Tests: Move the former LibM test into the LibC namespace

2 files changed, 293 insertions, 0 deletions

diff --git a/Tests/LibC/CMakeLists.txt b/Tests/LibC/CMakeLists.txt
index 28c27e9892..b82b612158 100644
--- a/Tests/LibC/CMakeLists.txt
+++ b/Tests/LibC/CMakeLists.txt
@@ -11,6 +11,7 @@ set(TEST_SOURCES
     TestLibCString.cpp
     TestLibCTime.cpp
     TestMalloc.cpp
+    TestMath.cpp
     TestMemalign.cpp
     TestMemmem.cpp
     TestMkDir.cpp
@@ -32,6 +33,7 @@ set(TEST_SOURCES
     TestWctype.cpp
 )
 
+set_source_files_properties(TestMath.cpp PROPERTIES COMPILE_FLAGS "-fno-builtin")
 set_source_files_properties(TestStrtodAccuracy.cpp PROPERTIES COMPILE_FLAGS "-fno-builtin-strtod")
 
 foreach(source IN LISTS TEST_SOURCES)
diff --git a/Tests/LibC/TestMath.cpp b/Tests/LibC/TestMath.cpp
new file mode 100644
index 0000000000..6898cbc7d0
--- /dev/null
+++ b/Tests/LibC/TestMath.cpp
@@ -0,0 +1,291 @@
+/*
+ * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#ifdef __clang__
+#    pragma clang optimize off
+#else
+#    pragma GCC optimize("O0")
+#endif
+
+#include <LibTest/TestCase.h>
+
+#include <float.h>
+#include <math.h>
+
+TEST_CASE(atan2)
+{
+    EXPECT_APPROXIMATE(atan2(-1, -0.0e0), -M_PI_2);
+    EXPECT_APPROXIMATE(atan2(-0.0e0, -1), -M_PI);
+    EXPECT_APPROXIMATE(atan2(0.0e0, -1), M_PI);
+    EXPECT_APPROXIMATE(atan2(-0.0e0, 1), -0.0e0);
+    EXPECT_APPROXIMATE(atan2(0.0e0, 1), 0.0e0);
+}
+
+TEST_CASE(trig)
+{
+    EXPECT_APPROXIMATE(sin(1234), 0.601928);
+    EXPECT_APPROXIMATE(cos(1234), -0.798551);
+    EXPECT_APPROXIMATE(tan(1234), -0.753775);
+    EXPECT_APPROXIMATE(sqrt(1234), 35.128336);
+    EXPECT_APPROXIMATE(sin(-1), -0.8414709848078965);
+    EXPECT_APPROXIMATE(cos(-1), 0.5403023058681398);
+    EXPECT_APPROXIMATE(tan(-1), -1.5574077246549023);
+    EXPECT(isnan(sqrt(-1)));
+    EXPECT(isnan(asin(1.1)));
+    EXPECT(isnan(asin(-1.1)));
+    EXPECT_APPROXIMATE(asin(0), 0.0);
+    EXPECT_APPROXIMATE(asin(0.01), 0.01);
+    EXPECT_APPROXIMATE(asin(0.1), 0.100167);
+    EXPECT_APPROXIMATE(asin(0.3), 0.304693);
+    EXPECT_APPROXIMATE(asin(0.499), 0.522444);
+    EXPECT_APPROXIMATE(asin(0.5), 0.523599);
+    EXPECT_APPROXIMATE(asin(0.501), 0.524754);
+    EXPECT_APPROXIMATE(asin(0.9), 1.119770);
+    EXPECT_APPROXIMATE(asin(0.99), 1.429257);
+    EXPECT_APPROXIMATE(asin(1.0), 1.570796);
+    EXPECT_APPROXIMATE(atan(0), 0.0);
+    EXPECT_APPROXIMATE(atan(0.5), 0.463648);
+    EXPECT_APPROXIMATE(atan(-0.5), -0.463648);
+    EXPECT_APPROXIMATE(atan(5.5), 1.390943);
+    EXPECT_APPROXIMATE(atan(-5.5), -1.390943);
+    EXPECT_APPROXIMATE(atan(555.5), 1.568996);
+}
+
+TEST_CASE(other)
+{
+    EXPECT_EQ(trunc(9999999999999.5), 9999999999999.0);
+    EXPECT_EQ(trunc(-9999999999999.5), -9999999999999.0);
+}
+
+TEST_CASE(exponents)
+{
+    struct values {
+        double x;
+        double exp;
+        double sinh;
+        double cosh;
+        double tanh;
+    };
+
+    values values[8] {
+        { 1.500000, 4.481689, 2.129279, 2.352410, 0.905148 },
+        { 20.990000, 1305693298.670892, 652846649.335446, 652846649.335446, 1.000000 },
+        { 20.010000, 490041186.687082, 245020593.343541, 245020593.343541, 1.000000 },
+        { 0.000000, 1.000000, 0.000000, 1.000000, 0.000000 },
+        { 0.010000, 1.010050, 0.010000, 1.000050, 0.010000 },
+        { -0.010000, 0.990050, -0.010000, 1.000050, -0.010000 },
