[turbofan] Avoid going through ArgumentsAdaptorTrampoline for CSA/C++ builtins

src/code-stub-assembler.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #include "src/code-stub-assembler.h"
 #include "src/code-factory.h"
 #include "src/frames-inl.h"
 #include "src/frames.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 8481 matching lines @@
   DCHECK_EQ(argc_mode_, mode);
   CSA_ASSERT(assembler_,
              assembler_->UintPtrOrSmiLessThan(index, GetLength(), mode));
   return assembler_->Load(MachineType::AnyTagged(), AtIndexPtr(index, mode));
 }
 
 Node* CodeStubArguments::AtIndex(int index) const {
   return AtIndex(assembler_->IntPtrConstant(index));
 }
 
+Node* CodeStubArguments::GetOptionalArgumentValue(int index,
+                                                  Node* default_value) {
+  typedef CodeStubAssembler::Variable Variable;
+  Variable result(assembler_, MachineRepresentation::kTagged);
+  CodeStubAssembler::Label argument_missing(assembler_),
+      argument_done(assembler_, &result);
+
+  assembler_->GotoIf(assembler_->IntPtrOrSmiGreaterThanOrEqual(

[Igor Sheludko, 2017/04/27 10:38:05]

s/IntPtr/UintPtr/ to be in sync with AtIndex.

[danno, 2017/04/28 06:58:10]

Done.

+                         assembler_->IntPtrOrSmiConstant(index, argc_mode_),
+                         argc_, argc_mode_),
+                     &argument_missing);
+  result.Bind(AtIndex(index));
+  assembler_->Goto(&argument_done);
+
+  assembler_->BIND(&argument_missing);
+  result.Bind(default_value);
+  assembler_->Goto(&argument_done);
+
+  assembler_->BIND(&argument_done);
+  return result.value();
+}
+
 void CodeStubArguments::ForEach(
     const CodeStubAssembler::VariableList& vars,
     const CodeStubArguments::ForEachBodyFunction& body, Node* first, Node* last,
     CodeStubAssembler::ParameterMode mode) {
   assembler_->Comment("CodeStubArguments::ForEach");
   if (first == nullptr) {
     first = assembler_->IntPtrOrSmiConstant(0, mode);
   }
   if (last == nullptr) {
     DCHECK_EQ(mode, argc_mode_);
@@ skipping 140 matching lines @@
         formatted.c_str(), TENURED);
     CallRuntime(Runtime::kGlobalPrint, NoContextConstant(),
                 HeapConstant(string));
   }
   CallRuntime(Runtime::kDebugPrint, NoContextConstant(), tagged_value);
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8