc(1.75));
58   EXPECT_FP_EQ(-1.0, __llvm_libc::trunc(-1.75));
59   EXPECT_FP_EQ(10.0, __llvm_libc::trunc(10.32));
60   EXPECT_FP_EQ(-10.0, __llvm_libc::trunc(-10.32));
61   EXPECT_FP_EQ(10.0, __llvm_libc::trunc(10.65));
62   EXPECT_FP_EQ(-10.0, __llvm_libc::trunc(-10.65));
63   EXPECT_FP_EQ(1234.0, __llvm_libc::trunc(1234.38));
64   EXPECT_FP_EQ(-1234.0, __llvm_libc::trunc(-1234.38));
65   EXPECT_FP_EQ(1234.0, __llvm_libc::trunc(1234.96));
66   EXPECT_FP_EQ(-1234.0, __llvm_libc::trunc(-1234.96));
67 }
68 
69 TEST(TruncTest, InDoubleRange) {
70   using UIntType = FPBits::UIntType;
71   constexpr UIntType count = 10000000;
72   constexpr UIntType step = UIntType(-1) / count;
73   for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
74     double x = FPBits(v);
75     if (isnan(x) || isinf(x))
76       continue;
77 
78     ASSERT_MPFR_MATCH(mpfr::Operation::Trunc, x, __llvm_libc::trunc(x), 0.0);
79   }
80 }
81