libc/test/src/fenv/feholdexcept_test.cpp

   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 "hdr/types/fenv_t.h"
  10 #include "src/fenv/feholdexcept.h"
  11
  12 #include "src/__support/FPUtil/FEnvImpl.h"
  13 #include "src/__support/macros/properties/architectures.h"
  14 #include "test/UnitTest/FEnvSafeTest.h"
  15 #include "test/UnitTest/FPExceptMatcher.h"
  16 #include "test/UnitTest/Test.h"
  17
  18 #include "excepts.h"
  19
  20 using LlvmLibcFEnvTest = LIBC_NAMESPACE::testing::FEnvSafeTest;
  21
  22 TEST_F(LlvmLibcFEnvTest, RaiseAndCrash) {
  23 #if defined(LIBC_TARGET_ARCH_IS_ANY_ARM) ||                                    \
  24     defined(LIBC_TARGET_ARCH_IS_ANY_RISCV)
  25   // Few Arm HW implementations do not trap exceptions. We skip this test
  26   // completely on such HW.
  27   //
  28   // Whether HW supports trapping exceptions or not is deduced by enabling an
  29   // exception and reading back to see if the exception got enabled. If the
  30   // exception did not get enabled, then it means that the HW does not support
  31   // trapping exceptions.
  32   LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
  33   LIBC_NAMESPACE::fputil::enable_except(FE_DIVBYZERO);
  34   if (LIBC_NAMESPACE::fputil::get_except() == 0)
  35     return;
  36 #endif // Architectures where exception trapping is not supported
  37
  38   int excepts[] = {FE_DIVBYZERO, FE_INVALID, FE_INEXACT, FE_OVERFLOW,
  39                    FE_UNDERFLOW};
  40
  41   for (int e : excepts) {
  42     fenv_t env;
  43     LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
  44     LIBC_NAMESPACE::fputil::enable_except(e);
  45     ASSERT_EQ(LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT), 0);
  46     ASSERT_EQ(LIBC_NAMESPACE::feholdexcept(&env), 0);
  47     // feholdexcept should disable all excepts so raising an exception
  48     // should not crash/invoke the exception handler.
  49     ASSERT_EQ(LIBC_NAMESPACE::fputil::raise_except(e), 0);
  50
  51     ASSERT_RAISES_FP_EXCEPT([=] {
  52       // When we put back the saved env, which has the exception enabled, it
  53       // should crash with SIGFPE. Note that we set the old environment
  54       // back inside this closure because in some test frameworks like Fuchsia's
  55       // zxtest, this test translates to a death test in which this closure is
  56       // run in a different thread. So, we set the old environment inside
  57       // this closure so that the exception gets enabled for the thread running
  58       // this closure.
  59       LIBC_NAMESPACE::fputil::set_env(&env);
  60       LIBC_NAMESPACE::fputil::raise_except(e);
  61     });
  62
  63     // Cleanup
  64     LIBC_NAMESPACE::fputil::disable_except(FE_ALL_EXCEPT);
  65     ASSERT_EQ(LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT), 0);
  66   }
  67 }