Use CallBootstrapC stub for leaf native calls.

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/code_generator.h"
 #include "vm/compiler.h"
@@ skipping 211 matching lines @@
   __ StoreToOffset(R2, SP, argv_offset, kNoPP);
   __ StoreToOffset(R3, SP, retval_offset, kNoPP);
   __ mov(R0, SP);  // Pass the pointer to the NativeArguments.
 
   // We are entering runtime code, so the C stack pointer must be restored from
   // the stack limit to the top of the stack. We cache the stack limit address
   // in the Dart SP register, which is callee-saved in the C ABI.
   __ mov(R26, CSP);
   __ mov(CSP, SP);
 
-  // Call native function (setsup scope if not leaf function).
-  Label leaf_call;
-  Label done;
-  __ TestImmediate(R1, NativeArguments::AutoSetupScopeMask(), kNoPP);
-  __ b(&leaf_call, EQ);
-
   __ mov(R1, R5);  // Pass the function entrypoint to call.
   // Call native function invocation wrapper or redirection via simulator.
 #if defined(USING_SIMULATOR)
   uword entry = reinterpret_cast<uword>(NativeEntry::NativeCallWrapper);
   entry = Simulator::RedirectExternalReference(
       entry, Simulator::kNativeCall, NativeEntry::kNumCallWrapperArguments);
   __ LoadImmediate(R2, entry, kNoPP);
   __ blr(R2);
 #else
   __ BranchLink(&NativeEntry::NativeCallWrapperLabel(), kNoPP);
 #endif
-  __ b(&done);
 
-  __ Bind(&leaf_call);
-  // Call native function or redirection via simulator.
-  __ blr(R5);
-
-  __ Bind(&done);
   // Restore SP and CSP.
   __ mov(SP, CSP);
   __ mov(CSP, R26);
 
   // Mark that the isolate is executing Dart code.
   __ LoadImmediate(R2, VMTag::kScriptTagId, kNoPP);
   __ StoreToOffset(R2, CTX, Isolate::vm_tag_offset(), kNoPP);
 
   // Reset exit frame information in Isolate structure.
   __ StoreToOffset(ZR, CTX, Isolate::top_exit_frame_info_offset(), kNoPP);
@@ skipping 1671 matching lines @@
   const Register right = R0;
   __ LoadFromOffset(left, SP, 1 * kWordSize, kNoPP);
   __ LoadFromOffset(right, SP, 0 * kWordSize, kNoPP);
   GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64