ladybird/Tests/LibC/TestMath.cpp
kleines Filmröllchen 0c1ad05f50 LibC: Add rounding specializations for RISC-V
Whenever the floating-point values are in integer range, we can use the
various FCVT functions with static rounding mode to perform fast
rounding. I took this opportunity to clean up the architecture
differentiation for these functions, which allows us to use the software
rounding implementation for all extreme and unimplemented cases,
including AArch64.

Also adds more round & trunc tests.
2024-04-23 19:18:09 -06:00

342 lines
16 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Platform.h>
#if defined(AK_COMPILER_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(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)
{
// NOTE: We run tests for all three float types since architecture-specific code may vary significantly between types.
#define TEST_FLOOR_FOR(suffix) \
EXPECT_EQ(floor##suffix(0.125f), 0.f); \
EXPECT_EQ(floor##suffix(-0.125f), -1.0f); \
EXPECT_EQ(floor##suffix(0.5f), 0.f); \
EXPECT_EQ(floor##suffix(-0.5f), -1.0f); \
EXPECT_EQ(floor##suffix(0.25f), 0.f); \
EXPECT_EQ(floor##suffix(-0.25f), -1.0f); \
EXPECT_EQ(floor##suffix(-3.0f / 2.0f), -2.0f);
TEST_FLOOR_FOR();
TEST_FLOOR_FOR(f);
TEST_FLOOR_FOR(l);
EXPECT_EQ(floor(-9999999999999.5), -10000000000000.0);
EXPECT_EQ(floor(9999999999999.5), 9999999999999.0);
}
TEST_CASE(ceil)
{
#define TEST_CEIL_FOR(suffix) \
EXPECT_EQ(ceil##suffix(0.125##suffix), 1.0##suffix); \
EXPECT_EQ(ceil##suffix(-0.125##suffix), 0.##suffix); \
EXPECT_EQ(ceil##suffix(0.5##suffix), 1.0##suffix); \
EXPECT_EQ(ceil##suffix(-0.5##suffix), 0.##suffix); \
EXPECT_EQ(ceil##suffix(0.25##suffix), 1.0##suffix); \
EXPECT_EQ(ceil##suffix(-0.25##suffix), 0.##suffix); \
EXPECT_EQ(ceil##suffix(-3.0##suffix / 2.0##suffix), -1.0##suffix);
TEST_CEIL_FOR();
TEST_CEIL_FOR(f);
TEST_CEIL_FOR(l);
EXPECT_EQ(ceil(9999999999999.5), 10000000000000.0);
EXPECT_EQ(ceil(-9999999999999.5), -9999999999999.0);
}
TEST_CASE(trunc)
{
#define TEST_TRUNC_FOR(suffix) \
EXPECT_EQ(trunc##suffix(0.125##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(-0.125##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(0.5##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(-0.5##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(0.25##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(-0.25##suffix), 0.##suffix); \
EXPECT_EQ(trunc##suffix(-3.0##suffix / 2.0##suffix), -1.0##suffix);
TEST_TRUNC_FOR();
TEST_TRUNC_FOR(f);
TEST_TRUNC_FOR(l);
EXPECT_EQ(trunc(9999999999999.5), 9999999999999.0);
EXPECT_EQ(trunc(-9999999999999.5), -9999999999999.0);
}
TEST_CASE(round)
{
#define TEST_ROUND_FOR(suffix) \
EXPECT_EQ(round##suffix(0.125##suffix), 0.##suffix); \
EXPECT_EQ(round##suffix(-0.125##suffix), 0.##suffix); \
EXPECT_EQ(round##suffix(0.5##suffix), 1.0##suffix); \
EXPECT_EQ(round##suffix(-0.5##suffix), -1.0##suffix); \
EXPECT_EQ(round##suffix(0.25##suffix), 0.##suffix); \
EXPECT_EQ(round##suffix(-0.25##suffix), 0.##suffix); \
EXPECT_EQ(round##suffix(-3.0##suffix / 2.0##suffix), -2.0##suffix);
TEST_ROUND_FOR();
TEST_ROUND_FOR(f);
TEST_ROUND_FOR(l);
EXPECT_EQ(round(9999999999999.5), 10000000000000.0);
EXPECT_EQ(round(-9999999999999.5), -10000000000000.0);
}