diff --git a/src/runtime/runtime-internal.cc b/src/runtime/runtime-internal.cc
new file mode 100644
index 0000000..79dface
--- /dev/null
+++ b/src/runtime/runtime-internal.cc
@@ -0,0 +1,282 @@
+// 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/v8.h"
+
+#include "src/arguments.h"
+#include "src/bootstrapper.h"
+#include "src/debug.h"
+#include "src/runtime/runtime-utils.h"
+
+namespace v8 {
+namespace internal {
+
+RUNTIME_FUNCTION(Runtime_CheckIsBootstrapping) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 0);
+  RUNTIME_ASSERT(isolate->bootstrapper()->IsActive());
+  return isolate->heap()->undefined_value();
+}
+
+
+RUNTIME_FUNCTION(Runtime_Throw) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+
+  return isolate->Throw(args[0]);
+}
+
+
+RUNTIME_FUNCTION(Runtime_ReThrow) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+
+  return isolate->ReThrow(args[0]);
+}
+
+
+RUNTIME_FUNCTION(Runtime_PromoteScheduledException) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 0);
+  return isolate->PromoteScheduledException();
+}
+
+
+RUNTIME_FUNCTION(Runtime_ThrowReferenceError) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(Object, name, 0);
+  THROW_NEW_ERROR_RETURN_FAILURE(
+      isolate, NewReferenceError("not_defined", HandleVector(&name, 1)));
+}
+
+
+RUNTIME_FUNCTION(Runtime_PromiseRejectEvent) {
+  DCHECK(args.length() == 3);
+  HandleScope scope(isolate);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, promise, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, value, 1);
+  CONVERT_BOOLEAN_ARG_CHECKED(debug_event, 2);
+  if (debug_event) isolate->debug()->OnPromiseReject(promise, value);
+  Handle<Symbol> key = isolate->factory()->promise_has_handler_symbol();
+  // Do not report if we actually have a handler.
+  if (JSObject::GetDataProperty(promise, key)->IsUndefined()) {
+    isolate->ReportPromiseReject(promise, value,
+                                 v8::kPromiseRejectWithNoHandler);
+  }
+  return isolate->heap()->undefined_value();
+}
+
+
+RUNTIME_FUNCTION(Runtime_PromiseRevokeReject) {
+  DCHECK(args.length() == 1);
+  HandleScope scope(isolate);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, promise, 0);
+  Handle<Symbol> key = isolate->factory()->promise_has_handler_symbol();
+  // At this point, no revocation has been issued before
+  RUNTIME_ASSERT(JSObject::GetDataProperty(promise, key)->IsUndefined());
+  isolate->ReportPromiseReject(promise, Handle<Object>(),
+                               v8::kPromiseHandlerAddedAfterReject);
+  return isolate->heap()->undefined_value();
+}
+
+
+RUNTIME_FUNCTION(Runtime_PromiseHasHandlerSymbol) {
+  DCHECK(args.length() == 0);
+  return isolate->heap()->promise_has_handler_symbol();
+}
+
+
+RUNTIME_FUNCTION(Runtime_StackGuard) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 0);
+
+  // First check if this is a real stack overflow.
+  StackLimitCheck check(isolate);
+  if (check.JsHasOverflowed()) {
+    return isolate->StackOverflow();
+  }
+
+  return isolate->stack_guard()->HandleInterrupts();
+}
+
+
+RUNTIME_FUNCTION(Runtime_Interrupt) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 0);
+  return isolate->stack_guard()->HandleInterrupts();
+}
+
+
+RUNTIME_FUNCTION(Runtime_AllocateInNewSpace) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_SMI_ARG_CHECKED(size, 0);
+  RUNTIME_ASSERT(IsAligned(size, kPointerSize));
+  RUNTIME_ASSERT(size > 0);
+  RUNTIME_ASSERT(size <= Page::kMaxRegularHeapObjectSize);
+  return *isolate->factory()->NewFillerObject(size, false, NEW_SPACE);
+}
+
+
+RUNTIME_FUNCTION(Runtime_AllocateInTargetSpace) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 2);
+  CONVERT_SMI_ARG_CHECKED(size, 0);
+  CONVERT_SMI_ARG_CHECKED(flags, 1);
+  RUNTIME_ASSERT(IsAligned(size, kPointerSize));
+  RUNTIME_ASSERT(size > 0);
+  RUNTIME_ASSERT(size <= Page::kMaxRegularHeapObjectSize);
+  bool double_align = AllocateDoubleAlignFlag::decode(flags);
+  AllocationSpace space = AllocateTargetSpace::decode(flags);
+  return *isolate->factory()->NewFillerObject(size, double_align, space);
+}
+
+
+// Collect the raw data for a stack trace.  Returns an array of 4
+// element segments each containing a receiver, function, code and
+// native code offset.
