1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <gtest/gtest.h>
18
19#include <fenv.h>
20#include <stdint.h>
21
22static void TestRounding(float expectation1, float expectation2) {
23  // volatile to prevent compiler optimizations.
24  volatile float f = 1.968750f;
25  volatile float m = 0x1.0p23f;
26  volatile float x = f + m;
27  ASSERT_FLOAT_EQ(expectation1, x);
28  x -= m;
29  ASSERT_EQ(expectation2, x);
30}
31
32static void DivideByZero() {
33  // volatile to prevent compiler optimizations.
34  volatile float zero = 0.0f;
35  volatile float result __attribute__((unused)) = 123.0f / zero;
36}
37
38TEST(fenv, fesetround_fegetround_FE_TONEAREST) {
39  fesetround(FE_TONEAREST);
40  ASSERT_EQ(FE_TONEAREST, fegetround());
41  TestRounding(8388610.0f, 2.0f);
42}
43
44TEST(fenv, fesetround_fegetround_FE_TOWARDZERO) {
45  fesetround(FE_TOWARDZERO);
46  ASSERT_EQ(FE_TOWARDZERO, fegetround());
47  TestRounding(8388609.0f, 1.0f);
48}
49
50TEST(fenv, fesetround_fegetround_FE_UPWARD) {
51  fesetround(FE_UPWARD);
52  ASSERT_EQ(FE_UPWARD, fegetround());
53  TestRounding(8388610.0f, 2.0f);
54}
55
56TEST(fenv, fesetround_fegetround_FE_DOWNWARD) {
57  fesetround(FE_DOWNWARD);
58  ASSERT_EQ(FE_DOWNWARD, fegetround());
59  TestRounding(8388609.0f, 1.0f);
60}
61
62TEST(fenv, feclearexcept_fetestexcept) {
63  // Clearing clears.
64  feclearexcept(FE_ALL_EXCEPT);
65  ASSERT_EQ(0, fetestexcept(FE_ALL_EXCEPT));
66
67  // Dividing by zero sets FE_DIVBYZERO.
68  DivideByZero();
69  int raised = fetestexcept(FE_DIVBYZERO | FE_OVERFLOW);
70  ASSERT_TRUE((raised & FE_OVERFLOW) == 0);
71  ASSERT_TRUE((raised & FE_DIVBYZERO) != 0);
72
73  // Clearing an unset bit is a no-op.
74  feclearexcept(FE_OVERFLOW);
75  ASSERT_TRUE((raised & FE_OVERFLOW) == 0);
76  ASSERT_TRUE((raised & FE_DIVBYZERO) != 0);
77
78  // Clearing a set bit works.
79  feclearexcept(FE_DIVBYZERO);
80  ASSERT_EQ(0, fetestexcept(FE_ALL_EXCEPT));
81}
82
83TEST(fenv, FE_DFL_ENV_macro) {
84  ASSERT_EQ(0, fesetenv(FE_DFL_ENV));
85}
86