[turbofan] Avoid allocating rest parameters for spread calls.

src/compiler/js-generic-lowering.cc

Index: src/compiler/js-generic-lowering.cc
diff --git a/src/compiler/js-generic-lowering.cc b/src/compiler/js-generic-lowering.cc
index 9f240c5a9b66f6d4a79e7c3da80ccf1cd2a36898..4cd53210d0150c44c677da04e2e89bc442b70f24 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -523,6 +523,28 @@ void JSGenericLowering::LowerJSCreateScriptContext(Node* node) {
   ReplaceWithRuntimeCall(node, Runtime::kNewScriptContext);
 }
 
+void JSGenericLowering::LowerJSConstructForwardVarargs(Node* node) {
+  ConstructForwardVarargsParameters p =
+      ConstructForwardVarargsParametersOf(node->op());
+  int const arg_count = static_cast<int>(p.arity() - 2);
+  CallDescriptor::Flags flags = FrameStateFlagForCall(node);
+  Callable callable = CodeFactory::ConstructForwardVarargs(isolate());
+  CallDescriptor* desc = Linkage::GetStubCallDescriptor(
+      isolate(), zone(), callable.descriptor(), arg_count + 1, flags);
+  Node* stub_code = jsgraph()->HeapConstant(callable.code());
+  Node* stub_arity = jsgraph()->Int32Constant(arg_count);
+  Node* start_index = jsgraph()->Uint32Constant(p.start_index());
+  Node* new_target = node->InputAt(arg_count + 1);
+  Node* receiver = jsgraph()->UndefinedConstant();
+  node->RemoveInput(arg_count + 1);  // Drop new target.
+  node->InsertInput(zone(), 0, stub_code);
+  node->InsertInput(zone(), 2, new_target);
+  node->InsertInput(zone(), 3, stub_arity);
+  node->InsertInput(zone(), 4, start_index);
+  node->InsertInput(zone(), 5, receiver);
+  NodeProperties::ChangeOp(node, common()->Call(desc));
+}
+
 void JSGenericLowering::LowerJSConstruct(Node* node) {
   ConstructParameters const& p = ConstructParametersOf(node->op());
   int const arg_count = static_cast<int>(p.arity() - 2);
@@ -563,17 +585,20 @@ void JSGenericLowering::LowerJSConstructWithSpread(Node* node) {
 
 void JSGenericLowering::LowerJSCallForwardVarargs(Node* node) {
   CallForwardVarargsParameters p = CallForwardVarargsParametersOf(node->op());
-  Callable callable = CodeFactory::CallForwardVarargs(isolate());
+  int const arg_count = static_cast<int>(p.arity() - 2);
   CallDescriptor::Flags flags = FrameStateFlagForCall(node);
+  Callable callable = CodeFactory::CallForwardVarargs(isolate());
   if (p.tail_call_mode() == TailCallMode::kAllow) {
     flags |= CallDescriptor::kSupportsTailCalls;
   }
   CallDescriptor* desc = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), callable.descriptor(), 1, flags);
+      isolate(), zone(), callable.descriptor(), arg_count + 1, flags);
   Node* stub_code = jsgraph()->HeapConstant(callable.code());
+  Node* stub_arity = jsgraph()->Int32Constant(arg_count);
   Node* start_index = jsgraph()->Uint32Constant(p.start_index());
   node->InsertInput(zone(), 0, stub_code);
-  node->InsertInput(zone(), 2, start_index);
+  node->InsertInput(zone(), 2, stub_arity);
+  node->InsertInput(zone(), 3, start_index);
   NodeProperties::ChangeOp(node, common()->Call(desc));
 }