Add parser support for generators.

src/hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3787 matching lines @@
 
 void HOptimizedGraphBuilder::VisitExpressions(
     ZoneList<Expression*>* exprs) {
   for (int i = 0; i < exprs->length(); ++i) {
     CHECK_ALIVE(VisitForValue(exprs->at(i)));
   }
 }
 
 
 bool HOptimizedGraphBuilder::BuildGraph() {
+  if (info()->function()->is_generator()) {
+    Bailout("function is a generator");
+    return false;
+  }
   Scope* scope = info()->scope();
   if (scope->HasIllegalRedeclaration()) {
     Bailout("function with illegal redeclaration");
     return false;
   }
   if (scope->calls_eval()) {
     Bailout("function calls eval");
     return false;
   }
   SetUpScope(scope);
@@ skipping 2840 matching lines @@
 
       case Variable::LOOKUP:
         return Bailout("assignment to LOOKUP variable");
     }
   } else {
     return Bailout("invalid left-hand side in assignment");
   }
 }
 
 
+void HOptimizedGraphBuilder::VisitYield(Yield* expr) {
+  // Generators are not optimized, so we should never get here.
+  UNREACHABLE();
+}
+
+
 void HOptimizedGraphBuilder::VisitThrow(Throw* expr) {
   ASSERT(!HasStackOverflow());
   ASSERT(current_block() != NULL);
   ASSERT(current_block()->HasPredecessor());
   // We don't optimize functions with invalid left-hand sides in
   // assignments, count operations, or for-in.  Consequently throw can
   // currently only occur in an effect context.
   ASSERT(ast_context()->IsEffect());
   CHECK_ALIVE(VisitForValue(expr->exception()));
 
@@ skipping 4198 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal