1 files changed, 96 insertions, 4 deletions

diff --git a/scripts/gen_compile_commands.py b/scripts/gen_compile_commands.py
index e45f17be8817..92ea0a2ee59e 100755
--- a/scripts/gen_compile_commands.py
+++ b/scripts/gen_compile_commands.py
@@ -12,6 +12,7 @@ import json
 import logging
 import os
 import re
+import subprocess
 
 _DEFAULT_OUTPUT = 'compile_commands.json'
 _DEFAULT_LOG_LEVEL = 'WARNING'
@@ -32,8 +33,9 @@ def parse_arguments():
     Returns:
         log_level: A logging level to filter log output.
         directory: The work directory where the objects were built.
+        ar: Command used for parsing .a archives.
         output: Where to write the compile-commands JSON file.
-        paths: The list of directories to handle to find .cmd files.
+        paths: The list of files/directories to handle to find .cmd files.
     """
     usage = 'Creates a compile_commands.json database from kernel .cmd files'
     parser = argparse.ArgumentParser(description=usage)
@@ -53,12 +55,21 @@ def parse_arguments():
     parser.add_argument('--log_level', choices=_VALID_LOG_LEVELS,
                         default=_DEFAULT_LOG_LEVEL, help=log_level_help)
 
+    ar_help = 'command used for parsing .a archives'
+    parser.add_argument('-a', '--ar', type=str, default='llvm-ar', help=ar_help)
+
+    paths_help = ('directories to search or files to parse '
+                  '(files should be *.o, *.a, or modules.order). '
+                  'If nothing is specified, the current directory is searched')
+    parser.add_argument('paths', type=str, nargs='*', help=paths_help)
+
     args = parser.parse_args()
 
     return (args.log_level,
             os.path.abspath(args.directory),
             args.output,
-            [args.directory])
+            args.ar,
+            args.paths if len(args.paths) > 0 else [args.directory])
 
 
 def cmdfiles_in_dir(directory):
@@ -81,6 +92,73 @@ def cmdfiles_in_dir(directory):
                 yield os.path.join(dirpath, filename)
 
 
+def to_cmdfile(path):
+    """Return the path of .cmd file used for the given build artifact
+
+    Args:
+        Path: file path
+
+    Returns:
+        The path to .cmd file
+    """
+    dir, base = os.path.split(path)
+    return os.path.join(dir, '.' + base + '.cmd')
+
+
+def cmdfiles_for_o(obj):
+    """Generate the iterator of .cmd files associated with the object
+
+    Yield the .cmd file used to build the given object
+
+    Args:
+        obj: The object path
+
+    Yields:
+        The path to .cmd file
+    """
+    yield to_cmdfile(obj)
+
+
+def cmdfiles_for_a(archive, ar):
+    """Generate the iterator of .cmd files associated with the archive.
+
+    Parse the given archive, and yield every .cmd file used to build it.
+
+    Args:
+        archive: The archive to parse
+
+    Yields:
+        The path to every .cmd file found
+    """
+    for obj in subprocess.check_output([ar, '-t', archive]).decode().split():
+        yield to_cmdfile(obj)
+
+
+def cmdfiles_for_modorder(modorder):
+    """Generate the iterator of .cmd files associated with the modules.order.
+
+    Parse the given modules.order, and yield every .cmd file used to build the
+    contained modules.
+
+    Args:
+        modorder: The modules.order file to parse
+
+    Yields:
+        The path to every .cmd file found
+    """
+    with open(modorder) as f:
+        for line in f:
+            ko = line.rstrip()
+            base, ext = os.path.splitext(ko)
+            if ext != '.ko':
+                sys.exit('{}: module path must end with .ko'.format(ko))
+            mod = base + '.mod'
+	    # The first line of *.mod lists the objects that compose the module.
+            with open(mod) as m:
+                for obj in m.readline().split():
+                    yield to_cmdfile(obj)
+
+
 def process_line(root_directory, command_prefix, file_path):
     """Extracts information from a .cmd line and creates an entry from it.
 
@@ -117,7 +195,7 @@ def process_line(root_directory, command_prefix, file_path):
 
 def main():
     """Walks through the directory and finds and parses .cmd files."""
-    log_level, directory, output, paths = parse_arguments()
+    log_level, directory, output, ar, paths = parse_arguments()
 
     level = getattr(logging, log_level)
     logging.basicConfig(format='%(levelname)s: %(message)s', level=level)
@@ -127,7 +205,21 @@ def main():
     compile_commands = []
 
     for path in paths:
-        cmdfiles = cmdfiles_in_dir(path)
+        # If 'path' is a directory, handle all .cmd files under it.
+        # Otherwise, handle .cmd files associated with the file.
+        # Most of built-in objects are linked via archives (built-in.a or lib.a)
+        # but some objects are linked to vmlinux directly.
+        # Modules are listed in modules.order.
+        if os.path.isdir(path):
+            cmdfiles = cmdfiles_in_dir(path)
+        elif path.endswith('.o'):
+            cmdfiles = cmdfiles_for_o(path)
+        elif path.endswith('.a'):
+            cmdfiles = cmdfiles_for_a(path, ar)
+        elif path.endswith('modules.order'):
+            cmdfiles = cmdfiles_for_modorder(path)
+        else:
+            sys.exit('{}: unknown file type'.format(path))
 
         for cmdfile in cmdfiles:
             with open(cmdfile, 'rt') as f: