libc/test/src/math/atanf_test.cpp

   1 //===-- Unittests for atanf -----------------------------------------------===//
   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 "src/__support/FPUtil/FPBits.h"
  10 #include "src/math/atanf.h"
  11 #include "test/UnitTest/FPMatcher.h"
  12 #include "test/UnitTest/Test.h"
  13 #include "utils/MPFRWrapper/MPFRUtils.h"
  14 #include <math.h>
  15
  16 #include <errno.h>
  17 #include <stdint.h>
  18
  19 #include <initializer_list>
  20
  21 using FPBits = __llvm_libc::fputil::FPBits<float>;
  22
  23 namespace mpfr = __llvm_libc::testing::mpfr;
  24
  25 DECLARE_SPECIAL_CONSTANTS(float)
  26
  27 TEST(LlvmLibcAtanfTest, SpecialNumbers) {
  28   errno = 0;
  29   __llvm_libc::fputil::clear_except(FE_ALL_EXCEPT);
  30   EXPECT_FP_EQ(aNaN, __llvm_libc::atanf(aNaN));
  31   EXPECT_FP_EXCEPTION(0);
  32   EXPECT_MATH_ERRNO(0);
  33
  34   __llvm_libc::fputil::clear_except(FE_ALL_EXCEPT);
  35   EXPECT_FP_EQ(0.0f, __llvm_libc::atanf(0.0f));
  36   EXPECT_FP_EXCEPTION(0);
  37   EXPECT_MATH_ERRNO(0);
  38
  39   __llvm_libc::fputil::clear_except(FE_ALL_EXCEPT);
  40   EXPECT_FP_EQ(-0.0f, __llvm_libc::atanf(-0.0f));
  41   EXPECT_FP_EXCEPTION(0);
  42   EXPECT_MATH_ERRNO(0);
  43 }
  44
  45 TEST(LlvmLibcAtanfTest, InFloatRange) {
  46   constexpr uint32_t COUNT = 1000000;
  47   const uint32_t STEP = FPBits(inf).uintval() / COUNT;
  48   for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
  49     float x = float(FPBits(v));
  50     EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan, x,
  51                                    __llvm_libc::atanf(x), 0.5);
  52     EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan, -x,
  53                                    __llvm_libc::atanf(-x), 0.5);
  54   }
  55 }
  56
  57 // For small values, tanh(x) is x.
  58 TEST(LlvmLibcAtanfTest, SpecialValues) {
  59   for (uint32_t v : {0x3d8d6b23U, 0x3feefcfbU, 0xbd8d6b23U, 0xbfeefcfbU,
  60                      0x7F800000U, 0xFF800000U}) {
  61     float x = float(FPBits(v));
  62     EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan, x,
  63                                    __llvm_libc::atanf(x), 0.5);
  64   }
  65 }