Fix a couple bugs:
- NonLoc::MakeVal() would use sizeof(unsigned) (literally) instead of consulting
  ASTContext for the size (in bits) of 'int'. While it worked, it was a
  conflation of concepts and using ASTContext.IntTy is 100% correct.
- RegionStore::getSizeInElements() no longer assumes that a VarRegion has the
  type "ConstantArray", and handles the case when uses use ordinary variables
  as if they were arrays.
- Fixed ElementRegion::getRValueType() to just return the rvalue type of its
  "array region" in the case the array didn't have ArrayType.
- All of this fixes <rdar://problem/6541136>


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@63347 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/MemRegion.cpp b/lib/Analysis/MemRegion.cpp
index 55c6935..82f4423 100644
--- a/lib/Analysis/MemRegion.cpp
+++ b/lib/Analysis/MemRegion.cpp
@@ -114,8 +114,9 @@
   if (ArrayType* AT = dyn_cast<ArrayType>(T.getTypePtr()))
     return AT->getElementType();
 
-  PointerType* PtrT = cast<PointerType>(T.getTypePtr());
-  return C.getCanonicalType(PtrT->getPointeeType());
+  // If the RValueType of the array region isn't an ArrayType, then essentially
+  // the element's  
+  return T;
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/lib/Analysis/RegionStore.cpp b/lib/Analysis/RegionStore.cpp
index e50b0ab..8d36d10 100644
--- a/lib/Analysis/RegionStore.cpp
+++ b/lib/Analysis/RegionStore.cpp
@@ -403,20 +403,27 @@
                                            const MemRegion* R) {
   if (const VarRegion* VR = dyn_cast<VarRegion>(R)) {
     // Get the type of the variable.
-    QualType T = VR->getRValueType(getContext());
+    QualType T = VR->getDesugaredRValueType(getContext());
 
-    // It must be of array type. 
-    const ConstantArrayType* CAT = cast<ConstantArrayType>(T.getTypePtr());
-
-    // return the size as signed integer.
-    return NonLoc::MakeVal(getBasicVals(), CAT->getSize(), false);
+    // FIXME: Handle variable-length arrays.
+    if (isa<VariableArrayType>(T))
+      return UnknownVal();
+    
+    if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(T)) {
+      // return the size as signed integer.
+      return NonLoc::MakeVal(getBasicVals(), CAT->getSize(), false);
+    }
+    
+    // Clients can use ordinary variables as if they were arrays.  These
+    // essentially are arrays of size 1.
+    return NonLoc::MakeIntVal(getBasicVals(), 1, false);
   }
 
   if (const StringRegion* SR = dyn_cast<StringRegion>(R)) {
     const StringLiteral* Str = SR->getStringLiteral();
     // We intentionally made the size value signed because it participates in 
     // operations with signed indices.
-    return NonLoc::MakeVal(getBasicVals(), Str->getByteLength() + 1, false);
+    return NonLoc::MakeIntVal(getBasicVals(), Str->getByteLength()+1, false);
   }
 
   if (const AnonTypedRegion* ATR = dyn_cast<AnonTypedRegion>(R)) {
@@ -880,8 +887,8 @@
 
   // When we are binding the whole array, it always has default value 0.
   GRStateRef state(St, StateMgr);
-  St = state.set<RegionDefaultValue>(R, NonLoc::MakeVal(getBasicVals(), 0, 
-                                                        false));
+  St = state.set<RegionDefaultValue>(R, NonLoc::MakeIntVal(getBasicVals(), 0, 
+                                                           false));
 
   Store store = St->getStore();
 
@@ -961,8 +968,8 @@
     // struct decl. In this case, mark the region as having default value.
     if (VI == VE) {
       GRStateRef state(St, StateMgr);
-      St = state.set<RegionDefaultValue>(R, NonLoc::MakeVal(getBasicVals(), 0, 
-                                                            false));
+      const NonLoc& Idx = NonLoc::MakeIntVal(getBasicVals(), 0, false);
+      St = state.set<RegionDefaultValue>(R, Idx);
       break;
     }
 
diff --git a/lib/Analysis/SVals.cpp b/lib/Analysis/SVals.cpp
index 6847764..824d722 100644
--- a/lib/Analysis/SVals.cpp
+++ b/lib/Analysis/SVals.cpp
@@ -247,10 +247,9 @@
   return nonloc::SymbolVal(sym);
 }
 
-NonLoc NonLoc::MakeVal(BasicValueFactory& BasicVals, unsigned X, 
-                       bool isUnsigned) {
-  return nonloc::ConcreteInt(BasicVals.getValue(X, sizeof(unsigned)*8, 
-                                                isUnsigned));
+NonLoc NonLoc::MakeIntVal(BasicValueFactory& BasicVals, uint64_t X, 
+                          bool isUnsigned) {
+  return nonloc::ConcreteInt(BasicVals.getIntValue(X, isUnsigned));
 }
 
 NonLoc NonLoc::MakeVal(BasicValueFactory& BasicVals, uint64_t X,