//===-- Unittests for 2^x -------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "hdr/math_macros.h"
#include "src/__support/FPUtil/FPBits.h"
#include "src/errno/libc_errno.h"
#include "src/math/exp2.h"
#include "test/UnitTest/FPMatcher.h"
#include "test/UnitTest/Test.h"
#include "utils/MPFRWrapper/MPFRUtils.h"
#include <errno.h>
#include <stdint.h>
using LlvmLibcExp2Test = LIBC_NAMESPACE::testing::FPTest<double>;
namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
using LIBC_NAMESPACE::testing::tlog;
TEST_F(LlvmLibcExp2Test, SpecialNumbers) {
EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::exp2(aNaN));
EXPECT_FP_EQ(inf, LIBC_NAMESPACE::exp2(inf));
EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::exp2(neg_inf));
EXPECT_FP_EQ_WITH_EXCEPTION(zero, LIBC_NAMESPACE::exp2(-0x1.0p20),
FE_UNDERFLOW);
EXPECT_FP_EQ_WITH_EXCEPTION(inf, LIBC_NAMESPACE::exp2(0x1.0p20), FE_OVERFLOW);
EXPECT_FP_EQ_ALL_ROUNDING(1.0, LIBC_NAMESPACE::exp2(0.0));
EXPECT_FP_EQ_ALL_ROUNDING(1.0, LIBC_NAMESPACE::exp2(-0.0));
}
TEST_F(LlvmLibcExp2Test, TrickyInputs) {
constexpr int N = 16;
constexpr uint64_t INPUTS[N] = {
0x3FD79289C6E6A5C0,
0x3FD05DE80A173EA0, // 0x1.05de80a173eap-2
0xbf1eb7a4cb841fcc, // -0x1.eb7a4cb841fccp-14
0xbf19a61fb925970d,
0x3fda7b764e2cf47a, // 0x1.a7b764e2cf47ap-2
0xc04757852a4b93aa, // -0x1.757852a4b93aap+5
0x4044c19e5712e377, // x=0x1.4c19e5712e377p+5
0xbf19a61fb925970d, // x=-0x1.9a61fb925970dp-14
0xc039a74cdab36c28, // x=-0x1.9a74cdab36c28p+4
0xc085b3e4e2e3bba9, // x=-0x1.5b3e4e2e3bba9p+9
0xc086960d591aec34, // x=-0x1.6960d591aec34p+9
0xc086232c09d58d91, // x=-0x1.6232c09d58d91p+9
0xc0874910d52d3051, // x=-0x1.74910d52d3051p9
0xc0867a172ceb0990, // x=-0x1.67a172ceb099p+9
0xc08ff80000000000, // x=-0x1.ff8p+9
0xbc971547652b82fe, // x=-0x1.71547652b82fep-54
};
for (int i = 0; i < N; ++i) {
double x = FPBits(INPUTS[i]).get_val();
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
LIBC_NAMESPACE::exp2(x), 0.5);
}
}
TEST_F(LlvmLibcExp2Test, InDoubleRange) {
constexpr uint64_t COUNT = 1'231;
uint64_t START = LIBC_NAMESPACE::fputil::FPBits<double>(0.25).uintval();
uint64_t STOP = LIBC_NAMESPACE::fputil::FPBits<double>(4.0).uintval();
uint64_t STEP = (STOP - START) / COUNT;
auto test = [&](mpfr::RoundingMode rounding_mode) {
mpfr::ForceRoundingMode __r(rounding_mode);
if (!__r.success)
return;
uint64_t fails = 0;
uint64_t count = 0;
uint64_t cc = 0;
double mx, mr = 0.0;
double tol = 0.5;
for (uint64_t i = 0, v = START; i <= COUNT; ++i, v += STEP) {
double x = FPBits(v).get_val();
if (FPBits(v).is_nan() || FPBits(v).is_inf() || x < 0.0)
continue;
LIBC_NAMESPACE::libc_errno = 0;
double result = LIBC_NAMESPACE::exp2(x);
++cc;
if (FPBits(result).is_nan() || FPBits(result).is_inf())
continue;
++count;
if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Exp2, x, result,
0.5, rounding_mode)) {
++fails;
while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Exp2, x,
result, tol, rounding_mode)) {
mx = x;
mr = result;
if (tol > 1000.0)
break;
tol *= 2.0;
}
}
}
tlog << " Exp2 failed: " << fails << "/" << count << "/" << cc
<< " tests.\n";
tlog << " Max ULPs is at most: " << static_cast<uint64_t>(tol) << ".\n";
if (fails) {
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, mx, mr, 0.5, rounding_mode);
}
};
tlog << " Test Rounding To Nearest...\n";
test(mpfr::RoundingMode::Nearest);
tlog << " Test Rounding Downward...\n";
test(mpfr::RoundingMode::Downward);
tlog << " Test Rounding Upward...\n";
test(mpfr::RoundingMode::Upward);
tlog << " Test Rounding Toward Zero...\n";
test(mpfr::RoundingMode::TowardZero);
}