Better handling of latency/frequency parameter types

python/m5/config.py:
    Addr is slightly different from memory size in that Addr
    will take non strings.
    Deal with the fact that the convert.toFoo functions only accept
    strings.
    Add RootFrequency as a special type for the Root.frequency
    parameter which is not scaled.
    Add ClockPeriod parameter type.
python/m5/convert.py:
    Be more strict about what's allowed.
    Only accept strings as inputs for these conversion functions.
    If the user wants to accept something else, they need to deal
    with the failure and convert other types on their own.
python/m5/objects/Bus.mpy:
    Use the new ClockPeriod parameter type
python/m5/objects/Root.mpy:
    Can't use integers for frequency anymore
python/m5/smartdict.py:
    rename SmartDict.Proxy to just Variable.  Create a new class
    UndefinedVariable that is returned when the user tries to get
    a variable that is not in the dict.  Undefined variable evaluates
    to false, and will cause an error elsewhere.

--HG--
extra : convert_revision : 1d55246fd1af65106f102396234827d6401ef9ce

1 files changed, 87 insertions, 69 deletions

diff --git a/python/m5/smartdict.py b/python/m5/smartdict.py
index 0dbcc50b0..a2661c279 100644
--- a/python/m5/smartdict.py
+++ b/python/m5/smartdict.py
@@ -16,93 +16,111 @@
 
 from convert import *
 
+class Variable(str):
+    """Intelligent proxy class for SmartDict.  Variable will use the
+    various convert functions to attempt to convert values to useable
+    types"""
+    def __int__(self):
+        return toInteger(str(self))
+    def __long__(self):
+        return toLong(str(self))
+    def __float__(self):
+        return toFloat(str(self))
+    def __nonzero__(self):
+        return toBool(str(self))
+    def convert(self, other):
+        t = type(other)
+        if t == bool:
+            return bool(self)
+        if t == int:
+            return int(self)
+        if t == long:
+            return long(self)
+        if t == float:
+            return float(self)
+        return str(self)
+    def __lt__(self, other):
+        return self.convert(other) < other
+    def __le__(self, other):
+        return self.convert(other) <= other
+    def __eq__(self, other):
+        return self.convert(other) == other
+    def __ne__(self, other):
+        return self.convert(other) != other
+    def __gt__(self, other):
+        return self.convert(other) > other
+    def __ge__(self, other):
+        return self.convert(other) >= other
+
+    def __add__(self, other):
+        return self.convert(other) + other
+    def __sub__(self, other):
+        return self.convert(other) - other
+    def __mul__(self, other):
+        return self.convert(other) * other
+    def __div__(self, other):
+        return self.convert(other) / other
+    def __truediv__(self, other):
+        return self.convert(other) / other
+
+    def __radd__(self, other):
+        return other + self.convert(other)
+    def __rsub__(self, other):
+        return other - self.convert(other)
+    def __rmul__(self, other):
+        return other * self.convert(other)
+    def __rdiv__(self, other):
+        return other / self.convert(other)
+    def __rtruediv__(self, other):
+        return other / self.convert(other)
+
+class UndefinedVariable(object):
+    """Placeholder class to represent undefined variables.  Will
+    generally cause an exception whenever it is used, but evaluates to
+    zero for boolean truth testing such as in an if statement"""
+    def __nonzero__(self):
+        return False
+
 class SmartDict(dict):
+    """Dictionary class that holds strings, but intelligently converts
+    those strings to other types depending on their usage"""
 
-    class Proxy(str):
-        def __int__(self):
-            return int(toInteger(str(self)))
-        def __long__(self):
-            return long(toInteger(str(self)))
-        def __float__(self):
-            return float(toInteger(str(self)))
-        def __nonzero__(self):
-            return toBool(str(self))
-        def convert(self, other):
-            t = type(other)
-            if t == bool:
-                return bool(self)
-            if t == int:
-                return int(self)
-            if t == long:
-                return long(self)
-            if t == float:
-                return float(self)
-            return str(self)
-        def __lt__(self, other):
-            return self.convert(other) < other
-        def __le__(self, other):
-            return self.convert(other) <= other
-        def __eq__(self, other):
-            return self.convert(other) == other
-        def __ne__(self, other):
-            return self.convert(other) != other
-        def __gt__(self, other):
-            return self.convert(other) > other
-        def __ge__(self, other):
-            return self.convert(other) >= other
-
-        def __add__(self, other):
-            return self.convert(other) + other
-        def __sub__(self, other):
-            return self.convert(other) - other
-        def __mul__(self, other):
-            return self.convert(other) * other
-        def __div__(self, other):
-            return self.convert(other) / other
-        def __truediv__(self, other):
-            return self.convert(other) / other
-
-        def __radd__(self, other):
-            return other + self.convert(other)
-        def __rsub__(self, other):
-            return other - self.convert(other)
-        def __rmul__(self, other):
-            return other * self.convert(other)
-        def __rdiv__(self, other):
-            return other / self.convert(other)
-        def __rtruediv__(self, other):
-            return other / self.convert(other)
-
-
-    # __getitem__ uses dict.get() to return 'False' if the key is not
-    # found (rather than raising KeyError).  Note that this does *not*
-    # set the key's value to 'False' in the dict, so that even after
-    # we call env['foo'] we still get a meaningful answer from "'foo'
-    # in env" (which calls dict.__contains__, which we do not
-    # override).
     def __getitem__(self, key):
-        return self.Proxy(dict.get(self, key, 'False'))
+        """returns a Variable proxy if the values exists in the database and
+        returns an UndefinedVariable otherwise"""
+
+        if key in self:
+            return Variable(dict.get(self, key))
+        else:
+            # Note that this does *not* change the contents of the dict,
+            # so that even after we call env['foo'] we still get a
+            # meaningful answer from "'foo' in env" (which
+            # calls dict.__contains__, which we do not override).
+            return UndefinedVariable()
 
     def __setitem__(self, key, item):
+        """intercept the setting of any variable so that we always
+        store strings in the dict"""
         dict.__setitem__(self, key, str(item))
 
     def values(self):
-        return [ self.Proxy(v) for v in dict.values(self) ]
+        return [ Variable(v) for v in dict.values(self) ]
 
     def itervalues(self):
         for value in dict.itervalues(self):
-            yield self.Proxy(value)
+            yield Variable(value)
 
     def items(self):
-        return [ (k, self.Proxy(v)) for k,v in dict.items(self) ]
+        return [ (k, Variable(v)) for k,v in dict.items(self) ]
 
     def iteritems(self):
         for key,value in dict.iteritems(self):
-            yield key, self.Proxy(value)
+            yield key, Variable(value)
 
     def get(self, key, default='False'):
-        return self.Proxy(dict.get(self, key, str(default)))
+        return Variable(dict.get(self, key, str(default)))
 
     def setdefault(self, key, default='False'):
-        return self.Proxy(dict.setdefault(self, key, str(default)))
+        return Variable(dict.setdefault(self, key, str(default)))
 
+__all__ = [ 'SmartDict' ]