Merged r17599 into 3.21 branch.

src/hydrogen.h

Index: src/hydrogen.h
diff --git a/src/hydrogen.h b/src/hydrogen.h
index c1dafa8b5a7a73171c3c6c693f60210656ccac27..0ecbbca1bf66cc24f80b614fbfd406fa9cedd4ea 100644
--- a/src/hydrogen.h
+++ b/src/hydrogen.h
@@ -333,9 +333,9 @@ class HGraph V8_FINAL : public ZoneObject {
   void CollectPhis();
 
   void set_undefined_constant(HConstant* constant) {
-    undefined_constant_.set(constant);
+    constant_undefined_.set(constant);
   }
-  HConstant* GetConstantUndefined() const { return undefined_constant_.get(); }
+  HConstant* GetConstantUndefined() const { return constant_undefined_.get(); }
   HConstant* GetConstant0();
   HConstant* GetConstant1();
   HConstant* GetConstantMinus1();
@@ -345,6 +345,14 @@ class HGraph V8_FINAL : public ZoneObject {
   HConstant* GetConstantNull();
   HConstant* GetInvalidContext();
 
+  bool IsConstantUndefined(HConstant* constant);
+  bool IsConstant0(HConstant* constant);
+  bool IsConstant1(HConstant* constant);
+  bool IsConstantMinus1(HConstant* constant);
+  bool IsConstantTrue(HConstant* constant);
+  bool IsConstantFalse(HConstant* constant);
+  bool IsConstantHole(HConstant* constant);
+  bool IsConstantNull(HConstant* constant);
   bool IsStandardConstant(HConstant* constant);
 
   HBasicBlock* CreateBasicBlock();
@@ -359,6 +367,7 @@ class HGraph V8_FINAL : public ZoneObject {
   int GetMaximumValueID() const { return values_.length(); }
   int GetNextBlockID() { return next_block_id_++; }
   int GetNextValueID(HValue* value) {
+    ASSERT(!disallow_adding_new_values_);
     values_.Add(value, zone());
     return values_.length() - 1;
   }
@@ -366,6 +375,9 @@ class HGraph V8_FINAL : public ZoneObject {
     if (id >= 0 && id < values_.length()) return values_[id];
     return NULL;
   }
+  void DisallowAddingNewValues() {
+    disallow_adding_new_values_ = true;
+  }
 
   bool Optimize(BailoutReason* bailout_reason);
 
@@ -477,7 +489,7 @@ class HGraph V8_FINAL : public ZoneObject {
   ZoneList<HValue*> values_;
   ZoneList<HPhi*>* phi_list_;
   ZoneList<HInstruction*>* uint32_instructions_;
-  SetOncePointer<HConstant> undefined_constant_;
+  SetOncePointer<HConstant> constant_undefined_;
   SetOncePointer<HConstant> constant_0_;
   SetOncePointer<HConstant> constant_1_;
   SetOncePointer<HConstant> constant_minus1_;
@@ -500,6 +512,7 @@ class HGraph V8_FINAL : public ZoneObject {
   int type_change_checksum_;
   int maximum_environment_size_;
   int no_side_effects_scope_count_;
+  bool disallow_adding_new_values_;
 
   DISALLOW_COPY_AND_ASSIGN(HGraph);
 };