[Interpreter] Add support for JS calls.

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 106 matching lines @@
 
   enum Flag {
     kNoFlags = 0u,
     kNeedsFrameState = 1u << 0,
     kPatchableCallSite = 1u << 1,
     kNeedsNopAfterCall = 1u << 2,
     kHasExceptionHandler = 1u << 3,
     kHasLocalCatchHandler = 1u << 4,
     kSupportsTailCalls = 1u << 5,
     kCanUseRoots = 1u << 6,
+    kHasVarArgs = 1u << 7,
     kPatchableCallSiteWithNop = kPatchableCallSite | kNeedsNopAfterCall
   };
   typedef base::Flags<Flag> Flags;
 
   CallDescriptor(Kind kind, MachineType target_type, LinkageLocation target_loc,
                  const MachineSignature* machine_sig,
                  LocationSignature* location_sig, size_t stack_param_count,
                  Operator::Properties properties,
                  RegList callee_saved_registers,
                  RegList callee_saved_fp_registers, Flags flags,
@@ skipping 37 matching lines @@
     return stack_param_count_;
   }
 
   // The total number of inputs to this call, which includes the target,
   // receiver, context, etc.
   // TODO(titzer): this should input the framestate input too.
   size_t InputCount() const { return 1 + machine_sig_->parameter_count(); }
 
   size_t FrameStateCount() const { return NeedsFrameState() ? 1 : 0; }
 
+  size_t VarArgsInputCount() const { return HasVarArgs() ? 2 : 0; }
+
   Flags flags() const { return flags_; }
 
   bool NeedsFrameState() const { return flags() & kNeedsFrameState; }
   bool SupportsTailCalls() const { return flags() & kSupportsTailCalls; }
+  bool HasVarArgs() const { return flags() & kHasVarArgs; }
 
   LinkageLocation GetReturnLocation(size_t index) const {
     return location_sig_->GetReturn(index);
   }
 
   LinkageLocation GetInputLocation(size_t index) const {
     if (index == 0) return target_loc_;
     return location_sig_->GetParam(index - 1);
   }
 
@@ skipping 143 matching lines @@
   CallDescriptor* const incoming_;
 
   DISALLOW_COPY_AND_ASSIGN(Linkage);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_LINKAGE_H_