libc/test/src/setjmp/setjmp_test.cpp

   1 //===-- Unittests for setjmp and longjmp ----------------------------------===//
   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/setjmp/longjmp.h"
  10 #include "src/setjmp/setjmp_impl.h"
  11 #include "test/UnitTest/Test.h"
  12
  13 jmp_buf buf;
  14 constexpr int MAX_LOOP = 123;
  15
  16 void jump_back(int n) {
  17   __llvm_libc::longjmp(buf, n); // Will return |n| out of setjmp
  18 }
  19
  20 TEST(LlvmLibcSetJmpTest, SetAndJumpBack) {
  21   // Local variables in setjmp scope should be declared volatile.
  22   volatile int n = 0;
  23   // The first time setjmp is called, it should return 0.
  24   // Subsequent calls will return the value passed to jump_back below.
  25   if (__llvm_libc::setjmp(buf) <= MAX_LOOP) {
  26     ++n;
  27     jump_back(n);
  28   }
  29   ASSERT_EQ(n, MAX_LOOP + 1);
  30 }