More type checking performance improvements and a bug fix in intrinsifier.

runtime/vm/intrinsifier_ia32.cc

 // Copyright (c) 2011, 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 228 matching lines @@
         Immediate(reinterpret_cast<intptr_t>(Object::null()));
     Label checked_ok;
     __ movl(EDI, Address(ESP, + 1 * kWordSize));  // Value.
     // Null value is valid for any type.
     __ cmpl(EDI, raw_null);
     __ j(EQUAL, &checked_ok, Assembler::kNearJump);
 
     __ movl(EBX, Address(ESP, + 3 * kWordSize));  // Array.
     __ movl(EBX, FieldAddress(EBX, type_args_field_offset));
     // EBX: Type arguments of array.
+    __ cmpl(EBX, raw_null);
+    __ j(EQUAL, &checked_ok, Assembler::kNearJump);
+    // Check if it's Dynamic.
+    // For now handle only TypeArguments and bail out if InstantiatedTypeArgs.
     __ movl(EAX, FieldAddress(EBX, Object::class_offset()));
-    // Check if it's Dynamic.
-    __ cmpl(EAX, raw_null);
-    __ j(EQUAL, &checked_ok, Assembler::kNearJump);
-    // For now handle only TypeArguments and bail out if InstantiatedTypeArgs.
     __ CompareObject(EAX, Object::ZoneHandle(Object::type_arguments_class()));
     __ j(NOT_EQUAL, &fall_through, Assembler::kNearJump);
     // Get type at index 0.
     __ movl(EAX, FieldAddress(EBX, TypeArguments::type_at_offset(0)));
     __ CompareObject(EAX, Type::ZoneHandle(Type::DynamicType()));
     __ j(EQUAL,  &checked_ok, Assembler::kNearJump);
     // Check for int and num.
     __ testl(EDI, Immediate(kSmiTagMask));  // Value is Smi?
     __ j(NOT_ZERO, &fall_through, Assembler::kNearJump);  // Non-smi value.
     __ CompareObject(EAX, Type::ZoneHandle(Type::IntInterface()));
@@ skipping 1025 matching lines @@
   }                                                                            \
 
 INTRINSIC_LIST(FIND_INTRINSICS);
 #undef FIND_INTRINSICS
   return false;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32