jobfile: Add support for dictionaries as jobfile options.

If the same dictionary option is seen in several options, those
dictionaries are composed.  If you define the same dictionary key in
multiple options, the system flags an error.
Also, clean up the jobfile code so that it is more debuggable.

src/python/m5/util/jobfile.py

@@ -28,8 +28,8 @@
 
 import sys
 
-from attrdict import attrdict, optiondict
-from misc import crossproduct, flatten
+from attrdict import optiondict
+from misc import crossproduct
 
 class Data(object):
     def __init__(self, name, desc, **kwargs):
@@ -41,9 +41,29 @@ class Data(object):
         if not isinstance(obj, Data):
             raise AttributeError, "can only update from Data object"
 
-        for k,v in obj.__dict__.iteritems():
-            if not k.startswith('_'):
-                self.__dict__[k] = v
+        for key,val in obj.__dict__.iteritems():
+            if key.startswith('_') or key in ('name', 'desc'):
+                continue
+
+            if key not in self.__dict__:
+                self.__dict__[key] = val
+                continue
+
+            if not isinstance(val, dict):
+                if self.__dict__[key] == val:
+                    continue
+
+                raise AttributeError, \
+                      "%s specified more than once old: %s new: %s" % \
+                      (key, self.__dict__[key], val)
+
+            d = self.__dict__[key]
+            for k,v in val.iteritems():
+                if k in d:
+                    raise AttributeError, \
+                          "%s specified more than once in %s" % (k, key)
+                d[k] = v
+
         if hasattr(self, 'system') and hasattr(obj, 'system'):
             if self.system != obj.system:
                 raise AttributeError, \
@@ -93,6 +113,14 @@ class Data(object):
             result[key] = self[key]
         return result
 
+    def __repr__(self):
+        d = {}
+        for key,value in self.__dict__.iteritems():
+            if not key.startswith('_'):
+                d[key] = value
+
+        return "<%s: %s>" % (type(self).__name__, d)
+
     def __str__(self):
         return self.name
 
@@ -391,18 +419,12 @@ def JobFile(jobfile):
     execfile(filename, data)
     if 'conf' not in data:
         raise ImportError, 'cannot import name conf from %s' % jobfile
-    conf = data['conf']
-    import jobfile
-    if not isinstance(conf, Configuration):
-        raise AttributeError, \
-              'conf in jobfile: %s (%s) is not type %s' % \
-              (jobfile, type(conf), Configuration)
-    return conf
+    return data['conf']
 
 def main(conf=None):
-    import sys
-
-    usage = 'Usage: %s [-b] [-c] [-v] <jobfile>' % sys.argv[0]
+    usage = 'Usage: %s [-b] [-c] [-v]' % sys.argv[0]
+    if conf is None:
+        usage += ' <jobfile>'
 
     try:
         import getopt