127 lines · cpp
1//===-- Unittests for expf ------------------------------------------------===//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-exception6//7//===----------------------------------------------------------------------===//8 9#include "hdr/math_macros.h"10#include "hdr/stdint_proxy.h"11#include "src/__support/FPUtil/FPBits.h"12#include "src/__support/libc_errno.h"13#include "src/__support/macros/optimization.h"14#include "src/math/expf.h"15#include "test/UnitTest/FPMatcher.h"16#include "test/UnitTest/Test.h"17#include "utils/MPFRWrapper/MPFRUtils.h"18 19#ifdef LIBC_MATH_HAS_SKIP_ACCURATE_PASS20#define TOLERANCE 121#else22#define TOLERANCE 023#endif // LIBC_MATH_HAS_SKIP_ACCURATE_PASS24 25using LlvmLibcExpfTest = LIBC_NAMESPACE::testing::FPTest<float>;26 27namespace mpfr = LIBC_NAMESPACE::testing::mpfr;28 29TEST_F(LlvmLibcExpfTest, SpecialNumbers) {30 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::expf(aNaN));31 EXPECT_MATH_ERRNO(0);32 33 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::expf(inf));34 EXPECT_MATH_ERRNO(0);35 36 EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::expf(neg_inf));37 EXPECT_MATH_ERRNO(0);38 39 EXPECT_FP_EQ(1.0f, LIBC_NAMESPACE::expf(0.0f));40 EXPECT_MATH_ERRNO(0);41 42 EXPECT_FP_EQ(1.0f, LIBC_NAMESPACE::expf(-0.0f));43 EXPECT_MATH_ERRNO(0);44}45 46TEST_F(LlvmLibcExpfTest, Overflow) {47 EXPECT_FP_EQ_WITH_EXCEPTION(48 inf, LIBC_NAMESPACE::expf(FPBits(0x7f7fffffU).get_val()), FE_OVERFLOW);49 EXPECT_MATH_ERRNO(ERANGE);50 51 EXPECT_FP_EQ_WITH_EXCEPTION(52 inf, LIBC_NAMESPACE::expf(FPBits(0x42cffff8U).get_val()), FE_OVERFLOW);53 EXPECT_MATH_ERRNO(ERANGE);54 55 EXPECT_FP_EQ_WITH_EXCEPTION(56 inf, LIBC_NAMESPACE::expf(FPBits(0x42d00008U).get_val()), FE_OVERFLOW);57 EXPECT_MATH_ERRNO(ERANGE);58}59 60TEST_F(LlvmLibcExpfTest, Underflow) {61 EXPECT_FP_EQ_WITH_EXCEPTION(62 0.0f, LIBC_NAMESPACE::expf(FPBits(0xff7fffffU).get_val()), FE_UNDERFLOW);63 EXPECT_MATH_ERRNO(ERANGE);64 65 float x = FPBits(0xc2cffff8U).get_val();66 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,67 LIBC_NAMESPACE::expf(x), 0.5);68 EXPECT_MATH_ERRNO(ERANGE);69 70 x = FPBits(0xc2d00008U).get_val();71 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,72 LIBC_NAMESPACE::expf(x), 0.5);73 EXPECT_MATH_ERRNO(ERANGE);74}75 76// Test with inputs which are the borders of underflow/overflow but still77// produce valid results without setting errno.78TEST_F(LlvmLibcExpfTest, Borderline) {79 float x;80 81 x = FPBits(0x42affff8U).get_val();82 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,83 LIBC_NAMESPACE::expf(x), 0.5);84 EXPECT_MATH_ERRNO(0);85 86 x = FPBits(0x42b00008U).get_val();87 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,88 LIBC_NAMESPACE::expf(x), 0.5);89 EXPECT_MATH_ERRNO(0);90 91 x = FPBits(0xc2affff8U).get_val();92 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,93 LIBC_NAMESPACE::expf(x), 0.5);94 EXPECT_MATH_ERRNO(0);95 96 x = FPBits(0xc2b00008U).get_val();97 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,98 LIBC_NAMESPACE::expf(x), 0.5);99 EXPECT_MATH_ERRNO(0);100 101 x = FPBits(0xc236bd8cU).get_val();102 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,103 LIBC_NAMESPACE::expf(x), TOLERANCE + 0.5);104 EXPECT_MATH_ERRNO(0);105}106 107TEST_F(LlvmLibcExpfTest, InFloatRange) {108 constexpr uint32_t COUNT = 100'000;109 constexpr uint32_t STEP = UINT32_MAX / COUNT;110 for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {111 float x = FPBits(v).get_val();112 if (FPBits(v).is_nan() || FPBits(v).is_inf())113 continue;114 libc_errno = 0;115 float result = LIBC_NAMESPACE::expf(x);116 117 // If the computation resulted in an error or did not produce valid result118 // in the single-precision floating point range, then ignore comparing with119 // MPFR result as MPFR can still produce valid results because of its120 // wider precision.121 if (FPBits(result).is_nan() || FPBits(result).is_inf() || libc_errno != 0)122 continue;123 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp, x,124 LIBC_NAMESPACE::expf(x), 0.5);125 }126}127