Sped up hashCode by removing megamorphic call to _identityHashCode.

runtime/vm/jit_optimizer.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/jit_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/branch_optimizer.h"
 #include "vm/cha.h"
 #include "vm/compiler.h"
@@ skipping 2314 matching lines @@
     TryAddTest(results, kMintCid, true);
     TryAddTest(results, kBigintCid, true);
     // Cannot deoptimize since all tests returning true have been added.
     return false;
   }
 
   return true;  // May deoptimize since we have not identified all 'true' tests.
 }
 
 
+// Tells whether the function of the call matches the core private name.
+static bool matches_core(InstanceCallInstr* call, const String& name) {
+  return call->function_name().raw() == Library::PrivateCoreLibName(name).raw();
+}
+
+
 // TODO(srdjan): Use ICData to check if always true or false.
 void JitOptimizer::ReplaceWithInstanceOf(InstanceCallInstr* call) {
   ASSERT(Token::IsTypeTestOperator(call->token_kind()));
   Definition* left = call->ArgumentAt(0);
   Definition* type_args = NULL;
   AbstractType& type = AbstractType::ZoneHandle(Z);
   bool negate = false;
   if (call->ArgumentCount() == 2) {
     type_args = flow_graph()->constant_null();
-    if (call->function_name().raw() ==
-        Library::PrivateCoreLibName(Symbols::_instanceOfNum()).raw()) {
-      type = Type::Number();
-    } else if (call->function_name().raw() ==
-        Library::PrivateCoreLibName(Symbols::_instanceOfInt()).raw()) {
-      type = Type::IntType();
-    } else if (call->function_name().raw() ==
-        Library::PrivateCoreLibName(Symbols::_instanceOfSmi()).raw()) {
-      type = Type::SmiType();
-    } else if (call->function_name().raw() ==
-        Library::PrivateCoreLibName(Symbols::_instanceOfDouble()).raw()) {
-      type = Type::Double();
-    } else if (call->function_name().raw() ==
-        Library::PrivateCoreLibName(Symbols::_instanceOfString()).raw()) {
-      type = Type::StringType();
+    if (matches_core(call, Symbols::_simpleInstanceOf())) {
+      type =
+          AbstractType::Cast(call->ArgumentAt(1)->AsConstant()->value()).raw();
+      negate = false;  // Just to be sure.
     } else {
-      UNIMPLEMENTED();
+      if (matches_core(call, Symbols::_instanceOfNum())) {
+        type = Type::Number();
+      } else if (matches_core(call, Symbols::_instanceOfInt())) {
+        type = Type::IntType();
+      } else if (matches_core(call, Symbols::_instanceOfSmi())) {
+        type = Type::SmiType();
+      } else if (matches_core(call, Symbols::_instanceOfDouble())) {
+        type = Type::Double();
+      } else if (matches_core(call, Symbols::_instanceOfString())) {
+        type = Type::StringType();
+      } else {
+        UNIMPLEMENTED();
+      }
+      negate = Bool::Cast(call->ArgumentAt(1)->OriginalDefinition()
+                          ->AsConstant()->value()).value();
     }
-    negate = Bool::Cast(call->ArgumentAt(1)->OriginalDefinition()
-        ->AsConstant()->value()).value();
   } else {
     type_args = call->ArgumentAt(1);
     type = AbstractType::Cast(call->ArgumentAt(2)->AsConstant()->value()).raw();
     negate = Bool::Cast(call->ArgumentAt(3)->OriginalDefinition()
         ->AsConstant()->value()).value();
   }
   const ICData& unary_checks =
       ICData::ZoneHandle(Z, call->ic_data()->AsUnaryClassChecks());
   if ((unary_checks.NumberOfChecks() > 0) &&
       (unary_checks.NumberOfChecks() <= FLAG_max_polymorphic_checks)) {
@@ skipping 568 matching lines @@
 
   // Discard the environment from the original instruction because the store
   // can't deoptimize.
   instr->RemoveEnvironment();
   ReplaceCall(instr, store);
   return true;
 }
 
 
 }  // namespace dart