Index: utils/opt-viewer/opt-stats.py
===================================================================
--- utils/opt-viewer/opt-stats.py
+++ utils/opt-viewer/opt-stats.py
@@ -38,7 +38,7 @@
 
     bypass = defaultdict(int)
     byname = defaultdict(int)
-    for r in all_remarks.itervalues():
+    for r in iter(all_remarks.values()):
         bypass[r.Pass] += 1
         byname[r.Pass + "/" + r.Name] += 1
 
Index: utils/opt-viewer/optrecord.py
===================================================================
--- utils/opt-viewer/optrecord.py
+++ utils/opt-viewer/optrecord.py
@@ -117,7 +117,7 @@
     def key(self):
         k = (self.__class__, self.PassWithDiffPrefix, self.Name, self.File, self.Line, self.Column, self.Function)
         for arg in self.Args:
-            for (key, value) in arg.iteritems():
+            for (key, value) in iter(arg.items()):
                 if type(value) is dict:
                     value = tuple(value.items())
                 k += (key, value)
@@ -196,8 +196,8 @@
     max_hotness = max(entry[0] for entry in remarks)
 
     def merge_file_remarks(file_remarks_job, all_remarks, merged):
-        for filename, d in file_remarks_job.iteritems():
-            for line, remarks in d.iteritems():
+        for filename, d in iter(file_remarks_job.items()):
+            for line, remarks in iter(d.items()):
                 for remark in remarks:
                     # Bring max_hotness into the remarks so that
                     # RelativeHotness does not depend on an external global.