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git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112414 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/AggExprVisitor.cpp b/lib/Checker/AggExprVisitor.cpp
index e9c0b1e..6d472f4 100644
--- a/lib/Checker/AggExprVisitor.cpp
+++ b/lib/Checker/AggExprVisitor.cpp
@@ -18,6 +18,13 @@
using namespace clang;
namespace {
+/// AggExprVisitor is designed after AggExprEmitter of the CodeGen module. It
+/// is used for evaluating exprs of C++ object type. Evaluating such exprs
+/// requires a destination pointer pointing to the object being evaluated
+/// into. Passing such a pointer around would pollute the Visit* interface of
+/// GRExprEngine. AggExprVisitor encapsulates code that goes through various
+/// cast and construct exprs (and others), and at the final point, dispatches
+/// back to the GRExprEngine to let the real evaluation logic happen.
class AggExprVisitor : public StmtVisitor<AggExprVisitor> {
SVal DestPtr;
ExplodedNode *Pred;