[interpreter, debugger] abstraction for source position calculation.

src/runtime/runtime-generator.cc

 // Copyright 2014 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.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/factory.h"
 #include "src/frames-inl.h"
 #include "src/objects-inl.h"
@@ skipping 177 matching lines @@
 
 
 RUNTIME_FUNCTION(Runtime_GeneratorGetSourcePosition) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, generator, 0);
 
   if (generator->is_suspended()) {
     Handle<Code> code(generator->function()->code(), isolate);
     int offset = generator->continuation();
-
-    RUNTIME_ASSERT(0 <= offset && offset < code->Size());
-    Address pc = code->address() + offset;
-
-    return Smi::FromInt(code->SourcePosition(pc));
+    RUNTIME_ASSERT(0 <= offset && offset < code->instruction_size());
+    return Smi::FromInt(code->SourcePosition(offset));
   }
 
   return isolate->heap()->undefined_value();
 }
 
 
 RUNTIME_FUNCTION(Runtime_GeneratorNext) {
   UNREACHABLE();  // Optimization disabled in SetUpGenerators().
   return NULL;
 }
 
 
 RUNTIME_FUNCTION(Runtime_GeneratorThrow) {
   UNREACHABLE();  // Optimization disabled in SetUpGenerators().
   return NULL;
 }
 }  // namespace internal
 }  // namespace v8