[Interpreter] Add support for calling runtime functions which return a pair.

src/code-factory.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_CODE_FACTORY_H_
 #define V8_CODE_FACTORY_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 93 matching lines @@
   static Callable Call(Isolate* isolate,
                        ConvertReceiverMode mode = ConvertReceiverMode::kAny);
   static Callable CallFunction(
       Isolate* isolate, ConvertReceiverMode mode = ConvertReceiverMode::kAny);
   static Callable Construct(Isolate* isolate);
   static Callable ConstructFunction(Isolate* isolate);
 
   static Callable InterpreterPushArgsAndCall(Isolate* isolate);
   static Callable InterpreterPushArgsAndConstruct(Isolate* isolate);
   static Callable InterpreterCEntry(Isolate* isolate);
+  static Callable InterpreterCEntryPair(Isolate* isolate);

[Michael Starzinger, 2016/01/07 17:21:28]

suggestion: What would you think about passing in the "result_size" as an
argument to InterpreterCEntry (with a default argument value of 1) instead? The
advantage I see is that callers could be parameterized, which would reduce code
duplication slightly.

[rmcilroy, 2016/01/08 14:15:06]

SGTM, done.

 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODE_FACTORY_H_