+        { -1.000000, 0.367879, -1.175201, 1.543081, -0.761594 },
+        { -17.000000, 0.000000, -12077476.376788, 12077476.376788, -1.000000 },
+    };
+    for (auto& v : values) {
+        EXPECT_APPROXIMATE(exp(v.x), v.exp);
+        EXPECT_APPROXIMATE(sinh(v.x), v.sinh);
+        EXPECT_APPROXIMATE(cosh(v.x), v.cosh);
+        EXPECT_APPROXIMATE(tanh(v.x), v.tanh);
+    }
+    EXPECT_EQ(exp(1000), __builtin_huge_val());
+}
+
+TEST_CASE(logarithms)
+{
+    EXPECT(isnan(log(-1)));
+    EXPECT(log(0) < -1000000);
+    EXPECT_APPROXIMATE(log(0.5), -0.693147);
+    EXPECT_APPROXIMATE(log(1.1), 0.095310);
+    EXPECT_APPROXIMATE(log(5), 1.609438);
+    EXPECT_APPROXIMATE(log(5.5), 1.704748);
+    EXPECT_APPROXIMATE(log(500), 6.214608);
+    EXPECT_APPROXIMATE(log2(5), 2.321928);
+    EXPECT_APPROXIMATE(log10(5), 0.698970);
+}
+
+union Extractor {
+    explicit Extractor(double d)
+        : d(d)
+    {
+    }
+    Extractor(unsigned sign, unsigned exponent, unsigned long long mantissa)
+        : mantissa(mantissa)
+        , exponent(exponent)
+        , sign(sign)
+    {
+    }
+    struct {
+        unsigned long long mantissa : 52;
+        unsigned exponent : 11;
+        unsigned sign : 1;
+    };
+    double d;
+
+    bool operator==(Extractor const& other) const
+    {
+        return other.sign == sign && other.exponent == exponent && other.mantissa == mantissa;
+    }
+};
+namespace AK {
+template<>
+struct Formatter<Extractor> : StandardFormatter {
+    ErrorOr<void> format(FormatBuilder& builder, Extractor const& value)
+    {
+        TRY(builder.put_literal("{"sv));
+        TRY(builder.put_u64(value.sign));
+        TRY(builder.put_literal(", "sv));
+        TRY(builder.put_u64(value.exponent, 16, true));
+        TRY(builder.put_literal(", "sv));
+        TRY(builder.put_u64(value.mantissa, 16, true));
+        TRY(builder.put_literal("}"sv));
+        return {};
+    }
+};
+}
+
+static Extractor nextafter_translator(Extractor x, Extractor target)
+{
+    return Extractor(nextafter(x.d, target.d));
+}
+
+TEST_CASE(nextafter)
+{
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x1, 0x0), Extractor(0x0, 0x412, 0xe848000000000)), Extractor(0x0, 0x1, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x3ff, 0x0), Extractor(0x0, 0x412, 0xe848200000000)), Extractor(0x0, 0x3ff, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x0), Extractor(0x0, 0x412, 0xe848000000000)), Extractor(0x0, 0x0, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x0), Extractor(0x0, 0x412, 0xe848000000000)), Extractor(0x0, 0x0, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x3ff, 0x0), Extractor(0x0, 0x412, 0xe847e00000000)), Extractor(0x1, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x1), Extractor(0x0, 0x412, 0xe848000000000)), Extractor(0x0, 0x0, 0x2));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe848000000000), Extractor(0x0, 0x1, 0x0)), Extractor(0x0, 0x412, 0xe847fffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe848200000000), Extractor(0x0, 0x3ff, 0x0)), Extractor(0x0, 0x412, 0xe8481ffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe848000000000), Extractor(0x1, 0x0, 0x0)), Extractor(0x0, 0x412, 0xe847fffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe848000000000), Extractor(0x0, 0x0, 0x0)), Extractor(0x0, 0x412, 