- Add capability to auto-generate Param structs from

.mpy SimObject descriptions.  Structs are defined
in simobj/param/ObjectName.hh.
- Move compile-time python params (from CPPDEFINES) to
separate dict from run-time params (from os.environ).
The former are needed to generate proper param structs.
This also helps prevent users from messing things up
by setting the wrong environment vars (which could have
overridden compile-time settings in the old system).
- Other misc cleanup of m5 python package.

SConscript:
    Include simobj/SConscript
build/SConstruct:
    Fix type in comment
python/SConscript:
    Move CPPDEFINES dict-generating code to m5scons.flatten_defines
python/m5/__init__.py:
    - Generate a build_env SmartDict here to hold compile-time
    params (passed in via __main__.m5_build_env).
    - Move panic and env here from config.py.
python/m5/config.py:
    Move panic, env to top level (m5/__init__.py)
python/m5/objects/BaseCPU.mpy:
    Use build_env instead of env for compile-time params
python/m5/smartdict.py:
    Add some comments.
sim/sim_object.hh:
    Include auto-generated Param struct.  Not used yet,
    just here as proof of concept.
test/genini.py:
    Put -E arguments in build_env as well as os.environ

--HG--
extra : convert_revision : cf6f4a2565b230c495b33b18612d6030988adac5

1 files changed, 20 insertions, 3 deletions

diff --git a/python/m5/smartdict.py b/python/m5/smartdict.py
index e282bc07b..4ea8210d3 100644
--- a/python/m5/smartdict.py
+++ b/python/m5/smartdict.py
@@ -1,6 +1,23 @@
+# The SmartDict class fixes a couple of issues with using the content
+# of os.environ or similar dicts of strings as Python variables:
+#
+# 1) Undefined variables should return False rather than raising KeyError.
+#
+# 2) String values of 'False', '0', etc., should evaluate to False
+#    (not just the empty string).
+#
+# #1 is solved by overriding __getitem__, and #2 is solved by using a
+# proxy class for values and overriding __nonzero__ on the proxy.
+# Everything else is just to (a) make proxies behave like normal
+# values otherwise, (b) make sure any dict operation returns a proxy
+# rather than a normal value, and (c) coerce values written to the
+# dict to be strings.
+
+
 from convert import *
 
 class SmartDict(dict):
+
     class Proxy(str):
         def __int__(self):
             return int(to_integer(str(self)))
@@ -58,7 +75,7 @@ class SmartDict(dict):
 
 
     def __getitem__(self, key):
-        return self.Proxy(dict.__getitem__(self, key))
+        return self.Proxy(dict.get(self, key, 'False'))
 
     def __setitem__(self, key, item):
         dict.__setitem__(self, key, str(item))
@@ -77,9 +94,9 @@ class SmartDict(dict):
         for key,value in dict.iteritems(self):
             yield key, self.Proxy(value)
 
-    def get(self, key, default=''):
+    def get(self, key, default='False'):
         return self.Proxy(dict.get(self, key, str(default)))
 
-    def setdefault(self, key, default=''):
+    def setdefault(self, key, default='False'):
         return self.Proxy(dict.setdefault(self, key, str(default)))