Adjust libc++ test infastructure to fully support modules

This patch overhalls the libc++ test format/configuration in order to fully support modules. By "fully support" I mean get almost all of the tests passing. The main hurdle for doing this is handling tests that `#define _LIBCPP_FOO` macros to test a different configuration. This patch deals with these tests in the following ways:

1. For tests that define single `_LIBCPP_ABI_FOO` macros have been annotated with `// MODULES_DEFINES: _LIBCPP_ABI_FOO`. This allows the test suite to define the macro on the command line so it uses a different set of modules.
2. Tests for libc++'s debug mode (which define custom `_LIBCPP_ASSERT`) are automatically detected by the test suite and are compiled and run with modules disabled.

This patch also cleans up how the `CXXCompiler` helper class handles enabling/disabling language features.

NOTE: This patch uses `LIT` features which were only committed to LLVM today. If this patch breaks running the libc++ tests you probably need to update LLVM.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@288728 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_adopt_lock.pass.cpp

@@ -10,16 +10,13 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class ...Mutex> class lock_guard;
 
 // lock_guard(Mutex&..., adopt_lock_t);
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 #include <cassert>

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_assign.fail.cpp

@@ -10,16 +10,13 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class ...Mutex> class lock_guard;
 
 // lock_guard& operator=(lock_guard const&) = delete;
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_copy.fail.cpp

@@ -10,16 +10,13 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class ...Mutex> class lock_guard;
 
 // lock_guard(lock_guard const&) = delete;
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_mutex.fail.cpp

@@ -10,16 +10,13 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class ...Mutex> class lock_guard;
 
 // explicit lock_guard(Mutex&...);
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_mutex.pass.cpp

@@ -10,16 +10,13 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class ...Mutex> class lock_guard;
 
 // explicit lock_guard(mutex_type& m);
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 #include <cassert>

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_mutex_cxx03.pass.cpp

@@ -16,5 +16,6 @@
 // dialects, including C++03, even though it is forward declared using
 // variadic templates.
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include "mutex.pass.cpp" // Use the existing non-variadic test

test/std/thread/thread.mutex/thread.lock/thread.lock.guard/variadic_types.pass.cpp

@@ -10,10 +10,6 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03
 
-// FIXME: When modules are enabled we can't affect the contents of <mutex>
-// by defining a macro
-// XFAIL: -fmodules
-
 // <mutex>
 
 // template <class Mutex>
@@ -24,6 +20,7 @@
 //     ...
 // };
 
+// MODULES_DEFINES: _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #define _LIBCPP_ABI_VARIADIC_LOCK_GUARD
 #include <mutex>
 #include <type_traits>

test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++98, c++03, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_duration.pass.cpp

@@ -9,7 +9,7 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <mutex>
 

test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_time_point.pass.cpp

@@ -9,7 +9,7 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11, c++14
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock_shared.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11, c++14
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock_shared.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11, c++14
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock_shared.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_for.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_for.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_until.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>
 

test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until.pass.cpp

@@ -10,7 +10,7 @@
 // UNSUPPORTED: libcpp-has-no-threads
 // UNSUPPORTED: c++03, c++98, c++11
 
-// FLAKY_TEST
+// FLAKY_TEST.
 
 // <shared_mutex>