Ensure environment does not contain nil values.

src/compiler/ast-graph-builder.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/ast-graph-builder.h"
 
 #include "src/compiler.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/node-properties.h"
 #include "src/compiler/node-properties-inl.h"
@@ skipping 159 matching lines @@
       locals_count_(scope->num_stack_slots()),
       parameters_node_(NULL),
       locals_node_(NULL),
       stack_node_(NULL),
       parameters_dirty_(false),
       locals_dirty_(false),
       stack_dirty_(false) {
   ASSERT_EQ(scope->num_parameters() + 1, parameters_count());
 
   // Bind the receiver variable.
-  values()->insert(values()->end(), parameters_count(),
-                   static_cast<Node*>(NULL));
   Node* receiver = builder->graph()->NewNode(common()->Parameter(0));
-  Bind(scope->receiver(), receiver);
+  values()->push_back(receiver);
 
   // Bind all parameter variables. The parameter indices are shifted by 1
   // (receiver is parameter index -1 but environment index 0).
   for (int i = 0; i < scope->num_parameters(); ++i) {
-    // Unused parameters are allocated to Variable::UNALLOCATED.
-    if (!scope->parameter(i)->IsParameter()) continue;
     Node* parameter = builder->graph()->NewNode(common()->Parameter(i + 1));
-    Bind(scope->parameter(i), parameter);
+    values()->push_back(parameter);
   }
 
   // Bind all local variables to undefined.
   Node* undefined_constant = builder->jsgraph()->UndefinedConstant();
   values()->insert(values()->end(), locals_count(), undefined_constant);
 }
 
 
 AstGraphBuilder::Environment::Environment(const Environment& copy)
     : StructuredGraphBuilder::Environment(
@@ skipping 1779 matching lines @@
 
     // Continue with the original environment.
     set_environment(continuation_env);
 
     NewNode(common()->Continuation());
   }
 }
 }
 }
 }  // namespace v8::internal::compiler