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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 exit
// while the debugger is stepping in another thread.
#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)
// A barrier to synchronize thread start.
volatile int g_barrier;
volatile int g_thread_exited = 0;
volatile int g_test = 0;
void *
step_thread_func ()
{
// Wait until both threads are started.
pseudo_barrier_wait(g_barrier);
g_test = 0; // Set breakpoint here
while (!g_thread_exited)
g_test++;
// One more time to provide a continue point
g_test++; // Continue from here
// Return
return NULL;
}
void *
exit_thread_func ()
{
// Wait until both threads are started.
pseudo_barrier_wait(g_barrier);
// Wait until the other thread is stepping.
while (g_test == 0)
do_nothing();
// Return
return NULL;
}
int main ()
{
// Synchronize thread start so that doesn't happen during stepping.
pseudo_barrier_init(g_barrier, 2);
// Create a thread to hit the breakpoint.
std::thread thread_1(step_thread_func);
// Create a thread to exit while we're stepping.
std::thread thread_2(exit_thread_func);
// Wait for the exit thread to finish.
thread_2.join();
// Let the stepping thread know the other thread is gone.
g_thread_exited = 1;
// Wait for the stepping thread to finish.
thread_1.join();
return 0;
}
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