1 //===-- ThreadLauncher.cpp ---------------------------------------*- C++
2 //-*-===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // lldb Includes
11 #include "lldb/Host/ThreadLauncher.h"
12 #include "lldb/Host/HostNativeThread.h"
13 #include "lldb/Host/HostThread.h"
14 #include "lldb/Utility/Log.h"
15 
16 #if defined(_WIN32)
17 #include "lldb/Host/windows/windows.h"
18 #endif
19 
20 using namespace lldb;
21 using namespace lldb_private;
22 
23 llvm::Expected<HostThread> ThreadLauncher::LaunchThread(
24     llvm::StringRef name, lldb::thread_func_t thread_function,
25     lldb::thread_arg_t thread_arg, size_t min_stack_byte_size) {
26   // Host::ThreadCreateTrampoline will delete this pointer for us.
27   HostThreadCreateInfo *info_ptr =
28       new HostThreadCreateInfo(name.data(), thread_function, thread_arg);
29   lldb::thread_t thread;
30 #ifdef _WIN32
31   thread = (lldb::thread_t)::_beginthreadex(
32       0, (unsigned)min_stack_byte_size,
33       HostNativeThread::ThreadCreateTrampoline, info_ptr, 0, NULL);
34   if (thread == (lldb::thread_t)(-1L))
35     return llvm::errorCodeToError(::GetLastError());
36 #else
37 
38 // ASAN instrumentation adds a lot of bookkeeping overhead on stack frames.
39 #if __has_feature(address_sanitizer)
40   const size_t eight_megabytes = 8 * 1024 * 1024;
41   if (min_stack_byte_size < eight_megabytes) {
42     min_stack_byte_size += eight_megabytes;
43   }
44 #endif
45 
46   pthread_attr_t *thread_attr_ptr = nullptr;
47   pthread_attr_t thread_attr;
48   bool destroy_attr = false;
49   if (min_stack_byte_size > 0) {
50     if (::pthread_attr_init(&thread_attr) == 0) {
51       destroy_attr = true;
52       size_t default_min_stack_byte_size = 0;
53       if (::pthread_attr_getstacksize(&thread_attr,
54                                       &default_min_stack_byte_size) == 0) {
55         if (default_min_stack_byte_size < min_stack_byte_size) {
56           if (::pthread_attr_setstacksize(&thread_attr, min_stack_byte_size) ==
57               0)
58             thread_attr_ptr = &thread_attr;
59         }
60       }
61     }
62   }
63   int err =
64       ::pthread_create(&thread, thread_attr_ptr,
65                        HostNativeThread::ThreadCreateTrampoline, info_ptr);
66 
67   if (destroy_attr)
68     ::pthread_attr_destroy(&thread_attr);
69 
70   if (err)
71     return llvm::errorCodeToError(
72         std::error_code(err, std::generic_category()));
73 #endif
74 
75   return HostThread(thread);
76 }
77