1 //===-- Unittests for log2f -----------------------------------------------===// 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 "hdr/math_macros.h" 10 #include "src/__support/FPUtil/FPBits.h" 11 #include "src/errno/libc_errno.h" 12 #include "src/math/log2f.h" 13 #include "test/UnitTest/FPMatcher.h" 14 #include "test/UnitTest/Test.h" 15 #include "utils/MPFRWrapper/MPFRUtils.h" 16 17 #include <stdint.h> 18 19 using LlvmLibcLog2fTest = LIBC_NAMESPACE::testing::FPTest<float>; 20 21 namespace mpfr = LIBC_NAMESPACE::testing::mpfr; 22 23 TEST_F(LlvmLibcLog2fTest, SpecialNumbers) { 24 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::log2f(aNaN)); 25 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::log2f(inf)); 26 EXPECT_FP_IS_NAN_WITH_EXCEPTION(LIBC_NAMESPACE::log2f(neg_inf), FE_INVALID); 27 EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, LIBC_NAMESPACE::log2f(0.0f), 28 FE_DIVBYZERO); 29 EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, LIBC_NAMESPACE::log2f(-0.0f), 30 FE_DIVBYZERO); 31 EXPECT_FP_IS_NAN_WITH_EXCEPTION(LIBC_NAMESPACE::log2f(-1.0f), FE_INVALID); 32 EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::log2f(1.0f)); 33 } 34 35 TEST_F(LlvmLibcLog2fTest, TrickyInputs) { 36 constexpr int N = 10; 37 constexpr uint32_t INPUTS[N] = { 38 0x3f7d57f5U, 0x3f7e3274U, 0x3f7ed848U, 0x3f7fd6ccU, 0x3f7fffffU, 39 0x3f80079bU, 0x3f81d0b5U, 0x3f82e602U, 0x3f83c98dU, 0x3f8cba39U}; 40 41 for (int i = 0; i < N; ++i) { 42 float x = FPBits(INPUTS[i]).get_val(); 43 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log2, x, 44 LIBC_NAMESPACE::log2f(x), 0.5); 45 } 46 } 47 48 TEST_F(LlvmLibcLog2fTest, InFloatRange) { 49 constexpr uint32_t COUNT = 100'000; 50 constexpr uint32_t STEP = UINT32_MAX / COUNT; 51 for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) { 52 float x = FPBits(v).get_val(); 53 if (FPBits(v).is_nan() || FPBits(v).is_inf()) 54 continue; 55 LIBC_NAMESPACE::libc_errno = 0; 56 float result = LIBC_NAMESPACE::log2f(x); 57 // If the computation resulted in an error or did not produce valid result 58 // in the single-precision floating point range, then ignore comparing with 59 // MPFR result as MPFR can still produce valid results because of its 60 // wider precision. 61 if (FPBits(result).is_nan() || FPBits(result).is_inf() || 62 LIBC_NAMESPACE::libc_errno != 0) 63 continue; 64 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log2, x, 65 LIBC_NAMESPACE::log2f(x), 0.5); 66 } 67 } 68