add comments.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@106617 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Checker/OSAtomicChecker.cpp b/lib/Checker/OSAtomicChecker.cpp
index 44dcdd4230713bffcd98f303074b93d7909bc5ba..1ea1bd98d6dc2089cbf96bba86d898dfe3f35465 100644 (file)
--- a/lib/Checker/OSAtomicChecker.cpp
+++ b/lib/Checker/OSAtomicChecker.cpp
@@ -102,7 +102,11 @@ bool OSAtomicChecker::EvalOSAtomicCompareAndSwap(CheckerContext &C,
   SVal location = state->getSVal(theValueExpr);
   // Here we should use the value type of the region as the load type, because
   // we are simulating the semantics of the function, not the semantics of 
-  // passing argument.
+  // passing argument. So the type of theValue expr is not we are loading.
+  // But usually the type of the varregion is not the type we want either,
+  // we still need to do a CastRetrievedVal in store manager. So actually this
+  // LoadTy specifying can be omitted. But we put it here to emphasize the 
+  // semantics.
   QualType LoadTy;
   if (const TypedRegion *TR =
       dyn_cast_or_null<TypedRegion>(location.getAsRegion())) {