Remove the CFGElement "Invalid" state.

Use Optional<CFG*> where invalid states were needed previously. In the one case
where that's not possible (beginAutomaticObjDtorsInsert) just use a dummy
CFGAutomaticObjDtor.

Thanks for the help from Jordan Rose & discussion/feedback from Ted Kremenek
and Doug Gregor.

Post commit code review feedback on r175796 by Ted Kremenek.

llvm-svn: 175938

1 files changed, 19 insertions, 19 deletions

diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp
index 8754fe86a86..4d20467a79d 100644
--- a/clang/lib/Analysis/CFG.cpp
+++ b/clang/lib/Analysis/CFG.cpp
@@ -3332,7 +3332,6 @@ CFG* CFG::buildCFG(const Decl *D, Stmt *Statement, ASTContext *C,
 const CXXDestructorDecl *
 CFGImplicitDtor::getDestructorDecl(ASTContext &astContext) const {
   switch (getKind()) {
-    case CFGElement::Invalid:
     case CFGElement::Statement:
     case CFGElement::Initializer:
       llvm_unreachable("getDestructorDecl should only be used with "
@@ -3406,8 +3405,8 @@ static BlkExprMapTy* PopulateBlkExprMap(CFG& cfg) {
 
   for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I)
     for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI)
-      if (CFGStmt S = BI->getAs<CFGStmt>())
-        FindSubExprAssignments(S.getStmt(), SubExprAssignments);
+      if (Optional<CFGStmt> S = BI->getAs<CFGStmt>())
+        FindSubExprAssignments(S->getStmt(), SubExprAssignments);
 
   for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I) {
 
@@ -3415,10 +3414,10 @@ static BlkExprMapTy* PopulateBlkExprMap(CFG& cfg) {
     // block-level that are block-level expressions.
 
     for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI) {
-      CFGStmt CS = BI->getAs<CFGStmt>();
+      Optional<CFGStmt> CS = BI->getAs<CFGStmt>();
       if (!CS)
         continue;
-      if (const Expr *Exp = dyn_cast<Expr>(CS.getStmt())) {
+      if (const Expr *Exp = dyn_cast<Expr>(CS->getStmt())) {
         assert((Exp->IgnoreParens() == Exp) && "No parens on block-level exps");
 
         if (const BinaryOperator* B = dyn_cast<BinaryOperator>(Exp)) {
@@ -3531,8 +3530,8 @@ public:
       unsigned j = 1;
       for (CFGBlock::const_iterator BI = (*I)->begin(), BEnd = (*I)->end() ;
            BI != BEnd; ++BI, ++j ) {        
-        if (CFGStmt SE = BI->getAs<CFGStmt>()) {
-          const Stmt *stmt= SE.getStmt();
+        if (Optional<CFGStmt> SE = BI->getAs<CFGStmt>()) {
+          const Stmt *stmt= SE->getStmt();
           std::pair<unsigned, unsigned> P((*I)->getBlockID(), j);
           StmtMap[stmt] = P;
 
@@ -3721,8 +3720,8 @@ public:
 
 static void print_elem(raw_ostream &OS, StmtPrinterHelper* Helper,
                        const CFGElement &E) {
-  if (CFGStmt CS = E.getAs<CFGStmt>()) {
-    const Stmt *S = CS.getStmt();
+  if (Optional<CFGStmt> CS = E.getAs<CFGStmt>()) {
+    const Stmt *S = CS->getStmt();
     
     if (Helper) {
 
@@ -3769,8 +3768,8 @@ static void print_elem(raw_ostream &OS, StmtPrinterHelper* Helper,
     if (isa<Expr>(S))
       OS << '\n';
 
-  } else if (CFGInitializer IE = E.getAs<CFGInitializer>()) {
-    const CXXCtorInitializer *I = IE.getInitializer();
+  } else if (Optional<CFGInitializer> IE = E.getAs<CFGInitializer>()) {
+    const CXXCtorInitializer *I = IE->getInitializer();
     if (I->isBaseInitializer())
       OS << I->getBaseClass()->getAsCXXRecordDecl()->getName();
     else OS << I->getAnyMember()->getName();
@@ -3784,8 +3783,9 @@ static void print_elem(raw_ostream &OS, StmtPrinterHelper* Helper,
       OS << " (Base initializer)\n";
     else OS << " (Member initializer)\n";
 
-  } else if (CFGAutomaticObjDtor DE = E.getAs<CFGAutomaticObjDtor>()){
-    const VarDecl *VD = DE.getVarDecl();
+  } else if (Optional<CFGAutomaticObjDtor> DE =
+                 E.getAs<CFGAutomaticObjDtor>()) {
+    const VarDecl *VD = DE->getVarDecl();
     Helper->handleDecl(VD, OS);
 
     const Type* T = VD->getType().getTypePtr();
@@ -3796,20 +3796,20 @@ static void print_elem(raw_ostream &OS, StmtPrinterHelper* Helper,
     OS << ".~" << T->getAsCXXRecordDecl()->getName().str() << "()";
     OS << " (Implicit destructor)\n";
 
-  } else if (CFGBaseDtor BE = E.getAs<CFGBaseDtor>()) {
-    const CXXBaseSpecifier *BS = BE.getBaseSpecifier();
+  } else if (Optional<CFGBaseDtor> BE = E.getAs<CFGBaseDtor>()) {
+    const CXXBaseSpecifier *BS = BE->getBaseSpecifier();
     OS << "~" << BS->getType()->getAsCXXRecordDecl()->getName() << "()";
     OS << " (Base object destructor)\n";
 
-  } else if (CFGMemberDtor ME = E.getAs<CFGMemberDtor>()) {
-    const FieldDecl *FD = ME.getFieldDecl();
+  } else if (Optional<CFGMemberDtor> ME = E.getAs<CFGMemberDtor>()) {
+    const FieldDecl *FD = ME->getFieldDecl();
     const Type *T = FD->getType()->getBaseElementTypeUnsafe();
     OS << "this->" << FD->getName();
     OS << ".~" << T->getAsCXXRecordDecl()->getName() << "()";
     OS << " (Member object destructor)\n";
 
-  } else if (CFGTemporaryDtor TE = E.getAs<CFGTemporaryDtor>()) {
-    const CXXBindTemporaryExpr *BT = TE.getBindTemporaryExpr();
+  } else if (Optional<CFGTemporaryDtor> TE = E.getAs<CFGTemporaryDtor>()) {
+    const CXXBindTemporaryExpr *BT = TE->getBindTemporaryExpr();
     OS << "~" << BT->getType()->getAsCXXRecordDecl()->getName() << "()";
     OS << " (Temporary object destructor)\n";
   }