VectorICs: Create a StoreICState to more easily create matching code stubs.

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 76c0155206b813531f6ea2a625b3ec36b01c5739..e451fb2c80c2299b5b9695ffd52821b516789f9c 100644
--- a/src/ic/ic-state.h
+++ b/src/ic/ic-state.h
@@ -224,6 +224,36 @@ class LoadICState final BASE_EMBEDDED {
 
   const ExtraICState state_;
 };
+
+
+class StoreICState final BASE_EMBEDDED {
+ public:
+  explicit StoreICState(ExtraICState extra_ic_state) : state_(extra_ic_state) {}
+
+  explicit StoreICState(LanguageMode mode)
+      : state_(LanguageModeState::encode(mode)) {}
+
+  ExtraICState GetExtraICState() const { return state_; }
+
+  LanguageMode language_mode() const {
+    return LanguageModeState::decode(state_);
+  }
+
+  static LanguageMode GetLanguageMode(ExtraICState state) {
+    return StoreICState(state).language_mode();
+  }
+
+  class LanguageModeState : public BitField<LanguageMode, 1, 2> {};
+  STATIC_ASSERT(i::LANGUAGE_END == 3);
+
+  // For convenience, a statically declared encoding of strict mode extra
+  // IC state.
+  static const ExtraICState kStrictModeState = STRICT
+                                               << LanguageModeState::kShift;
+
+ private:
+  const ExtraICState state_;
+};
 }
 }