Using array index hash code for string-to-number conversion.

src/x64/full-codegen-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2579 matching lines @@
   __ Move(rax, Factory::false_value());
   __ jmp(&done);
   __ bind(&ok);
   __ Move(rax, Factory::true_value());
   __ bind(&done);
 
   Apply(context_, rax);
 }
 
 
+void FullCodeGenerator::EmitHasCachedArrayIndex(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+
+  VisitForValue(args->at(0), kAccumulator);
+
+  Label materialize_true, materialize_false;
+  Label* if_true = NULL;
+  Label* if_false = NULL;
+  Label* fall_through = NULL;
+  PrepareTest(&materialize_true, &materialize_false,
+              &if_true, &if_false, &fall_through);
+
+  __ testl(FieldOperand(rax, String::kHashFieldOffset),
+           Immediate(String::kContainsCachedArrayIndexMask));
+  __ j(zero, if_true);
+  __ jmp(if_false);
+
+  Apply(context_, if_true, if_false);
+}
+
+
+void FullCodeGenerator::EmitGetCachedArrayIndex(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+
+  VisitForValue(args->at(0), kAccumulator);
+
+  __ movl(rax, FieldOperand(rax, String::kHashFieldOffset));
+  ASSERT(String::kHashShift >= kSmiTagSize);
+  __ IndexFromHash(rax, rax);
+
+  Apply(context_, rax);
+}
+
+
 void FullCodeGenerator::VisitCallRuntime(CallRuntime* expr) {
   Handle<String> name = expr->name();
   if (name->length() > 0 && name->Get(0) == '_') {
     Comment cmnt(masm_, "[ InlineRuntimeCall");
     EmitInlineRuntimeCall(expr);
     return;
   }
 
   Comment cmnt(masm_, "[ CallRuntime");
   ZoneList<Expression*>* args = expr->arguments();
@@ skipping 636 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64