Skip back edge creation for "do ... while(false)" loops

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 3c4ff159eb22b9b92595a5843f83c492c6c2d589..db5befd3cde1a8a857ef1b5aca4566fe6e045125 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -4319,12 +4319,17 @@ void HOptimizedGraphBuilder::VisitDoWhileStatement(DoWhileStatement* stmt) {
   HBasicBlock* loop_successor = NULL;
   if (body_exit != NULL && !stmt->cond()->ToBooleanIsTrue()) {
     set_current_block(body_exit);
-    // The block for a true condition, the actual predecessor block of the
-    // back edge.
-    body_exit = graph()->CreateBasicBlock();
     loop_successor = graph()->CreateBasicBlock();
-    CHECK_BAILOUT(VisitForControl(stmt->cond(), body_exit, loop_successor));
-    if (body_exit->HasPredecessor()) {
+    if (stmt->cond()->ToBooleanIsFalse()) {
+      Goto(loop_successor);
+      body_exit = NULL;
+    } else {
+      // The block for a true condition, the actual predecessor block of the
+      // back edge.
+      body_exit = graph()->CreateBasicBlock();
+      CHECK_BAILOUT(VisitForControl(stmt->cond(), body_exit, loop_successor));
+    }
+    if (body_exit != NULL && body_exit->HasPredecessor()) {
       body_exit->SetJoinId(stmt->BackEdgeId());
     } else {
       body_exit = NULL;