DBC: Collect type feedback for fastpath smi ops

runtime/vm/object_dbc_test.cc

 // Copyright (c) 2016, 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 "platform/assert.h"
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_DBC)
 
 #include "vm/assembler.h"
 #include "vm/object.h"
 #include "vm/unit_test.h"
 
 namespace dart {
 
 #define __ assembler->
 
 // Generate a simple dart code sequence.
 // This is used to test Code and Instruction object creation.
+// For other architectures, this sequence does do an increment, hence the name.
+// On DBC, we don't do an increment because generating an instance call here
+// would be too complex.
 void GenerateIncrement(Assembler* assembler) {
   __ Frame(1);
-  __ LoadConstant(0, Smi::Handle(Smi::New(0)));
-  __ PushConstant(Smi::Handle(Smi::New(1)));
-  __ Push(0);
-  __ AddTOS();
-  __ Trap();
-  __ PopLocal(0);
+  __ LoadConstant(0, Smi::Handle(Smi::New(1)));
   __ Return(0);
 }
 
 
 // Generate a dart code sequence that embeds a string object in it.
 // This is used to test Embedded String objects in the instructions.
 void GenerateEmbedStringInCode(Assembler* assembler, const char* str) {
   const String& string_object =
       String::ZoneHandle(String::New(str, Heap::kOld));
   __ PushConstant(string_object);
   __ ReturnTOS();
 }
 
 
 // Generate a dart code sequence that embeds a smi object in it.
 // This is used to test Embedded Smi objects in the instructions.
 void GenerateEmbedSmiInCode(Assembler* assembler, intptr_t value) {
   const Smi& smi_object = Smi::ZoneHandle(Smi::New(value));
   __ PushConstant(smi_object);
   __ ReturnTOS();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_DBC