Resubmit "[lit] Force site configs to run before source-tree configs"

This is a resubmission of r313270.  It broke standalone builds of
compiler-rt because we were not correctly generating the llvm-lit
script in the standalone build directory.

The fixes incorporated here attempt to find llvm/utils/llvm-lit
from the source tree returned by llvm-config.  If present, it
will generate llvm-lit into the output directory.  Regardless,
the user can specify -DLLVM_EXTERNAL_LIT to point to a specific
lit.py on their file system.  This supports the use case of
someone installing lit via a package manager.  If it cannot find
a source tree, and -DLLVM_EXTERNAL_LIT is either unspecified or
invalid, then we print a warning that tests will not be able
to run.

Differential Revision: https://reviews.llvm.org/D37756

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@313407 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 15 insertions, 150 deletions

diff --git a/runtime/CMakeLists.txt b/runtime/CMakeLists.txt
index 470f190209..f89cd4903f 100644
--- a/runtime/CMakeLists.txt
+++ b/runtime/CMakeLists.txt
@@ -77,6 +77,7 @@ if(LLVM_BUILD_EXTERNAL_COMPILER_RT AND EXISTS ${COMPILER_RT_SRC_ROOT}/)
                -DCOMPILER_RT_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
                -DLLVM_LIBDIR_SUFFIX=${LLVM_LIBDIR_SUFFIX}
+               -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
                -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET}
                -DCMAKE_OSX_SYSROOT:PATH=${CMAKE_OSX_SYSROOT}
                ${COMPILER_RT_PASSTHROUGH_VARIABLES}
diff --git a/test/Unit/lit.cfg b/test/Unit/lit.cfg
index 90eb2ac604..c4794ccbe5 100644
--- a/test/Unit/lit.cfg
+++ b/test/Unit/lit.cfg
@@ -17,14 +17,11 @@ config.suffixes = []
 
 # test_source_root: The root path where tests are located.
 # test_exec_root: The root path where tests should be run.
-clang_obj_root = getattr(config, 'clang_obj_root', None)
-if clang_obj_root is not None:
-    config.test_exec_root = os.path.join(clang_obj_root, 'unittests')
-    config.test_source_root = config.test_exec_root
+config.test_exec_root = os.path.join(config.clang_obj_root, 'unittests')
+config.test_source_root = config.test_exec_root
 
 # testFormat: The test format to use to interpret tests.
-llvm_build_mode = getattr(config, 'llvm_build_mode', "Debug")
-config.test_format = lit.formats.GoogleTest(llvm_build_mode, 'Tests')
+config.test_format = lit.formats.GoogleTest(config.llvm_build_mode, 'Tests')
 
 # Propagate the temp directory. Windows requires this because it uses \Windows\
 # if none of these are present.
@@ -38,55 +35,6 @@ for symbolizer in ['ASAN_SYMBOLIZER_PATH', 'MSAN_SYMBOLIZER_PATH']:
     if symbolizer in os.environ:
         config.environment[symbolizer] = os.environ[symbolizer]
 
-###
-
-# Check that the object root is known.
-if config.test_exec_root is None:
-    # Otherwise, we haven't loaded the site specific configuration (the user is
-    # probably trying to run on a test file directly, and either the site
-    # configuration hasn't been created by the build system, or we are in an
-    # out-of-tree build situation).
-
-    # Check for 'clang_unit_site_config' user parameter, and use that if available.
-    site_cfg = lit_config.params.get('clang_unit_site_config', None)
-    if site_cfg and os.path.exists(site_cfg):
-        lit_config.load_config(config, site_cfg)
-        raise SystemExit
-
-    # Try to detect the situation where we are using an out-of-tree build by
-    # looking for 'llvm-config'.
-    #
-    # FIXME: I debated (i.e., wrote and threw away) adding logic to
-    # automagically generate the lit.site.cfg if we are in some kind of fresh
-    # build situation. This means knowing how to invoke the build system
-    # though, and I decided it was too much magic.
-
-    llvm_config = lit.util.which('llvm-config', config.environment['PATH'])
-    if not llvm_config:
-        lit_config.fatal('No site specific configuration available!')
-
-    # Get the source and object roots.
-    llvm_src_root = subprocess.check_output(['llvm-config', '--src-root']).strip()
-    llvm_obj_root = subprocess.check_output(['llvm-config', '--obj-root']).strip()
-    clang_src_root = os.path.join(llvm_src_root, "tools", "clang")
-    clang_obj_root = os.path.join(llvm_obj_root, "tools", "clang")
-
-    # Validate that we got a tree which points to here, using the standard
-    # tools/clang layout.
-    this_src_root = os.path.join(os.path.dirname(__file__),'..','..')
-    if os.path.realpath(clang_src_root) != os.path.realpath(this_src_root):
-        lit_config.fatal('No site specific configuration available!')
-
-    # Check that the site specific configuration exists.
-    site_cfg = os.path.join(clang_obj_root, 'test', 'Unit', 'lit.site.cfg')
-    if not os.path.exists(site_cfg):
-        lit_config.fatal('No site specific configuration available!')
-
-    # Okay, that worked. Notify the user of the automagic, and reconfigure.
-    lit_config.note('using out-of-tree build at %r' % clang_obj_root)
-    lit_config.load_config(config, site_cfg)
-    raise SystemExit
-
 shlibpath_var = ''
 if platform.system() == 'Linux':
     shlibpath_var = 'LD_LIBRARY_PATH'
@@ -97,14 +45,7 @@ elif platform.system() == 'Windows':
 
