[PATCH] Don't register and de-register all PassRegistrationListeners automatically

[David Blaikie]

I'm with Reid - ship it. (comments describing some optional simplifications, if you like)

================
Comment at: include/llvm/IR/LegacyPassNameParser.h:47
@@ -47,2 +46,3 @@
+  PassNameParser();
   virtual ~PassNameParser();
 
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should we just remove this dtor entirely? (I don't see any reason it needs to be virtual, and it doesn't do anything)

================
Comment at: include/llvm/PassSupport.h:344
@@ -345,8 +343,3 @@
 
-  /// PassRegistrationListener ctor - Add the current object to the list of
-  /// PassRegistrationListeners...
-  PassRegistrationListener();
-
-  /// dtor - Remove object from list of listeners...
-  ///
-  virtual ~PassRegistrationListener();
+  PassRegistrationListener() {}
+  virtual ~PassRegistrationListener() {}
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You can omit this ctor entirely.

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Comment at: include/llvm/PassSupport.h:345
@@ -353,1 +344,3 @@
+  PassRegistrationListener() {}
+  virtual ~PassRegistrationListener() {}
 
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You could make this dtor non-virtual and protected, if you like (not necessary by any means) since these things aren't polymorphically owned/destroyed, by the looks of it.

http://reviews.llvm.org/D4106