0xe847fffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe847e00000000), Extractor(0x1, 0x3ff, 0x0)), Extractor(0x0, 0x412, 0xe847dffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x412, 0xe848000000000), Extractor(0x0, 0x0, 0x1)), Extractor(0x0, 0x412, 0xe847fffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x1, 0x0), Extractor(0x0, 0x1, 0x0)), Extractor(0x0, 0x1, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x3ff, 0x0), Extractor(0x0, 0x3ff, 0x0)), Extractor(0x0, 0x3ff, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x0), Extractor(0x1, 0x0, 0x0)), Extractor(0x1, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x0), Extractor(0x0, 0x0, 0x0)), Extractor(0x0, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x3ff, 0x0), Extractor(0x1, 0x3ff, 0x0)), Extractor(0x1, 0x3ff, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x1), Extractor(0x0, 0x0, 0x1)), Extractor(0x0, 0x0, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x1, 0x7fe, 0xffffffffffffe));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x1, 0x0), Extractor(0x0, 0x1, 0x0)), Extractor(0x1, 0x0, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x3ff, 0x0), Extractor(0x0, 0x3ff, 0x0)), Extractor(0x1, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x0), Extractor(0x1, 0x0, 0x0)), Extractor(0x1, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x0), Extractor(0x0, 0x0, 0x0)), Extractor(0x0, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x3ff, 0x0), Extractor(0x1, 0x3ff, 0x0)), Extractor(0x0, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x1), Extractor(0x0, 0x0, 0x1)), Extractor(0x1, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x1, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xffffffffffffe));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x1, 0x0), Extractor(0x1, 0x1, 0x0)), Extractor(0x0, 0x0, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x3ff, 0x0), Extractor(0x1, 0x3ff, 0x0)), Extractor(0x0, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x0), Extractor(0x0, 0x0, 0x0)), Extractor(0x0, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x0), Extractor(0x1, 0x0, 0x0)), Extractor(0x1, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x3ff, 0x0), Extractor(0x0, 0x3ff, 0x0)), Extractor(0x1, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x1), Extractor(0x1, 0x0, 0x1)), Extractor(0x0, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x1, 0x0), Extractor(0x1, 0x419, 0x7d78400000000)), Extractor(0x0, 0x0, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x3ff, 0x0), Extractor(0x1, 0x419, 0x7d783fc000000)), Extractor(0x0, 0x3fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x0, 0x0), Extractor(0x1, 0x419, 0x7d78400000000)), Extractor(0x1, 0x0, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x0), Extractor(0x1, 0x419, 0x7d78400000000)), Extractor(0x1, 0x0, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x3ff, 0x0), Extractor(0x1, 0x419, 0x7d78404000000)), Extractor(0x1, 0x3ff, 0x1));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x0, 0x1), Extractor(0x1, 0x419, 0x7d78400000000)), Extractor(0x0, 0x0, 0x0));
