[analyzer] Extract ControlDependencyHandler

[vsavchenko]

Rebase

[NoQ]

Great!

clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp

2114

/*comment=*/ pls 🥺👉👈

[vsavchenko]

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clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp

PathDiagnosticPieceRef handle(StoreInfo SI, BugReporterContext &BRC,
 
     if (!L.isValid() || !L.asLocation().isValid())
       return nullptr;
 
     return std::make_shared<PathDiagnosticEventPiece>(L, OS.str());
   }
 };
 
-class DefaultExpressionHandler final : public ExpressionHandler {
+class ControlDependencyHandler final : public ExpressionHandler {
 public:
   using ExpressionHandler::ExpressionHandler;
 
   Tracker::Result handle(const Expr *Inner, const ExplodedNode *InputNode,
                          const ExplodedNode *LVNode,
                          TrackingOptions Opts) override {
-    ProgramStateRef LVState = LVNode->getState();
-    const StackFrameContext *SFC = LVNode->getStackFrame();
     PathSensitiveBugReport &Report = getParentTracker().getReport();
-    Tracker::Result Result;
 
     // We only track expressions if we believe that they are important. Chances
     // are good that control dependencies to the tracking point are also
     // important because of this, let's explain why we believe control reached
     // this point.
     // TODO: Shouldn't we track control dependencies of every bug location,
     // rather than only tracked expressions?
-    if (LVState->getAnalysisManager()
+    if (LVNode->getState()
+            ->getAnalysisManager()
             .getAnalyzerOptions()
             .ShouldTrackConditions) {
       Report.addVisitor<TrackControlDependencyCondBRVisitor>(
           &getParentTracker(), InputNode);
-      Result.FoundSomethingToTrack = true;
+      return {true};
     }
 
+    return {};
+  }
+};
+
+class DefaultExpressionHandler final : public ExpressionHandler {
+public:
+  using ExpressionHandler::ExpressionHandler;
+
+  Tracker::Result handle(const Expr *Inner, const ExplodedNode *InputNode,
+                         const ExplodedNode *LVNode,
+                         TrackingOptions Opts) override {
+    ProgramStateRef LVState = LVNode->getState();
+    const StackFrameContext *SFC = LVNode->getStackFrame();
+    PathSensitiveBugReport &Report = getParentTracker().getReport();
+    Tracker::Result Result;
+
     // The message send could be nil due to the receiver being nil.
     // At this point in the path, the receiver should be live since we are at
     // the message send expr. If it is nil, start tracking it.
     if (const Expr *Receiver =
             NilReceiverBRVisitor::getNilReceiver(Inner, LVNode))
       Result.combineWith(getParentTracker().track(Receiver, LVNode, Opts));
 
     // Track the index if this is an array subscript.
Tracker::Result handle(const Expr *E, const ExplodedNode *InputNode,
     }
 
     return CombinedResult;
   }
 };
 
 Tracker::Tracker(PathSensitiveBugReport &Report) : Report(Report) {
   // Default expression handlers.
-  addHighPriorityHandler<DefaultExpressionHandler>();
+  addLowPriorityHandler<ControlDependencyHandler>();
+  addLowPriorityHandler<DefaultExpressionHandler>();
   addLowPriorityHandler<RValueHandler>();
   // Default store handlers.
   addHighPriorityHandler<DefaultStoreHandler>();
 }
 
 Tracker::Result Tracker::track(const Expr *E, const ExplodedNode *N,
                                TrackingOptions Opts) {
   if (!E || !N)