+RUNTIME_FUNCTION(Runtime_CollectStackTrace) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, error_object, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, caller, 1);
+
+  if (!isolate->bootstrapper()->IsActive()) {
+    // Optionally capture a more detailed stack trace for the message.
+    isolate->CaptureAndSetDetailedStackTrace(error_object);
+    // Capture a simple stack trace for the stack property.
+    isolate->CaptureAndSetSimpleStackTrace(error_object, caller);
+  }
+  return isolate->heap()->undefined_value();
+}
+
+
+RUNTIME_FUNCTION(Runtime_GetFromCache) {
+  SealHandleScope shs(isolate);
+  // This is only called from codegen, so checks might be more lax.
+  CONVERT_ARG_CHECKED(JSFunctionResultCache, cache, 0);
+  CONVERT_ARG_CHECKED(Object, key, 1);
+
+  {
+    DisallowHeapAllocation no_alloc;
+
+    int finger_index = cache->finger_index();
+    Object* o = cache->get(finger_index);
+    if (o == key) {
+      // The fastest case: hit the same place again.
+      return cache->get(finger_index + 1);
+    }
+
+    for (int i = finger_index - 2; i >= JSFunctionResultCache::kEntriesIndex;
+         i -= 2) {
+      o = cache->get(i);
+      if (o == key) {
+        cache->set_finger_index(i);
+        return cache->get(i + 1);
+      }
+    }
+
+    int size = cache->size();
+    DCHECK(size <= cache->length());
+
+    for (int i = size - 2; i > finger_index; i -= 2) {
+      o = cache->get(i);
+      if (o == key) {
+        cache->set_finger_index(i);
+        return cache->get(i + 1);
+      }
+    }
+  }
+
+  // There is no value in the cache.  Invoke the function and cache result.
+  HandleScope scope(isolate);
+
+  Handle<JSFunctionResultCache> cache_handle(cache);
+  Handle<Object> key_handle(key, isolate);
+  Handle<Object> value;
+  {
+    Handle<JSFunction> factory(JSFunction::cast(
+        cache_handle->get(JSFunctionResultCache::kFactoryIndex)));
+    // TODO(antonm): consider passing a receiver when constructing a cache.
+    Handle<JSObject> receiver(isolate->global_proxy());
+    // This handle is nor shared, nor used later, so it's safe.
+    Handle<Object> argv[] = {key_handle};
+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+        isolate, value,
+        Execution::Call(isolate, factory, receiver, arraysize(argv), argv));
+  }
+
+#ifdef VERIFY_HEAP
+  if (FLAG_verify_heap) {
+    cache_handle->JSFunctionResultCacheVerify();
+  }
+#endif
+
+  // Function invocation may have cleared the cache.  Reread all the data.
+  int finger_index = cache_handle->finger_index();
+  int size = cache_handle->size();
+
+  // If we have spare room, put new data into it, otherwise evict post finger
+  // entry which is likely to be the least recently used.
+  int index = -1;
+  if (size < cache_handle->length()) {
+    cache_handle->set_size(size + JSFunctionResultCache::kEntrySize);
+    index = size;
+  } else {
+    index = finger_index + JSFunctionResultCache::kEntrySize;
+    if (index == cache_handle->length()) {
+      index = JSFunctionResultCache::kEntriesIndex;
+    }
+  }
+
+  DCHECK(index % 2 == 0);
+  DCHECK(index >= JSFunctionResultCache::kEntriesIndex);
+  DCHECK(index < cache_handle->length());
+
+  cache_handle->set(index, *key_handle);
+  cache_handle->set(index + 1, *value);
+  cache_handle->set_finger_index(index);
+
+#ifdef VERIFY_HEAP
+  if (FLAG_verify_heap) {
+    cache_handle->JSFunctionResultCacheVerify();
+  }
+#endif
+
+  return *value;
+}
+
+
+RUNTIME_FUNCTION(Runtime_MessageGetStartPosition) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_CHECKED(JSMessageObject, message, 0);
+  return Smi::FromInt(message->start_position());
+}
+
+
+RUNTIME_FUNCTION(Runtime_MessageGetScript) {
+  SealHandleScope shs(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_CHECKED(JSMessageObject, message, 0);
+  return message->script();
+}
+
+
+RUNTIME_FUNCTION(Runtime_IS_VAR) {
+  UNREACHABLE();  // implemented as macro in the parser
+  return NULL;
+}
+
+
+RUNTIME_FUNCTION(RuntimeReference_GetFromCache) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 2);
+  CONVERT_SMI_ARG_CHECKED(id, 0);
+  args[0] = isolate->native_context()->jsfunction_result_caches()->get(id);
+  return __RT_impl_Runtime_GetFromCache(args, isolate);
+}
+}
+}  // namespace v8::internal