From f6d05bbedd482e634507a099e3416fa05cbc0e78 Mon Sep 17 00:00:00 2001
From: Jordan Rose <jordan_rose@apple.com>
Date: Sat, 8 Sep 2012 01:24:49 +0000
Subject: [PATCH] [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
---
 lib/StaticAnalyzer/Core/RegionStore.cpp | 30 ++++++++-----------------
 1 file changed, 9 insertions(+), 21 deletions(-)

diff --git a/lib/StaticAnalyzer/Core/RegionStore.cpp b/lib/StaticAnalyzer/Core/RegionStore.cpp
index 628b790f1f..e0c966e36c 100644
--- a/lib/StaticAnalyzer/Core/RegionStore.cpp
+++ b/lib/StaticAnalyzer/Core/RegionStore.cpp
@@ -1884,7 +1884,6 @@ public:
   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::VisitAddedToCluster(const MemRegion *baseR,
 
 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 @@ void removeDeadBindingsWorker::VisitBinding(SVal V) {
     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 @@ void removeDeadBindingsWorker::VisitBinding(SVal V) {
     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 @@ bool removeDeadBindingsWorker::UpdatePostponed() {
 
   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;
-- 
2.40.0