Major refactoring/cleanup of GRExprEngine, ExplodedGraph, and BugReporter.

Bugs are now reported using a combination of "BugType" (previously
BugDescription) and Bug "BugReport" objects, which are fed to BugReporter (which
generates PathDiagnostics). This provides a far more modular way of registering
bug types and plugging in diagnostics.

GRExprEngine now owns its copy of GRCoreEngine, and is not owned by the
ExplodedGraph.

ExplodedGraph is no longer templated on the "checker", but instead on the state
contained in the nodes.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@49453 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/BasicObjCFoundationChecks.cpp b/lib/Analysis/BasicObjCFoundationChecks.cpp
index 6149abe..154adca 100644
--- a/lib/Analysis/BasicObjCFoundationChecks.cpp
+++ b/lib/Analysis/BasicObjCFoundationChecks.cpp
@@ -54,51 +54,61 @@
 
 namespace {
   
-class VISIBILITY_HIDDEN NilArg : public BugDescription {
-  std::string Msg;
-  const char* s;
-  SourceRange R;
+class VISIBILITY_HIDDEN NilArg : public BugType {
 public:
-  NilArg(ObjCMessageExpr* ME, unsigned Arg);
   virtual ~NilArg() {}
   
   virtual const char* getName() const {
     return "nil argument";
   }
   
-  virtual const char* getDescription() const {
-    return s;
-  }
-  
-  virtual void getRanges(const SourceRange*& beg,
-                         const SourceRange*& end) const {
-    beg = &R;
-    end = beg+1;
-  }
+  class Report : public BugReport {
+    std::string Msg;
+    const char* s;
+    SourceRange R;
+  public:
     
+    Report(NilArg& Desc, ObjCMessageExpr* ME, unsigned Arg) : BugReport(Desc) {
+      
+      Expr* E = ME->getArg(Arg);
+      R = E->getSourceRange();
+      
+      std::ostringstream os;
+      
+      os << "Argument to '" << GetReceiverNameType(ME) << "' method '"
+      << ME->getSelector().getName() << "' cannot be nil.";
+      
+      Msg = os.str();
+      s = Msg.c_str();      
+    }
+    
+    virtual ~Report() {}
+    
+    virtual PathDiagnosticPiece* getEndPath(ASTContext& Ctx,
+                                            ExplodedNode<ValueState> *N) const {
+      
+      Stmt* S = cast<PostStmt>(N->getLocation()).getStmt();
+      
+      if (!S)
+        return NULL;
+      
+      FullSourceLoc L(S->getLocStart(), Ctx.getSourceManager());
+      PathDiagnosticPiece* P = new PathDiagnosticPiece(L, s);
+      
+      P->addRange(R);
+      
+      return P;
+    }
+  };  
 };
-  
-NilArg::NilArg(ObjCMessageExpr* ME, unsigned Arg) : s(NULL) {
-  
-  Expr* E = ME->getArg(Arg);
-  R = E->getSourceRange();
-  
-  std::ostringstream os;
-  
-  os << "Argument to '" << GetReceiverNameType(ME) << "' method '"
-     << ME->getSelector().getName() << "' cannot be nil.";
-  
-  Msg = os.str();
-  s = Msg.c_str();
-}
-  
+
   
 class VISIBILITY_HIDDEN BasicObjCFoundationChecks : public GRSimpleAPICheck {
-
+  NilArg Desc;
   ASTContext &Ctx;
   ValueStateManager* VMgr;
   
-  typedef std::vector<std::pair<NodeTy*,BugDescription*> > ErrorsTy;
+  typedef std::vector<std::pair<NodeTy*,BugReport*> > ErrorsTy;
   ErrorsTy Errors;
       
   RVal GetRVal(ValueState* St, Expr* E) { return VMgr->GetRVal(St, E); }
@@ -122,18 +132,16 @@
   
   virtual bool Audit(ExplodedNode<ValueState>* N);
   
-  virtual void ReportResults(Diagnostic& Diag, PathDiagnosticClient* PD,
-                             ASTContext& Ctx, BugReporter& BR,
-                             ExplodedGraph<GRExprEngine>& G);
+  virtual void EmitWarnings(BugReporter& BR);
   
 private:
   
-  void AddError(NodeTy* N, BugDescription* D) {
-    Errors.push_back(std::make_pair(N, D));
+  void AddError(NodeTy* N, BugReport* R) {
+    Errors.push_back(std::make_pair(N, R));
   }
   
   void WarnNilArg(NodeTy* N, ObjCMessageExpr* ME, unsigned Arg) {
-    AddError(N, new NilArg(ME, Arg));
+    AddError(N, new NilArg::Report(Desc, ME, Arg));
   }
 };
   
@@ -186,13 +194,11 @@
 //===----------------------------------------------------------------------===//
 
 
-void BasicObjCFoundationChecks::ReportResults(Diagnostic& Diag,
-                                              PathDiagnosticClient* PD,
-                                              ASTContext& Ctx, BugReporter& BR,
-                                              ExplodedGraph<GRExprEngine>& G) {
-    
+void BasicObjCFoundationChecks::EmitWarnings(BugReporter& BR) {    
+                 
   for (ErrorsTy::iterator I=Errors.begin(), E=Errors.end(); I!=E; ++I)
-    BR.EmitPathWarning(Diag, PD, Ctx, *I->second, G, I->first);
+    
+    BR.EmitPathWarning(*I->second, I->first);
 }
 
 bool BasicObjCFoundationChecks::CheckNilArg(NodeTy* N, unsigned Arg) {