Keep a trail while checking upper bounds in the VM in order to properly handle

runtime/vm/flow_graph_compiler_x64.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.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 260 matching lines @@
     const AbstractType& type,
     Label* is_instance_lbl,
     Label* is_not_instance_lbl) {
   __ Comment("InstantiatedTypeWithArgumentsTest");
   ASSERT(type.IsInstantiated());
   const Class& type_class = Class::ZoneHandle(zone(), type.type_class());
   ASSERT(type.IsFunctionType() || (type_class.NumTypeArguments() > 0));
   const Register kInstanceReg = RAX;
   Error& bound_error = Error::Handle(zone());
   const Type& int_type = Type::Handle(zone(), Type::IntType());
-  const bool smi_is_ok = int_type.IsSubtypeOf(type, &bound_error, Heap::kOld);
+  const bool smi_is_ok =
+      int_type.IsSubtypeOf(type, &bound_error, NULL, Heap::kOld);
   // Malformed type should have been handled at graph construction time.
   ASSERT(smi_is_ok || bound_error.IsNull());
   __ testq(kInstanceReg, Immediate(kSmiTagMask));
   if (smi_is_ok) {
     __ j(ZERO, is_instance_lbl);
   } else {
     __ j(ZERO, is_not_instance_lbl);
   }
   // A function type test requires checking the function signature.
   if (!type.IsFunctionType()) {
@@ skipping 19 matching lines @@
     }
     // If one type argument only, check if type argument is Object or dynamic.
     if (type_arguments.Length() == 1) {
       const AbstractType& tp_argument = AbstractType::ZoneHandle(zone(),
           type_arguments.TypeAt(0));
       ASSERT(!tp_argument.IsMalformed());
       if (tp_argument.IsType()) {
         ASSERT(tp_argument.HasResolvedTypeClass());
         // Check if type argument is dynamic or Object.
         const Type& object_type = Type::Handle(zone(), Type::ObjectType());
-        if (object_type.IsSubtypeOf(tp_argument, NULL, Heap::kOld)) {
+        if (object_type.IsSubtypeOf(tp_argument, NULL, NULL, Heap::kOld)) {
           // Instance class test only necessary.
           return GenerateSubtype1TestCacheLookup(
               token_pos, type_class, is_instance_lbl, is_not_instance_lbl);
         }
       }
     }
   }
   // Regular subtype test cache involving instance's type arguments.
   const Register kTypeArgumentsReg = kNoRegister;
   const Register kTempReg = R10;
@@ skipping 38 matching lines @@
   ASSERT(type_class.NumTypeArguments() == 0);
 
   const Register kInstanceReg = RAX;
   __ testq(kInstanceReg, Immediate(kSmiTagMask));
   // If instance is Smi, check directly.
   const Class& smi_class = Class::Handle(zone(), Smi::Class());
   if (smi_class.IsSubtypeOf(TypeArguments::Handle(zone()),
                             type_class,
                             TypeArguments::Handle(zone()),
                             NULL,
+                            NULL,
                             Heap::kOld)) {
     __ j(ZERO, is_instance_lbl);
   } else {
     __ j(ZERO, is_not_instance_lbl);
   }
   // Compare if the classes are equal.
   const Register kClassIdReg = R10;
   __ LoadClassId(kClassIdReg, kInstanceReg);
   __ cmpl(kClassIdReg, Immediate(type_class.id()));
   __ j(EQUAL, is_instance_lbl);
   // See ClassFinalizer::ResolveSuperTypeAndInterfaces for list of restricted
   // interfaces.
   // Bool interface can be implemented only by core class Bool.
   if (type.IsBoolType()) {
     __ cmpl(kClassIdReg, Immediate(kBoolCid));
     __ j(EQUAL, is_instance_lbl);
     __ jmp(is_not_instance_lbl);
     return false;
   }
   if (type.IsDartFunctionType()) {
     // Check if instance is a closure.
     __ cmpq(kClassIdReg, Immediate(kClosureCid));
     __ j(EQUAL, is_instance_lbl);
   }
   // Custom checking for numbers (Smi, Mint, Bigint and Double).
   // Note that instance is not Smi (checked above).
   if (type.IsSubtypeOf(
-      Type::Handle(zone(), Type::Number()), NULL, Heap::kOld)) {
+      Type::Handle(zone(), Type::Number()), NULL, NULL, Heap::kOld)) {
     GenerateNumberTypeCheck(
         kClassIdReg, type, is_instance_lbl, is_not_instance_lbl);
     return false;
   }
   if (type.IsStringType()) {
     GenerateStringTypeCheck(kClassIdReg, is_instance_lbl, is_not_instance_lbl);
     return false;
   }
   // Otherwise fallthrough.
   return true;
@@ skipping 1395 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(kFpuRegisterSize));
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64