python: add a sorted dictionary class

It would be nice if python had a tree class that would do this for real,
but since we don't, we'll just keep a sorted list of keys and update
it on demand.

src/python/SConscript

@@ -58,6 +58,7 @@ PySource('m5.util', 'm5/util/jobfile.py')
 PySource('m5.util', 'm5/util/multidict.py')
 PySource('m5.util', 'm5/util/orderdict.py')
 PySource('m5.util', 'm5/util/smartdict.py')
+PySource('m5.util', 'm5/util/sorteddict.py')
 
 SwigSource('m5.internal', 'swig/core.i')
 SwigSource('m5.internal', 'swig/debug.i')

src/python/m5/util/__init__.py

@@ -39,6 +39,7 @@ from code_formatter import code_formatter
 from multidict import multidict
 from orderdict import orderdict
 from smartdict import SmartDict
+from sorteddict import SortedDict
 
 # define this here so we can use it right away if necessary
 def errorURL(prefix, s):

src/python/m5/util/sorteddict.py

@@ -0,0 +1,159 @@
+# Copyright (c) 2006-2009 Nathan Binkert <nate@binkert.org>
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+class SortedDict(dict):
+    def _get_sorted(self):
+        return getattr(self, '_sorted', sorted)
+    def _set_sorted(self, val):
+        self._sorted = val
+        self._del_keys()
+    sorted = property(_get_sorted, _set_sorted)
+
+    @property
+    def _keys(self):
+        try:
+            return self._sorted_keys
+        except AttributeError:
+            _sorted_keys = self.sorted(dict.iterkeys(self))
+            self._sorted_keys = _sorted_keys
+            return _sorted_keys
+
+    def _del_keys(self):
+        try:
+            del self._sorted_keys
+        except AttributeError:
+            pass
+
+    def __repr__(self):
+        return 'SortedDict({%s})' % ', '.join('%r: %r' % item
+                                              for item in self.iteritems())
+    def __setitem__(self, key, item):
+        dict.__setitem__(self, key, item)
+        self._del_keys()
+
+    def __delitem__(self, key):
+        dict.__delitem__(self, key)
+        self._del_keys()
+
+    def clear(self):
+        self.data.clear()
+        self._del_keys()
+
+    def copy(self):
+        t = type(self)
+        return t(self)
+
+    def keys(self):
+        return self._keys[:]
+
+    def values(self):
+        return list(self.itervalues())
+
+    def items(self):
+        return list(self.iteritems())
+
+    def iterkeys(self):
+        return iter(self._keys)
+
+    def itervalues(self):
+        for k in self._keys:
+            yield self[k]
+
+    def iteritems(self):
+        for k in self._keys:
+            yield k, self[k]
+
+    def update(self, *args, **kwargs):
+        dict.update(self, *args, **kwargs)
+        self._del_keys()
+
+    def setdefault(self, key, _failobj=None):
+        try:
+            return self[key]
+        except KeyError:
+            self[key] = _failobj
+
+    def pop(self, key, *args):
+        try:
+            dict.pop(self, key)
+            self._del_keys()
+        except KeyError:
+            if not args:
+                raise
+            return args[0]
+
+    def popitem(self):
+        try:
+            key = self._keys[0]
+            self._del_keys()
+        except IndexError:
+            raise KeyError('popitem(): dictionary is empty')
+        else:
+            return key, dict.pop(self, key)
+
+    @classmethod
+    def fromkeys(cls, seq, value=None):
+        d = cls()
+        for key in seq:
+            d[key] = value
+        return d
+
+if __name__ == '__main__':
+    def display(d):
+        print d
+        print d.keys()
+        print list(d.iterkeys())
+        print d.values()
+        print list(d.itervalues())
+        print d.items()
+        print list(d.iteritems())
+
+    d = SortedDict(x=24,e=5,j=4,b=2,z=26,d=4)
+    display(d)
+
+    print 'popitem', d.popitem()
+    display(d)
+
+    print 'pop j'
+    d.pop('j')
+    display(d)
+
+    d.setdefault('a', 1)
+    d.setdefault('g', 7)
+    d.setdefault('_')
+    display(d)
+
+    d.update({'b' : 2, 'h' : 8})
+    display(d)
+
+    del d['x']
+    display(d)
+    d['y'] = 26
+    display(d)
+
+    print `d`
+
+    print d.copy()