Add faster, but unsafe version of LoadInternalField.

src/fast-accessor-assembler.h

Index: src/fast-accessor-assembler.h
diff --git a/src/fast-accessor-assembler.h b/src/fast-accessor-assembler.h
index 41337a2b09d8883efd2243e785040da4db4bfde3..fd3e482fa5b8e602423c38954a089b220a248f21 100644
--- a/src/fast-accessor-assembler.h
+++ b/src/fast-accessor-assembler.h
@@ -54,6 +54,15 @@ class FastAccessorAssembler {
   ValueId IntegerConstant(int int_constant);
   ValueId GetReceiver();
   ValueId LoadInternalField(ValueId value_id, int field_no);
+
+  // Loads internal field and assumes the object is indeed a valid API object
+  // with the proper internal fields present.
+  // The intended use is to call this on an object whose structure has already
+  // been checked previously, e.g. the accessor's receiver, which is map-checked
+  // before the fast accessor is called on it. Using this on an arbitrary object
+  // will result in unsafe memory accesses.
+  ValueId LoadInternalFieldUnchecked(ValueId value_id, int field_no);
+
   ValueId LoadValue(ValueId value_id, int offset);
   ValueId LoadObject(ValueId value_id, int offset);
 
@@ -76,6 +85,7 @@ class FastAccessorAssembler {
   LabelId FromRaw(CodeStubAssembler::Label* label);
   compiler::Node* FromId(ValueId value) const;
   CodeStubAssembler::Label* FromId(LabelId value) const;
+  void CheckIsJSObjectOrJump(ValueId value, LabelId label_id);

[vogelheim, 2016/08/08 11:47:22]

nitpick: Maybe add empty line. The previous 4 methods are a group of closely
related functions (translating API-IDs to Node*), while this one is quite
different.

[Alfonso, 2016/08/08 13:03:28]

Acknowledged.

 
   void Clear();
   Zone* zone() { return &zone_; }