[Interpreter] Bytecode graph builder

src/compiler/linkage.h

 // 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.
 
 #ifndef V8_COMPILER_LINKAGE_H_
 #define V8_COMPILER_LINKAGE_H_
 
 #include "src/base/flags.h"
 #include "src/compiler/frame.h"
 #include "src/compiler/machine-type.h"
@@ skipping 312 matching lines @@
   LinkageLocation GetOsrValueLocation(int index) const;
 
   // A special parameter index for JSCalls that represents the closure.
   static const int kJSFunctionCallClosureParamIndex = -1;
 
   // A special {OsrValue} index to indicate the context spill slot.
   static const int kOsrContextSpillSlotIndex = -1;
 
   // Special parameter indices used to pass fixed register data through
   // interpreter dispatches.
+  static const int kInterpreterReceiverParameter = -1;

[rmcilroy, 2015/09/04 11:35:37]

No, please don't make this an Interpreter parameter - these are only the
parameters which are passed via the Dispatch TailCalls in the bytecode handler.
It should probably be just below kJSFunctionCallClosureParamIndex and be called
something like kJSFunctionRecieverParamIndex (since this is not specific to the
interpreter).

Actually, I'm wondering why this isn't 
Linkage::kJSFunctionCallClosureParamIndex - this seems to be what
ASTGraphBuilder is using for the same thing. Michi, why didn't you want this to
be Linkage::kJSFunctionCallClosureParamIndex?

[oth, 2015/09/04 16:15:46]

Removed. Won't commit until this is resolved. Comment added to
BytecodeGraphBuilder next to -1.

[Michael Starzinger, 2015/09/04 16:35:50]

Receiver and closure are to different things. One refers to whatever "this"
points to. The other refers to the JSFunction that the activation representing.

And I agree this is not a "Parameter" to the handler stub this is a "ParamIndex"
for the function activation, that's again something different.

   static const int kInterpreterAccumulatorParameter = 0;
   static const int kInterpreterRegisterFileParameter = 1;
   static const int kInterpreterBytecodeOffsetParameter = 2;
   static const int kInterpreterBytecodeArrayParameter = 3;
   static const int kInterpreterDispatchTableParameter = 4;
   static const int kInterpreterContextParameter = 5;
 
  private:
   CallDescriptor* const incoming_;
 
   DISALLOW_COPY_AND_ASSIGN(Linkage);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_LINKAGE_H_