Remove signature classes from the VM.

runtime/vm/intrinsifier_ia32.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.
 //
 // The intrinsic code below is executed before a method has built its frame.
 // The return address is on the stack and the arguments below it.
 // Registers EDX (arguments descriptor) and ECX (function) must be preserved.
 // Each intrinsification method returns true if the corresponding
 // Dart method was intrinsified.
 
@@ skipping 1662 matching lines @@
   __ LoadObject(EAX, Bool::True());
   __ ret();
 }
 
 
 // Return type quickly for simple types (not parameterized and not signature).
 void Intrinsifier::ObjectRuntimeType(Assembler* assembler) {
   Label fall_through;
   __ movl(EAX, Address(ESP, + 1 * kWordSize));
   __ LoadClassIdMayBeSmi(EDI, EAX);
+  __ cmpl(EDI, Immediate(kClosureCid));
+  __ j(EQUAL, &fall_through, Assembler::kNearJump);  // Instance is a closure.
   __ LoadClassById(EBX, EDI);
   // EBX: class of instance (EAX).
-  const Immediate& raw_null =
-      Immediate(reinterpret_cast<intptr_t>(Object::null()));
-  __ movl(EDI, FieldAddress(EBX, Class::signature_function_offset()));
-  __ cmpl(EDI, raw_null);
-  __ j(NOT_EQUAL, &fall_through, Assembler::kNearJump);
 
   __ movzxw(EDI, FieldAddress(EBX, Class::num_type_arguments_offset()));
   __ cmpl(EDI, Immediate(0));
   __ j(NOT_EQUAL, &fall_through, Assembler::kNearJump);
   __ movl(EAX, FieldAddress(EBX, Class::canonical_types_offset()));
-  __ cmpl(EAX, raw_null);
+  __ CompareObject(EAX, Object::null_object());
   __ j(EQUAL, &fall_through, Assembler::kNearJump);  // Not yet set.
   __ ret();
 
   __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::String_getHashCode(Assembler* assembler) {
   Label fall_through;
   __ movl(EAX, Address(ESP, + 1 * kWordSize));  // String object.
@@ skipping 447 matching lines @@
 void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
   __ LoadIsolate(EAX);
   __ movl(EAX, Address(EAX, Isolate::current_tag_offset()));
   __ ret();
 }
 
 #undef __
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32