- Add MemRegion::getMemorySpace()

- Change implementation of MemRegion::hasStackStorage()/hasHeapStorage() to use
  'getMemorySpace()'.  This avoids a double traversal up the region hierarchy
  and is simpler.
- Add MemRegion::hasHeapOrStackStorage() as a slightly more efficient
  alternative to 'hasStackStorage() || hasHeapStorage()'.

llvm-svn: 73977

clang/include/clang/Analysis/PathSensitive/MemRegion.h

@@ -33,7 +33,7 @@ namespace llvm { class raw_ostream; }
 namespace clang {
  
 class MemRegionManager;
-  
+class MemSpaceRegion;  
       
 /// MemRegion - The root abstract class for all memory regions.
 class MemRegion : public llvm::FoldingSetNode {
@@ -68,10 +68,14 @@ public:
   virtual MemRegionManager* getMemRegionManager() const = 0;
 
   std::string getString() const;
+  
+  const MemSpaceRegion *getMemorySpace() const;
     
   bool hasStackStorage() const;
   
   bool hasHeapStorage() const;
+  
+  bool hasHeapOrStackStorage() const;
 
   virtual void print(llvm::raw_ostream& os) const;  
   

clang/lib/Analysis/MemRegion.cpp

@@ -313,46 +313,41 @@ AllocaRegion* MemRegionManager::getAllocaRegion(const Expr* E, unsigned cnt) {
   return getRegion<AllocaRegion>(E, cnt);
 }
 
-bool MemRegion::hasStackStorage() const {
+
-  // Only subregions can have stack storage.
+const MemSpaceRegion *MemRegion::getMemorySpace() const {
+  const MemRegion *R = this;
   const SubRegion* SR = dyn_cast<SubRegion>(this);
-
-  if (!SR)
-    return false;
-
-  MemSpaceRegion* S = getMemRegionManager()->getStackRegion();
   
   while (SR) {
-    const MemRegion *R = SR->getSuperRegion();
+    R = SR->getSuperRegion();
-    if (R == S)
+    SR = dyn_cast<SubRegion>(R);
-      return true;
-    
-    SR = dyn_cast<SubRegion>(R);    
   }
- 
+  
+  return dyn_cast<MemSpaceRegion>(R);
+}
+
+bool MemRegion::hasStackStorage() const {
+  if (const MemSpaceRegion *MS = getMemorySpace())
+    return MS == getMemRegionManager()->getStackRegion();
+
   return false;
 }
 
 bool MemRegion::hasHeapStorage() const {
-  // Only subregions can have stack storage.
+  if (const MemSpaceRegion *MS = getMemorySpace())
-  const SubRegion* SR = dyn_cast<SubRegion>(this);
+    return MS == getMemRegionManager()->getHeapRegion();
-
-  if (!SR)
-    return false;
-
-  MemSpaceRegion* H = getMemRegionManager()->getHeapRegion();
-
-  while (SR) {
-    const MemRegion *R = SR->getSuperRegion();
-    if (R == H)
-      return true;
-
-    SR = dyn_cast<SubRegion>(R);
-  }
 
   return false;
 }
 
+bool MemRegion::hasHeapOrStackStorage() const {
+  if (const MemSpaceRegion *MS = getMemorySpace()) {
+    MemRegionManager *Mgr = getMemRegionManager();
+    return MS == Mgr->getHeapRegion() || MS == Mgr->getStackRegion();
+  }
+  return false;
+}  
+
 //===----------------------------------------------------------------------===//
 // View handling.
 //===----------------------------------------------------------------------===//

clang/lib/Analysis/RegionStore.cpp

@@ -939,7 +939,7 @@ SVal RegionStoreManager::Retrieve(const GRState *state, Loc L, QualType T) {
     }
   }  
 
-  if (R->hasStackStorage() || R->hasHeapStorage()) {
+  if (R->hasHeapOrStackStorage()) {
     // All stack variables are considered to have undefined values
     // upon creation.  All heap allocated blocks are considered to
     // have undefined values as well unless they are explicitly bound