Trace signature types in the tree shaker.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/become.h"
@@ skipping 5635 matching lines @@
     ASSERT(obj.IsArray());
     ASSERT((Array::Cast(obj).At(1) == Object::null()) || value.IsNull());
     Array::Cast(obj).SetAt(1, value);
   } else {
     ASSERT((raw_ptr()->data_ == Object::null()) || value.IsNull());
     set_data(value);
   }
 }
 
 
+RawType* Function::ExistingSignatureType() const {
+  const Object& obj = Object::Handle(raw_ptr()->data_);
+  ASSERT(!obj.IsNull());
+  if (IsSignatureFunction()) {
+    return SignatureData::Cast(obj).signature_type();
+  } else {
+    ASSERT(IsClosureFunction());
+    return ClosureData::Cast(obj).signature_type();
+  }
+}
+
+
 RawType* Function::SignatureType() const {
-  Type& type = Type::Handle();
-  const Object& obj = Object::Handle(raw_ptr()->data_);
-  ASSERT(!obj.IsNull());
-  if (IsSignatureFunction()) {
-    type = SignatureData::Cast(obj).signature_type();
-  } else {
-    ASSERT(IsClosureFunction());
-    type = ClosureData::Cast(obj).signature_type();
-  }
+  Type& type = Type::Handle(ExistingSignatureType());
   if (type.IsNull()) {
     // The function type of this function is not yet cached and needs to be
     // constructed and cached here.
     // A function type is type parameterized in the same way as the owner class
     // of its non-static signature function.
     // It is not type parameterized if its signature function is static, or if
     // none of its result type or formal parameter types are type parameterized.
     // Unless the function type is a generic typedef, the type arguments of the
     // function type are not explicitly stored in the function type as a vector
     // of type arguments.
@@ skipping 17510 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart