From 0b1d9b7557437176f9cea1283bfac2510812bece Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Mon, 27 Aug 2007 21:54:41 +0000
Subject: [PATCH] Added support for short-circuit '&&' and '||' operators in
 source-level CFGs.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41520 91177308-0d34-0410-b5e6-96231b3b80d8
---
 AST/CFG.cpp | 41 +++++++++++++++++++++++++++++++++++------
 1 file changed, 35 insertions(+), 6 deletions(-)

diff --git a/AST/CFG.cpp b/AST/CFG.cpp
index 203348f7f3..b79bfe519b 100644
--- a/AST/CFG.cpp
+++ b/AST/CFG.cpp
@@ -210,6 +210,37 @@ CFGBlock* CFGBuilder::WalkAST(Stmt* S, bool AlwaysAddStmt = false) {
       Block->setTerminator(C);
       return addStmt(C->getCond());
     }
+    
+    case Stmt::ParenExprClass:
+      return WalkAST(cast<ParenExpr>(S)->getSubExpr(),AlwaysAddStmt);
+    
+    case Stmt::BinaryOperatorClass: {
+      BinaryOperator* B = cast<BinaryOperator>(S);
+
+      if (B->isLogicalOp()) { // && or ||
+        CFGBlock* ConfluenceBlock = (Block) ? Block : createBlock();  
+        ConfluenceBlock->appendStmt(B);
+        FinishBlock(ConfluenceBlock);
+
+        // create the block evaluating the LHS
+        CFGBlock* LHSBlock = createBlock(false);
+        LHSBlock->addSuccessor(ConfluenceBlock);
+        LHSBlock->setTerminator(B);        
+        
+        // create the block evaluating the RHS
+        Succ = ConfluenceBlock;
+        Block = NULL;
+        CFGBlock* RHSBlock = Visit(B->getRHS());
+        LHSBlock->addSuccessor(RHSBlock);
+        
+        // Generate the blocks for evaluating the LHS.
+        Block = LHSBlock;
+        return addStmt(B->getLHS());                                    
+      }    
+
+      // Fall through to the default case.
+    }
+    
     default:
       if (AlwaysAddStmt) Block->appendStmt(S);
       return WalkAST_VisitChildren(S);
@@ -218,8 +249,7 @@ CFGBlock* CFGBuilder::WalkAST(Stmt* S, bool AlwaysAddStmt = false) {
 
 /// WalkAST_VisitChildren - Utility method to call WalkAST on the
 ///  children of a Stmt.
-CFGBlock* CFGBuilder::WalkAST_VisitChildren(Stmt* S)
-{
+CFGBlock* CFGBuilder::WalkAST_VisitChildren(Stmt* S) {
   CFGBlock* B = Block;
   for (Stmt::child_iterator I = S->child_begin(), E = S->child_end() ;
        I != E; ++I)
@@ -833,11 +863,10 @@ public:
     OS << '\n';
   }
   
-  void VisitConditionalOperator(ConditionalOperator* C) {
-    C->printPretty(OS);
+  void VisitExpr(Expr* E) {
+    E->printPretty(OS);
     OS << '\n';
-  }
-                                                     
+  }                                                       
 };
 } // end anonymous namespace
 
-- 
2.40.0