[interpreter] Add CreateFunctionContext bytecode

src/interpreter/bytecode-generator.cc

 // Copyright 2015 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/interpreter/bytecode-generator.h"
 
 #include "src/ast/scopes.h"
 #include "src/code-stubs.h"
 #include "src/compiler.h"
 #include "src/interpreter/bytecode-flags.h"
@@ skipping 2992 matching lines @@
     Register closure = register_allocator()->NewRegister();
     Register scope_info = register_allocator()->NewRegister();
     DCHECK(Register::AreContiguous(closure, scope_info));
     builder()
         ->LoadAccumulatorWithRegister(Register::function_closure())
         .StoreAccumulatorInRegister(closure)
         .LoadLiteral(scope->GetScopeInfo(isolate()))
         .StoreAccumulatorInRegister(scope_info)
         .CallRuntime(Runtime::kNewScriptContext, closure, 2);
   } else {
-    builder()->CallRuntime(Runtime::kNewFunctionContext,
-                           Register::function_closure(), 1);
+    builder()->CreateFunctionContext(
+        scope->GetScopeInfo(isolate())->ContextLength());

[Michael Starzinger, 2016/08/02 11:58:41]

Using the {ScopeInfo} here looks dangerous. The slot count should be ...

int slot_count = scope->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;

[klaasb, 2016/08/02 13:02:25]

Fixed.

   }
   execution_result()->SetResultInAccumulator();
 }
 
 void BytecodeGenerator::VisitBuildLocalActivationContext() {
   Scope* scope = this->scope();
 
   if (scope->has_this_declaration() && scope->receiver()->IsContextSlot()) {
     Variable* variable = scope->receiver();
     Register receiver(builder()->Parameter(0));
@@ skipping 212 matching lines @@
   return execution_context()->scope()->language_mode();
 }
 
 int BytecodeGenerator::feedback_index(FeedbackVectorSlot slot) const {
   return TypeFeedbackVector::GetIndex(slot);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8