libc/test/src/fenv/enabled_exceptions_test.cpp

   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
  24 using LlvmLibcExceptionStatusTest = LIBC_NAMESPACE::testing::FEnvSafeTest;
  25
  26 // This test enables an exception and verifies that raising that exception
  27 // triggers SIGFPE.
  28 TEST_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(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 }