[analyzer] Symbolic regions are live if any subregions are live.

RegionStoreManager was only treating a SymbolicRegion's symbel as live
if there was a binding referring to the region itself.

No test case because constraints are currently not being cleaned out
of the constraint manager at all (even if the symbol is legitimately dead).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@163443 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Core/RegionStore.cpp b/lib/StaticAnalyzer/Core/RegionStore.cpp
index 628b790..e0c966e 100644
--- a/lib/StaticAnalyzer/Core/RegionStore.cpp
+++ b/lib/StaticAnalyzer/Core/RegionStore.cpp
@@ -1884,7 +1884,6 @@
   void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C);
   void VisitCluster(const MemRegion *baseR, const ClusterBindings &C);
 
-  void VisitBindingKey(BindingKey K);
   bool UpdatePostponed();
   void VisitBinding(SVal V);
 };
@@ -1926,10 +1925,13 @@
 
 void removeDeadBindingsWorker::VisitCluster(const MemRegion *baseR,
                                             const ClusterBindings &C) {
-  for (ClusterBindings::iterator I = C.begin(), E = C.end(); I != E; ++I) {
-    VisitBindingKey(I.getKey());
+  // Mark the symbol for any SymbolicRegion with live bindings as live itself.
+  // This means we should continue to track that symbol.
+  if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(baseR))
+    SymReaper.markLive(SymR->getSymbol());
+
+  for (ClusterBindings::iterator I = C.begin(), E = C.end(); I != E; ++I)
     VisitBinding(I.getData());
-  }
 }
 
 void removeDeadBindingsWorker::VisitBinding(SVal V) {
@@ -1966,8 +1968,8 @@
     if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(R)) {
       BlockDataRegion::referenced_vars_iterator I = BR->referenced_vars_begin(),
                                                 E = BR->referenced_vars_end();
-        for ( ; I != E; ++I)
-          AddToWorkList(I.getCapturedRegion());
+      for ( ; I != E; ++I)
+        AddToWorkList(I.getCapturedRegion());
     }
   }
     
@@ -1978,20 +1980,6 @@
     SymReaper.markLive(*SI);
 }
 
-void removeDeadBindingsWorker::VisitBindingKey(BindingKey K) {
-  const MemRegion *R = K.getRegion();
-
-  // Mark this region "live" by adding it to the worklist.  This will cause
-  // use to visit all regions in the cluster (if we haven't visited them
-  // already).
-  if (AddToWorkList(R)) {
-    // Mark the symbol for any live SymbolicRegion as "live".  This means we
-    // should continue to track that symbol.
-    if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(R))
-      SymReaper.markLive(SymR->getSymbol());
-  }
-}
-
 bool removeDeadBindingsWorker::UpdatePostponed() {
   // See if any postponed SymbolicRegions are actually live now, after
   // having done a scan.
@@ -1999,7 +1987,7 @@
 
   for (SmallVectorImpl<const SymbolicRegion*>::iterator
         I = Postponed.begin(), E = Postponed.end() ; I != E ; ++I) {
-    if (const SymbolicRegion *SR = cast_or_null<SymbolicRegion>(*I)) {
+    if (const SymbolicRegion *SR = *I) {
       if (SymReaper.isLive(SR->getSymbol())) {
         changed |= AddToWorkList(SR);
         *I = NULL;