Check for a passed-in type argument vector in the prolog of generic functions.

runtime/vm/stub_code_arm64.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 878 matching lines @@
   __ Push(R6);
   __ LoadFromOffset(R6, THR, Thread::top_exit_frame_info_offset());
   __ StoreToOffset(ZR, THR, Thread::top_exit_frame_info_offset());
   // kExitLinkSlotFromEntryFp must be kept in sync with the code below.
   ASSERT(kExitLinkSlotFromEntryFp == -22);
   __ Push(R6);
 
   // Load arguments descriptor array into R4, which is passed to Dart code.
   __ LoadFromOffset(R4, R1, VMHandles::kOffsetOfRawPtrInHandle);
 
+  // No need to check for type args, disallowed by DartEntry::InvokeFunction.
   // Load number of arguments into S5.
   __ LoadFieldFromOffset(R5, R4, ArgumentsDescriptor::count_offset());
   __ SmiUntag(R5);
 
   // Compute address of 'arguments array' data area into R2.
   __ LoadFromOffset(R2, R2, VMHandles::kOffsetOfRawPtrInHandle);
   __ AddImmediate(R2, Array::data_offset() - kHeapObjectTag);
 
   // Set up arguments for the Dart call.
   Label push_arguments;
@@ skipping 1467 matching lines @@
 }
 
 
 void StubCode::GenerateAsynchronousGapMarkerStub(Assembler* assembler) {
   __ brk(0);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64