 # in stand-alone builds, shlibdir is clang's build tree
 # while llvm_libs_dir is installed LLVM (and possibly older clang)
-llvm_shlib_dir = getattr(config, 'shlibdir', None)
-if not llvm_shlib_dir:
-    lit_config.fatal('No shlibdir set!')
-# Point the dynamic loader at dynamic libraries in 'lib'.
-llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
-if not llvm_libs_dir:
-    lit_config.fatal('No LLVM libs dir set!')
-shlibpath = os.path.pathsep.join((llvm_shlib_dir, llvm_libs_dir,
+shlibpath = os.path.pathsep.join((config.shlibdir, config.llvm_libs_dir,
                                  config.environment.get(shlibpath_var,'')))
 
 config.environment[shlibpath_var] = shlibpath
diff --git a/test/lit.cfg b/test/lit.cfg
index 6b7159ced8..d258286274 100644
--- a/test/lit.cfg
+++ b/test/lit.cfg
@@ -55,13 +55,7 @@ config.excludes = ['Inputs', 'CMakeLists.txt', 'README.txt', 'LICENSE.txt']
 config.test_source_root = os.path.dirname(__file__)
 
 # test_exec_root: The root path where tests should be run.
-clang_obj_root = getattr(config, 'clang_obj_root', None)
-if clang_obj_root is not None:
-    config.test_exec_root = os.path.join(clang_obj_root, 'test')
-
-# Set llvm_{src,obj}_root for use by others.
-config.llvm_src_root = getattr(config, 'llvm_src_root', None)
-config.llvm_obj_root = getattr(config, 'llvm_obj_root', None)
+config.test_exec_root = os.path.join(config.clang_obj_root, 'test')
 
 # Clear some environment variables that might affect Clang.
 #
@@ -92,91 +86,20 @@ for name in possibly_dangerous_env_vars:
     del config.environment[name]
 
 # Tweak the PATH to include the tools dir and the scripts dir.
-if clang_obj_root is not None:
-    clang_tools_dir = getattr(config, 'clang_tools_dir', None)
-    if not clang_tools_dir:
-        lit_config.fatal('No Clang tools dir set!')
-    llvm_tools_dir = getattr(config, 'llvm_tools_dir', None)
-    if not llvm_tools_dir:
-        lit_config.fatal('No LLVM tools dir set!')
-    path = os.path.pathsep.join((
-            clang_tools_dir, llvm_tools_dir, config.environment['PATH']))
-    config.environment['PATH'] = path
-    # in stand-alone builds, llvm_shlib_dir is clang's build tree
-    # while llvm_libs_dir is installed LLVM (and possibly older clang)
-    llvm_shlib_dir = getattr(config, 'llvm_shlib_dir', None)
-    if not llvm_shlib_dir:
-        lit_config.fatal('No LLVM shlib dir set!')
-    llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
-    if not llvm_libs_dir:
-        lit_config.fatal('No LLVM libs dir set!')
-    path = os.path.pathsep.join((llvm_shlib_dir, llvm_libs_dir,
-                                 config.environment.get('LD_LIBRARY_PATH','')))
-    config.environment['LD_LIBRARY_PATH'] = path
+path = os.path.pathsep.join((
+        config.clang_tools_dir, config.llvm_tools_dir, config.environment['PATH']))
+config.environment['PATH'] = path
+path = os.path.pathsep.join((config.llvm_shlib_dir, config.llvm_libs_dir,
+                              config.environment.get('LD_LIBRARY_PATH','')))
+config.environment['LD_LIBRARY_PATH'] = path
 
