1 //===-- Unittests for sqrtf -----------------------------------------------===//
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/sqrtf.h"
11 #include "utils/FPUtil/FPBits.h"
12 #include "utils/FPUtil/TestHelpers.h"
13 #include "utils/MPFRWrapper/MPFRUtils.h"
14 
15 using FPBits = __llvm_libc::fputil::FPBits<float>;
16 using UIntType = typename FPBits::UIntType;
17 
18 namespace mpfr = __llvm_libc::testing::mpfr;
19 
20 constexpr UIntType HiddenBit =
21     UIntType(1) << __llvm_libc::fputil::MantissaWidth<float>::value;
22 
23 float nan = FPBits::buildNaN(1);
24 float inf = FPBits::inf();
25 float negInf = FPBits::negInf();
26 
27 TEST(SqrtfTest, SpecialValues) {
28   ASSERT_FP_EQ(nan, __llvm_libc::sqrtf(nan));
29   ASSERT_FP_EQ(inf, __llvm_libc::sqrtf(inf));
30   ASSERT_FP_EQ(nan, __llvm_libc::sqrtf(negInf));
31   ASSERT_FP_EQ(0.0f, __llvm_libc::sqrtf(0.0f));
32   ASSERT_FP_EQ(-0.0f, __llvm_libc::sqrtf(-0.0f));
33   ASSERT_FP_EQ(nan, __llvm_libc::sqrtf(-1.0f));
34   ASSERT_FP_EQ(1.0f, __llvm_libc::sqrtf(1.0f));
35   ASSERT_FP_EQ(2.0f, __llvm_libc::sqrtf(4.0f));
36   ASSERT_FP_EQ(3.0f, __llvm_libc::sqrtf(9.0f));
37 }
38 
39 TEST(SqrtfTest, DenormalValues) {
40   for (UIntType mant = 1; mant < HiddenBit; mant <<= 1) {
41     FPBits denormal(0.0f);
42     denormal.mantissa = mant;
43 
44     ASSERT_MPFR_MATCH(mpfr::Operation::Sqrt, float(denormal),
45                       __llvm_libc::sqrtf(denormal), 0.5);
46   }
47 
48   constexpr UIntType count = 1'000'001;
49   constexpr UIntType step = HiddenBit / count;
50   for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
51     float x = *reinterpret_cast<float *>(&v);
52     ASSERT_MPFR_MATCH(mpfr::Operation::Sqrt, x, __llvm_libc::sqrtf(x), 0.5);
53   }
54 }
55 
56 TEST(SqrtfTest, InFloatRange) {
57   constexpr UIntType count = 10'000'001;
58   constexpr UIntType step = UIntType(-1) / count;
59   for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
60     float x = *reinterpret_cast<float *>(&v);
61     if (isnan(x) || (x < 0)) {
62       continue;
63     }
64 
65     ASSERT_MPFR_MATCH(mpfr::Operation::Sqrt, x, __llvm_libc::sqrtf(x), 0.5);
66   }
67 }
68