[ic] Support data handlers that represent loads from prototypes.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index eb8416d45fada5a573553837ee741f9be8bc545c..3d92e6d7122ce9cc48389d561f46e54ce2a03afe 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -400,6 +400,7 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(BOX_TYPE)                                                   \
   V(PROMISE_CONTAINER_TYPE)                                     \
   V(PROTOTYPE_INFO_TYPE)                                        \
+  V(TUPLE3_TYPE)                                                \
   V(CONTEXT_EXTENSION_TYPE)                                     \
   V(MODULE_TYPE)                                                \
                                                                 \
@@ -521,6 +522,7 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(DEBUG_INFO, DebugInfo, debug_info)                                       \
   V(BREAK_POINT_INFO, BreakPointInfo, break_point_info)                      \
   V(PROTOTYPE_INFO, PrototypeInfo, prototype_info)                           \
+  V(TUPLE3, Tuple3, tuple3)                                                  \
   V(MODULE, Module, module)                                                  \
   V(CONTEXT_EXTENSION, ContextExtension, context_extension)
 
@@ -697,6 +699,7 @@ enum InstanceType {
   TRANSITION_ARRAY_TYPE,
   PROPERTY_CELL_TYPE,
   PROTOTYPE_INFO_TYPE,
+  TUPLE3_TYPE,
   CONTEXT_EXTENSION_TYPE,
   MODULE_TYPE,
 
@@ -6782,6 +6785,26 @@ class PrototypeInfo : public Struct {
   DISALLOW_IMPLICIT_CONSTRUCTORS(PrototypeInfo);
 };
 
+class Tuple3 : public Struct {

[Jakob Kummerow, 2016/10/13 11:59:26]

I would have called it Triple (and the values maybe x, y, z?), but Tuple3 is
fine too.

[Igor Sheludko, 2016/10/13 13:20:38]

Let's keep it in a form TupleX because it scales (we will probably need Tuple4
for transitioning stores). 

+ public:
+  DECL_ACCESSORS(value1, Object)
+  DECL_ACCESSORS(value2, Object)
+  DECL_ACCESSORS(value3, Object)
+
+  DECLARE_CAST(Tuple3)
+
+  // Dispatched behavior.
+  DECLARE_PRINTER(Tuple3)
+  DECLARE_VERIFIER(Tuple3)
+
+  static const int kValue1Offset = HeapObject::kHeaderSize;
+  static const int kValue2Offset = kValue1Offset + kPointerSize;
+  static const int kValue3Offset = kValue2Offset + kPointerSize;
+  static const int kSize = kValue3Offset + kPointerSize;
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(Tuple3);
+};
 
 // Pair used to store both a ScopeInfo and an extension object in the extension
 // slot of a block, catch, or with context. Needed in the rare case where a