Function launch_threads

Source/astcenccli_platform_dependents.cpp:246–313

See header for documentation */

/* See header for documentation */
void launch_threads(
	const char* operation,
	int thread_count,
	void (*func)(int, int, void*),
	void *payload
) {
	// Directly execute single threaded workloads on this thread
	if (thread_count <= 1)
	{
		func(1, 0, payload);
		return;
	}

	// Otherwise spawn worker threads
	std::vector<launch_desc> thread_descs(thread_count);
	int actual_thread_count { 0 };

	for (int i = 0; i < thread_count; i++)
	{
		thread_descs[actual_thread_count].thread_count = thread_count;
		thread_descs[actual_thread_count].thread_id = actual_thread_count;
		thread_descs[actual_thread_count].payload = payload;
		thread_descs[actual_thread_count].func = func;

		// Handle pthread_create failing by simply using fewer threads
		int error = pthread_create(
			&(thread_descs[actual_thread_count].thread_handle),
			nullptr,
			launch_threads_helper,
			reinterpret_cast<void*>(&thread_descs[actual_thread_count]));

		// Track how many threads we actually created
		if (!error)
		{
			// Windows needs explicit thread assignment to handle large core count systems
			#if defined(_WIN32) && !defined(__CYGWIN__)
				set_group_affinity(
					thread_descs[actual_thread_count].thread_handle,
					actual_thread_count);
			#endif

			actual_thread_count++;
		}
	}

	// If we did not create thread_count threads then emit a warning
	if (actual_thread_count != thread_count)
	{
		int log_count = actual_thread_count == 0 ? 1 : actual_thread_count;
		const char* log_s = log_count == 1 ? "" : "s";
		printf("WARNING: %s using %d thread%s due to thread creation error\n\n",
		       operation, log_count, log_s);
	}

	// If we managed to spawn any threads wait for them to complete
	if (actual_thread_count != 0)
	{
		for (int i = 0; i < actual_thread_count; i++)