Major rewrite/refactoring of static analysis engine. We now use
EvalStore/EvalLoad to handle all loads/stores from symbolic memory, allowing us
to do checks for null dereferences, etc., at any arbitrary load/store (these
were missed checks before). This also resulted in some major cleanups, some
conceptual, and others just in the structure of the code.

This temporarily introduces a regression in the test suite (null-deref-ps.c)
before I add a new LVal type for structure fields.

llvm-svn: 50443
diff --git a/clang/lib/Analysis/GRCoreEngine.cpp b/clang/lib/Analysis/GRCoreEngine.cpp
index c2b8c11..05f9303 100644
--- a/clang/lib/Analysis/GRCoreEngine.cpp
+++ b/clang/lib/Analysis/GRCoreEngine.cpp
@@ -102,7 +102,8 @@
       case ProgramPoint::BlockExitKind:
         assert (false && "BlockExit location never occur in forward analysis.");
         break;
-        
+      
+      case ProgramPoint::PostLoadKind:
       case ProgramPoint::PostStmtKind:
         HandlePostStmt(cast<PostStmt>(Node->getLocation()), WU.getBlock(),
                        WU.getIndex(), Node);
@@ -316,11 +317,13 @@
     Eng.WList->Enqueue(Succ, B, Idx+1);
 }
 
-ExplodedNodeImpl* GRStmtNodeBuilderImpl::generateNodeImpl(Stmt* S, void* State,
-                                                      ExplodedNodeImpl* Pred) {
+ExplodedNodeImpl*
+GRStmtNodeBuilderImpl::generateNodeImpl(Stmt* S, void* State,
+                                        ExplodedNodeImpl* Pred, bool isLoad) {
   
   bool IsNew;
-  ExplodedNodeImpl* N = Eng.G->getNodeImpl(PostStmt(S), State, &IsNew);
+  ProgramPoint Loc = isLoad ? PostLoad(S) : PostStmt(S);
+  ExplodedNodeImpl* N = Eng.G->getNodeImpl(Loc, State, &IsNew);
   N->addPredecessor(Pred);
   Deferred.erase(Pred);