diff --git a/lldb/include/lldb/Host/File.h b/lldb/include/lldb/Host/File.h
--- a/lldb/include/lldb/Host/File.h
+++ b/lldb/include/lldb/Host/File.h
@@ -10,7 +10,7 @@
 #define LLDB_HOST_FILE_H
 
 #include "lldb/Host/PosixApi.h"
-#include "lldb/Utility/IOObject.h"
+#include "llvm/Utility/IOObject.h"
 #include "lldb/Utility/Status.h"
 #include "lldb/lldb-private.h"
 #include "llvm/ADT/BitmaskEnum.h"
diff --git a/lldb/include/lldb/Host/MainLoopBase.h b/lldb/include/lldb/Host/MainLoopBase.h
--- a/lldb/include/lldb/Host/MainLoopBase.h
+++ b/lldb/include/lldb/Host/MainLoopBase.h
@@ -9,9 +9,9 @@
 #ifndef LLDB_HOST_MAINLOOPBASE_H
 #define LLDB_HOST_MAINLOOPBASE_H
 
-#include "lldb/Utility/IOObject.h"
 #include "lldb/Utility/Status.h"
 #include "llvm/Support/ErrorHandling.h"
+#include "llvm/Utility/IOObject.h"
 #include <functional>
 
 namespace lldb_private {
diff --git a/lldb/include/lldb/Host/posix/ConnectionFileDescriptorPosix.h b/lldb/include/lldb/Host/posix/ConnectionFileDescriptorPosix.h
--- a/lldb/include/lldb/Host/posix/ConnectionFileDescriptorPosix.h
+++ b/lldb/include/lldb/Host/posix/ConnectionFileDescriptorPosix.h
@@ -17,8 +17,8 @@
 
 #include "lldb/Host/Pipe.h"
 #include "lldb/Utility/Connection.h"
-#include "lldb/Utility/IOObject.h"
 #include "lldb/Utility/Predicate.h"
+#include "llvm/Utility/IOObject.h"
 
 namespace lldb_private {
 
diff --git a/lldb/source/Host/common/Socket.cpp b/lldb/source/Host/common/Socket.cpp
--- a/lldb/source/Host/common/Socket.cpp
+++ b/lldb/source/Host/common/Socket.cpp
@@ -12,7 +12,7 @@
 #include "lldb/Host/Host.h"
 #include "lldb/Host/SocketAddress.h"
 #include "lldb/Host/StringConvert.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "lldb/Host/common/UDPSocket.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/Utility/RegularExpression.h"
diff --git a/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp b/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
--- a/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
+++ b/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
@@ -41,7 +41,7 @@
 #endif
 #include "lldb/Host/Host.h"
 #include "lldb/Host/Socket.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "lldb/Host/common/UDPSocket.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/Utility/StreamString.h"
diff --git a/lldb/source/Plugins/Platform/Android/PlatformAndroidRemoteGDBServer.cpp b/lldb/source/Plugins/Platform/Android/PlatformAndroidRemoteGDBServer.cpp
--- a/lldb/source/Plugins/Platform/Android/PlatformAndroidRemoteGDBServer.cpp
+++ b/lldb/source/Plugins/Platform/Android/PlatformAndroidRemoteGDBServer.cpp
@@ -7,10 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "lldb/Host/ConnectionFileDescriptor.h"
-#include "lldb/Host/common/TCPSocket.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/Utility/Status.h"
 #include "lldb/Utility/UriParser.h"
+#include "llvm/Host/common/TCPSocket.h"
 
 #include "PlatformAndroidRemoteGDBServer.h"
 
diff --git a/lldb/source/Plugins/Process/MacOSX-Kernel/ProcessKDP.cpp b/lldb/source/Plugins/Process/MacOSX-Kernel/ProcessKDP.cpp
--- a/lldb/source/Plugins/Process/MacOSX-Kernel/ProcessKDP.cpp
+++ b/lldb/source/Plugins/Process/MacOSX-Kernel/ProcessKDP.cpp
@@ -19,7 +19,7 @@
 #include "lldb/Host/ConnectionFileDescriptor.h"
 #include "lldb/Host/Host.h"
 #include "lldb/Host/ThreadLauncher.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "lldb/Interpreter/CommandInterpreter.h"
 #include "lldb/Interpreter/CommandObject.h"
 #include "lldb/Interpreter/CommandObjectMultiword.h"
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -24,7 +24,7 @@
 #include "lldb/Host/Socket.h"
 #include "lldb/Host/StringConvert.h"
 #include "lldb/Host/ThreadLauncher.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "lldb/Host/posix/ConnectionFileDescriptorPosix.h"
 #include "lldb/Target/Platform.h"
 #include "lldb/Utility/Event.h"
diff --git a/lldb/source/Utility/CMakeLists.txt b/lldb/source/Utility/CMakeLists.txt
--- a/lldb/source/Utility/CMakeLists.txt
+++ b/lldb/source/Utility/CMakeLists.txt
@@ -39,7 +39,6 @@
   Event.cpp
   FileSpec.cpp
   GDBRemote.cpp
-  IOObject.cpp
   LLDBAssert.cpp
   Listener.cpp
   Log.cpp
diff --git a/lldb/tools/lldb-server/Acceptor.cpp b/lldb/tools/lldb-server/Acceptor.cpp
--- a/lldb/tools/lldb-server/Acceptor.cpp
+++ b/lldb/tools/lldb-server/Acceptor.cpp
@@ -12,9 +12,9 @@
 #include "llvm/Support/ScopedPrinter.h"
 
