Port FastNewClosureStub introduced for ia32 in r3477 to x64 and arm.

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
===================================================================
--- src/x64/codegen-x64.cc	(revision 3577)
+++ src/x64/codegen-x64.cc	(working copy)
@@ -2196,19 +2196,28 @@
 
 
 void CodeGenerator::InstantiateBoilerplate(Handle<JSFunction> boilerplate) {
-  // Call the runtime to instantiate the function boilerplate object.
+  ASSERT(boilerplate->IsBoilerplate());
+
   // The inevitable call will sync frame elements to memory anyway, so
   // we do it eagerly to allow us to push the arguments directly into
   // place.
-  ASSERT(boilerplate->IsBoilerplate());
   frame_->SyncRange(0, frame_->element_count() - 1);
 
-  // Create a new closure.
-  frame_->EmitPush(rsi);
-  __ movq(kScratchRegister, boilerplate, RelocInfo::EMBEDDED_OBJECT);
-  frame_->EmitPush(kScratchRegister);
-  Result result = frame_->CallRuntime(Runtime::kNewClosure, 2);
-  frame_->Push(&result);
+  // Use the fast case closure allocation code that allocates in new
+  // space for nested functions that don't need literals cloning.
+  if (scope()->is_function_scope() && boilerplate->NumberOfLiterals() == 0) {
+    FastNewClosureStub stub;
+    frame_->Push(boilerplate);
+    Result answer = frame_->CallStub(&stub, 1);
+    frame_->Push(&answer);
+  } else {
+    // Call the runtime to instantiate the function boilerplate
+    // object.
+    frame_->EmitPush(rsi);
+    frame_->EmitPush(boilerplate);
+    Result result = frame_->CallRuntime(Runtime::kNewClosure, 2);
+    frame_->Push(&result);
+  }
 }
 
 
@@ -6066,6 +6075,49 @@
 }
 
 
+void FastNewClosureStub::Generate(MacroAssembler* masm) {
+  // Clone the boilerplate in new space. Set the context to the
+  // current context in rsi.
+  Label gc;
+  __ AllocateInNewSpace(JSFunction::kSize, rax, rbx, rcx, &gc, TAG_OBJECT);
+
+  // Get the boilerplate function from the stack.
+  __ movq(rdx, Operand(rsp, 1 * kPointerSize));
+
+  // Compute the function map in the current global context and set that
+  // as the map of the allocated object.
+  __ movq(rcx, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX)));
+  __ movq(rcx, FieldOperand(rcx, GlobalObject::kGlobalContextOffset));
+  __ movq(rcx, Operand(rcx, Context::SlotOffset(Context::FUNCTION_MAP_INDEX)));
+  __ movq(FieldOperand(rax, JSObject::kMapOffset), rcx);
+
+  // Clone the rest of the boilerplate fields. We don't have to update
+  // the write barrier because the allocated object is in new space.
+  for (int offset = kPointerSize;
+       offset < JSFunction::kSize;
+       offset += kPointerSize) {
+    if (offset == JSFunction::kContextOffset) {
+      __ movq(FieldOperand(rax, offset), rsi);
+    } else {
+      __ movq(rbx, FieldOperand(rdx, offset));
+      __ movq(FieldOperand(rax, offset), rbx);
+    }
+  }
+
+  // Return and remove the on-stack parameter.
+  __ ret(1 * kPointerSize);
+
+  // Create a new closure through the slower runtime call.
+  __ bind(&gc);
+  __ pop(rcx);  // Temporarily remove return address.
+  __ pop(rdx);
+  __ push(rsi);
+  __ push(rdx);
+  __ push(rcx);  // Restore return address.
+  __ TailCallRuntime(ExternalReference(Runtime::kNewClosure), 2, 1);
+}
+
+
 void ToBooleanStub::Generate(MacroAssembler* masm) {
   Label false_result, true_result, not_string;
   __ movq(rax, Operand(rsp, 1 * kPointerSize));