Fix bug in instanceof stub...

src/ia32/code-stubs-ia32.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 5146 matching lines @@
 
   __ bind(&object_not_null_or_smi);
   // String values is not instance of anything.
   Condition is_string = masm->IsObjectStringType(object, scratch, scratch);
   __ j(NegateCondition(is_string), &slow);
   __ Set(eax, Immediate(Smi::FromInt(1)));
   __ ret((HasArgsInRegisters() ? 0 : 2) * kPointerSize);
 
   // Slow-case: Go through the JavaScript implementation.
   __ bind(&slow);
-  if (HasArgsInRegisters()) {
-    // Push arguments below return address.
-    __ pop(scratch);
+  if (!ReturnTrueFalseObject()) {
+    // Tail call the builtin which returns 0 or 1.
+    if (HasArgsInRegisters()) {
+      // Push arguments below return address.
+      __ pop(scratch);
+      __ push(object);
+      __ push(function);
+      __ push(scratch);
+    }
+    __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
+  } else {
+    // Call the builtin and convert 0/1 to true/false.
     __ push(object);
     __ push(function);
-    __ push(scratch);
+    __ InvokeBuiltin(Builtins::INSTANCE_OF, CALL_FUNCTION);
+    NearLabel true_value, done;
+    __ test(eax, Operand(eax));
+    __ j(zero, &true_value);
+    __ mov(eax, Factory::false_value());
+    __ jmp(&done);
+    __ bind(&true_value);
+    __ mov(eax, Factory::true_value());
+    __ bind(&done);
+    __ ret((HasArgsInRegisters() ? 0 : 2) * kPointerSize);
   }
-  __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
 }
 
 
 Register InstanceofStub::left() { return eax; }
 
 
 Register InstanceofStub::right() { return edx; }
 
 
 int CompareStub::MinorKey() {
@@ skipping 1304 matching lines @@
   // Do a tail call to the rewritten stub.
   __ jmp(Operand(edi));
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32