[turbofan] Introduce JSCallForwardVarargs operator.

src/interface-descriptors.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_CALL_INTERFACE_DESCRIPTOR_H_
 #define V8_CALL_INTERFACE_DESCRIPTOR_H_
 
 #include <memory>
 
 #include "src/assembler.h"
@@ skipping 28 matching lines @@
   V(TypeConversion)                       \
   V(Typeof)                               \
   V(FastCloneRegExp)                      \
   V(FastCloneShallowArray)                \
   V(FastCloneShallowObject)               \
   V(CreateAllocationSite)                 \
   V(CreateWeakCell)                       \
   V(CallFunction)                         \
   V(CallFunctionWithFeedback)             \
   V(CallFunctionWithFeedbackAndVector)    \
+  V(CallForwardVarargs)                   \
   V(CallConstruct)                        \
   V(CallTrampoline)                       \
   V(ConstructStub)                        \
   V(ConstructTrampoline)                  \
   V(RegExpExec)                           \
   V(CopyFastSmiOrObjectElements)          \
   V(TransitionElementsKind)               \
   V(AllocateHeapNumber)                   \
   V(AllocateFloat32x4)                    \
   V(AllocateInt32x4)                      \
@@ skipping 494 matching lines @@
 };
 
 
 class CallTrampolineDescriptor : public CallInterfaceDescriptor {
  public:
   DEFINE_PARAMETERS(kFunction, kActualArgumentsCount)
   DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(CallTrampolineDescriptor,
                                                CallInterfaceDescriptor)
 };
 
+class CallForwardVarargsDescriptor : public CallInterfaceDescriptor {
+ public:
+  DEFINE_PARAMETERS(kTarget, kStartIndex)
+  DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(CallForwardVarargsDescriptor,
+                                               CallInterfaceDescriptor)
+};
 
 class ConstructStubDescriptor : public CallInterfaceDescriptor {
  public:
   DEFINE_PARAMETERS(kFunction, kNewTarget, kActualArgumentsCount,
                     kAllocationSite)
   DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(ConstructStubDescriptor,
                                                CallInterfaceDescriptor)
 };
 
 
@@ skipping 326 matching lines @@
 }  // namespace v8
 
 
 #if V8_TARGET_ARCH_ARM64
 #include "src/arm64/interface-descriptors-arm64.h"
 #elif V8_TARGET_ARCH_ARM
 #include "src/arm/interface-descriptors-arm.h"
 #endif
 
 #endif  // V8_CALL_INTERFACE_DESCRIPTOR_H_