libc/test/src/math/tanpif16_test.cpp

//===-- Exhaustive test for tanpif16 --------------------------------------===//
//
// 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/macros/optimization.h"
#include "src/math/tanpif16.h"
#include "test/UnitTest/FPMatcher.h"
#include "test/UnitTest/Test.h"
#include "utils/MPFRWrapper/MPFRUtils.h"

#ifdef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
#define TOLERANCE 1
#else
#define TOLERANCE 0
#endif // LIBC_MATH_HAS_SKIP_ACCURATE_PASS

using LlvmLibcTanpif16Test = LIBC_NAMESPACE::testing::FPTest<float16>;

namespace mpfr = LIBC_NAMESPACE::testing::mpfr;

// Range: [0, Inf]
static constexpr uint16_t POS_START = 0x0000U;
static constexpr uint16_t POS_STOP = 0x7c00U;

// Range: [-Inf, 0]
static constexpr uint16_t NEG_START = 0x8000U;
static constexpr uint16_t NEG_STOP = 0xfc00U;

TEST_F(LlvmLibcTanpif16Test, PositiveRange) {
  for (uint16_t v = POS_START; v <= POS_STOP; ++v) {
    float16 x = FPBits(v).get_val();
    EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Tanpi, x,
                                   LIBC_NAMESPACE::tanpif16(x),
                                   TOLERANCE + 0.5);
  }
}

TEST_F(LlvmLibcTanpif16Test, NegativeRange) {
  for (uint16_t v = NEG_START; v <= NEG_STOP; ++v) {
    float16 x = FPBits(v).get_val();
    EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Tanpi, x,
                                   LIBC_NAMESPACE::tanpif16(x),
                                   TOLERANCE + 0.5);
  }
}

TEST_F(LlvmLibcTanpif16Test, IntegerSigns) {
  // The MPFR matcher does not distinguish the signs of zeros.
  constexpr struct {
    float16 input, expected;
  } ZERO_TESTS[] = {{1.0f16, neg_zero},
                    {2.0f16, zero},
                    {0x1.004p10f16, neg_zero}, // 2^10 + 1 is odd.
                    {0x1.004p11f16, zero}};    // 2^11 + 2 is even.
  for (const auto &test : ZERO_TESTS) {
    EXPECT_FP_EQ_ALL_ROUNDING(test.expected,
                              LIBC_NAMESPACE::tanpif16(test.input));
    EXPECT_FP_EQ_ALL_ROUNDING(-test.expected,
                              LIBC_NAMESPACE::tanpif16(-test.input));
  }
}