libc/test/src/fenv/exception_flags_test.cpp

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