[NFC] fix trivial typos in comments and documents

"in in" -> "in", "on on" -> "on" etc.

llvm-svn: 323508
diff --git a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h
index 7962b76..28bceab 100644
--- a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h
+++ b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h
@@ -112,7 +112,7 @@
 
   virtual void emitTypeInfos(unsigned TTypeEncoding);
 
-  // Helpers for for identifying what kind of clause an EH typeid or selector
+  // Helpers for identifying what kind of clause an EH typeid or selector
   // corresponds to. Negative selectors are for filter clauses, the zero
   // selector is for cleanups, and positive selectors are for catch clauses.
   static bool isFilterEHSelector(int Selector) { return Selector < 0; }