Make lit.cfg like the other lit.cfgs so it can be run standalone.

Relies on matching lit change in r163171.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@163172 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 93 insertions, 16 deletions

diff --git a/test/lit.cfg b/test/lit.cfg
index 77a71128..0a084970 100644
--- a/test/lit.cfg
+++ b/test/lit.cfg
@@ -39,9 +39,8 @@ config.test_source_root = os.path.dirname(__file__)
 
 # test_exec_root: The root path where tests should be run.
 clang_tools_binary_dir = getattr(config, 'clang_tools_binary_dir', None)
-if not clang_tools_binary_dir:
-    lit.fatal('No Clang tools binary dir set!')
-config.test_exec_root = os.path.join(clang_tools_binary_dir, 'test')
+if clang_tools_binary_dir is not None:
+    config.test_exec_root = os.path.join(clang_tools_binary_dir, 'test')
 
 # Clear some environment variables that might affect Clang.
 #
@@ -73,27 +72,103 @@ for name in possibly_dangerous_env_vars:
     del config.environment[name]
 
 # Tweak the PATH to include the tools dir and the scripts dir.
-llvm_tools_dir = getattr(config, 'llvm_tools_dir', None)
-if not llvm_tools_dir:
-    lit.fatal('No LLVM tools dir set!')
-path = os.path.pathsep.join((llvm_tools_dir, config.environment['PATH']))
-config.environment['PATH'] = path
-
-llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
-if not llvm_libs_dir:
-    lit.fatal('No LLVM libs dir set!')
-path = os.path.pathsep.join((llvm_libs_dir,
-                             config.environment.get('LD_LIBRARY_PATH','')))
-config.environment['LD_LIBRARY_PATH'] = path
+if clang_tools_binary_dir is not None:
+    llvm_tools_dir = getattr(config, 'llvm_tools_dir', None)
+    if not llvm_tools_dir:
+        lit.fatal('No LLVM tools dir set!')
+    path = os.path.pathsep.join((llvm_tools_dir, config.environment['PATH']))
+    config.environment['PATH'] = path
+
+    llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
+    if not llvm_libs_dir:
+        lit.fatal('No LLVM libs dir set!')
+    path = os.path.pathsep.join((llvm_libs_dir,
+                                 config.environment.get('LD_LIBRARY_PATH','')))
+    config.environment['LD_LIBRARY_PATH'] = path
 
 ###
 
+# 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.params.get('clang_tools_extra_site_config', None)
+    if site_cfg and os.path.exists(site_cfg):
+        lit.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.fatal('No site specific configuration available!')
+
+    # Get the source and object roots.
+    llvm_src_root = lit.util.capture(['llvm-config', '--src-root']).strip()
+    llvm_obj_root = lit.util.capture(['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")
+
+    clang_tools_extra_src_root = os.path.join(clang_src_root, "tools", "extra")
+    clang_tools_extra_obj_root = os.path.join(clang_obj_root, "tools", "extra")
+    # 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_tools_extra_src_root) != os.path.realpath(this_src_root):
+        lit.fatal('No site specific configuration available!')
+
+    # Check that the site specific configuration exists.
+    site_cfg = os.path.join(clang_tools_extra_obj_root, 'test', 'lit.site.cfg')
+    if not os.path.exists(site_cfg):
+        lit.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.note('using out-of-tree build at %r' % clang_obj_root)
+    lit.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')
+
+    # If the user set clang in the environment, definitely use that and don't
+    # try to validate.
+    if clang:
+        return clang
+
+    # Otherwise look in the path.
+    clang = lit.util.which('clang', PATH)
+
+    if not clang:
+        lit.fatal("couldn't find 'clang' program, try setting "
+                  "CLANG in your environment")
+
+    return clang
+
 # When running under valgrind, we mangle '-vg' onto the end of the triple so we
 # can check it with XFAIL and XTARGET.
 if lit.useValgrind:
     config.target_triple += '-vg'
 
-config.clang = llvm_tools_dir + "/clang"
+config.clang = inferClang(config.environment['PATH']).replace('\\', '/')
 if not lit.quiet:
     lit.note('using clang: %r' % config.clang)
 
@@ -101,6 +176,8 @@ if not lit.quiet:
 # the builtin headers. Those are part of even a freestanding environment, but
 # Clang relies on the driver to locate them.
 def getClangBuiltinIncludeDir(clang):
+    # FIXME: Rather than just getting the version, we should have clang print
+    # out its resource dir here in an easy to scrape form.
     cmd = subprocess.Popen([clang, '-print-file-name=include'],
                            stdout=subprocess.PIPE)
     if not cmd.stdout: