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//===-- main.cpp ------------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// This test is intended to create a situation in which one thread will be
// created while the debugger is stepping in another thread.
#include <atomic>
#include <thread>
// Note that although hogging the CPU while waiting for a variable to change
// would be terrible in production code, it's great for testing since it
// avoids a lot of messy context switching to get multiple threads synchronized.
#define do_nothing()
#define pseudo_barrier_wait(bar) \
--bar; \
while (bar > 0) \
do_nothing();
#define pseudo_barrier_init(bar, count) (bar = count)
std::atomic_int g_barrier;
volatile int g_thread_created = 0;
volatile int g_test = 0;
void *
step_thread_func ()
{
g_test = 0; // Set breakpoint here
while (!g_thread_created)
g_test++;
// One more time to provide a continue point
g_test++; // Continue from here
// Return
return NULL;
}
void *
create_thread_func (void *input)
{
std::thread *step_thread = (std::thread*)input;
// Wait until the main thread knows this thread is started.
pseudo_barrier_wait(g_barrier);
// Wait until the other thread is done.
step_thread->join();
// Return
return NULL;
}
int main ()
{
// Use a simple count to simulate a barrier.
pseudo_barrier_init(g_barrier, 2);
// Create a thread to hit the breakpoint.
std::thread thread_1(step_thread_func);
// Wait until the step thread is stepping
while (g_test < 1)
do_nothing();
// Create a thread to exit while we're stepping.
std::thread thread_2(create_thread_func, &thread_1);
// Wait until that thread is started
pseudo_barrier_wait(g_barrier);
// Let the stepping thread know the other thread is there
g_thread_created = 1;
// Wait for the threads to finish.
thread_2.join();
thread_1.join();
return 0;
}
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