libc/test/UnitTest/FPExceptMatcher.cpp

   1 //===-- FPExceptMatchers.cpp ----------------------------------------------===//
   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 "FPExceptMatcher.h"
  10
  11 #include <fenv.h>
  12 #include <memory>
  13 #include <setjmp.h>
  14 #include <signal.h>
  15
  16 namespace LIBC_NAMESPACE {
  17 namespace testing {
  18
  19 #if defined(_WIN32)
  20 #define sigjmp_buf jmp_buf
  21 #define sigsetjmp(buf, save) setjmp(buf)
  22 #define siglongjmp(buf, val) longjmp(buf, val)
  23 #endif
  24
  25 static thread_local sigjmp_buf jumpBuffer;
  26 static thread_local bool caughtExcept;
  27
  28 static void sigfpeHandler(int sig) {
  29   caughtExcept = true;
  30   siglongjmp(jumpBuffer, -1);
  31 }
  32
  33 FPExceptMatcher::FPExceptMatcher(FunctionCaller *func) {
  34   auto oldSIGFPEHandler = signal(SIGFPE, &sigfpeHandler);
  35   std::unique_ptr<FunctionCaller> funcUP(func);
  36
  37   caughtExcept = false;
  38   fenv_t oldEnv;
  39   fegetenv(&oldEnv);
  40   if (sigsetjmp(jumpBuffer, 1) == 0)
  41     funcUP->call();
  42   // We restore the previous floating point environment after
  43   // the call to the function which can potentially raise SIGFPE.
  44   fesetenv(&oldEnv);
  45   signal(SIGFPE, oldSIGFPEHandler);
  46   exceptionRaised = caughtExcept;
  47 }
  48
  49 } // namespace testing
  50 } // namespace LIBC_NAMESPACE