[strong] Implement strong mode restrictions on property access

src/ic/ic-state.h

Index: src/ic/ic-state.h
diff --git a/src/ic/ic-state.h b/src/ic/ic-state.h
index dbc504bf6d79f9f95d6a86e14eca0514198507f5..4df355db9022a4c69d8709c68dab23c6d0e16bee 100644
--- a/src/ic/ic-state.h
+++ b/src/ic/ic-state.h
@@ -201,11 +201,20 @@ class CompareICState {
 
 
 class LoadICState final BASE_EMBEDDED {
+ private:
+  class ContextualModeBits : public BitField<ContextualMode, 0, 1> {};

[Toon Verwaest, 2015/06/09 11:58:04]

Why was this moved up? That looks odd...

[conradw, 2015/06/09 13:09:27]

Because of the initialisation order, if I want to be able to have a static
member kStrongModeState inititalised using the bitfield then the bitfield needs
to be declared first.

In StoreICState where something similar is done, the bitfield is declared as
public, in an order which gets around this. Not sure which is better.

+  class StrengthBits : public BitField<bool, 1, 1> {};
+  STATIC_ASSERT(static_cast<int>(NOT_CONTEXTUAL) == 0);
+  const ExtraICState state_;
+
  public:
+  static const ExtraICState kStrongModeState = 1 << StrengthBits::kShift;
+
   explicit LoadICState(ExtraICState extra_ic_state) : state_(extra_ic_state) {}
 
-  explicit LoadICState(ContextualMode mode)
-      : state_(ContextualModeBits::encode(mode)) {}
+  explicit LoadICState(ContextualMode mode, Strength strength)
+      : state_(ContextualModeBits::encode(mode) |
+               StrengthBits::encode(is_strong(strength))) {}
 
   ExtraICState GetExtraICState() const { return state_; }
 
@@ -213,15 +222,17 @@ class LoadICState final BASE_EMBEDDED {
     return ContextualModeBits::decode(state_);
   }
 
+  Strength strength() const {
+    return StrengthBits::decode(state_) ? Strength::STRONG : Strength::WEAK;
+  }
+
   static ContextualMode GetContextualMode(ExtraICState state) {
     return LoadICState(state).contextual_mode();
   }
 
- private:
-  class ContextualModeBits : public BitField<ContextualMode, 0, 1> {};
-  STATIC_ASSERT(static_cast<int>(NOT_CONTEXTUAL) == 0);
-
-  const ExtraICState state_;
+  static Strength GetStrength(ExtraICState state) {
+    return LoadICState(state).strength();
+  }
 };