| //===-- Unittests for log2 ------------------------------------------------===// |
| // |
| // 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 "src/__support/FPUtil/FPBits.h" |
| #include "src/errno/libc_errno.h" |
| #include "src/math/log2.h" |
| #include "test/UnitTest/FPMatcher.h" |
| #include "test/UnitTest/Test.h" |
| #include "utils/MPFRWrapper/MPFRUtils.h" |
| #include <math.h> |
| |
| #include <errno.h> |
| #include <stdint.h> |
| |
| namespace mpfr = __llvm_libc::testing::mpfr; |
| using __llvm_libc::testing::tlog; |
| |
| DECLARE_SPECIAL_CONSTANTS(double) |
| |
| TEST(LlvmLibcLog2Test, SpecialNumbers) { |
| EXPECT_FP_EQ(aNaN, __llvm_libc::log2(aNaN)); |
| EXPECT_FP_EQ(inf, __llvm_libc::log2(inf)); |
| EXPECT_FP_IS_NAN_WITH_EXCEPTION(__llvm_libc::log2(neg_inf), FE_INVALID); |
| EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, __llvm_libc::log2(0.0), FE_DIVBYZERO); |
| EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, __llvm_libc::log2(-0.0), FE_DIVBYZERO); |
| EXPECT_FP_IS_NAN_WITH_EXCEPTION(__llvm_libc::log2(-1.0), FE_INVALID); |
| EXPECT_FP_EQ_ALL_ROUNDING(zero, __llvm_libc::log2(1.0)); |
| } |
| |
| TEST(LlvmLibcLog2Test, TrickyInputs) { |
| constexpr int N = 30; |
| constexpr uint64_t INPUTS[N] = { |
| 0x3ff0000000000000, // x = 1.0 |
| 0x4024000000000000, // x = 10.0 |
| 0x4059000000000000, // x = 10^2 |
| 0x408f400000000000, // x = 10^3 |
| 0x40c3880000000000, // x = 10^4 |
| 0x40f86a0000000000, // x = 10^5 |
| 0x412e848000000000, // x = 10^6 |
| 0x416312d000000000, // x = 10^7 |
| 0x4197d78400000000, // x = 10^8 |
| 0x41cdcd6500000000, // x = 10^9 |
| 0x4202a05f20000000, // x = 10^10 |
| 0x42374876e8000000, // x = 10^11 |
| 0x426d1a94a2000000, // x = 10^12 |
| 0x42a2309ce5400000, // x = 10^13 |
| 0x42d6bcc41e900000, // x = 10^14 |
| 0x430c6bf526340000, // x = 10^15 |
| 0x4341c37937e08000, // x = 10^16 |
| 0x4376345785d8a000, // x = 10^17 |
| 0x43abc16d674ec800, // x = 10^18 |
| 0x43e158e460913d00, // x = 10^19 |
| 0x4415af1d78b58c40, // x = 10^20 |
| 0x444b1ae4d6e2ef50, // x = 10^21 |
| 0x4480f0cf064dd592, // x = 10^22 |
| 0x3fefffffffef06ad, 0x3fefde0f22c7d0eb, 0x225e7812faadb32f, |
| 0x3fee1076964c2903, 0x3fdfe93fff7fceb0, 0x3ff012631ad8df10, |
| 0x3fefbfdaa448ed98, |
| }; |
| for (int i = 0; i < N; ++i) { |
| double x = double(FPBits(INPUTS[i])); |
| EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log2, x, |
| __llvm_libc::log2(x), 0.5); |
| } |
| } |
| |
| TEST(LlvmLibcLog2Test, AllExponents) { |
| double x = 0x1.0p-1074; |
| for (int i = -1074; i < 1024; ++i, x *= 2.0) { |
| ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log2, x, |
| __llvm_libc::log2(x), 0.5); |
| } |
| } |
| |
| TEST(LlvmLibcLog2Test, InDoubleRange) { |
| constexpr uint64_t COUNT = 1'001; |
| constexpr uint64_t START = 0x3FD0'0000'0000'0000ULL; // 0.25 |
| constexpr uint64_t STOP = 0x4010'0000'0000'0000ULL; // 4.0 |
| // constexpr uint64_t START = 0x3FF0'0000'0000'0000ULL; // 1.0 |
| // constexpr uint64_t STOP = 0x4000'0000'0000'0000ULL; // 2.0 |
| constexpr uint64_t STEP = (STOP - START) / COUNT; |
| |
| auto test = [&](mpfr::RoundingMode rounding_mode) { |
| mpfr::ForceRoundingMode __r(rounding_mode); |
| 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 (isnan(x) || isinf(x) || x < 0.0) |
| continue; |
| libc_errno = 0; |
| double result = __llvm_libc::log2(x); |
| ++cc; |
| if (isnan(result) || isinf(result)) |
| continue; |
| |
| ++count; |
| // ASSERT_MPFR_MATCH(mpfr::Operation::Log2, x, result, 0.5); |
| if (!EXPECT_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Log2, x, result, |
| 0.5, rounding_mode)) { |
| ++fails; |
| while (!EXPECT_MPFR_MATCH_ROUNDING_SILENTLY( |
| mpfr::Operation::Log2, x, result, tol, rounding_mode)) { |
| mx = x; |
| mr = result; |
| tol *= 2.0; |
| } |
| } |
| } |
| tlog << " Log2 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::Log2, 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); |
| } |