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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 verifies the correct handling of child thread exits.
#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_barrier1;
std::atomic_int g_barrier2;
std::atomic_int g_barrier3;
void *
thread1 ()
{
// Synchronize with the main thread.
pseudo_barrier_wait(g_barrier1);
// Synchronize with the main thread and thread2.
pseudo_barrier_wait(g_barrier2);
// Return
return NULL; // Set second breakpoint here
}
void *
thread2 ()
{
// Synchronize with thread1 and the main thread.
pseudo_barrier_wait(g_barrier2);
// Synchronize with the main thread.
pseudo_barrier_wait(g_barrier3);
// Return
return NULL;
}
int main ()
{
pseudo_barrier_init(g_barrier1, 2);
pseudo_barrier_init(g_barrier2, 3);
pseudo_barrier_init(g_barrier3, 2);
// Create a thread.
std::thread thread_1(thread1);
// Wait for thread1 to start.
pseudo_barrier_wait(g_barrier1);
// Create another thread.
std::thread thread_2(thread2); // Set first breakpoint here
// Wait for thread2 to start.
pseudo_barrier_wait(g_barrier2);
// Wait for the first thread to finish
thread_1.join();
// Synchronize with the remaining thread
pseudo_barrier_wait(g_barrier3); // Set third breakpoint here
// Wait for the second thread to finish
thread_2.join();
return 0; // Set fourth breakpoint here
}
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