[gn build] Start adding build files for LLVM unittests

Adds build files for //llvm/unittest/[A-D].

Also teach sync_source_lists_from_cmake.py to not complain about missing
BUILD.gn files for CMakeLists.txt files that just call add_subdirectory()
without calling add_.+_unittest, like e.g.
llvm/unittests/Target/CMakeLists.txt.

(Omits CodeGen/GlobalISel and DebugInfo/PDB because their build files are somewhat interesting, and this patch is already on the larger side.)

Differential Revision: https://reviews.llvm.org/D56212

llvm-svn: 350411

1 files changed, 8 insertions, 2 deletions

diff --git a/llvm/utils/gn/build/sync_source_lists_from_cmake.py b/llvm/utils/gn/build/sync_source_lists_from_cmake.py
index f5d92ce0bba..03cba7ad396 100755
--- a/llvm/utils/gn/build/sync_source_lists_from_cmake.py
+++ b/llvm/utils/gn/build/sync_source_lists_from_cmake.py
@@ -21,9 +21,9 @@ def sync_source_lists():
     gn_files = subprocess.check_output(
             ['git', 'ls-files', '*BUILD.gn']).splitlines()
 
-    # Matches e.g. |   "foo.cpp",|.
+    # Matches e.g. |   "foo.cpp",|, captures |foo| in group 1.
     gn_cpp_re = re.compile(r'^\s*"([^"]+\.(?:cpp|h))",$', re.MULTILINE)
-    # Matches e.g. |   "foo.cpp"|.
+    # Matches e.g. |   foo.cpp|, captures |foo| in group 1.
     cmake_cpp_re = re.compile(r'^\s*([A-Za-z_0-9/-]+\.(?:cpp|h))$',
                               re.MULTILINE)
 
@@ -57,12 +57,18 @@ def sync_source_lists():
 
 
 def sync_unittests():
+    # Matches e.g. |add_llvm_unittest_with_input_files|.
+    unittest_re = re.compile(r'^add_\S+_unittest', re.MULTILINE)
+
+    # FIXME: Add 'llvm' here once it's complete.
     checked = [ 'clang', 'lld' ]
     for c in checked:
         for root, _, _ in os.walk(os.path.join(c, 'unittests')):
             cmake_file = os.path.join(root, 'CMakeLists.txt')
             if not os.path.exists(cmake_file):
                 continue
+            if not unittest_re.search(open(cmake_file).read()):
+                continue  # Skip CMake files that just add subdirectories.
             gn_file = os.path.join('llvm/utils/gn/secondary', root, 'BUILD.gn')
             if not os.path.exists(gn_file):
                 print('missing GN file %s for unittest CMake file %s' %