[analyzer] Add missing pre-post-statement callbacks for OffsetOfExpr.

This expression may or may not be evaluated in compile time, so tracking the
result symbol is of potential interest. However, run-time offsetof is not yet
supported by the analyzer, so for now this callback is only there to assist
future implementation.

Patch by Henry Wong!

Differential Revision: https://reviews.llvm.org/D42300

llvm-svn: 324790

2 files changed, 22 insertions, 3 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/AnalysisOrderChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/AnalysisOrderChecker.cpp
index dc9dd5bd06d..e4cdc500de6 100644
--- a/clang/lib/StaticAnalyzer/Checkers/AnalysisOrderChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/AnalysisOrderChecker.cpp
@@ -33,6 +33,8 @@ class AnalysisOrderChecker
                      check::PostStmt<ArraySubscriptExpr>,
                      check::PreStmt<CXXNewExpr>,
                      check::PostStmt<CXXNewExpr>,
+                     check::PreStmt<OffsetOfExpr>,
+                     check::PostStmt<OffsetOfExpr>,
                      check::PreCall,
                      check::PostCall,
                      check::NewAllocator,
@@ -91,6 +93,16 @@ public:
       llvm::errs() << "PostStmt<CXXNewExpr>\n";
   }
 
+  void checkPreStmt(const OffsetOfExpr *OOE, CheckerContext &C) const {
+    if (isCallbackEnabled(C, "PreStmtOffsetOfExpr"))
+      llvm::errs() << "PreStmt<OffsetOfExpr>\n";
+  }
+
+  void checkPostStmt(const OffsetOfExpr *OOE, CheckerContext &C) const {
+    if (isCallbackEnabled(C, "PostStmtOffsetOfExpr"))
+      llvm::errs() << "PostStmt<OffsetOfExpr>\n";
+  }
+
   void checkPreCall(const CallEvent &Call, CheckerContext &C) const {
     if (isCallbackEnabled(C, "PreCall")) {
       llvm::errs() << "PreCall";
diff --git a/clang/lib/StaticAnalyzer/Core/ExprEngine.cpp b/clang/lib/StaticAnalyzer/Core/ExprEngine.cpp
index fef7116d905..210cea6818e 100644
--- a/clang/lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -1543,12 +1543,19 @@ void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred,
       Bldr.addNodes(Dst);
       break;
 
-    case Stmt::OffsetOfExprClass:
+    case Stmt::OffsetOfExprClass: {
       Bldr.takeNodes(Pred);
-      VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst);
+      ExplodedNodeSet PreVisit;
+      getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this);
+
+      ExplodedNodeSet PostVisit;
+      for (ExplodedNode *Node : PreVisit)
+        VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Node, PostVisit);
+
+      getCheckerManager().runCheckersForPostStmt(Dst, PostVisit, S, *this);
       Bldr.addNodes(Dst);
       break;
-
+    }
     case Stmt::UnaryExprOrTypeTraitExprClass:
       Bldr.takeNodes(Pred);
       VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S),