+    EXPECT_EQ(nextafter_translator(Extractor(0x0, 0x7fe, 0xfffffffffffff), Extractor(0x0, 0x7fe, 0xfffffffffffff)), Extractor(0x0, 0x7fe, 0xfffffffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d78400000000), Extractor(0x0, 0x1, 0x0)), Extractor(0x1, 0x419, 0x7d783ffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d783fc000000), Extractor(0x0, 0x3ff, 0x0)), Extractor(0x1, 0x419, 0x7d783fbffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d78400000000), Extractor(0x1, 0x0, 0x0)), Extractor(0x1, 0x419, 0x7d783ffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d78400000000), Extractor(0x0, 0x0, 0x0)), Extractor(0x1, 0x419, 0x7d783ffffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d78404000000), Extractor(0x1, 0x3ff, 0x0)), Extractor(0x1, 0x419, 0x7d78403ffffff));
+    EXPECT_EQ(nextafter_translator(Extractor(0x1, 0x419, 0x7d78400000000), Extractor(0x0, 0x0, 0x1)), Extractor(0x1, 0x419, 0x7d783ffffffff));
+}
+
+TEST_CASE(scalbn)
+{
+    EXPECT(isnan(scalbn(NAN, 3)));
+    EXPECT(!isfinite(scalbn(INFINITY, 5)));
+    EXPECT_EQ(scalbn(0, 3), 0);
+    EXPECT_EQ(scalbn(15.3, 0), 15.3);
+
+    // TODO: implement denormal handling in fallback scalbn
+    //     EXPECT_EQ(scalbn(0x0.0000000000008p-1022, 16), 0x0.0000000000008p-1006);
+    static constexpr auto biggest_subnormal = DBL_MIN - DBL_TRUE_MIN;
+    auto smallest_normal = scalbn(biggest_subnormal, 1);
+    Extractor ex(smallest_normal);
+    EXPECT(ex.exponent != 0);
+
+    EXPECT_EQ(scalbn(2.0, 4), 32.0);
+}
+
+TEST_CASE(gamma)
+{
+    EXPECT(isinf(tgamma(+0.0)) && !signbit(tgamma(+0.0)));
+    EXPECT(isinf(tgamma(-0.0)) && signbit(tgamma(-0.0)));
+    EXPECT(isinf(tgamma(INFINITY)) && !signbit(tgamma(INFINITY)));
+    EXPECT(isnan(tgamma(NAN)));
+    EXPECT(isnan(tgamma(-INFINITY)));
+    EXPECT(isnan(tgamma(-5)));
+
+    // TODO: investigate Stirling approximation implementation of gamma function
+    // EXPECT_APPROXIMATE(tgamma(0.5), sqrt(M_PI));
+    EXPECT_EQ(tgammal(21.0l), 2'432'902'008'176'640'000.0l);
+    EXPECT_EQ(tgamma(19.0), 6'402'373'705'728'000.0);
+    EXPECT_EQ(tgammaf(11.0f), 3628800.0f);
+    EXPECT_EQ(tgamma(4.0), 6);
+
+    EXPECT_EQ(lgamma(1.0), 0.0);
+    EXPECT_EQ(lgamma(2.0), 0.0);
+    EXPECT(isinf(lgamma(0.0)));
+    EXPECT(!signbit(lgamma(-0.0)));
+    EXPECT(isnan(lgamma(NAN)));
+    EXPECT(isinf(lgamma(INFINITY)));
+    EXPECT(isinf(lgamma(-INFINITY)));
+    EXPECT_EQ(signgam, 1);
+    lgamma(-2.5);
+    EXPECT_EQ(signgam, -1);
+}
+
+TEST_CASE(fmax_and_fmin)
+{
+    EXPECT(fmax(-INFINITY, 0) == 0);
+    EXPECT(fmax(NAN, 12) == 12);
+    EXPECT(fmax(5, NAN) == 5);
+    EXPECT(isnan(fmax(NAN, NAN)));
+    EXPECT(isinf(fmax(1'000'000, INFINITY)));
+
+    EXPECT(isinf(fmin(-INFINITY, 0)));
+    EXPECT(fmin(0, INFINITY) == 0);
+    EXPECT(fmin(NAN, 5) == 5);
+    EXPECT(fmin(0, NAN) == 0);
+    EXPECT(isnan(fmin(NAN, NAN)));
+}
+
+TEST_CASE(acos)
+{
+    EXPECT_APPROXIMATE(acos(-1), M_PI);
+    EXPECT_APPROXIMATE(acos(0), 0.5 * M_PI);
+    EXPECT_APPROXIMATE(acos(1), 0);
+    EXPECT(isnan(acos(1.1)));
+}
+
+TEST_CASE(floor)
+{
+    EXPECT_EQ(floor(0.125), 0);
+    EXPECT_EQ(floor(-0.125), -1.0);
+    EXPECT_EQ(floor(0.5), 0);
+    EXPECT_EQ(floor(-0.5), -1.0);
+    EXPECT_EQ(floor(0.25), 0);
+    EXPECT_EQ(floor(-0.25), -1.0);
+    EXPECT_EQ(floor(-3.0 / 2.0), -2.0);
+}
+
+TEST_CASE(ceil)
+{
+    EXPECT_EQ(ceil(0.125), 1.0);
+    EXPECT_EQ(ceil(-0.125), 0);
+    EXPECT_EQ(ceil(0.5), 1.0);
+    EXPECT_EQ(ceil(-0.5), 0);
+    EXPECT_EQ(ceil(0.25), 1.0);
+    EXPECT_EQ(ceil(-0.25), 0);
+    EXPECT_EQ(ceil(-3.0 / 2.0), -1.0);
+}