Remove 'SelfRegion' field from both BasicStoreManager and RegionStoreManager.

SelfRegion represented the object bound to 'self' (when analyzing Objective-C
methods) upon entry to a method. Having this region stored on the side ignores
the current stack frame that we might be analyzing (among other things), and is
a problem for interprocedural analysis.

For RegionStoreManager, the value for SelfRegion is just lazily created.

For BasicStoreManager, the value for SelfRegion is bound eagerly to 'self', but
no explicit tracking of SelfRegion on the side is made.

As part of this change, remove the restriction in BasicStoreManager that we only
track ivars for 'self'. This shouldn't actually change anything in terms of
precision, and simplifies the logic.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@79694 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 16 insertions, 31 deletions

diff --git a/lib/Analysis/BasicStore.cpp b/lib/Analysis/BasicStore.cpp
index 65efb66148..50b90f5813 100644
--- a/lib/Analysis/BasicStore.cpp
+++ b/lib/Analysis/BasicStore.cpp
@@ -36,11 +36,9 @@ public:
   
 class VISIBILITY_HIDDEN BasicStoreManager : public StoreManager {
   BindingsTy::Factory VBFactory;
-  const MemRegion* SelfRegion;
-  
 public:
   BasicStoreManager(GRStateManager& mgr)
-    : StoreManager(mgr), VBFactory(mgr.getAllocator()), SelfRegion(0) {}
+    : StoreManager(mgr), VBFactory(mgr.getAllocator()) {}
   
   ~BasicStoreManager() {}
 
@@ -58,7 +56,8 @@ public:
     return state->makeWithStore(BindInternal(state->getStore(), L, V));
   }
 
-  Store scanForIvars(Stmt *B, const Decl* SelfDecl, Store St);
+  Store scanForIvars(Stmt *B, const Decl* SelfDecl,
+                     const MemRegion *SelfRegion, Store St);
   
   Store BindInternal(Store St, Loc loc, SVal V);  
   Store Remove(Store St, Loc loc);
@@ -88,11 +87,6 @@ public:
   /// ArrayToPointer - Used by GRExprEngine::VistCast to handle implicit
   ///  conversions between arrays and pointers.
   SVal ArrayToPointer(Loc Array) { return Array; }
-
-  /// getSelfRegion - Returns the region for the 'self' (Objective-C) or
-  ///  'this' object (C++).  When used when analyzing a normal function this
-  ///  method returns NULL.
-  const MemRegion* getSelfRegion(Store) { return SelfRegion; }
     
   /// RemoveDeadBindings - Scans a BasicStore of 'state' for dead values.
   ///  It updatees the GRState object in place with the values removed.
@@ -148,7 +142,8 @@ SVal BasicStoreManager::getLValueCompoundLiteral(const GRState *state,
   return ValMgr.makeLoc(MRMgr.getCompoundLiteralRegion(CL));
 }
 
-SVal BasicStoreManager::getLValueIvar(const GRState *state, const ObjCIvarDecl* D,
+SVal BasicStoreManager::getLValueIvar(const GRState *state,
+                                      const ObjCIvarDecl* D,
                                       SVal Base) {
   
   if (Base.isUnknownOrUndef())
@@ -158,9 +153,7 @@ SVal BasicStoreManager::getLValueIvar(const GRState *state, const ObjCIvarDecl*
 
   if (isa<loc::MemRegionVal>(BaseL)) {
     const MemRegion *BaseR = cast<loc::MemRegionVal>(BaseL).getRegion();
-
-    if (BaseR == SelfRegion)
-      return ValMgr.makeLoc(MRMgr.getObjCIvarRegion(D, BaseR));
+    return ValMgr.makeLoc(MRMgr.getObjCIvarRegion(D, BaseR));
   }
   
   return UnknownVal();
@@ -343,12 +336,7 @@ Store BasicStoreManager::BindInternal(Store store, Loc loc, SVal V) {
       
   if (!(isa<VarRegion>(R) || isa<ObjCIvarRegion>(R)))
     return store;
-      
-  // We only track bindings to self.ivar.
-  if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R))
-    if (IVR->getSuperRegion() != SelfRegion)
-      return store;
-      
+
   if (nonloc::LocAsInteger *X = dyn_cast<nonloc::LocAsInteger>(&V)) {
     // Only convert 'V' to a location iff the underlying region type
     // is a location as well.
@@ -468,7 +456,8 @@ BasicStoreManager::RemoveDeadBindings(GRState &state, Stmt* Loc,
   state.setStore(store);
 }
 
-Store BasicStoreManager::scanForIvars(Stmt *B, const Decl* SelfDecl, Store St) {
+Store BasicStoreManager::scanForIvars(Stmt *B, const Decl* SelfDecl,
+                                      const MemRegion *SelfRegion, Store St) {
   for (Stmt::child_iterator CI=B->child_begin(), CE=B->child_end();
        CI != CE; ++CI) {
     
@@ -489,7 +478,7 @@ Store BasicStoreManager::scanForIvars(Stmt *B, const Decl* SelfDecl, Store St) {
       }
     }
     else
-      St = scanForIvars(*CI, SelfDecl, St);
+      St = scanForIvars(*CI, SelfDecl, SelfRegion, St);
   }
   
   return St;
@@ -511,17 +500,18 @@ Store BasicStoreManager::getInitialStore(const LocationContext *InitLoc) {
       const Decl& CD = *InitLoc->getDecl();      
       if (const ObjCMethodDecl* MD = dyn_cast<ObjCMethodDecl>(&CD)) {
         if (MD->getSelfDecl() == PD) {
-          // Create a region for "self".
-          assert (SelfRegion == 0);
-          SelfRegion = MRMgr.getObjCObjectRegion(MD->getClassInterface(),
-                                                 MRMgr.getHeapRegion());
+          // FIXME: Just use a symbolic region, and remove ObjCObjectRegion
+          // entirely.
+          const ObjCObjectRegion *SelfRegion =
+            MRMgr.getObjCObjectRegion(MD->getClassInterface(),
+                                      MRMgr.getHeapRegion());
           
           St = BindInternal(St, ValMgr.makeLoc(MRMgr.getVarRegion(PD, InitLoc)),
                             ValMgr.makeLoc(SelfRegion));
           
           // Scan the method for ivar references.  While this requires an
           // entire AST scan, the cost should not be high in practice.
-          St = scanForIvars(MD->getBody(), PD, St);
+          St = scanForIvars(MD->getBody(), PD, SelfRegion, St);
         }
       }
     }
@@ -641,11 +631,6 @@ const GRState *BasicStoreManager::InvalidateRegion(const GRState *state,
   if (!(isa<VarRegion>(R) || isa<ObjCIvarRegion>(R)))
       return state;
       
-  // We only track bindings to self.ivar.
-  if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R))
-    if (IVR->getSuperRegion() != SelfRegion)
-      return state;
-
   QualType T = cast<TypedRegion>(R)->getValueType(R->getContext());
   SVal V = ValMgr.getConjuredSymbolVal(E, T, Count);
   return Bind(state, loc::MemRegionVal(R), V);