Add a new pass AddReadAttrs which works out which functions

can get the readnone/readonly attributes, and gives them it.
The plan is to remove markmodref (which did the same thing
by querying GlobalsModRef) and delete the analogous
functionality from GlobalsModRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56341 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/IPO.h

@@ -188,6 +188,12 @@ ModulePass *createStripDeadPrototypesPass();
 ///
 ModulePass* createPartialSpecializationPass();
 
+//===----------------------------------------------------------------------===//
+/// createAddReadAttrsPass - This pass discovers functions that do not access
+/// memory, or only read memory, and gives them the readnone/readonly attribute.
+///
+Pass* createAddReadAttrsPass();
+
 } // End llvm namespace
 
 #endif