Equality can be converted to a strict equality with checks. If the number of checks exceeds the thr…

runtime/vm/intermediate_language.cc

Index: runtime/vm/intermediate_language.cc
===================================================================
--- runtime/vm/intermediate_language.cc	(revision 24590)
+++ runtime/vm/intermediate_language.cc	(working copy)
@@ -21,6 +21,9 @@
 
 namespace dart {
 
+DEFINE_FLAG(int, max_equality_polymorphic_checks, 32,
+    "Maximum number of polymorphic checks in equality operator,"
+    " otherwise use megamorphic dispatch.");
 DEFINE_FLAG(bool, new_identity_spec, true,
     "Use new identity check rules for numbers.");
 DEFINE_FLAG(bool, propagate_ic_data, true,
@@ -1034,6 +1037,14 @@
 }
 
 
+bool EqualityCompareInstr::IsCheckedStrictEqual() const {
+  if (!HasICData()) return false;
+  return ic_data()->AllTargetsHaveSameOwner(kInstanceCid) &&
+         (unary_ic_data_->NumberOfChecks() <=
+             FLAG_max_equality_polymorphic_checks);
+}
+
+
 bool BinarySmiOpInstr::CanDeoptimize() const {
   if (FLAG_throw_on_javascript_int_overflow) return true;
   switch (op_kind()) {