[builtin] Adapt NewArgumentsElements with new arguments stack order

Change-Id: Ifadaffdd7e846f51accc51cc14898ddf05c98f88
Bug: v8:10201
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2214836
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68011}

src/builtins/builtins-internal-gen.cc

@@ -72,7 +72,7 @@ TF_BUILTIN(GrowFastSmiOrObjectElements, CodeStubAssembler) {
 }
 
 TF_BUILTIN(NewArgumentsElements, CodeStubAssembler) {
-  TNode<IntPtrT> frame = UncheckedCast<IntPtrT>(Parameter(Descriptor::kFrame));
+  TNode<RawPtrT> frame = UncheckedCast<RawPtrT>(Parameter(Descriptor::kFrame));
   TNode<IntPtrT> length = SmiToIntPtr(Parameter(Descriptor::kLength));
   TNode<IntPtrT> mapped_count =
       SmiToIntPtr(Parameter(Descriptor::kMappedCount));
@@ -127,10 +127,8 @@ TF_BUILTIN(NewArgumentsElements, CodeStubAssembler) {
       }
       BIND(&done_loop1);
 
-      // Compute the effective {offset} into the {frame}.
-      TNode<IntPtrT> offset = IntPtrAdd(length, IntPtrConstant(1));
-
       // Copy the parameters from {frame} (starting at {offset}) to {result}.
+      CodeStubArguments args(this, length, frame);
       Label loop2(this, &var_index), done_loop2(this);
       Goto(&loop2);
       BIND(&loop2);
@@ -142,9 +140,7 @@ TF_BUILTIN(NewArgumentsElements, CodeStubAssembler) {
         GotoIf(IntPtrEqual(index, length), &done_loop2);
 
         // Load the parameter at the given {index}.
-        TNode<Object> value = BitcastWordToTagged(
-            Load(MachineType::Pointer(), frame,
-                 TimesSystemPointerSize(IntPtrSub(offset, index))));
+        TNode<Object> value = args.AtIndex(index);
 
         // Store the {value} into the {result}.
         StoreFixedArrayElement(result, index, value, SKIP_WRITE_BARRIER);