This is the first step to implement a field-sensitive store model. Other things are simplified: no heap shape assumption, no parameter alias assumption, etc.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@57285 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 96 insertions, 0 deletions

diff --git a/lib/Analysis/RegionStore.cpp b/lib/Analysis/RegionStore.cpp
new file mode 100644
index 0000000000..7004c5558e
--- /dev/null
+++ b/lib/Analysis/RegionStore.cpp
@@ -0,0 +1,96 @@
+//== RegionStore.cpp - Field-sensitive store model --------------*- C++ -*--==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a basic region store model. In this model, we do have field
+// sensitivity. But we assume nothing about the heap shape. So recursive data
+// structures are largely ignored. Basically we do 1-limiting analysis.
+// Parameter pointers are assumed with no aliasing. Pointee objects of
+// parameters are created lazily.
+//
+//===----------------------------------------------------------------------===//
+#include "clang/Analysis/PathSensitive/MemRegion.h"
+#include "clang/Analysis/PathSensitive/GRState.h"
+#include "clang/Analysis/Analyses/LiveVariables.h"
+
+#include "llvm/ADT/ImmutableMap.h"
+#include "llvm/Support/Compiler.h"
+
+using namespace clang;
+
+typedef llvm::ImmutableMap<const MemRegion*, RVal> RegionBindingsTy;
+
+namespace {
+
+class VISIBILITY_HIDDEN RegionStoreManager : public StoreManager {
+  RegionBindingsTy::Factory RBFactory;
+  GRStateManager& StateMgr;
+  MemRegionManager MRMgr;
+
+public:
+  RegionStoreManager(GRStateManager& mgr) 
+    : StateMgr(mgr), MRMgr(StateMgr.getAllocator()) {}
+
+  virtual ~RegionStoreManager() {}
+
+  Store SetRVal(Store St, LVal LV, RVal V);
+
+  Store getInitialStore();
+
+  static inline RegionBindingsTy GetRegionBindings(Store store) {
+   return RegionBindingsTy(static_cast<const RegionBindingsTy::TreeTy*>(store));
+  }
+};
+
+} // end anonymous namespace
+
+Store RegionStoreManager::SetRVal(Store store, LVal LV, RVal V) {
+  assert(LV.getSubKind() == lval::MemRegionKind);
+
+  MemRegion* R = cast<lval::MemRegionVal>(LV).getRegion();
+  
+  if (!R)
+    return store;
+
+  RegionBindingsTy B = GetRegionBindings(store);
+  return V.isUnknown()
+         ? RBFactory.Remove(B, R).getRoot()
+         : RBFactory.Add(B, R, V).getRoot();
+}
+
+Store RegionStoreManager::getInitialStore() {
+  typedef LiveVariables::AnalysisDataTy LVDataTy;
+  LVDataTy& D = StateMgr.getLiveVariables().getAnalysisData();
+
+  Store St = RBFactory.GetEmptyMap().getRoot();
+
+  for (LVDataTy::decl_iterator I=D.begin_decl(), E=D.end_decl(); I != E; ++I) {
+    ScopedDecl* SD = const_cast<ScopedDecl*>(I->first);
+
+    if (VarDecl* VD = dyn_cast<VarDecl>(SD)) {
+      // Punt on static variables for now.
+      if (VD->getStorageClass() == VarDecl::Static)
+        continue;
+
+      QualType T = VD->getType();
+      // Only handle pointers and integers for now.
+      if (LVal::IsLValType(T) || T->isIntegerType()) {
+        MemRegion* R = MRMgr.getVarRegion(VD);
+        // Initialize globals and parameters to symbolic values.
+        // Initialize local variables to undefined.
+        RVal X = (VD->hasGlobalStorage() || isa<ParmVarDecl>(VD) ||
+                  isa<ImplicitParamDecl>(VD))
+                 ? RVal::GetSymbolValue(StateMgr.getSymbolManager(), VD)
+                 : UndefinedVal();
+
+        St = SetRVal(St, lval::MemRegionVal(R), X);
+      }
+    }
+  }
+  return St;
+}