1 //===-- Unittests for feholdexcept 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/feholdexcept.h"
10
11 #include "src/__support/FPUtil/FEnvImpl.h"
12 #include "src/__support/architectures.h"
13 #include "utils/UnitTest/FPExceptMatcher.h"
14 #include "utils/UnitTest/Test.h"
15
16 #include <fenv.h>
17
TEST(LlvmLibcFEnvTest,RaiseAndCrash)18 TEST(LlvmLibcFEnvTest, RaiseAndCrash) {
19 #if defined(LLVM_LIBC_ARCH_AARCH64)
20 // Few aarch64 HW implementations do not trap exceptions. We skip this test
21 // completely on such HW.
22 //
23 // Whether HW supports trapping exceptions or not is deduced by enabling an
24 // exception and reading back to see if the exception got enabled. If the
25 // exception did not get enabled, then it means that the HW does not support
26 // trapping exceptions.
27 __llvm_libc::fputil::disable_except(FE_ALL_EXCEPT);
28 __llvm_libc::fputil::enable_except(FE_DIVBYZERO);
29 if (__llvm_libc::fputil::get_except() == 0)
30 return;
31 #endif // defined(LLVM_LIBC_ARCH_AARCH64)
32
33 int excepts[] = {FE_DIVBYZERO, FE_INVALID, FE_INEXACT, FE_OVERFLOW,
34 FE_UNDERFLOW};
35
36 for (int e : excepts) {
37 fenv_t env;
38 __llvm_libc::fputil::disable_except(FE_ALL_EXCEPT);
39 __llvm_libc::fputil::enable_except(e);
40 ASSERT_EQ(__llvm_libc::fputil::clear_except(FE_ALL_EXCEPT), 0);
41 ASSERT_EQ(__llvm_libc::feholdexcept(&env), 0);
42 // feholdexcept should disable all excepts so raising an exception
43 // should not crash/invoke the exception handler.
44 ASSERT_EQ(__llvm_libc::fputil::raise_except(e), 0);
45
46 ASSERT_RAISES_FP_EXCEPT([=] {
47 // When we put back the saved env, which has the exception enabled, it
48 // should crash with SIGFPE. Note that we set the old environment
49 // back inside this closure because in some test frameworks like Fuchsia's
50 // zxtest, this test translates to a death test in which this closure is
51 // run in a different thread. So, we set the old environment inside
52 // this closure so that the exception gets enabled for the thread running
53 // this closure.
54 __llvm_libc::fputil::set_env(&env);
55 __llvm_libc::fputil::raise_except(e);
56 });
57
58 // Cleanup
59 __llvm_libc::fputil::disable_except(FE_ALL_EXCEPT);
60 ASSERT_EQ(__llvm_libc::fputil::clear_except(FE_ALL_EXCEPT), 0);
61 }
62 }
63