 # Propagate path to symbolizer for ASan/MSan.
 for symbolizer in ['ASAN_SYMBOLIZER_PATH', 'MSAN_SYMBOLIZER_PATH']:
     if symbolizer in os.environ:
         config.environment[symbolizer] = os.environ[symbolizer]
 
-###
-
-# Check that the object root is known.
-if config.test_exec_root is None:
-    # Otherwise, we haven't loaded the site specific configuration (the user is
-    # probably trying to run on a test file directly, and either the site
-    # configuration hasn't been created by the build system, or we are in an
-    # out-of-tree build situation).
-
-    # Check for 'clang_site_config' user parameter, and use that if available.
-    site_cfg = lit_config.params.get('clang_site_config', None)
-    if site_cfg and os.path.exists(site_cfg):
-        lit_config.load_config(config, site_cfg)
-        raise SystemExit
-
-    # Try to detect the situation where we are using an out-of-tree build by
-    # looking for 'llvm-config'.
-    #
-    # FIXME: I debated (i.e., wrote and threw away) adding logic to
-    # automagically generate the lit.site.cfg if we are in some kind of fresh
-    # build situation. This means knowing how to invoke the build system though,
-    # and I decided it was too much magic. We should solve this by just having
-    # the .cfg files generated during the configuration step.
-
-    llvm_config = lit.util.which('llvm-config', config.environment['PATH'])
-    if not llvm_config:
-        lit_config.fatal('No site specific configuration available!')
-
-    # Get the source and object roots.
-    llvm_src_root = subprocess.check_output(['llvm-config', '--src-root']).strip()
-    llvm_obj_root = subprocess.check_output(['llvm-config', '--obj-root']).strip()
-    clang_src_root = os.path.join(llvm_src_root, "tools", "clang")
-    clang_obj_root = os.path.join(llvm_obj_root, "tools", "clang")
-
-    # Validate that we got a tree which points to here, using the standard
-    # tools/clang layout.
-    this_src_root = os.path.dirname(config.test_source_root)
-    if os.path.realpath(clang_src_root) != os.path.realpath(this_src_root):
-        lit_config.fatal('No site specific configuration available!')
-
-    # Check that the site specific configuration exists.
-    site_cfg = os.path.join(clang_obj_root, 'test', 'lit.site.cfg')
-    if not os.path.exists(site_cfg):
-        lit_config.fatal(
-            'No site specific configuration available! You may need to '
-            'run "make test" in your Clang build directory.')
-
-    # Okay, that worked. Notify the user of the automagic, and reconfigure.
-    lit_config.note('using out-of-tree build at %r' % clang_obj_root)
-    lit_config.load_config(config, site_cfg)
-    raise SystemExit
-
-###
-
 # Discover the 'clang' and 'clangcc' to use.
 
-import os
-
 def inferClang(PATH):
     # Determine which clang to use.
     clang = os.getenv('CLANG')
@@ -315,7 +238,7 @@ config.substitutions.append(
 # with the full path to the build directory holding that tool.  This
 # ensures that we are testing the tools just built and not some random
 # tools that might happen to be in the user's PATH.
-tool_dirs = os.path.pathsep.join((clang_tools_dir, llvm_tools_dir))
+tool_dirs = os.path.pathsep.join((config.clang_tools_dir, config.llvm_tools_dir))
 
 # Regex assertions to reject neighbor hyphens/dots (seen in some tests).
 # For example, don't match 'clang-check-' or '.clang-format'.
@@ -351,7 +274,7 @@ for pattern in tool_patterns:
     if not tool_path:
         # Warn, but still provide a substitution.
         lit_config.note('Did not find ' + tool_name + ' in ' + tool_dirs)
-        tool_path = clang_tools_dir + '/' + tool_name
+        tool_path = config.clang_tools_dir + '/' + tool_name
     config.substitutions.append((pattern, tool_pipe + tool_path))
 
 ###
@@ -451,7 +374,7 @@ def get_llvm_config_props():
 
     cmd = subprocess.Popen(
         [
-            os.path.join(llvm_tools_dir, 'llvm-config'),
+            os.path.join(config.llvm_tools_dir, 'llvm-config'),
             '--assertion-mode',
             '--targets-built',
             '--cxxflags'