Refactor 'BasicStoreManager::CastRegion' and 'RegionStoreManager::CastRegion'
into StoreManager::CastRegion. Both methods were practically identical, and this
is core logic that is common to all StoreManagers since it defines the basic
invariants of the abstract memory model.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69730 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/Store.cpp b/lib/Analysis/Store.cpp
new file mode 100644
index 0000000..edd353d
--- /dev/null
+++ b/lib/Analysis/Store.cpp
@@ -0,0 +1,47 @@
+//== Store.cpp - Interface for maps from Locations to Values ----*- C++ -*--==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defined the types Store and StoreManager.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/Store.h"
+#include "clang/Analysis/PathSensitive/GRState.h"
+
+using namespace clang;
+
+StoreManager::StoreManager(GRStateManager &stateMgr)
+  : ValMgr(stateMgr.getValueManager()),
+    StateMgr(stateMgr),
+    MRMgr(ValMgr.getRegionManager()) {}
+
+StoreManager::CastResult
+StoreManager::CastRegion(const GRState* state, const MemRegion* R,
+                               QualType CastToTy) {
+  
+  // Return the same region if the region types are compatible.
+  if (const TypedRegion* TR = dyn_cast<TypedRegion>(R)) {
+    ASTContext& Ctx = StateMgr.getContext();
+    QualType Ta = Ctx.getCanonicalType(TR->getLValueType(Ctx));
+    QualType Tb = Ctx.getCanonicalType(CastToTy);
+    
+    if (Ta == Tb)
+      return CastResult(state, R);
+  }
+  
+  // FIXME: We should handle the case when we are casting *back* to a
+  // previous type. For example:
+  //
+  //      void* x = ...;
+  //      char* y = (char*) x;
+  //      void* z = (void*) y; // <-- we should get the same region that is 
+  //                                  bound to 'x'
+  const MemRegion* ViewR = MRMgr.getTypedViewRegion(CastToTy, R);  
+  return CastResult(AddRegionView(state, ViewR, R), ViewR);
+}