 #include "lldb/Host/ConnectionFileDescriptor.h"
-#include "lldb/Host/common/TCPSocket.h"
 #include "lldb/Utility/StreamString.h"
 #include "lldb/Utility/UriParser.h"
+#include "llvm/Host/common/TCPSocket.h"
 
 using namespace lldb;
 using namespace lldb_private;
diff --git a/lldb/tools/lldb-server/lldb-platform.cpp b/lldb/tools/lldb-server/lldb-platform.cpp
--- a/lldb/tools/lldb-server/lldb-platform.cpp
+++ b/lldb/tools/lldb-server/lldb-platform.cpp
@@ -32,7 +32,7 @@
 #include "lldb/Host/ConnectionFileDescriptor.h"
 #include "lldb/Host/HostGetOpt.h"
 #include "lldb/Host/OptionParser.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "lldb/Utility/FileSpec.h"
 #include "lldb/Utility/Status.h"
 
diff --git a/lldb/unittests/Host/MainLoopTest.cpp b/lldb/unittests/Host/MainLoopTest.cpp
--- a/lldb/unittests/Host/MainLoopTest.cpp
+++ b/lldb/unittests/Host/MainLoopTest.cpp
@@ -10,7 +10,7 @@
 #include "TestingSupport/SubsystemRAII.h"
 #include "lldb/Host/ConnectionFileDescriptor.h"
 #include "lldb/Host/PseudoTerminal.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
 #include <future>
diff --git a/lldb/unittests/Host/SocketTestUtilities.h b/lldb/unittests/Host/SocketTestUtilities.h
--- a/lldb/unittests/Host/SocketTestUtilities.h
+++ b/lldb/unittests/Host/SocketTestUtilities.h
@@ -15,8 +15,8 @@
 
 #include "lldb/Host/Config.h"
 #include "lldb/Host/Socket.h"
-#include "lldb/Host/common/TCPSocket.h"
 #include "lldb/Host/common/UDPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Testing/Support/Error.h"
diff --git a/lldb/unittests/debugserver/RNBSocketTest.cpp b/lldb/unittests/debugserver/RNBSocketTest.cpp
--- a/lldb/unittests/debugserver/RNBSocketTest.cpp
+++ b/lldb/unittests/debugserver/RNBSocketTest.cpp
@@ -16,7 +16,7 @@
 #include "RNBSocket.h"
 #include "lldb/Host/Socket.h"
 #include "lldb/Host/StringConvert.h"
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "llvm/Testing/Support/Error.h"
 
 using namespace lldb_private;
diff --git a/lldb/unittests/tools/lldb-server/tests/TestClient.cpp b/lldb/unittests/tools/lldb-server/tests/TestClient.cpp
--- a/lldb/unittests/tools/lldb-server/tests/TestClient.cpp
+++ b/lldb/unittests/tools/lldb-server/tests/TestClient.cpp
@@ -8,10 +8,10 @@
 
 #include "TestClient.h"
 #include "lldb/Host/HostInfo.h"
-#include "lldb/Host/common/TCPSocket.h"
 #include "lldb/Host/posix/ConnectionFileDescriptorPosix.h"
 #include "lldb/Utility/Args.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Host/common/TCPSocket.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
diff --git a/lldb/include/lldb/Host/Socket.h b/llvm/include/llvm/Host/Socket.h
rename from lldb/include/lldb/Host/Socket.h
rename to llvm/include/llvm/Host/Socket.h
--- a/lldb/include/lldb/Host/Socket.h
+++ b/llvm/include/llvm/Host/Socket.h
@@ -15,9 +15,9 @@
 #include "lldb/lldb-private.h"
 
 #include "lldb/Host/SocketAddress.h"
-#include "lldb/Utility/IOObject.h"
 #include "lldb/Utility/Predicate.h"
 #include "lldb/Utility/Status.h"
+#include "llvm/Utility/IOObject.h"
 
