libc/test/src/math/LogbTest.h

   1 //===-- Utility class to test logb[f|l] -------------------------*- C++ -*-===//
   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 "src/__support/FPUtil/ManipulationFunctions.h"
  10 #include "test/UnitTest/FEnvSafeTest.h"
  11 #include "test/UnitTest/FPMatcher.h"
  12 #include "test/UnitTest/Test.h"
  13 #include "utils/MPFRWrapper/MPFRUtils.h"
  14
  15 #include "hdr/math_macros.h"
  16
  17 namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
  18
  19 template <typename T>
  20 class LogbTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
  21
  22   DECLARE_SPECIAL_CONSTANTS(T)
  23
  24   static constexpr StorageType HIDDEN_BIT =
  25       StorageType(1) << LIBC_NAMESPACE::fputil::FPBits<T>::FRACTION_LEN;
  26
  27 public:
  28   typedef T (*LogbFunc)(T);
  29
  30   void testSpecialNumbers(LogbFunc func) {
  31     ASSERT_FP_EQ(aNaN, func(aNaN));
  32     ASSERT_FP_EQ(inf, func(inf));
  33     ASSERT_FP_EQ(inf, func(neg_inf));
  34     ASSERT_FP_EQ(neg_inf, func(0.0));
  35     ASSERT_FP_EQ(neg_inf, func(-0.0));
  36   }
  37
  38   void testPowersOfTwo(LogbFunc func) {
  39     EXPECT_FP_EQ(T(0.0), func(T(1.0)));
  40     EXPECT_FP_EQ(T(0.0), func(T(-1.0)));
  41
  42     EXPECT_FP_EQ(T(1.0), func(T(2.0)));
  43     EXPECT_FP_EQ(T(1.0), func(T(-2.0)));
  44
  45     EXPECT_FP_EQ(T(2.0), func(T(4.0)));
  46     EXPECT_FP_EQ(T(2.0), func(T(-4.0)));
  47
  48     EXPECT_FP_EQ(T(3.0), func(T(8.0)));
  49     EXPECT_FP_EQ(T(3.0), func(T(-8.0)));
  50
  51     EXPECT_FP_EQ(T(4.0), func(T(16.0)));
  52     EXPECT_FP_EQ(T(4.0), func(T(-16.0)));
  53
  54     EXPECT_FP_EQ(T(5.0), func(T(32.0)));
  55     EXPECT_FP_EQ(T(5.0), func(T(-32.0)));
  56   }
  57
  58   void testSomeIntegers(LogbFunc func) {
  59     EXPECT_FP_EQ(T(1.0), func(T(3.0)));
  60     EXPECT_FP_EQ(T(1.0), func(T(-3.0)));
  61
  62     EXPECT_FP_EQ(T(2.0), func(T(7.0)));
  63     EXPECT_FP_EQ(T(2.0), func(T(-7.0)));
  64
  65     EXPECT_FP_EQ(T(3.0), func(T(10.0)));
  66     EXPECT_FP_EQ(T(3.0), func(T(-10.0)));
  67
  68     EXPECT_FP_EQ(T(4.0), func(T(31.0)));
  69     EXPECT_FP_EQ(T(4.0), func(T(-31.0)));
  70
  71     EXPECT_FP_EQ(T(5.0), func(T(55.0)));
  72     EXPECT_FP_EQ(T(5.0), func(T(-55.0)));
  73   }
  74
  75   void testRange(LogbFunc func) {
  76     using StorageType = typename FPBits::StorageType;
  77     constexpr StorageType COUNT = 100'000;
  78     constexpr StorageType STEP = STORAGE_MAX / COUNT;
  79     for (StorageType i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
  80       T x = FPBits(v).get_val();
  81       if (FPBits(v).is_nan() || FPBits(v).is_inf() || x == 0.0l)
  82         continue;
  83
  84       int exponent;
  85       LIBC_NAMESPACE::fputil::frexp(x, exponent);
  86       ASSERT_FP_EQ(T(exponent), func(x) + T(1.0));
  87     }
  88   }
  89 };
  90
  91 #define LIST_LOGB_TESTS(T, func)                                               \
  92   using LlvmLibcLogbTest = LogbTest<T>;                                        \
  93   TEST_F(LlvmLibcLogbTest, SpecialNumbers) { testSpecialNumbers(&func); }      \
  94   TEST_F(LlvmLibcLogbTest, PowersOfTwo) { testPowersOfTwo(&func); }            \
  95   TEST_F(LlvmLibcLogbTest, SomeIntegers) { testSomeIntegers(&func); }          \
  96   TEST_F(LlvmLibcLogbTest, InRange) { testRange(&func); }