Convert 'identical' to strict equal.

runtime/vm/flow_graph_builder.cc

 // Copyright (c) 2012, 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/flow_graph_builder.h"
 
 #include "vm/ast_printer.h"
 #include "vm/code_descriptors.h"
 #include "vm/dart_entry.h"
 #include "vm/flags.h"
@@ skipping 1513 matching lines @@
       node->token_pos(),
       node->function_name(), Token::kILLEGAL, arguments,
       node->arguments()->names(), 1);
   ReturnDefinition(call);
 }
 
 
 // <Expression> ::= StaticCall { function: Function
 //                               arguments: <ArgumentList> }
 void EffectGraphVisitor::VisitStaticCallNode(StaticCallNode* node) {
+  if (node->function().name() == Symbols::Identical()) {
+    // Attempt to replace identical with strcit equal early on.
+    // TODO(hausner): Evaluate if this can happen at AST building time.
+    const Class& cls = Class::Handle(node->function().Owner());
+    if (cls.IsTopLevel()) {
+      const Library& core_lib = Library::Handle(Library::CoreLibrary());
+      if (cls.library() == core_lib.raw()) {
+        ASSERT(node->arguments()->length() == 2);
+        ValueGraphVisitor for_left_value(owner(), temp_index());
+        node->arguments()->NodeAt(0)->Visit(&for_left_value);
+        Append(for_left_value);
+        ValueGraphVisitor for_right_value(owner(), temp_index());
+        node->arguments()->NodeAt(1)->Visit(&for_right_value);
+        Append(for_right_value);
+        StrictCompareInstr* comp = new StrictCompareInstr(
+            Token::kEQ_STRICT,
+            for_left_value.value(),
+            for_right_value.value());
+        ReturnDefinition(comp);
+        return;
+      }
+    }
+  }
   ZoneGrowableArray<PushArgumentInstr*>* arguments =
       new ZoneGrowableArray<PushArgumentInstr*>(node->arguments()->length());
   BuildPushArguments(*node->arguments(), arguments);
   StaticCallInstr* call =
       new StaticCallInstr(node->token_pos(),
                           node->function(),
                           node->arguments()->names(),
                           arguments);
   ReturnDefinition(call);
 }
@@ skipping 1127 matching lines @@
   intptr_t len = OS::SNPrint(NULL, 0, kFormat, function_name, reason) + 1;
   char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
   OS::SNPrint(chars, len, kFormat, function_name, reason);
   const Error& error = Error::Handle(
       LanguageError::New(String::Handle(String::New(chars))));
   Isolate::Current()->long_jump_base()->Jump(1, error);
 }
 
 
 }  // namespace dart