 #ifdef _WIN32
 #include "lldb/Host/windows/windows.h"
diff --git a/lldb/include/lldb/Host/SocketAddress.h b/llvm/include/llvm/Host/SocketAddress.h
rename from lldb/include/lldb/Host/SocketAddress.h
rename to llvm/include/llvm/Host/SocketAddress.h
diff --git a/lldb/include/lldb/Host/common/TCPSocket.h b/llvm/include/llvm/Host/common/TCPSocket.h
rename from lldb/include/lldb/Host/common/TCPSocket.h
rename to llvm/include/llvm/Host/common/TCPSocket.h
diff --git a/lldb/include/lldb/Utility/IOObject.h b/llvm/include/llvm/Utility/IOObject.h
rename from lldb/include/lldb/Utility/IOObject.h
rename to llvm/include/llvm/Utility/IOObject.h
diff --git a/llvm/lib/CMakeLists.txt b/llvm/lib/CMakeLists.txt
--- a/llvm/lib/CMakeLists.txt
+++ b/llvm/lib/CMakeLists.txt
@@ -36,6 +36,7 @@
 add_subdirectory(TextAPI)
 add_subdirectory(ToolDrivers)
 add_subdirectory(XRay)
+add_subdirectory(Host)
 if (LLVM_INCLUDE_TESTS)
   add_subdirectory(Testing)
 endif()
diff --git a/llvm/lib/Host/CMakeLists.txt b/llvm/lib/Host/CMakeLists.txt
new file mode 100644
--- /dev/null
+++ b/llvm/lib/Host/CMakeLists.txt
@@ -0,0 +1,16 @@
+if (APPLE AND LLVM_ENABLE_LOCAL_SUBMODULE_VISIBILITY)
+  # The arpa/inet.h header used in the files here is providing a miscompiled
+  # htonl function on macOS <= 10.15 when local submodule visibility is active.
+  # Disabling modules in this directory until this is is fixed.
+  # See rdar://problem/62886385
+  remove_module_flags()
+endif()
+
+macro(add_host_subdirectory group)
+  list(APPEND HOST_SOURCES ${ARGN})
+  source_group(${group} FILES ${ARGN})
+endmacro()
+
+add_host_subdirectory(common
+  common/TCPSocket.cpp
+)
diff --git a/lldb/source/Host/common/TCPSocket.cpp b/llvm/lib/Host/common/TCPSocket.cpp
rename from lldb/source/Host/common/TCPSocket.cpp
rename to llvm/lib/Host/common/TCPSocket.cpp
--- a/lldb/source/Host/common/TCPSocket.cpp
+++ b/llvm/lib/Host/common/TCPSocket.cpp
@@ -10,7 +10,7 @@
 #define _WINSOCK_DEPRECATED_NO_WARNINGS
 #endif
 
-#include "lldb/Host/common/TCPSocket.h"
+#include "llvm/Host/common/TCPSocket.h"
 
 #include "lldb/Host/Config.h"
 #include "lldb/Host/MainLoop.h"
@@ -169,8 +169,9 @@
 
     address.SetPort(port);
 
-    if (-1 == llvm::sys::RetryAfterSignal(-1, ::connect,
-          GetNativeSocket(), &address.sockaddr(), address.GetLength())) {
+    if (-1 == llvm::sys::RetryAfterSignal(-1, ::connect, GetNativeSocket(),
+                                          &address.sockaddr(),
+                                          address.GetLength())) {
       CLOSE_SOCKET(GetNativeSocket());
       continue;
     }
@@ -214,7 +215,7 @@
                  sizeof(option_value));
 
     SocketAddress listen_address = address;
-    if(!listen_address.IsLocalhost())
+    if (!listen_address.IsLocalhost())
       listen_address.SetToAnyAddress(address.GetFamily(), port);
     else
       listen_address.SetPort(port);
@@ -268,14 +269,16 @@
     auto inherit = this->m_child_processes_inherit;
     auto io_sp = IOObjectSP(new TCPSocket(socket.first, false, inherit));
     handles.emplace_back(accept_loop.RegisterReadObject(
-        io_sp, [fd, inherit, &sock, &AcceptAddr, &error,
-                        &listen_sock](MainLoopBase &loop) {
+        io_sp,
+        [fd, inherit, &sock, &AcceptAddr, &error,
+         &listen_sock](MainLoopBase &loop) {
           socklen_t sa_len = AcceptAddr.GetMaxLength();
-          sock = AcceptSocket(fd, &AcceptAddr.sockaddr(), &sa_len, inherit,
-                              error);
+          sock =
+              AcceptSocket(fd, &AcceptAddr.sockaddr(), &sa_len, inherit, error);
           listen_sock = fd;
           loop.RequestTermination();
-        }, error));
+        },
+        error));
     if (error.Fail())
       return error;
   }
@@ -287,7 +290,7 @@
     accept_loop.Run();
 
     if (error.Fail())
-        return error;
+      return error;
 
     lldb_private::SocketAddress &AddrIn = m_listen_sockets[listen_sock];
     if (!AddrIn.IsAnyAddr() && AcceptAddr != AddrIn) {
diff --git a/lldb/source/Utility/IOObject.cpp b/llvm/lib/Utility/IOObject.cpp
rename from lldb/source/Utility/IOObject.cpp
rename to llvm/lib/Utility/IOObject.cpp
--- a/lldb/source/Utility/IOObject.cpp
+++ b/llvm/lib/Utility/IOObject.cpp
@@ -6,7 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "lldb/Utility/IOObject.h"
+#include "llvm/Utility/IOObject.h"
 
 using namespace lldb_private;