Use CallBootstrapC stub for leaf native calls.

runtime/vm/intermediate_language_ia32.cc

 // Copyright (c) 2013, 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"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 778 matching lines @@
   locs->set_out(0, Location::RegisterLocation(EAX));
   return locs;
 }
 
 
 void NativeCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(locs()->temp(0).reg() == EAX);
   ASSERT(locs()->temp(1).reg() == ECX);
   ASSERT(locs()->temp(2).reg() == EDX);
   Register result = locs()->out(0).reg();
+  const intptr_t argc_tag = NativeArguments::ComputeArgcTag(function());
+  const bool is_leaf_call =
+      (argc_tag & NativeArguments::AutoSetupScopeMask()) == 0;
 
   // Push the result place holder initialized to NULL.
   __ PushObject(Object::ZoneHandle());
   // Pass a pointer to the first argument in EAX.
   if (!function().HasOptionalParameters()) {
     __ leal(EAX, Address(EBP, (kParamEndSlotFromFp +
                                function().NumParameters()) * kWordSize));
   } else {
     __ leal(EAX, Address(EBP, kFirstLocalSlotFromFp * kWordSize));
   }
   __ movl(ECX, Immediate(reinterpret_cast<uword>(native_c_function())));
-  __ movl(EDX, Immediate(NativeArguments::ComputeArgcTag(function())));
-  const ExternalLabel* stub_entry =
-      (is_bootstrap_native()) ? &StubCode::CallBootstrapCFunctionLabel() :
-                                &StubCode::CallNativeCFunctionLabel();
+  __ movl(EDX, Immediate(argc_tag));
+  const ExternalLabel* stub_entry = (is_bootstrap_native() || is_leaf_call) ?
+      &StubCode::CallBootstrapCFunctionLabel() :
+      &StubCode::CallNativeCFunctionLabel();
   compiler->GenerateCall(token_pos(),
                          stub_entry,
                          PcDescriptors::kOther,
                          locs());
   __ popl(result);
 }
 
 
 static bool CanBeImmediateIndex(Value* value, intptr_t cid) {
   ConstantInstr* constant = value->definition()->AsConstant();
@@ skipping 2494 matching lines @@
 }
 
 
 LocationSummary* CheckEitherNonSmiInstr::MakeLocationSummary(Isolate* isolate,
                                                              bool opt) const {
   intptr_t left_cid = left()->Type()->ToCid();
   intptr_t right_cid = right()->Type()->ToCid();
   ASSERT((left_cid != kDoubleCid) && (right_cid != kDoubleCid));
   const intptr_t kNumInputs = 2;
   const bool need_temp = (left()->definition() != right()->definition())
-                      &&(left_cid != kSmiCid)
+                      && (left_cid != kSmiCid)
                       && (right_cid != kSmiCid);
   const intptr_t kNumTemps = need_temp ? 1 : 0;
   LocationSummary* summary = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
   summary->set_in(1, Location::RequiresRegister());
   if (need_temp) summary->set_temp(0, Location::RequiresRegister());
   return summary;
 }
 
@@ skipping 2949 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(ArgumentCount());  // Discard arguments.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_IA32