xref: /llvm-project/libc/test/src/fenv/exception_flags_test.cpp (revision 75bbf4dd7cfda744d4a2487cfd06a58194d02db3)
1 //===-- Unittests for fegetexceptflag and fesetexceptflag -----------------===//
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/types/fexcept_t.h"
10 #include "src/fenv/fegetexceptflag.h"
11 #include "src/fenv/fesetexceptflag.h"
12 
13 #include "src/__support/FPUtil/FEnvImpl.h"
14 #include "test/UnitTest/Test.h"
15 
16 TEST(LlvmLibcFenvTest, GetExceptFlagAndSetExceptFlag) {
17   // We will disable all exceptions to prevent invocation of the exception
18   // handler.
19   LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
20   LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
21 
22   int excepts[] = {FE_DIVBYZERO, FE_INVALID, FE_INEXACT, FE_OVERFLOW,
23                    FE_UNDERFLOW};
24 
25   for (int e : excepts) {
26     // The overall idea is to raise an except and save the exception flags.
27     // Next, clear the flags and then set the saved exception flags. This
28     // should set the flag corresponding to the previously raised exception.
29     LIBC_NAMESPACE::fputil::raise_except(e);
30     // Make sure that the exception flag is set.
31     ASSERT_NE(LIBC_NAMESPACE::fputil::test_except(FE_ALL_EXCEPT) & e, 0);
32 
33     fexcept_t eflags;
34     ASSERT_EQ(LIBC_NAMESPACE::fegetexceptflag(&eflags, FE_ALL_EXCEPT), 0);
35 
36     LIBC_NAMESPACE::fputil::clear_except(e);
37     ASSERT_EQ(LIBC_NAMESPACE::fputil::test_except(FE_ALL_EXCEPT) & e, 0);
38 
39     ASSERT_EQ(LIBC_NAMESPACE::fesetexceptflag(&eflags, FE_ALL_EXCEPT), 0);
40     ASSERT_NE(LIBC_NAMESPACE::fputil::test_except(FE_ALL_EXCEPT) & e, 0);
41 
42     // Cleanup. We clear all excepts as raising excepts like FE_OVERFLOW
43     // can also raise FE_INEXACT.
44     LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
45   }
46 
47   // Next, we will raise one exception and save the flags.
48   LIBC_NAMESPACE::fputil::raise_except(FE_INVALID);
49   fexcept_t eflags;
50   LIBC_NAMESPACE::fegetexceptflag(&eflags, FE_ALL_EXCEPT);
51   // Clear all exceptions and raise two other exceptions.
52   LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
53   LIBC_NAMESPACE::fputil::raise_except(FE_OVERFLOW | FE_INEXACT);
54   // When we set the flags and test, we should only see FE_INVALID.
55   LIBC_NAMESPACE::fesetexceptflag(&eflags, FE_ALL_EXCEPT);
56   EXPECT_EQ(LIBC_NAMESPACE::fputil::test_except(FE_ALL_EXCEPT), FE_INVALID);
57 }
58