Introduce new CFGElement hierarchy to support C++ CFG, based on Marcin's patch
and discussions with Ted and Jordy.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@114056 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp
index cc3a388..963d45d 100644
--- a/lib/Analysis/CFG.cpp
+++ b/lib/Analysis/CFG.cpp
@@ -1846,15 +1846,19 @@
 
   for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I)
     for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI)
-      FindSubExprAssignments(*BI, SubExprAssignments);
+      if (CFGStmt S = BI->getAs<CFGStmt>())
+        FindSubExprAssignments(S, SubExprAssignments);
 
   for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I) {
 
     // Iterate over the statements again on identify the Expr* and Stmt* at the
     // block-level that are block-level expressions.
 
-    for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI)
-      if (Expr* Exp = dyn_cast<Expr>(*BI)) {
+    for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI) {
+      CFGStmt CS = BI->getAs<CFGStmt>();
+      if (!CS.isValid())
+        continue;
+      if (Expr* Exp = dyn_cast<Expr>(CS.getStmt())) {
 
         if (BinaryOperator* B = dyn_cast<BinaryOperator>(Exp)) {
           // Assignment expressions that are not nested within another
@@ -1875,6 +1879,7 @@
         unsigned x = M->size();
         (*M)[Exp] = x;
       }
+    }
 
     // Look at terminators.  The condition is a block-level expression.
 
@@ -1959,9 +1964,13 @@
     for (CFG::const_iterator I = cfg->begin(), E = cfg->end(); I != E; ++I ) {
       unsigned j = 1;
       for (CFGBlock::const_iterator BI = (*I)->begin(), BEnd = (*I)->end() ;
-           BI != BEnd; ++BI, ++j )
-        StmtMap[*BI] = std::make_pair((*I)->getBlockID(),j);
+           BI != BEnd; ++BI, ++j ) {
+        CFGStmt CS = BI->getAs<CFGStmt>();
+        if (!CS.isValid())
+          continue;
+        StmtMap[CS] = std::make_pair((*I)->getBlockID(),j);
       }
+    }
   }
 
   virtual ~StmtPrinterHelper() {}
@@ -2090,7 +2099,10 @@
 
 static void print_stmt(llvm::raw_ostream &OS, StmtPrinterHelper* Helper,
                        const CFGElement &E) {
-  Stmt *S = E;
+  CFGStmt CS = E.getAs<CFGStmt>();
+  if (!CS)
+    return;
+  Stmt *S = CS.getStmt();
   
   if (Helper) {
     // special printing for statement-expressions.
diff --git a/lib/Analysis/CFGStmtMap.cpp b/lib/Analysis/CFGStmtMap.cpp
index 965eca1..3a030f9 100644
--- a/lib/Analysis/CFGStmtMap.cpp
+++ b/lib/Analysis/CFGStmtMap.cpp
@@ -50,15 +50,18 @@
   // First walk the block-level expressions.
   for (CFGBlock::iterator I = B->begin(), E = B->end(); I != E; ++I) {
     const CFGElement &CE = *I;
-    if (Stmt *S = CE.getStmt()) {
-      CFGBlock *&Entry = SM[S];
-      // If 'Entry' is already initialized (e.g., a terminator was already),
-      // skip.
-      if (Entry)
-        continue;
+    CFGStmt CS = CE.getAs<CFGStmt>();
+    if (!CS.isValid())
+      continue;
+    
+    CFGBlock *&Entry = SM[CS];
+    // If 'Entry' is already initialized (e.g., a terminator was already),
+    // skip.
+    if (Entry)
+      continue;
       
-      Entry = B;
-    }
+    Entry = B;
+    
   }
   
   // Look at the label of the block.
diff --git a/lib/Analysis/ReachableCode.cpp b/lib/Analysis/ReachableCode.cpp
index eb3f7d4..0088264 100644
--- a/lib/Analysis/ReachableCode.cpp
+++ b/lib/Analysis/ReachableCode.cpp
@@ -31,9 +31,13 @@
   R1 = R2 = SourceRange();
 
 top:
-  if (sn < b.size())
-    S = b[sn].getStmt();
-  else if (b.getTerminator())
+  if (sn < b.size()) {
+    CFGStmt CS = b[sn].getAs<CFGStmt>();
+    if (!CS)
+      goto top;
+    
+    S = CS.getStmt(); 
+  } else if (b.getTerminator())
     S = b.getTerminator();
   else
     return SourceLocation();
@@ -43,7 +47,7 @@
       const BinaryOperator *BO = cast<BinaryOperator>(S);
       if (BO->getOpcode() == BO_Comma) {
         if (sn+1 < b.size())
-          return b[sn+1].getStmt()->getLocStart();
+          return b[sn+1].getAs<CFGStmt>().getStmt()->getLocStart();
         const CFGBlock *n = &b;
         while (1) {
           if (n->getTerminator())
@@ -54,7 +58,7 @@
           if (n->pred_size() != 1)
             return SourceLocation();
           if (!n->empty())
-            return n[0][0].getStmt()->getLocStart();
+            return n[0][0].getAs<CFGStmt>().getStmt()->getLocStart();
         }
       }
       R1 = BO->getLHS()->getSourceRange();