VM: Make precompiler process constants/fields only once, avoid using pool.InfoAt()

runtime/vm/object.h

 // 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.
 
 #ifndef RUNTIME_VM_OBJECT_H_
 #define RUNTIME_VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 8637 matching lines @@
 
   void set_label(const String& tag_label) const {
     StorePointer(&raw_ptr()->label_, tag_label.raw());
   }
 
   FINAL_HEAP_OBJECT_IMPLEMENTATION(UserTag, Instance);
   friend class Class;
 };
 
 
+class ObjectPoolInfo {

[Florian Schneider, 2016/12/08 18:30:45]

: public ValueObject

[kustermann, 2016/12/08 19:14:38]

Done.

+ public:
+  explicit ObjectPoolInfo(const ObjectPool& pool)
+      : array_(TypedData::Handle(pool.info_array())) {}
+
+  explicit ObjectPoolInfo(const TypedData& info_array) : array_(info_array) {}

[Florian Schneider, 2016/12/08 18:30:45]

Not needed?

[kustermann, 2016/12/08 19:14:38]

See comment on call site. Using this constructor means one can re-use a
[TypedData] handle when looping over many different functions.

+
+  ObjectPool::EntryType InfoAt(intptr_t i) {
+    return static_cast<ObjectPool::EntryType>(array_.GetInt8(i));
+  }
+
+  void SetInfoAt(intptr_t i, ObjectPool::EntryType info) {
+    array_.SetInt8(i, static_cast<int8_t>(info));
+  }
+
+ private:
+  const TypedData& array_;
+};
+
+
 // Breaking cycles and loops.
 RawClass* Object::clazz() const {
   uword raw_value = reinterpret_cast<uword>(raw_);
   if ((raw_value & kSmiTagMask) == kSmiTag) {
     return Smi::Class();
   }
   return Isolate::Current()->class_table()->At(raw()->GetClassId());
 }
 
 
@@ skipping 198 matching lines @@
 
 inline void TypeArguments::SetHash(intptr_t value) const {
   // This is only safe because we create a new Smi, which does not cause
   // heap allocation.
   StoreSmi(&raw_ptr()->hash_, Smi::New(value));
 }
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_OBJECT_H_