1//===-- Unittests for feraiseexcept with exceptions enabled ---------------===//
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/fenv/feclearexcept.h"
10#include "src/fenv/feraiseexcept.h"
11#include "src/fenv/fetestexcept.h"
12
13#include "src/__support/FPUtil/FEnvImpl.h"
14#include "src/__support/macros/properties/architectures.h"
15#include "test/UnitTest/FEnvSafeTest.h"
16#include "test/UnitTest/FPExceptMatcher.h"
17#include "test/UnitTest/Test.h"
18
19#include "hdr/fenv_macros.h"
20#include <signal.h>
21
22#include "excepts.h"
23
24using LlvmLibcExceptionStatusTest = LIBC_NAMESPACE::testing::FEnvSafeTest;
25
26// This test enables an exception and verifies that raising that exception
27// triggers SIGFPE.
28TEST_F(LlvmLibcExceptionStatusTest, RaiseAndCrash) {
29#if defined(LIBC_TARGET_ARCH_IS_ANY_ARM) || \
30 defined(LIBC_TARGET_ARCH_IS_ANY_RISCV)
31 // Few Arm HW implementations do not trap exceptions. We skip this test
32 // completely on such HW.
33 //
34 // Whether HW supports trapping exceptions or not is deduced by enabling an
35 // exception and reading back to see if the exception got enabled. If the
36 // exception did not get enabled, then it means that the HW does not support
37 // trapping exceptions.
38 LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
39 LIBC_NAMESPACE::fputil::enable_except(FE_DIVBYZERO);
40 if (LIBC_NAMESPACE::fputil::get_except() == 0)
41 return;
42#endif // Architectures where exception trapping is not supported
43
44 // TODO: Install a floating point exception handler and verify that the
45 // the expected exception was raised. One will have to longjmp back from
46 // that exception handler, so such a testing can be done after we have
47 // longjmp implemented.
48
49 for (int e : EXCEPTS) {
50 LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
51 LIBC_NAMESPACE::fputil::enable_except(excepts: e);
52 ASSERT_EQ(LIBC_NAMESPACE::feclearexcept(FE_ALL_EXCEPT), 0);
53 // Raising all exceptions except |e| should not call the
54 // SIGFPE handler. They should set the exception flag though,
55 // so we verify that. Since other exceptions like FE_DIVBYZERO
56 // can raise FE_INEXACT as well, we don't verify the other
57 // exception flags when FE_INEXACT is enabled.
58 if (e != FE_INEXACT) {
59 int others = ALL_EXCEPTS & ~e;
60 ASSERT_EQ(LIBC_NAMESPACE::feraiseexcept(others), 0);
61 ASSERT_EQ(LIBC_NAMESPACE::fetestexcept(others), others);
62 }
63
64 ASSERT_RAISES_FP_EXCEPT([=] {
65 // In test frameworks like Fuchsia's zxtest, this translates to
66 // a death test which runs this closure in a different thread. So,
67 // we enable the exception again inside this closure so that the
68 // exception gets enabled for the thread running this closure.
69 LIBC_NAMESPACE::fputil::enable_except(e);
70 LIBC_NAMESPACE::feraiseexcept(e);
71 });
72
73 // Cleanup.
74 LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
75 ASSERT_EQ(LIBC_NAMESPACE::feclearexcept(FE_ALL_EXCEPT), 0);
76 }
77}
78

source code of libc/test/src/fenv/enabled_exceptions_test.cpp