More doxygen/documentation cleanups.

This reduces the number of warnings generated by Doxygen by about 100
(roughly 10%).  Issues addressed:
(1) Primarily, backslash-escaped "@foo" and "#bah" in Doxygen comments
when they're not supposed to be Doxygen commands or links, and
similarly for "<baz>" when it's not intended as as HTML tag;
(2) Changed some \t commands (which don't exist) to \c ("to refer to a
word of code", as the Doxygen manual says);
(3) \precondition becomes \pre;
(4) When touching comments, deleted a couple of spurious spaces in them;
(5) Changed some \n and \r to \\n and \\r;
(6) Fixed one tiny typo: #pragms -> #pragma.

This patch touches documentation/comments only.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158422 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGObjCGNU.cpp b/lib/CodeGen/CGObjCGNU.cpp
index e3ae237..e593511 100644
--- a/lib/CodeGen/CGObjCGNU.cpp
+++ b/lib/CodeGen/CGObjCGNU.cpp
@@ -292,8 +292,8 @@
 protected:
   /// Function used for throwing Objective-C exceptions.
   LazyRuntimeFunction ExceptionThrowFn;
-  /// Function used for rethrowing exceptions, used at the end of @finally or
-  /// @synchronize blocks.
+  /// Function used for rethrowing exceptions, used at the end of \@finally or
+  /// \@synchronize blocks.
   LazyRuntimeFunction ExceptionReThrowFn;
   /// Function called when entering a catch function.  This is required for
   /// differentiating Objective-C exceptions and foreign exceptions.
@@ -301,9 +301,9 @@
   /// Function called when exiting from a catch block.  Used to do exception
   /// cleanup.
   LazyRuntimeFunction ExitCatchFn;
-  /// Function called when entering an @synchronize block.  Acquires the lock.
+  /// Function called when entering an \@synchronize block.  Acquires the lock.
   LazyRuntimeFunction SyncEnterFn;
-  /// Function called when exiting an @synchronize block.  Releases the lock.
+  /// Function called when exiting an \@synchronize block.  Releases the lock.
   LazyRuntimeFunction SyncExitFn;
 
 private:
@@ -350,7 +350,7 @@
       ArrayRef<Selector> MethodSels,
       ArrayRef<llvm::Constant *> MethodTypes,
       bool isClassMethodList);
-  /// Emits an empty protocol.  This is used for @protocol() where no protocol
+  /// Emits an empty protocol.  This is used for \@protocol() where no protocol
   /// is found.  The runtime will (hopefully) fix up the pointer to refer to the
   /// real protocol.
   llvm::Constant *GenerateEmptyProtocol(const std::string &ProtocolName);