PPC/s390: [turbofan] Introduce JSCallForwardVarargs operator.

src/ppc/interface-descriptors-ppc.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.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/interface-descriptors.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 156 matching lines @@
 
 
 void CallTrampolineDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // r3 : number of arguments
   // r4 : the target to call
   Register registers[] = {r4, r3};
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
+void CallForwardVarargsDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  // r5 : start index (to support rest parameters)
+  // r4 : the target to call
+  Register registers[] = {r4, r5};
+  data->InitializePlatformSpecific(arraysize(registers), registers);
+}
 
 void ConstructStubDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // r3 : number of arguments
   // r4 : the target to call
   // r6 : the new target
   // r5 : allocation site or undefined
   Register registers[] = {r4, r6, r3, r5};
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
@@ skipping 215 matching lines @@
       r3,  // the value to pass to the generator
       r4,  // the JSGeneratorObject to resume
       r5   // the resume mode (tagged)
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_PPC